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Hydro-Thermo-Mechanical Behavior Of Concrete At Elevated Temperatures, Manar Al Fadul Jan 2017

Hydro-Thermo-Mechanical Behavior Of Concrete At Elevated Temperatures, Manar Al Fadul

Electronic Theses and Dissertations

In the light of recent tragic events, such as, natural disasters, arson and terrorism, studying the thermo mechanical behavior of concrete at elevated temperatures has become of special concern. In addition, the fact that concrete has been widely used as a structural material in many critical applications, such as high rise buildings, pressure vessels, and nuclear plants, enhances the potential risk of exposing concrete to high temperatures. Accordingly, the potential damage to large-scale structures during the course of the fire, besides the possible loss of human life, emphasizes the necessity to better understand the thermo-structural behavior and failure mechanism of …

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Implementation Of Refining Statements In Openjml And Verification Of Higher Order Methods With Model Program Specifications, Sai Chandesh Gurramkonda Jan 2017

Implementation Of Refining Statements In Openjml And Verification Of Higher Order Methods With Model Program Specifications, Sai Chandesh Gurramkonda

Electronic Theses and Dissertations

The Java Modeling Language (JML) describes the functional behavior of Java classes and methods using pre- and postconditions. However, standard pre- and postcondition specifications cannot verify calls to higher order methods (HOMs). JML uses model program specifications to reason about HOMs. This thesis describes the implementation of model programs in the OpenJML tool. The implementation includes parsing, type checking, and matching of model program specifications against the code.

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Prototype Development In General Purpose Representation And Association Machine Using Communication Theory, Huihui Li Jan 2017

Prototype Development In General Purpose Representation And Association Machine Using Communication Theory, Huihui Li

Electronic Theses and Dissertations

Biological system study has been an intense research area in neuroscience and cognitive science for decades of years. Biological human brain is created as an intelligent system that integrates various types of sensor information and processes them intelligently. Neurons, as activated brain cells help the brain to make instant and rough decisions. From the 1950s, researchers start attempting to understand the strategies the biological system employs, then eventually translate them into machine-based algorithms. Modern computers have been developed to meet our need to handle computational tasks which our brains are not capable of performing with precision and speed. While in …

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Analysis Of Pedestrian Safety Using Micro-Simulation And Driving Simulator, Jiawei Wu Jan 2017

Analysis Of Pedestrian Safety Using Micro-Simulation And Driving Simulator, Jiawei Wu

Electronic Theses and Dissertations

In recent years, traffic agencies have begun to place emphasis on the importance of pedestrian safety. In the United States, nearly 70,000 pedestrians were reported injured in 2015. Although the number only account for 3% of all the people injured in traffic crashes, the number of pedestrian fatalities is still around 15% of total traffic fatalities. Furthermore, the state of Florida has consistently ranked as one of the worst states in terms of pedestrian crashes, injuries and fatalities. Therefore, it is befitting to focus on the pedestrian safety. This dissertation mainly focused on pedestrian safety at both midblock crossings and …

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Learning Robotic Manipulation From User Demonstrations, Rouhollah Rahmatizadeh Jan 2017

Learning Robotic Manipulation From User Demonstrations, Rouhollah Rahmatizadeh

Electronic Theses and Dissertations

Personal robots that help disabled or elderly people in their activities of daily living need to be able to autonomously perform complex manipulation tasks. Traditional approaches to this problem employ task-specific controllers. However, these must to be designed by expert programmers, are focused on a single task, and will perform the task as programmed, not according to the preferences of the user. In this dissertation, we investigate methods that enable an assistive robot to learn to execute tasks as demonstrated by the user. First, we describe a learning from demonstration (LfD) method that learns assistive tasks that need to be …

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A Multiagent Q-Learning-Based Restoration Algorithm For Resilient Distribution System Operation, Jungseok Hong Jan 2017

A Multiagent Q-Learning-Based Restoration Algorithm For Resilient Distribution System Operation, Jungseok Hong

