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Stem Academic Engagement In Young Children With Autism: A Single Case Design Study, Yixuan Ji Jan 2018

Stem Academic Engagement In Young Children With Autism: A Single Case Design Study, Yixuan Ji

Electronic Theses and Dissertations

The researcher examined the academic engagement in Circle Time activities and STEM (science, technology, engineering, and mathematics) activities for three young children with autism spectrum disorders (ASD) who attended a large Orange County Public School, enrolled in an ASD preschool classroom. Given the increasing number of children diagnosed with ASD each year and many STEM job opportunities for individuals with ASD, it is becoming important to know how young children with ASD learn and engage in STEM activities. Strengths of individuals with ASD in the STEM field have been reported in several research studies (Chen & Weko, 2009; Kirchner, Ruch …

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Quality Indicators For Classrooms Serving Students With Autism Spectrum Disorder: A Construct Validation Study, Rebecca Hopkins Jan 2018

Quality Indicators For Classrooms Serving Students With Autism Spectrum Disorder: A Construct Validation Study, Rebecca Hopkins

Electronic Theses and Dissertations

A rise in the prevalence of students with ASD points to the need for more qualified and effective teachers to meet the needs of this population. Existing research delineates evidence-based practices and teaching standards positively improve educational outcomes for students with ASD. Teacher evaluation systems have the potential to highlight strengths and areas for improvement in special education teaching practices. Research on observation instruments to evaluate the unique skills and knowledge of special education teachers of students with ASD is limited. A need exists for high quality observation instruments to measure teacher performance in special education classrooms serving students with …

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An Examination Of Movement Between Preschool And Kindergarten Classrooms For Young Children With Developmental Disabilities, Faith Ezekiel-Wilder Jan 2018

An Examination Of Movement Between Preschool And Kindergarten Classrooms For Young Children With Developmental Disabilities, Faith Ezekiel-Wilder

Electronic Theses and Dissertations

The researcher in this investigation describes the similarities and differences of movement in preschool and kindergarten classrooms for young children with developmental delay. Through the use of a mixed method research design, the researcher examined how movement is integrated throughout a school day and integrated into teacher-directed mathematics activities. This study used a multiple case study method that included observations of preschool (n = 3) and kindergarten (n = 3) classrooms to determine similarities and differences in movement. In addition, a quantitative measure was embedded within the multiple case study design to compare movement of children with developmental delay. A …

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Non-Hermitian Optics, Absar Ulhassan Jan 2018

Non-Hermitian Optics, Absar Ulhassan

Electronic Theses and Dissertations

From the viewpoint of quantum mechanics, a system must always be Hermitian since all its corresponding eigenvalues must be real. In contrast, the eigenvalues of open systems-unrestrained because of either decay or amplification-can be in general complex. Not so long ago, a certain class of non-Hermitian Hamiltonians was discovered that could have a completely real eigenvalue spectrum. This special class of Hamiltonians was found to respect the property of commutation with the parity-time (PT) operator. Translated into optics, this implies a balance between regions exhibiting gain and loss. Traditionally, loss has been perceived as a foe in optics and something …

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A Value Sensitive Design Approach To Adolescent Mobile Online Safety, Arup Kumar Ghosh Jan 2018

A Value Sensitive Design Approach To Adolescent Mobile Online Safety, Arup Kumar Ghosh

Electronic Theses and Dissertations

With the rise of adolescent smartphone use, concerns about teen online safety are also on the rise. A number of parental control apps are available for mobile devices, but adoption of these apps has been markedly low. To better understand these apps, their users, and design opportunities in the space of mobile online safety for adolescents, we have conducted four studies informed by the principles of Value Sensitive Design (VSD). In Study 1 (Chapter 2), we conducted a web-based survey of 215 parents and their teens (ages 13-17) using two separate logistic regression models (parent and teen) to examine the …

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Transformative Learning: Improving Teachers' Cultural Competencies Through Knowledge And Practice Of Ubuntu Pedagogy, Alecia Blackwood Jan 2018

