You searched for subject:(high frequency).
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1.
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka, Toshiaki.
Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用.
Degree: 博士（医学）, 2014, Nara Medical University / 奈良県立医科大学
URL: http://hdl.handle.net/10564/2696 
► High-frequency audiometry has the potential to detect hearing impairment at its early stage. However, several problems prevent the clinical application of high-frequency audiometry. In this…
(more)
▼ High-frequency audiometry has the potential to detect hearing impairment at its early stage. However, several problems prevent the clinical application of high-frequency audiometry. In this study, the dispersion and left-right difference in the high-frequency sensitivity were investigated in normal hearing volunteers. In our results, the difference between the left and right ears varied only slightly among individuals or age groups, while dispersion of hearing threshold values became marked with an increase in frequency. The results suggest that the measurement of left-right difference in high-frequency sensitivity may be useful for the evaluation of unilateral impairment. To investigate this usefulness, the left-right differences were measured in the patients complaining of unilateral cochlear symptom with normal hearing. Considering the results of normal hearing, we determined that abnormal left-right difference in high-frequency sensitivity was over 20 dB. In 12 patients with unilateral tinnitus, 7 showed left-right differences, and 6 had tinnitus in the ear with increased thresholds. Our results suggested a relationship between tinnitus with normal hearing and hearing impairment in the high-frequency range.
博士（医学）・乙1335号・平成26年3月17日
Subjects/Keywords: high frequency audiometry; high frequency sound; tinnitus
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APA (6th Edition):
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka, T. (2014). Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用. (Thesis). Nara Medical University / 奈良県立医科大学. Retrieved from http://hdl.handle.net/10564/2696
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka, Toshiaki. “Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用.” 2014. Thesis, Nara Medical University / 奈良県立医科大学. Accessed March 06, 2021.
http://hdl.handle.net/10564/2696.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka, Toshiaki. “Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用.” 2014. Web. 06 Mar 2021.
Vancouver:
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka T. Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用. [Internet] [Thesis]. Nara Medical University / 奈良県立医科大学; 2014. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10564/2696.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Uratani, Yuka; Nishimura, Tadashi; Ohara, Nari; Yamanaka T. Left-right difference in high frequency sensitivity : application for unilateral cochlear disorder evaluation. : 高周波聴力の左右差 : 一側性の蝸牛障害の評価への応用. [Thesis]. Nara Medical University / 奈良県立医科大学; 2014. Available from: http://hdl.handle.net/10564/2696
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
2.
Martinelli, Sheri L.
A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics.
Degree: PhD, Applied Mathematics, 2012, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:297523/
► Computer models for underwater sound propagation often rely on ray tracing to obtain solutions to the high frequency wave equation. While adequate for large scale…
(more)
▼ Computer models for underwater sound propagation often
rely on ray tracing to obtain solutions to the
high frequency wave
equation. While adequate for large scale results in deep water
environments, ray tracing has drawbacks that limit its reliability
for simulations involving multiple boundary interactions and in
studies concerning the effects of unmodeled physical processes.
This work presents the development and application of the level set
method to the
high frequency wave equation with the intent of
providing a framework for wavefront propagation in underwater
acoustics as a valuable alternative to ray tracing.
Level set methods are generic, computational models for
solving dynamic interface problems. The model regularizes problems
which exhibit behavior that is difficult to capture numerically in
physical space by posing the problem in the higher-dimensional
phase space. A relevant example is the behavior of
self-intersecting wavefronts; in physical space, such solutions are
multiple-valued. The level set method represents the interface
implicitly as the zero level set of some function in the phase
space, then propagates the surface according to a problem-dependent
velocity field. Although the problem is posed in a higher
dimensional space, the quantities of interest are local to the
interface. Thus the computational burden may be reduced by solving
the level set equations only in a neighborhood of the zero level
set.
The behavior of solutions at a reflecting boundary motivates
the application of WENO methods, which are known to perform well on
problems involving shocks. Since WENO methods are complicated to
implement on irregular grids, two methods for applying reflection
boundary conditions at an interface embedded within a Cartesian
grid are proposed. In addition, this work develops a method for
computing spreading loss via a semi-Lagrangian approach using the
wavefronts provided by the level set solutions. A final topic is
the application of a stochastic collocation method to study the
effect of random perturbations in the wave speed on the wavefront
propagation algorithm. Verification against a full wave equation
solver and ray tracing software shows that the resulting method
provides accurate wavefront information in the presence of
multi-path propagation.
Advisors/Committee Members: Hesthaven, Jan (Director), Shu, Chi-Wang (Reader), Siegmann, William (Reader).
Subjects/Keywords: high frequency acoustics
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APA ·
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MLA ·
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CSE |
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APA (6th Edition):
Martinelli, S. L. (2012). A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:297523/
Chicago Manual of Style (16th Edition):
Martinelli, Sheri L. “A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics.” 2012. Doctoral Dissertation, Brown University. Accessed March 06, 2021.
https://repository.library.brown.edu/studio/item/bdr:297523/.
MLA Handbook (7th Edition):
Martinelli, Sheri L. “A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics.” 2012. Web. 06 Mar 2021.
Vancouver:
Martinelli SL. A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics. [Internet] [Doctoral dissertation]. Brown University; 2012. [cited 2021 Mar 06].
Available from: https://repository.library.brown.edu/studio/item/bdr:297523/.
Council of Science Editors:
Martinelli SL. A Level-Sets-Based Wavefront Propagation Method for
Underwater Acoustics. [Doctoral Dissertation]. Brown University; 2012. Available from: https://repository.library.brown.edu/studio/item/bdr:297523/
Penn State University
3.
Zhang, Haolun.
High Frequency Mri Rf Coil Design.
Degree: 2013, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/17444
► MRI is one of the major imaging techniques in the daily clinical routine. A major trend in clinical and research MRI systems is the increase…
(more)
▼ MRI is one of the major imaging techniques in the daily clinical routine. A major trend in clinical and research MRI systems is the increase in resolution through using higher static magnetic fields. The static B_0 magnetic field strength of clinical scanners ranges from 0.5 to 3 T, and the corresponding RF signal frequencies (proportional to the magnetic field,B_1) for protons are 21 MHz and 128 MHz, respectively. Penn State has a 14T and 20T system with operating proton frequencies of 600 MHz and 850 MHz, respectively. By moving toward the higher frequencies, the design of MRI detectors called RF resonators become more challenging.
In this work RF resonators for
high-field MRI applications operating at 600 MHz and 850 MHz are designed and constructed. Simulations using a commercial finite-difference-time-domain code CST (Computer Simulation Technology) are acquired to get the circuit capacitance values and the B_1 field generated coil. RF resonators are comprised of capacitors and inductive coils. The capacitors provide matching and tuning functions so that the resonant
frequency of the loaded coil remains at the Larmor
frequency of 600MHz and 850 MHz. The coils are used for imaging after they are successfully fabricated.
Advisors/Committee Members: Michael T Lanagan, Thesis Advisor/Co-Advisor, Thomas Neuberger, Thesis Advisor/Co-Advisor, Jian Xu, Thesis Advisor/Co-Advisor.
Subjects/Keywords: high frequency; mri; rf coil
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APA (6th Edition):
Zhang, H. (2013). High Frequency Mri Rf Coil Design. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17444
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zhang, Haolun. “High Frequency Mri Rf Coil Design.” 2013. Thesis, Penn State University. Accessed March 06, 2021.
https://submit-etda.libraries.psu.edu/catalog/17444.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhang, Haolun. “High Frequency Mri Rf Coil Design.” 2013. Web. 06 Mar 2021.
Vancouver:
Zhang H. High Frequency Mri Rf Coil Design. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Mar 06].
Available from: https://submit-etda.libraries.psu.edu/catalog/17444.
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. High Frequency Mri Rf Coil Design. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/17444
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Toronto
4.
Jeon, Yoontae.
High Frequency Trading in a Regime-switching Model.
Degree: 2010, University of Toronto
URL: http://hdl.handle.net/1807/25636
► One of the most famous problem of finding optimal weight to maximize an agent's expected terminal utility in finance literature is Merton's optimal portfolio problem.…
(more)
▼ One of the most famous problem of finding optimal weight to maximize an agent's expected terminal utility in finance literature is Merton's optimal portfolio problem. Classic solution to this problem is given by stochastic Hamilton-Jacobi-Bellman Equation where we briefly review it in chapter 1. Similar idea has found many applications in other finance literatures and we will focus on its application to the high-frequency trading using limit orders in this thesis. In [1], major analysis using the constant volatility arithmetic Brownian motion stock price model with exponential utility function is described. We re-analyze the solution of HJB equation in this case using different asymptotic expansion. And then, we extend the model to the regime-switching volatility model to capture the status of market more accurately.
MAST
Advisors/Committee Members: Jaimungal, Sebastian, Mathematics.
Subjects/Keywords: High Frequency; Regime Switching; 0405
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APA (6th Edition):
Jeon, Y. (2010). High Frequency Trading in a Regime-switching Model. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/25636
Chicago Manual of Style (16th Edition):
Jeon, Yoontae. “High Frequency Trading in a Regime-switching Model.” 2010. Masters Thesis, University of Toronto. Accessed March 06, 2021.
http://hdl.handle.net/1807/25636.
MLA Handbook (7th Edition):
Jeon, Yoontae. “High Frequency Trading in a Regime-switching Model.” 2010. Web. 06 Mar 2021.
Vancouver:
Jeon Y. High Frequency Trading in a Regime-switching Model. [Internet] [Masters thesis]. University of Toronto; 2010. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1807/25636.
Council of Science Editors:
Jeon Y. High Frequency Trading in a Regime-switching Model. [Masters Thesis]. University of Toronto; 2010. Available from: http://hdl.handle.net/1807/25636
5.
Bajor, Eric J.
High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment.
Degree: MS, Mechanical Engineering, 2015, University of New Hampshire
URL: https://scholars.unh.edu/thesis/5
► Seafloor backscatter collected with high-frequency (> 100 kHz) hydrographic echosounders has become an important aspect of seafloor characterization for benthic ecologists and other scientists.…
(more)
▼ Seafloor backscatter collected with
high-
frequency (> 100 kHz) hydrographic echosounders has become an important aspect of seafloor characterization for benthic ecologists and other scientists. The mechanisms that control acoustic scattering at these
high frequencies are not completely understood, although surficial roughness and the presence of discrete particles (e.g., shell hash) are likely contributors. To further our understanding of the impact these mechanisms have on seafloor scattering, broadband (100-250 kHz) acoustic measurements were taken at a grazing angle of 45° in a shallow-water, sandy environment with a known presence of shell hash. Stereo imagery was collected simultaneously to quantify the surficial roughness of the seafloor. Sediment samples were also collected at the site of the experiment to quantitatively analyze the content of shell hash. Backscatter observations between the frequencies of 170 kHz – 250 kHz showed a minimal increase in amplitude with increasing
frequency while observations at lower frequencies between 100 kHz – 150 kHz showed an apparent increase in amplitude relative to increasing
frequency. Data to model comparisons of the
frequency dependence of seafloor backscatter were made to both roughness and discrete particle scattering models indicating neither model is a good descriptor of the seafloor backscatter response.
