subject:(Electronic Data Processing Distributed Processing)

Nanyang Technological University

1. Wang, Yue. 2D object segmentation and matching using B-spline model .

Degree: 2005, Nanyang Technological University

► Including: 2 parts. This is part b. This thesis presents a research work on object segmentation and matching using a Bspline model. The B-spline is… (more)

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Electronic systems::Signal processing

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APA (6^th Edition):

Wang, Y. (2005). 2D object segmentation and matching using B-spline model . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/3708

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Yue. “2D object segmentation and matching using B-spline model .” 2005. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/3708.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Yue. “2D object segmentation and matching using B-spline model .” 2005. Web. 13 Dec 2019.

Vancouver:

Wang Y. 2D object segmentation and matching using B-spline model . [Internet] [Thesis]. Nanyang Technological University; 2005. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/3708.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang Y. 2D object segmentation and matching using B-spline model . [Thesis]. Nanyang Technological University; 2005. Available from: http://hdl.handle.net/10356/3708

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

2. Zhang, Xue. Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/68730

► Wave Energy Resource Assessment is essential to have a reliable prediction o f the power output and energy expected from various wave energy devices. The… (more)

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA (6^th Edition):

Zhang, X. (2016). Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/68730

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Xue. “Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/68730.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Xue. “Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) .” 2016. Web. 13 Dec 2019.

Vancouver:

Zhang X. Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/68730.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang X. Wave energy resource characterization and power prediction around Tanah Merah Ferry Terminal (TMFT) . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/68730

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Harikrishna Raj, Pinkymol. Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/68113

► Multilevel converters are very popular in medium/high power conversions due to their capability to generate high quality voltage magnitudes with low harmonics while employing devices… (more)

▼ Multilevel converters are very popular in medium/high power conversions due to their capability to generate high quality voltage magnitudes with low harmonics while employing devices of smaller voltage ratings. The output voltage waveform of multilevel inverter consists of multiple steppes of smaller magnitudes designed to reduce electromagnetic interference (EMI) commonly produced by rapid switching that generate lesser common mode currents at motor shaft and bearings due to reduced dv dt . The neutral point clamped (NPC), cascaded H-bridge (CHB) and flying capacitor (FC) converters are considered as the three classical multilevel converter topologies which have found their way to industrial applications almost two decades ago. To expand the application field of multilevel converters by overcoming the challenges associated with classical topologies, new multilevel topologies and modulation techniques are developed. In this thesis, various NPC multilevel inverter topologies and its modulation techniques are investigated. Diode-clamped multilevel inverter (DCMI) for more than three-level operation is less attractive due to dc-link capacitor voltage unbalancing issues and increased conduction loses caused by the commutation of (n-1) × (n-2) clamping diodes connected in series per-leg of an n-level diode clamped inverter. A converter topology with minimum number of series connected devices which balance the total voltage equally between the semiconductors and new multilevel modulation schemes, which on more number of levels, redundant voltage vectors and zero common mode voltage vectors available in higher level DCMI, can be used together to solve the above mentioned issues. In this thesis, the voltage unbalance issues and capacitor voltage balancing techniques in DCMI are studied in detail. An extensive analysis of two modulation techniques, level-shifted PWM (LS-PWM) and space vector modulation (SVM) are presented and a SVM based voltage balancing strategy for three-level and five-level diode clamped inverters are developed by utilizing redundant switching vectors without the need of any additional controls or auxiliary circuits. The proposed balancing strategy is tested on a five-level reduced device topology. Multiple-pole multilevel diode clamped inverter (M2DCI) which is derived from three-level DCMI topology and uses lesser number of clamping diodes compared to the classic five-level DCMI. The capacitor currents as well as dc-link intermediate branch currents are obtained from the switching function model of five-level M2DCI, which reduces the number of calculations at each sampling periods while implementing the voltage balancing strategy when compared to sector based methods. The stability limits of the proposed voltage balancing strategy for M2DCI based on load power factor angle and modulation indices have been obtained at various load conditions. The investigations shown here are modeled in Matlab/Simulink® and PSIM environment and verified using experimental results. It is found that to achieve capacitor…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

…ELECTRONICS · Micro Grid with PV, wind and Distributed Energy Storage. · Transmission System…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Harikrishna Raj, P. (2016). Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/68113

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Harikrishna Raj, Pinkymol. “Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/68113.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Harikrishna Raj, Pinkymol. “Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing .” 2016. Web. 13 Dec 2019.

Vancouver:

Harikrishna Raj P. Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/68113.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Harikrishna Raj P. Multilevel diode clamped converter with space vector modulation and DC-link capacitor voltage balancing . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/68113

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

4. Pan, Zihan. MIMO coding and linear equalization schemes for asynchronous visible light communication system .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/65943

► In this thesis, we introduce a new form of indoor wireless communication: visible light communication (VLC). Both the traditional RF communication and visible light communication… (more)

▼ In this thesis, we introduce a new form of indoor wireless communication: visible light communication (VLC). Both the traditional RF communication and visible light communication are propagated through free space, hence many coding schemes for RF communication could also be applied to VLC. MIMO coding is suitable for VLC for two reasons: first, there are always multiple illumination sources in a room in practice, these light sources could work as multiple transmitters for MIMO VLC; secondly, the shadowing effect is very common in a VLC system, and MIMO coding could address this problem very effectively. Many MIMO coding schemes such as Orthogonal Space-Time Block Code (OSTBC) and Shift-Orthogonal Space-Time Block Code (SOSTBC) have been reported. These coding strategies are suitable under different conditions. In order to apply these orthogonal MIMO schemes, negative-value symbols need to be transmitted, but the light signal in low-cost VLC system is mostly intensity modulated with energy detection (particularly when the LED is not in the illumination mode but is still desired to be in the communication mode), so we cannot transmit negative symbols in the transmitters directly. To address this problem, we investigate special modulation schemes for intensity modulation to represent the negative symbols, and compare their performances with other transmission schemes under different channels. Furthermore, there are some practical system problems such as timing misalignment and multipath effect caused by un-synchronized transmitters and reflections. So the MIMO coding schemes should be adapted with equalization for these channels. Besides the SOSTBC mentioned above, for intensity modulated VLC systems we could also use Repetition Coding with Single-Carrier Frequency Domain Equalization (RC with SC-FDE) and Repetition Coding with Single-Carrier Over-Sampling Frequency Domain Equalization (RC with SC OS-FDE) to deal with these problems. In this thesis, these schemes are further extended for asynchronous channel with fractional delays. Finally we realize the VLC system on a hardware test bed. To build the MIMO VLC experimental test bed, we use an arbitrary waveform generator as a signal generator, and a digital oscilloscope as a signal receiver. The optical transmitter is a cool white LED, and the optical receiver is a wide bandwidth photodetector. Other necessary accessories include bias tees and constant voltage source, both of which are used to provide a DC bias voltage for the LED. The three MIMO schemes mentioned above are all realized in the experiment. Experimental BER results are collected, with low transmission rate (1Mb/s) and high transmission rate (10Mb/s), and with different asynchronous channel environment (integer delays and fractional delays). The experimental results largely verify the theories.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pan, Z. (2016). MIMO coding and linear equalization schemes for asynchronous visible light communication system . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/65943

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pan, Zihan. “MIMO coding and linear equalization schemes for asynchronous visible light communication system .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/65943.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pan, Zihan. “MIMO coding and linear equalization schemes for asynchronous visible light communication system .” 2016. Web. 13 Dec 2019.

Vancouver:

Pan Z. MIMO coding and linear equalization schemes for asynchronous visible light communication system . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/65943.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pan Z. MIMO coding and linear equalization schemes for asynchronous visible light communication system . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/65943

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

5. Yao, Enyi. Low power smart sensor circuits for biomedical applications : applications to neural interfaces .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/67221

► In this thesis, we proposed a novel low power, compact, current-mode spike detector with feature extractor for real-time neural recording systems where neural spikes or… (more)

▼ In this thesis, we proposed a novel low power, compact, current-mode spike detector with feature extractor for real-time neural recording systems where neural spikes or action potentials (AP) are of interest. Such a circuit can enable massive compression of data facilitating wireless transmission. This design can generate a high signal-to-noise ratio (SNR) output by approximating the popularly used nonlinear energy operator (NEO) through standard analog blocks. We show that a low pass filter after the NEO can be used for two functions – (i) estimate and cancel low frequency interference and (ii) estimate threshold for spike detection. The circuit is implemented in a 65 nm CMOS process and occupies 200 μm x 150 μm of chip area. Operating from a 0.7 V power supply, it consumes about 30 nW of static power and 7 nW of dynamic power for 100 Hz input spike rate making it the lowest power consuming spike detector reported so far. The feature extractor could be utilized to extract some features from the raw waveform that have enough information to discriminate between different shapes of recorded spike waveforms. The spike sorting was performed by our proposed hardware extreme learning machine system (ELM) which is a low power neuromorphic machine learner that can perform the local processing in smart sensors while dissipating very low power. The proposed circuit utilizes device mismatch prevalent in today's VLSI process to perform a significant part of the computation while a digital back end enables precision in the final output. The particular machine learning algorithm we use is extreme learning machine (ELM). Mismatch in silicon spiking neurons and synapses are used to perform the vector-matrix multiplication that forms the first stage of this classifier and is the most computationally intensive. System simulations and measurement have been conducted to evaluate the dependence of performance (in a classification and a regression task) on analog and digital parameters like weight resolution, maximum spike frequency etc. It is shown that the proposed implementation is more energy efficient as opposed to custom digital implementations for a classification task. In order to verify its function, some real-world bench mark binary classification datesets have been employed in the measurement showing that the performance of our design is comparable with recent publications and software simulations of other machine learning system. This system was implemented in a 0.35 μm CMOS process which can operate from 0.8 V to 3.3 V power supply with a lowest classification energy 0.2 nJ/op, maximum classification speed 564 MMAC/s.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yao, E. (2016). Low power smart sensor circuits for biomedical applications : applications to neural interfaces . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/67221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yao, Enyi. “Low power smart sensor circuits for biomedical applications : applications to neural interfaces .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/67221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yao, Enyi. “Low power smart sensor circuits for biomedical applications : applications to neural interfaces .” 2016. Web. 13 Dec 2019.

