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Articles 1 - 30 of 55
Full-Text Articles in Engineering
Spectral And Temporal Interrogation Of Cerebral Hemodynamics Via High Speed Laser Speckle Contrast Imaging, Rex Chin-Hao Chen
Spectral And Temporal Interrogation Of Cerebral Hemodynamics Via High Speed Laser Speckle Contrast Imaging, Rex Chin-Hao Chen
Theses and Dissertations
Laser Speckle Contrast Imaging (LSCI) is a non-scanning wide field-of-view optical imaging technique specifically developed for cerebral blood flow (CBF) monitoring. In this project, a versatile Laser speckle contrast imaging system has been designed and developed to monitor CBF changes and examine the physical properties of cerebral vasculature during functional brain activation experiments.
The hardware of the system consists of a high speed CMOS camera, a coherent light source, a trinocular microscope, and a PC that does camera controlling and data storage. The simplicity of the system’s hardware makes it suitable for biological experiments.
In controlled flow experiments using a …
An Economical Model Development For A Hybrid System Of Grid Connected Solar Pv And Electrical Storage System, Mohammad Hasan Balali
An Economical Model Development For A Hybrid System Of Grid Connected Solar Pv And Electrical Storage System, Mohammad Hasan Balali
Theses and Dissertations
Energy sources management is one of the most important concern in the recent decades. There are finite amount of non-renewable energy sources and one day they will run out if they have been used as primary sources of energy. Renewable energy sources have been significantly reduced the environmental effects. For most of them the source of energy is non-depletable.
One of the concerns associated with renewable resources is uncertainty or unavailability. Energy Storage Systems (ESSs) can help to have more reliable and more efficient systems by adjusting the charge and discharge time and rate. In this study, an economic model …
Warranty Period And Product Price Optimization For Remanufactured Products, Yuxi Liu
Warranty Period And Product Price Optimization For Remanufactured Products, Yuxi Liu
Theses and Dissertations
This study considers a remanufactured electrical product under a tiered warranty policy. Warranty is key in ensuring a good manufacturer—consumer relationship. Manufacturers hope to minimize warranty costs while consumers believe that good warranty promises better product quality and reliability. This Thesis presents an optimal warranty period from the perspective of a manufacturer to maximize the total expected profits, while ensuring sustained consumer relation. We use real data from a local company with a global supply chain to provide a numerical example.
Finite Element Analysis (Fea) Study Of The Thermal Stress Concentrations In Planar-Type Sodium Sulfur (Nas) Secondary Batteries, Jeffrey P. Colker
Finite Element Analysis (Fea) Study Of The Thermal Stress Concentrations In Planar-Type Sodium Sulfur (Nas) Secondary Batteries, Jeffrey P. Colker
Theses and Dissertations
The importance of a reliable and safe way to store energy, and allow for on-demand usage, has led to much research in the field of secondary battery development. The thesis herein explores a technology that has shown promising results when implemented in large-scale energy grid applications. Though the technology has proven viable in both load-leveling on existing grids as well as serving to legitimize renewable energy sources, the development of such advanced battery systems is not without challenge. Sodium-sulfur (NaS) secondary cells have shown promising results when implemented in the aforementioned energy storage applications. One of the main drawbacks to …
Biomechanical Evaluation Of Three Post-Kneeling Tasks: Sitting, Walking, And Standing, Alexa Hernandez Principe
Biomechanical Evaluation Of Three Post-Kneeling Tasks: Sitting, Walking, And Standing, Alexa Hernandez Principe
Theses and Dissertations
There are several occupations that require prolonged kneeling as part of their daily practice. Employees who kneel for a prolonged period of time have been reported to have high rates of knee and low back musculoskeletal disorders (Coggon et al. 2000, Halmstrom et al. 1992, Harkness et al. 2003, Manninen et al. 2002). These disorders result in excessive worker’s compensation costs. Gallagher el al. (2009) looked at the low seam mining industry and found that companies spent the most on knee related injuries with $4.2 million and $2.7 million for low back injuries.