Advisors/Committee Members: Thomas C. Webber, Larry A. Mayer, Diane L. Foster.
Subjects/Keywords: backscatter; estuarine; high-frequency
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APA (6th Edition):
Bajor, E. J. (2015). High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment. (Thesis). University of New Hampshire. Retrieved from https://scholars.unh.edu/thesis/5
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bajor, Eric J. “High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment.” 2015. Thesis, University of New Hampshire. Accessed March 06, 2021.
https://scholars.unh.edu/thesis/5.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bajor, Eric J. “High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment.” 2015. Web. 06 Mar 2021.
Vancouver:
Bajor EJ. High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment. [Internet] [Thesis]. University of New Hampshire; 2015. [cited 2021 Mar 06].
Available from: https://scholars.unh.edu/thesis/5.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bajor EJ. High-Frequency Broadband Seafloor Backscatter in a Sandy Estuarine Environment. [Thesis]. University of New Hampshire; 2015. Available from: https://scholars.unh.edu/thesis/5
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Southern California
6.
Kang, Bong Jin.
High-frequency ultrasound array-based imaging system for
biomedical applications.
Degree: PhD, Biomedical Engineering, 2015, University of Southern California
URL: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/562902/rec/3182
► High frequency ultrasound imaging, capable of achieving superior spatial resolution in real-time, has been shown to be useful for imaging and visualizing blood flow in…
(more)
▼ High frequency ultrasound imaging, capable of
achieving superior spatial resolution in real-time, has been shown
to be useful for imaging and visualizing blood flow in
ophthalmology, dermatology, and small animal research. The
utilization of
high frequency array-based imaging system can
alleviate the limitations of the systems with single element
transducers. This dissertation presents an investigation of
high
frequency array-based imaging system and its potential biomedical
applications. The system is capable of B-mode imaging, PW-Doppler,
color Doppler imaging, and RF data acquisition. Three different
types of
high frequency (30 MHz 256-element linear, 20 MHz
192-element convex, and 20 MHz 48-element phased) array transducers
were implemented on the array-based imaging system. The system was
also utilized for ophthalmic imaging: 30 MHz linear array for
anterior segment and 20 MHz convex array for both anterior and
posterior segments imaging of the eye. Anatomical structures, such
as cornea, iris, ciliary body, lens, and retina, choroid, and
sclera layers were identified. The
high frequency PW Doppler and
micro-ECG were integrated to assess the ventricular diastolic
function during heart regeneration of the adult zebrafish.
Synchronized PW Doppler with ECG signals confirmed the A-wave in
response to atrial contraction (P wave in ECG), E-wave in response
to ventricular relaxation (T wave in ECG), and ventricular outflow
in response to ventricular contraction (QRS complex in ECG). The
E/A ratio is less than 1 in zebrafish at baseline, reflecting a
higher active filling (A-wave) than passive filling (E-wave)
velocities in the two-chamber heart system.
High frequency dual
mode pulsed-wave Doppler imaging, which provides both tissue
Doppler and Doppler flow in a same cardiac cycle, was implemented
on the array-based imaging system for monitoring the functional
regeneration of adult zebrafish hearts. In the in vivo study of
zebrafish, both tissue Doppler and flow Doppler signals were
simultaneously obtained and the synchronized valve motions with the
blood flow were identified. In the longitudinal study on the
zebrafish heart regeneration, the parameters for diagnosing the
diastolic dysfunction were measured, and the type of diastolic
dysfunction caused by the amputation was found to be similar to the
restrictive filling. The diastolic function was fully recovered
within four weeks post-amputation.
High frequency color Doppler
imaging was implemented on the array-based imaging system and
evaluated by the flow phantom and adult zebrafish in vivo studies.
In the flow phantom study, constant velocity with opposite flow
directions was detected utilizing color Doppler imaging. Also,
color Doppler imaging could be used to monitor blood flows inside
adult zebrafish heart and flow directions were clearly identified
by the color-coded images.
Advisors/Committee Members: Shung, Kirk Koping (Committee Chair), Yen, Jesse T. (Committee Member), Kuo, C. C. Jay (Committee Member).
Subjects/Keywords: high-frequency ultrasound; high-frequency ultrasound array-based imaging
system; high-frequency ultrasound pulsed-wave Doppler; high-frequency ultrasound color Doppler
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APA ·
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Manager
APA (6th Edition):
Kang, B. J. (2015). High-frequency ultrasound array-based imaging system for
biomedical applications. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/562902/rec/3182
Chicago Manual of Style (16th Edition):
Kang, Bong Jin. “High-frequency ultrasound array-based imaging system for
biomedical applications.” 2015. Doctoral Dissertation, University of Southern California. Accessed March 06, 2021.
http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/562902/rec/3182.
MLA Handbook (7th Edition):
Kang, Bong Jin. “High-frequency ultrasound array-based imaging system for
biomedical applications.” 2015. Web. 06 Mar 2021.
Vancouver:
Kang BJ. High-frequency ultrasound array-based imaging system for
biomedical applications. [Internet] [Doctoral dissertation]. University of Southern California; 2015. [cited 2021 Mar 06].
Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/562902/rec/3182.
Council of Science Editors:
Kang BJ. High-frequency ultrasound array-based imaging system for
biomedical applications. [Doctoral Dissertation]. University of Southern California; 2015. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/562902/rec/3182
University of New South Wales
7.
Tria, Lew Andrew.
Modelling and design of planar PCB transformers for high-frequency DC-DC converters.
Degree: Electrical Engineering & Telecommunications, 2017, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/59153
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48544/SOURCE02?view=true
► The demand for high density power supplies has been increasing through the years. The most common trend in achieving high power density is to use…
(more)
▼ The demand for
high density power supplies has been increasing through the years. The most common trend in achieving
high power density is to use
high frequency switching which results in smaller component size. However, for the magnetic components, operation at
high frequencies leads to increased conductor losses due to skin and proximity effects. The use of planar transformers on printed circuit boards (PCB) can mitigate this problem. The thinner and wider conductors of PCBs assist in reducing
high-
frequency losses. With larger surface areas, planar transformers also offer better thermal performance than conventional wire-wound magnetics. In this thesis, research activities to further the technology of planar PCB transformer are presented. These research activities are aimed at improving the modelling, design and utilization of planar PCB transformers for
high-
frequency power converters. A new non-linear model of planar PCB magnetics was developed to model the winding loss, core loss, and saturation characteristics. The developed model can be implemented in a circuit simulation package which can be used to predict the performance of the PCB transformer in a power converter system. The model was also used to derive the
high-
frequency electrical parameters of a PCB transformer. The model-derived parameters were proven to be comparable to LCR measurement and results obtained using finite element analysis. A stochastic method of estimating the electric parameters of a PCB transformer, based on differential evolution, was also developed. The developed method was shown to be a potential alternative to resource-intensive numerical methods. Existing guidelines for the design of PCB transformers are evaluated using finite element analysis and validated in a prototype transformer. Results of the evaluation show that the existing guidelines result in over-design of PCB transformers. For higher power applications, using the
high-
frequency advantage of PCB transformers, methods to implement multiple planar PCB transformers, including the concept of matrix transformer, are presented and compared. Through the evaluated design guidelines, prototypes of multiple core transformers were fabricated and characterised in a power converter system. Result of the comparison of the different implementations showed that the trade-off is between
high-
frequency losses and thermal dissipation.
Advisors/Committee Members: Zhang, Daming, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW, Fletcher, John, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW.
Subjects/Keywords: PCB transformers; High-frequency magnetics
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APA ·
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Manager
APA (6th Edition):
Tria, L. A. (2017). Modelling and design of planar PCB transformers for high-frequency DC-DC converters. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/59153 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48544/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Tria, Lew Andrew. “Modelling and design of planar PCB transformers for high-frequency DC-DC converters.” 2017. Doctoral Dissertation, University of New South Wales. Accessed March 06, 2021.
http://handle.unsw.edu.au/1959.4/59153 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48544/SOURCE02?view=true.
MLA Handbook (7th Edition):
Tria, Lew Andrew. “Modelling and design of planar PCB transformers for high-frequency DC-DC converters.” 2017. Web. 06 Mar 2021.
Vancouver:
Tria LA. Modelling and design of planar PCB transformers for high-frequency DC-DC converters. [Internet] [Doctoral dissertation]. University of New South Wales; 2017. [cited 2021 Mar 06].
Available from: http://handle.unsw.edu.au/1959.4/59153 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48544/SOURCE02?view=true.
Council of Science Editors:
Tria LA. Modelling and design of planar PCB transformers for high-frequency DC-DC converters. [Doctoral Dissertation]. University of New South Wales; 2017. Available from: http://handle.unsw.edu.au/1959.4/59153 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48544/SOURCE02?view=true
University of Waterloo
8.
Khanali, Mahdi.
Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers.
Degree: 2017, University of Waterloo
URL: http://hdl.handle.net/10012/12368
► The significant global growth in renewable energy production has led to increasing concerns about the problems associated with electrical equipment in power plants connected with…
(more)
▼ The significant global growth in renewable energy production has led to increasing concerns about the problems associated with electrical equipment in power plants connected with this type of energy. The crucial electrical components of renewable energy generation are step-up transformers, with respect to which, gassing problems and premature insulation failures have been extensively reported in recent years. One of the factors related to the reported problems is the presence of high-frequency high-dV/dt voltages that are created by switching operations in wind energy plants. Addressing this challenge necessitates the investigation of transformer insulation systems under high-dV/dt pulse voltages.
This thesis presents research undertaken in order to examine the performance of wind turbine step-up transformers under distorted voltages, with consideration of internal resonance phenomena and high-frequency dielectric effects. To evaluate the effect of distorted voltage on the acceleration of the ageing process in transformers, model transformers have been aged under distorted power converter voltage as well as under pure sinusoidal power grid voltage. Relevant parameters are monitored as indicators of the condition of the transformer insulation, and the results are compared throughout the ageing period. In addition, to study the transformer behavior under high-frequency high-dV/dt voltages, a detailed high-frequency model is necessary. High frequency modeling of large power transformers is complex and time-consuming due to their sizes. Therefore, as an alternative approach, this work proposes a modeling method that considers the high-frequency behavior of a scale down model transformer, and then relates it to the behavior of the actual size transformer. To verify the proposed modelling method, an experimental study investigates the correlations between the frequency responses of the two model transformers of different power ratings and sizes. Comparison of the frequency responses of the scaled and original transformers validates the proposed approach of scaling transformers for high-frequency study.
