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2019

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Full-Text Articles in Engineering

Campaign Structure Distillation For Methyl Palmitate Separation From Palm Oil Biodiesel Using Vacuum Batch Distillation, Supakorn Songpanit Jan 2019

Campaign Structure Distillation For Methyl Palmitate Separation From Palm Oil Biodiesel Using Vacuum Batch Distillation, Supakorn Songpanit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, the competition of palm oil biodiesel production in Thailand will increase essentially in the sector for the next few years. Therefore, this study aims to find a new approach for converting palm oil biodiesel or fatty acid methyl ester mixture, into a specialty chemical to increase the value of palm oil biodiesel. Campaign structure distillation was considered to design a separation process using vacuum batch distillation, and turn only one batch process into the sequence of methyl ester cut as a continuous process. The objective is to study the effect of operating parameters on campaign structure distillation for methyl …


Effects Of Pyridine-Based Electron Donors On Ziegler-Natta Catalyst Performance In Ethylene/1-Hexene Copolymerization, Natchayapak Phiromphu Jan 2019

Effects Of Pyridine-Based Electron Donors On Ziegler-Natta Catalyst Performance In Ethylene/1-Hexene Copolymerization, Natchayapak Phiromphu

Chulalongkorn University Theses and Dissertations (Chula ETD)

Linear low-density polyethylene (LLDPE) is a type of polymer that has been used in a wide range of applications because of its attractive mechanical properties. The mainly synthetic polyolefins are produced by supported Ziegler-Natta catalysts (ZN). The major components to modify ZN catalyst contain active Ti species precursor, aluminum alkyl cocatalyst, MgCl2 support and electron donor. The MgCl2-supported titanium catalysts have the multiple types of active centers. Thus, the copolymers having broad molecular weight distribution (MWD) and chemical composition distribution (CCD). However, the drawback of ZN catalyst is its very low comonomer insertion. In this research, the author would like …


การลดก๊าซเรือนกระจกจากการอนุรักษ์พลังงานและการจัดการขยะมูลฝอยของสถานศึกษา, นิภาพร เดโชเกียรติถวัลย์ Jan 2019

การลดก๊าซเรือนกระจกจากการอนุรักษ์พลังงานและการจัดการขยะมูลฝอยของสถานศึกษา, นิภาพร เดโชเกียรติถวัลย์

Chulalongkorn University Theses and Dissertations (Chula ETD)

สถานศึกษาเป็นหน่วยงานขนาดใหญ่ที่ประกอบไปด้วยกิจกรรมที่มีความหลากหลาย จึงถือเป็นองค์กรที่สำคัญแห่งหนึ่งซึ่งมีการใช้พลังงานสูงทั้งในรูปพลังงานไฟฟ้าและเชื้อเพลิง นอกจากนี้ยังก่อให้เกิดขยะปริมาณมาก ซึ่งหมายถึงเป็นแหล่งของการปล่อยก๊าซเรือนกระจกสูงด้วย งานวิจัยนี้ได้ทำการประเมินคาร์บอนฟุตพริ้นท์องค์กรของสถานศึกษาพร้อมทั้งศึกษาแนวทางการลดการปล่อยก๊าซเรือนกระจกจากการอนุรักษ์พลังงงานและการจัดการขยะมูลฝอย ผลการศึกษาพบว่า ในปีพ.ศ. 2561 มหาวิทยาลัย ก มหาวิทยาลัย ข และวิทยาลัย ค มีปริมาณการปล่อยก๊าซเรือนกระจกทั้งหมดเท่ากับ 5,912.32 6,487.32 และ 1,458.05 ตันคาร์บอนไดออกไซด์เทียบเท่าต่อปี ตามลำดับ โดยการใช้พลังงานไฟฟ้าในขอบเขตที่ 2 และการกำจัดขยะในขอบเขตที่ 3 เป็นกิจกรรมที่ส่งผลต่อการปล่อยก๊าซเรือนกระจกมากที่สุดเป็นอันดับ 1 และ 2 ตามลำดับ มาตรการอนุรักษ์พลังงานซึ่งมีศักยภาพในการลดก๊าซเรือนกระจกและมีความคุ้มค่าทางเศรษฐศาสตร์ ได้แก่ มาตรการการเปลี่ยนไปใช้เครื่องปรับอากาศและเครื่องทำน้ำเย็นประสิทธิภาพสูง การติดตั้งอุปกรณ์ควบคุมความเร็วรอบเครื่องสูบน้ำเย็น การเปลี่ยนไปใช้หลอดไฟแบบ LED และการติดตั้ง Solar rooftop บนอาคาร นอกจากนี้การจัดการขยะมูลฝอยซึ่งมีประสิทธิภาพในการลดก๊าซเรือนกระจก สามารถทำได้โดยการจัดการขยะแบบผสมผสาน ได้แก่ การฝังกลบร่วมกับการคัดแยกขยะเพื่อการรีไซเคิล การนำเศษอาหารไปเป็นอาหารสัตว์ และการนำใบไม้มาทำสารปรับปรุงดิน


