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Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer
Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer
UNLV Theses, Dissertations, Professional Papers, and Capstones
Structural health monitoring (SHM) of an instrumented structure provides numerous benefits when assessing the long-term condition of the structure against degradation, or the short-term condition after an extreme event, such as an earthquake. The Nevada Department of Transportation (NDOT) has an interest in expanding the use of SHM for such assessments. Accordingly, the objective of the current study is to develop and implement a permanent SHM system for the Galena Creek Bridge, the largest concrete cathedral arch bridge in the world, to monitor its response to routine traffic and seismic activity. Completed in 2012, the bridge connects Reno and Carson …
Microbial-Mediated Removal Of Acrylamide From Canal Systems, Stephanie Kay Labahn
Microbial-Mediated Removal Of Acrylamide From Canal Systems, Stephanie Kay Labahn
UNLV Retrospective Theses & Dissertations
Acrylamide (AMD), a neurotoxin and suspected carcinogen, is present up to 0.05% in linear anionic polyacrylamide (PAM) which is being evaluated as a canal sealant across the western United States. The capacity of canal microorganisms to facilitate AMD degradation was examined to constrain risks of PAM applications. AMD degradation under simulated groundwater flow was determined with soil column tests (repacked and soil cores) and spiked bottle tests verified microbial degradation under in situ and ex situ conditions. Results of the repacked columns indicate AMD degradation in the presence of competing substrates with half-lives ranging from 0.9 to 3.12 hours. Soil …
Thermal Modeling Of A High Concentration Photovoltaic System, Aaron M Sahm
Thermal Modeling Of A High Concentration Photovoltaic System, Aaron M Sahm
UNLV Retrospective Theses & Dissertations
A two-dimensional numerical model was developed to simulate a single chamber with an array of cells for a high concentration photovoltaic system. Gambit was used to generate the computational mesh and Fluent was used to obtain the numerical simulation results. The cells were treated as heat sources with efficiencies that change as a function of temperature. Initially a simulation was run with an assumed cell efficiency of 25%. After the maximum temperature was determined, the cell efficiency was calculated and input into the model to recalculate the temperature solution. Radiation and convection modes of heat transfer were the primary focus …
Implementation Of Recursive Queries For Information Systems, Jayalakshmi Jeyaraman
Implementation Of Recursive Queries For Information Systems, Jayalakshmi Jeyaraman
UNLV Retrospective Theses & Dissertations
Sophisticated information systems require a powerful query language and an efficient implementation strategy. In practice, these information systems are either built on the top of an existing database management system or built as an expert system with deductive capabilities. Both of these implementations must provide a mechanism to express recursive queries. It is therefore a necessity for the system to have an efficient algorithm to evaluate these queries. In this thesis, we give a detailed description of a bibliographic database, a set of recursive queries, an overview of some standard query processing algorithms, and an implementation of these queries in …
Development Of A Gis-Based Safety Analysis System, Vidhya Kumaresan
Development Of A Gis-Based Safety Analysis System, Vidhya Kumaresan
UNLV Retrospective Theses & Dissertations
The objective of this study is to develop a safety analysis system that integrates crash data and roadway related information. This system is developed in a Geographic Information System (GIS) environment. It includes customized user interfaces to support queries to analyze data and to display results either in graphical or tabular formats. The system also affords the capabilities to export such results. The system permits analyses to be performed either at individual locations such as intersections, or for roadway segments. These analyses are based on data fields included in the crash database. The queries may be based on individual attributes …
Mathematical Model To Simulate A Hybrid Lighting System, Ahmad Abu Heiba
Mathematical Model To Simulate A Hybrid Lighting System, Ahmad Abu Heiba
UNLV Retrospective Theses & Dissertations
Hybrid solar lighting (HSL) technology is a relatively new technology to utilize natural sunlight along with the traditional electric lighting to light the interior spaces. HSL systems concentrate the sunlight onto a bundle of optical fibers. The optical fibers are routed into the interior space and coupled with cylindrical rods to diffuse the light. A lighting sensor modulates the amount of electric energy depending on the amount of natural light available; This study presents a simplified mathematical model to predict the output of the HSL system based on the amount of the available solar radiation. The model is verified via …
Exploratory Study Of Construction Safety Culture Through Systems Thinking, Charles J. Jr Benford
Exploratory Study Of Construction Safety Culture Through Systems Thinking, Charles J. Jr Benford
