Engineering Commons^™

Rheology Of Cross-Linked Polymers And Polymer Foams: Theory And Experimental Results, John Herman

Wayne State University Dissertations

Typical polymers have a time-dependent response to loading which results in stress relaxation or creep. Models using springs/dashpots or Volterra integrals are capable of predicting the material response, but place little or no emphasis on the reasoning behind the response. This research proposes a microscopic reasoning behind polymer chain movement, while developing a model to predict the creep and stress relaxation of a polymer foam. Based on the theorized slip/stick of polymer chains as they slide past each other, this model successfully predicts the behavior of a PMI polymer foam under tensile loads. This model lends insights into polymer microscopic …

Specialized Inter-Particle Interaction Lbm For Patterned Superhydrophobic Surfaces, Amal Saeed Yagub

Wayne State University Dissertations

SPECIALIZED INTER-PARTICLE INTERACTION LBM FOR PATTERNED SUPERHYDROPHOBIC SURFACES

by

AMAL S. YAGUB

ABSTRACT:

Superhydrophobic surface characteristics are important in many industrial applications, ranging from the textile to the military. It was observed that surfaces fabricated with nano/micro roughness can manipulate the droplet contact angle, thus providing an opportunity to control the droplet wetting characteristics. The Shan and Chen (SC) lattice Boltzmann model (LBM) is a good numerical tool, which holds strong potentials to qualify for simulating droplets wettability. This is due to its realistic nature of droplet contact angle (CA) prediction on flat smooth surfaces. But SC-LBM was not able …

Development Of A Human Heart Rate And Skin Temeprature Monitoring System, Giribabu Sinnapolu

Wayne State University Theses

Continuous heart rate monitors (CHRM) can give unique insights into a person's physiological and psychological state; however, existing CHRMs are not suitable for continuous monitoring because they do not provide beat-to-beat accuracy and comfort needed for all-day use. Our group is currently developing a miniature earlobe mounted CHRM system which is both comfortable and provides beat-to-beat accuracy, based on a miniature heart rate sensing technology developed previously in our lab. The objective of this thesis is to design low power system firmware to perform key tasks: i) acquire heart rate and skin temperature data from wearable sensors; ii) signal process …

Novel Pulsatile Cardiac Assist Pump, Lakshmi Mohanadas

Wayne State University Theses

The project involve the research and development of a pulsatile, complex or continuous flow in biological and non-biological systems implantable heart assist pump. Specifically as a 20% cardiac assist for persons from congestive heart failure and other cardiac abnormalities. The pulsatile cardiac assist pump would provide upto 20% of the blood pumping process from the venous supply to the arterial supply. Current pumps are largely complete bypass pumps or large volume pumps that produce significant long term blood cell damage resulting in thrombosis. Most are not pulsatile which offers a significant physiological advantage. The pump under development is designed to …

Programmable Dna Delivery To Cells Using Bioreducible Layer-By-Layer (Lbl) Polyelectrolyte Thin Films, Maria Muniz

Wayne State University Theses

Bioreducible, layer-by-layer (LbL) polyelectrolyte films show great promise for use in biomedical implant and gene-delivery applications. These nanometer-scale thin films can easily be coated onto a variety of implantable surfaces or devices. To achieve proof of concept, HEK-293, NIH/3T3, RAW, and MC3T3 cells were transfected using plasmid DNA with the green fluorescent protein reporter gene (GFP-DNA). In order to optimize transfection, a number of polyelectrolytes and biological components were systematically incorporated into the two similar basic LbL structures. Based on our previous degradation assays, it is shown that cellular interactions in vitro can break down the layers of the thin …

Evaluation Of An Architectural-Level Approach For Finding Security Vulnerabilities, Mohammad Anamul Haque

Wayne State University Theses

The cost of security vulnerabilities of a software system is high. As a result,

many techniques have been developed to find the vulnerabilities at development time. Of particular interest are static analysis techniques that can consider all possible executions of a system. But, static analysis can suffer from a large number of false positives.

A recently developed approach, Scoria, is a semi-automated static analysis that requires security architects to annotate the code, typecheck the annotations, extract a hierarchical object graph and write constraints in order to find security vulnerabilities in a system.

