Engineering Commons^™

Development And Application Of Biomimetic Electrospun Nanofibers In Total Joint Replacement, Wei Song

Wayne State University Dissertations

Failure of osseointegration (direct anchorage of an implant by bone formation at the bone-implant surface) and implant infection (such as that caused by Staphylococcus aureus, S. aureus) are the two main causes of implant failure and loosening. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. A better understanding of the key factors that influence cell fate decisions at the bone-implant interface is required. Our study is to develop a class of "bone-like" nanofibers (NFs) that promote osseointegration while preventing …

Computational Investigation On The Structural Properties Of Neurofilaments And Their Sidearms, Lakshmi Jayanthi

Wayne State University Dissertations

Neurofilaments (NFs) are class IV intermediate filaments, abundantly found in the large myelinated axons. They are the key determinants of axonal diameter and consequently the nerve conduction properties. On the other hand, abnormal NF accumulation has been the hallmark of debilitating neurodegenerative disorders. NF compaction is also one of the pathological manifestations of traumatic axonal Injury. However, the exact relation between the disorganized NFs and the etiology of the neurodegenerative disorders is yet to be fully understood. NFs are assembled from three subunits: Low (NFL), Medium (NFM) and Heavy (NFH). These subunits are characterized by a common alpha helical rod …

An Analytics Approach To Designing Patient Centered Medical Home, Saeede Ajorlou

Wayne State University Dissertations

Recently the patient centered medical home (PCMH) model has become a popular team based approach focused on delivering more streamlined care to patients. In current practices of medical homes, a clinical based prediction frame is recommended because it can help match the portfolio capacity of PCMH teams with the actual load generated by a set of patients. Without such balances in clinical supply and demand, issues such as excessive under and over utilization of physicians, long waiting time for receiving the appropriate treatment, and non continuity of care will eliminate many advantages of the medical home strategy. In this research, …

Microvortices In Droplets: Generation & Applications, Gopakumar Kamalakshakurup

Wayne State University Dissertations

The emerging field of droplet microfluidics deals with the manipulation of nL-fL droplets encapsulated within an immiscible carrier phase. The droplets are used as reaction containers for biochemical assays, enabling drastic reduction in assay volumes needed for modern life sciences research. To achieve this, basic laboratory processes such as mixing, detection, and metering must be emulated in the droplet format. Three important unit operations relevant to high throughput screening include 1) the concentration of particles and species within droplets, which is necessary for heterogeneous assays; 2) sensing the biochemical contents of a droplet; and 3) the sorting of droplets based …

An Analytics Approach To Reducing Hospital Readmission, Issac Shams

Wayne State University Dissertations

One of the significant sources of waste in the Unites States health care systems is preventable hospital readmission. About 2.3 million Medicare fee-for-service beneficiaries are re-hospitalized within 30 days after discharge which incurs an annual cost of $17 billion. However, it is reported by the Medicare Payment Advisory Commission that about 75% of such readmissions can and should be avoided because they are the results of factors such as poor planning for follow up care transitions, inadequate communication of discharge instructions, and failure to reconcile and coordinate medications. Hence, reducing unnecessary rehospitalization through care transition and systems engineering principles has …

Elastic Stability Of Flexural Members In Civil Engineering Design, Alexander Lamb

Wayne State University Dissertations

The elastic lateral torsional stability of flexural members is studied. The effects of moment distribution between supports and load height with respect to shear center are examined using numerical and analytical methods. From these methods, independent moment and shear factors are developed for a range of load types and load heights. A code comparison is performed comparing numeric results with those produced by AISC 360 to illustrate situations where issues occur in terms of strength prediction. A reliability analysis is performed from this data to quantify the difference in terms of the reliability index using a Monte Carlo Simulation. The …

Dendrimer Based Nanotherapeutics For Ocular Drug Delivery, Siva Pramodh Kambhampati

Wayne State University Dissertations

PAMAM dendrimers are a class of well-defined, hyperbranched polymeric nanocarriers that are being investigated for ocular drug and gene delivery. Their favorable properties such as small size, multivalency and water solubility can provide significant opportunities for many biologically unstable drugs and allows potentially favorable ocular biodistribution. This work exploits hydroxyl terminated dendrimers (G4-OH) as drug/gene delivery vehicles that can target retinal microglia and pigment epithelium via systemic delivery with improved efficacy at much lower concentrations without any side effects.