UNLV Retrospective Theses & Dissertations
Since its conception, in 1986 after the Chernobyl accident, the term "safety culture" has gained major popularity throughout many systems, especially the construction industry. Although this concept has gained much popularity over the course of two decades, it remains a heavily debated topic between advocates and skeptics for various reasons. Much of the skepticism is due to the failure of proponents of the concept to clearly define and provide an understanding of those factors that comprise what "safety culture" is, and how it can be achieved. A system (particularly a construction system) that possesses a safety culture is one in …
A System Dynamics Approach To Water Resources Planning And Management In South Florida, Dinesh Kumar Prashar
A System Dynamics Approach To Water Resources Planning And Management In South Florida, Dinesh Kumar Prashar
UNLV Retrospective Theses & Dissertations
The primary aim of this research is to test a number of policy options to reduce water consumption in agricultural and municipal sectors, and quantify its impact on environmental supply. A System Dynamics model is developed to evaluate the sustainability of agricultural, municipal, and environmental water demands in South Florida. Performance criteria of vulnerability, resilience, and reliability, are used to measure the success of the policies. In addition, scenarios with varying precipitation and population growth rates are generated to account for uncertainty; The status-quo simulations run from 1970 to 2050 show a reduction in environmental flows after 2010. That can …
Framework For Simulation Of Fault Tolerant Heterogeneous Multiprocessor System-On-Chip, Bisrat Tafesse
Framework For Simulation Of Fault Tolerant Heterogeneous Multiprocessor System-On-Chip, Bisrat Tafesse
UNLV Retrospective Theses & Dissertations
Due to the ever growing requirement in high performance data computation, current Uniprocessor systems fall short of hand to meet critical real-time performance demands in (i) high throughput (ii) faster processing time (iii) low power consumption (iv) design cost and time-to-market factors and more importantly (v) fault tolerant processing. Shifting the design trend to MPSOCs is a work-around to meet these challenges. However, developing efficient fault tolerant task scheduling and mapping techniques requires optimized algorithms that consider the various scenarios in Multiprocessor environments. Several works have been done in the past few years which proposed simulation based frameworks for scheduling …
Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright
Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright
UNLV Retrospective Theses & Dissertations
Understanding the role of nitrate in the speciation of actinides is important in order to determine the necessary data for extraction modeling of the UREX process. The focus of this project is on the fundamental chemistry of uranium (U) in the tributyl phosphate (TBP) extraction system, with emphasis on the effect of nitrate on actinyl speciation. Speciation calculations can be performed if stability and solubility constants for the chemical species formed under the examined conditions are known. The stability constant of the uranyl-TBP complex was evaluated under a variety of conditions. The variables were nitric acid, uranyl, total nitrate concentration, …
Evaluating The Use Of System Dynamics For Improving Stakeholder Decision Making, Marcia Lynne Turner
Evaluating The Use Of System Dynamics For Improving Stakeholder Decision Making, Marcia Lynne Turner
UNLV Retrospective Theses & Dissertations
When lay stakeholders are involved in complex environmental decision making, the ensuing decision does not always effectively solve the problem of focus. This can be due to the fact that standard facilitation methods commonly used to manage such efforts frequently fail to promote thorough and rational decision analysis. A review of classical and behavioral decision theory, stakeholder research and standard facilitation practices suggests that standard facilitation methods tend to enable behavioral decision making strategies which oversimplify decision making tasks, rather than employing classical rational strategies which stress a more thorough decision analysis and maximization of decision outcomes; To test this …
Factors Determining Incorporation Of Innovative Minigrant Programs In Nevada School Systems, O. Dennis Ortwein
Factors Determining Incorporation Of Innovative Minigrant Programs In Nevada School Systems, O. Dennis Ortwein
UNLV Retrospective Theses & Dissertations
This study established the extent to which ESEA Title III Minigrant projects funded in 1973-75 were continuing in Nevada during the 1977-78 school term. Characteristics of the institution and of the innovation found by the Rand Corporation to influence incorporation (continuation) were then compared to four levels of program continuation. Thirty-seven of the forty-two minigrant recipients provided the two sets of data, and the chi-square ((chi)('2)) test was applied to determine that the following Rand Study characteristics inferred continuation of minigrants: strong administrative support, dominant staff training model, active consumer demand, congruence with local priorities, and activities which replace local …