Vancouver:

Yao E. Low power smart sensor circuits for biomedical applications : applications to neural interfaces . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/67221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yao E. Low power smart sensor circuits for biomedical applications : applications to neural interfaces . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/67221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

6. Zhang, Wen. Feature weighting with augmented visual phrase in visual product recognition .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/68832

► Significant progress towards image search has been made in the past decade through the development of local invariant features. Among existing local feature detectors, the… (more)

▼ Significant progress towards image search has been made in the past decade through the development of local invariant features. Among existing local feature detectors, the Scale Invariant Feature Transform (SIFT) [1] is widely used since it is designed to be invariant to minimal illumination changes and certain geometric transformations. However, in practice, the recognition performance is still subject to actual condition and there still exist various cases that SIFT can't handle, such as non-linear illumination changes [2][3] and certain a ne transformation [4]. It is noted that images taken by mobile phones often su er from such variations. In order to address this issue, we propose a feature weighting algorithm to determine the stability of interest points under various photometric and geometric transformations. By assigning di fferent scores to these interest points according to the repeatibility they are in the augmented samples of diff erent illumination or geometric transformations, the stable interest points can be obtained. The Bag of Word (BoW) based representation is widely used in image visual search due to its good performance and high computational e fficiency. In traditional BoW representation, the local descriptors in the whole image are treated with equal importance. This restricts its performance as in most scenarios the local descriptors on foreground objects should be assigned more weight than the descriptors on the background. In view of this, we incorporate saliency information with the proposed feature weighting algorithm to further improve the performance. The weighted interest points are then used in the weighted scalable vocabulary tree (WSVT) framework for the image recognition task. Geometric veri fication (GV) is used to re-rank the images. Experimental results on a commercial product database show the proposed feature weighting algorithm outperforms the current SVT recognition without feature weighting by 5%. Moreover, with the popularity of image editing softwares and social media networking services such as Instagram and Facebook, a growing number of users tend to process digital images using various post-processing filters before uploading. Some SIFT features are not stable given the nonlinearity of these fi lters, which may degrade recognition performance. Therefore we further proposed a feature weighting method based on post-processing filters and incorporate it into the previous recognition framework. Experimental results on a commercial product database show the proposed algorithm outperforms the current SVT recognition without feature weighting by more than 10% in average recognition performance for various post-processing e ffects. Query images captured by mobile phones often suffer from illumination, scale, and viewpoint changes. This poses a great challenge in visual recognition. In view of this, we propose a framework that uses Augmented Visual Phrases (AVP) in the Bag-of-Phrase model. By checking the consistency between keypoints in the original image and augmented…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, W. (2016). Feature weighting with augmented visual phrase in visual product recognition . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/68832

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Wen. “Feature weighting with augmented visual phrase in visual product recognition .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/68832.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Wen. “Feature weighting with augmented visual phrase in visual product recognition .” 2016. Web. 13 Dec 2019.

Vancouver:

Zhang W. Feature weighting with augmented visual phrase in visual product recognition . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/68832.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang W. Feature weighting with augmented visual phrase in visual product recognition . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/68832

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

7. Song, Xiaochao. Effect of additives on sintering and conductivity of yttria-stabilized zirconia .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/68999

► The effect of additives on sintering and functional properties of ceramics is one of the on-going interests in the fabrication of high performance advanced components… (more)

▼ The effect of additives on sintering and functional properties of ceramics is one of the on-going interests in the fabrication of high performance advanced components for novel applications. In the present work, the effect of additives on yttria-stabilized zirconia (YSZ) was studied. YSZ is a well accepted electrolyte material used in solid oxide fuel cell (SOFC) system. In the multi-layer SOFC system, YSZ is sandwiched between the anode (Ni/YSZ cermet) and cathode (Sr-doped LaMn03)' There are several practical concerns in the co-sintering of this system, such as the higher sintering temperature of YSZ than that of the electrodes, unavoidable interdiffusion of NiO from anode, and ubiquitous presence of Si02 impurity. The present work focuses on the understanding of the influence of the additives, either in the form of purposely added Ah03 or inevitably existed NiO, Si02 , on sintering and conductivity of YSZ. The study aims to clarify the sintering mechanisms, hence shed light to the lowering of the sintering temperature, and to improve the conductivity of YSZ. Through the study, we also established models that provide prediction on the microstructural evolution during sintering, which could support the design of new material system in co-sintering and other application. It has been reported that a small amount of Ah03 or NiO could enhance the densification of YSZ, however, it was found in the present work that in the heavily doped YSZ samples, there exists an optimal additive amount for the densification. Grain growth of YSZ was also found to be initially advantageous by Al203 or NiO addition, but showed deteriorating effect upon further addition. In the present work, densification and grain growth kinetics of YSZ with/without additives were studied via the proposed master curve approach, which consists of Master Densification Curve (MDC) and Master Grain Growth Curve (MGGC) approach. During the firststage sintering (p = 60%), the abnormally higher activation energy (620730 kJImol) was observed, which was attributed to the contribution from interface reaction and surface diffusion. For the second stage of sintering (60% ~ p ~ 95%), lattice diffusion was proposed as the dorninant rnechanism for undoped 8YSZ. However, upon 1.0 wt.% A1203, or 0.28 wt.% NiO addition, grain boundary diffusion was found to significantly contribute to the densification, where the activation energy was noted to decrease about 250 k.l /rnol. The proposed MDC as well as MGGC were found to be able to facilitate prediction of microstructural evolution with good accuracy for a wide range of sintering profiles. In order to further reduce the sintering temperature of YSZ, the approach of co-addition of Ab03 and Si02 was evaluated. The lowest temperature for maximum densification rate (Tm ax ) has been achieved at 1210°C in YSZ with 0.5 wt.% Ab03 and 0.05 wt.% Si02 co-additives. The improved densification behavior is ascribed to the enhanced grain boundary diffusivity and liquid phase sintering. Finally,…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Song, X. (2016). Effect of additives on sintering and conductivity of yttria-stabilized zirconia . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/68999

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Song, Xiaochao. “Effect of additives on sintering and conductivity of yttria-stabilized zirconia .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/68999.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Song, Xiaochao. “Effect of additives on sintering and conductivity of yttria-stabilized zirconia .” 2016. Web. 13 Dec 2019.

Vancouver:

Song X. Effect of additives on sintering and conductivity of yttria-stabilized zirconia . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/68999.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Song X. Effect of additives on sintering and conductivity of yttria-stabilized zirconia . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/68999

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

8. De, Jaydeep. Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/65993

► Filamentary structured objects are everywhere in nature and man-made architectures. These are found in the network of neurons, blood vessels, roads and others, which can… (more)

▼ Filamentary structured objects are everywhere in nature and man-made architectures. These are found in the network of neurons, blood vessels, roads and others, which can scale from a range of few microns (in case of neurons) to thousands of kilometers (in case of roads). Image-based analysis of these filamentary structured objects are of great interest as they offer important information about the structure and connectivity of such networks which can help us in applications such as drug screening for neurological disorders or computer-aided diagnosis of diabetic retinopathy. However, the task is challenging due to the bottleneck of filament crossover issue, which essentially hinders the use of existing systems in large-scale applications. The aim of the thesis is to build a generic graph-based framework for tracing the images of filamentary structured objects. The framework consists of two steps: preprocessing step consisting of segmentation, skeleton extraction, digraph representation and tracing step using graph-based methods. The main focus of this thesis is the second step. After the preprocessing step, the skeleton is represented as a directed graph structure where skeleton segments are represented as nodes in the graph and there is an edge between two nodes if the corresponding skeletons are touching each other. Now, the goal is to cluster the graph into disjoint trees where the number of clusters depends on the number of tree structures in the filament. This is achieved by assuming that at least one node is labeled in each cluster of the graph. Given the structure of the graph and one labeled node per cluster, the problem becomes that of assigning class labels to the rest of the unlabeled nodes. The problem is formulated as a label propagation problem on a weighted digraph using the Matrix Forest Theorem. The normalized conductance of a rooted spanning converging forest of a digraph is used as a similarity score between the labeled and unlabeled nodes. The label propagation problem can also be formulated as a random walk on an Absorbing Markov Chain (AMC). After converting the original graph into an AMC, the Fundamental Matrix is computed, which is the expected number of visits from one node to another before absorption. For tracing problem, this is another kind of similarity score between the labeled and unlabeled nodes. For both approaches, the class label for an unlabeled node is the same as that of a labeled node with largest similarity. If the weight matrix is formulated as parametric functions then the parameters can be determined by maximizing the sum of the logarithm of expected number of visits from unlabeled nodes to the labeled nodes. For the scenario where the class labels for only very few nodes are known, the parameter estimation problem is solved by Expectation Maximization (EM) algorithm. For comparison purpose, the tracing problem is also formulated as a Maximum A Posteriori (MAP) inference problem in Undirected Graphical Models. Empirical analysis is…

Subjects/Keywords: DRNTU::Engineering::Computer science and engineering::Computing methodologies::Pattern recognition; DRNTU::Engineering::Computer science and engineering::Computing methodologies::Image processing and computer vision; DRNTU::Engineering::Computer science and engineering::Computing methodologies::Artificial intelligence

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

De, J. (2016). Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/65993

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

De, Jaydeep. “Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/65993.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

De, Jaydeep. “Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images .” 2016. Web. 13 Dec 2019.

