repository:cmu

Carnegie Mellon University

1. Ke, Jiaying. Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1142

► This thesis contains theoretical development and experimental verification of the Horizontal Ribbon Growth (HRG) method for continuous silicon wafer manufacturing. In the HRG process, heat… (more)

▼ This thesis contains theoretical development and experimental verification of the Horizontal Ribbon Growth (HRG) method for continuous silicon wafer manufacturing. In the HRG process, heat is removed through the top surface of the molten silicon pool, meanwhile, a thin silicon solid sheet is produced and extracted continuously, in this way minimizing material losses. We assessed three technical issues regarding the design and operation of the proposed process using mathematical modeling approaches: the overall process modeling, corrugated wavy interface, and front wedge formation. A Mathematical field model that governs the mass, momentum and energy balances is developed to provide a platform for alternative cooling/heating setups evaluation, as well as, various candidate process designs. The results of our study showed a relationship between the pulling velocity and the thickness of the ribbon that is qualitatively in agreement with available experimental results. A linear stability theory is used to investigate the wavy instability occurred at the wafer-melt interface. The conditions for the onset of stability were identified theoretically and numerically on the basis of diffusion-convection equations for the thermal, solutal fields coupled with the Navier-Stokes equation describing the flow field in the molten pool near the interface. The interface stability conditions of the system under different operating conditions were examined to establish the optimal range of operation. A cellular automata algorithm is coupled with finite difference scheme to study to evolution of crystallization for the system. The formation of dendrites at the crystal front, non-smooth/unstable solid-liquid interface, and sharp wedge were simulated. We demonstrate a more homogeneous segregation of impurities in the bottom portion of the resulting wafer, while an aggressive cooling rate results in an unsmooth interface formation. Two experimental pilot facilities were developed and utilized to validate theoretical findings and study the scale-up of the proposed process. In particular, an ice machine was built as a prototype to examine the feasibility of the process and test different preliminary design ideas, while a silicon pilot facility is utilized for experimenting with extracting silicon wafers continuously from the melt.

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APA (6^th Edition):

Ke, J. (2018). Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1142

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

Chicago Manual of Style (16^th Edition):

Ke, Jiaying. “Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1142.

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

MLA Handbook (7^th Edition):

Ke, Jiaying. “Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers.” 2018. Web. 26 Feb 2021.

Vancouver:

Ke J. Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1142.

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

Council of Science Editors:

Ke J. Process Design and Modeling of the Horizontal Ribbon Growth Method for Continuous Production of Silicon Wafers. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1142

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

Carnegie Mellon University

2. Armiger, Travis J. Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1143

► Mammalian cells are known to respond to both extra- and intra- cellular forces as well as the physical properties of the surrounding tissue. There is… (more)

Subjects/Keywords: Epithelial; Lamin; Monolayer; Nucleus; Particle Tracking; Spectrin

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APA (6^th Edition):

Armiger, T. J. (2018). Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1143

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

Chicago Manual of Style (16^th Edition):

Armiger, Travis J. “Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1143.

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

MLA Handbook (7^th Edition):

Armiger, Travis J. “Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell.” 2018. Web. 26 Feb 2021.

Vancouver:

Armiger TJ. Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1143.

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

Council of Science Editors:

Armiger TJ. Force Propagation in Mammalian Cell Systems and the Relevance of the Mechanically Integrated Cell. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1143

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

Carnegie Mellon University

3. Bechtel, Toni M. Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1144

► We calculate the stress response, or rheology, of a micro-mechanical model suspension of rigid, Brownian spheroids in a Newtonian fluid in an oscillatory shear flow.… (more)

▼ We calculate the stress response, or rheology, of a micro-mechanical model suspension of rigid, Brownian spheroids in a Newtonian fluid in an oscillatory shear flow. The straining and rotation components of a linear flow affects the microstructure, or particle orientation in space and time, and thus, the suspension stress. A statistical description of the microstructure is given by an orientation probability distribution function, which quantifies the likelihood of a particle possessing a particular orientation at an instance in time. The evolution of the microstructure results from the memory of the material, advection from the flow, and rotational Brownian motion. The macroscopic stress response is calculated from ensemble averages of the stresslet weighted by the orientation distribution function. First, we calculate the linear stress response of a dilute suspension of rigid, spheroidal, self-propelled particles under a small-amplitude oscillatory shear deformation using regular perturbation theory. The particle activity leads to a direct contribution to the material stress, via self-propulsion, and an indirect contribution due to correlated tumbling events. The mechanism and strength of self-propulsion and correlation between tumbling events can be determined from the linear stress response of an active suspension. Next, we develop a framework for determining the relaxation moduli of a viscoelastic material through the combination of a memory integral expansion and a multimode-frequency oscillatory shear flow. We analytically determine the first nonlinear relaxation modulus of the model suspension through a comparison of the second normal stress difference from the microstructural stress response, calculated via regular perturbation theory, and a co-rotational memory integral expansion. The stress response of the system is reconstructed for the start-up and cessation of steady simple shear and uniaxial extension. Finally, we numerically calculate the nonlinear viscoelasticity of the model system subject to a large-amplitude oscillatory shear flow. In a sufficiently strong flow with oscillation frequency comparable to the material relaxation rate, secondary overshoots in the stress response occur. We attribute the origin of secondary overshoots to particles undergoing a Jeffery orbit during a (half) cycle of the oscillation, analogous to the case of non-Brownian spheroids in steady shear flow.

Subjects/Keywords: >; memory; Micro-mechanical modeling; microstructure; oscillatory shear; rheology; viscoelasticity

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

APA (6^th Edition):

Bechtel, T. M. (2018). Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1144

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

Chicago Manual of Style (16^th Edition):

Bechtel, Toni M. “Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1144.

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

MLA Handbook (7^th Edition):

Bechtel, Toni M. “Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow.” 2018. Web. 26 Feb 2021.

Vancouver:

Bechtel TM. Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1144.

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

Council of Science Editors:

Bechtel TM. Micro-mechanical Modeling of Brownian Spheroids in Oscillatory Shear Flow. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1144

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

Carnegie Mellon University

4. Eason, John P. A Trust Region Filter Algorithm for Surrogate-based Optimization.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1145

► Modern nonlinear programming solvers can efficiently handle very large scale optimization problems when accurate derivative information is available. However, black box or derivative free modeling… (more)

▼ Modern nonlinear programming solvers can efficiently handle very large scale optimization problems when accurate derivative information is available. However, black box or derivative free modeling components are often unavoidable in practice when the modeled phenomena may cross length and time scales. This work is motivated by examples in chemical process optimization where most unit operations have well-known equation oriented representations, but some portion of the model (e.g. a complex reactor model) may only be available with an external function call. The concept of a surrogate model is frequently used to solve this type of problem. A surrogate model is an equation oriented approximation of the black box that allows traditional derivative based optimization to be applied directly. However, optimization tends to exploit approximation errors in the surrogate model leading to inaccurate solutions and repeated rebuilding of the surrogate model. Even if the surrogate model is perfectly accurate at the solution, this only guarantees that the original problem is feasible. Since optimality conditions require gradient information, a higher degree of accuracy is required. In this work, we consider the general problem of hybrid glass box/black box optimization, or gray box optimization, with focus on guaranteeing that a surrogate-based optimization strategy converges to optimal points of the original detailed model. We first propose an algorithm that combines ideas from SQP filter methods and derivative free trust region methods to solve this class of problems. The black box portion of the model is replaced by a sequence of surrogate models (i.e. surrogate models) in trust region subproblems. By carefully managing surrogate model construction, the algorithm is guaranteed to converge to true optimal solutions. Then, we discuss how this algorithm can be modified for effective application to practical problems. Performance is demonstrated on a test set of benchmarks as well as a set of case studies relating to chemical process optimization. In particular, application to the oxycombustion carbon capture power generation process leads to significant efficiency improvements. Finally, extensions of surrogate-based optimization to other contexts is explored through a case study with physical properties.

Subjects/Keywords: Model Reduction; Multi-scale Engineering; Optimization; Process Systems; Surrogate Models

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APA (6^th Edition):

Eason, J. P. (2018). A Trust Region Filter Algorithm for Surrogate-based Optimization. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1145

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

Chicago Manual of Style (16^th Edition):

Eason, John P. “A Trust Region Filter Algorithm for Surrogate-based Optimization.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1145.

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

MLA Handbook (7^th Edition):

Eason, John P. “A Trust Region Filter Algorithm for Surrogate-based Optimization.” 2018. Web. 26 Feb 2021.

Vancouver:

Eason JP. A Trust Region Filter Algorithm for Surrogate-based Optimization. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1145.