This thesis evaluates Scoria on three systems (sizes …

Visibility And Confidence Estimation Of An Onboard-Camera Image For An Intelligent Vehicle, Minglei Huang

Wayne State University Theses

More and more drivers nowadays enjoy the convenience brought by advanced driver assistances system (ADAS) including collision detection, lane keeping and ACC. However, many assistant functions are still constrained by weather and terrain. In the way towards automated driving, the need of an automatic condition detector is inevitable, since many solutions only work for certain conditions. When it comes to camera, which is most commonly used tool in lane detection, obstacle detection, visibility estimation is one of such important parameters we need to analyze.

Although many papers have proposed their own ways to estimate visibility range, there is little research …

The Design And Vlsi Implementation Of Digital Arithmatic Processors - A Case Study Of A Generalized Pipeline Cellular Array, Yudi Xie

Wayne State University Theses

A generalized pipeline array appeared in IEEE transaction in 1974. The array appeared in a few textbooks on computer arithmetic. From time to time, a number of papers appeared which reflected the modifications of this array. The objective of this thesis is to present the design and VLSI implementation of this array, which can add, subtract, multiply, divide, square and square root of binary numbers. In this thesis, we suggest a step-by-step procedure by which the design can be sent to MOSIS and to get the fabricated chip back. The array has been extended from 5 rows to 7 rows …

A Framework To Improve A Nation's Competitiveness Through Quality Awards And Performance Improvement Tools, Amr Alamri

Wayne State University Dissertations

Each country, represented by its government, aims to serve its citizens better. This is achieved by better utilization of resources and higher productivity. The ability to do so will lead to a competitive nation. Recently, countries were able to compare themselves in terms of competitiveness using international indexes and references. These references gave countries a benchmark to know where they exist compared to other nations. They help governments to understand their strengths and weaknesses within the competitiveness components. However, nations differ in the actions which are to be taken in order to improve their competitiveness. Governments establish and regulate many …

Lean Thinking For Lead-Time Reduction And Efficient Knowledge Creation In Product Development, Satish Kumar Tyagi

Wayne State University Dissertations

There are many distinct differences between manufacturing process and Product Development (PD) process, so lean tools have to be customized to deliver results in the later domain. The main focus of this dissertation is to extend them to manage and improve the PD process in order to develop the product faster while improving or at least maintaining the level of performance and quality. For aforesaid purpose, value stream mapping (VSM) method is used to explore the wastes, inefficiencies, non-valued added steps in a single, definable process out of complete PD process. Besides numerous intangible benefits, VSM framework will help the …

Modeling And Optimization Of Non-Profit Hospital Call Centers With Service Blending, Yanli Zhao

Wayne State University Dissertations

This dissertation focuses on the operations problems in non-profit hospital call centers with inbound and outbound calls service blending.

First, the routing policy for inbound and outbound calls is considered. The objective is to improve the system utilization under constraints of service quality and operators' quantity. A collection of practical staffing assignment methods, separating and mixing staffing policy are evaluated. Erlang C queuing model is used to decide the minimum number of operators required by inbound calls. Theoretical analysis and numerical experiments illustrate that through dynamically assigning the inbound and outbound calls to operators under optimal threshold policy, mixing staffing …

Reliability Analysis And Optimal Maintenance Planning For Repairable Multi-Component Systems Subject To Dependent Competing Risks, Nailong Zhang

Wayne State University Dissertations

Modern engineering systems generally consist of multiple components that interact in a complex manner. Reliability analysis of multi-component repairable systems plays a critical role for system safety and cost reduction. Establishing reliability models and scheduling optimal maintenance plans for multi-component repairable systems, however, is still a big challenge when considering the dependency of component failures. Existing models commonly make prior assumptions, without statistical verification, as to whether different component failures are independent or not. In this dissertation, data-driven systematic methodologies to characterize component failure dependency of complex systems are proposed. In CHAPTER 2, a parametric reliability model is proposed to …

Development Of Scaffold Architectures And Heterotypic Cell Systems For Hepatocyte Transplantation, Dalia Alzebdeh