Transformative Learning: Improving Teachers' Cultural Competencies Through Knowledge And Practice Of Ubuntu Pedagogy, Alecia Blackwood

Electronic Theses and Dissertations

The pursuit of this ethnographic study was inspired by my lived experiences as an urban school teacher for 18 years, as well as, the experiences of a group of other urban teachers. The study explored the following question: Does knowledge and practice of Ubuntu pedagogy help to improve teachers' cultural competencies in an urban school? The research documents how knowledge and practice of the three pillars of Ubuntu pedagogy help to transform the perspective of urban teachers. The three pillars are (1) Humanism and Ubuntu Competency, (2) Collaboration and Partnership, and (3) Relationship and Learning Community. Data were collected using …

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Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland Jan 2018

Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland

Electronic Theses and Dissertations

Intraspecific phenotype diversity allows for local adaption and the ability for species to respond to changing environmental conditions, enhancing survivability. Phenotypic variation could be stochastic, genetically based, and/or the result of different environmental conditions. Mojave Rattlesnakes, Crotalus scutulatus, are known to have high intraspecific venom variation, but the geographic extent of the variation and factors influencing venom evolution are poorly understood. Three primary venom types have been described in this species based on the presence (Type A) or absence (Type B) of a neurotoxic phospholipase A2 called Mojave toxin and an inverse relationship with the presence of snake venom metalloproteinases …

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Power Scaling Of High Power Solid State Lasers., Bumjin Oh Jan 2018

Power Scaling Of High Power Solid State Lasers., Bumjin Oh

Electronic Theses and Dissertations

The solid-state laser is one of the most widely used lasers in scientific research and industrial applications. This thesis describes detailed investigations of two modern architectures of high power cw solid-state lasers, a 20 W diode-pumped Yb:YAG thin disc laser and 300 W diode-pumped Nd:YAG rod laser. With the thin disc laser architecture, the signal beam must fit to the pump area on the disc defined by the multi-pass diode pump configuration. The beam propagation, beam diameter, phase and thermal effects for various cavity configurations are investigated theoretically and experimentally. In addition, the internal loss, small signal gain, and thermal …

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Experimental Confirmation Of Ballistic Nanofriction And Quasiparticle Interference In Dirac Materials., Michael Lodge Jan 2018

Experimental Confirmation Of Ballistic Nanofriction And Quasiparticle Interference In Dirac Materials., Michael Lodge

Electronic Theses and Dissertations

This dissertation is broadly divided into two parts. The first part details the development and usage of an experimental apparatus to measure the dry nanofriction for a well-defined interface at high sliding speeds. I leverage the sensitivity of a quartz crystal microbalance (QCM) to determine the drag coefficient of an ensemble of gold nanocrystals sliding on graphene at speeds up to 11 cm/s. I discuss the theories of velocity-dependent friction, especially at high sliding speeds, and QCM modeling. I also discuss our synthesis protocols for graphene and molybdenum disulfide, as well as our protocol for fabricating a clean, graphene-laminated QCM …

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Regolith-Based Construction Materials For Lunar And Martian Colonies, Kevin Grossman Jan 2018

Regolith-Based Construction Materials For Lunar And Martian Colonies, Kevin Grossman

Electronic Theses and Dissertations

Humankind's ambitions of exploring our solar system and parts beyond depend heavily on our ability to collect resources from local environments at our destinations rather than bringing materials on the journey. This is a concept known as in-situ resource utilization (ISRU) and it is one that has been understood by every explorer and settler in the history of humankind. Regolith on the moon and Mars has been shown to be a particularly useful resource and has the ability to provide humans with resources including water, oxygen, construction material, fabric, radiation shielding, metals, and may more. This dissertation focuses on construction …

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Development Of A Tabletop Coherent Soft X-Ray Source, Hanfu Kong Jan 2018