Electronic Theses and Dissertations

Natural disasters, human errors, and technical issues have caused disastrous blackouts to power systems and resulted in enormous economic losses. Moreover, distributed energy resources have been integrated into distribution systems, which bring extra uncertainty and challenges to system restoration. Therefore, the restoration of power distribution systems requires more efficient and effective methods to provide resilient operation. In the literature, using Q-learning and multiagent system (MAS) to restore power systems has the limitation in real system application, without considering power system operation constraints. In order to adapt to system condition changes quickly, a restoration algorithm using Q-learning and MAS, together with …

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Dynamic Job-Shop Scheduling Program (Djsp) Analysis For Preventive Military Helicopter Maintenance System (Pms), Kyungjin Park Jan 2017

Dynamic Job-Shop Scheduling Program (Djsp) Analysis For Preventive Military Helicopter Maintenance System (Pms), Kyungjin Park

Electronic Theses and Dissertations

Republic of Korea Army(ROKA) has been founding new attack helicopter troops since last year by adopting US main attack helicopter, AH-64E Apache, and peripheral system like pilots and mechanics training systems and their organization. The AH-64E Apache is a major attack helicopter of the US Army and all of its systems are verified in terms of the effectiveness in real operations for several decades. However, ROKA still needs their own version of systems including tactics, template, and maintenance which are suitable for Korean terrain, climate, personnel, and so on. At least ROKA needs to have a chance to verify that …

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Super Resolution Of Wavelet-Encoded Images And Videos, Vildan Atalay Jan 2017

Super Resolution Of Wavelet-Encoded Images And Videos, Vildan Atalay

Electronic Theses and Dissertations

In this dissertation, we address the multiframe super resolution reconstruction problem for wavelet-encoded images and videos. The goal of multiframe super resolution is to obtain one or more high resolution images by fusing a sequence of degraded or aliased low resolution images of the same scene. Since the low resolution images may be unaligned, a registration step is required before super resolution reconstruction. Therefore, we first explore in-band (i.e. in the wavelet-domain) image registration; then, investigate super resolution. Our motivation for analyzing the image registration and super resolution problems in the wavelet domain is the growing trend in wavelet-encoded imaging, …

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Development And Implementation Of A Streamlined Process For The Creation And Mechanization Of Negative Poisson's Ratio Meso-Scale Patterns, Matthew Shuler Jan 2017

Development And Implementation Of A Streamlined Process For The Creation And Mechanization Of Negative Poisson's Ratio Meso-Scale Patterns, Matthew Shuler

Electronic Theses and Dissertations

This thesis focuses on the development a streamlined process used to create novel meso-scale pattern used to induce negative Poisson's ratio (NPR) behavior at the bulk scale. This process includes, the development, optimization, and implementation of a candidate pattern. Currently, the majority of NPR structures are too porous to be utilized in conventional applications. For others, manufacturing methods have yet to realize the meso-scale pattern. Consequently, new NPR meta-materials must be developed in order to confer transformative thermomechanical responses to structures where transverse expansion is more desirable than contraction. For example, materials at high temperature. Additionally, patterns that take into …

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Online Neuro-Adaptive Learning For Power System Dynamic State Estimation, Rahul Birari Jan 2017

Online Neuro-Adaptive Learning For Power System Dynamic State Estimation, Rahul Birari

Electronic Theses and Dissertations

With the increased penetration of renewable generation in the smart grid , it is crucial to have knowledge of rapid changes of system states. The information of real-time electro-mechanical dynamic states of generators are essential to ensuring reliability and detecting instability of the grid. The conventional SCADA based Dynamic State Estimation (DSE) was limited by the slow sampling rates (2-4 Hz). With the advent of PMU based synchro-phasor technology in tandem with Wide Area Monitoring System (WAMS), it has become possible to avail rapid real-time measurements at the network nodes. These measurements can be exploited for better estimates of system …

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Modeling Of Flow Generated Sound In A Constricted Duct At Low Mach Number Flow, Peshala Thibbotuwawa Gamage Jan 2017