High-frequency measurements are performed on an actual wind turbine transformer to represent a linear wideband black-box model of wind turbine step-up transformer in an electromagnetic transient study. Using the simulation results for switching impulsive waveforms imposed on wind turbine transformers due to the adjacent breakers operations, this work evaluates the effects of impulsive voltage parameters such as rate of rise and repetition frequency on inception voltage and intensity of partial discharge, generally assumed to be the main long-term cause of insulation deterioration. Partial discharge parameter measurement under high-dV/dt voltages is challenging due to interferences from fast oscillations, and difficulties of PD energy measurements. To avoid such issues, which are related to electromagnetic detection methods under pulse energization, this work uses a chemical approach to compare PD, based on the rate of…
Subjects/Keywords: Transformer; high frequency; Insulation; High frequency effects; Frequency response analysis; Renewable energy
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APA (6th Edition):
Khanali, M. (2017). Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/12368
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Khanali, Mahdi. “Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers.” 2017. Thesis, University of Waterloo. Accessed March 06, 2021.
http://hdl.handle.net/10012/12368.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Khanali, Mahdi. “Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers.” 2017. Web. 06 Mar 2021.
Vancouver:
Khanali M. Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10012/12368.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Khanali M. Effects of Distorted Voltages on the Performance of Renewable Energy Plant Transformers. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/12368
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
9.
Sridharan, Rajasekaran.
Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete.
Degree: MS, Construction Management, 2011, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-8025
► The concrete maturity method can be utilized to determine in situ strength of concrete. It uses the temperature of concrete to determine a maturity index…
(more)
▼ The concrete maturity method can be utilized to determine in situ strength of concrete. It uses the temperature of concrete to determine a maturity index that can then be used to determine strength of concrete. However, monitoring the concrete temperature using thermocouples brings up a wiring issue, which is not advisable in an equipment and human intensive area like a construction site. One of the ways to get around this wiring issue is to use Radio
Frequency Identification (RFID) technology, which is capable of transmitting information wirelessly. Previous research implemented using ultra
high frequency RFID tags embedded in fresh concrete found that water could be the impediment for transmitting RFID signal from within concrete during early stages of curing. From literature it was found that lower the
frequency, better the chances of the wave penetrating water. The objective of the research was to figure out whether the
frequency of RFID tags has any relationship with the readability of RFID tags embedded in fresh concrete. For this investigation, low
frequency,
high frequency, and ultra
high frequency RFID tags were tested within fresh concrete to see any difference between tags in terms of transmitting information. This experiment was carried out in a controlled space to reduce the number of variables affecting the experiment outcome. The low
frequency,
high frequency, and ultra
high frequency RFID tags were placed within 2 in x 3 in x 2 in wooden formwork at a depth of 4 in, 8 in, and 12 in. Ready mix concrete was poured into the formwork and 3 concrete cubes were cast with the tags embedded within them. Readers that could be connected to a laptop were used to monitor and collect the time at which these RFID tags can be detected.
The test showed that the RFID signals from the low
frequency tags at all depths were detected as soon as concrete was poured. The Ultra
High Frequency tags placed at the 4" level could be detected 15 minutes after concrete was poured. The UHF tags at the 8" level could be detected after 30 minutes. The UHF tags at the 12" level took on an average 2 hours to be detected from the vicinity of the formwork. The greater the depth at which the ultra
high frequency tag was buried the longer it took for it to be detected. The
high frequency tags could be detected only at the 4" level. The reason the performance of the HF card degraded in concrete could be because it uses an aluminum foil antenna which is more susceptible to the environment changing the relative permeability. A copper wire antenna could have fared better in this condition, increasing the chances of detecting the tag. Moreover a passive tag was used. The read range and chances of detection could have been increased had an active tag been used. The power of the reader that was used was also very less which might have contributed to the tag not being detected.
Among the tags that were used in the experiment it was found that low
frequency tags was the tag that could be detected the earliest after concrete was poured into the…
Advisors/Committee Members: Kang, Julian (advisor), Mutis, Ivan (committee member), Choi, Gwan (committee member).
Subjects/Keywords: LF Low frequency; HF High frequency; UHF Ultra High frequency; RFID Radio Frequency Identification; Concrete maturity
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APA (6th Edition):
Sridharan, R. (2011). Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-8025
Chicago Manual of Style (16th Edition):
Sridharan, Rajasekaran. “Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete.” 2011. Masters Thesis, Texas A&M University. Accessed March 06, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-8025.
MLA Handbook (7th Edition):
Sridharan, Rajasekaran. “Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete.” 2011. Web. 06 Mar 2021.
Vancouver:
Sridharan R. Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete. [Internet] [Masters thesis]. Texas A&M University; 2011. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-8025.
Council of Science Editors:
Sridharan R. Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete. [Masters Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-8025
10.
Sabri, Kaitlyn A.
Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners.
Degree: 2015, James Madison University
URL: https://commons.lib.jmu.edu/diss201019/22
► The most common type and configuration of hearing loss seen in clinics is high frequency sensorineural hearing loss. High-frequency hearing losses can lead to difficulties…
(more)
▼ The most common type and configuration of hearing loss seen in clinics is
high frequency sensorineural hearing loss.
High-
frequency hearing losses can lead to difficulties understanding speech in noise. Traditional amplification can aid in audibility of
high-
frequency information; however, its success is limited due to acoustic feedback, output limitations of the hearing aids, and loudness discomfort (Bohnert, Nyffeler, & Keilmann, 2010, Turner & Cummings, 1999). Cochlear dead regions further hinder the success of traditional hearing aids, as speech recognition may not improve with increased audibility (Turner & Cummings, 1999).
Frequency-lowering algorithms, developed by four major hearing aid manufacturers, attempt to provide improved audibility and speech understanding. Several studies have assessed the success of this technology; however mixed results have been found. The current study’s purpose is to examine the effects of adaptive
frequency lowering on phoneme identification and sound quality of music. Seven subjects with
high frequency hearing loss were fit with Starkey Xino RITE hearing aids and were tested in two conditions (adaptive
frequency lowering on and adaptive
frequency lowering off). The Nonsense Syllable Test, Speech Perception In Noise test, and sound quality of music forced choice protocol were used to compare the two algorithms. The results of this study revealed no significant differences between traditional amplification and adaptive
frequency lowering algorithm for identification of nonsense syllables, speech perception in noise, and preference of sound quality of music.
Advisors/Committee Members: Ayasakanta Rout.
Subjects/Keywords: hearing aids; high frequency hearing loss; frequency lowering; adaptive frequency lowering; Speech Pathology and Audiology
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APA (6th Edition):
Sabri, K. A. (2015). Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners. (Doctoral Dissertation). James Madison University. Retrieved from https://commons.lib.jmu.edu/diss201019/22
Chicago Manual of Style (16th Edition):
Sabri, Kaitlyn A. “Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners.” 2015. Doctoral Dissertation, James Madison University. Accessed March 06, 2021.
https://commons.lib.jmu.edu/diss201019/22.
MLA Handbook (7th Edition):
Sabri, Kaitlyn A. “Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners.” 2015. Web. 06 Mar 2021.
Vancouver:
Sabri KA. Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners. [Internet] [Doctoral dissertation]. James Madison University; 2015. [cited 2021 Mar 06].
Available from: https://commons.lib.jmu.edu/diss201019/22.
Council of Science Editors:
Sabri KA. Effect of adaptive frequency lowering on phoneme identification and sound quality of music in hearing-impaired listeners. [Doctoral Dissertation]. James Madison University; 2015. Available from: https://commons.lib.jmu.edu/diss201019/22
NSYSU
11.
Sie, Wun-Ge.
Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials.
Degree: Master, Electro-Optical Engineering, 2009, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0720109-191858
► In this research, we used monomer 4,4ââââ-Difluore-3,3ââââ- bis(trifluoromethyl)-2ââ,3ââ,5ââ,6ââ-triphenyl and 4,4'-(9-Fluorenylidene) diphenol to fabricate the novel poly(arylene ether)s by the nucleophilic replacement reaction. We call this…
(more)
▼ In this research, we used monomer 4,4ââââ-Difluore-3,3ââââ- bis(trifluoromethyl)-2ââ,3ââ,5ââ,6ââ-triphenyl and 4,4'-(9-Fluorenylidene) diphenol to fabricate the novel poly(arylene ether)s by the nucleophilic replacement reaction. We call this polymers P-44, and we use Mass and GPC to measure its molecular weightï¼The molecular structures were investigated and confirmed by NMR and FT-IR. This polymer has
high weightaverage molecular weight (Mw) about 5.67Ã104 g/mol.
We can realize from the measurement of thermal analysis that its thermal degradation temperature (Td) is 543°C, and its glass transition temperature (Tg) is 331°C. It shows this polymer: P-44 possesses great thermal stability. Besides, P-44 has not apparent crystallizing point (Tc) so we can adjust that P-44 crystalize hardly. We can know from above that P-44 can not only has good heat tolerance but also has
high thermal stability so it can endure futher
high tempaerature in the process of fabrication. After interpreting P-44 possesses these well properties, we want to know the properties that P-44 apply to the devices as flexible substrate. So, we fabricate P-44 to be film, and we measure the photoelectrical properties of P-44 film. From this we can observer if P-44 can match the necessary condition that it apply to monitor or
high frequency substrate.
In the aspect of photophysical properties, we take the 0.3mm P-44 film to measure its photophysical properties. We obtained absorption wavelength that is 245nm and 345nm, and its excitation wavelength is362nmå365nm. Its main area of absorption and excitation is in the region of UV. Furthermore, the transmission spectra of P-44 film showed that visible light transparency were up to 80%. And the refractive index(n) of P-44 film is between 1.37~1.4.
In the aspect of thermal mechanical properties, we can know thermal expansion coefficient (CTE) of P-44 film is 19ppm/â, and we can also obtain the heat deflection temperature (HDT) of P-44 film is 316â. It reveals P-44 possesses low thermal expansion coefficient (CTE) and
high heat deflection temperature (HDT).
In the aspect of surface, we find P-44 film has low polarity whose main component is van der waals and it has good hydrophobicity.Its contact angle with DI-water is 114.5° which greater than 90° that proves P-44 film has well hydrophobicity.
In the aspect of dielectrical properties, we found that its dielectric constant is between 2.51~2.53 under the condition of1M Hz, and its dielectric loss is between 0.0068~0.0071. It shows P-44 film possesses low dielectric constant that let the effect of parasitic capacitances loweredï¼and low dielectric loss let the loss of signal reduced.
We can plate ITO onto P-44 film successfully, and it could be a flexible transparent conductive film.
By the all of the above results, we can realize P-44 film possesses well thermal stabilitiesã
high transparency in the region of visible lightãgood hydrophobicityãlow thermal expansion coefficient (CTE)ãlow dielectric constant and low dielectric loss. With these great materialIX…
Advisors/Committee Members: Hsin-Lung Chen (chair), Wen-Yao Huang (committee member), Mei-Ying Chang (chair), Yu-Kai Han (chair), Ping-Tsung Huang (chair).