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

Council of Science Editors:

Eason JP. A Trust Region Filter Algorithm for Surrogate-based Optimization. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1145

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

Carnegie Mellon University

5. Kasiewicz, Lisa N. siRNA Loaded Lipidoid Nanoparticles and the Immune System.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1146

► Delivery vehicles are necessary for many therapeutics to overcome the various challenges in their path. It is clear, however, that the relationship between delivery vehicles… (more)

▼ Delivery vehicles are necessary for many therapeutics to overcome the various challenges in their path. It is clear, however, that the relationship between delivery vehicles and the immune system is a complex one. One such delivery vehicle is the lipidoid nanoparticle, which has been shown to be potent in several cell types. This thesis details the first time lipidoids have been used for wound delivery, and demonstrates the successful silencing of an inflammatory protein, TNFα, in the context of diabetic ulcers. Knockdown is seen in an in vitro macrophage-fibroblast coculture model, as well as in nondiabetic and diabetic mice wound models. Lipidoids silence roughly half of the TNFα gene expression in the diabetic wound and have been shown to help the wound close faster than untreated controls. Of course, immune activation can decrease therapeutic efficacy or trigger dangerous reactions in the patient. Learning more about what chemical moieties cause an immune response would allow for the design of a particle that could better resist immune clearance and avoid the creation of a secondary response. This thesis investigated the effect of a lipidoid library on the immune system using a two pronged approach. The lipidoids were first tested against human peripheral blood mononuclear cells and then were injected into mice to probe the in situ immune response. Several types of B cells were examined in this latter case, namely germinal center B cells, plasma cells, and memory B cells. A T cell dependent response occurred, favoring memory B cells for most of the lipidoids tested. There was an increase in free antibody in the blood that reflected this increase in antibody producing cells. Nitrogen rings and carbon tail lengths of eleven and twelve carbons were particularly reactive, though it appears that the amine head group determines immune response more than the tail. Further work will analyze whether these increases in immune cells reflect a loss of therapeutic efficacy, as current ramifications are unclear. An in-depth T cell subset analysis with flow cytometry would also help complete the picture.

Subjects/Keywords: diabetic foot ulcer; immune response; lipidoid nanoparticle; RNA interference; siRNA

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APA (6^th Edition):

Kasiewicz, L. N. (2018). siRNA Loaded Lipidoid Nanoparticles and the Immune System. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1146

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

Chicago Manual of Style (16^th Edition):

Kasiewicz, Lisa N. “siRNA Loaded Lipidoid Nanoparticles and the Immune System.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1146.

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

MLA Handbook (7^th Edition):

Kasiewicz, Lisa N. “siRNA Loaded Lipidoid Nanoparticles and the Immune System.” 2018. Web. 26 Feb 2021.

Vancouver:

Kasiewicz LN. siRNA Loaded Lipidoid Nanoparticles and the Immune System. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1146.

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

Council of Science Editors:

Kasiewicz LN. siRNA Loaded Lipidoid Nanoparticles and the Immune System. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1146

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

Carnegie Mellon University

6. Nelson, Diane L. Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1147

► Inhaled drug delivery is currently the gold standard for treating many respiratory diseases. However, improved treatments are needed for lung diseases like Cystic Fibrosis (CF)… (more)

▼ Inhaled drug delivery is currently the gold standard for treating many respiratory diseases. However, improved treatments are needed for lung diseases like Cystic Fibrosis (CF) and Acute Respiratory Distress Syndrome (ARDS), where mucus or fluid build-up in the lung limits ventilation and, thus, delivery of inhaled drugs. Delivery is most needed in the diseased or damaged regions of the lung, but if an area is not ventilated, inhaled drug will simply not reach it. To overcome this, this research proposes delivering drugs to the lungs within a perfluorocarbon (PFC) liquid. The lungs will be filled with a reverse emulsion containing a disperse phase of aqueous drugs within the bulk PFC and then ventilated. The PFC functions as both a respiratory medium, providing gas exchange, and as a delivery vehicle, providing a more uniform deposition of drugs. After treatment, the highly volatile PFCs are exhaled, returning the patient to normal respiration. This technique improves upon current therapies as follows. First, drugs are delivered directly to where they are needed, yielding higher concentrations in the lung and lower systemic concentrations. Second, PFCs are ideal for washing out lung exudate and mucus. The low surface tension and high density of PFC allows it to easily penetrate plugged or collapsed alveoli, detach infected mucus from the airway walls, and force these fluids to the top of the lungs where they can then be removed via suction. Mucus and exudate removal should allow drugs to penetrate previously plugged airways during emulsion delivery and subsequent treatment with inhaled therapies. Thus, drug delivery via emulsion would be used as a pre-treatment to enhance inhaled or systemic drug therapy. Third, PFC’s anti-inflammatory properties help return to normal lung function. This research examines two applications of this technology: delivery of antibiotics to combat respiratory infections (antibacterial perfluorocarbon ventilation, APV) or delivery of growth factors to enhance alveolar repair (perfluorocarbon emulsions for alveolar repair, PEAR). This work represents an in-depth analysis of the emulsions used during APV and PEAR. Initial efforts evaluated emulsion efficacy under in vitro setting that better simulated lung in vivo antibiotic delivery. The subsequent studies utilized an in vivo rat model of bacterial respiratory infection to validate the effects of emulsion on pharmacokinetics and to assess APVs potential treatment benefits. Lastly, in vitro methods of cellular response assessed the utility of delivering growth factors in PEAR. Significant advancements were made in optimizing the emulsion as a viable means of pulmonary drug delivery. Final efforts resulted in a promising emulsion formulation that overcame the quick transport of tobramycin away from the lung and successfully reduced pulmonary bacterial load in vivo. In vitro applications of PEAR showed the emulsions posed a significant barrier to the availability and, thus, the biological effect of lysophosphatidic acid growth factors. Further…

Subjects/Keywords: acute lung injury; cystic fibrosis; drug delivery; fluorosurfactant; liquid ventilation; perfluorocarbon

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APA (6^th Edition):

Nelson, D. L. (2018). Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1147

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

Chicago Manual of Style (16^th Edition):

Nelson, Diane L. “Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1147.

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

MLA Handbook (7^th Edition):

Nelson, Diane L. “Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure.” 2018. Web. 26 Feb 2021.

Vancouver:

Nelson DL. Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1147.

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

Council of Science Editors:

Nelson DL. Pulmonary Drug Delivery via Reverse Perfluorocarbon Emulsions: A Novel Method for Bacterial Respiratory Infections and Acute Respiratory Failure. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1147

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

Carnegie Mellon University

7. Yang, Baojiang. Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1149

► Digitization has been pervasively reshaping the landscape of home-based telecommunication industries. The massive disruptive challenges call for telecom companies to react with efficient strategic managerial… (more)

▼ Digitization has been pervasively reshaping the landscape of home-based telecommunication industries. The massive disruptive challenges call for telecom companies to react with efficient strategic managerial policies. Meanwhile, how consumer decision makings and welfare are impacted by such policies often remains complicated and non-transparent to policy makers. My thesis aims at leveraging large-scale empirical data to investigate the impacts of several prevalent firm initiated strategies on both sides of the market, i.e. consumers and firms. The thesis is comprised of three studies focusing on consumer switch, search and purchase behaviors. The first study, centering at consumer switching behaviors, investigates the impact of lock in shortening policies on both firm profits and consumer welfare in home-based telecommunication service market. Using household level data from a large telecommunications service provider, we show that a market level policy that shortens the lock-in period from the status quo can decrease the profits on the firms side more than it increases consumer surplus. This is majorly caused by the substantial acquisition costs associated with user switching and service initiation. As a result if regulators shorten lock-in periods but then firms respond by collaboratively increasing prices to recover their rate of return, the consumers, as the analyses indicate, may be worse off compared to the world in which lock-in periods do not change. Therefore lock-in reduction policy need to be paired with a policy precluding operators from increasing prices too much. The later two studies jointly examine consumer’s search and purchase behaviors in social environment. With a wide scope of services, telecommunication service providers can often leverage their knowledge on consumer’s social environment to reshape consumer choices. We aim to understand how consumers combine different sources of social information, one from friends versus one from the crowd, as a function of how close they are to the point of conversion. We developed a dynamic structural econometric model that jointly describes consumer information search and product purchase while taking into account sequential arrival of information and non-negligible search costs. The model is then instantiated on two connected yet distinct empirical contexts, where consumers shop for movies to watch on home screens. The first empirical context (discussed in the second study in this thesis) lies in an observational setting, where we studied individual level clickstream and transactional data from a Video-on- Demand service platform operated by a large telecommunication service provider. Later in the third study, we created an artificial movie market and leveraged a randomized web experiment to further study the research questions with more solid identification support. We find that, in both contexts, consumers seem to start by browsing products they heard about from friends. The popularity signals become more relevant when consumers getting closer to the…

Subjects/Keywords: consumer behaviors; information search; regulations; social influence; social network; telecommunications

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

APA (6^th Edition):

Yang, B. (2018). Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1149

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

Chicago Manual of Style (16^th Edition):

Yang, Baojiang. “Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1149.

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

MLA Handbook (7^th Edition):

Yang, Baojiang. “Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors.” 2018. Web. 26 Feb 2021.

Vancouver:

Yang B. Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1149.