Vancouver:

De J. Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/65993.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

De J. Graph-based tracing of filamentary structured objects with applications in neuronal and retinal images . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/65993

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

9. Luo, Kaiming. Investigation of nano-copper for electronic packaging application : solder metallization and die attach .

Degree: 2016, Nanyang Technological University

URL: http://hdl.handle.net/10356/66939

► Nano-copper (NC) has been developed recently with good potential for electronic packaging applications. In this work, the interfacial reaction between NC and Sn-3.5Ag and the… (more)

▼ Nano-copper (NC) has been developed recently with good potential for electronic packaging applications. In this work, the interfacial reaction between NC and Sn-3.5Ag and the adhesion between NC and different metallizations were investigated. Thermal Gravimetric Analysis (TGA) results of NC paste were used to help determine the best sintering condition of NC paste. Heating NC paste at 230 ºC for 10 min at N2 atmosphere is the optimal sintering condition. The sintered NC paste shows a porous nanocrystal structure. In the solder interfacial reaction study with Sn-3.5Ag, plated Cu was used as a reference. Both sintered NC/Sn-3.5Ag and plated Cu/Sn-3.5Ag samples were reflowed for different time spans to obtain their morphology and kinetic information. The morphology changes from 10s to 5 hours reflow showed that the interfacial reaction of NC/Sn-3.5Ag is quite different from Cu/Sn-3.5Ag. NC/Sn-3.5Ag produces porous and elongated scallop-type Intermetallic Compounds (IMCs) while Cu/Sn-3.5Ag only forms scallop-type IMCs. The cause of this morphology difference is due to nano-copper’s unique porous structure. Based on the Scanning Electron Microscope (SEM) and (Energy Dispersive X-ray Spectroscopy) EDS analysis of samples of different reflow times, an IMC growth mechanism in NC/Sn-3.5Ag has been proposed. To quantify NC/Sn-3.5Ag and Cu/Sn-3.5Ag interfacial reaction, a kinetics analysis of the interfacial IMC growth was carried out. Results show that NC/Sn-3.5Ag reaction is faster than Cu/Sn-3.5Ag reaction. The growth of Cu6Sn5 in Cu/Sn-3.5Ag follows t1/3 growth kinetics while the growth of Cu6Sn5 in NC/Sn-3.5Ag follows t1/2 growth kinetics. By comparing experiment result with kinetics model, we conclude that the IMC growth in Cu/Sn-3.5Ag is controlled by diffusion through fast diffusion channel such as the IMC grooves while NC/Sn-3.5Ag reaction is mainly controlled by diffusion through the existing IMC layers. In the adhesion study between NC and different metallzations, NC as a potential joining material was evaluated by cross-cut test and die-shear test. Different metallizations were prepared by either sputtering or electrochemical method. These metallizations are chosen because they are either commercialized in the industry or have shown very good performance in lead-free solder applications. Even though NC can directly bond with Cu surface without forming IMCs, for the purpose of its potential as a joining material used in the future, it is essential to understand its adhesion conditions with different metallizations. Different metallizations were prepared and analyzed by SEM, EDS and Atomic Force Microscope (AFM). The surface roughness, element concentration and metallization layer thickness were obtained and analyzed. Cross-cut adhesion test shows that Cu, ENIG, Cr/Ni/Au and Ni-Sn-P have relatively better adhesion with NC than Ni-P, Ni-W-P, Ni-Co-P. Shear test result reveals that Cu has the best adhesion with NC. By fractographic analysis of the shear test result, NC/Cu failure mode is verified as bulk…

Subjects/Keywords: DRNTU::Engineering::Materials::Electronic packaging materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Luo, K. (2016). Investigation of nano-copper for electronic packaging application : solder metallization and die attach . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/66939

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Luo, Kaiming. “Investigation of nano-copper for electronic packaging application : solder metallization and die attach .” 2016. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10356/66939.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Luo, Kaiming. “Investigation of nano-copper for electronic packaging application : solder metallization and die attach .” 2016. Web. 13 Dec 2019.

Vancouver:

Luo K. Investigation of nano-copper for electronic packaging application : solder metallization and die attach . [Internet] [Thesis]. Nanyang Technological University; 2016. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10356/66939.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Luo K. Investigation of nano-copper for electronic packaging application : solder metallization and die attach . [Thesis]. Nanyang Technological University; 2016. Available from: http://hdl.handle.net/10356/66939

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

10. Trippe, Annette Erika. Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/45666

► The emergence and upswing of battery electric vehicles fuels discussion and research on the impact of those on the power system and how they can… (more)

▼ The emergence and upswing of battery electric vehicles fuels discussion and research on the impact of those on the power system and how they can be used beneficially. On the other hand, the battery is very sensitive to different modes of operation and can age rapidly. This can lead to high losses in value of the electric vehicle because the battery accounts for a substantial share in the cost. In this work, an optimisation model is developed in order to generate intelligent charging strategies for battery electric vehicles. The model considers both electricity price and battery ageing and thereby allocates charging strategies representing the optimal trade-off between electricity price controlled charging and battery lifetime. A mobility model is elaborated to simulate the energy consumption of the respective vehicles as well as the driving and parking schedules of the users. The simulated travel schedules and energy consumption serve as input for the optimisation model of intelligent charging strategies. Experimental data of battery ageing tests, designed to mirror the operation of lithium-ion batteries in electric vehicles, are the basis for a comprehensive battery ageing model. Both cycle and calendar ageing are examined and the influence of the state of charge, charge rate, as well as range of operation on battery ageing is investigated. A calendar ageing function as well as a three-dimensional cycle ageing function are derived, modelling the battery ageing within the optimisation. The charging optimisation model minimises the total charging costs, consisting of charging electricity cost and battery ageing cost. The mathematical optimisation problem is initially formulated as a mixed-integer non-linear programme and transformed into a mixed-integer linear programme by means of piecewise linear approximation and other linearisation techniques. The charging optimisation model is applied to a sample of 300 battery electric vehicles and different scenarios are computed and analysed. The battery ageing cost accounts for 13% to 45% of the total charging costs for the different scenarios, underlining the importance of the inclusion of battery ageing into the optimisation of charging strategies. The optimal operating range lies between a battery state of charge of 10% to 50% in most cases. Charging times coincide with times of low electricity prices, usually correlated to valleys in the electricity demand. Almost no fast charging is applied, indicating that the higher battery ageing cost due to fast charging cannot be outweighed by a reduction in electricity cost when charging more energy during low-priced periods.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Electric power

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Trippe, A. E. (2018). Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/45666

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Trippe, Annette Erika. “Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/45666.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Trippe, Annette Erika. “Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing .” 2018. Web. 13 Dec 2019.

Vancouver:

Trippe AE. Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/45666.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Trippe AE. Optimisation model of intelligent charging strategies for battery electric vehicles considering the power system and battery ageing . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/45666

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

11. Wang, Dong. Design of low-power PVT-aware circuits for power management applications .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/45692

► In recent electronics industry, power management plays a significant role to extend the battery life of battery-powered portable electronic devices. Due to the push for… (more)

▼ In recent electronics industry, power management plays a significant role to extend the battery life of battery-powered portable electronic devices. Due to the push for low-power CMOS circuits, the power-aware design agenda will be addressed in the power management circuits. Besides, turning to sub-90nm CMOS technologies in System-on-Chip (SoC) environment, the performances are often significantly influenced by process, supply voltage and temperature (PVT) variations. These two key issues impose design challenges to circuits that are able to sustain the targeted specifications and to provide good fabrication yield. To tackle the stated problems, this work aims to explore the research, design, analysis and implementation of low-power PVT-aware circuits for power management applications in advanced nanometer CMOS technologies. In an exemplary application of a smart power system that the supply voltage can be a function of device’s threshold voltage (VTH) to counteract the process variation, a threshold voltage reference circuit is often needed in the design. This thesis will present the MOSFET VTH reference circuit that employs a dual-segment nonlinear temperature compensation method to provide thermal stability. Besides, the supply insensitivity is another key design parameter to be addressed in this work. The measured results have indicated that the VTH reference circuit yields a T.C. of 28.7 ppm/oC, power supply rejection (PSR) of -43.5 dB at 10 MHz and line sensitivity of 70.8 ppm/V. The performance metrics are better than those of reported works. In another circuit of the above power system, it requires a stable current source. This work presents a new current source architecture which is the embodiment of a process-tolerant bias current circuit and a scaled process-tracking bias voltage source for the dedicated temperature-compensated voltage-to-current (VI) conversion. The measurement results have shown that the current source consumes a quiescent power of 7.18 μW whilst achieving a sensitivity figure-of-merit (FOM) of 2.34% in terms of total PVT variation. Such the low-power low-sensitive features are better than most of the reported works and comparable with the state of art. On top of that, there exists another challenge from the non-ideal CMOS stress effect that causes the performance degradation in the PVT-aware circuits. In this work, a new electrical model is proposed to predict the stress effect that impacts on the electrical performance of reference circuits. It has validated that there is a reasonable correlation between the model prediction results and the measurement results of the above stated voltage and current reference circuits. Of particular noted, this is the first electrical model that addresses the impact of stress effect on the reference circuit designs in the field. In the low-dropout (LDO) regulator dedicated to power management applications where low power, low voltage, low transient spike and sustainability of transient metrics are concerned, the circuit techniques are the…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, D. (2018). Design of low-power PVT-aware circuits for power management applications . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/45692

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Dong. “Design of low-power PVT-aware circuits for power management applications .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/45692.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Dong. “Design of low-power PVT-aware circuits for power management applications .” 2018. Web. 13 Dec 2019.