Two different drugs Triamcinolone acetonide (TA) and N-Acetyl Cysteine (NAC) conjugated to G4-OH dendrimers showed tailorable sustained release in physiological relevant …

Study Of Tin-Based Electrodes And Ionic Liquid Electrolytes For Energy Storage Materials, Mahbuba Ara

Wayne State University Dissertations

Due to rapid increase in energy demand, modern society necessitates to develop high power, light-weight, and more economical energy storage systems. Rechargeable Li-ion batteries and Li-oxygen batteries have become the most promising energy devices in terms of energy and power densities. Diverse research on these battery components is being carried out by researchers worldwide to improve power density to meet the future requirements. The possible routes to improving power density of Li-ion as well as Li-oxygen batteries is to use nanostructured, hybrid electrode materials since they can significantly enhance kinetics of electrochemical reactions; and ion-conducting, low volatile electrolytes since they …

Nonlinear Modeling Using Neural Networks For Trading The Soybean Complex, Phoebe S. Wiles, David Lee Enke

Engineering Management and Systems Engineering Faculty Research & Creative Works

Recently, there has been a spike in the prices and popularity of commodities. On a macroeconomic level, developing countries are increasing production; while on a microeconomic level, speculative traders are becoming more involved in the market. Agricultural products have a diverse array of factors that can affect the price (i.e. political, government, population, weather, supply and demand). Commodity prices can suffer from extreme volatility in the short term, changing as much as 50% in one year. This research uses the soybean crush spread as a model. The soybean complex adds an interesting component as the underlying soybean product can be …

Introduction To Special Issue Of Journal Of Defense Modeling And Simulation: Novel Approaches To Defense And Military Modeling And Simulation, Scott D. Snyder, James M. Taylor Jr.

Peter Kiewit Institute: Faculty Publications

Developing solutions to complex problems in government and industry is a daunting task that often requires tremendous investment in time and resources to solve. Modeling and simulation (M&S) has incredible potential to streamline development and cut costs by conducting virtual experiments that give insight into performance under various test conditions. As many program managers in the federal acquisition process can attest, realistic testing of live equipment in an operational environment can be some of the most expensive parts of a development program. M&S can provide insight into mission success of yetto- bedesigned systems without the need to actually build and …

Simple Multi-Attribute Rating Technique For Renewable Energy Deployment Decisions (Smart Redd), James M. Taylor Jr., Betty Love

Peter Kiewit Institute: Faculty Publications

In the effort to provide electrical power service and the sustaining fuel required to run generators at forward-deployed bases in Afghanistan and Iraq over more than 10 years, the United States military spent billions of dollars and a paid a heavy toll in terms of human casualties. The green energy linear program for optimizing deployments (GELPOD) proof-of-concept model showed that a linear program could be used to optimize combat deployment of energy generation systems to minimize cost and casualties. Results indicated that reduction in both cost and casualties for renewable energy sources was highly dependent on fuel cost and deployment …

An Assessment Of Flow Regime Maps And A Numerical Heat Transfer Correlation For The Stratified/Annular Regime Of Shear-Driven Internal Condensing Flows, Fnu Nikhil Shankar

Dissertations, Master's Theses and Master's Reports - Open

Several modern-day cooling applications require the incorporation of mini/micro-channel shear-driven flow condensers. There are several design challenges that need to be overcome in order to meet those requirements.

The difficulty in developing effective design tools for shear-driven flow condensers is exacerbated due to the lack of a bridge between the physics-based modelling of condensing flows and the current, popular approach based on semi-empirical heat transfer correlations. One of the primary contributors of this disconnect is a lack of understanding caused by the fact that typical heat transfer correlations eliminate the dependence of the heat transfer coefficient on the method of …

An Investigation Of Variable Valve Timing Effects On Hcci Engine Performance, Hrishikesh Abhay Saigaonkar