การวางแผนการจัดหาเหล็กแผ่นโดยพิจารณาร่วมกับการใช้ประโยชน์เศษเหล็กในการผลิตชิ้นส่วนรถบรรทุก, กฤติยา อึ่งวรากร Jan 2019

การวางแผนการจัดหาเหล็กแผ่นโดยพิจารณาร่วมกับการใช้ประโยชน์เศษเหล็กในการผลิตชิ้นส่วนรถบรรทุก, กฤติยา อึ่งวรากร

Chulalongkorn University Theses and Dissertations (Chula ETD)

เนื่องจากการผลิตรถบรรทุกของโรงงานกรณีศึกษามีกระบวนการตัดเหล็กม้วนโดยใช้การปั๊มขึ้นรูปกรอบประตูรถบรรทุก ซึ่งทำให้เกิดเศษเหล็กเหลือใช้เป็นจำนวนมาก โรงงานจึงมีแนวคิดในการสร้างมูลค่าเพิ่มให้แก่เศษเหล็ก โดยการใช้เศษเหล็กเป็นวัตถุดิบในการผลิตชิ้นส่วนรถบรรทุกจำนวน 7 รายการชิ้นส่วน เพื่อลดต้นทุนวัตถุดิบในการผลิต งานวิจัยนี้มีวัตถุประสงค์เพื่อนำเสนอวิธีการวางแผนการจัดหาเหล็กแผ่นโดยพิจารณาร่วมกับการใช้ประโยชน์เศษเหล็กในการผลิตชิ้นส่วนรถบรรทุกโดยการประยุกต์ใช้การวัดความแม่นยำของข้อมูลด้วยวิธี MAD ในการลดทอนความคลาดเคลื่อนของการพยากรณ์ความต้องการชิ้นส่วนรถบรรทุกที่มีการปรับเปลี่ยนไปจนกว่าจะถึงกำหนดการส่งมอบ การศึกษาต้นทุนที่เกิดจากกิจกรรมในกระบวนการตัดเหล็กเพื่อกำหนดเกณฑ์การตัดสินใจ การใช้โปรแกรมเชิงเส้นในการจัดสรรเศษเหล็กให้แก่ชิ้นส่วนรถบรรทุกต่าง ๆ สำหรับใช้เป็นวัตถุดิบเพื่อให้เกิดการลดต้นทุนการผลิตชิ้นส่วนสูงสุด การประมาณค่าความเบี่ยงเบนของค่าสัมบูรณ์ของความคลาดเคลื่อนเพื่อกำหนดพัสดุคงคลัง และการประยุกต์ใช้แบบจำลองระดับคงคลังเป้าหมาย เพื่อหาจำนวนเหล็กแผ่นที่จะต้องจัดหาจากผู้ขายตามระยะเวลาที่กำหนด เมื่อดำเนินทดสอบด้วยข้อมูลจริงตั้งแต่ ก.ย.2561 – เม.ย.2562 พบว่าโรงงานลดต้นทุนในการจัดหาเหล็กแผ่นลงได้ 19% คิดเป็นมูลค่า 866, 452 บาท นอกจากการจัดสรรเศษเหล็กเพื่อนำมาใช้เป็นวัตถุดิบแล้วนั้นยังสามารถลดความคลาดเคลื่อนของข้อมูลความต้องการชิ้นส่วนรถบรรทุก 5 % และการปรับปรุงวิธีการคำนวณจำนวนเหล็กแผ่นเพื่อใช้เป็นพัสดุคงคลังลดลงได้ 65 % โดยยังคงตอบสนองต่อลูกค้าที่ระดับให้บริการที่ 95%