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

Council of Science Editors:

Yang B. Essays on Telecommunications Management: Understanding Consumer Switch, Search and Purchase Behaviors. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1149

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

Carnegie Mellon University

8. Yu, Xiaoxiao. High Throughput Assessment of Multicomponent Alloy Materials.

Degree: 2018, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1150

► Multicomponent metal alloys play an essential role in many technologies and their properties must be optimized by rational selection of the alloy’s components and its… (more)

▼ Multicomponent metal alloys play an essential role in many technologies and their properties must be optimized by rational selection of the alloy’s components and its fractional composition of each. High-throughput materials synthesis allows us to prepare Composition Spread Alloy Films (CSAFs), sample libraries that contains all possible compositions of a binary or ternary alloy. In our lab, a Rotatable Shadow Mask (RSM) – CSAF deposition tool has been developed for the creation of CSAFs. Such CSAFs can be prepared with composition gradients and/or thickness gradients in arbitrarily controlled directions and on a variety of substrates. Once prepared, the CSAF libraries can be characterized thoroughly using a variety of highthroughput spectroscopic methods. Their bulk composition is mapped across the library using Energy Dispersive X-ray spectroscopy (EDX). The near-surface compositions are mapped across composition space using X-ray Photoemission Spectroscopy (XPS). Finally, the electronic structure can be mapped using UV photoemission spectroscopy (UPS) and valence band XPS. Once characterized, these CSAFs are being used for high-throughput studies of alloy catalysis and thermal properties of the alloys and of alloy-substrate interfaces. First of all, PdzCu1-z CSAF was prepared to show that alloy nanoparticles (aNPs) and thin films can adopt phases that differ from those of the corresponding bulk alloy. The mapping of XPS-derived core level binding energy shifts across PdzCu1-z SCSNaP library shows a promising result that the FCC phase can be dimensionally stabilized over the composition range where B2 phase exists in the bulk. This observation can potentially improve the performance of PdzCu1-z NP catalysts in H2 separation. Secondly, the relationship between catalyst activity-electronic structure-composition has been investigated. A high throughput characterization of electronic structure (valence band energy) of binary PdxAg1-x and ternary PdxCuyAu1-x-y CSAFs were performed by XPS. This XPS-derived valence band center is compared with UPS-derived data across PdxCuyAu1-x-y CSAFs. In addition, H2-D2 exchange reaction was studied on PdxAg1-x CASF. A higher HD formation rate is experimentally observed but cannot be predicted by the Langmuir-Hinshelwood model when the surface coverage is saturated. However, the proposed H2-D2 exchange mechanism (breakthrough model) involved with surface and subsurface hydrogen reaction is investigated to produce a same reaction order as Langmuir-Hinshelwood mechanism, which cannot explain the experimental observation. Furthermore, the thermal interface conductance (G) was studied as a function of metal alloy composition. A high-throughput approach to preparation, characterization, and measurement of G was also demonstrated to study the thermal property of alloyed materials. Our result in studying the G across the AuxY1-x (Y = Pd and Cu) CSAFs-dielectric interfaces has shown a linear relationship with alloy composition, which monotonically increases with decreasing Au (at. %). Lastly,…

Subjects/Keywords: Alloy; electronic structure; High throughput; interdiffusion; phase transition; thermal interface conductance

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APA (6^th Edition):

Yu, X. (2018). High Throughput Assessment of Multicomponent Alloy Materials. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1150

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

Chicago Manual of Style (16^th Edition):

Yu, Xiaoxiao. “High Throughput Assessment of Multicomponent Alloy Materials.” 2018. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/1150.

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

MLA Handbook (7^th Edition):

Yu, Xiaoxiao. “High Throughput Assessment of Multicomponent Alloy Materials.” 2018. Web. 26 Feb 2021.

Vancouver:

Yu X. High Throughput Assessment of Multicomponent Alloy Materials. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/1150.

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

Council of Science Editors:

Yu X. High Throughput Assessment of Multicomponent Alloy Materials. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1150

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

9. Tom, Michelle S. Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/603

► Since the 1970s, the percentage of the US population that is overweight and obese has increased significantly, with nearly 70% of American adults now overweight… (more)

▼ Since the 1970s, the percentage of the US population that is overweight and obese has increased significantly, with nearly 70% of American adults now overweight or obese (National Center for Health Statistics, 2013). The American Medical Association officially recognized obesity as a disease (American Medical Association, 2013) that afflicts approximately one out of every three adults in the US (National Center for Health Statistics, 2013). While the health implications of being overweight or obese are well established, the environmental impacts have not received equal attention. In light of this inattention, this dissertation analyzes the effects of the overweight and obese population on energy use, water withdrawals, greenhouse gas (GHG) emissions, and fuel costs through the US food supply system and transportation system. The first empirical chapter investigates the impacts of current US food consumption on energy use, water withdrawals, and GHG emissions. The purpose of this analysis is twofold: first, two top-down approaches are used to establish a range of life-cycle industrial energy use, water withdrawals, and GHG emissions in the US food supply system that are attributed to total food consumed by the US adult population. The two methods utilized are 1) economic input-output life-cycle assessment (EIO-LCA) and 2) process-based analysis. Second, the additional industrial energy use, water withdrawals, and GHG emissions required to support the extra Caloric intake of the US overweight and obese adult population are estimated. Extra Caloric intake estimates are developed using anthropometric data from the Centers for Disease Control (CDC) National Health and Nutrition Examination Survey. In 2012, 6.1-6.2 million TJ of cumulative energy use, 100-105 billion m3 of water withdrawals, and 600 million metric tons (MMT) CO2-eq were needed to provide food to the US adult population. Furthermore, 8-10% of total Caloric intake of adults were extra Calories consumed from overeating for overweight and obese adults. Providing these additional Calories resulted in 440,000-610,000 TJ of energy use, 7-10 billion m3 of water withdrawals, and 43-59 MMT CO2-eq. The second empirical chapter uses a bottom-up approach to measure the changes in energy use, water withdrawals, and GHG emissions associated with shifting from current US food consumption patterns to three dietary scenarios, which are based, in part, on the 2010 USDA Dietary Guidelines (US Department of Agriculture and US Department of Health and Human Services 2010). Amidst the current overweight and obesity epidemic in the US, the Dietary Guidelines provide food and beverage recommendations that are intended to help individuals achieve and maintain healthy weight. The three dietary scenarios examined include 1) reducing Caloric intake levels to achieve “normal” weight without shifting food mix, 2) switching current food mix to USDA recommended food patterns, without reducing Caloric intake, and 3) reducing Caloric intake levels and shifting current food mix to USDA…

…emissions associated with economic activity (Lave et al. 1995, Hendrickson et al. 2006, CMU…

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APA (6^th Edition):

Tom, M. S. (2015). Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/603

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

Chicago Manual of Style (16^th Edition):

Tom, Michelle S. “Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/603.

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

MLA Handbook (7^th Edition):

Tom, Michelle S. “Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems.” 2015. Web. 26 Feb 2021.

Vancouver:

Tom MS. Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/603.

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

Council of Science Editors:

Tom MS. Impacts of the Overweight and Obese on the US Food Supply and Transportation Systems. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/603

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

10. Regner, Keith T. On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/615

► Nondiffusive thermal transport occurs when length or time scales of a system are on the order of the mean free paths (MFPs) or lifetimes of… (more)

▼ Nondiffusive thermal transport occurs when length or time scales of a system are on the order of the mean free paths (MFPs) or lifetimes of the energy carriers. As a result, a local equilibrium temperature cannot be defined and the thermal transport properties of the system can no longer be taken as the bulk values. When system boundaries are decreased below energy carrier MFPs, nondiffusive transport can be described with a reduced, effective thermal conductivity. Heat dissipation in light emitting diodes and transistors is adversely impacted by reductions in thermal conductivity, while thermoelectric energy conversion devices benefit. In my PhD, I studied the physics governing nondiffusive thermal transport. In this dissertation I describe my contributions in nondiffusive thermal transport to the scientific community. First, I describe the development of broadband frequency domain thermoreflectance (BBFDTR), an experimental technique used to observe nondiffusive thermal transport in materials by creating length scales comparable to energy carrier MFPs. I use BB-FDTR to induce nondiffusive thermal transport in Si-based materials at device operating temperatures. I relate my measurements to the thermal conductivity accumulation function, a fundamental physical quantity that describes cumulative contributions to thermal conductivity from energy carriers with different MFPs. Using a first order interpretation of my data I show that 40±5% of the thermal conductivity of crystalline silicon at a temperature of 311 K comes from phonons with MFP > 1 μm. Additional BB-FDTR measurements on a 500 nm thick amorphous silicon film indicate propagating phonon-like modes that contribute more than 35±7% to thermal conductivity at a temperature of 306 K, despite atomic disorder. I also describe the development of multiple models that are used to refine the interpretation of BB-FDTR measurements and better understand nondiffusive thermal transport measurements. First, I the Boltzmann transport equation (BTE) analytically to explain how and why measurements of thermal conductivity change as a function of experimental length scales in BB-FDTR. My solution incorporates two experimentally defined length scales: thermal penetration depth and heating laser spot radius. Comparison of the BTE result with that from conventional heat diffusion theory enables a mapping of MFP-specific contributions to the measured thermal conductivity based on the experimental length scales. The result is used to re-interpret nondiffusive thermal conductivity measurements of silicon with first principles-based calculations of its thermal conductivity accumulation function. Next, I develop a solution to the two-temperature diffusion equation in axisymmetric cylindrical coordinates to model heat transport in thermoreflectance experiments. The solution builds upon prior solutions that account for two-channel diffusion in each layer of an N-layered geometry, but adds the ability to deposit heat at any location within each layer. I use this solution to account for…

…time at CMU was the invention and development of BB-FDTR, as described in Chapter 2 (and… …from my time at CMU is the measurement of kexp vs. Lp for Si-based materials at device…

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APA (6^th Edition):

Regner, K. T. (2016). On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/615

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

Chicago Manual of Style (16^th Edition):

Regner, Keith T. “On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/615.