There is a lack of knowledge available …
Experimental Evaluation Of Beneficial Use Of Lake Michigan Dredged Materials In Flyash Based Geopolymer Concrete, Sara Dashti
Experimental Evaluation Of Beneficial Use Of Lake Michigan Dredged Materials In Flyash Based Geopolymer Concrete, Sara Dashti
Theses and Dissertations
Dredging harbors and rivers are necessary to maintain the appropriate water depth for navigation. However the disposal facilities for storing dredged materials around the U.S. Great Lakes are at or near their capacities and finding beneficial uses for these materials is a major concern. On the other hand, carbon emission and global warming have become the greatest environmental issues during the last decade. Cement manufacturing is a major contributor to CO2 release into the atmosphere. The objective of this study was to develop a low-cost, environment-friendly geopolymer concrete paste with dredged materials as a substantial mix ingredient. Geopolymer concrete does …
Adaptation Of Moiré Phase Tracking To A Mobile Device For Field 3d Data Collections, Amar Nikhanj
Adaptation Of Moiré Phase Tracking To A Mobile Device For Field 3d Data Collections, Amar Nikhanj
Theses and Dissertations
The accelerating technologies of mobiles devices such as tablets and phones provide an ability to
perform high intensity calculations all while obtaining precise data with increasingly more accurate
sensors. Image metrology and 3D motion tracking can take advantage of these improvements as
they require both significant processing power and camera controls not seen in mobile devices until
very recently. This thesis discusses the development of 3D motion tracking using Google Nexus
tablets and applying the technology to the Rapid Upper Limb Assessment (RULA) to demonstrate
the technology’s application to field measurements. RULA analysis determines the stress placed on
a human …
Monitoring And Modeling The Hydrological Performance Of Extensive Green Roof Systems, Joseph Seidl
Monitoring And Modeling The Hydrological Performance Of Extensive Green Roof Systems, Joseph Seidl
Theses and Dissertations
Urban stormwater runoff causes many problems for watersheds located within large metropolitan areas, including such detrimental effects as flooding, erosion, pollution, and the increased risk of combined sewerage overflows. Increased amounts of impervious areas resulting from urban sprawl have also been shown to escalate stormwater flows, which exacerbates water management issues in these metropolitan areas. Water resource engineers have progressively turned toward green infrastructure to solve stormwater problems, and green roof systems represent one type of this green infrastructure. As of current, however, green roof systems are largely underused in as an effective stormwater management tool.
The major factor limiting …
Hydrodynamic Modeling Of The Green Bay Of Lake Michigan Using The Environmental Fluid Dynamics Code, Paula Estefania Cedillo
Hydrodynamic Modeling Of The Green Bay Of Lake Michigan Using The Environmental Fluid Dynamics Code, Paula Estefania Cedillo
Theses and Dissertations
In this project we created a hydrodynamic model of the Lower Green Bay of Lake Michigan in Wisconsin, United States using the Visual Environmental Fluid Dynamics Code (EFDC). The model includes four tributary rivers to Lower Green Bay as well as the open boundary flow conditions at Chambers Island. This case study is used to: 1) compare the results obtained with a previous study of Lower Green Bay to validate the creation of the model 2) examine the hydrodynamics of the bay, and 3) create a framework for future studies at Lower Green Bay. The Geographic Information used to build …
Field And Laboratory Study Of The Flàajökull Glacier, Iceland, William Russell Jacobson, Jr.
Field And Laboratory Study Of The Flàajökull Glacier, Iceland, William Russell Jacobson, Jr.