Subjects/Keywords: Polymer; Flexible substrate; High frequency substrate
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APA (6th Edition):
Sie, W. (2009). Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0720109-191858
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sie, Wun-Ge. “Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials.” 2009. Thesis, NSYSU. Accessed March 06, 2021.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0720109-191858.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sie, Wun-Ge. “Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials.” 2009. Web. 06 Mar 2021.
Vancouver:
Sie W. Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials. [Internet] [Thesis]. NSYSU; 2009. [cited 2021 Mar 06].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0720109-191858.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sie W. Preparation, Study and Application of Electro-Optical Properties of Functional Flexible Substrate Materials. [Thesis]. NSYSU; 2009. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0720109-191858
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
NSYSU
12.
Wu, Chao-Ching.
High Frequency Parameter Estimation of PMSM and Its Applications.
Degree: Master, Electrical Engineering, 2015, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706115-132726
► This thesis utilizes the high-frequency current injection method and the PI-MRI control topology to estimate the electrical parameters of the permanent magnetic synchronous motor (PMSM).…
(more)
▼ This thesis utilizes the
high-
frequency current injection method and the PI-MRI control topology to estimate the electrical parameters of the permanent magnetic synchronous motor (PMSM). Through the motor parameter estimations under various operating conditions, three methods and possible applications concerning PMSM drive and control are developed. 1) Magnetic polarity detection method: The accurate detection of the magnetic polarity combined with the conventional rotor position estimation method enables the start-up of the sensorless PMSM at standstill. 2) Core-loss resistance estimation method: The identification of the
frequency-dependent core-loss resistance helps develop a loss minimization control algorithm for PMSM. 3) On-line tuning of
high-
frequency-injection estimator of the rotor position of the PMSM : On-line estimations of the electrical parameters of the PMSM enable the tuning of the estimator for better performance.
Advisors/Committee Members: Yao-Ching Hsieh (chair), Hau Chen Yen (chair), Shiang-Hwua Yu (committee member), Cheng-Tsung Liu (chair).
Subjects/Keywords: High-frequency current; motor parameter estimation; sensorless
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Manager
APA (6th Edition):
Wu, C. (2015). High Frequency Parameter Estimation of PMSM and Its Applications. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706115-132726
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wu, Chao-Ching. “High Frequency Parameter Estimation of PMSM and Its Applications.” 2015. Thesis, NSYSU. Accessed March 06, 2021.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706115-132726.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wu, Chao-Ching. “High Frequency Parameter Estimation of PMSM and Its Applications.” 2015. Web. 06 Mar 2021.
Vancouver:
Wu C. High Frequency Parameter Estimation of PMSM and Its Applications. [Internet] [Thesis]. NSYSU; 2015. [cited 2021 Mar 06].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706115-132726.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wu C. High Frequency Parameter Estimation of PMSM and Its Applications. [Thesis]. NSYSU; 2015. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706115-132726
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of California – Irvine
13.
Molainezhad, Fatemehe.
Analysis and Design of High-Speed CMOS Frequency Dividers.
Degree: Electrical and Computer Engineering, 2015, University of California – Irvine
URL: http://www.escholarship.org/uc/item/9q86n8b2
► A frequency divider is one of the most fundamental and challenging blocks used in high-speed communication systems. Three high-speed dividers with different topologies, LC-tank frequency…
(more)
▼ A frequency divider is one of the most fundamental and challenging blocks used in high-speed communication systems. Three high-speed dividers with different topologies, LC-tank frequency divider, CML ring frequency divider, and CML DFF frequency divider with negative feedback, are analyzed based on the locking phenomena. The locking to the injected signal happens as long as the frequency and the amplitude of the injected signal are in the desired operation region of the divider's sensitivity curve. A phase shift (which is a function of both frequency and the amplitude of the injected signal) occurs in the circuit and the divider will be locked to the injected frequency.Locking to an external signal may not necessarily occur just by considering the frequency of the injection signal being in the locking range, even if the frequency of the injection signal is very close to the self-oscillation frequency in a wide locking range scenario without the proper injected signal amplitude. To measure the phase shift when the oscillator is locked to the injected frequency, a novel procedure is developed. This procedure gives us a very precise tool to measure the locking phase, instantaneous phase, or the phase between any two signals inside the topology loop and provides a good ability for better understanding of the injection locking concept and the behavior of the divider in the presence of an injected signal. The simulations are using transistor models from TSMC 65nm CMOS process.
Subjects/Keywords: Electrical engineering; CMOS; Frequency Dividers; High-Speed
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Manager
APA (6th Edition):
Molainezhad, F. (2015). Analysis and Design of High-Speed CMOS Frequency Dividers. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/9q86n8b2
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Molainezhad, Fatemehe. “Analysis and Design of High-Speed CMOS Frequency Dividers.” 2015. Thesis, University of California – Irvine. Accessed March 06, 2021.
http://www.escholarship.org/uc/item/9q86n8b2.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Molainezhad, Fatemehe. “Analysis and Design of High-Speed CMOS Frequency Dividers.” 2015. Web. 06 Mar 2021.
Vancouver:
Molainezhad F. Analysis and Design of High-Speed CMOS Frequency Dividers. [Internet] [Thesis]. University of California – Irvine; 2015. [cited 2021 Mar 06].
Available from: http://www.escholarship.org/uc/item/9q86n8b2.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Molainezhad F. Analysis and Design of High-Speed CMOS Frequency Dividers. [Thesis]. University of California – Irvine; 2015. Available from: http://www.escholarship.org/uc/item/9q86n8b2
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Rochester
14.
Nie, Yihua.
Volatility, news, and market impact : a study of HFT
trading behavior.
Degree: PhD, 2019, University of Rochester
URL: http://hdl.handle.net/1802/35411
► I examine how high-frequency traders (HFTs) adjust their trading behavior based on market conditions, as well as their consequent market impact. I represent HFTs' trading…
(more)
▼ I examine how high-frequency traders (HFTs) adjust
their trading behavior based on market conditions, as well as their
consequent market impact. I represent HFTs' trading behavior into
two main categories of trading styles: market-making, whereby HFTs
perform as "liquidity providers" in the Kyle (1985) model, and
active-trading, whereby HFTs actively perform as "informed traders"
in the Kyle framework. Analyzing HFTs' trading styles led to four
novel findings. First, HFTs' market-making activities are
negatively affected by both expected and unexpected stock
volatility components. Second, during news events, HFTs select
their trading styles across different news topics, based on the
informativeness level of each topic. Third, due to the immediate
active-trading strategies upon news events, HFTs facilitate price
discovery only within around 100 seconds after news events. Lastly,
the SEC's short-sale ban act in 2008 effectively restricted HFTs'
active trading styles, but also excluded HFTs from improving the
market price efficiency. Above all, understanding HFTs' market
impact from their trading behavior, rather than mere trading speed,
is essential to fully understanding their roles in the modern
equities markets.
Subjects/Keywords: High-frequency trading; Market microstructure; News; Volatility
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APA ·
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MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nie, Y. (2019). Volatility, news, and market impact : a study of HFT
trading behavior. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/35411
Chicago Manual of Style (16th Edition):
Nie, Yihua. “Volatility, news, and market impact : a study of HFT
trading behavior.” 2019. Doctoral Dissertation, University of Rochester. Accessed March 06, 2021.
http://hdl.handle.net/1802/35411.
MLA Handbook (7th Edition):
Nie, Yihua. “Volatility, news, and market impact : a study of HFT
trading behavior.” 2019. Web. 06 Mar 2021.
Vancouver:
Nie Y. Volatility, news, and market impact : a study of HFT
trading behavior. [Internet] [Doctoral dissertation]. University of Rochester; 2019. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1802/35411.
Council of Science Editors:
Nie Y. Volatility, news, and market impact : a study of HFT
trading behavior. [Doctoral Dissertation]. University of Rochester; 2019. Available from: http://hdl.handle.net/1802/35411
Tampere University
15.
Solomitckii, Dmitrii.
Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
.
Degree: 2019, Tampere University
URL: https://trepo.tuni.fi/handle/10024/118389
► Technological progress leads to the emergence of new concepts, which can change people’s everyday lives and accelerate the transformation of many industries. Among the more…
(more)
▼ Technological progress leads to the emergence of new concepts, which can change people’s everyday lives and accelerate the transformation of many industries. Among the more recent of these revolutionary concepts are big data analysis, artificial intelligence, augmented/virtual reality, quantum computing, and autonomous vehicles. However, this list would be incomplete without referring to fifth-generation (5G) technology, which is driven by several trends. First, the exponential growth of the worldwide monthly smartphone traffic up to 50 petabytes during the next three years will require the development of mobile networks supporting high datasharing capabilities, excellent spectral efficiency, and gigabits per second of throughput. Another trend is Industry 4.0/5.0 (also called the smart factory), which refers to advanced levels of automation requiring millions of distributed sensors/devices connected into a scalable and smart network. Finally, the automation of critical industrial processes, as well as communication between autonomous vehicles, will require 99.999% reliability and under 1 ms latency as they also become the drivers for the emergence of 5G.
Besides traditional sub-6 GHz microwave spectrum, the 5G communication encompasses the novel millimeter-wave bands to mitigate spectrum scarcity and provide large bandwidth of up to several GHz. However, there are challenges to be overcome with the millimeter-wave band. The band suffers from higher pathloss, more atmospheric attenuation, and higher diffraction losses than microwave signals. Because the millimeter-wave band has such a small wavelength (< 1 cm), it is now feasible to implement compact antenna arrays. This enables the use of beamforming and multi-input and multi-output techniques. In this thesis, advanced ray tracing methodology is developed and utilized to simulate the propagation mechanisms and their effect on the system-level metrics. The main novelty of this work is in the introduction of typical millimeter-wave 5G technologies into channel modelling and propagation specifics into the system-level simulation, as well as the adaptation of the ray tracing methods to support extensive simulations with multiple antennas.
Subjects/Keywords: ray tracing
;
5G
;
electromagnetics
;
high-frequency analysis
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APA (6th Edition):
Solomitckii, D. (2019). Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
. (Doctoral Dissertation). Tampere University. Retrieved from https://trepo.tuni.fi/handle/10024/118389
Chicago Manual of Style (16th Edition):
Solomitckii, Dmitrii. “Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
.” 2019. Doctoral Dissertation, Tampere University. Accessed March 06, 2021.
https://trepo.tuni.fi/handle/10024/118389.
MLA Handbook (7th Edition):
Solomitckii, Dmitrii. “Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
.” 2019. Web. 06 Mar 2021.
Vancouver:
Solomitckii D. Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
. [Internet] [Doctoral dissertation]. Tampere University; 2019. [cited 2021 Mar 06].
Available from: https://trepo.tuni.fi/handle/10024/118389.