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

MLA Handbook (7^th Edition):

Regner, Keith T. “On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity.” 2016. Web. 26 Feb 2021.

Vancouver:

Regner KT. On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/615.

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

Council of Science Editors:

Regner KT. On Nondiffusive Thermal Transport and Phonon Mean-Free-Path-Dependent Contributions to Thermal Conductivity. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/615

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

11. Wiese, Jason Stampfer. Evolving the Ecosystem of Personal Behavioral Data.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/624

► Personal data is everywhere. The widespread adoption of the Internet, fueled by the proliferation of smartphones and data plans, has resulted in an amazing amount… (more)

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APA (6^th Edition):

Wiese, J. S. (2015). Evolving the Ecosystem of Personal Behavioral Data. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/624

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

Chicago Manual of Style (16^th Edition):

Wiese, Jason Stampfer. “Evolving the Ecosystem of Personal Behavioral Data.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/624.

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

MLA Handbook (7^th Edition):

Wiese, Jason Stampfer. “Evolving the Ecosystem of Personal Behavioral Data.” 2015. Web. 26 Feb 2021.

Vancouver:

Wiese JS. Evolving the Ecosystem of Personal Behavioral Data. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/624.

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

Council of Science Editors:

Wiese JS. Evolving the Ecosystem of Personal Behavioral Data. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/624

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

12. Liu, Lei. Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/625

► Constructing spline models for isogeometric analysis is important in integrating design and analysis. Converting designed CAD (Computer Aided Design) models with B-reps to analysis-suitable volumetric… (more)

▼ Constructing spline models for isogeometric analysis is important in integrating design and analysis. Converting designed CAD (Computer Aided Design) models with B-reps to analysis-suitable volumetric T-spline is fundamental for the integration. In this thesis, we work on two directions to achieve this: (a) using Boolean operations and skeletons to build polycubes for feature-preserving high-genus volumetric T-spline construction; and (b) developing weighted T-splines with arbitrary degree for T-spline surface and volume modeling which can be used for analysis. In this thesis, we first develop novel algorithms to build feature-preserving polycubes for volumetric T-spline construction. Then a new type of T-spline named the weighted T-spline with arbitrary degree is defined. It is further used in converting CAD models to analysis-suitable volumetric T-splines. An algorithm is first developed to use Boolean operations in CSG (Constructive Solid Geometry) to generate polycubes robustly, then the polycubes are used to generate volumetric rational solid T-splines. By solving a harmonic field with proper boundary conditions, the input surface is automatically decomposed into regions that are classified into topologically either a cube or a torus. Two Boolean operations, union and difference, are performed with the primitives and polycubes are generated by parametric mapping. With polycubes, octree subdivision is carried out to obtain a volumetric T-mesh. The obtained T-spline surface is C2-continuous everywhere except the local region surrounding irregular nodes, where the surface continuity is elevated from C0 to G1. B´ezier elements are extracted from the constructed solid T-spline models, which are further used in isogeometric analysis. The Boolean operations preserve the topology of the models inherited from design and can generate volumetric T-spline models with better quality. Furthermore, another algorithm is developed which uses skeleton as a guidance to the polycube construction. From the skeleton of the input model, initial cubes in the interior are first constructed. By projecting corners of interior cubes onto the surface and generating a new layer of boundary cubes, the entire interior domain is split into different cubic regions. With the splitting result, octree subdivision is performed to obtain T-spline control mesh or T-mesh. Surface features are classified into three groups: open curves, closed curves and singularity features. For features without introducing new singularities like open or closed curves, we preserve them by aligning to the parametric lines during subdivision, performing volumetric parameterization from frame field, or modifying the skeleton. For features introducing new singularities, we design templates to handle them. With a valid T-mesh, we calculate rational trivariate T-splines and extract B´ezier elements for isogeometric analysis. Weighted T-spline basis functions are designed to satisfy partition of unity and linear independence. The weighted T-spline is proved to be…

Subjects/Keywords: Volumetric T-spline Construction; Feature Preservation; Weighted T-spline; Extraordinary Node; Arbitrary Degree; Isogeometric Analysis

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APA (6^th Edition):

Liu, L. (2015). Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/625

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

Chicago Manual of Style (16^th Edition):

Liu, Lei. “Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/625.

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

MLA Handbook (7^th Edition):

Liu, Lei. “Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree.” 2015. Web. 26 Feb 2021.

Vancouver:

Liu L. Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/625.

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

Council of Science Editors:

Liu L. Volumetric T-spline Construction for Isogeometric Analysis – Feature Preservation, Weighted Basis and Arbitrary Degree. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/625

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

13. Wu, Wei-Tao. Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/635

► In this thesis several blood related problems are studied: 1. Malaria-infected, the removal of parasitized red blood cells (pRBCs) using a magnetic force; 2. A… (more)

▼ In this thesis several blood related problems are studied: 1. Malaria-infected, the removal of parasitized red blood cells (pRBCs) using a magnetic force; 2. A new mathematical model for thrombus growth, which incorporates the thrombus-blood interaction, shear induced platelets activation, shear induced platelets embolization and deposited platelets stabilization, is developed, and a successful direct numerical prediction of thrombus formation in an axial blood pump is obtained. According to our knowledge, this is the first time such a study has been performed ; 3. Based on the application of Mixture Theory (or Theory of Interacting Continua), a multiphase model for blood flow is derived, and a new viscosity term, which considers the effect of shear stress and volume fraction of RBCs, is introduced. First, a blood filter system, mPharesis™ system, that will allow the removal of toxic malariainfected, parasitized RBCs (pRBCs or i-RBCs) from circulation using magnetic force is studied. The problem is modeled as a multi-component flow system using CFD-DEM method, where plasma is treated as a Newtonian fluid, the RBCs and pRBCs are modeled as soft-sphere solid particles which move under the influence of the plasma, other RBCs and the magnetic field. The simulation results show that for a channel with nominal height of 100 microns the addition of upstream constriction of 80% improved the stratification by 111% (from 28% to 139%); and a downstream diffuser reduced remixing, hence improved efficiency of stratification to 260%. Second, based on the Sorenson’s model of thrombus formation [1, 2], a new mathematical model describing the process of thrombus growth is developed. In this model the blood is treated as a Newtonian fluid, and the transport and reactions of the chemical and biological species are modeled using CRD (convection-reaction-diffusion) equations. A computational fluid dynamic (CFD) solver for the mathematical model is developed using the libraries of OpenFOAM®. Applying the CFD solver, several representative benchmark problems are studied: rapid thrombus growth in vivo by injecting Adenosine diphosphate (ADP) using iontophoretic method and thrombus growth in rectangular microchannel with crevices. Very good agreements between the numerical and the experimental results validate the model and indicate its potential to study a host of complex and practical problems in the future. Then applying the model, thrombus growth in an axial blood pump is studied. First, the flow field analysis in the blood pump is studied using visualization and numerical simulations. Then applying the thrombus model, a direct prediction of the thrombus growth is performed. The simulation shows a very good agreement with clinical observations. For reducing the computational cost, a dimensionally-reduced model is also developed, based on the complete thrombus model. The dimensionally-reduced model shows good capability to predict the thrombus deposition in blood pump as well. And finally, for describing the multiphase characteristics of…

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APA (6^th Edition):

Wu, W. (2015). Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/635

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

Chicago Manual of Style (16^th Edition):

Wu, Wei-Tao. “Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/635.

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

MLA Handbook (7^th Edition):

Wu, Wei-Tao. “Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow.” 2015. Web. 26 Feb 2021.

Vancouver:

Wu W. Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/635.

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

Council of Science Editors:

Wu W. Theoretical and Computational Studies on Thrombus Formation and Multiphase Characteristics of Blood Flow. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/635

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

14. Yan, Miaolei. Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/650

La0.7Sr0.3MnO3 (LSM) is a perovskite oxide material that possesses many interesting electromagnetic and electrochemical properties, making it desirable as magnetic tunnel junction (MTJ) and solid oxide fuel cell (SOFC) electrodes.