Development Of A Tabletop Coherent Soft X-Ray Source, Hanfu Kong

Electronic Theses and Dissertations

The goal of this thesis is to design a tabletop coherent soft X-ray source for attosecond high resolution imaging. We collect signals from gas cells with different length and lens with different focal length. A spectrometer with a grating and a CCD camera is applied to observe and measure the spectrum of the X-ray attosecond pulses. This thesis first introduces the theory background of ultrafast lasers, then mainly explains high harmonic generation, which is the key method for attosecond pulses generation, subsequently presents the experiment system and analyzes the results from the experiment, also compares different combinations of parameters of …

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Middle Grades Science In Florida: A Comparison Of Student Achievement In Comprehensive And Subject-Specific Science Courses 2013-2017, Kenneth Moore Jan 2018

Middle Grades Science In Florida: A Comparison Of Student Achievement In Comprehensive And Subject-Specific Science Courses 2013-2017, Kenneth Moore

Electronic Theses and Dissertations

As with U.S. student achievement on national and international science assessments, Florida's 8th grade student achievement on the 2013–2017 8th grade Florida Comprehensive Assessment Test (FCAT) 2.0 Science/Statewide Science Assessment (SSA) was stagnant. To break this stagnation, many Florida school districts have changed middle grades science course offerings from traditional, subject-specific, discipline-based, layered, or field-specific science courses to comprehensive, integrated, spiraled, interdisciplinary, multidisciplinary, thematic, or general science courses. There was a lack of research showing if either type of science course improved student achievement on standardized science assessments. Controlling for school district student population, low socio-economic status (SES) student percentage, …

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Making An Impression: A Formal Analysis Of The Contextual And Iconographic Characteristics Of Ancient Mexican Ceramic Stamps, Elizabeth Rose Lyon Peabody Jan 2018

Making An Impression: A Formal Analysis Of The Contextual And Iconographic Characteristics Of Ancient Mexican Ceramic Stamps, Elizabeth Rose Lyon Peabody

Electronic Theses and Dissertations

Ceramic stamps are a rare, yet widely distributed, artifact class within ancient Mexico. However, there has only been limited scholarly research on these objects and much current research is minimally supported. Depicting a wide range of iconography, including metaphysical, floral, and faunal designs, the function and meaning of these stamps, also known as estampias, pintaderas, and sellos, in ancient Mexican life remain an archaeological mystery. This paper examines the contextual, chronological, and iconographic characteristics of ancient Mexican ceramic stamps as well as the distributional trends of those characteristics. This study is comprised of 83 stamps of varying design that date …

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In Situ Treatment Systems For Remediation Of Polychlorinated Biphenyl-Contaminated Building Materials, Adibah Almutairi Jan 2018

In Situ Treatment Systems For Remediation Of Polychlorinated Biphenyl-Contaminated Building Materials, Adibah Almutairi

Electronic Theses and Dissertations

Polychlorinated Biphenyls (PCBs) are a family of synthetic organohalides comprising 209 congeners which were used historically as additives in paint and caulking materials over a span of many years. Even though the production of PCBs in the USA has been banned since the late 1970s, their former prevalence and widespread use means many structures are still coated with PCB-laden paints. In addition, the presence of PCBs in elastic sealants has resulted in transport of PCBs into concrete structures and has caused soil contamination around buildings. PCB-contaminated building materials have become a significant concern for the environment and building occupants due …

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Light Scattering Property Of Gold Nanoparticles With Applications To Biomolecule Detection And Analysis, Tianyu Zheng Jan 2018

Light Scattering Property Of Gold Nanoparticles With Applications To Biomolecule Detection And Analysis, Tianyu Zheng

Electronic Theses and Dissertations

Gold nanoparticles (AuNPs) have unique optical and chemical properties. Dynamic light scattering (DLS) is an analytical tool used routinely for nanoparticle size measurement. The combined use of AuNPs and DLS has led to a novel analytical assay technology called D2Dx (from diameter to diagnostics). Herein, my dissertation highlights the extended use of D2Dx for biomolecule detection and analysis. Under this general theme, Chapter 1 provides some background information of AuNPs, DLS, the principle of D2Dx technique and its potential applications. Chapter 2 summarizes a study on the effect of AuNP concentrations and laser power on the hydrodynamic size measurement of …