Council of Science Editors:
Solomitckii D. Evaluation of mmWave 5G Performance by Advanced Ray Tracing Techniques
. [Doctoral Dissertation]. Tampere University; 2019. Available from: https://trepo.tuni.fi/handle/10024/118389
University of Alberta
16.
Lu,huihong.
Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy.
Degree: MS, Department of Electrical and Computer
Engineering, 2012, University of Alberta
URL: https://era.library.ualberta.ca/files/wh246t10x
► Researchers have been using single-element transducers for photoacoustic microscopy (PAM), but such systems have limited depth-of-field due to single focus. This project was to develop…
(more)
▼ Researchers have been using single-element transducers
for photoacoustic microscopy (PAM), but such systems have limited
depth-of-field due to single focus. This project was to develop a
high-frequency annular array transducer for improved depth-of-field
PAM. We have designed a concave 40 MHz ultrasound transducer which
has 8 annular array elements with equal area. The outer ring is 12
mm in diameter, the geometric focus is 12 mm, and the space between
each annulus is 100 µm. The array was fabricated by
lithographically patterning metalized polyimide film to define back
electrodes. 9-micron-PVDF film was press-fit into the array pattern
with epoxy as a backing material and a single drop of epoxy as a
bonding layer. The array exhibits high sensitivity to
high-frequency photoacoustic signals. Dynamic focusing of amplified
and digitized signals permit extended depth-of-field imaging
compared to the single-element transducer case. Dark-field
light-delivery and 3-axis motorized scanning permit 3-D
photoacoustic microscopy.
Subjects/Keywords: high-frequency; annular-array; ultrasound-transducer
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lu,huihong. (2012). Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/wh246t10x
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
Lu,huihong. “Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy.” 2012. Masters Thesis, University of Alberta. Accessed March 06, 2021.
https://era.library.ualberta.ca/files/wh246t10x.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
Lu,huihong. “Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy.” 2012. Web. 06 Mar 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
Lu,huihong. Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy. [Internet] [Masters thesis]. University of Alberta; 2012. [cited 2021 Mar 06].
Available from: https://era.library.ualberta.ca/files/wh246t10x.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
Lu,huihong. Design, Fabrication, and Testing of High-Frequency
High-Numerical-Aperture Annular Array Transducer for Improved
Depth-of-Field Photoacoustic Microscopy. [Masters Thesis]. University of Alberta; 2012. Available from: https://era.library.ualberta.ca/files/wh246t10x
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Pontifícia Universidade Católica de São Paulo
17.
Leila Quadrado Lopes.
Estudo dos limiares auditivos em altas freqüências em adultos.
Degree: 2005, Pontifícia Universidade Católica de São Paulo
URL: http://www.sapientia.pucsp.br//tde_busca/arquivo.php?codArquivo=5376
► O presente estudo teve por objetivo aplicar a audiometria de altas freqüências (9000 a 20000 Hz) visando verificar se lado da orelha faixa etária e…
(more)
▼ O presente estudo teve por objetivo aplicar a audiometria de altas freqüências (9000 a 20000 Hz) visando verificar se lado da orelha faixa etária e sexo são fonte de variabilidade Método Foram selecionados 65 indivíduos (130 orelhas) 22 do sexo masculino e 43 do sexo feminino com idades entre os 20 e 60 anos sem passado otológico, com curvas timpanométricas e limiares de audibilidade na faixa de frequencia convencional (250 a 8000 Hz) dentro da normalidade e presença de reflexos acústicos Foi utilizado na pesquisa das altas freqüencias o audiometro Grason Stadler - GSI 61 e fones Senheiser HDA -200 que possibilitaram a verificação dos limiares auditivos em dB NA Resultados Após análise estatística os resultados demostraram que não houve diferenças estatisticamente significantes com relação ao lado da orelha testada Houve diferenças estatisticamente significantes com relação à faixa etária, sendo piores os limiares auditivos conforme o aumento da idade bem como houve diferencas estatisticamente significantes com relacao à faixa etária sendo piores os limiares auditivos conforme o aumento da idade bem como houve diferencas estatisticamente significantes nos limiares auditivos dos indivíduos dos sexos feminino e masculino sendo que mulheres apresentaram limiares auditivos piores do que homens somente nas frequencias de 16000 e 18000 Hz Entretanto nas demais freqüencias houve uma tendencia à melhora nos limiares para os sujeitos do sexo feminino Conclusao Apesar deste procedimento ainda não ser utilizado na rotina clínica atraves da avaliação das altas freqüências poderemos obter mais informacoes a respeito do sistema auditivo, aumentando assim a compreensão deste e também possibilitando maiores chances de chegarmos a um prognóstico mais preciso sobre as lesões auditivas
The present study aimed at applying high frequency audiometry in the frequency range from 9.000 to 20.000 Hz in individuals, in order to verify if ear, gender and age are variability sources. Method: There were selected 65 individuals (130 ears), being 22 male and 43 female in the age ranging from 20 to 60 years old, with no otological past, with normal tympanometric curves and hearing thresholds in pure tone conventional audiometry (250 8.000 Hz) and presence of acoustic reflexes. The audiometer used was a Grason Stadler GSI 61 with the Senheiser HAD-200 earphones, which allowed dB hearing threshold level. Results: there were no statistically significant differences between tested ears; there were statistically significant differences between age range, being worse the hearing thresholds with the increasing age, as well as there were statistically significant differences between hearing thresholds of female and male individuals, in which women has presented worse hearing thresholds only in 16.000 and 18.000 Hz. Nevertheless, in the other frequencies, there was a tendency of improving the hearing thresholds for female individuals. Conclusion: Despite of this procedure has not being used in the clinical routine, by evaluating the high frequencies…
Advisors/Committee Members: Ieda Chaves Pacheco Russo.
Subjects/Keywords: FONOAUDIOLOGIA; Altas freqüências; Audiometria; Audição; High frequency
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APA ·
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APA (6th Edition):
Lopes, L. Q. (2005). Estudo dos limiares auditivos em altas freqüências em adultos. (Thesis). Pontifícia Universidade Católica de São Paulo. Retrieved from http://www.sapientia.pucsp.br//tde_busca/arquivo.php?codArquivo=5376
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lopes, Leila Quadrado. “Estudo dos limiares auditivos em altas freqüências em adultos.” 2005. Thesis, Pontifícia Universidade Católica de São Paulo. Accessed March 06, 2021.
http://www.sapientia.pucsp.br//tde_busca/arquivo.php?codArquivo=5376.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lopes, Leila Quadrado. “Estudo dos limiares auditivos em altas freqüências em adultos.” 2005. Web. 06 Mar 2021.
Vancouver:
Lopes LQ. Estudo dos limiares auditivos em altas freqüências em adultos. [Internet] [Thesis]. Pontifícia Universidade Católica de São Paulo; 2005. [cited 2021 Mar 06].
Available from: http://www.sapientia.pucsp.br//tde_busca/arquivo.php?codArquivo=5376.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lopes LQ. Estudo dos limiares auditivos em altas freqüências em adultos. [Thesis]. Pontifícia Universidade Católica de São Paulo; 2005. Available from: http://www.sapientia.pucsp.br//tde_busca/arquivo.php?codArquivo=5376
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Waterloo
18.
Ling, Yun.
Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology.
Degree: 2019, University of Waterloo
URL: http://hdl.handle.net/10012/15338
► Particle tracking of passive microscopic species has become the experimental measurement of choice in diverse applications, where either the material volumes are limited, or the…
(more)
▼ Particle tracking of passive microscopic species has become the experimental measurement of choice in diverse applications, where either the material volumes are limited, or the materials themselves are so soft that they deform uncontrollably under the stresses and strains of traditional instruments. As such, the results of countless biological and rheological analyses hinge pivotally on extracting reliable dynamical information from large datasets of particle trajectory recordings. However, to do this in a statistically and computationally efficient manner presents a number of important challenges. Addressing some of these challenges is the focus of the present work.
In Chapter 2, we present a superfast set of tools for parametric inference in single-particle tracking. Parametric likelihoods for particle trajectory measurements typically consist of stationary Gaussian time series, for which traditional fast inference algorithms scale as N-square in the number of observations. We present a superfast algorithm for parametric inference for stationary Gaussian processes and propose novel superfast algorithms for score and Hessian calculations. This effectively enables superfast inference for stationary Gaussian process via a wide array of frequentist and Bayesian methods.
In Chapters 3 and 4, we use the superfast toolkit to address two outstanding problems prevalent in many particle tracking analyses. The first is that particle position measurements are generally contaminated by various forms of high-frequency errors. Failure to account for these errors leads to considerable bias in estimation results. In Chapter 3 we propose a novel strategy to filter high-frequency noise from measurements of particle positions. Our filters are shown theoretically to cover a vast range of high-frequency noise regimes and lead to an efficient computational estimator of model coefficients. Analyses of numerous experimental and simulated datasets suggest that our filtering approach performs remarkably well.
The second problem we address is the considerable heterogeneity of typical biological fluids in which particle tracking experiments are conducted. In Chapter 4, we propose a simple metric by which to quantify the degree of heterogeneity of a fluid, along with a computationally efficient estimator and statistical test against the hypothesis that the fluid is homogeneous. The thesis is concluded by outlining several directions for future research.
Subjects/Keywords: Toeplitz matrix; high-frequency camera errors; heterogeneity
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APA ·
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Export
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Manager
APA (6th Edition):
Ling, Y. (2019). Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15338
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ling, Yun. “Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology.” 2019. Thesis, University of Waterloo. Accessed March 06, 2021.
http://hdl.handle.net/10012/15338.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ling, Yun. “Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology.” 2019. Web. 06 Mar 2021.
Vancouver:
Ling Y. Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology. [Internet] [Thesis]. University of Waterloo; 2019. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10012/15338.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ling Y. Superfast Inference for Stationary Gaussian Processes in Particle Tracking Microrheology. [Thesis]. University of Waterloo; 2019. Available from: http://hdl.handle.net/10012/15338
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Queens University
19.
Abnavi, Somayeh.
High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
.
Degree: Electrical and Computer Engineering, Queens University
URL: http://hdl.handle.net/1974/15263
► In modern power electronics equipment, it is desirable to design a low profile, high power density, and fast dynamic response converter. Increases in switching frequency…
(more)
▼ In modern power electronics equipment, it is desirable to design a low profile, high power density, and fast dynamic response converter. Increases in switching frequency reduce the size of the passive components such as transformers, inductors, and capacitors which results in compact size and less requirement for the energy storage. In addition, the fast dynamic response can be achieved by operating at high frequency. However, achieving high frequency operation while keeping the efficiency high, requires new advanced devices, higher performance magnetic components, and new circuit topology. These are required to absorb and utilize the parasitic components and also to mitigate the frequency dependent losses including switching loss, gating loss, and magnetic loss. Required performance improvements can be achieved through the use of Radio Frequency (RF) design techniques.