Vancouver:

Wang D. Design of low-power PVT-aware circuits for power management applications . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/45692.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang D. Design of low-power PVT-aware circuits for power management applications . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/45692

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

12. Zhu, Qingchang. Building occupant sensing : occupancy prediction and behavior recognition .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/45814

► Minimizing energy consumption and maintaining occupants’ comfort levels are of topical and growing interest as people spend much time inside buildings. To achieve these goals… (more)

▼ Minimizing energy consumption and maintaining occupants’ comfort levels are of topical and growing interest as people spend much time inside buildings. To achieve these goals in smart buildings, it is necessary to study the problem of occupant sensing by leveraging machine learning methods to understand occupants based on sensor signals. In this dissertation, we study occupant sensing by answering this question in two aspects: what are the occupants’ levels and behaviors? Existing methods based on feature engineering for occupant sensing are still un- satisfactory. In this thesis, we propose four frameworks based on feature learning to perform occupancy level prediction and occupant behavior recognition. For occupancy level prediction, we propose a framework of neural networks with local receptive fields to process the environmental data, especially those of CO2. Real experiments are conducted in a laboratory to evaluate the effectiveness of the proposed framework. Besides, we demonstrate that when the time-domain data is combined with frequency-domain ones, it could provide much valuable information during the feature extraction process to improve the performance of the classification of occupancy levels. Occupancy levels are the coarse information, but occupants’ behaviors are the fine- grained ones. The occupant behavior recognition problem is further divided into simple motion-related activity recognition with inertial measurements and energy- related sound event recognition. For simple motion-related activity recognition based on Inertial Measurement Unit, i.e. accelerometer, gyroscope and magnetometer, we propose a semi-supervised learning framework using Deep Long Short- Term Memory method. As the unlabeled data is pervasively available, the pro- posed method could enhance performance of the classification of simple motions. Moreover, for lightweight computing purpose, a feature learning framework based on dictionary learning is also proposed to recognize simple motion-related activities based on built-in inertial sensors of smartphones. Real experiments based on our collected inertial sensing data and some public data demonstrate that the performance of the proposed simple occupant behavior recognition is significantly improved. As simple behavior alone is not enough to enrich the understanding of occupants and indoor environments, energy-related sound event recognition is also studied for the interactive activities between occupants and appliances based on built-in microphones of smartphones. We propose a dictionary learning framework for the computationally lightweight sound event recognition application on smartphones. Furthermore, to improve the performance based on distinctive representations of recorded sound signals, the feature learning framework based on neural networks with local receptive fields is also proposed to recognize energy-related sound events. Experimental results based on our collected audio dataset and some public dataset demonstrate the effectiveness of the proposed frameworks.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhu, Q. (2018). Building occupant sensing : occupancy prediction and behavior recognition . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/45814

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhu, Qingchang. “Building occupant sensing : occupancy prediction and behavior recognition .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/45814.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhu, Qingchang. “Building occupant sensing : occupancy prediction and behavior recognition .” 2018. Web. 13 Dec 2019.

Vancouver:

Zhu Q. Building occupant sensing : occupancy prediction and behavior recognition . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/45814.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhu Q. Building occupant sensing : occupancy prediction and behavior recognition . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/45814

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

13. Xing, Weichuan. InAlN/GaN high electron mobility transistors on Si for RF applications .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/45971

► Conventional AlGaN/GaN High Electron Mobility Transistors (HEMTs) have been proven to be a strong competitor in both high voltage and high frequency applications resulting from… (more)

▼ Conventional AlGaN/GaN High Electron Mobility Transistors (HEMTs) have been proven to be a strong competitor in both high voltage and high frequency applications resulting from the intrinsic material properties of GaN such as large bandgap, high electron mobility, high electron saturation velocity and high thermal conductivity. In the past decades, GaN HEMTs have emerged as one of the hottest research topics and intensively studied. The performance of conventional AlGaN/GaN HEMTs have been improved significantly and continuously in the past decades, such as high output power, high operation frequency and low noise figure. Recently, a novel heterostructure with a thin layer of InAlN on top of GaN have been demonstrated to further improve the high frequency performance of GaN HEMTs. Benefiting from the unique properties of InAlN/GaN hetrostructure such as very thin top barrier thickness, high electron density and lattice match, the high frequency performance of GaN HEMTs have been pushed to the next level. On the other hand, there are still some critical challenges limiting the applications of GaN HEMTs. On key issue is that most of the high frequency results, especially those above 200 GHz, were reported from devices grown on SiC substrates. SiC has the advantages of small lattice mismatch to GaN eplilayers, very high resistivity and thermal conductivity. Thus, GaN HEMTs grown on SiC can achieve higher RF performance than those grown on Si. However, GaN HEMT on SiC is not cost-effective and is only available in smaller sizes (≥ 6 inch) which make it less attractive to be adopted commercially. To reduce the cost of GaN HEMTs, Si substrates have attracted increasing interest in recent years, not only in power electronics applications but also in RF applications. Significant efforts have been made on improving the epitaxial quality of GaN on Si substrates as well as the device fabrication technology. As a result, the performance of RF GaN HEMTs on Si has improved significantly. However, the high frequency performance of GaN HEMTs on Si still lags behind their counterparts on SiC. The best reported AlGaN/GaN HEMT on Si only exhibited a fT of 176 GHz with for a gate length of 80 nm. Another drawback is the poor linearity performance of deeply scaled GaN HEMTs. Linearity is an important parameter for GaN HEMTs to be applied as amplifiers in modern communication system. GaN HEMT is expected to maintain high operation frequency at high gate bias to support its application for large signal RF operation. However, poor linearity characteristics have been observed in the conventional GaN HEMTs. It is manifested by a non-flat transconductance (gm) and fT, fmax versus gate bias (or drain current). After reaching its maximum point, gm or fT, fmax decrease drastically with the increasing gate bias. Linearity of GaN transistors ultimately limits the power density and efficiency of these devices in many applications, as the operating point of the device typically needs to be backed-off to meet the linearity…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Xing, W. (2018). InAlN/GaN high electron mobility transistors on Si for RF applications . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/45971

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xing, Weichuan. “InAlN/GaN high electron mobility transistors on Si for RF applications .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/45971.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xing, Weichuan. “InAlN/GaN high electron mobility transistors on Si for RF applications .” 2018. Web. 13 Dec 2019.

Vancouver:

Xing W. InAlN/GaN high electron mobility transistors on Si for RF applications . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/45971.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xing W. InAlN/GaN high electron mobility transistors on Si for RF applications . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/45971

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

14. Gusakova, Julia. Structure and electronic properties of 2D transition metal dichalcogenides : first principles study .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46006

► Semiconducting transition metal dichalcogenides (TMDs) represent a class of layered materials with nonzero band gap, and as a result attract great attention. Density functional theory… (more)

▼ Semiconducting transition metal dichalcogenides (TMDs) represent a class of layered materials with nonzero band gap, and as a result attract great attention. Density functional theory (DFT) is a method of choice for theoretical exploration of condensed matter. However, there exists well-known problem with band gap evaluation within DFT framework. Thus, general theoretical approach for an accurate band gap computation within DFT is in big demand, which can be used for exploration of new materials with the required properties. The thesis introduces recently proposed the general method for the band gap calculation (GVJ-2e). GVJ-2e method is implemented within DFT framework, is based solely on the total energy calculations and is adjustable parameter free. The GVJ-2e method was verified on wide range of materials from bulk semiconductors (ex. Si, C, Ge) to wide gap insulators (ex. Xe, Kr) and yielded the band gaps which correlate well with experimental ones. The errors of proposed method are smaller than errors of other widely used methods (GW, hybrid functional HSE, TB-mBJ functional). In the thesis the structural and electronic properties of bulk and monolayer TMDs (MoS2, MoSe2, WS2, WSe2) are studied. The calculated relaxed lattice parameters of bulk TMDs deviated from experimental values for less than 2%. The fundamental and optical band gaps are obtained with proposed GVJ-2e method and agree well with experimental results. From the analysis of Kohn-Sham band structures is shown that considered monolayer TMDs are direct gap semiconductors, while their bulk forms are indirect semiconductors. The structure, formation and electronic properties of monolayer MoS2(1-x)Se2x alloy are studied for entire range of substitution rates x from 0 to 1. The analysis of various structures of alloy demonstrated that the structures with almost symmetric occupation of top and bottom chalcogen planes by Se (S) atoms are most likely to occur during synthesis. The fundamental and optical band gaps are calculated with proposed GVJ-2e method and are found to be in range of corresponding band gaps of MoS2 and MoSe2 monolayers. It is shown that the dependency of the lattice parameter, fundamental and optical band gap on substitution rate (x) is nonlinear. The study of the electron and hole effective masses showed that both are smaller than a free electron mass and that in the alloy electrons are lighter than holes (similarly to MoS2 and MoSe2 monolayers) almost for all substitution rates. It was shown that the physics of the formation and properties of the MoS2(1-x)Se2x can be described in terms of percolation theory.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gusakova, J. (2018). Structure and electronic properties of 2D transition metal dichalcogenides : first principles study . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46006

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gusakova, Julia. “Structure and electronic properties of 2D transition metal dichalcogenides : first principles study .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46006.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gusakova, Julia. “Structure and electronic properties of 2D transition metal dichalcogenides : first principles study .” 2018. Web. 13 Dec 2019.