Connecting The Pieces: How Low Back Pain Alters Lower Extremity Biomechanics And Shock Attenuation In Active Individuals, Alexa Johnson Jan 2019

Connecting The Pieces: How Low Back Pain Alters Lower Extremity Biomechanics And Shock Attenuation In Active Individuals, Alexa Johnson

Theses and Dissertations--Rehabilitation Sciences

Low back pain in collegiate athletes has been reported at a rate of 37% from a wide array of sports including soccer, volleyball, football, swimming, and baseball. Whereas, in a military population the prevalence of low back pain is 70% higher than the general population. Compensatory movement strategies are often used as an attempt to reduce pain. Though compensatory movement strategies may effectively reduce pain, they are often associated with altered lower extremity loading patterns. Those who suffer from chronic low back pain tend to walk and run slower and with less trunk and pelvis coordination and variability. Individuals with …


Parametric Study Of A Turbofan Engine With An Auxiliary High-Pressure Bypass, Sharanabasaweshwara A. Asundi, Syed Firasat Ali Jan 2019

Parametric Study Of A Turbofan Engine With An Auxiliary High-Pressure Bypass, Sharanabasaweshwara A. Asundi, Syed Firasat Ali

Mechanical & Aerospace Engineering Faculty Publications

A parametric study of a novel turbofan engine with an auxiliary high-pressure bypass (AHPB) is presented. The underlying motivation for the study was to introduce and explore a configuration of a turbofan engine which could facilitate clean secondary burning of fuel at a higher temperature than conventionally realized. The study was also motivated by the developments in engineering materials for high-temperature applications and the potential utility of these developments. The parametric study is presented in two phases. Phase I presents a schematic of the turbofan engine with AHPB and the mathematics of the performance parameters at various stations. The proposed …


Development Of A Switchable Radioisotope Generator, Kyle Mitchell Paaren Jan 2019

Development Of A Switchable Radioisotope Generator, Kyle Mitchell Paaren

Doctoral Dissertations

The Switchable Radioisotope Generator utilizes alpha-induced reactions to produce a combination of photons, neutrons, and protons with varying fluxes dependent on target materials and source geometry. The activity/strength of the secondary radiation is further controlled by manipulating the number of alpha particles that can interact with the target material(s). Analytical equations were solved to confirm secondary radiation production from target materials using average cross sections from TENDL data. TENDL and JENDL data was confirmed by analytically solving for the total alpha-induced cross sections. This information was used to produce the provisional and utility Patent No: US20190013109A1. TENDL data was then …


Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah Jan 2019

Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

The properties of a material are defined by its granular microstructure which is determined by its grain evolution and the types of grain boundaries present in the structure. For example, the performance of Cadmium Sulfide/Cadmium Telluride (CdS/CdTe) solar cells can be affected by the presence of grain boundaries which makes the study of grain structure evolution a very important part of solar cell performance optimization. Grain boundary mobilities are important properties in material science and engineering as they determine grain structures under given processing and operating conditions.

In this thesis, several computational tools were used to analyze the formation and …


Towards Multiple Model Approach To Bridge Deterioration, Jin A. Collins Jan 2019

Towards Multiple Model Approach To Bridge Deterioration, Jin A. Collins

Open Access Theses & Dissertations

The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) marked the start of a new era in transportation in the United States. ISTEA required transportation agencies to take a proactive approach to planning and management of their assets. This included requirements for managing pavement, bridges, safety, congestion, public transportation, and intermodal systems. For horizontal transportation assets (i.e., bridges and pavement), deterioration modeling is an essential tool (Yanev and Chen 1993). Since ISTEA, Bridge Management Systems (BMS) have been utilized to inform decision-making regarding bridge projects such as maintenance, rehabilitation, and replacement (MR&R) under financial limitations (Agrawal, Kawaguchi, and Chen 2010). …


Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia Jan 2019

Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia

Open Access Theses & Dissertations

Steel industry is a major emitter of air pollutants, a leading industrial consumer of water, a minor source of contaminated liquids, a massive producer of solid waste, and a significant source of CO2. The objective on this thesis work is to minimize the greenhouse gas emissions when processing steel. Gears and bearings were evaluated based on their performance when exposed to cyclic stresses. The importance for having a proper set up on rolling mills to increase efficiency for processing rebar steel has been detailed on paper. In contrast, mechanical vibration has been measured on gears and bearings to determine efficiency …


Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete Jan 2019

Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete

Open Access Theses & Dissertations

Unprecedented levels of production and consumption have caused a rapid exhaustion of the Earth's virgin resources, which is coupled with a fast accumulation of contaminants in the form of solid waste, especially in landfills. Two significant landfill constituents come from textile waste and discarded plastic bottles. Since there is a finite amount of space that can be feasibly used for landfills, solutions that make use of these post-consumer products are imperative. This study presents one possible solution by using surface modifications of cotton fibers to produce a natural fiber-reinforced polymer composite (NFRPC) from post-consumer textile waste and polyethylene terephthalate (PET) …


Interference Mitigation Of Adjacent Radio Frequency Signals On A Flexible Software-Defined Radio Testbed Platform, Mirza Mohammad Maqbule Maqbule Elahi Jan 2019

Interference Mitigation Of Adjacent Radio Frequency Signals On A Flexible Software-Defined Radio Testbed Platform, Mirza Mohammad Maqbule Maqbule Elahi

Open Access Theses & Dissertations

The radio frequency (RF) spectrum is crowded with users and adjacent frequency users are facing an increase in interference from each other. The spectrum governing body Federal Communications Commission (FCC) has the difficult task of allocating spectral bands for new users for mobile devices using 4G LTE technology. Telemetry is affected by the adjacent band 4G LTE users in terms of signal degradation. To minimize the interference between adjacent frequency users, several methods can be used. A common but inefficient method separates adjacent band frequencies using guard bands which leaves a big portion of the spectrum unused. Alternatively, adjacent RF …


Impact Of Temperature And Screw Speed On Material Meso-Structure And Tensile Strength In Large Area Pellet-Fed Additive Manufacturing, Xavier Jimenez Guzman Jan 2019

Impact Of Temperature And Screw Speed On Material Meso-Structure And Tensile Strength In Large Area Pellet-Fed Additive Manufacturing, Xavier Jimenez Guzman

Open Access Theses & Dissertations

Evolution in additive manufacturing, specifically in material extrusion, has resulted in large-scale machines capable of extruding thermoplastic-matrix composite materials in higher volumes to fabricate products for large-scale applications. As with small- and medium-scale material extrusion, the properties of the final product often correlate directly with the bevy of print parameters employed. The current research was performed to evaluate the effects of the screw speed and temperature on an ABS 20%wt. carbon fiber thermoplastic processed on a Big Area Additive Manufacturing (BAAM, Cincinnati Inc) machine. Five screw speeds (50, 150, 250, 350 and 400 rpm) and three extruder temperature profiles were …


Small Satellite Development At Utep, Emily Herzog Jan 2019

Small Satellite Development At Utep, Emily Herzog

Open Access Theses & Dissertations

The small satellite industry has seen tremendous growth in recent years. A CubeSat is a particular type of standardized small satellite that follows the CubeSat specifications. These specifications define the structural, testing, and operational requirements of the satellite. This standard facilitates cheaper design, integration, and launch of satellites, allowing smaller organizations to participate in the normally costly area of space exploration.

The University of Texas at El Paso has recognized the opportunity and has begun developing several CubeSats. The two that are the topic of this Thesis are called Orbital Factory II (OFII) and Orbital Factory X (OFX). An on-orbit …


An Alternative Method Of Calibration And Prediction For The Theta-Projection Model, Jimmy Jesus Perez Jan 2019

An Alternative Method Of Calibration And Prediction For The Theta-Projection Model, Jimmy Jesus Perez

Open Access Theses & Dissertations

The combustion induced high temperature-stress conditions of industrial gas turbines used in power generation causes turbine blades to wear and break after prolonged use. The need to predict turbine blade service life is ever increasing, leading to the development of several constitutive prediction models. It is necessary to design components for high-temperature/high-stress service such that creep failure does not occur during service life. For this reason, it is important to accurately predict creep life and understand the behavior of creep deformation leading to rupture. Several models have been expanded upon to improve their effectiveness for use with particular parametric data. …