Wayne State University Dissertations

In vitro assembly of functional liver tissue is needed to enable the transplantation of tissue-engineered livers. In addition, there is an increasing demand for in vitro models that replicate complex events occurring in the liver. However, tissue engineering of sizable implantable liver systems is currently limited by the difficulty of assembling three dimensional hepatocyte cultures of a useful size, while maintaining full cell viability, an issue which is closely related to the high metabolic rate of hepatocytes. In this study, we first compared two designs of highly porous chitosan-heparin scaffolds seeded with hepatocytes in dynamic perfusion bioreactor systems. The aim …

A Prediction Modeling Framework For Noisy Welding Quality Data, Junheung Park

Wayne State University Dissertations

Numerous and various research projects have been conducted to utilize historical manufacturing process data in product design. These manufacturing process data often contain data inconsistencies, and it causes challenges in extracting useful information from the data. In resistance spot welding (RSW), data inconsistency is a well-known issue. In general, such inconsistent data are treated as noise data and removed from the original dataset before conducting analyses or constructing prediction models. This may not be desirable for every design and manufacturing applications since every data can contain important information to further explain the process. In this research, we propose a prediction …

A Biomechanical Assessment Of Canine Body Armor, Sarah Stojsih

Wayne State University Dissertations

The purpose of this research was to establish a biomechanical assessment of canine body armor with a primary focus on civilian law enforcement canines. The specific aims included: 1) the compilation of canine casualty data to determine commonly reported causes of death/euthanasia while in service for civilian law enforcement canines, 2) the evaluation of the biomechanical response of the canine related to a behind armor blunt impact, 3) the identification of an injury criterion that will best predict canine thoracic injury as a result of behind armor blunt trauma, 4) correlation of the behind armor blunt trauma response to the …

Development Of High Strength High Toughness Third Generation Advanced High Strength Steels., Codrick John Martis

Wayne State University Dissertations

Third generation advanced high strength steels (AHSS's) are emerging as very important engineering materials for structural applications. These steels have high specific strength and thus will contribute significantly to weight reduction in automotive and other structural component. In this investigation two such low carbon low alloy steels (LCLA) with high silicon content (1.6-2wt %) has been developed. These two steel alloys were subjected to single step and two step austempering in the temperature range of 260-399oC to obtain desired microstructures and mechanical properties. Austempering heat treatment was carried out for 2 hours in a molten salt bath. The microstructures were …

Benefit-Cost Analysis Of Using Class F Fly Ash-Based Green Cement In Masonry Units, Khaled Shwekat

Wayne State University Dissertations

ABSTRACT

BENEFIT-COST ANALYSIS OF USING CLASS F FLY ASH-BASED GREEN CEMENT IN MASONRY UNITS

by

KHALED SHWEKAT

August 2015

Advisor: Dr. Hwai-Chung Wu

Major: Civil engineering

Degree: Doctor of Philosophy

The Portland cement concrete is the most popularly used building material around the world. However, there are major drawbacks associated with Portland cement, such as the emission of greenhouse gasses and high-energy consumption from cement production. Therefore, Portland cement concrete has many disadvantages that can only be overcome by being replaced with new materials such as fly ash-based green cement. Recycling fly ash and using it to replace cement has …

Analysis Of Queue Characteristics At Signalized Intersections Near Highway-Railroad Grade Crossing, Amna Chaudhry

Wayne State University Dissertations

Analysis of traffic queues at signalized intersections which are in close proximity to highway- railroad grade crossings is of primary importance for determining if the normal signal operation needs to be preempted for railroad operations by providing a special signal mode for safe clearance of the queued vehicles from the tracks before the train arrival, and prohibiting any conflicting traffic movements towards the crossing. Such queuing analysis becomes even more critical where direct observations of traffic queues are not possible or where the assessment is needed for a future location. Inadequate estimation of queues from signalized intersections to the nearby …

Face Sheet/Core Debonding In Sandwich Composites Under Static And Fatigue Loading, Manjinder Singh Warriach