Modeling Of Flow Generated Sound In A Constricted Duct At Low Mach Number Flow, Peshala Thibbotuwawa Gamage

Electronic Theses and Dissertations

Modelling flow and acoustics in a constricted duct at low Mach numbers is important for investigating many physiological phenomena such as phonation, generation of arterial murmurs, and pulmonary conditions involving airway obstruction. The objective of this study is to validate computational fluid dynamics (CFD) and computational aero-acoustics (CAA) simulations in a constricted tube at low Mach numbers. Different turbulence models were employed to simulate the flow field. Models included Reynolds Average Navier-Stokes (RANS), Detached eddy simulation (DES) and Large eddy simulation (LES). The models were validated by comparing study results with laser doppler anemometry (LDA) velocity measurements. The comparison showed …

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Hashing For Multimedia Similarity Modeling And Large-Scale Retrieval, Kai Li Jan 2017

Hashing For Multimedia Similarity Modeling And Large-Scale Retrieval, Kai Li

Electronic Theses and Dissertations

In recent years, the amount of multimedia data such as images, texts, and videos have been growing rapidly on the Internet. Motivated by such trends, this thesis is dedicated to exploiting hashing-based solutions to reveal multimedia data correlations and support intra-media and inter-media similarity search among huge volumes of multimedia data. We start by investigating a hashing-based solution for audio-visual similarity modeling and apply it to the audio-visual sound source localization problem. We show that synchronized signals in audio and visual modalities demonstrate similar temporal changing patterns in certain feature spaces. We propose to use a permutation-based random hashing technique …

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Assessment Of Tattoo And Silicone Wounds In Terms Of Time Of Treatment And Perceived Treatment Quality, M Pettitt Jan 2017

Assessment Of Tattoo And Silicone Wounds In Terms Of Time Of Treatment And Perceived Treatment Quality, M Pettitt

Electronic Theses and Dissertations

At the point of injury, critical medical tasks include locating and identifying an injury as well as applying the appropriate initial care. Over the past decade, to increase the fidelity of wound representation and ultimately the quality of medical care, a considerable amount of research and development has occurred to improve simulated wounds during training, primarily at the point of injury. As material and techniques mature and as more relevant data is collected on tissue properties, examining what fidelity is required for training at the point of injury is crucial. The main objective of this effort was to assess a …

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Weakly Labeled Action Recognition And Detection, Waqas Sultani Jan 2017

Weakly Labeled Action Recognition And Detection, Waqas Sultani

Electronic Theses and Dissertations

Research in human action recognition strives to develop increasingly generalized methods that are robust to intra-class variability and inter-class ambiguity. Recent years have seen tremendous strides in improving recognition accuracy on ever larger and complex benchmark datasets, comprising realistic actions "in the wild" videos. Unfortunately, the all-encompassing, dense, global representations that bring about such improvements often benefit from the inherent characteristics, specific to datasets and classes, that do not necessarily reflect knowledge about the entity to be recognized. This results in specific models that perform well within datasets but generalize poorly. Furthermore, training of supervised action recognition and detection methods …

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Multi-Axial Thermomechanical Characterization Of Shape Memory Alloys For Improved Stability, Douglas Nicholson Jan 2017

Multi-Axial Thermomechanical Characterization Of Shape Memory Alloys For Improved Stability, Douglas Nicholson

Electronic Theses and Dissertations

Shape recovery in shape memory alloys (SMAs) occurs against external stress by means of a reversible thermoelastic solid state phase transformation typically between so-called austenite, martensite and R-phases. The ability to do work enables their use as high-force actuators in automotive and aerospace applications while superelastic NiTi is of interest in biomedical devices such as stents. Both R-phase and martensite can detwin, reorient and undergo a thermal or stress induced transformation. For these reasons, it is difficult from ordinary macroscopic measurements to decouple elastic and inelastic contributions (from their respective phases) from the overall deformation. In situ neutron diffraction is …