The Development Of A Consensus Management By Objectives Model And A Comparison To The Clark County School District Management And Accountability System For Secondary Schools, Agustin A Orci
UNLV Retrospective Theses & Dissertations
The purpose of the study was to examine selected business and education management by objectives (MBO) models and identify the common elements. These elements resulted in a consensus MBO model which was compared to determine agreement with the Clark County School District's Management and Accountability System for Secondary Schools. Educational accountability, the theoretical bases for MBO and MBO models in business and education were treated in the review of the literature. Graphic models developed in the study included the Clark County District's Management and Accountability System for Secondary Schools and a consensus MBO model; A management process based on the …
Assessing The Homeland Security Advisory System, Ted Greenhalgh
Assessing The Homeland Security Advisory System, Ted Greenhalgh
UNLV Retrospective Theses & Dissertations
Since its inception, the Department of Homeland Security (DHS) was tasked with communicating local and national threat information. Over the last four years, DHS improved its technical ability to communicate, but many people still question its actions. Often it seems that regardless of the message released by DHS, somebody will criticize either the message content or the tuning of the press release. This begs the question of how effective is DHS at delivering messages and if it can be improved. Using a checklist of effective communication strategies, this study evaluated eighteen DHS press releases that identified new threats. The study …
Extending The Delone And Mclean Information Systems Success Model For E-Commerce Website Success, Joy Wendy Wu
Extending The Delone And Mclean Information Systems Success Model For E-Commerce Website Success, Joy Wendy Wu
UNLV Retrospective Theses & Dissertations
Website evaluation can continuously improve the performance of websites and increase sales. However, the lack of a comprehensive framework as guidance hampered this task. The main purpose of this research is to provide a comprehensive framework for e-commerce websites evaluation by extending the DeLone and McLean Information System Success Model. A new dimension---"Relationship quality" is proposed to the model. The study also tries to identify characteristics of e-commerce websites that impact the user's satisfaction; A survey questionnaire was distributed to web users, and a total of 295 responses were obtained. The data was processed through Statistical Package for the Social …
A Numerical Prediction Of The Thermal Environment Of A Room Heated With A Hydronic Heating System, Satya Kiran C Gurram
A Numerical Prediction Of The Thermal Environment Of A Room Heated With A Hydronic Heating System, Satya Kiran C Gurram
UNLV Retrospective Theses & Dissertations
The systems in which water or steam carries heat to the areas to be heated are Hydronic heating systems. Hydronic systems are closed loop where water is heated in a boiler and circulated through pipes to a heat transfer component such as a radiator or finned-tube baseboard unit. The systems can be used to effectively control the air temperature and the mean radiant temperature of an enclosure; Two numerical model of a room one without a window and the other with a window using a flat panel baseboard heating systems were simulated using StarCd. The effects of temperature on the …
Nonlinear And Adaptive Control Systems For Underwater And Air Vehicles, Pradeep Nambisan
Nonlinear And Adaptive Control Systems For Underwater And Air Vehicles, Pradeep Nambisan
UNLV Retrospective Theses & Dissertations
This thesis considers the design of nonlinear and adaptive control systems for the control of submersibles as well as aircraft. In the first part of the thesis, control of submersibles using bow and stern hydroplanes is considered, and (i) a robust output feedback nonlinear control law using modeling error compensation, (ii) a nonlinear adaptive state feedback law using SDU decomposition; and (iii) an output feedback linear adaptive law for the dive-plane maneuvering are derived. The robust nonlinear controller with high-gain observer is designed for depth and pitch angle tracking along constant trajectories in the presence of parametric uncertainties and disturbances …
Design Of Sputtering System For Hemispherical Boron 10 Target, Priya Raman
Design Of Sputtering System For Hemispherical Boron 10 Target, Priya Raman
UNLV Retrospective Theses & Dissertations
10Boron (10B) is an isotope of Boron. 10B and neutron interaction yields alpha particles. alpha particles typically deposit their energy within a few tenths of nanometers within a semiconductor creating electron-hole pairs which through radiative recombination yield photon emission of band gap energy. The number of photons emitted directly relates to the energy and flux density of incoming neutron. Thus, 10B coated semiconductors can be used as a neutron detectors. 10B is an expensive material, especially in the disc and the powdered form which is needed for sputtering. Since a hemispherical target of 10B of diameter 4.8cm was available, a …