Wayne State University Dissertations

Delamination growth due to face sheet/core debonding is a major concern due to its inherent weakness in sandwich composites which can be exacerbated due to the presence of flaws. In this research work The primary objective of this research was to characterize the delamination crack growth behavior in E-glass face sheet/polyurethane foam core sandwich composite with pre-existing initial delamination crack at a face sheet/core interface under static and fatigue for mode I and mixed mode loading. For mode I static loading two types of delamination experiments, namely T-peel test and wedge test were implemented to evaluate fracture toughness in polyurethane …

Helmholtz Equation Least Squares Based Near-Field Acoustic Holography With Laser, Wu Zhu

Wayne State University Dissertations

This dissertation presents the HELS based NAH with laser and use normal surface velocity as input in near-field acoustic holography. The conventional HELS based NAH uses acoustic pressure as input to reconstruct sound field quantities, while this modified HELS based NAH with laser utilizes the normal surface velocities measured by LDV to reconstruct the acoustic quantities at interested positions. Theoretical principles of the HELS based NAH with laser have been fully developed and the method has been verified in theoretical perspective. Two theoretical examples verify that HELS based NAH with laser can obtain exactly the same results as analytic solution. …

Accurate And Efficient Reliability Analysis Of Complex Structural Engineering Problems, Kapil Dilip Patki

Wayne State University Dissertations

ABSTRACT

ACCURATE AND EFFIFICIENT RELIABILITY ANALYSIS OF COMPLEX STRUCTURAL ENGINEERING PROBLEMS

by

KAPIL DILIP PATKI

December 2015

Advisor: Dr. Christopher Douglas Eamon

Major: Civil Engineering

Degree: Doctor of Philosophy

Accurate probabilistic analysis of complex engineering problems with reasonable computational effort is a popular area of research in structural reliability analysis. For probabilistically complex problems such as those involving nonlinear FE analysis; traditional simulation methods often require unfeasibly great computational effort, while low-cost reliability index approaches may lack sufficient accuracy. This dissertation report addresses this issue by developing a simulation-based method referred to as Advanced Failure Sampling (FS).

In this research, …

Analysis And Suppression Of Engine Hood Vibrations Under Random Road Excitations, Hooman Farrokhzadeh

Wayne State University Theses

Vehicle designs and developments must meet safety legislations along with market demands. Safety regulations are mainly concerned with how a vehicle body performs in crashes, during which pedestrian collision is the one of the most important issues. When a vehicle strikes a pedestrian, its engine hood will most likely hit the head of the pedestrian, causing serious injuries. To reduce the severity of the injuries, along with market demands to improve vehicle fuel economy and performance, engineers have considered the design solution of reduction of the vehicle hood thickness (and hence its weight) and the use of advanced light materials. …

Statistical Approach To Design For Fall Prevention In Construction, Kyunghwan Kim

Wayne State University Theses

During the past decades, the construction industry has been considered as one of the most vulnerable field to work-related injuries and fatalities, and fall accidents are the leading causes accounting for about one-third of the total fatal injuries happened in construction. Furthermore, more than 30% of fall fatal cases occurred in the projects under $ 300K in Korea where construction workers' safety and health are not usually considered as top priorities because the contractors, who are normally small sized construction firms or self-employed, do not have safety budget to deal with construction workers' safety.

In this respect, this study focused …

Assessment Of Temporal And Spatial Alterations In Spinal Glial Reactivityand The Extent Of Cervical Spinal Axonal Injury In The Rat After Blast Overpressure, Heena S. Purkait

Wayne State University Theses

Blast induced neurotrauma (BINT) is the signature wound of veterans returning from various military operations. A substantial percentage of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF) veterans have reported to experience ongoing or new pain following their military service. Head (58%) and back (55%) have been the high prevailing locations of pain in these returning OIF and OEF veterans and the underlying pathomechanism of these conditions is yet to be understood. In the context of blast overpressure induced pathological changes, the fundamental question that still needs to be addressed is whether there are any underlying cellular injury changes the …

Advancement And Validation Of A Plug-In Hybrid Electric Vehicle Model Utilizing Experimental Data From Vehicle Testing, Kevin Lloyd Snyder

Wayne State University Theses

The objective of the research into modeling and simulation was to provide an iterative improvement to the Wayne State EcoCAR 2 team's math-based design tools for use in evaluating different outcomes based on hybrid powertrain architecture tweaks, controls code development and testing. This thesis includes the results of the team's work in the EcoCAR 2 competition for university student teams to create and test a plug-in hybrid electric vehicle for reducing petroleum oil consumption, pollutant emissions, and Green House Gas (GHG) emissions.