Synthesis, Characterization And Antibacterial Properties Of Silver(I) N-(4-Pyridyl) Benzamide Complexes With Varying Conterions, Mauro J. Ruiz Jan 2019

Synthesis, Characterization And Antibacterial Properties Of Silver(I) N-(4-Pyridyl) Benzamide Complexes With Varying Conterions, Mauro J. Ruiz

Open Access Theses & Dissertations

Organic semiconductor materials composed of - stacking aromatic compounds have been under intense investigation for their potential uses in flexible electronics and other advanced technologies. Herein we report a new family of seven - stacking compounds of Silver(I) N-(4-pyridyl) Benzamide with varying counterions, namely [Ag(NPBA)2]X, where NPBA is N-(4-pyridyl) Benzamine, X = NO3- (1), ClO4- (2), CF3SO3- (3), PF6- (4), BF4- (5), CH3PhSO3- (6), and PhSO3- (7), which form extended - stacking networks in one-dimensional (1D), 2D and 3D directions in the crystalline solid-state via the phenyl moiety, with average inter-ring distances of 3.823 Å. Interestingly, the counterions that contain …


Adaptive Microphone Array Systems With Neural Network Applications, Jazmine Marisol Covarrubias Jan 2019

Adaptive Microphone Array Systems With Neural Network Applications, Jazmine Marisol Covarrubias

Open Access Theses & Dissertations

A microphone array integrated with a neural network framework is proposed to enhance and optimize speech signals derived from environments prone to noise and room reflections that cause reverberation. Microphone arrays provide a way to capture spatial acoustic information for extracting voice input from ambient noise. In this study, we utilize and analyze established signal processing methods combined with different neural network architectures to achieve denoised and dereverberated speech signal results that are comparable with their clean, anechoic versions. The first stage of the proposed system involves using datasets containing anechoic speech recordings of speech utterances and convolving them with …


Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan Jan 2019

Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan

Open Access Theses & Dissertations

With the development of distributed energy resources (DERs) and advancements in technology, microgrids (MGs) appear primed to become an even more integral part of the future distribution grid. In this transition to the smart power grid of the future, MGs must be properly managed and controlled to allow efficient integration of DERs. Over the past years, there has been rapid adoption of roof-top solar photovoltaic (PV) and battery electric vehicles (BEVs). Although roof-top solar PV and BEVs can provide environmental benefits (e.g., reduction of emissions), they also create various challenges for power system operators. For example, roof-top solar PV generation …


Decision Support Tools For Parking Management On University Campuses, Okan Gurbuz Jan 2019

Decision Support Tools For Parking Management On University Campuses, Okan Gurbuz

Open Access Theses & Dissertations

University campuses generate and attract trips with unique characteristics. Most universities are constantly challenged by the parking congestion issues. To manage campus parking infrastructure, most universities have established parking departments. This department is referred as the University Parking Office (UPO) in this Dissertation. There is no methodology or tool to assist the UPOs in their decision-making process. This Dissertation focuses on student parking and has developed models and methodologies as decision support tools to assist UPOs in managing student parking on campuses.

This Dissertation answers six Research Questions related to parking management on university campuses: (1) How many students are …


System Dynamic Model Of 1-Dimensional Unsaturated Water And Solute Transport For Predicting Salinity Stress In Crops, Thomas Poulose Jan 2019

System Dynamic Model Of 1-Dimensional Unsaturated Water And Solute Transport For Predicting Salinity Stress In Crops, Thomas Poulose

Open Access Theses & Dissertations

There is a complex non-linear system dynamic between the water and salt transport in the unsaturated vadose zone where the salt transport and accumulation affect the water fluxes and vice versa. In addition, factors such as precipitation, transpiration, water infiltration and solute transport in the unsaturated zone of subsurface soil further complicate the processes involved. We have developed a system dynamics model for simulating the one-dimensional unsaturated water and solute transport along with root water uptake in the vadose zone. The model uses finite difference method for solving Richard's equation with a sink term for water transport and root water …


Tailoring Physical Properties Of Shape Memory Polymers For Fdm-Type Additive Manufacturing, Paulina Aileen Quinonez Jan 2019

Tailoring Physical Properties Of Shape Memory Polymers For Fdm-Type Additive Manufacturing, Paulina Aileen Quinonez