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APA (6^th Edition):

Yan, M. (2015). Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/650

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

Chicago Manual of Style (16^th Edition):

Yan, Miaolei. “Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/650.

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

MLA Handbook (7^th Edition):

Yan, Miaolei. “Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films.” 2015. Web. 26 Feb 2021.

Vancouver:

Yan M. Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/650.

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

Council of Science Editors:

Yan M. Defect Analysis and Microstructural Effects on the Surface Exchange Properties of La0.7Sr0.3MnO3(LSM) Epitaxial Thin Films. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/650

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

15. Jablin, Michael. Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/656

Recent simulations have indicated that the traditional Helfrich-Canham model for topographical fluctuations in fluid phase biomembranes should be enriched to include molecular tilt. Experimental evidence supporting the aforementioned enrichment is reported.

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APA (6^th Edition):

Jablin, M. (2015). Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/656

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

Chicago Manual of Style (16^th Edition):

Jablin, Michael. “Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/656.

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

MLA Handbook (7^th Edition):

Jablin, Michael. “Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers.” 2015. Web. 26 Feb 2021.

Vancouver:

Jablin M. Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/656.

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

Council of Science Editors:

Jablin M. Tilt-Dependent Analysis of Diffuse X-ray Scattering from Oriented Stacks of Fluid Phase Lipid Bilayers. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/656

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

16. Xu, Zhongnan. Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/673

► The development of active and inexpensive catalysts is vital for progress in technologies related to efficient energy generation, storage, and utilization. Transition metal oxides (TMOs)… (more)

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APA (6^th Edition):

Xu, Z. (2016). Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/673

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

Chicago Manual of Style (16^th Edition):

Xu, Zhongnan. “Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/673.

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

MLA Handbook (7^th Edition):

Xu, Zhongnan. “Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides.” 2016. Web. 26 Feb 2021.

Vancouver:

Xu Z. Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/673.

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

Council of Science Editors:

Xu Z. Towards Accurate Predictions and Mechanistic Understanding of the Catalytic Activity of Transition Metal Oxides. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/673

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

17. Gong, Peng. Ultrasonic Signal Processing for Structural Damage Detection and Quantification.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/674

► The operation of our society depends heavily on infrastructure systems. To prevent failures and to reduce costs of maintenance, structural health monitoring (SHM) systems have… (more)

▼ The operation of our society depends heavily on infrastructure systems. To prevent failures and to reduce costs of maintenance, structural health monitoring (SHM) systems have been implemented on an increasing number of infrastructure systems. SHM systems have the potential to give reliable prediction of structural deterioration with less human safety risk and labor costs, and without interruption of normal operations. In the field of SHM, many techniques have been proposed in recent decades. Among these techniques, ultrasonic testing has been widely used for damage characterization in structures and materials. However, there remain many challenges in real-world SHM applications. For example, temperature variations can cause a significant decrease in performance of ultrasonic testing. Although there exist some temperature compensation techniques to improve the performance of ultrasonic testing under temperature variations, these techniques have their own limitations. This dissertation will focus on novel ultrasonic signal processing techniques for damage detection, quantification and temperature compensation. In Chapter 2, I will propose a modified optimal signal stretching (OSS) method and an singular value decomposition (SVD) method to solve the temperature compensation problem, where the OSS method (in its original form) failed to perform well for damage detection. In Chapter 3, I will study the statistical orthogonal relationship between temperature-induced and damage-induced ultrasonic change signals. The orthogonal relationship can be used to explain why SVD performs well under varying temperature conditions and why it also has the potential (under some conditions) to be directly used for damage detection and quantification. In Chapter 4, I viii will study the ultrasonic time-of-flight diffraction technique, which is used to quantify wall thickness loss of thick-walled aluminum tubes, because the conventional pulse-echo method did not perform well in my target application. In Chapter 5, I will propose a novel ultrasonic passband technique to quantify the alkali-silica reaction (ASR) caused cracking damage in concrete structures. This technique is based on the ultrasonic wave filtering effects of cracks in concrete. With the progress of ASR caused cracking damage in concrete, more high frequency components of ultrasonic waves are filtered out than low frequency components. The research work in this dissertation has the potential to help advance ultrasonic SHM techniques, to improve the real-world performance of ultrasonic SHM, to prevent failures of infrastructure systems, and to reduce the costs of maintenance if the proposed ultrasonic techniques can be implemented in real infrastructure systems in the future. However, some future work still needs to be done in order to implement the techniques studied in this dissertation in real-world applications.

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APA (6^th Edition):

Gong, P. (2015). Ultrasonic Signal Processing for Structural Damage Detection and Quantification. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/674

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

Chicago Manual of Style (16^th Edition):

Gong, Peng. “Ultrasonic Signal Processing for Structural Damage Detection and Quantification.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/674.

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

MLA Handbook (7^th Edition):

Gong, Peng. “Ultrasonic Signal Processing for Structural Damage Detection and Quantification.” 2015. Web. 26 Feb 2021.

Vancouver:

Gong P. Ultrasonic Signal Processing for Structural Damage Detection and Quantification. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/674.

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

Council of Science Editors:

Gong P. Ultrasonic Signal Processing for Structural Damage Detection and Quantification. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/674

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

18. McCann, Michael T. Tools for Automated Histology Image Analysis.

Degree: 2015, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/678

► In this thesis, we present three image processing tools inspired by and designed for histology image analysis. Histology, which is the examination of biological tissue… (more)

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APA (6^th Edition):

McCann, M. T. (2015). Tools for Automated Histology Image Analysis. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/678

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

Chicago Manual of Style (16^th Edition):

McCann, Michael T. “Tools for Automated Histology Image Analysis.” 2015. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/678.

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

MLA Handbook (7^th Edition):

McCann, Michael T. “Tools for Automated Histology Image Analysis.” 2015. Web. 26 Feb 2021.

Vancouver:

McCann MT. Tools for Automated Histology Image Analysis. [Internet] [Thesis]. Carnegie Mellon University; 2015. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/678.

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

Council of Science Editors:

McCann MT. Tools for Automated Histology Image Analysis. [Thesis]. Carnegie Mellon University; 2015. Available from: http://repository.cmu.edu/dissertations/678

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

19. Sun, Zhongling. Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/687

► Morphogenesis, the process by which the tissues and organs of the embryo are properly shaped, is a fundamental feature of development. In the sea urchin,… (more)

▼ Morphogenesis, the process by which the tissues and organs of the embryo are properly shaped, is a fundamental feature of development. In the sea urchin, the formation of the calcified enodoskeleton is a major morphogenetic event. Differentiation of the skeletogenic primary mesenchyme cells (PMCs) has been considered to occur in two phases: the autonomous specification of PMCs followed by signal-dependent patterning of PMCs and the embryonic skeleton they produce. Autonomous specification creates a homogenous population of PMCs, but the later differentiation of these cells is influenced by extrinsic signals that provide essential positional information. Recent studies showed that ectodermal growth factors are critically involved in the guidance of PMC migration and skeletal differentiation. However, a better understanding of the various signaling pathways that regulate skeletogenesis and their role in PMC gene expression remains to be established. This study examines the regulation of morphogenesis by signaling pathways, using skeletogenesis in the sea urchin embryo as a model. The aim of this study was to identify and study the roles of extrinsic signals in regulating PMC gene expression, focusing on the later, signal-dependent phase of PMC differentiation. By analyzing and classifying spatial expression patterns of 39 genes preferentially expressed in PMCs, I find that: 1) these genes are expressed non-uniformly within the PMC syncytium, reflecting a widespread influence of locally activated signals; 2) regions with elevated gene expression correlate with sites of rapid biomineral deposition at each stage; 3) non-uniform expression of genes within the PMC syncytium is controlled by multiple signal in a precise temporal sequence. I also provide evidence that ectoderm-derived VEGF signaling regulates gene expression in PMCs via the MAPK pathway on the ventral side of the embryo. Additionally, my work has identified an essential role for TGF-β signaling in skeletogenesis. Previous studies indicate that a complete repertoire of TGF-β signaling components is present in the sea urchin genome and TgfbrII mRNA is preferentially expressed in PMCs at the early gastrula stage. In this study, I show that TgfbrII mRNA is specifically expressed in the PMC lineage from the hatched blastula to the mid-gastrula stage. Perturbation experiments indicate that TgfbrII is activated by the single, sensu stricto TGF-β ligand in sea urchins and is required for skeletogenesis in the sea urchin embryo. I also show that the late activity of Alk4/5/7, the putative Type I receptor, regulates skeletogenesis in a dose-dependent manner. Isolation and in vitro culture of PMCs demonstrates that both Alk4/5/7 and TgfbrII function cell autonomously in these cells. I provide evidence that TGF-β-TgfbrII signaling is not involved in dorsal-ventral axis patterning or PMC specification; instead, this pathway plays a selective role in later skeletal patterning. Taken as a whole, my research demonstrates that skeletogenesis is regulated by a much more…

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APA (6^th Edition):

Sun, Z. (2016). Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/687

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

Chicago Manual of Style (16^th Edition):

Sun, Zhongling. “Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/687.