Vancouver:

Gusakova J. Structure and electronic properties of 2D transition metal dichalcogenides : first principles study . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46006.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gusakova J. Structure and electronic properties of 2D transition metal dichalcogenides : first principles study . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46006

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

15. Zhou, Chunluan. Learning detector ensembles for object detection .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46010

► Telling "what is where", object detection is a fundamental problem in computer vision and has a broad range of applications such as video surveillance and… (more)

▼ Telling "what is where", object detection is a fundamental problem in computer vision and has a broad range of applications such as video surveillance and autonomous driving. One major challenge of object detection comes from large intra-category appearance variations which are caused by factors including subcategory, viewpoint, deformation and occlusion. Large appearance variations make it difficult to model an object category properly such that the object category is well distinguished from other object categories as well as backgrounds. Learning a detector ensemble is a widely adopted solution to appearance variation handling. Appearance variations resulting from subcategories and viewpoints are usually handled by clustering object examples of a category into groups each of which represents one subcategory or viewpoint and then learning a detector for each group. For dealing with appearance variations due to deformations and occlusions, part-based detection methods have demonstrated their promise by integrating a set of part detectors to form a part detector ensemble. This thesis studies how to learn detector ensembles to better address deformations and occlusions, particularly the latter situation, for generic object detection as well as pedestrian detection. For generic object detection, two approaches are proposed to handle deformations and occlusions respectively based on a classic part detector ensemble, deformable part model (DPM). The former discovers a set of non-rectangular parts which can well fit object structures to replace the original rectangular parts in the DPM. The discovered non-rectangular parts can better capture the appearance of local regions and structural deformations of objects. The latter discovers a set of representative and discriminative occlusion patterns which share the same set of parts from a DPM trained on fully visible object examples. The discovered occlusion patterns are themselves DPMs, and when properly tuned, can be applied directly or combined with state-of-the-art detectors, e.g. Faster R-CNN for improving detection performance and achieving part-level occlusion reasoning. For pedestrian detection, two approaches are developed to improve two modules of a commonly used framework of learning a part detector ensemble respectively for handling occlusions. The first approach focuses on how to integrate part detectors properly to reduce negative effects from unreliable and irrelevant part detectors on heavily occluded pedestrian detection. The second approach aims to learn reliable part detectors jointly by sharing a set of decision trees among the part detectors to exploit part correlations and also reduce the computational cost of applying these part detectors. Experimental results on pedestrian detection benchmark datasets show promising performance of the two approaches for detecting partially occluded pedestrians, especially heavily occluded ones.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhou, C. (2018). Learning detector ensembles for object detection . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46010

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhou, Chunluan. “Learning detector ensembles for object detection .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46010.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhou, Chunluan. “Learning detector ensembles for object detection .” 2018. Web. 13 Dec 2019.

Vancouver:

Zhou C. Learning detector ensembles for object detection . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46010.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhou C. Learning detector ensembles for object detection . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46010

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

16. Nguyen, Viet Hung. Model-based diagnosis and prognosis of induction motors under stator winding fault .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46022

► Induction machines are widely used in industries and essential parts of industrial systems. Despite their rugged construction, they are subject to fault due to aging,… (more)

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nguyen, V. H. (2018). Model-based diagnosis and prognosis of induction motors under stator winding fault . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46022

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nguyen, Viet Hung. “Model-based diagnosis and prognosis of induction motors under stator winding fault .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46022.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nguyen, Viet Hung. “Model-based diagnosis and prognosis of induction motors under stator winding fault .” 2018. Web. 13 Dec 2019.

Vancouver:

Nguyen VH. Model-based diagnosis and prognosis of induction motors under stator winding fault . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46022.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nguyen VH. Model-based diagnosis and prognosis of induction motors under stator winding fault . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46022

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

17. Xu, Qianwen. Decentralized control and stability analysis for isolated microgrids .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46064

► In recent years, driven by the economic, environmental and sustainable incentives, there has been an increasing interest in the utilization of distributed generations (DGs) such… (more)

▼ In recent years, driven by the economic, environmental and sustainable incentives, there has been an increasing interest in the utilization of distributed generations (DGs) such as solar PV, wind turbines, fuel cells, microturbines, etc. A microgrid (MG), which combines DGs, energy storages (ESs) and a cluster of loads, is an enabling technology for high efficient and reliable utilization of DGs. MGs, especially operating at isolated mode, encounter many operational challenges to be addressed, including the critical demand-supply balance under the intermittent renewable DGs and the stability issues emerged from the high penetration of constant power loads. Conventionally, centralized control methods are adopted to solve the above issues, which require a centralized controller and a communication network to coordinate the operation of local controllers. However, these methods encounter high communication and computation burdens as well as the single point of failure issues. Considering the distributed nature of the DGs in a MG and to increase system reliability and scalability, decentralized control strategies without central controllers and communications are explored in this thesis, to deal with the issues of power balance and system stability. First, a decentralized dynamic power sharing strategy for hybrid energy storage system is proposed. Hybrid energy storage system provides an effective approach to compensate the power unbalance caused by the intermittency of renewable DGs and uncertainty of loads. To fully exploit the advantages of different energy storages in the hybrid energy storage system, it is desirable that the access-oriented ES (e.g. supercapacitor) compensates fast power fluctuations and the capacity-oriented ES (e.g. battery) provides the low-frequency power at steady state. Unlike the most existing methods with central controllers and communications, an extended droop control scheme with a virtual resistance droop controller and a virtual capacitance droop controller is proposed for hybrid battery/supercapacitor(SC) system to achieve dynamic power sharing in a decentralized manner. In addition, considering the bus voltage deviation issue resulted from the droop-based control approaches as well as the SC state-of-charge (SoC) recovery issue to ensure secure operation, a decentralized power management is further proposed to achieve autonomous dynamic power sharing, SC SoC recovery and bus voltage restoration at the same time. A design guideline is also developed to ensure the desired dynamics. Next, system stability issue is studied. Stable operation is a basic requirement for MGs. The high penetration of power electronic converter loads causes destabilizing effects in MGs, also known as the constant power load (CPLs) issue. Considering the increasing complexity and the requirement of system extension and reconfiguration of the MGs, a module-based approach is proposed for flexibly modeling and stability analysis. By this means, a complex system matrix can be easily integrated based on…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Xu, Q. (2018). Decentralized control and stability analysis for isolated microgrids . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46064

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xu, Qianwen. “Decentralized control and stability analysis for isolated microgrids .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46064.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xu, Qianwen. “Decentralized control and stability analysis for isolated microgrids .” 2018. Web. 13 Dec 2019.

Vancouver:

Xu Q. Decentralized control and stability analysis for isolated microgrids . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46064.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xu Q. Decentralized control and stability analysis for isolated microgrids . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46064

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

18. Liang, Zhipeng. In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46111

► Phase-locked loops (PLLs) have been successfully used as frequency synthesizers for decades in complementary metal–oxide–semiconductor (CMOS) transceivers for wireless communications. However, modern developments in communications… (more)

▼ Phase-locked loops (PLLs) have been successfully used as frequency synthesizers for decades in complementary metal–oxide–semiconductor (CMOS) transceivers for wireless communications. However, modern developments in communications require PLLs with wider loop bandwidth and lower in-band phase noise. High in-band phase noise leads to serious consequences in communications, such as degraded signal-to-noise ratio (SNR) and constellation diagram, resulting in low communication quality. Therefore, low PLL in-band phase noise is crucial to the overall transceiver performance, especially in future high-speed high-quality wireless communications. Unfortunately, frequency synthesizers based on conventional PLL structures are facing challenges because their in-band phase noise is often limited by the phase detectors and charge pumps. Noises from these components are amplified due to the structure of the conventional PLLs. Furthermore, PLL often needs to achieve short settling time for some communication standards, and has to provide multi-phase output in some transceiver architectures. Inspired by these requirements, this thesis aims to enhance PLL in-band phase noise performance while meeting other important requirements of future wireless communications in the multi-GHz band. As the background of this research, conceptual PLL fundamentals related to phase noise will be briefly discussed. According to these fundamentals, the in-band phase noise is usually limited by the phase detector and charge pump in analog PLLs, and by the time-to-digital converter (TDC) in digital PLLs. Therefore, the objective of this research is specifically to reduce the adverse impact from these components. When choosing an analog or a digital PLL structure, characteristics of the adopted fabrication technology have to be considered. As the CMOS technology development is facing physical and economic limitations, two promising future CMOS technologies have been predicted, i.e., the more-than-Moore technology and the more-Moore technology. In regard to PLL implementation, the more-than-Moore technology permits the use of CMOS with larger feature size so that high-performance analog PLLs can be designed with mature methods, while the more-Moore technology keeps using the finer processes in which digital PLLs may be more suitable due to their promising performance with technology scaling. Both PLL types will be important in future advanced CMOS technologies. Therefore, this research investigates in-band phase noise reduction techniques for both analog and digital PLLs. Firstly, in-band phase noise reduction technique for analog PLLs is investigated. With mature design and verification methods, analog PLLs have evolved and achieved low power consumption in the past years. However, conventional analog PLLs suffer from the high in-band noise from the phase detector and charge pump because noises from these components are amplified. To reduce such adverse impact, one of the most attractive structures is the fractional-N subsampling phase-locked loop…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Integrated circuits

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liang, Z. (2018). In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46111

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liang, Zhipeng. “In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46111.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liang, Zhipeng. “In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies .” 2018. Web. 13 Dec 2019.