Open Access Theses & Dissertations

Shape memory polymers (SMPs) have found applicability in biomedical settings as well as other uses that can take advantage of objects that can change shape upon exposure to stimulus. Integrating polymers with shape memory characteristics into additive manufacturing technologies such as fused deposition modeling (FDMâ?¢) can increase the number of applications this manufacturing platform can be utilized. Currently, polyurethane and polylactic acid (PLA) are two FDMâ?¢-compatible materials that possess shape memory properties. On their own these materials do not have tunable shape memory properties, namely shape recovery and shape fixation. The work presented here entails the development and characterization of …


Artificial Intelligence In The Assessment Of Transmission And Distribution Systems Under Natural Disasters Using Machine Learning And Deep Learning Techniques In A Knowledge Discovery Framework, Rossana Villegas Jan 2019

Artificial Intelligence In The Assessment Of Transmission And Distribution Systems Under Natural Disasters Using Machine Learning And Deep Learning Techniques In A Knowledge Discovery Framework, Rossana Villegas

Open Access Theses & Dissertations

Warming trends and increasing temperatures have been observed and reported by federal agencies, such as the National Oceanic and Atmospheric Administration (NOAA). Extreme-weather events, especially hurricanes, tornadoes and winter storms, are among the highly devastating natural disasters responsible for massive and prolonged power outages in Electrical Transmission and Distribution Systems (ETDS). Moreover, the failure rate probability of any system component under extreme-weather tends to increase in the impacted geographic area. This Dissertation proposes an Artificial Intelligence (AI) Decision Support System that can predict damage in the ETDS and allow operators to mitigate disastrous extreme weather events. The document reports the …


Towards Analytical Techniques For Systems Engineering Applications, Griselda Valdepeñas Acosta Jan 2019

Towards Analytical Techniques For Systems Engineering Applications, Griselda Valdepeñas Acosta

Open Access Theses & Dissertations

One of the main objectives of systems engineering is to design, maintain, and analyze systems that help the users. To design an appropriate system for an application domain, we need to know: what are the users' desires and preferences (so that we know in what direction we should aim to change this domain), what is the current state and what is the dynamics of this application domain, and how to use all this information to select the best alternatives for the system design and maintenance. Designing a system includes selecting numerical values for many of the parameters describing the corresponding …


Designing Biomimetic Implant Surfaces To Promote Osseointegration Under Osteoporotic Conditions By Revitalizing Mechanisms Coupling Bone Resorption To Formation, Ethan M. Lotz Jan 2019

Designing Biomimetic Implant Surfaces To Promote Osseointegration Under Osteoporotic Conditions By Revitalizing Mechanisms Coupling Bone Resorption To Formation, Ethan M. Lotz

Theses and Dissertations

In cases of compromised bone remodeling like osteoporosis, insufficient osseointegration occurs and results in implant failure. Implant retention relies on proper secondary fixation, which is developed during bone remodeling. This process is disrupted in metastatic bone diseases like osteoporosis. Osteoporosis is characterized low bone mass and bone strength resulting from either accelerated osteoclast-mediated bone resorption or impaired osteoblast-mediated bone formation. These two processes are not independent phenomena. In fact, osteoporosis can be viewed as a breakdown of the cellular communication connecting bone resorption to bone formation. Because bone remodeling occurs at temporally generated specific anatomical sites and at different times, …


Overview Of Homechem: House Observations Of Microbial And Environmental Chemistry, Delphine K. Farmer, Marina E. Vance, Jon P. D. Abbatt, Andrew Abeleira, Michael R. Alves, Richard Corsi, Peter F. Decarlo, Allen H. Goldstein, Vicki H. Grassian, Lea Hildebrandt Ruiz, Jose L. Jimenez, Tara Kahan, Multiple Additional Authors Jan 2019

Overview Of Homechem: House Observations Of Microbial And Environmental Chemistry, Delphine K. Farmer, Marina E. Vance, Jon P. D. Abbatt, Andrew Abeleira, Michael R. Alves, Richard Corsi, Peter F. Decarlo, Allen H. Goldstein, Vicki H. Grassian, Lea Hildebrandt Ruiz, Jose L. Jimenez, Tara Kahan, Multiple Additional Authors