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Terahertz Emission From The Intrinsic Josephson Junctions Of High-Symmetry Thermally-Managed Bi2sr2cacu2o8+D Annular Microstrip Antennas, Sheila Bonnough Jan 2018

Terahertz Emission From The Intrinsic Josephson Junctions Of High-Symmetry Thermally-Managed Bi2sr2cacu2o8+D Annular Microstrip Antennas, Sheila Bonnough

Electronic Theses and Dissertations

The intrinsic Josephson junctions in the high transition temperature superconductor Bi2Sr2CaCu2O8+δ (BSCCO) have shown great potential for oscillators emitting in the terahertz frequency. The radiation frequency satisfies the conditions for both the ac Josephson effect and for a mesa cavity resonance mode. The observed angular dependence of the emissions from some mesa imply that the ac Josephson effect plays the primary role in a dual source radiation mechanism. But the integrated emission power had generally been significantly below the 1 mW level suitable for many applications. This output power can be enhanced by a suitable design of an array of …

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A Phenomenological Study Of Black Fifth Grade Students' Perceptions Of Social Studies And A Discussion With Secondary Students, Irenea Walker Jan 2018

A Phenomenological Study Of Black Fifth Grade Students' Perceptions Of Social Studies And A Discussion With Secondary Students, Irenea Walker

Electronic Theses and Dissertations

The problem I address in this study is the lack of Black elementary students' knowledge and interest of the social studies content. Black students who lack a true identity of self, fail to develop into productive citizens. Although previous studies have examined Black students' experiences in secondary social studies classrooms, few have thoroughly examined Black students' experiences in the elementary classrooms. For this study, I analyze Black fifth grade students' perceptions of the social studies content. Identifying these perceptions is imperative so educators can adjust their pedagogical practices based on what they deem as important for educational growth, and the …

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Liquid Crystal Phase Modulation For Beam Steering And Near-Eye Displays, Yun-Han Lee Jan 2018

Liquid Crystal Phase Modulation For Beam Steering And Near-Eye Displays, Yun-Han Lee

Electronic Theses and Dissertations

Liquid crystal spatial phase modulator plays an important role in laser beam steering, wave-front shaping and correction, optical communication, optical computation and holography. One fundamental limitation lays in the response time of liquid crystal reorientation. To achieve fast response time, polymer-network liquid crystals are therefore proposed. By incorporating polymer network in a liquid crystal host, the response time can be reduced by a factor of 100. However, the polymer network introduces hysteresis, light scattering, and high voltage. The motivation for a fast-response liquid crystal phase modulator will be discussed in the first chapter. In the second chapter, we introduce our …

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Sampling And Subspace Methods For Learning Sparse Group Structures In Computer Vision, Maryam Jaberi Jan 2018

Sampling And Subspace Methods For Learning Sparse Group Structures In Computer Vision, Maryam Jaberi

Electronic Theses and Dissertations

The unprecedented growth of data in volume and dimension has led to an increased number of computationally-demanding and data-driven decision-making methods in many disciplines, such as computer vision, genomics, finance, etc. Research on big data aims to understand and describe trends in massive volumes of high-dimensional data. High volume and dimension are the determining factors in both computational and time complexity of algorithms. The challenge grows when the data are formed of the union of group-structures of different dimensions embedded in a high-dimensional ambient space. To address the problem of high volume, we propose a sampling method referred to as …

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Energy Efficient And Secure Wireless Sensor Networks Design, Afraa Attiah Jan 2018

Energy Efficient And Secure Wireless Sensor Networks Design, Afraa Attiah

Electronic Theses and Dissertations

Wireless Sensor Networks (WSNs) are emerging technologies that have the ability to sense, process, communicate, and transmit information to a destination, and they are expected to have significant impact on the efficiency of many applications in various fields. The resource constraint such as limited battery power, is the greatest challenge in WSNs design as it affects the lifetime and performance of the network. An energy efficient, secure, and trustworthy system is vital when a WSN involves highly sensitive information. Thus, it is critical to design mechanisms that are energy efficient and secure while at the same time maintaining the desired …

