Engineering Commons^™

Predicting And Reducing Warranty Costs By Considering Customer Expectation And Product Performance, Naresh Kumar Sharma

Doctoral Dissertations

"This dissertation develops from quality loss function to warranty loss function in which customer expectation is also considered to be a variable. First, Taguchi's quality loss function for the larger-the-better case, which is different from the smaller-the better and nominal-the-best cases, has been assimilated into the other two by introducing a term called the target-mean ratio. Further topics addressed include the implications of a finite target on the classification of LTB characteristics, a new concept of a "Complementary Characteristic", operating window, complexity, and SN ratio based on complexity. A warranty is a buyer's confidence owing to the seller's assurance to …

Unsteady Flow And Heat Transfer In Periodic Complex Geometries For The Transitional Flow Regime, Li-Kwen Chen

Doctoral Dissertations

"Diesel engines are facing significant challenges with upcoming changes in emissions standards. In general, meeting the increased emission standards will require a larger fraction of the engine heat rejection to occur in the vehicle cooling system. For certain applications, the surface geometry must also be such that it resists particulate fouling, precluding common interrupted surfaces such as louvered fins. Although acceptable continuous surface geometries such as bumped fin geometries are in use, the impacts of changing the parameters of this geometry are unknown. This study investigates the transport characteristics of bumped fins in the transitional flow regime using unsteady multi-dimensional …

Modeling And Simulations Of Diphasic Composites For Development Of High Energy Density Dielectrics, Sandeep K. Patil

Doctoral Dissertations

"This research is focused on diphasic dielectric composites for high energy density storage applications in pulsed power and power distribution systems. Composite materials are particularly attractive because they can synergistically combine high permittivity with high breakdown strength of the individual phases. Energy density, which captures permittivity and dielectric breakdown strength as vital material parameters, dominates this research challenge. Avenues for increasing the effective permittivity and breakdown strength may be found by gaining fundamental understanding of the response of diphasic dielectrics to an applied electric field. Improved understanding of these characteristics will ultimately lead to dielectrics with increased energy storage densities. …

Multiple-Input Multiple-Output Wireless Communications With Imperfect Channel Knowledge, Christopher Potter

Doctoral Dissertations

"In the first work a recurrent neural network (RNN) is employed for MIMO channel prediction. A novel PSO-EA-DEPSO off-line training algorithm is presented and is shown to outperform PSO, PSO-EA, and DEPSO. This predictor is shown to be robust to varying channel scenarios. New expressions for the received SNR, array gain, average probability of error, and diversity gain are derived. Next, a new expression for the outage capacity of a MIMO system with no CSI at the transmitter and an estimate at the receiver is presented. Since the outage capacity is a function of the first and second moments of …

Modeling, Analysis And Experimentation For Building Ice Parts With Supports Using Rapid Freeze Prototyping, Frances D. Bryant

Doctoral Dissertations

"Rapid Freeze Prototyping (RFP) is a freeform fabrication method that freezes water droplets into ice in a layer-by-layer manner to additively create a 3-dimensional part. Each layer of a geometry is deposited and allowed to freeze before the next layer is added. Ice parts produced by RFP can be used in investment casting to replace wax patterns and in other applications which may benefit from the unconventional method of using ice as a pattern or mold. More recently, a sacrificial support material has been incorporated into RFP so that over-hung areas and complex geometries can be fabricated. The research presented …

Quantifying The Desired Degree Of Supply Chain Flexibility, Poorna Marappa

Masters Theses

"The dynamic nature of today's market drives the need for flexibility in supply chains. The ever-growing need for and importance of flexibility in supply chains has motivated researchers to develop frameworks to achieve supply chain flexibility. Much of the research on supply chain flexibility focuses on drivers of the need for flexibility and classification of supply chain flexibility. Existing frameworks for determining the desired degree of flexibility in supply chains give an overview methodology; however, a comprehensive framework is absent. This research proposes a comprehensive framework to quantify the desired degree of flexibility in supply chains and accordingly determine its …

Removal Of Heavy Metals From Electroplating Wastewater Using Rice Husk And Coconut Coir, Frency Mathew

Masters Theses

"Heavy metal toxicity due to industrial wastewater has been a threat to the environment for the past many decades, especially in the developing countries such as India, China and Thailand where cost effectiveness of the removal process is a major factor. In this research, the effectiveness of two natural adsorbents, rice husk (RH) and coconut coir (CC), which are cheaply available in these countries for the removal of heavy metals from electroplating wastewaters were studied"--Abstract, page iii.