Collaborative Intelligent Email Ranking System, Nathaniel H Whittacre
Collaborative Intelligent Email Ranking System, Nathaniel H Whittacre
UNLV Retrospective Theses & Dissertations
Email has become one of the most powerful communication tools today. It is has widely proliferated in both business and personal use. It allows for fast communication between multiple parties that can be easily understood by even the most novice user, and allows for advanced transfer of data for power users. Even with that, it is one of the most abused systems on the Internet. Email systems have allowed for widespread distribution of the worst viruses on the Internet, causing billions of dollars in damage. Most of the technologies that have been deployed to prevent these types of attacks have …
Numerical Simulation Of Thermal Comfort And Contaminant Transport In Rooms With Ufad System, Rama Haritha Bandarupalli
Numerical Simulation Of Thermal Comfort And Contaminant Transport In Rooms With Ufad System, Rama Haritha Bandarupalli
UNLV Retrospective Theses & Dissertations
This thesis deals with the numerical simulation of the thermal comfort and contaminant transport of an under floor air distribution (UFAD) system. Within the last few years, UFAD systems have become popular design alternative to conventional distribution (CAD) such as overhead distribution systems for thermal and ventilation control. Recent advances in computational fluid dynamics (CFD) and computer power make it possible to accurately predict some features of airflow within ventilated spaces. The CFD method has been successfully applied for airflow analysis in relatively complicated conditions, such as non-isothermal, three-dimensional and with furniture inside the room. The goal of this research …
Video Based Vehicle Detection For Advance Warning Intelligent Transportation System, Naveen Chintalacheruvu
Video Based Vehicle Detection For Advance Warning Intelligent Transportation System, Naveen Chintalacheruvu
UNLV Retrospective Theses & Dissertations
Video based vehicle detection and surveillance technologies are an integral part of Intelligent Transportation System (ITS), due to its non-intrusiveness and capability or capturing global and specific vehicle behavior data. The initial goal of this thesis is to develop an efficient advance warning ITS system for detection of congestion at work zones and special events based on video detection. The goals accomplished by this thesis are: (1) successfully developed the advance warning ITS system using off-the-shelf components and, (2) Develop and evaluate an improved vehicle detection and tracking algorithm. The advance warning ITS system developed includes many off-the-shelf equipments like …
Development Of A Safety Analysis And An Intersection Infrastructure System, Ancila V Kaiparambil
Development Of A Safety Analysis And An Intersection Infrastructure System, Ancila V Kaiparambil
UNLV Retrospective Theses & Dissertations
GIS and GPS technologies have found immense applications in the field of transportation engineering. Different features related to transportation safety are inventoried using these technologies. The databases so created serve as main source for safety analyses, decision making and reporting. Many different analyses tools are available to assist engineers, planners and policy makers in the process of improving transportation safety. GIS-based analyses tools provide tabular and graphic display, thereby expediting the analyses process and improving the spatial understanDing The advantages of such tools increase if they can be provided on the World Wide Web. One such software system that offers …
Buffer Allocation In Message Passing Systems: An Implementation For Mpi, Jeffrey Sampson
Buffer Allocation In Message Passing Systems: An Implementation For Mpi, Jeffrey Sampson
UNLV Retrospective Theses & Dissertations
Message passing applications that perform asynchronous communication need sufficient buffer space to hold all undelivered messages, or else the applications may deadlock. Determining the minimum amount of buffer space an application needs is called the Buffer Allocation Problem, and has been shown to be intractable [BPW]. However, an epoch based polynomial-time algorithm that approximates the Buffer Allocation Problem has been proposed by Pedersen et al. [PBS]. The algorithm partitions application executions into epochs and intersperses barrier synchronizations between them, thus limiting the number of message buffers necessary to ensure deadlock-freedom; In this thesis, we describe an implementation of the epoch …
Graphic Frameworks For Managing Component Oriented Graphic Systems, Deepa Uppala
Graphic Frameworks For Managing Component Oriented Graphic Systems, Deepa Uppala
UNLV Retrospective Theses & Dissertations
This thesis presents a model graphic framework. It uses traditional graphic principles such as display file concepts to generate frameworks. It implements object oriented patterns such as inheritance polymorphism etc. to reuse the graphic framework for the object oriented graphic applications; This thesis suggests component technology such as Microsoft COM technology to make the frameworks effective. The thesis identifies the advantage of Component Oriented Technology over Object Oriented Technology. The procedure for development of a Component is complex. Even the client procedure for using the component is also complex. This thesis presents a model procedure for the development of a …