Theses and Dissertations
The increased surface melting of the outlet glaciers of the Vatnajökull Ice Cap has a profound affect on the dynamics of the ice-bed couple and landform genesis. Soft-bedded glaciers are largely inaccessible, which creates a problem. One challenge is to understand the complex interactions of the glacier bed and its resultant depositional and deformational landform systems. This study investigates an outlet glacier from the Vatnajökull Ice Cap, described herein as the Fláajökull glacier system. To circumvent some of these problems, three separate projects were conducted in this dissertation: (1) magnetic fabric study of effective pressure (difference between the ice-overburden pressure …
Multi-Level Optimal Design Using Game Theory With Model Updating By Low Discrepancy Sampling, Yanchen Xu
Multi-Level Optimal Design Using Game Theory With Model Updating By Low Discrepancy Sampling, Yanchen Xu
Theses and Dissertations
The Design of Experiment (DOE) based response surface methodology (RSM) is a commonly used technique for solving optimization problems. The traditional DOE method has some shortcomings when used to update the RSM model. This thesis aims to develop a new DOE technique to solve the model updating problems in design optimization. Toward this end, a new DOE based RSM method is proposed to solve this problem by using low-discrepancy sequence method to generate the additional data points needed to update the model to replace the traditional factor and level based DOE method.
Tested on a couple of numerical example problems, …
Indicator Bacteria In Beach Environments, Brett Bevers
Indicator Bacteria In Beach Environments, Brett Bevers
Theses and Dissertations
Bacterial presence in the environment has become a growing concern in recent years. The exposure of the public to elevated levels of microbes in the environment has been linked with respiratory and gastrointestinal illnesses. It is important to understand the behavior of bacteria in the environment in order to address public health concerns. This project was intended to improve our understanding of bacteria in the environment that are used as indicators for fecal pollution. Using the standard indicator species E. coli and Enterococci data was collected at Bradford Beach in Milwaukee Wisconsin throughout the summer months of 2013 and 2014. …
A Systems Approach To Point Source Indication Of Metformin Found In Local Water Systems – The Case Of Milwaukee County, Mohamed Salem Baitelmal
A Systems Approach To Point Source Indication Of Metformin Found In Local Water Systems – The Case Of Milwaukee County, Mohamed Salem Baitelmal
Theses and Dissertations
Pharmaceutical pollutants are present in traceable concentrations in Milwaukee County water system and Lake Michigan. The actual point sources and nature of entry into the water system is difficult to determine with certainty. Pharmaceuticals have been found to persist at the South Shore Wastewater Treatment Facility (SSWTF) in Milwaukee, Wisconsin. The highest concentration was found to be for the pharmaceutical drug metformin. Metformin is a first line drug for the treatment of type 2 diabetes mellitus.
The broad goal of this exploratory study; the first of its kind, is to correlate trace concentrations of drugs to the point sources. Particularly, …
Water Withdrawal And Consumption Reduction Analysis For Electrical Energy Generation System, Narjes Nouri
Water Withdrawal And Consumption Reduction Analysis For Electrical Energy Generation System, Narjes Nouri
Theses and Dissertations
There is an increasing concern over shrinking water resources. Water use in the energy sector primarily occurs in electricity generation. Anticipating scarcer supplies, the value of water is undoubtedly on the rise and design, implementation, and utilization of water saving mechanisms in energy generation systems are becoming inevitable. Most power plants generate power by boiling water to produce steam to spin electricity-generating turbines. Large quantities of water are often used to cool the steam in these plants. As a consequence, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn …
Investigation Of Electrolyte Wetting In Lithium Ion Batteries: Effects Of Electrode Pore Structures And Solution, Yangping Sheng
Investigation Of Electrolyte Wetting In Lithium Ion Batteries: Effects Of Electrode Pore Structures And Solution, Yangping Sheng
Theses and Dissertations
Beside natural source energy carriers such as petroleum, coal and natural gas, the lithium ion battery is a promising man-made energy carrier for the future. This is a similar process evolved from horse-powered era to engine driven age. There are still a lot of challenges ahead like low energy density, low rate performance, aging problems, high cost and safety etc.