Methodology And Process To Accompany A Virtual Geotechnical Database For The St. Louis Metropolitan Area, Katherine Leigh Onstad

Masters Theses

"The St. Louis metropolitan (STL) area, which spans Missouri and Illinois, currently has no overarching organization of geospatial data (geodata). The two states have their own geodata, using their own individual standards. The development of a virtual geotechnical database (VGDB) encompassing the entire STL area on both sides of the Mississippi River is a solution to the data sharing and standardization problem of this area. The VGDB integrates geodata from disparate sources into a geographic information systems (GIS) database accessible via the internet. The creation of the STL area VGDB consisted of three parts: 1) compiling the geodata; 2) formatting …

Formation And Removal Of Pesticides And Pesticide Transformation Products During Water Treatment, Evelyn F. Chamberlain

Doctoral Dissertations

"A comprehensive suite of over 60 pesticides (herbicides, insecticides, and fungicides) representing a variety of classes at environmentally relevant concentrations (low µg/L) were screened for reactivity under typical drinking water conditions and dosages. The most common oxidants/transformation agents in water treatment systems were examined for reactivity including free and combined chlorine, chlorine dioxide, permanganate, ozone, hydrogen peroxide, ultraviolet radiation, and high pH (alkaline hydrolysis). Due to the broad nature of the study, pesticide compounds were analyzed as multiple mixes broken into two groups based on analytical methods, those analyzed by GC/ECD and those by LC/MS. Combinations of reactive disinfectant/oxidant and …

Universal Electric And Magnetic Fields Analyzer System, Yong Cheh Ho

Masters Theses

"Near-field probing is often used to measure the electric and magnetic fields above a printed circuit board (PCB) or integrated circuits (IC) chip in order to identify the sources and coupling paths of an electromagnetic interference (EMI) problem.

A wideband universal field analyzer was designed, built and tested in this thesis. The system is able to provide fast field scanning over a wide frequency range in lieu of its capabilities to measure multiple field components using a single probe design. Central to the system operation is the phase-shifting concept that provides wideband and wide- range phase-shifting.

The complete universal field …

Manufacturing Of Transparent Composites Using Vacuum Infusion Process, Jason Niles Gallagher

Masters Theses

"Glass is the most commonly used transparent material. However, glass is not suitable where low weight and high strength are required. For many applications there exists a need for mechanically strong composite materials of high optical quality and transparency equivalent to window glass. Glass fiber reinforced transparent composite is a viable solution. Transparency is maintained by precisely matching the refractive index of the matrix with that of the glass fiber. Aircraft canopies and transparent armor can be potential applications for this new class of materials.

In the present work, transparent composites are manufactured using vacuum infusion process. Both rectangular glass …

Block Level Link Path Design And Multilayer Via Transition Model Assembly Using S-Parameters, Francesco De Paulis

Masters Theses

"In high-speed data communication systems the complexity of link path between transmitters and receivers present a challenge for designers to maintain an acceptable bit error rate. An approach is presented in this thesis to design the link path on a block-by-block basis. The unique advantage of this approach lies on the physics-based model of each block, which then relates performance to geometry and makes design improvement and optimization possible. A tool based on the manipulation of frequency domain data has been designed to help in the design and analysis process of fast communication systems. It accepts as inputs the frequency …

Design For Manufacturing For Friction Stir Welding, Harish Bagaitkar

Masters Theses

"This thesis is divided in two parts. In the first part, technical feasibility of implementing Friction Stir Welding (FSW) for automobile chassis fabrication is discussed using a case study. In the case study, Design for Manufacturing (DFM) principles are applied to manufacture an aluminum automobile chassis. Various DFM issues such as Tool Accessibility Issue, Joint Configuration Issue, and Fixture Support Issue along with relevant guidelines such as component geometry change and component elimination are discussed in the first section. Results show that more than 50% of the chassis joints can be welded using FSW technique. The second part of the …

Application Of Product Family Design For Engineered Systems In Changing Market Space, Mohit Goswami

Masters Theses

"The focus of this paper is on the design of an engineered system for a changing market space. Due to the dynamic nature of the customer requirements, the specification of product offerings in a particular market may change. Manufacturers need to strategically design their product portfolio in such a way that their profitability is maximized, while deploying the right number of platforms necessary for deriving product variants. Depending on the system architecture, subsystems can be classified into one of the two types: scalar subsystems and modular subsystems. Each subsystem is defined by various parameters, performance criteria, and physical compatibility constraints. …

Derivation Of New Double-Input Dc-Dc Converters Using The Building Block Methodology, Karteek Gummi