Dissertations, Master's Theses and Master's Reports - Open

The Homogeneous Charge Compression Ignition (HCCI) engine is a promising combustion concept for reducing NO_x and particulate matter (PM) emissions and providing a high thermal efficiency in internal combustion engines. This concept though has limitations in the areas of combustion control and achieving stable combustion at high loads. For HCCI to be a viable option for on-road vehicles, further understanding of its combustion phenomenon and its control are essential. Thus, this thesis has a focus on both the experimental setup of an HCCI engine at Michigan Technological University (MTU) and also developing a physical numerical simulation model called the …

Test-Analysis Model Correlation And Calibration Of A Multi-Component Plastic Part, Steven P. Carter

Dissertations, Master's Theses and Master's Reports - Open

The goal of this project is to learn the necessary steps to create a finite element model, which can accurately predict the dynamic response of a Kohler Engines Heavy Duty Air Cleaner (HDAC). This air cleaner is composed of three glass reinforced plastic components and two air filters. Several uncertainties arose in the finite element (FE) model due to the HDAC’s component material properties and assembly conditions. To help understand and mitigate these uncertainties, analytical and experimental modal models were created concurrently to perform a model correlation and calibration. Over the course of the project simple and practical methods were …

Reconciling Function- And Affordance-Based Design, Benjamin T. Ciavola

Dissertations, Master's Theses and Master's Reports - Open

Traditional engineering design methods are based on Simon's (1969) use of the concept function, and as such collectively suffer from both theoretical and practical shortcomings. Researchers in the field of affordance-based design have borrowed from ecological psychology in an attempt to address the blind spots of function-based design, developing alternative ontologies and design processes. This dissertation presents function and affordance theory as both compatible and complimentary. We first present a hybrid approach to design for technology change, followed by a reconciliation and integration of function and affordance ontologies for use in design. We explore the integration of a standard function-based …

Design, Synthesis And Applications Of Fluorescent And Electrochemical Probes, Giri K. Vegesna

Dissertations, Master's Theses and Master's Reports - Open

“Seeing is believing” the proverb well suits for fluorescent imaging probes. Since we can selectively and sensitively visualize small biomolecules, organelles such as lysosomes, neutral molecules, metal ions, anions through cellular imaging, fluorescent probes can help shed light on the physiological and pathophysiological path ways. Since these biomolecules are produced in low concentrations in the biochemical pathways, general analytical techniques either fail to detect or are not sensitive enough to differentiate the relative concentrations. During my Ph.D. study, I exploited synthetic organic techniques to design and synthesize fluorescent probes with desirable properties such as high water solubility, high sensitivity and …

Phase I Assessment Of Guardrail Length-Of-Need, Francisco Daniel B. Albuquerque, Cody S. Stolle, Dean L. Sicking, Ronald K. Faller, Karla A. Lechtenberg

Mid-America Transportation Center: Final Reports and Technical Briefs

Report No. TRP-03-284-14

Roadside Grading Guidance - Phase Ii, Kevin D. Schrum, Francisco D. B. Albuquerque, Dean L. Sicking, Ronald K. Faller, John D. Reid

Mid-America Transportation Center: Final Reports and Technical Briefs

Phase I of this project relied on assumptions surrounding crash data from the state of Ohio in 2000. The number of fatal and severe crashes in that year was significantly lower than average. As a result, the conclusions were indefinite. Phase II was carried out using crash data from the state of Ohio over seven years. The increased pool of data removed the need for many of the underlying assumptions used in Phase I and provided a solid foundation of conclusions and recommendations.

The number of fatal and severe crashes that occurred on each slope and height for each functional …

Description Logics, Adila Krisnadhi, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Description logics (DLs) is a family of knowledge representation (KR) languages which represent knowledge in a domain of interest using formal, logic-based semantics through knowledge bases (KBs) containing general assertions of describing relevant concepts - hence, the term description - and specific assertions about individuals and relationships among them.

Ontology Design Patterns For Ocean Science Data Discovery, Pascal Hitzler

Computer Science and Engineering Faculty Publications

No abstract provided.