Vancouver:

Liang Z. In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46111.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liang Z. In-band phase noise reduction techniques for phase-locked loops in advanced CMOS technologies . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46111

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

19. Seifozzakerini, Sajjad. Analysis of object and its motion in event-based videos .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46126

► In the recent years, a new generation of cameras sensitive to pixel intensity variation rather than the traditional pixel intensity value has been introduced. These… (more)

▼ In the recent years, a new generation of cameras sensitive to pixel intensity variation rather than the traditional pixel intensity value has been introduced. These cameras called Dynamic Vision Sensors (DVSs) have recently attracted significant research interest. Conventional camera captures the intensity of all pixels in the sensor and generate an entire image to produce a frame. This is then repeated at a fixed rate to produce a video stream. Being totally different with the old frame-based videos, the captured videos of Dynamic Vision Sensors are polarized events, i.e. points in 3-D spatio-temporal space, indicating the polarity, location and time properties of the pixels with variable intensities. When there is a variation in a pixel intensity, a polarized event is created in the form of a vector with three elements (t,x,y). t shows the instance of the variation and (x,y) defines the position of the pixel. Moreover, polarization of the event shows the direction of the change in the pixel intensity. For event-based videos, some algorithms have been proposed for object tracking, optical flow extraction, human action recognition, etc. Still there are many potential capabilities of these cameras that have not been used or explored. Extracting features of these videos requires a comprehensive understanding and novel procedures accordingly. We began our research by focusing on the existing algorithms for DVS videos. We found out that motional analysis and feature extraction are trending topics in DVS videos and we began to work on these topics. This thesis introduces two different approaches to objects' motion in event-based videos. Hough transform and edge detection are also performed in event-based videos as two important methods of feature extraction. This research work presents a novel framework for investigating the objects motion in event-based videos and extracting the edge information subsequently. In the event-based videos, the events normally occur in the moving edge areas. We consider the events as some points in the spatio-temporal space. Ignoring noise, for each small spatio-temporal window in a moving edge area, we expect all events to be on a 3-D plane. The orientation of this plane depends on both edge direction and velocity. By approximating the object boundary as a series of linear elements, we derive a procedure based on principal component analysis to estimate their orientation and speed. According to the well-known aperture problem in machine vision, the velocity estimated at this stage is the normal portion of the actual velocity since any displacement along the edge orientation cannot be recognized in a small spatio-temporal window. The normal velocities are utilized in a larger window which covers a whole object to estimate its actual velocity. We define a cost function based on the difference between actual normal velocities and calculated normal velocities at the previous stage. Minimization of this cost function results in an estimation of the actual velocity which is a useful parameter…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Control and instrumentation::Robotics; DRNTU::Engineering::Computer science and engineering::Computing methodologies::Image processing and computer vision

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Seifozzakerini, S. (2018). Analysis of object and its motion in event-based videos . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46126

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Seifozzakerini, Sajjad. “Analysis of object and its motion in event-based videos .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46126.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Seifozzakerini, Sajjad. “Analysis of object and its motion in event-based videos .” 2018. Web. 13 Dec 2019.

Vancouver:

Seifozzakerini S. Analysis of object and its motion in event-based videos . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46126.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Seifozzakerini S. Analysis of object and its motion in event-based videos . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46126

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

20. Liu, Tianchi. Clustering and semi-supervised classification with application to driver distraction detection .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46179

► Clustering and Semi-Supervised Classification (SSC) algorithms can make use of unlabeled training data and thus have the potential to alleviate labeling costs. For example, Extreme… (more)

▼ Clustering and Semi-Supervised Classification (SSC) algorithms can make use of unlabeled training data and thus have the potential to alleviate labeling costs. For example, Extreme Learning Machine (ELM) was recently extended to semi-supervised learning and clustering with promising performance. Meanwhile, it is either costly or infeasible to obtain labeled training samples in some real-world applications. The thesis investigates clustering and SSC algorithms with application to driver distraction detection. Firstly, the thesis investigates embedding-based clustering. The desirable properties of embedding are reviewed in the literature, e.g., preserving the intrinsic data structure and maximizing the class separability. To obtain better embedding for clustering, the thesis considers both properties together and develops a novel clustering algorithm referred to as ELM for Joint Embedding and Clustering (ELM-JEC). Experimental studies on a wide range of benchmark datasets have show that ELM-JEC is competitive with the related methods. Secondly, the thesis investigates graph-based clustering. One limitation of existing graph learning methods is that they adjust the graph based on either the original data or the linearly projected data, which may not effectively reveal the underlying low- dimensional structures. To address this limitation, this thesis develops dual data representations, i.e., the original data and their nonlinear embedding obtained via an ELM- based neural network, and uses them as the basis for graph learning. The resulting algorithm is named as clustering based on ELM and Constrained Laplacian Rank (ELM- CLR). The experimental results show that ELM-CLR outperforms other adaptive graph learning methods on most benchmark datasets. Finally, the thesis applies the proposed clustering algorithms, i.e., ELM-JEC and ELM- CLR, and several SSC algorithms to driver distraction detection. The clustering algorithms are used on unlabeled data to generate preliminary labels as reference to assist human experts in the labeling process. In terms of the clustering accuracy, both proposed clustering algorithms perform better or on par with the related algorithms. The best clustering accuracy is achieved by ELM-JEC. Moreover, the research question of “which type of SSC method is more suitable for driver distraction detection?” is answered by evaluating two popular types of semi-supervised methods on a real-world dataset of drivers’ eye and head movements. The experimental results show that the graph-based methods achieve twice the improvement by the low-density-separation based method. It has also been shown that 1) the graph-based methods reduce the required amount of labeled training data, and 2) the benefits in detection accuracy increase with the size of unlabeled datasets. Overall, the thesis contributes two novel clustering algorithms by making use of ELM- based embedding and discovers that 1) better clustering performance on some datasets is expected, if the embedding preserves the intrinsic local structure…

Subjects/Keywords: DRNTU::Engineering::Computer science and engineering::Computing methodologies::Pattern recognition; DRNTU::Engineering::Electrical and electronic engineering::Computer hardware, software and systems

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liu, T. (2018). Clustering and semi-supervised classification with application to driver distraction detection . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46179

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Tianchi. “Clustering and semi-supervised classification with application to driver distraction detection .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46179.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Tianchi. “Clustering and semi-supervised classification with application to driver distraction detection .” 2018. Web. 13 Dec 2019.

Vancouver:

Liu T. Clustering and semi-supervised classification with application to driver distraction detection . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46179.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu T. Clustering and semi-supervised classification with application to driver distraction detection . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46179

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

21. Li, Benliang. Cavity QED of superradiant phase transition in two dimensional materials .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46220

► This thesis consists of two parts. In the first part, the light-matter coupling between cyclotron transition and photon is theoretically investigated in some 2-D materials… (more)

▼ This thesis consists of two parts. In the first part, the light-matter coupling between cyclotron transition and photon is theoretically investigated in some 2-D materials such as the monolayer MoS2, graphene and monolayer black phosphorene (BP) systems. The results show that, in these 2-D materials, the ultrastrong light-matter coupling can be achieved at a high filling factor of Landau levels. Furthermore, we show that, in contrast to the case for conventional semiconductor resonators, the MoS2 system shows a vacuum instability. In monolayer MoS2 resonator, the diamagnetic term can still play an important role in determining magnetopolariton dispersion which is different from monolayer graphene system. The diamagnetic term arises from electron-hole asymmetry which indicates that electron-hole asymmetry can influence the quantum phase transition. Meanwhile, we show that, similar with some other 2D materials such as graphene and MoS2, the monolayer BP system shows a vacuum instability. However, in contrast with other 2D materials, the BP system displays a large energy gap between three branches of polaritons because of its strong anisotropic behavior in the eigenstates of the band structures. For the graphene system, we investigate the coupling of cyclotron transition and a multimode cavity described by a multimode Dicke model. This model exhibits a superradiant quantum phase transition, which we describe exactly in an effective Hamiltonian approach. The complete excitation spectrum in both the normal phase and superradiant phase regimes is given. At last, in contrast to the single mode case, multimode coupling of cavity photon and cyclotron transition can greatly reduce the critical vacuum Rabi frequency required for quantum phase transition, and dramatically enhance the superradiant emission by fast modulating the Hamiltonian. Our study provides new insights in cavity-controlled magneto-transport in these 2-D systems, which could lead to the development of polariton-based devices. The second part is a diversion from the main content of this thesis; readers who are not interested in foundational issues of physics can skip this part. For one charged quantum particle P moving in an electromagnetic vector potential created by some other charged particles, we can either use the framework of one particle quantum mechanics (OPQM) to calculate the evolutions of P, or we can treat this as an multi-particles problem in the framework of quantum field theory and calculate the evolution of P. These two methods need to be equavalent, i.e., they produce the same result for the evolution of P. One open question is how to describe the evolution of P within the framework of quantum field theory and show that these two methods yield the same result? In chapter 5, we are going to derive the OPQM from the quantum field theory, i.e., the quantum electrodynamics (QED) to be specific. We start with the discussions on the AB effect then raise a plausible interpretation within the QED framework. We provide a quantum treatment of the…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Li, B. (2018). Cavity QED of superradiant phase transition in two dimensional materials . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46220

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Li, Benliang. “Cavity QED of superradiant phase transition in two dimensional materials .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46220.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Li, Benliang. “Cavity QED of superradiant phase transition in two dimensional materials .” 2018. Web. 13 Dec 2019.

Vancouver:

Li B. Cavity QED of superradiant phase transition in two dimensional materials . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46220.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Li B. Cavity QED of superradiant phase transition in two dimensional materials . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46220

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

22. Lim, Jun Long. Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46223

► The microhole collapsing effect technique is a relatively simple fabrication process that produces Photonic Crystal Fiber (PCF) refractometer using modal interferometry in the range of… (more)

Subjects/Keywords: DRNTU::Science::Physics::Optics and light; DRNTU::Engineering::Electrical and electronic engineering

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APA (6^th Edition):

Lim, J. L. (2018). Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46223

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lim, Jun Long. “Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46223.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lim, Jun Long. “Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature .” 2018. Web. 13 Dec 2019.