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Faculty Professional Development For Improving Hybrid Course Success, Jennifer Lawhon Jan 2017

Faculty Professional Development For Improving Hybrid Course Success, Jennifer Lawhon

Electronic Theses and Dissertations

The purpose of this Dissertation in Practice was to investigate the inconsistent success rates in hybrid courses at a Florida college. Results from a pilot study and faculty survey revealed a need for a training program specific to hybrid instructors. The researchers created a training program composed of a framework and a professional development course, designed to promote consistency in how instructors create and implement their hybrid courses. The framework consists of six research-based standards which aided in the creation of six learning modules for the professional development course. These modules were: course alignment, face-to-face active learning, online resources, formative …

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Bridging The Gap Between Esol And Native English Speakers In A Digital Collaborative Classroom, Shalander Samuels Jan 2017

Bridging The Gap Between Esol And Native English Speakers In A Digital Collaborative Classroom, Shalander Samuels

Electronic Theses and Dissertations

The purpose of this dissertation in practice was to explore how to bridge the gap between ESOL students and native English speaking students in a collaborative learning environment in a middle school in Tangerine Florida. The gap in performance was highlighted because ESOL students failed to meet the same levels of academic achievement (based on the Florida Standard Assessment Test) as their native English-speaking counter parts. The intent of the dissertation was to design a framework that would meet the pedagogical needs of ESOL students and teachers who teach them. A pilot study was completed that included teachers both ESOL-endorsed …

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The Relationship Between Participation In Tutoring And Accountability Outcomes In Three Urban Middle Schools, Pamela Rajadhyax Jan 2017

The Relationship Between Participation In Tutoring And Accountability Outcomes In Three Urban Middle Schools, Pamela Rajadhyax

Electronic Theses and Dissertations

This quantitative study was conducted to determine the relationship between participation in a school based tutoring and change in accountability measures on the Florida Standards Assessment (FSA) in Mathematics and English Language Arts (ELA) in the 2014-2015 and 2015-2016 school years. The research was designed to determine the impact of participation in tutoring for urban middle school students. All students who attended one of the three urban middle schools and participated in the administration of FSA for mathematics or ELA in both the 2014-2015 and 2015-2016 school years were divided into two groups: students who participated in school based tutoring …

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Reducing The Overhead Of Memory Space, Network Communication And Disk I/O For Analytic Frameworks In Big Data Ecosystem, Xuhong Zhang Jan 2017

Reducing The Overhead Of Memory Space, Network Communication And Disk I/O For Analytic Frameworks In Big Data Ecosystem, Xuhong Zhang

Electronic Theses and Dissertations

To facilitate big data processing, many distributed analytic frameworks and storage systems such as Apache Hadoop, Apache Hama, Apache Spark and Hadoop Distributed File System (HDFS) have been developed. Currently, many researchers are conducting research to either make them more scalable or enabling them to support more analysis applications. In my PhD study, I conducted three main works in this topic, which are minimizing the communication delay in Apache Hama, minimizing the memory space and computational overhead in HDFS and minimizing the disk I/O overhead for approximation applications in Hadoop ecosystem. Specifically, In Apache Hama, communication delay makes up a …

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The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2017, Buenaventura "Ven" Basco Jan 2017

The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2017, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.

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Measuring And Modeling Nmr And Emission Spectra To Gain New Insight Into Challenging Organic Compounds, Jacob Powell Jan 2017

Measuring And Modeling Nmr And Emission Spectra To Gain New Insight Into Challenging Organic Compounds, Jacob Powell

Electronic Theses and Dissertations

The advancement of theoretical methods in recent years has allowed the calculation of highly accurate spectroscopic parameters. Comparing these values to the corresponding experimental data can allow molecular structures to be elucidated. This dissertation details the use of experimental and theoretical data from nuclear magnetic resonance (NMR) and fluorescence spectroscopy to determine structure. Herein the NMR focus is on measuring & modeling chemical shift anisotropy and one-bond carbon-carbon J-coupling constants (1JCC). The fluorescence analysis models vibrationally resolved fluorescence spectra. Chemical shift anisotropy techniques were used to study two conflicting crystal structures of the n-alkyl fatty acid, lauric acid. These two …