Day-Of-Discharge Planning At Acute Care Hospitals, Kylie M. Bertsch

Browse all Theses and Dissertations

Hospitals provide a complex array of services to patient populations with highly variable conditions, needs, and preferences. These services are delivered with limited resources, and therefore, the synchronization of patient flow between various units in the hospital is essential for minimizing patient delay and congestion. Unfortunately, patient flow optimization is a topic in its research infancy, and, in current practice, hospitals struggle with the numerous ramifications of delays in care provision and increased costs. Emergency Department (ED) crowding and boarding have become a topic of increased interest as the ED becomes an increasingly popular entry point to acute care hospitals. …

Hispanic Construction Workers And Assertiveness Training, Pramen Shrestha, Nancy Menzel

Nursing Faculty Research

BACKGROUND: Hispanic (Latino) construction workers experience disparities in occupational death and injury rates in the United States. The cultural value of respect for those in authority may hinder these workers from requesting safe working conditions from supervisors.

OBJECTIVE: To evaluate whether Hispanic construction workers in Las Vegas, Nevada found assertiveness training more useful than non-Hispanic trainees and whether or not they practiced this behavior at work after the training.

METHODS: An assertiveness training simulation was part of fall prevention classes offered to area construction workers. Eight weeks after the training, participants were interviewed by telephone about class topics they found …

Dtaf Dye Concentrations Commonly Used To Measure Microscale Deformations In Biological Tissues Alter Tissue Mechanics., Spencer E Szczesny, Rachel S. Riley, Dawn M Elliott

Henry M. Rowan College of Engineering Departmental Research

Identification of the deformation mechanisms and specific components underlying the mechanical function of biological tissues requires mechanical testing at multiple levels within the tissue hierarchical structure. Dichlorotriazinylaminofluorescein (DTAF) is a fluorescent dye that is used to visualize microscale deformations of the extracellular matrix in soft collagenous tissues. However, the DTAF concentrations commonly employed in previous multiscale experiments (≥2000 µg/ml) may alter tissue mechanics. The objective of this study was to determine whether DTAF affects tendon fascicle mechanics and if a concentration threshold exists below which any observed effects are negligible. This information is valuable for guiding the continued use of …

The Effect Of Types Of Alcohol Upon A Support Of Zieglernatta Catalyst To Catalytic Performance, Molecular Weight And Comonomer Composition Distribution, Kanokporn Sinchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the effect of types of alcohol upon a support of Ziegler-Natta catalyst on ethylene polymerization and ethylene/ 1-hexene copolymerization. Alcohols are the Lewis base, which are used during catalyst preparation. The types of alcohol were divided into two systems. First system is the using ethanol as a Lewis base. Second system is the use of a mixture of ethanol with other alcohols such as isopropanol, 1-butanol, 2-butanol, isobutanol, 1-hexanol, 2-hexanol and cyclohexanol. The results showed that the mixture of alcohols did not change the morphology of catalyst. Moreover, these catalysts exhibited the higher activity than the catalyst …

Graduate School Of Engineering And Management Catalog 2014-2015, Graduate School Of Engineering And Management, Air Force Institute Of Technology

AFIT Documents

The Graduate Catalog represents the offerings, programs, and requirements in effect at the time of publication.

เสถียรภาพแบบไม่ระบายน้ำของกำแพงกันดินเสาเข็มในดินเหนียว, กานต์ ถีระวงษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์นี้เสนอการศึกษาเสถียรภาพแบบไม่ระบายของกำแพงกันดินเสาเข็มสำหรับงานขุดในดินเหนียว ด้วยระเบียบวิธีไฟไนต์อิลิเมนต์สองและสามมิติ กำแพงกันดินและดินเหนียวถูกจำลองเป็นชิ้นส่วนแบบปริมาตร ชิ้นส่วนเชื่อมต่อระหว่างดินและโครงสร้างถูกนำมาใช้ที่ผิวสัมผัสระหว่างกำแพงและดินโดยรอบ ดินเหนียวถูกแบ่งเป็นสองชั้น คือ ดินเหนียวชั้นบนจะมีความลึกจากผิวดินจนถึงความลึกงานขุด และดินเหนียวชั้นล่างจะอยู่ตั้งแต่ความลึกงานขุดลงไป การศึกษานี้พิจารณาลักษณะการค้ำยันกำแพงในแนวระดับสี่ประเภทคือ กำแพงไม่มีการค้ำยัน กำแพงมีการค้ำยันที่จุดบนสุดของกำแพง กำแพงมีการค้ำยันที่จุดบนสุด และจุดกึ่งกลางที่ระยะครึ่งหนึ่งของความลึกงานขุดจากจุดบนสุดของกำแพง และกำแพงมีการค้ำยันต่อเนื่องตลอดฝั่งด้านเสาเข็มที่ขุดดินออก กำแพงกันดินเสาเข็มถูกจำลองเป็นวัสดุอิลาสติก ดินเหนียวถูกจำลองด้วยวัสดุมอห์ร-คูลอมบ์ที่สภาวะไม่ระบายน้ำ การจำลองสภาพวิบัติของระเบียบวิธีไฟไนต์อิลิเมนต์ใช้หลักการลดทอนกำลัง ผลการศึกษาถูกเสนอเป็นแผนภูมิออกแบบของตัวเลขเสถียรภาพที่สัมพันธ์กับพารามิเตอร์ไร้มิติของขนาดรูปร่างของกำแพงกันดิน งานขุด และคุณสมบัติดิน การเปรียบเทียบผลเฉลยกรณีกำแพงมีการค้ำยันต่อเนื่องแบบสองมิติของการศึกษานี้กับผลเฉลยจากวิธีวิเคราะห์ในอดีตแสดงความสอดคล้องกัน นอกจากนั้นยังได้เสนอสมการผลเฉลยเพื่อความสะดวกในการใช้งานผลการศึกษาจากแผนภูมิออกแบบ