Plant model validations and advancements brought the vehicle plant model directionally closer to the actual vehicle's experimental data …

Fabrication And Characterization Of A Robust, Field- Deployable, Optical Sensor Designed To Detect Particles In Oils., Navya Pandreka

Wayne State University Theses

Some types of bacteria and fungus can use iron or non-ferrous metals for their metabolic process. Sulfate-reducing bacteria can corrode pipes in the oil industry and high-end machinery. Both aerobic and anaerobic bacteria often degrade fuel quality and cause fuel system corrosion or alter the chemical properties of the fluid. This causes significant economic damage and safety concerns. Therefore, there is a need for a system to continuously monitor fuel or lubricant oil for the presence of bacteria and fungus.

The main goal of this project was to develop a sensor that can detect bacteria and other ferrous and non-ferrous …

Developing An Automated Forecasting Framework For Predicting Operation Room Block Time, Azad Sadr Haghighi

Wayne State University Theses

Operating rooms are the most important part of the hospitals, since they have highest influence on financial state of the hospital. Because of high uncertainty in surgery cases demands and their durations, the scheduling of the surgeries becomes a very challenging and critical issue in hospitals. One of the most common approaches to overcome this uncertainty is applying block times which is the time intervals allocated to surgery groups in the hospital. Assigning sufficient amount of the time to each block, is very important, since overestimating lead to wasting resources and on the other hand underestimation causes the overtime staffing …

First-Principles Point Defect Models In Zr7ni10 And Zr2ni7 Binary Intermetallic Compounds And Their Implications In Nickel-Metal Hydride Batteries, Diana Felicia Wong

Wayne State University Theses

Zr-Ni-based alloys as nickel-metal hydride battery anode materials offer low-cost, flexible and tunable battery performance. Zr7Ni10 is an important secondary phase found in multi-phased AB2 Laves-phase-based metal hydride alloys, and the synergetic effect between the Zr-Ni and the Laves phases allows access to the high hydrogen storage of the Zr-Ni phases despite the lower absorption/desorption kinetics. Zr7Ni10 displays a small solubility window for Zr-rich compositions, while Zr2Ni7, with no solubility window, shows poor capacity with good kinetics. Stability of point defects within the crystal structure allows Zr7Ni10 to maintain the same structure at off-stoichiometric compositions, thus it is theorized that …

A Customer Choice Modeling Framework For Assortment Planning Of Configurable Products In Automotive Industry, Farah Dubaisi

Wayne State University Theses

Due to the increased competition in the auto industry, proliferation of the vehicle models and increased customer need for choice and customization, it has become more critical than ever to offer a variety of features and customization flexibility while at the same time restraining and, even better, cutting down the costs. Product complexity, in the automotive industry, can be measured by the size of the assortment offered, i.e., set of vehicle configurations a customer can choose from (e.g., for a given model of a brand). While complexity fosters growth with increased alignment of product characteristics and customer needs, it results …

Quantitative Brain Electrical Activity In The Initial Screening Of Mild Traumatic Brain Injuries After Blast, Chengpeng Zhou

Wayne State University Theses

ABSTRACT

QUANTITATIVE BRAIN ELECTRICAL ACTIVITY IN THE INITIAL SCREENING OF MILD TRAUMATIC BRAIN INJURIES AFTER BLAST

by

CHENGPENG ZHOU

August 2015

Advisor: Dr. John Michael Cavanaugh, Dr. Chaoyang Chen

Major: Biomedical Engineering

Degree: Master of Science

Objective: Quantitative electroencephalography (QEEG) has been reported to be sensitive in the diagnosis and measurement of mild traumatic brain injury (mTBI) in civilian setting and thus may be a promising tool in individuals who have been exposed to blast forces. Using a swine model, this study investigated EEG changes early after blast exposure. The purpose was to determine if QEEG can detect brain activity …