In lithium ion batteries, investigation about manufacturing process is as important as the development of material. The manufacturing of lithium ion battery, including production process (slurry making, coating, drying etc.), and post-production (slitting, calendering etc.) is also complicated and critical …
Modeling The Feasibility Of Corn Stover Combustion As A Heat Source At Corn Ethanol Plants, Sulekha Tamvada
Modeling The Feasibility Of Corn Stover Combustion As A Heat Source At Corn Ethanol Plants, Sulekha Tamvada
Theses and Dissertations
Alternative energy sources are of prime interest for most of the nations across the world. Rising fuel prices and depleting petroleum reserves are of serious national and global concern. Bio-fuels if proved feasible for larger scale implementation could become the ideal breakthrough in easing the extensive dependence on fossil fuels and retaining the current engine technology of fossil fuels. Current methods of producing bio-fuels rely heavily on the consumption of non-renewable energy in the production process. Therefore, it is desirable to find renewable alternatives to these non-renewable energy sources.
Although bio-mass based fuels have been tested and proven to be …
Bus Route Operational Efficiency Evaluation In Milwaukee County, Ebtesam Hazbavi
Bus Route Operational Efficiency Evaluation In Milwaukee County, Ebtesam Hazbavi
Theses and Dissertations
ABSTRACT
BUS ROUTE OPERATIONAL EFFICIENCY EVALUATION IN MILWAUKEE COUNTY
by
Ebtesam Hazbavi
The University of Wisconsin-Milwaukee, 2015
Under the Supervision of Professor Yue Liu
Public transit systems are expanding in the majority of cities in the United States due to the increasing numbers of people who use public transportation as their main commute facility. Evaluating the efficiency of public transit systems results in providing better services for the residents on one hand and reduces the unnecessary costs on the other hand.
In this research, the efficiencies of bus routes options in County are evaluated. After reviewing different literature, Fuzzy AHP …
Thermodynamic And Kinetic Simulation Of Transient Liquid-Phase Bonding, Brad Allen Lindner
Thermodynamic And Kinetic Simulation Of Transient Liquid-Phase Bonding, Brad Allen Lindner
Theses and Dissertations
ABSTRACT
THERMODYNAMIC AND KINETIC SIMULATION OF TRANSIENT LIQUID-PHASE BONDING
by
Brad Lindner
The University of Wisconsin-Milwaukee, 2015
Under the Supervision of Professor Benjamin C. Church
The use of numeric computational methods for the simulation of materials systems is becoming more prevalent and an understanding of these tools may soon be a necessity for Materials Engineers and Scientists. The applicability of numerical simulation methods to transient liquid-phase (TLP) bonding is evaluated using a type 316L/MBF-51 material system. The comparisons involve the calculation of bulk diffusivities, tracking of interface positions during dissolution, widening, and isothermal solidification stages, as well as comparison of …
Design And Comparison Of Si-Based And Sic-Based Three-Phase Pv Inverters, Wei Fu
Design And Comparison Of Si-Based And Sic-Based Three-Phase Pv Inverters, Wei Fu
Theses and Dissertations
The opportunities for both power density and efficiency improvements of photovoltaic (PV) inverter have come with the development of commercially available wide bandgap (WBG) devices such as Gallium Nitride (GaN), and Silicon Carbide (SiC).