To reduce switching losses, resonant converter topologies like resonant RF amplifiers (inverters) combined with a rectifier are the effective solution to maintain high efficiency at high switching frequencies through using the techniques such as device parasitic absorption, Zero Voltage Switching (ZVS), Zero Current Switching (ZCS), and a resonant gating. Gallium Nitride (GaN) device technologies are being broadly used in RF amplifiers due to their lower on- resistance and device capacitances compared with silicon (Si) devices. Therefore, this kind of semiconductor is well suited for high frequency power converters.
The major problems involved with high frequency magnetics are skin and proximity effects, increased core and copper losses, unbalanced magnetic flux distribution generating localized hot spots, and reduced coupling coefficient. In order to eliminate the magnetic core losses which play a crucial role at higher operating frequencies, a coreless PCB transformer can be used. Compared to the conventional wire-wound transformer, a planar PCB transformer in which the windings are
laid on the Printed Board Circuit (PCB) has a low profile structure, excellent thermal characteristics, and ease of manufacturing.
Therefore, the work in this thesis demonstrates the design and analysis of an isolated low profile class DE resonant converter operating at 10 MHz switching frequency with a nominal output of 150 W. The power stage consists of a class DE inverter using GaN devices along with a sinusoidal gate drive circuit on the primary side and a class DE rectifier on the secondary side. For obtaining the stringent height converter, isolation is provided by a 10-layered coreless PCB transformer of 1:20 turn’s ratio. It is designed and optimized using 3D Finite Element Method (FEM) tools and radio frequency (RF) circuit design software. Simulation and experimental results are presented for a 10-layered coreless PCB transformer operating in 10 MHz.
Subjects/Keywords: High Frequency Converter
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APA (6th Edition):
Abnavi, S. (n.d.). High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/15263
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Abnavi, Somayeh. “High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
.” Thesis, Queens University. Accessed March 06, 2021.
http://hdl.handle.net/1974/15263.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abnavi, Somayeh. “High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
.” Web. 06 Mar 2021.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Vancouver:
Abnavi S. High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
. [Internet] [Thesis]. Queens University; [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1974/15263.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
Council of Science Editors:
Abnavi S. High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer
. [Thesis]. Queens University; Available from: http://hdl.handle.net/1974/15263
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
University of Ottawa
20.
Alkhammash, Elham.
Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
.
Degree: 2020, University of Ottawa
URL: http://hdl.handle.net/10393/40246
► Studying the synaptic transmission in the neuromuscular junction (NMJ) is central to the understanding of firing electrical signals at high frequencies. In this work, we…
(more)
▼ Studying the synaptic transmission in the neuromuscular junction (NMJ) is central to the understanding of firing electrical signals at high frequencies. In this work, we present the processes involving acetylcholine and its receptors in the synaptic transmission across the cleft.
A one-dimensional diffusion model is proposed to explain the behavior of the reaction -diffusion system with nonlinear reaction terms monitoring the interaction of acetylcholine with the enzyme and the receptors. A proper numerical method is applied to solve the one-dimensional diffusion equation along the symmetry axis of the cylindrically shaped cleft with Neumann boundary condition on the postsynaptic end.
We assumed a periodic release of ACh in the frequency range of 200Hz to 500Hz. The kinetics of receptors (particularly the open receptors) during the release of acetylcholine to changes in selected parameters are investigated. We chose typical values for the concentration of ACh, the flux of ACh, and the surface concentration of receptors. The effects of the varying parameters, enzyme concentration, input flux, and the receptor concentration on the emission of acetylcholine in the synaptic cleft and the subsequent impact on the dynamics of the receptors are studied and discussed.
As the firing rate is increased, the enzyme concentration also has to be increased to ensure that the ACh receptors (AChR) close in between two releases of ACh. Our study revealed that the enzyme reaction limits our model. The concentration of ACh reaching the receptors falls close to a threshold and the receptors do not close completely during firing at a high frequency, such as 500 Hz. Our model can be used to describe the neuronal transmission across the synaptic up to about 500Hz. This being close to the physiological limit of Eigenmannia, it suggests that the mechanism described in this thesis reflects reality.
Subjects/Keywords: High frequency;
Synaptic transmission;
Weakly electric fish
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alkhammash, E. (2020). Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
. (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/40246
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Alkhammash, Elham. “Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
.” 2020. Thesis, University of Ottawa. Accessed March 06, 2021.
http://hdl.handle.net/10393/40246.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Alkhammash, Elham. “Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
.” 2020. Web. 06 Mar 2021.
Vancouver:
Alkhammash E. Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
. [Internet] [Thesis]. University of Ottawa; 2020. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10393/40246.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Alkhammash E. Modeling the Reaction Transport of Synaptic Acetylcholine Released at High Frequency in Weakly Electric Fish
. [Thesis]. University of Ottawa; 2020. Available from: http://hdl.handle.net/10393/40246
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Chicago
21.
Su, Jian.
An Empirical Study of Intra-day Stock Return Volatility.
Degree: 2012, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/9104
► It is well known that microstructure noise could have substantial impact on volatility estimation of high frequency asset returns. The Two Scale Realized Volatility (TSRV)…
(more)
▼ It is well known that microstructure noise could have substantial impact on volatility estimation of
high frequency asset returns. The Two Scale Realized Volatility (TSRV) estimator
makes use of all the available data and at the same time corrects the effect of market microstructure noise. In this study, 30-minute TSRV series is constructed from tick-by-tick Dow Jones 30 stock prices. Our results show that the 30-minute volatility estimate series has the stylized characteristics, including volatility clustering, long memory and displaying U-shape within the day. Also, the volatility for stocks during earning announcement period is significantly higher than that in non-announcement period. This phenomenon is particularly striking at the opening hour of the announcement day. Time series model is built on the periodic and
long memory features with rolling window size of one month. We forecast the out-of-sample
30-minute volatility one day ahead based on Semi-parametric Fractional Autoregressive model and modified HAR-RV linear regression model.
Advisors/Committee Members: Zhang, Lan (advisor), Bassett, Gilbert (committee member), Sclove, Stanley (committee member), Majumdar, Dibyen (committee member), Wang, Fangfang (committee member).
Subjects/Keywords: realized volatility; high frequency; microstructure noise
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APA ·
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Export
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APA (6th Edition):
Su, J. (2012). An Empirical Study of Intra-day Stock Return Volatility. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/9104
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Su, Jian. “An Empirical Study of Intra-day Stock Return Volatility.” 2012. Thesis, University of Illinois – Chicago. Accessed March 06, 2021.
http://hdl.handle.net/10027/9104.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Su, Jian. “An Empirical Study of Intra-day Stock Return Volatility.” 2012. Web. 06 Mar 2021.
Vancouver:
Su J. An Empirical Study of Intra-day Stock Return Volatility. [Internet] [Thesis]. University of Illinois – Chicago; 2012. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10027/9104.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Su J. An Empirical Study of Intra-day Stock Return Volatility. [Thesis]. University of Illinois – Chicago; 2012. Available from: http://hdl.handle.net/10027/9104
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Leicester
22.
Jackson, Clive Andrew.
Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths.
Degree: PhD, 2003, University of Leicester
URL: https://figshare.com/articles/Combined_channel_sounding_and_direction_finding_studies_of_HF_radio_propagation_effects_observed_over_high_latitude_communication_paths/10127792
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275475
► The high latitude ionosphere is a dynamic region that is subject to a variety of disturbed conditions affecting oblique propagation of HF radio signals. Multipath…
(more)
▼ The high latitude ionosphere is a dynamic region that is subject to a variety of disturbed conditions affecting oblique propagation of HF radio signals. Multipath and off great circle propagation resulting from rough ionospheric reflecting surfaces introduce time dispersion, while movements in the ionosphere impose Doppler dispersion. These effects, when combined, result in very complex signal characteristics, which cause degradation to the performance of communication systems if the delay or Doppler dispersion exceeds system dependent bounds.;Results are presented based around measurements of signals, produced by the Doppler And Multipath SOunding Network, recorded using a six channel spaced array receiving system, during a 10 day campaign at Kiruna in March 1998. In addition to delay and Doppler processing, the directions of arrival (DOA) of the signal components were estimated using a super resolution direction finding algorithm.;Most signals were narrow in delay and Doppler, however a significant statistical spread in their DOA was observed. Statistics on the occurrence and characteristics of the remaining signals revealed that trends in DOA are often associated with complex delay and Doppler propagation. A number of cases had Doppler spread exceeding a specified Doppler boundary of operation, while none exceeded the delay spread boundary.;Case studies revealed detailed propagation effects. Of particular interest is the often observed East → West trend in DOA with Doppler offset. This is attributed to scattering from irregularities embedded in turbulent bulk convection flows. E-region modes with good spectral and geographic distribution of signal energy are often observed in otherwise complex cases.;Spatial filtering, using two or three element arrays was investigated and found to be effective at reducing large Doppler spreads to lower values more amenable to high data rate communication systems. Fast solver spatial filtering methods were found to be very robust, effective and a lot quicker.
Subjects/Keywords: 621; High frequency
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APA (6th Edition):
Jackson, C. A. (2003). Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths. (Doctoral Dissertation). University of Leicester. Retrieved from https://figshare.com/articles/Combined_channel_sounding_and_direction_finding_studies_of_HF_radio_propagation_effects_observed_over_high_latitude_communication_paths/10127792 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275475
Chicago Manual of Style (16th Edition):
Jackson, Clive Andrew. “Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths.” 2003. Doctoral Dissertation, University of Leicester. Accessed March 06, 2021.
https://figshare.com/articles/Combined_channel_sounding_and_direction_finding_studies_of_HF_radio_propagation_effects_observed_over_high_latitude_communication_paths/10127792 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275475.
MLA Handbook (7th Edition):
Jackson, Clive Andrew. “Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths.” 2003. Web. 06 Mar 2021.
Vancouver:
Jackson CA. Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths. [Internet] [Doctoral dissertation]. University of Leicester; 2003. [cited 2021 Mar 06].
Available from: https://figshare.com/articles/Combined_channel_sounding_and_direction_finding_studies_of_HF_radio_propagation_effects_observed_over_high_latitude_communication_paths/10127792 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275475.
Council of Science Editors:
Jackson CA. Combined channel sounding and direction finding studies of HF radio propagation effects observed over high latitude communication paths. [Doctoral Dissertation]. University of Leicester; 2003. Available from: https://figshare.com/articles/Combined_channel_sounding_and_direction_finding_studies_of_HF_radio_propagation_effects_observed_over_high_latitude_communication_paths/10127792 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275475
23.
Kiselev, Ilya.
Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index.