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

MLA Handbook (7^th Edition):

Sun, Zhongling. “Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo.” 2016. Web. 26 Feb 2021.

Vancouver:

Sun Z. Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/687.

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

Council of Science Editors:

Sun Z. Signal-Dependent Regulation of Skeletogenesis in the Sea Urchin Embryo. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/687

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

20. Cummings, Chad S. High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/692

► Proteins and protein-based materials are used for a wide range of therapeutic, diagnostic, and biotechnological applications. Still, the inherent instability of proteins in non-native environments… (more)

▼ Proteins and protein-based materials are used for a wide range of therapeutic, diagnostic, and biotechnological applications. Still, the inherent instability of proteins in non-native environments greatly limits the applications in which they are effective. In order to increase their utility, proteins are often modified, either biologically or chemically, to manipulate their bioactivity and stability profiles. In this work, covalent attachment of polymers to the enzyme chymotrypsin was used to predictably tailor protein bioactivity and stability. Specifically, atom transfer radical polymerization (ATRP) based polymer-based protein engineering (PBPE) was used to grow polymers directly from the surface of chymotrypsin. First, the temperature responsive polymers poly(N-isopropyl acrylamide) (pNIPAM), which has a lower critical solution temperature (LCST) and poly(dimethylamino propane sulfonate) (pDMAPS), which has an upper critical solution temperature (UCST), were separately grown from chymotrypsin. The temperature responsive properties of the polymers were conserved in the protein-polymer conjugates, and chymotrypsin bioactivity, productivity, and substrate specificity were predictably tailored at different temperatures depending on the structural organization of the polymers. Next, a dual block polymer-chymotrypsin conjugate was synthesized by growing poly(sulfobetaine methacrylamide) (pSBAm)-block-pNIPAm conjugates from the surface of chymotrypsin. The CT-pSBAm-b-pNIPAm conjugates showed temperature dependent kinetics, due to UCST or LCST driven polymer collapse at high and low temperature. Most interestingly, the dual block conjugates were dramatically more stable than native chymotrypsin to low pH. In order to further investigate the effect of polymer conjugation on chymotrypsin stability at low pH, four distinct and uniquely charged polymers were grown from the surface of chymotrypsin. With these new conjugates, we confirmed that chymotrypsin low pH stability was dependent on the chemical structure of polymers covalently attached to chymotrypsin. Indeed, positively charged polymers stabilized chymotrypsin to low pH, but negatively charged and amphiphilic polymers destabilized the enzyme. Lastly, after developing strategies for low pH stabilization, new protein-polymer conjugates with the chemical permeation enhancer 1-phenylpiperazine were designed to enable protein transport across the intestinal epithelium. Bovine serum albumin-poly(oligoethylene methacrylate)-block-poly(phenylpiperazine acrylamide) BSA-pOEGMA-b-pPPZ conjugates induced dose dependent increases in Caco-2 monolayer permeability and transported across an in vitro intestinal monolayer model with low cell toxicity.

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APA (6^th Edition):

Cummings, C. S. (2016). High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/692

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

Chicago Manual of Style (16^th Edition):

Cummings, Chad S. “High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/692.

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

MLA Handbook (7^th Edition):

Cummings, Chad S. “High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering.” 2016. Web. 26 Feb 2021.

Vancouver:

Cummings CS. High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/692.

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

Council of Science Editors:

Cummings CS. High Density Polymer Modification of Proteins Using Polymer - Based Protein Engineering. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/692

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

21. Seki, Stephanie M. Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/694

► Natural gas is a growing energy source in the US for various end-uses, and its potential future as a transportation fuel has been the focus… (more)

▼ Natural gas is a growing energy source in the US for various end-uses, and its potential future as a transportation fuel has been the focus of recent policy discussions. Nationally, ethanol is blended with gasoline up to 10% for conventional vehicles, and up to 85% (E85) for use in Flexible Fuel Vehicles (FFVs). Federal mandates require increasing ethanol use in the transportation sector. Meeting the mandates could mean increasing the blend in conventional gasoline, or increasing the use of E85 in FFVs. This dissertation explores the economic, environmental and policy effects from producing ethanol from natural gas, and generally expanding access to ethanol as a transportation fuel (feedstock agnostic). Three processes are considered for producing ethanol from natural gas: (1) autothermal reforming (ATR) with catalytic conversion, (2) TCX, a process that produces intermediate products of methanol and acetic acid, developed by Celanese Corp., and (3) a fermentation process developed by Coskata Inc. I first estimate the cost of producing ethanol from natural gas to power light-duty FFVs in Pennsylvania (PA). Relying on production cost estimates provided by developers and assuming recent natural gas and gasoline prices are good proxies for future prices, I conclude that the cost of producing ethanol with either the Coskata or ATR processes would more likely than not be cheaper than gasoline and corn-based ethanol. However, capital costs from these emerging processes and future natural gas and gasoline prices are highly uncertain. The NGLF ethanol must also have acceptable greenhouse gas (GHG) emissions, for which an estimate is not currently available in the literature. I find the average life cycle GHG emissions for a 100-yr global warming potential (GWP) are 137 g CO2-eqiuv/MJ (ATR Catalytic), 119 g CO2-eqiuv/MJ (Celanese TCX) and 156 g CO2-eqiuv/MJ (Coskata fermentation), given the uncertainty in some parameters the estimate could be slightly higher or lower. All processes have life cycle emissions well above gasoline, and the 20% reduction from gasoline required by the Renewable Fuel Standard (RFS2). Even in the unlikely scenario of zero emissions from the upstream processes, NGLF ethanol process and combustion emissions are still larger than gasoline, although with more overlap in the error bars. More detailed life cycle assessments with process modeling could refine the emissions estimates. Existing policies incentivize ethanol produced from renewable sources, but no current policy provisions specifically incentivize the use or production of ethanol produced from natural gas. I conclude the dissertation with estimates of additional refueling costs for an FFV driver and infrastructure costs for expanding E85 access in Pennsylvania. The state recently received government grants for biofuels infrastructure. I find that even with a subsidy to cover average infrastructure costs of 0.03 to 1.48 per gasoline gallon equivalent (gge) for the retailer, the consumer would still incur additional costs for refueling more…

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APA (6^th Edition):

Seki, S. M. (2016). Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/694

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

Chicago Manual of Style (16^th Edition):

Seki, Stephanie M. “Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/694.

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

MLA Handbook (7^th Edition):

Seki, Stephanie M. “Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania.” 2016. Web. 26 Feb 2021.

Vancouver:

Seki SM. Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/694.

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

Council of Science Editors:

Seki SM. Evaluating the Economic, Environmental and Policy Impacts of Ethanol as a Transportation Fuel in Pennsylvania. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/694

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

22. Humberson, Jonathan D. The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/699

► Sigma 3 grain boundaries play a large role in the microstructure of fcc materials in general, and particularly so in grain boundary engineered materials. A… (more)

Subjects/Keywords: antithermal motion; grain boundaries; grain boundary faceting; grain boundary motion; molecular dynamics

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APA (6^th Edition):

Humberson, J. D. (2016). The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/699

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

Chicago Manual of Style (16^th Edition):

Humberson, Jonathan D. “The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/699.

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

MLA Handbook (7^th Edition):

Humberson, Jonathan D. “The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries.” 2016. Web. 26 Feb 2021.

Vancouver:

Humberson JD. The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/699.

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

Council of Science Editors:

Humberson JD. The Motion Mechanism and Thermal Behavior of Sigma 3 Grain Boundaries. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/699

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

23. Khairi, Ahmad B. Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/700

► With the emergence of multi-standard and cognitive radios, the need for reconfigurable RF circuits increased. Such circuits require wide-band quadrature voltage controlled oscillators (QVCOs) to… (more)

Subjects/Keywords: Active quadrature coupling; CMOS; Passive quadrature coupling; Phase change switches; Quadrature voltage controlled oscillator (QVCO); Wide band

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APA (6^th Edition):

Khairi, A. B. (2016). Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/700

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

Chicago Manual of Style (16^th Edition):

Khairi, Ahmad B. “Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/700.

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

MLA Handbook (7^th Edition):

Khairi, Ahmad B. “Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches.” 2016. Web. 26 Feb 2021.

Vancouver:

Khairi AB. Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/700.