In this thesis, how the replacement of Silicon (Si) Insulated Gate Bipolar Transistor (IGBT), with SiC Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) affects the power density and efficiency of a solar inverter implementation is presented. The focus is on achieving a minimum volume of the output filter which meet the current harmonic performance of IEEE standard, while meeting the thermal constraint of the semiconductor device. Efficiency improvements …
Influence Of Frame Stiffness And Rider Position On Bicycle Dynamics: An Analytical Study, Trevor Alan Williams
Influence Of Frame Stiffness And Rider Position On Bicycle Dynamics: An Analytical Study, Trevor Alan Williams
Theses and Dissertations
Advanced analytical and computational capabilities are allowing researchers to enhance the model complexity of bicycles and motorcycles in order to understand handling, stability and dynamic behavior. These models allow designers to investigate new frame layouts, alternative materials and different architectures. The structural stiffness of a frame plays a critical role in the handling behavior of a bike. However, the influence of structural stiffness has received limited attention in the existing literature. This study attempts to fill the gap by presenting analytical results that investigate the influence of structural stiffness in conjunction with rider positions on three distinct bicycle layouts. The …
Inverse Approaches For Recovery Of Distributed Loads, Aleysha Kobiske
Inverse Approaches For Recovery Of Distributed Loads, Aleysha Kobiske
Theses and Dissertations
Inverse load recovery is a well-researched topic which involves determining an unknown force acting on a structure from the induced strain. The methodology used to determine an unknown loading imposed on a structure begins with a finite element model of the structure. Unit loads are applied at each known load location and the strain data is collected from the model. The strain data collected from the structure during operation or from simulation is compared to the strain produced from the unit loads. The result is an estimate of the imposed load.
In order to obtain the best results possible for …
Classification Of Adequate Impact Protection For Hands, Patrick Dylan Loshek
Classification Of Adequate Impact Protection For Hands, Patrick Dylan Loshek
Theses and Dissertations
ABSTRACT
CLASSIFICATION OF ADEQUATE
IMPACT PROTECTION FOR HANDS
by
Patrick D. Loshek
The University of Wisconsin-Milwaukee, 2015
Under the Supervision of Professor Naira Campbell-Kyureghyan
Historically, hand injuries have been a large burden for the manufacturing, construction, mining, oil and gas industries. Specially designed gloves are commonly used in industry today to protect hands from impacts. These gloves are designed to reduce hand injuries by absorbing the impact forces workers may encounter due to objects striking the hand. However, to date, there is no standard for the testing of these gloves and quantifying the force reduction a user would experience when …
Intelligent Novel Methods For Identifying Critical Components And Their Combinations For Hypothesized Cyber-Physical Attacks Against Electric Power Grids, Ming Wang
Theses and Dissertations
As a revolutionary change to the traditional power grid, the smart grid is expected to introduce a myriad of noteworthy benefits by integrating the advanced information and communication technologies in terms of system costs, reliability, environmental impacts, operational flexibility, etc. However, the wider deployment of cyber networks in the power grid will bring about important issues on power system cyber security. Meanwhile, the power grid is becoming more vulnerable to various physical attacks due to vandalism and probable terrorist attacks. In an envisioned smart grid environment, attackers have more entry points to various parts of the power grid for launching …
Transient Performance Analysis Of Serial Production Lines, Yang Sun
Transient Performance Analysis Of Serial Production Lines, Yang Sun
Theses and Dissertations
TRANSIENT PERFORMANCE ANALYSIS OF
SERIAL PRODUCTION LINES
by
Yang Sun
The University of Wisconsin-Milwaukee, 2015
Under the Supervision of Professor Liang Zhang
Production lines with unreliable machines and finite buffers are characterized by both steady-state performance and transient behavior. The steady-state performance has been analyzed extensively for over 50 years. Transient behavior, however, is rarely studied and remains less explored. In practice, a lot of the real production systems are running partially or entirely in transient periods. Therefore, transient analysis is of significant practical importance.