Degree: Economics, 2012, Jönköping UniversityJönköping University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19495
► The research at hand aims to define effectiveness of algorithmic trading, comparing with different benchmarks represented by several types of indexes. How big returns…
(more)
▼ The research at hand aims to define effectiveness of algorithmic trading, comparing with different benchmarks represented by several types of indexes. How big returns can be gotten by algorithmic trading, taking into account the costs of informational and trading infrastructure needed for robot trading implementation? To get the result, it’s necessary to compare two opposite trading strategies: 1) Algorithmic trading (implemented by high-frequency trading robot (based on statistic arbitrage strategy) and trend-following trading robot (based on the indicator Exponential Moving Average with the Variable Factor of Smoothing)) 2) Index investing strategy (classical index strategies “buy and hold”, implemented by four different types of indexes: Capitalization weight index, Fundamental indexing, Equal-weighted indexing, Risk-based indexation/minimal variance). According to the results, it was found that at the current phase of markets’ development, it is theoretically possible for algorithmic trading (and especially high-frequency strategies) to exceed the returns of index strategy, but we should note two important factors: 1) Taking into account all of the costs of organization of high-frequency trading (brokerage and stock exchanges commissions, trade-related infrastructure maintenance, etc.), the difference in returns (with superiority of high-frequency strategy) will be much less . 2) Given the fact that “markets’ efficiency” is growing every year (see more about it further in thesis), and the returns of high-frequency strategies tends to decrease with time (see more about it further in thesis), it is quite logical to assume that it will be necessary to invest more and more in trading infrastructure to “fix” the returns of high-frequency trading strategies on a higher level, than the results of index investing strategies.
Subjects/Keywords: Algorithmic trading; high-frequency trading; investment strategy
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APA (6th Edition):
Kiselev, I. (2012). Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index. (Thesis). Jönköping UniversityJönköping University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19495
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kiselev, Ilya. “Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index.” 2012. Thesis, Jönköping UniversityJönköping University. Accessed March 06, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19495.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kiselev, Ilya. “Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index.” 2012. Web. 06 Mar 2021.
Vancouver:
Kiselev I. Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index. [Internet] [Thesis]. Jönköping UniversityJönköping University; 2012. [cited 2021 Mar 06].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19495.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kiselev I. Can algorithmic trading beat the market? : An experiment with S&P 500, FTSE 100, OMX Stockholm 30 Index. [Thesis]. Jönköping UniversityJönköping University; 2012. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19495
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
24.
Arikan, Toros.
Minimum-delay HF communications.
Degree: MS, Electrical & Computer Engr, 2017, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/97507
► HF radio communications offer latency advantages over fiber-optics and are more economical than satellite links in long-distance communication applications. As a result, there is renewed…
(more)
▼ HF radio communications offer latency advantages over fiber-optics and are more economical than satellite links in long-distance communication applications. As a result, there is renewed interest in the field of HF from the
high-
frequency trading industry, as a means of transmitting financial data. Ideally, decisions should be made on received symbols as soon as they arrive, without waiting for other samples to accumulate. A significant problem is that the ionospheric HF channel is a dynamic medium that is considered one of the most challenging communication channels. In this thesis, we investigate alternative techniques towards reliable communication with minimum delay. We study HF channel models and communication link design tools, which indicate that our minimum-delay problem is feasible but difficult to solve. Extant HF modems are observed to add prohibitive amounts of latency to ensure robustness, motivating us to design receivers that provide good performance given a delay constraint. We adapt a coupled MAP-RLS receiver studied in literature to the HF channel to yield minimal decision-making delay. We introduce a multitrellis adaptive Viterbi algorithm (MAVA) that solves the problem of equalization for sparse and time-varying ISI channels, producing a robust MLSE receiver with several milliseconds of decision-making delay. Finally, we cascade this MLSE receiver with MAP detection to obtain
high-fidelity low-delay performance, finding a practical solution to minimum-delay HF communications.
Advisors/Committee Members: Singer, Andrew C (advisor).
Subjects/Keywords: Channel equalization; High frequency (HF) communications
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Arikan, T. (2017). Minimum-delay HF communications. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/97507
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Arikan, Toros. “Minimum-delay HF communications.” 2017. Thesis, University of Illinois – Urbana-Champaign. Accessed March 06, 2021.
http://hdl.handle.net/2142/97507.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Arikan, Toros. “Minimum-delay HF communications.” 2017. Web. 06 Mar 2021.
Vancouver:
Arikan T. Minimum-delay HF communications. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2017. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/2142/97507.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Arikan T. Minimum-delay HF communications. [Thesis]. University of Illinois – Urbana-Champaign; 2017. Available from: http://hdl.handle.net/2142/97507
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Southern California
25.
Zheng, Fan.
High frequency ultrasonic phased array system and its
applications.
Degree: PhD, Biomedical Engineering, 2012, University of Southern California
URL: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/109547/rec/3170
► While similar to a linear-switched array in structure, an ultrasound linear phased array (simply called phased array) is quite different in operation. It is capable…
(more)
▼ While similar to a linear-switched array in structure,
an ultrasound linear phased array (simply called phased array) is
quite different in operation. It is capable of beam steering to
form fan-shaped sector images without inducing grating lobes.
Moreover, the relative smaller array footprint is useful where only
very limited contact surface is permitted.
High frequency phased
arrays combine the advantages of the phased array and
high
frequency ultrasound, which offer both small footprint and
high
spatial resolution. This dissertation reports the design and
development of a digital ultrasonic imaging platform with raw RF
data acquisition capability, which can be paired with a prototype
64-element 26 MHz phased array transducer. A wire phantom image
showed that -6 dB lateral and axial resolutions were 209 and 104
μm, respectively, which were in good agreement with the Field II
simulation. Anechoic cyst tissue-mimicking phantom images
demonstrated its capability to detect cysts of 300 μm in diameter.
An image of a rabbit eyeball in vitro was also acquired. This
imaging platform is designed for the purpose of testing
high
frequency phased arrays under development as well as facilitating
the development in novel array signal processing algorithms. ❧
Without additional change in the system hardware, the current
high
frequency array system can be also applied in the industrial
non-destructive testing (NDT) applications. A motorized XY stage
allows the array system to acquire C-mode scan as well as normal
B-mode scan with bigger scanning area. Electronic scanning in array
system could dramatically reduce the total scanning time compare to
single element system. An aluminum sample and a silicon carbide
sample were examined to test the system in non-destructive testing.
❧ Besides the applications in biomedical imaging and
non-destructive testing, the
high frequency ultrasonic phased array
and system are shown to be capable of trapping and translating
microparticles precisely and efficiently, made possible due to the
fact that the acoustic beam produced by a phased array can be both
focused and steered. Acoustic manipulation of microparticles by a
phased array is advantageous over a single element transducer since
there is no mechanical movement required for the array.
Experimental results show that 45 μm diameter polystyrene
microspheres can be easily and accurately trapped and moved to
desired positions by a 64-element 26 MHz phased
array.
Advisors/Committee Members: Shung, Kirk Koping (Committee Chair), Yen, Jesse T. (Committee Member), Kim, Eun Sok (Committee Member), Zhou, Qifa (Committee Member).
Subjects/Keywords: high frequency; ultrasound; phased array; imaging system
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zheng, F. (2012). High frequency ultrasonic phased array system and its
applications. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/109547/rec/3170
Chicago Manual of Style (16th Edition):
Zheng, Fan. “High frequency ultrasonic phased array system and its
applications.” 2012. Doctoral Dissertation, University of Southern California. Accessed March 06, 2021.
http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/109547/rec/3170.
MLA Handbook (7th Edition):
Zheng, Fan. “High frequency ultrasonic phased array system and its
applications.” 2012. Web. 06 Mar 2021.
Vancouver:
Zheng F. High frequency ultrasonic phased array system and its
applications. [Internet] [Doctoral dissertation]. University of Southern California; 2012. [cited 2021 Mar 06].
Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/109547/rec/3170.
Council of Science Editors:
Zheng F. High frequency ultrasonic phased array system and its
applications. [Doctoral Dissertation]. University of Southern California; 2012. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll3/id/109547/rec/3170
University of Southern California
26.
Park, Jinhyoung.
High frequency chirp coded excitation ultrasound imaging
system.
Degree: PhD, Biomedical Engineering, 2011, University of Southern California
URL: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/664082/rec/3169
► An increase of imaging frequency enhances the performance in spatial resolution of an ultrasound scanner while sacrificing echo signal to noise ratio (eSNR) because of…
(more)
▼ An increase of imaging
frequency enhances the
performance in spatial resolution of an ultrasound scanner while
sacrificing echo signal to noise ratio (eSNR) because of a rise in
the amount of attenuation. As solutions to raise the eSNR level
while maintaining the enhanced spatial resolution, both fundamental
and harmonic coded excitation imaging methods have been proposed.
For this purpose, ultrasound bio-microscopes (UBM) capable of chirp
coded excitations were implemented on both a linear and a sector
mechanical scanning system. A custom-designed broadband (5 MHz –
140 MHz) linear power amplifier was designed as a part of a low
noise arbitrary pulse generator to replace a commercial bench-top
power amplifier in the linear UBM. The modified imaging system
exhibited a better eSNR of 7 dB than the system with a commercial
power amplifier while maintaining the spatial resolution in a wire
target measurement. In-vivo imaging was carried on pig eye and
zebrafish embryo using a 40 MHz and a 100 MHz single element
transducer respectively. For
high frame rate coded excitation
imaging, a standalone frontend system for a sector UBM was
implemented. The custom-designed system consisting of a
transmitter, a receiver, a motor controller and a motor position
interpreter achieved an eSNR of 66 dB utilizing chirp coded
excitation for wire target imaging. Moreover, contrast to noise
ratio (CNR) was improved from 2.92 to 3.18 with coded excitation.
This modified scanner allowed contraction of cardiac chambers of
both zebrafish and mouse hearts to be clearly visualized. As an
effort to enhance the spatial resolution, pulse inversion chirp
coded tissue harmonic imaging (PI-CTHI) was programmed into the
custom-designed frontend system. In a wire target study using a 40
MHz single element transducer, lateral resolution was found to be
110 μm, which was narrower than fundamental imaging at153 μm. CNR
was found to improve by 34 % when chirp coded excitation was
applied to harmonic imaging. This imaging mode was shown to better
delineate the clot formation in adult zebrafish heart imaging when
the heart was amputated and allowed to regenerate.
Advisors/Committee Members: Yen, Jesse T.Hsiai, Tzung K.Kuo, C.-C. JayShung, K. Kirk (Committee Chair).
Subjects/Keywords: high frequency ultrasound imaging; chirp coded excitation
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Park, J. (2011). High frequency chirp coded excitation ultrasound imaging
system. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/664082/rec/3169
Chicago Manual of Style (16th Edition):
Park, Jinhyoung. “High frequency chirp coded excitation ultrasound imaging
system.” 2011. Doctoral Dissertation, University of Southern California. Accessed March 06, 2021.
http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/664082/rec/3169.
MLA Handbook (7th Edition):
Park, Jinhyoung. “High frequency chirp coded excitation ultrasound imaging
system.” 2011. Web. 06 Mar 2021.