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

Council of Science Editors:

Khairi AB. Wide-Band Multi-Mode Voltage Tuning Oscillators utilizing Phase-Change Switches. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/700

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

24. Lamy, Julian V. Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/703

► Increasing the percentage of wind power in the United States electricity generation mix would facilitate the transition towards a more sustainable, low-pollution, and environmentally-conscious electricity… (more)

▼ Increasing the percentage of wind power in the United States electricity generation mix would facilitate the transition towards a more sustainable, low-pollution, and environmentally-conscious electricity grid. However, this effort is not without cost. Wind power generation is time-variable and typically not synchronized with electricity demand (i.e., load). In addition, the highest-output wind resources are often located in remote locations, necessitating transmission investment between generation sites and load. Furthermore, negative public perceptions of wind projects could prevent widespread wind development, especially for projects close to densely-populated communities. The work presented in my dissertation seeks to understand where it’s best to locate wind energy projects while considering these various factors. First, in Chapter 2, I examine whether energy storage technologies, such as grid-scale batteries, could help reduce the transmission upgrade costs incurred when siting wind projects in distant locations. For a case study of a hypothetical 200 MW wind project in North Dakota that delivers power to Illinois, I present an optimization model that estimates the optimal size of transmission and energy storage capacity that yields the lowest average cost of generation and transmission (/MWh). I find that for this application of storage to be economical, energy storage costs would have to be 100/kWh or lower, which is well below current costs for available technologies. I conclude that there are likely better ways to use energy storage than for accessing distant wind projects. Following from this work, in Chapter 3, I present an optimization model to estimate the economics of accessing high quality wind resources in remote areas to comply with renewable energy policy targets. I include temporal aspects of wind power (variability costs and correlation to market prices) as well as total wind power produced from different farms. I assess the goal of providing 40 TWh of new wind generation in the Midwestern transmission system (MISO) while minimizing system costs. Results show that building wind farms in North/South Dakota (windiest states) compared to Illinois (less windy, but close to population centers) would only be economical if the incremental transmission costs to access them were below 360/kW of wind capacity (break-even value). Historically, the incremental transmission costs for wind development in North/South Dakota compared to in Illinois are about twice this value. However, the break-even incremental transmission cost for wind farms in Minnesota/Iowa (also windy states) is 250/kW, which is consistent with historical costs. I conclude that for the case in MISO, building wind projects in more distant locations (i.e., Minnesota/Iowa) is most economical. My two final chapters use semi-structured interviews (Chapter 4) and conjoint-based surveys (Chapter 5) to understand public perceptions and preferences for different wind project siting characteristics such as the distance between the project and a…

Subjects/Keywords: Conjoint-based survey; Decision-making under uncertainty; Project development; Public preferences; Transmission; Wind Energy

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APA (6^th Edition):

Lamy, J. V. (2016). Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/703

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

Chicago Manual of Style (16^th Edition):

Lamy, Julian V. “Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/703.

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

MLA Handbook (7^th Edition):

Lamy, Julian V. “Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences.” 2016. Web. 26 Feb 2021.

Vancouver:

Lamy JV. Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/703.

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

Council of Science Editors:

Lamy JV. Optimal Locations for Siting Wind Energy Projects: Technical Challenges, Economics, and Public Preferences. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/703

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

25. Lee, Bongjoon. Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/705

► Block copolymers have attracted interests for potential application ranging from dynamic photonic sensors to solid-state ion conductors. However, due to nucleation and growth mechanism, block… (more)

Subjects/Keywords: Block copolymer; grain coarsening; grain map; kinetics; Microstructure; neutron scattering

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APA (6^th Edition):

Lee, B. (2016). Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/705

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

Chicago Manual of Style (16^th Edition):

Lee, Bongjoon. “Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/705.

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

MLA Handbook (7^th Edition):

Lee, Bongjoon. “Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure.” 2016. Web. 26 Feb 2021.

Vancouver:

Lee B. Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/705.

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

Council of Science Editors:

Lee B. Analysis of the Kinetics of Filler Segregation in Granular Block copolymer Microstructure. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/705

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

26. Li, Hai. Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/706

► As cloud computing and massive-data machine learning are applied pervasively, ultra-high volume data storage serves as the foundation block. Every day, nearly 2.5 quintillion bytes… (more)

▼ As cloud computing and massive-data machine learning are applied pervasively, ultra-high volume data storage serves as the foundation block. Every day, nearly 2.5 quintillion bytes (50000 GB/second in 2018) of data is created and stored. Hard Disk Drive (HDD) takes major part of this heavy duty. However, despite the amazing evolution of HDD technology during the past 50 years, the conventional Perpendicular Magnetic Recording (PMR), the state-of-the-art HDD technique, starts to have less momentum in increasing storage density because of the recording trilemma. To overcome this, Heat-Assisted Magnetic Recording (HAMR) was initially proposed in 1990s. With years of advancement, recent industrial demos have shown the potential of HAMR to actually break the theoretical limit of PMR. However, to fully take advantage of HAMR and realize the commercialization, there are still quite a few technical challenges, which motivated this thesis work. Via thermal coupled micromagnetic simulation based upon Landau-Lifshitz-Bloch (LLB) equation, the entire dynamic recording process has been studied systematically. The very fundamental recording physics theorem is established, which manages to elegantly interpret the previously conflicting experimental observations. The thermal induced field dependence of performance, due to incomplete switching and erase-after-write, is proposed for the first time and validated in industrial lab. The combinational effects form the ultimate physical limit of this technology. Meanwhile, this theorem predicts the novel noise origins, examples being Curie temperature distribution and temperature distribution, which are the key properties but ignored previously. To enhance performance, utilizations of higher thermal gradient, magnetically stiffer medium, optimal field etc. have been suggested based upon the theorem. Furthermore, a novel concept, Recording Time Window (RTW), has been proposed. It tightly correlates with performance and serves as a unified optimization standard, summarizing almost all primary parameters. After being validated via spin stand testing, the theorem has been applied to provide solutions for guiding medium design and relaxing the field and heating requirement. This helps solve the issues around writer limit and thermal reliability. Additionally, crosstrack varying field has been proposed to solve the well-known transition curvature issue, which may increase the storage density by 50%.

Subjects/Keywords: Data storage; HAMR; HDD; LLB; Magnetic recording; Micromagnetics

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APA (6^th Edition):

Li, H. (2016). Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/706

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

Chicago Manual of Style (16^th Edition):

Li, Hai. “Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/706.

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

MLA Handbook (7^th Edition):

Li, Hai. “Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording.” 2016. Web. 26 Feb 2021.

Vancouver:

Li H. Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/706.

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

Council of Science Editors:

Li H. Storage Physics and Noise Mechanism in Heat-Assisted Magnetic Recording. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/706

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

27. Mandal, Pratiti. Investigation and Mitigation of Degradation in Hydrogen Fuel Cells.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/709

► The ever increasing demand of petroleum in the transport sector has led to depletion of low cost/low risk reserves, increased levels of pollution, and greenhouse… (more)

▼ The ever increasing demand of petroleum in the transport sector has led to depletion of low cost/low risk reserves, increased levels of pollution, and greenhouse gas emissions that take a heavy toll on the environment as well as the national economy. There is an urgent need to use alternative energy resources along with an efficient and affordable energy conversion system to arrest environmental degradation. Polymer electrolyte fuel cells (PEFCs) show great promise in this regard - they use hydrogen gas as a fuel that electrochemically reacts with air to produce electrical energy and water as the by product. In a fuel cell electric vehicle (FCEV), these zero tail pipe emission systems offer high efficiency and power density for medium-heavy duty and long range transportation. However, PEFC technology is currently challenged by its limited durability when subjected to harsh and adverse operating conditions and transients that arises during the normal course of vehicle operation. The hydrogen-based fuel cell power train for electric vehicles must achieve high durability while maintaining high power efficiency and fuel economy in order to equal the range and lifetime of an internal-combustion-engine vehicle. The technology also needs to meet the cost targets to make FCEVs a commercial success. In this dissertation, one of the degradation phenomena that severely impede the durability of the system has been investigated. In scenarios where the cell becomes locally starved of hydrogen fuel, “cell reversal” occurs, which causes the cell to consume itself through carbon corrosion and eventually fail. Carbon corrosion in the anode disrupts the original structure of the electrode and can cause undesirable outcomes like catalyst particle migration, aggregation, loss of structural and chemical integrity. A comprehensive study using advanced electrochemical diagnostics and high resolution 3D imaging was performed and a new understanding to extend PEFC life time and robustness, by implementing engineered materials solutions, has been achieved. This will eventually help in making fuel cell systems more efficient, durable and economically viable, in order to better harness clean energy resources.

Subjects/Keywords: Electrochemical energy; Electrolysis; Failure analysis; Fuel cell; Morphology; Tomography

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

APA (6^th Edition):

Mandal, P. (2016). Investigation and Mitigation of Degradation in Hydrogen Fuel Cells. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/709

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

Chicago Manual of Style (16^th Edition):

Mandal, Pratiti. “Investigation and Mitigation of Degradation in Hydrogen Fuel Cells.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/709.

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

MLA Handbook (7^th Edition):

Mandal, Pratiti. “Investigation and Mitigation of Degradation in Hydrogen Fuel Cells.” 2016. Web. 26 Feb 2021.

Vancouver:

Mandal P. Investigation and Mitigation of Degradation in Hydrogen Fuel Cells. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/709.