Most of the past research on production systems focuses on discrete materials flow which utilities …
The Optimization Of Concrete Mixtures For Use In Highway Applications, Mohamadreza Moini
The Optimization Of Concrete Mixtures For Use In Highway Applications, Mohamadreza Moini
Theses and Dissertations
Portland cement concrete is most used commodity in the world after water. Major part of civil and transportation infrastructure including bridges, roadway pavements, dams, and buildings is made of concrete. In addition to this, concrete durability is often of major concerns. In 2013 American Society of Civil Engineers (ASCE) estimated that an annual investment of $170 billion on roads and $20.5 billion for bridges is needed on an annual basis to substantially improve the condition of infrastructure. Same article reports that one-third of America’s major roads are in poor or mediocre condition [1]. However, portland cement production is recognized with …
Reliability Of Bridge Superstructures In Wisconsin, Azam Nabizadehdarabi
Reliability Of Bridge Superstructures In Wisconsin, Azam Nabizadehdarabi
Theses and Dissertations
ABSTRACT
RELIABILITY OF BRIDGE SUPERSTRUCTURES IN WISCONSIN
by
Azam Nabizadehdarabi
The University of Wisconsin-Milwaukee, 2015
Under the Supervision of Professor Habib Tabatabai
Bridge reliability analyses form the basis of modern bridge design provisions. Such analyses are also used to evaluate bridge condition and assess future maintenance needs. The majority of these reliability assessments are based on evaluating risks associated with the various load effects exceeding their corresponding resistance. However, bridge components such as decks and superstructures typically do not reach the end of their service lives by exceeding the strength limit states (structural failure). Survival analyses, which are commonly used …
Tin Nanoparticles Encapsulated In Hollow Tio2 Spheres As High Performance Anode Materials For Li-Ion Batteries, Xiang Pan
Theses and Dissertations
Tin, an anode material with a high capacity for lithium-ion batteries, has poor cyclic performance because of the high volume expansion upon lithiation. Based on a literature review of the applications of lithium-ion batteries and current research progress of the tin-based anode materials for lithium-ion batteries, we developed a method to synthesize hollow TiO2 spheres with tin nanoparticles anchored on the inner surface of the TiO2 shell. Such a unique tin/TiO2 composite alleviates the volume change of tin–based anode materials in charge-discharge processes. SnCl2·2H2O (Tin (II) chloride dihydrate) and titanium (IV) isopropoxide (TIPT) were used as the Sn source and …
Integrated Li-Ion Ultracapacitor With Lead Acid Battery For Vehicular Start-Stop, Emad Manla
Integrated Li-Ion Ultracapacitor With Lead Acid Battery For Vehicular Start-Stop, Emad Manla
Theses and Dissertations
Advancements in automobile manufacturing aim at improving the driving experience at every level possible. One improvement aspect is increasing gas efficiency via hybridization, which can be achieved by introducing a feature called start-stop. This feature automatically switches the internal combustion engine off when it idles and switches it back on when it is time to resume driving. This application has been proven to reduce the amount of gas consumption and emission of greenhouse effect gases in the atmosphere. However, the repeated cranking of the engine puts a large amount of stress on the lead acid battery required to perform the …
Dynamic Moving Load Identification Using Optimal Sensor Placement And Model Reduction, Paul Augustine
Dynamic Moving Load Identification Using Optimal Sensor Placement And Model Reduction, Paul Augustine
Theses and Dissertations
A structure in service can be subjected to static, dynamic or moving loads. Several situations in practice involve estimation of moving loads which induce vibrations in the structure on which they are applied. An accurate estimation of these loads will ensure product quality and reliability of the final design, and mitigate the cost of structural health monitoring systems. The moving nature of dynamic loads increases the computational difficulty of the problem. One of the types of Inverse Problems involves estimation of the applied load from measured structural response such as strain or accelerations.
Measuring response at a limited number of …
Individual, Occupational And Biomechanical Factors That Affect Slip And Fall Risk From Fixed Ladders, Erika Mae Pliner
Individual, Occupational And Biomechanical Factors That Affect Slip And Fall Risk From Fixed Ladders, Erika Mae Pliner
Theses and Dissertations
Injuries from ladder falls are prevalent and severe. Previous research has examined certain elements of ladder falls such as the ladder base slipping, but few studies have examined the factors that contribute to climbers falling from the ladder, particularly for permanent/fixed ladders. In addition, the biomechanical response to a ladder slip/misstep during ladder climbing and the factors that affect a fall from a ladder are not well understood. This thesis is a two part study that simulated ladder slips and missteps in order to find factors 1) associated with ladder slip risk and 2) that decrease fall severity from a …