Vancouver:
Park J. High frequency chirp coded excitation ultrasound imaging
system. [Internet] [Doctoral dissertation]. University of Southern California; 2011. [cited 2021 Mar 06].
Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/664082/rec/3169.
Council of Science Editors:
Park J. High frequency chirp coded excitation ultrasound imaging
system. [Doctoral Dissertation]. University of Southern California; 2011. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/664082/rec/3169
University of Hawaii – Manoa
27.
Cass, Jacob.
High frequency radio observations of tides and currents south of O'ahu.
Degree: 2016, University of Hawaii – Manoa
URL: http://hdl.handle.net/10125/101652
► M.S. University of Hawaii at Manoa 2010.
A year of radial current data from a high frequency radio current meter (HFR) on Oahu's south shore…
(more)
▼ M.S. University of Hawaii at Manoa 2010.
A year of radial current data from a high frequency radio current meter (HFR) on Oahu's south shore is analyzed from long to short time scales. Monthly and seasonal currents reveal a large scale inversion in the winter months of the typically westward propagating flow. A region of significant cyclonic flow west of Penguin Bank is identified as an eddy generation zone likely driven by cyclonic wind stress curl. Island trapped waves are investigated while complications from local vorticity and the close proximity of the inertial period are considered. Observed tidal characteristics are compared with three existing models. Incoherent tidal features, presumably attributed to energetic internal tides in the area, are presented. Deep-ocean Assessment and Reporting of Tsunamis (DART) buoy data is used to determine the open ocean characteristics of waves generated by the Samoan and Chilean tsunamis and predict the surfaces currents excited as they approached Oahu. An complex-demodulation based on the tsunami's dominant period is conducted to amplify any evidence for the tsunamis in the record because the predicted currents were below the detection threshold of the HFR.
Subjects/Keywords: high frequency radio current meter; oceanography
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cass, J. (2016). High frequency radio observations of tides and currents south of O'ahu. (Thesis). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/101652
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cass, Jacob. “High frequency radio observations of tides and currents south of O'ahu.” 2016. Thesis, University of Hawaii – Manoa. Accessed March 06, 2021.
http://hdl.handle.net/10125/101652.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cass, Jacob. “High frequency radio observations of tides and currents south of O'ahu.” 2016. Web. 06 Mar 2021.
Vancouver:
Cass J. High frequency radio observations of tides and currents south of O'ahu. [Internet] [Thesis]. University of Hawaii – Manoa; 2016. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10125/101652.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cass J. High frequency radio observations of tides and currents south of O'ahu. [Thesis]. University of Hawaii – Manoa; 2016. Available from: http://hdl.handle.net/10125/101652
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Waterloo
28.
Wisebourt, Shaul Sergey.
Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information.
Degree: 2011, University of Waterloo
URL: http://hdl.handle.net/10012/5921
► Over the last fifty years financial markets have seen an enormous expansion and development both in size and variety. An industry that was once small…
(more)
▼ Over the last fifty years financial markets have seen an enormous expansion and development both in size and variety. An industry that was once small and secluded has transformed into an essential part of today’s economy. Such changes should in part be attributed to substantial advances in computer technology. The latest allowed for a transition from face-to-face trading on organized exchanges to a distributed system of electronic markets with new mechanisms serving the purposes of efficiency, transparency and liquidity. In majority of cases this new trading system is driven by a double auction market mechanism, in which market participants submit buy and sell orders, aiming to strike a balance between certainty of execution and attractiveness of trade price. Generally, information about outstanding buy and sell orders is made available to market participants in the form of a limit order book. It has been suggested by multiple prior research that limit order books contain information that could be used to derive market sentiment and predict future price movement.
In the current study we have presented ideas behind double auction market mechanism and have attempted to model run and reversal market regimes using a simple and intuitive Hierarchical Hidden Markov Model. We have proposed a statistical measure of the limit order book imbalance and have used it to build observation (feature) vector for our model. We have built Limit Order Book analyzer – the software tool that has become essential for data cleaning and validation, as well as extraction of feature vector components from the data. We have used the model on high frequency tick-by-tick trade and limit order book data from the Toronto Stock Exchange. We have performed the analysis of computational results; for this purpose we have used a sample of annualized returns of stocks which comprised the TSX60 index at the time of data collection; we have performed the comparative analysis of our results with a simple daily buy & hold trading strategy as well as results of the trade price and volume model presented in the prior research.
Subjects/Keywords: Markov; Model; High; Frequency; Market; Regimes
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APA ·
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MLA ·
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wisebourt, S. S. (2011). Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/5921
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wisebourt, Shaul Sergey. “Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information.” 2011. Thesis, University of Waterloo. Accessed March 06, 2021.
http://hdl.handle.net/10012/5921.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wisebourt, Shaul Sergey. “Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information.” 2011. Web. 06 Mar 2021.
Vancouver:
Wisebourt SS. Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information. [Internet] [Thesis]. University of Waterloo; 2011. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/10012/5921.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wisebourt SS. Hierarchical Hidden Markov Model of High-Frequency Market Regimes using Trade Price and Limit Order Book Information. [Thesis]. University of Waterloo; 2011. Available from: http://hdl.handle.net/10012/5921
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Kansas State University
29.
Zhang, Zhihan.
Selected
results from clustering and analyzing stock market trade
data.
Degree: MS, Department of
Statistics, 2018, Kansas State University
URL: http://hdl.handle.net/2097/39297
► The amount of data generated from stock market trading is massive. For example, roughly 10 million trades are performed each day on the NASDAQ stock…
(more)
▼ The amount of data generated from stock market trading
is massive. For example, roughly 10 million trades are performed
each day on the NASDAQ stock exchange. A significant proportion of
these trades are made by
high-
frequency traders. These entities
make on the order of thousands or more trades a day. However, the
stock-market factors that drive the decisions of
high-
frequency
traders are poorly understood. Recently, hybridized threshold
clustering (HTC) has been proposed as a way of clustering
large-to-massive datasets. In this report, we use three months of
NASDAQ HFT data – a dataset containing information on all trades of
120 different stocks including identifiers on whether the buyer
and/or seller were
high-
frequency traders – to investigate the
trading patterns of
high-
frequency traders, and we explore the use
of HTC to identify these patterns. We find that, while HTC can be
successfully performed on the NASDAQ HFT dataset, the amount of
information gleaned from this clustering is limited. Instead, we
show that an understanding of the habits of
high-
frequency traders
may be gained by looking at it{janky} trades – those in which
the number of shares traded is not a multiple of 10. We demonstrate
evidence that janky trades are more common for
high-
frequency
traders. Additionally, we suggest that a large number of small,
janky trades may help signal that a large trade will happen shortly
afterward.
Advisors/Committee Members: Michael Higgins.
Subjects/Keywords: Clustering; Stock
market dataset;
High-frequency trades
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APA ·
Chicago ·
MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhang, Z. (2018). Selected
results from clustering and analyzing stock market trade
data. (Masters Thesis). Kansas State University. Retrieved from http://hdl.handle.net/2097/39297
Chicago Manual of Style (16th Edition):
Zhang, Zhihan. “Selected
results from clustering and analyzing stock market trade
data.” 2018. Masters Thesis, Kansas State University. Accessed March 06, 2021.
http://hdl.handle.net/2097/39297.
MLA Handbook (7th Edition):
Zhang, Zhihan. “Selected
results from clustering and analyzing stock market trade
data.” 2018. Web. 06 Mar 2021.
Vancouver:
Zhang Z. Selected
results from clustering and analyzing stock market trade
data. [Internet] [Masters thesis]. Kansas State University; 2018. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/2097/39297.
Council of Science Editors:
Zhang Z. Selected
results from clustering and analyzing stock market trade
data. [Masters Thesis]. Kansas State University; 2018. Available from: http://hdl.handle.net/2097/39297
University of Toronto
30.
Munding, Chelsea.
Development of a 3 French Dual Frequency IVUS Catheter.
Degree: PhD, 2019, University of Toronto
URL: http://hdl.handle.net/1807/101744
► There is a need for imaging modalities capable of more fully visualizing the features of atherosclerotic plaque and monitoring treatments. Currently, only invasive modalities are…
(more)
▼ There is a need for imaging modalities capable of more fully visualizing the features of atherosclerotic plaque and monitoring treatments. Currently, only invasive modalities are able to precisely assess fibrous cap thickness, plaque size, the extent of positive remodelling, and the correct expansion of stents. No individual modality can visualize all of these features at the present time, and considerable effort has been made to develop hybrid imaging catheters for broader capabilities. In line with that goal, this thesis describes the development of a dual frequency intravascular ultrasound (DF IVUS) catheter incorporating a bidirectional transducer stack with centre frequencies of 30 and 80 MHz. 30 MHz is within the range of currently available clinical IVUS, and 80 MHz was chosen to provide the desired superficial resolution. The prototype was designed to have a clinically-relevant size and form factor to ensure its applicability for this purpose. The design and fabrication process are explained in detail, and the characterization results show the successful performance of the prototype with respect to the design criteria. Imaging of phantoms, in vitro human atherosclerotic coronary arteries and in vivo healthy porcine coronary arteries demonstrate that the prototype is able to provide complementary, coplanar images; with superficial axial resolution as low as 16 μm, lower-resolution depth penetration up to 6 mm, penetration through blood at both 30 and 80 MHz, and improved visualization of a stent relative to the vessel wall. Features of plaque and the vessel wall were well-visualized compared with conventional IVUS (30 MHz). These results suggest that DF IVUS is technologically and clinical feasible as a technique for improved coronary imaging. Other design approaches to DF IVUS may provide additional benefits, including contrast-enhanced imaging, and the procedures described here may be relevant to the development of these and other sub-millimetre ultrasound devices.
2020-07-21 00:00:00
Advisors/Committee Members: Foster, F. Stuart, Medical Biophysics.
Subjects/Keywords: Atherosclerosis; Dual frequency; High frequency; Intravascular imaging; Intravascular ultrasound; Transducers; 0986
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APA (6th Edition):
Munding, C. (2019). Development of a 3 French Dual Frequency IVUS Catheter. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/101744
Chicago Manual of Style (16th Edition):
Munding, Chelsea. “Development of a 3 French Dual Frequency IVUS Catheter.” 2019. Doctoral Dissertation, University of Toronto. Accessed March 06, 2021.
http://hdl.handle.net/1807/101744.
MLA Handbook (7th Edition):
Munding, Chelsea. “Development of a 3 French Dual Frequency IVUS Catheter.” 2019. Web. 06 Mar 2021.
Vancouver:
Munding C. Development of a 3 French Dual Frequency IVUS Catheter. [Internet] [Doctoral dissertation]. University of Toronto; 2019. [cited 2021 Mar 06].
Available from: http://hdl.handle.net/1807/101744.
Council of Science Editors:
Munding C. Development of a 3 French Dual Frequency IVUS Catheter. [Doctoral Dissertation]. University of Toronto; 2019. Available from: http://hdl.handle.net/1807/101744
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