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

Council of Science Editors:

Mandal P. Investigation and Mitigation of Degradation in Hydrogen Fuel Cells. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/709

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

28. Rajan, Rahul. Considerate Systems.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/713

► Recent technological advances have witnessed the rapid encroachment of computing systems into our social spaces. Their acceptance in these social spaces by other occupants, however,… (more)

▼ Recent technological advances have witnessed the rapid encroachment of computing systems into our social spaces. Their acceptance in these social spaces by other occupants, however, might be mostly contingent on their social appropriateness. Notions of social appropriateness might seem vague but even people who don’t act on this commonsense knowledge, and accord to social norms, can sometimes find themselves ostracized from society. It is reflected in behavior that supports a sense of successful engagement and connection. Such behavior communicates a desire to be accepted and a willingness to engage, as opposed to inappropriateness that conveys indifference, rejection or even danger. As social actors, how can systems improve their interactions with us in order to better succeed at their tasks? Perhaps, more interestingly, how might they even improve our communications with each other? In this thesis we describe a framework to identify opportunities to design systems that can begin to act appropriately in social settings, which we call Considerate Systems. It includes a design process and guidelines, which allows an interaction to be viewed from the perspectives of the user, system and task. It also includes an architecture that guides the addition of productive social responses to interactive systems. We demonstrate the utility of this framework by exploring two types of scenarios that impact social interactions in contrasting ways. Remote interactions (such as on a conference call) suffer from an impinging of social cues that people rely on while communicating. On the other hand, situated multitasking interactions (such as texting while driving) can easily overwhelm users and detract from their performance. The framework is applied towards the design of autonomous agents tackling problems endemic to such scenarios. We evaluate their success with respect to specific scenario goals. We conclude by noting that while the challenges of instilling computing systems with a sense of appropriateness seem daunting, our productive use of systems can be enhanced with them.

Subjects/Keywords: Cognitive load estimation; Computer-mediated communication; Context-aware computing; Socially Intelligent Agents; Speech-based feedback

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

APA (6^th Edition):

Rajan, R. (2016). Considerate Systems. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/713

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

Chicago Manual of Style (16^th Edition):

Rajan, Rahul. “Considerate Systems.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/713.

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

MLA Handbook (7^th Edition):

Rajan, Rahul. “Considerate Systems.” 2016. Web. 26 Feb 2021.

Vancouver:

Rajan R. Considerate Systems. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/713.

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

Council of Science Editors:

Rajan R. Considerate Systems. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/713

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

29. Tan, Jiaqi. Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/715

► Embedded software today is pervasive: they can be found everywhere, from coffee makers and medical devices, to cars and aircraft. Embedded software today is also… (more)

▼ Embedded software today is pervasive: they can be found everywhere, from coffee makers and medical devices, to cars and aircraft. Embedded software today is also open and connected to the Internet, exposing them to external attacks that can cause its Control-Flow Integrity (CFI) to be violated. Control-Flow Integrity is an important safety property of software, which ensures that the behavior of the software is not inadvertently changed. The violation of CFI in software can cause unintended behaviors, and can even lead to catastrophic incidents in safety-critical systems. This dissertation develops a two-part approach for CFI: (i) prescribing source-code safetychecks, that prevent the root-causes of CFI, that programmers can insert themselves, and (ii) formally proving CFI for the machine-code of programs with source-code safety-checks. First, our prescribed safety-checks, when applied, prevent the root-causes of CFI, thereby enabling software to recover from CFI violations in a customizable way. In addition, our prescribed safety-checks are visible to programmers, empowering them to ensure that the behavior of their software is not inadvertently changed by the prescribed safety-checks. However, programmer-inserted safety-checks may be incomplete. Thus, current techniques for proving CFI, which assume that safety-checks are complete, may not work. Second, this dissertation develops a logic approach that automates formal proofs of CFI for the machine-code of software containing both source-code CFI safety-checks and system calls. We extend an existing trustworthy Hoare logic with new proof rules, proof tactics, and a novel proof-search algorithm, which exploit the principle of local reasoning for safety properties to automatically generate CFI proofs for the machine-code of programs compiled with our prescribed source-code safety-checks. To the best of our knowledge, our approach to CFI is the first to combine programmer-visible source-code enforcement mechanisms for CFI–enabling programmers to customize them and observe that their software is not inadvertently changed–with machine-code proofs of CFI that can be automated, and that does not require a trusted or verified compiler to ensure its proven properties hold in machine-code. We evaluate our CFI approach on realistic embedded software. We evaluate our approach on the MiBench and WCET benchmarks, implementations of common file utilities, and programs interfacing with hardware inputs and outputs on the Raspberry Pi single-board-computer. The variety of our target programs, and our ability to support useful features such as file and hardware inputs and outputs, demonstrate the wide applicability of our approach.

Subjects/Keywords: Computer Security; Control Flow Integrity; Formal Methods; Hoare Logic; Software Verification; Theorem Proving

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

APA (6^th Edition):

Tan, J. (2016). Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/715

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

Chicago Manual of Style (16^th Edition):

Tan, Jiaqi. “Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/715.

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

MLA Handbook (7^th Edition):

Tan, Jiaqi. “Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity.” 2016. Web. 26 Feb 2021.

Vancouver:

Tan J. Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/715.

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

Council of Science Editors:

Tan J. Prescriptive Safety-Checks through Automated Proofs for Control-Flow Integrity. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/715

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

30. Wong, You Liang Lionel. Piezoelectric Ribbons for Stretchable Energy Harvesting.

Degree: 2016, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/718

► As we enter the age of the internet of things (IoT), more embedded devices are appearing in our everyday items, such as electrical appliances, watches,… (more)

▼ As we enter the age of the internet of things (IoT), more embedded devices are appearing in our everyday items, such as electrical appliances, watches, mobile phones, and even clothes. These are devices that are able to communicate with one another and collect sensing data about their environment. An emerging area of interest in this field is the wearable devices, such as smart devices for healthcare and wellness implantables. These devices require power and batteries will need to be constantly recharged, adding to the users’ inconvenience. Energy harvesters are devices that are able to harness ambient energy such as movement and convert it into useful electrical energy. As such, energy harvesters are expected to play an important role in powering such devices in order to save space and more importantly to increase the comfort and convenience of the users. This work presents a piezoelectric energy harvester that captures energy from stretchable surfaces such as the human skin, exterior of organs and even garments. The main feature of the harvester is the inclusion of a ribbon structure encased in a flexible elastomer, Ecoflex. This allows the device to stretch to tens of percents, while maintaining strain levels of the piezoelectric material within its mechanical limits, which is required since stretchable surfaces can strain to tens of percent. This device provides an efficient method of converting overall device stretch to bending stress within the piezoelectric material, and can strain both horizontally and vertically. Polyvinylidene fluoride (PVDF) and its copolymer, polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) are the material of choice due to their flexibility and magnitude of piezoelectric coefficients. A thickness of 10-28 μm is chosen for the PVDF film and the total device thickness including the Ecoflex ranges from 1-3 mm. Bimorph structure and alternately-connected electrodes ensure that charge cancellation is minimized. Static and transient finite element modeling are carried out to characterize the devices and obtain trends for design parameters. The trends obtained will allow the user to select device parameters given certain constraints such as film thickness and device effective Young’s modulus. Two fabrication approaches are used to fabricate planar PVDF, PVDF-TrFE films. The first approach involves fabricating the film starting from PVDF-TrFE powder. The powder is dissolved in a solvent and cast using an in-house stainless steel structure onto a wafer that has spincast gelatin. Gelatin acts as a release layer. Aluminum and chromium are sputtered and patterned on the wafer before a second layer of PVDF-TrFE is cast again. A top metal is then patterned and a method to etch the PVDF-TrFE is developed in order to access the bottom metal. Each PVDF-TrFE layer is 10 μm thick. To ensure that the electrodes are flexible, mesh designs are incorporated. Various measurements such as mechanical, ferroelectric and piezoresponse measurements are carried out to verify the performance of the film. The…

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

APA (6^th Edition):

Wong, Y. L. L. (2016). Piezoelectric Ribbons for Stretchable Energy Harvesting. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/718

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

Chicago Manual of Style (16^th Edition):

Wong, You Liang Lionel. “Piezoelectric Ribbons for Stretchable Energy Harvesting.” 2016. Thesis, Carnegie Mellon University. Accessed February 26, 2021. http://repository.cmu.edu/dissertations/718.

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

MLA Handbook (7^th Edition):

Wong, You Liang Lionel. “Piezoelectric Ribbons for Stretchable Energy Harvesting.” 2016. Web. 26 Feb 2021.

Vancouver:

Wong YLL. Piezoelectric Ribbons for Stretchable Energy Harvesting. [Internet] [Thesis]. Carnegie Mellon University; 2016. [cited 2021 Feb 26]. Available from: http://repository.cmu.edu/dissertations/718.

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

Council of Science Editors:

Wong YLL. Piezoelectric Ribbons for Stretchable Energy Harvesting. [Thesis]. Carnegie Mellon University; 2016. Available from: http://repository.cmu.edu/dissertations/718

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

Open Access Theses and Dissertations