Vancouver:

Lim JL. Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46223.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lim JL. Design and analysis of solid-core microstructured optical fiber sensors for sensing surrounding refractive index and surrounding temperature . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46223

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

23. Felis Dwiyasa. Machine learning for indoor positioning based on received signal strength .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46235

► Indoor positioning is a key technology enabler for various smart systems that require location-based optimization and automation. Despite its potential, the field of indoor positioning… (more)

▼ Indoor positioning is a key technology enabler for various smart systems that require location-based optimization and automation. Despite its potential, the field of indoor positioning faces numerous challenges in terms of accuracy, precision, computational complexity, power consumption, robustness, scalability, and cost. This thesis proposes machine learning approach to improve indoor positioning system that makes use of Received Signal Strength (RSS) positioning metric, in terms of accuracy, processing time, and robustness. We consider machine learning approach to be a potential alternative solution due to its ability to model nonlinear functions without a priori assumptions on the distribution of the data and the noise. We present several improvements in location fingerprinting approach with the objective of reducing the number of training data, improving robustness, and decreasing the length of processing time. We combine two existing location fingerprinting methods, which are Location Estimation using Model Tree (LEMT) and LANDMARC, to improve the accuracy and robustness of the location fingerprinting when training points are sparsely distributed. Performance evaluation shows that the proposed continuous-output modification of LEMT achieves 0.5 m to 2 m reduction in the 90th and 95th error percentile. LEMT method and its derivatives, however, have long training time and testing time because these methods rely on M5 model tree which is computationally intensive. The M5 model tree is used in LEMT to model the functional relationship between reference devices and tracking device. To address this problem, we propose the use of Extreme Learning Machine (ELM) regression model in place of M5 model tree to shorten the processing time. We found that incomplete data in the RSS fingerprint can either be imputed with a low RSS or filtered out, without negatively affecting the accuracy of ELM regression. With the use of ELM, the location fingerprinting method experiences 15 to 40 times improvement in training time and 6 to 10 times improvement in testing time, with accuracy degradation around 0.1 m to 0.5 m. Depending on the application involved, this may be considered reasonable or acceptable. We also evaluated the performance of the proposed methods using an open-access benchmark dataset containing no reference device, measured across 15 months. When reference devices are not present in the environment, we can use a subset of training fingerprints as reference data in place of the fingerprints of reference devices. Since we only use a subset of fingerprints, we reduced the amount of work in collecting repeated training data. Our proposed method produces superior accuracy across all months, indicating its ability to adapt to temporal variation despite having minimal amount of repeated training data, especially for the 11th month and beyond when the benchmark methods start to experience significant accuracy degradation.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Wireless communication systems; DRNTU::Engineering::Computer science and engineering::Computing methodologies::Artificial intelligence

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dwiyasa, F. (2018). Machine learning for indoor positioning based on received signal strength . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46235

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dwiyasa, Felis. “Machine learning for indoor positioning based on received signal strength .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46235.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dwiyasa, Felis. “Machine learning for indoor positioning based on received signal strength .” 2018. Web. 13 Dec 2019.

Vancouver:

Dwiyasa F. Machine learning for indoor positioning based on received signal strength . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46235.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dwiyasa F. Machine learning for indoor positioning based on received signal strength . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46235

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

24. Snehasish, Banerjee. Study of authentic and fictitious online reviews .

Degree: 2017, Nanyang Technological University

URL: http://hdl.handle.net/10220/46219

► This research investigates the ways in which differences between authentic and fictitious reviews on the Internet are related to users’ perceived review authenticity. To accomplish… (more)

Subjects/Keywords: DRNTU::Library and information science::Libraries::Information society; DRNTU::Business::Marketing::Consumer behavior; DRNTU::Business::Information technology::Electronic commerce; DRNTU::Library and information science::Libraries::Information retrieval and analysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Snehasish, B. (2017). Study of authentic and fictitious online reviews . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46219

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Snehasish, Banerjee. “Study of authentic and fictitious online reviews .” 2017. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46219.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Snehasish, Banerjee. “Study of authentic and fictitious online reviews .” 2017. Web. 13 Dec 2019.

Vancouver:

Snehasish B. Study of authentic and fictitious online reviews . [Internet] [Thesis]. Nanyang Technological University; 2017. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46219.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Snehasish B. Study of authentic and fictitious online reviews . [Thesis]. Nanyang Technological University; 2017. Available from: http://hdl.handle.net/10220/46219

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

25. Cometto, Mathieu. Use of carbon nanotubes for passive radio-frequency devices .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46256

► As devices get more connected and communication increase in density, new challenges arise. The usual frequency bands used are getting crowded by the number of… (more)

▼ As devices get more connected and communication increase in density, new challenges arise. The usual frequency bands used are getting crowded by the number of applications, and the relatively low working frequencies limit the available bandwidth and speed. Applications are now implemented in the GHz, but next generation devices shift towards higher frequencies into the millimetre band (30-300 GHz), seeking larger bandwidths, smaller devices and antenna size and improvement in spatial resolution. (High bitrate communications, Backhaul, radars, imaging, bio-sensors…) These emerging devices have a need for passive framework for feeding and supporting while keeping the efficiency high, the dimensions short and the bandwidth large. The problematic of this thesis is to devise an innovative way to answer those needs. Some solutions have of course emerged in the literature, and the plan here is to fork from those pre-existing results. Most solutions revolve around using vertically aligned micro/nano-structures to guide a wave or to reduce wave velocity. The idea is to introduce Vertically-Aligned Carbon Nanotube Forests (VA-CNT) into those designs, for they display inherently conductive anisotropy while improving from the previous solutions in terms of density and equivalent conductivity and ease of fabrication. As passive devices cover a broad range of devices, the focus will be on some of the simplest devices, to pave the way for this technology. In a first step a simple slow-wave micro-strip transmission line using VA-CNTs is considered, which showcases the possibility to reduce significantly wave velocity propagation in the line, thus reducing the dimensions without the use of high-k dielectrics. Work on the topic demonstrate significant size reduction of devices at a given frequency. In a second step, another type of transmission line is considered: Substrate integrated waveguides (SIW) and slow-wave SIW (SW-SIW). Waveguides large viii dimensions’ stop being a collateral at higher frequencies -with dimensions going bellow the millimetre- while exhibiting relatively better parameters per unit length than other propagation solutions. The feasibility of a SIW using VA-CNT forests is demonstrated through theoretical simulation and fabrication. A solution including a similar setup to the micro-strip line is investigated to assert the effects and possibility of slow-wave in waveguides using only bottom-up processes. Finally, as an extension of the problematic, some diverse and more complex topologies are considered such as filters, antenna arrays feedings or interposers.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cometto, M. (2018). Use of carbon nanotubes for passive radio-frequency devices . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46256

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cometto, Mathieu. “Use of carbon nanotubes for passive radio-frequency devices .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46256.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cometto, Mathieu. “Use of carbon nanotubes for passive radio-frequency devices .” 2018. Web. 13 Dec 2019.

Vancouver:

Cometto M. Use of carbon nanotubes for passive radio-frequency devices . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46256.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cometto M. Use of carbon nanotubes for passive radio-frequency devices . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46256

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

26. Rathnayaka Mudiyanselage Sooriya Bandara. Non-intrusive inductively coupled method for condition monitoring of electrical systems .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46254

► Off-line frequency response analysis method is widely adopted as a diagnostic technique for critical electrical system, for examples, winding deformation in transformer and stator’ winding… (more)

▼ Off-line frequency response analysis method is widely adopted as a diagnostic technique for critical electrical system, for examples, winding deformation in transformer and stator’ winding defects in induction motor. Usually, frequency response analysis detects abnormality of an electrical system by comparing its measured impedance’s frequency response with that of healthy one, which is new or has undergone a major overhaul. Off-line frequency response analysis requires shutdown of the system to be tested and therefore it lacks the real-time condition monitoring feature when the system is powered up and operates in its usual operating condition. Several on-line frequency response analysis methods have been reported but additional design and circuitries are necessary to facilitate excitation of signal and to measure the response. All these require some forms of direct electrical contacts to the system under test when it is powered by high-voltage, which can be a safety concern for personnel who handles the instrument on-site. Also, any additional circuitry to establish the electrical contact has a direct impact on the frequency response of the system under test, which can affect the accuracy of the diagnostic. This thesis proposes an on-line frequency response analysis technique that adopts a fully inductive coupling approach so that there is no direct electrical contact with the system under test, which eliminates the safety hazards. Also, the implementation is relatively easy and the installation can be done without switching off the power supply to the system. In addition, the calibration of the proposed method is relatively straightforward. Both the injecting and receiving probes can be calibrated off-line and therefore regular re-calibration of the probes without interrupting the operation of the monitored electrical system is possible, as opposed to other on-line methods that may require the monitored electrical system be switched off. The proposed method has relatively wide bandwidth that can be tailored to specific electrical system for best results. The theory behind the proposed method is described and the method validated experimentally. Using a transformer and an induction motor as system under test, on-line condition monitoring for early detection of defects is demonstrated.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bandara, R. M. S. (2018). Non-intrusive inductively coupled method for condition monitoring of electrical systems . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46254

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bandara, Rathnayaka Mudiyanselage Sooriya. “Non-intrusive inductively coupled method for condition monitoring of electrical systems .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46254.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bandara, Rathnayaka Mudiyanselage Sooriya. “Non-intrusive inductively coupled method for condition monitoring of electrical systems .” 2018. Web. 13 Dec 2019.