Development Of Seat Shock Isolation Systems, Erik Wolf
Development Of Seat Shock Isolation Systems, Erik Wolf
UNLV Retrospective Theses & Dissertations
A numerical model has been created to predict the behavior of seat shock isolation systems exposed to mine blast loaDing The model is a two dimensional, five degree-of-freedom, rigid body, mass-spring-damper approximation of the seat system and human occupant. The outputs of the model are the positions, velocities, and accelerations of the system masses, the forces of the connecting elements, such as the seat cushion force, the load limiter force, the spinal force, and the Dynamic Response Index (DRI) based on the pelvic z-axis acceleration. The model has been calibrated with drop tower test data collected by the Army Research …
Missing And Abducted Children: A Critical Analysis Of The Amber Alert System, Michael John Smoll
Missing And Abducted Children: A Critical Analysis Of The Amber Alert System, Michael John Smoll
UNLV Retrospective Theses & Dissertations
Originally created from the reaction of a child abducted and murdered by a stranger, the AMBER alert system has since been utilized for a wide variety of child abduction episodes. The AMBER alert system has the potential to provide millions of citizens with descriptive information about a missing or abducted child in the hopes that the child can be successfully recovered by utilizing a wide array of communication mediums. This current study examined a sample of AMBER alerts issued in twelve states during the year 2005. Among the key findings include the fact that the vast majority of AMBER alerts …
Analysis Of Runtime Re-Configuration Systems, Utthaman Thirunavukkarasu
Analysis Of Runtime Re-Configuration Systems, Utthaman Thirunavukkarasu
UNLV Retrospective Theses & Dissertations
In recent years Programmable Logic Devices (PLD) and in particular Field Programmable Gate Arrays (FPGAs) have seen a tremendous increase in sales and applications in the area of embedded systems. The main advantage of FPGAs is the flexibility that they offer a designer in reconfiguring the hardware. The flexibility achieved through re-configuration of FPGAs usually incurs an overhead of extra execution time, data memory and also power dissipation; FPGAs provide an ideal template for run-time reconfigurable (RTR) designs. Only recently have RTR enabling design tools that bypass the traditional synthesis and bitstream generation process for FPGAs become available, JBits is …
Optical Interferometry With Detector System To Measure Perturbations In Plastics, Satya Sundeep Gurujala Radhakrishna
Optical Interferometry With Detector System To Measure Perturbations In Plastics, Satya Sundeep Gurujala Radhakrishna
UNLV Retrospective Theses & Dissertations
The Nevada Shocker is a pulsed power machine composed of a 540 kV (maximum), 4.54 kJ (maximum) Marx Bank in series with a 50 ns pulse forming Blumlein activated by a self breaking water switch. The energy released by the water dielectric Blumlein is guided by a water-filled coaxial line to a vacuum chamber containing a parallel plate diode. A cylinder of Rexolite plastic is sandwiched in between the parallel plate diode electrodes. The applied field mechanically stresses the electrodes on a molecular level generating a shock wave that changes the localized index of refraction. Further during discharge, the applied …
Development Of An Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Matthew S Hodges
Development Of An Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Matthew S Hodges
UNLV Retrospective Theses & Dissertations
Major issues concerning nuclear waste storage at Yucca Mountain are that of safety and long term disposal. Approximately one percent of the content of spent nuclear fuel is that which is responsible for nearly all the long-term associated health risks. The removal and transmutation of this content will render the toxicity of the remaining waste to that of natural uranium within a few hundred years. The research contained in this thesis details several simulations that are involved in the overall removal process. The first objective was to test the feasibility of the design of a distillation column that will separate …
Ubiquitous Health Monitoring System For Seniors, Kamesh Khanna Andisamy Vijayakumar
Ubiquitous Health Monitoring System For Seniors, Kamesh Khanna Andisamy Vijayakumar
UNLV Retrospective Theses & Dissertations
The Ubiquitous Health Monitoring System for Seniors is a prototype for an implantable module that is designed to eliminate critical delays in receiving medical attention upon the development of a heart attack. In particular, the prototype is to detect the onset of heart attacks in real time, and to use a Bluetooth wireless link to signal the patient's mobile phone to dial emergency personnel in the event of an abnormality. The unit also records and logs the temperature of the user. Since the unit holds a GPS in it the current position of the user can be constantly monitored and …