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Fluid Dynamics Modeling And Sound Analysis Of A Bileaflet Mechanical Heart Valve, Fardin Khalili Jan 2018

Fluid Dynamics Modeling And Sound Analysis Of A Bileaflet Mechanical Heart Valve, Fardin Khalili

Electronic Theses and Dissertations

Cardiovascular disease (CVD) is one of the main causes of death in the world. Some CVD involve severe heart valve disease that require valve replacement. There are more than 300,000 heart valves implanted worldwide, and about 85,000 heart valve replacements in the US. Approximately half of these valves are mechanical. Artificial valves may dysfunction leading to adverse hemodynamic conditions. Understanding the normal and abnormal valve function is important as it help improve valve designs. Modeling of heart valve hemodynamics using computational fluid dynamics (CFD) provides a comprehensive analysis of flow, which can potentially help explain clinical observations and support therapeutic …

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Biomechanical Models Of Human Upper And Tracheal Airway Functionality, Don Nadun Kuruppumullage Jan 2018

Biomechanical Models Of Human Upper And Tracheal Airway Functionality, Don Nadun Kuruppumullage

Electronic Theses and Dissertations

The respiratory tract, in other words, the airway, is the primary airflow path for several physiological activities such as coughing, breathing, and sneezing. Diseases can impact airway functionality through various means including cancer of the head and neck, Neurological disorders such as Parkinson's disease, and sleep disorders and all of which are considered in this study. In this dissertation, numerical modeling techniques were used to simulate three distinct airway diseases: a weak cough leading to aspiration, upper airway patency in obstructive sleep apnea, and tongue cancer in swallow disorders. The work described in this dissertation, therefore, divided into three biomechanical …

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Characterization Of Fast Flames For Turbulence-Induced Deflagration To Detonation Transition, Jessica Chambers Jan 2018

Characterization Of Fast Flames For Turbulence-Induced Deflagration To Detonation Transition, Jessica Chambers

Electronic Theses and Dissertations

One of the fundamental mechanisms for detonation initiation is turbulence driven deflagration to detonation transition (TDDT). The research experimentally explores the propagation dynamics demonstrated by fast deflagrated flames interacting with highly turbulent reactants. Fast flames produce extremely high turbulent flame speeds values, increased levels of compressibility and develop a runaway mechanism that leads to TDDT. The flame structural dynamics and reacting flow field are characterized using simultaneous high-speed particle image velocimetry, chemiluminescence, and Schlieren measurements. The investigation classifies the fast flame propagation modes at various regimes. The study further examines the conditions for a turbulent fast flame at the boundary …

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Compiler Design Of A Policy Specification Language For Conditional Gradual Release, Manasa Kashyap Harinath Jan 2018

Compiler Design Of A Policy Specification Language For Conditional Gradual Release, Manasa Kashyap Harinath

Electronic Theses and Dissertations

Securing the confidentiality and integrity of information manipulated by computer software is an old yet increasingly important problem. Current software permission systems present on Android or iOS provide inadequate support for developing applications with secure information flow policies. To be useful, information flow control policies need to specify declassifications and the conditions under which declassification must occur. Having these declassifications scattered all over the program makes policies hard to find, which makes auditing difficult. To overcome these challenges, a policy specification language, 'Evidently' is discussed that allows one to specify information flow control policies separately from the program and which …

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Practical Dynamic Transactional Data Structures, Pierre Laborde Jan 2018

Practical Dynamic Transactional Data Structures, Pierre Laborde

Electronic Theses and Dissertations

Multicore programming presents the challenge of synchronizing multiple threads. Traditionally, mutual exclusion locks are used to limit access to a shared resource to a single thread at a time. Whether this lock is applied to an entire data structure, or only a single element, the pitfalls of lock-based programming persist. Deadlock, livelock, starvation, and priority inversion are some of the hazards of lock-based programming that can be avoided by using non-blocking techniques. Non-blocking data structures allow scalable and thread-safe access to shared data by guaranteeing, at least, system-wide progress. In this work, we present the first wait-free hash map which …