Controlled De-Cross-Linking And Disentanglement Of Feather Keratin For Fiber Preparation Via A Novel Process, Helan Xu, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pure protein fibers were fabricated from chicken feathers via a potentially green process. In the last several decades, efforts have been made to produce keratin-based industrial products, especially fibers. However, the methods of producing keratin fibers directly from chicken feathers could not be repeated. In this research, protein fibers from chicken feathers were developed using chemicals that could be either derived from renewable resources or facilely recycled. Backbones of keratin were preserved after cleavage of disulfide bonds using cysteine. Sodium dodecyl sulfate (SDS) was applied to dissolve keratin for spinning. Increasing SDS concentration intensified the ordered conformation of keratin, first …

Fiber-Optic Temperature Sensor Using A Fabry–Pérot Cavity Filled With Gas Of Variable Pressure, Yujie Lu, Ming Han, Jiajun Tian

Department of Electrical and Computer Engineering: Faculty Publications

We report a high-temperature fiber-optic sensor based on measuring the spectral fringes of a Fabry–Pérot (FP) cavity on a microstructure fiber (MF) when the gas pressure in the cavity is varied through the holes in the MF. Theoretical analysis shows that the absolute temperature can be deduced from the slope of the spectral shift versus pressure curve, which requires no calibration and is insensitive to the FP cavity length variations. For demonstration, we fabricated a miniature sensor whose FP cavity is formed by sandwiching a fuse-silica tube between a side-hole MF and a solid-core fiber. Using the holes in the …

An Interconnection And Damping Assignment Passivity-Based Controller For A Dc–Dc Boost Converter With A Constant Power Load, Jianwu Zeng, Zhe Zhang, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes an adaptive interconnection and damping assignment (IDA) passivity-based controller (PBC) with a complementary proportional integral (PI) controller for dc–dc boost converters with constant power loads (CPLs). The plant is modeled as a port-controlled Hamiltonian system (PCHS). A virtual circuit that interprets the parameters of the PCHS is then derived to determine the parameters of the IDA-PBC for the system to work in the underdamping, critical-damping, and overdamping modes. Moreover, a complementary PI controller is designed to eliminate the steady-state output voltage error of the IDA-PBC caused by the load variation. Simulation studies are carried out inMATLAB/Simulink to …

An Effective Heat Propagation Path-Based Online Adaptive Thermal Model For Igbt Modules, Ze Wang, Wei Qiao, Bo Tian, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

The information of junction temperature is crucial for operation management of IGBT modules. In practice, junction temperature is typically estimated by using an electrothermal model. IGBT modules are subject to various aging processes during operation, some of which, e.g. substrate solder crack, changes the thermal impedance of an IGBT module. However, in the literature little work has included the aging effects into online thermal behavior modeling of IGBT modules. This paper proposes an Effective Heat Propagation Path (EHPP)-based online adaptive thermal model for IGBT modules, where the EHPP is proposed to quantify the impact of substrate solder cracks on the …