Mechanical and Materials Engineering Faculty Publications and Presentations

The House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO2, NOx, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated …


The Influence Of 3d Porous Chitosan-Alginate Biomaterial Scaffold Properties On The Behavior Of Breast Cancer Cells, Minh-Chau N. Le Jan 2019

The Influence Of 3d Porous Chitosan-Alginate Biomaterial Scaffold Properties On The Behavior Of Breast Cancer Cells, Minh-Chau N. Le

Honors Undergraduate Theses

The tumor microenvironment plays an important role in regulating cancer cell behavior. The tumor microenvironment describes the cancer cells, and the surrounding endothelial cells, fibroblasts, and mesenchymal stem cells, along with the extracellular matrix (ECM). The tumor microenvironment stiffens as cancer undergoes malignant progression, providing biophysical cues that promote invasive, metastatic cellular behaviors. This project investigated the influence of three dimensional (3D) chitosan-alginate (CA) scaffold stiffness on the morphology, growth, and migration of green fluorescent protein (GFP) – transfected MDA-MB-231 (231-GFP) breast cancer (BCa) cells. The CA scaffolds were produced by the freeze casting method at three concentrations, 2 wt%, …


Stochasticity In An Artificial Neuron Using Ag/2d-Mos2/Au Threshold Switching Memristor, Madison Manley Jan 2019

Stochasticity In An Artificial Neuron Using Ag/2d-Mos2/Au Threshold Switching Memristor, Madison Manley

Honors Undergraduate Theses

Neuromorphic computing comprises of systems that are based on the human brain or artificial neural networks, with the promise of creating a brain inspired ability to learn and adapt, but technical challenges, such as developing an accurate neuroscience model of the functionality of the brain to building devices to support these models, are significantly hindering the progress of neuromorphic systems. This has paved the way for artificial neural networks (ANN) to meet these criteria. The memristor has become an emerging candidate to realize ANN through emulation synapse and neuron behavior. In this work, we are fabricating an Ag/MoS­2/Au …


High Performance Liquid Crystal Devices For Augmented Reality And Virtual Reality, Md Javed Rouf Talukder Jan 2019

High Performance Liquid Crystal Devices For Augmented Reality And Virtual Reality, Md Javed Rouf Talukder

Electronic Theses and Dissertations

See-through augmented reality and virtual reality displays are emerging due to their widespread applications in education, engineering design, medical, retail, transportation, automotive, aerospace, gaming, and entertainment. For augmented reality and virtual reality displays, high-resolution density, high luminance, fast response time and high ambient contrast ratio are critically needed. High-resolution density helps eliminate the screen-door effect, high luminance and fast response time enable low duty ratio operation, which plays a key role for suppressing image blurs. A dimmer placed in front of AR display helps to control the incident background light, which in turn improves the image contrast. In this dissertation, …


Imaging Through Glass-Air Anderson Localizing Optical Fiber, Jian Zhao Jan 2019

Imaging Through Glass-Air Anderson Localizing Optical Fiber, Jian Zhao

Electronic Theses and Dissertations

The fiber-optic imaging system enables imaging deeply into hollow tissue tracts or organs of biological objects in a minimally invasive way, which are inaccessible to conventional microscopy. It is the key technology to visualize biological objects in biomedical research and clinical applications. The fiber-optic imaging system should be able to deliver a high-quality image to resolve the details of cell morphology in vivo and in real time with a miniaturized imaging unit. It also has to be insensitive to environmental perturbations, such as mechanical bending or temperature variations. Besides, both coherent and incoherent light sources should be compatible with the …


Nanoscale Spectroscopy In Energy And Catalytic Applications, Yi Ding Jan 2019

Nanoscale Spectroscopy In Energy And Catalytic Applications, Yi Ding

Electronic Theses and Dissertations

Emerging societal challenges such as the need for more sustainable energy and catalysis are requiring more sensitive and versatile measurements at the nanoscale. This is the case in the design and optimization of new materials for energy harvesting (solar cells) and energy storage devices (batteries and capacitors), or for the development of new catalysts for carbon sequestration or other reactions of interest. Hence, the ability to advance spectroscopy with nanoscale spatial resolution and high sensitivity holds great promises to meet the demands of deeper fundamental understanding to boost the development and deployment of nano-based devices for real applications. In this …