Vancouver:

Bandara RMS. Non-intrusive inductively coupled method for condition monitoring of electrical systems . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46254.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bandara RMS. Non-intrusive inductively coupled method for condition monitoring of electrical systems . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46254

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

27. Jiang, Wentao. Studies on the control of high-gain DC-DC boost converters .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46278

► The traditional dc-dc boost converter has been widely applied in industrial applications. However, due to the parasitic resistance of the inductor and the serious reverse-recovery… (more)

▼ The traditional dc-dc boost converter has been widely applied in industrial applications. However, due to the parasitic resistance of the inductor and the serious reverse-recovery problem, the voltage gain of this converter is very limited. To solve this problem, many high voltage gain dc-dc boost converters have been proposed in the last decade. The high voltage gain dc-dc boost converters can be roughly separated as isolated converters and non-isolated converters. Since most of the isolated converters suffer from large amount of power losses caused by the leakage current problem, the non-isolated converters are more preferred in applications where electrical isolation is not necessary. Since the non-isolated high voltage gain dc-dc boost converters are generally high-order non-minimum phase systems, it is more difficult to regulate these converters as compared to regulating their traditional counterpart. In this thesis, some studies on the control aspects of such non-isolated high voltage gain dc-dc boost converters are presented. Firstly, the study on how to select the most suitable state variables to design the current-mode controller for the high voltage gain dc-dc converter is presented. For the current-mode control technique, the measurement of the inductor current for feedback purpose is necessary. However, some of the high voltage gain converters, such as the hybrid-type dc-dc boost converter, contain two or more inductors. As such, the issues such as which inductor current is more suitable for the design of the controller should be answered. To address this, a comparative study of the adaptive current-mode controllers for the hybrid-type high-order dc-dc boost converter was carried out. The Routh-Hurwitz stability criterion was used to determine the most suitable inductor current for the controller design. Some simulation as well as experimental results are also presented to verify the theoretical conclusions. Next, the problem of regulation of high-order dc-dc converters using least number of state variables for feedback purposes is addressed. To this end, three output feedback control laws for various non-isolated high voltage gain dc-dc boost-type converters are proposed. In these control laws, only the converter output voltage is required for the feedback purposes. This feature results in that, these control laws are very suitable for the applications where there is a cost limit or power density constraint to accommodate the current sensor. Initially, a voltage-mode controller for a dc-dc multilevel boost converter is presented. Unlike some of the existing voltage-mode controllers for the high-order dc-dc converters, the selection of the controller gains of the proposed controller does not rely on a trial and error approach. Since the proposed controller uses the new structure, the frequency domain method could be used to select the appropriate values for the controller gains to ensure robust stability. As such, it is easier to achieve the desired robust control performance. Next, the…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Power electronics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jiang, W. (2018). Studies on the control of high-gain DC-DC boost converters . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46278

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jiang, Wentao. “Studies on the control of high-gain DC-DC boost converters .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46278.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jiang, Wentao. “Studies on the control of high-gain DC-DC boost converters .” 2018. Web. 13 Dec 2019.

Vancouver:

Jiang W. Studies on the control of high-gain DC-DC boost converters . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46278.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jiang W. Studies on the control of high-gain DC-DC boost converters . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46278

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

28. Teoh, Tharsis Ghim Han. Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46273

► Electrification of urban freight transport is a key strategy in decarbonizing the transport sector. However, battery electric vehicles (BEV) for logistics purposes are still disadvantaged… (more)

▼ Electrification of urban freight transport is a key strategy in decarbonizing the transport sector. However, battery electric vehicles (BEV) for logistics purposes are still disadvantaged in comparison to diesel vehicles, due to their limited driving range, reduced payload capacity, and high purchase prices. Evaluation studies can play a role to inform decision makers and stakeholders about the advantages of BEVs and the best strategies to successfully promote the technology. Existing evaluation studies often reduce vehicle requirements to simple travel distances, which has severe consequences for the validity of their recommendations. Existing studies also do not incorporate a wider conceptual solution space of electric mobility, particularly, the use of opportunity charging. The evaluation framework proposed here deals with the gaps in existing studies, as well as proposes a novel method to evaluate electric mobility for urban freight transport in terms of operational, financial, and environmental suitability. The study uses a comparative case analysis on six case studies of different urban freight transport operations in Singapore. Using information gathered from interviews, a detailed vehicle activity model is developed. For each case, scenarios are built, which primarily show how distinct types of opportunity charging and charging technology can be integrated into the logistics operations. A BEV parametric model is used to adapt vehicle parameters (i.e. battery capacity and vehicle weight) to operational requirements based on the results of the vehicle activity model. Financial suitability is evaluated based on the lifecycle cost analysis of owning and using the electric fleet, while the environmental suitability is analysed based on the well-to-wheels carbon dioxide emissions. The results show a varying degree of suitability of BEVs for the different urban freight transport cases. They point to a complex set of factors that have profound influences especially on financial suitability. Opportunity charging strategies were found to be the best ways to improve both financial and environmental suitability. The sensitivity of the suitability indicators to the assumptions in the vehicle activity models shows the need for detailed and well-tested models to accurately evaluate the suitability of BEV to urban freight transport operations. It also shows the need for further research into designing systems and business models that support opportunity charging, since it was found to be the most influential factor in increasing the suitability of BEVs in the urban freight transport sector.

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering::Electric power

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Teoh, T. G. H. (2018). Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46273

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Teoh, Tharsis Ghim Han. “Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46273.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Teoh, Tharsis Ghim Han. “Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework .” 2018. Web. 13 Dec 2019.

Vancouver:

Teoh TGH. Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46273.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Teoh TGH. Suitability of battery electric vehicles and opportunity charging for urban freight transport : an evaluation framework . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46273

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

29. Zhang, Hailiang. Multicore fibers for sensing applications .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46327

► Multicore fibers (MCFs) are optical fibers which have several cores integrated into a common cladding. As one type of space-division multiplexing, MCFs have been widely… (more)

▼ Multicore fibers (MCFs) are optical fibers which have several cores integrated into a common cladding. As one type of space-division multiplexing, MCFs have been widely investigated in optical communication to improve the data capacity limit. Due to the intrinsic advantages such as small size, well-defined core separation, improved isothermal behaviour, light weight, immunity to electromagnetic interference, MCFs have also attracted extensive interests for optical sensing applications. This thesis focuses on investigating and fabricating MCF-based sensors with high performances by post-processing techniques such as inscribing gratings or introducing helical structures into the MCFs. In this thesis, we first review the background knowledge and development of MCF-based sensors. And then we detail the working principles, fabrication methods and experimental results of three sensors based on a heterogeneous MCF. The first one is a directional bending sensor based on a heterogeneous MCF with fiber Bragg gratings (FBGs). To date, several types of sensors based on FBGs inscribed in homogeneous MCFs have been reported. However, due to the homogeneous properties of the multiple cores, simultaneous interrogation of the FBGs in the multiple cores demands high precision and cumbersome alignment with, for example, a coupler and a ball lens, or customized and complicated fan-out devices. Therefore, to realize an easier interrogation of the FBGs in different cores, we propose to inscribe FBGs in heterogeneous MCFs. As the heterogeneous MCFs have non-identical cores, FBGs with different resonant wavelengths can be written simultaneously into the multiple cores in only one process with the scanned phase mask method. The MCF we used has a center core and six identical outer cores located respectively at the corners of a regular hexagon. The refractive index of the center core is a little lower than that of the outer cores. Due to the refractive index difference between the center core and outer cores, the FBGs with obviously different central wavelengths can be measured by only splicing a segment of a multimode fiber (MMF) between the MCF and the lead-in single mode fiber (SMF). The curvature sensitivity of the FBG in the outer core depends on the bending orientation in the form of a sine function. The maximum linear curvature sensitivity is about 0.128 nm/m-1. The proposed sensor offers advantages of flexibility in fabrication, simple interrogation, and capability of eliminating the cross-sensitivity to temperature or externally applied axial strain. The second one is a highly sensitive strain sensor based on a helical structure (HS) fabricated in the MCF. The MCF was locally twisted into an HS permanently by a CO2 laser splicing system and then spliced between two short sections of MMFs to construct an in-line Mach-Zehnder interferometer. In the region of the HS, the outer cores were deformed into helical cores while the center core was kept straight. Due to the HS, a maximum strain sensitivity as high as −61.8pm/με was…

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, H. (2018). Multicore fibers for sensing applications . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46327

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Hailiang. “Multicore fibers for sensing applications .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46327.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Hailiang. “Multicore fibers for sensing applications .” 2018. Web. 13 Dec 2019.

Vancouver:

Zhang H. Multicore fibers for sensing applications . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46327.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang H. Multicore fibers for sensing applications . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46327

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nanyang Technological University

30. Low, Qiong Wei. Low power AC-DC converters for wireless power transfer application .

Degree: 2018, Nanyang Technological University

URL: http://hdl.handle.net/10220/46333

► Wireless power transfer (WPT) technology is gaining its popularity in recent years, which is largely motivated by extensive research work. It is attractive as the… (more)

Subjects/Keywords: DRNTU::Engineering::Electrical and electronic engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Low, Q. W. (2018). Low power AC-DC converters for wireless power transfer application . (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10220/46333

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Low, Qiong Wei. “Low power AC-DC converters for wireless power transfer application .” 2018. Thesis, Nanyang Technological University. Accessed December 13, 2019. http://hdl.handle.net/10220/46333.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Low, Qiong Wei. “Low power AC-DC converters for wireless power transfer application .” 2018. Web. 13 Dec 2019.

Vancouver:

Low QW. Low power AC-DC converters for wireless power transfer application . [Internet] [Thesis]. Nanyang Technological University; 2018. [cited 2019 Dec 13]. Available from: http://hdl.handle.net/10220/46333.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Low QW. Low power AC-DC converters for wireless power transfer application . [Thesis]. Nanyang Technological University; 2018. Available from: http://hdl.handle.net/10220/46333

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Open Access Theses and Dissertations