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Time-Resolved Phosphorescence Spectroscopy At Cryogenic Temperatures For The Environmental Analysis Of Polycyclic Aromatic Sulfur Heterocycles In Oil Contaminated Sites., Maha Al-Tameemi Jan 2017

Time-Resolved Phosphorescence Spectroscopy At Cryogenic Temperatures For The Environmental Analysis Of Polycyclic Aromatic Sulfur Heterocycles In Oil Contaminated Sites., Maha Al-Tameemi

Electronic Theses and Dissertations

The large volume of crude oil released into the Gulf of Mexico by the Deepwater Horizon (DWH) accident has raised considerable concerns over potential ecosystem impacts. The dispersion of harmful oil components into the ocean waters could pose long term risks to flora and fauna. Due to the complexity of oil contaminated sites, the unambiguous identification and quantitation of environmental pollutants often requires the sequence of high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). A classic example is the analysis of the sixteen polycyclic aromatic hydrocarbons included in the priority pollutants list of the U.S. Environmental Protection Agency (EPA-PAHs). …

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Thermal And Waveguide Optimization Of Broad Area Quantum Cascade Laser Performance, Matthew Suttinger Jan 2017

Thermal And Waveguide Optimization Of Broad Area Quantum Cascade Laser Performance, Matthew Suttinger

Electronic Theses and Dissertations

Quantum Cascade Lasers are a novel source of coherent infrared light, unique in their tunability over the mid-infrared and terahertz range of frequencies. Advances in bandgap engineering and semiconductor processing techniques in recent years have led to the development of highly efficient quantum cascade lasers capable of room temperature operation. Recent work has demonstrated power scaling with broad area quantum cascade lasers by increasing active region width beyond the standard ~10 ?m. Taking into account thermal effects caused by driving a device with electrical power, an experimentally fitted model is developed to predict the optical power output in both pulsed …

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Predicting Undergraduate Retention In Stem Majors Based On Demographics, Math Ability, And Career Development Factors, Christopher Belser Jan 2017

Predicting Undergraduate Retention In Stem Majors Based On Demographics, Math Ability, And Career Development Factors, Christopher Belser

Electronic Theses and Dissertations

Science, technology, engineering, and math (STEM) fields are currently facing a crisis with respect to filling jobs with qualified workers (NSF, 2013; NAS, 2011). While advancements in these industries have translated into job growth, post-secondary declaration and retention rates within STEM majors lag behind industry needs (Carnevale et al., 2011; Chen, 2013; Koenig et al., 2012). Although researchers previously investigated demographic variables and math-related variables in the context of STEM retention (Beasley & Fischer, 2012; CollegeBoard, 2012; Cundiff et al., 2013; Gayles & Ampaw, 2014; Le et al., 2014; Nosek & Smyth, 2011; Riegle-Crumb & King, 2010), the need exists …

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An Investigation Of State College To University Transfer Students' Sense Of Belonging, Claire Brady Jan 2017

An Investigation Of State College To University Transfer Students' Sense Of Belonging, Claire Brady

Electronic Theses and Dissertations

The purpose of this mixed methods study was to examine the sense of belonging of state college transfer students who enroll at a large research-intensive university through structured and unstructured transfer pathways using the Sense of Belonging Instrument (SBI; Hoffman, Richmond, Morrow, & Solomon, 2002). The SBI includes five subscales (Peer Support, Faculty Support, Classroom Comfort, Isolation, and Empathetic Faculty Understanding). To date, no systematic investigation has considered the construct of belonging with this population or transfer pathway. The findings from this study (n = 54) found a positive statistically significant correlation between Peer Support and Isolation (r(52) =.801, p …