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Learning Algorithms For Fat Quantification And Tumor Characterization, Sarfaraz Hussein Jan 2018

Learning Algorithms For Fat Quantification And Tumor Characterization, Sarfaraz Hussein

Electronic Theses and Dissertations

Obesity is one of the most prevalent health conditions. About 30% of the world's and over 70% of the United States' adult populations are either overweight or obese, causing an increased risk for cardiovascular diseases, diabetes, and certain types of cancer. Among all cancers, lung cancer is the leading cause of death, whereas pancreatic cancer has the poorest prognosis among all major cancers. Early diagnosis of these cancers can save lives. This dissertation contributes towards the development of computer-aided diagnosis tools in order to aid clinicians in establishing the quantitative relationship between obesity and cancers. With respect to obesity and …

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Relating First-Person And Third-Person Vision, Shervin Ardeshir Behrostaghi Jan 2018

Relating First-Person And Third-Person Vision, Shervin Ardeshir Behrostaghi

Electronic Theses and Dissertations

Thanks to the availability and increasing popularity of wearable devices such as GoPro cameras, smart phones and glasses, we have access to a plethora of videos captured from the first person (egocentric) perspective. Capturing the world from the perspective of one's self, egocentric videos bear characteristics distinct from the more traditional third-person (exocentric) videos. In many computer vision tasks (e.g. identification, action recognition, face recognition, pose estimation, etc.), the human actors are the main focus. Hence, detecting, localizing, and recognizing the human actor is often incorporated as a vital component. In an egocentric video however, the person behind the camera …

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A Methodology On Weapon Combat Effectiveness Analytics Using Big Data And Live, Virtual, Or/And Constructive Simulations, Won Jung Ii Jan 2018

A Methodology On Weapon Combat Effectiveness Analytics Using Big Data And Live, Virtual, Or/And Constructive Simulations, Won Jung Ii

Electronic Theses and Dissertations

The Weapon Combat Effectiveness (WCE) analytics is very expensive, time-consuming, and dangerous in the real world because we have to create data from the real operations with a lot of people and weapons in the actual environment. The Modeling and Simulation (M&S) of many techniques is used for overcoming these limitations. Although the era of big data has emerged and achieved a great deal of success in a variety of fields, most WCE research using the Defense Modeling and Simulation (DM&S) techniques were studied without the help of big data technologies and techniques. The existing research has not considered various …

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Real-Time Sil Emulation Architecture For Cooperative Automated Vehicles, Nitish Gupta Jan 2018

Real-Time Sil Emulation Architecture For Cooperative Automated Vehicles, Nitish Gupta

Electronic Theses and Dissertations

This thesis presents a robust, flexible and real-time architecture for Software-in-the-Loop (SIL) testing of connected vehicle safety applications. Emerging connected and automated vehicles (CAV) use sensing, communication and computing technologies in the design of a host of new safety applications. Testing and verification of these applications is a major concern for the automotive industry. The CAV safety applications work by sharing their state and movement information over wireless communication links. Vehicular communication has fueled the development of various Cooperative Vehicle Safety (CVS) applications. Development of safety applications for CAV requires testing in many different scenarios. However, the recreation of test …

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A Study On The Plasticity And Fracture Of Aisi 4340 Steel Under Different Loading Conditions Considering Heat Treatment And Micromechanics, Sami Ghazali Jan 2018

A Study On The Plasticity And Fracture Of Aisi 4340 Steel Under Different Loading Conditions Considering Heat Treatment And Micromechanics, Sami Ghazali

Electronic Theses and Dissertations

Accurate predictions of material strength under different loading conditions with large plastic deformation and ductile fracture are of great importance. This dissertation aims to develop an essential understanding of ductile fracture of AISI 4340 steel alloy using both empirical and micromechanics based models. For this purpose, 29 specimens of different geometries with different heat-treatments were designed to investigate the effects of stress states. These specimens are: (a) 13 round bars with different notches (axial symmetric tension); (b) 13 flat grooved specimens with different grooves; (c) 3 small round cylinders. Mechanical tests up to fracture were conducted on these specimens to …

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