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Examining The Experiences Of Latino/A Parents Of First-Generation College Students Pursuing A Doctoral Degree, Natalia Toro Jan 2017

Examining The Experiences Of Latino/A Parents Of First-Generation College Students Pursuing A Doctoral Degree, Natalia Toro

Electronic Theses and Dissertations

Research points to Latino/a parents as an important source of motivation and support for high achieving Latino/a students who are the first in their families to go to college (Arellano & Padilla, 2006; Gandara, 1982; 1994; Hurtado & Sinha, 2006; Zalaquett, 2005); however, very little is known about their experience as they parent children whose educational paths are so different from their own. Cultural values such as collectivism and familism play a unique role in the level of connection between these parents and their children (Suarez-Orozco & Suarez-Orozco, 1995), creating dynamics that merit exploration. This dissertation qualitatively examines how seven …

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Coloring Graphs With Forbidden Minors, Martin Rolek Jan 2017

Coloring Graphs With Forbidden Minors, Martin Rolek

Electronic Theses and Dissertations

A graph H is a minor of a graph G if H can be obtained from a subgraph of G by contracting edges. My research is motivated by the famous Hadwiger's Conjecture from 1943 which states that every graph with no Kt-minor is (t − 1)-colorable. This conjecture has been proved true for t ≤ 6, but remains open for all t ≥ 7. For t = 7, it is not even yet known if a graph with no K7-minor is 7-colorable. We begin by showing that every graph with no Kt-minor is (2t − 6)- colorable for t = …

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Charge And Spin Transport In Low-Dimensional Materials, Amin Ahmadi Jan 2017

Charge And Spin Transport In Low-Dimensional Materials, Amin Ahmadi

Electronic Theses and Dissertations

My research has been focused on two main areas. First, electronic transports in chiral carbon nanotubes in the presence of charged adatoms. To study such systems we employed recursive Greens function technique to evaluate the conductance using the Landauer formula. Comparing with the experimental data, we determined the effective amplitude and the range of scattering potentials. In addition, using a similar approach we explained qualitatively an unusual conductance feature in a metallic carbon nanotube. The second part of my study was concerned to the dynamical spin injection and spin currents in low-dimensional materials. We have developed an atomistic model to …

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An Exploration Of The Feasibility Of Functional Near-Infrared Spectroscopy As A Neurofeedback Cueing System For The Mitigation Of The Vigilance Decrement, Gabriella Hancock Jan 2017

An Exploration Of The Feasibility Of Functional Near-Infrared Spectroscopy As A Neurofeedback Cueing System For The Mitigation Of The Vigilance Decrement, Gabriella Hancock

Electronic Theses and Dissertations

Vigilance is the capacity for observers to maintain attention over extended periods of time, and has most often been operationalized as the ability to detect rare and critical signals (Davies & Parasuraman, 1982; Parasuraman, 1979; Warm, 1984). Humans, however, have natural physical and cognitive limitations that preclude successful long-term vigilance performance and consequently, without some means of assistance, failures in operator vigilance are likely to occur. Such a decline in monitoring performance over time has been a robust finding in vigilance experiments for decades and has been called the vigilance decrement function (Davies & Parasuraman, 1982; Mackworth, 1948). One of …

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Impacts Of Workplace Violence: The Role Of Inequality, Lindsey Singer Jan 2017

Impacts Of Workplace Violence: The Role Of Inequality, Lindsey Singer

Electronic Theses and Dissertations

In 2011 the National Crime Victimization Survey (NCVS) reported that of people who are employed and aged 16 and older, 24% of nonfatal violent incidents happened at work. To understand the magnitude of the problem, from 2005 to 2009, 572,000 nonfatal workplace crimes occurred against people aged 16 or older. Annually, the rate of workplace violence was about 5 victimizations per 1,000 employed persons aged 16 and older (Harrell 2011). The impact of crime on victims is a topic that deserves attention because it extends our understanding beyond descriptive rates of violence. Workplace victimization, like most other types of victimizations …

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