Masters Theses

"In most power electronic systems, the instantaneous input and output power vary by time and are not exactly identical with each other. Hence, providing a good match between them is a complicated task to deal with if not impossible. Furthermore, due to the wide variation range of the processed power, the overall efficiency of the system is not high. The solution is to hybridize the system using an energy storage unit like in hybrid electric vehicles, power factor correction systems, and photovoltaic systems. Multi-input converters play a key role in such hybridized systems, where it is required to have more …

Defect-Tolerance And Testing For Configurable Nano-Crossbars, Mandar V. Joshi

Masters Theses

"Moore's Law speculated a trend in computation technology in terms of number of transistors per unit area that would double roughly every two years. Even after 40 years of this prediction, current technologies have been following it successfully. There are however, certain physical limitations of current CMOS that would result in fundamental obstructions to continuation of Moore's Law. Although there is a debate amongst experts on how much time it would take for this to happen, it is certain that some entirely new paradigms for semiconductor electronics would be needed to replace CMOS and to delay the end of Moore's …

Fabrication Of Soy Oil Epoxy Resin Based Composites, Vinay Prabhakar Pai

Masters Theses

"A renewable resource derived epoxidized ester - Epoxidized Allyl Soyate (EAS) yields a versatile epoxy resin system that can be used in pure form combination with bis-phenol epoxy systems to obtain high strength composite materials. EAS containing composites materials exhibit higher toughness and impact resistance than the traditional bis-phenol epoxy composites. These resin systems were found to be compatible with different fibers and screens such as glass fibers, glass mats, carbon fibers and metallic wire screens including those obtained from an automobile tire recycling process. The materials were tested for mechanical properties including tensile and flexure strengths. The highest tensile …

Performance Of Fire-Damaged Prestressed Concrete Bridges, Wendy Leann Moore

Masters Theses

"The purpose of this experimental program was to develop and analyze the effects of fire damage on prestressed concrete bridges. Flexural strength and serviceability of the bridge were measured by inputting fire damaged data into a parametric study spreadsheet consisting of a typical 3-span continuous prestressed concrete bridge. Data was obtained by exposing two types of specimens to different levels of elevated temperatures and then cooling them at room temperature to simulate fire damage. The two specimen types were prestressing strands which were tested in tension and concrete blocks with a single prestressing strand embedded in the center, which were …

Hazards Assessment Of St. Charles County - Earthquakes And Floods, Amy Lynn Krauch

Masters Theses

"Located on the northernmost limits of the St. Louis metropolitan area, St. Charles County has been, and continues to be, one of the fastest-growing counties in the country. The county consists of several major cities featuring extensive industry, retail, and agriculture. Bounded by the Missouri River on the south and the Mississippi River on the north and east, St. Charles County is predominantly flat, low-lying terrain at great risk to periodic flooding. The county is also well within the area of influence for several local seismic zones, increasing the susceptibility to earthquake damage. Given the apparent risk to both flood …

Effect Of Sparger Design On Hydrodynamics Of A Gas Recirculation Anaerobic Bioreactor, Rajneesh Varma, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Effects of Sparger Design and Gas Flow Rate On, Gas Holdup Distribution and Liquid (Slurry) Recirculation Velocity Have Been Studied in a Surrogate Anaerobic Bioreactor Used for Treating Bovine Waste with a Conical Bottom Mixed by Gas Recirculation. a Single Orifice Sparger (SOS) and a Multi-Orifice Ring Sparger (MORS) with the Same Orifice Open Area and Gas Flow Rates (Hence the Same Process Power Input) Are Compared in This Study. the Advanced Non-Invasive Techniques of Computer Automated Tomography (CT) and Computer Automated Radioactive Particle Tracking (CARPT) Were Employed to Determine Gas Holdup, Liquid Recirculation Velocity, and the Poorly Mixed …

Numerical Simulation Of Gas-Solid Dynamics In A Circulating Fluidized-Bed Riser With Geldart Group B Particles, S. Vaishali, Shantanu Roy, Satish Bhusarapu, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Circulating Fluidized-Bed (CFB) Risers with Geldart Group B Particles Have Found Significant Application in Combustion Reactions. the Present Work Attempts to Study the Solids Flow Dynamics in a CFB Riser that is Operated with Group B Particles, using Computational Fluid Dynamics (CFD) Techniques. the Key Feature in the Present Study is that the Various Closure Schemes in the CFD Model Have Been Evaluated Against Data from Non-Invasive Experimental Techniques: Computer Automated Radioactive Particle Tracking (CARPT) for Solids Velocity Field and Computed Tomography (CT) for Solids Holdup. Since Solids Flow in a Riser is Multiscale in Character, in Addition to the …

Collaborative Routing Algorithm For Wireless Sensor Network Longevity, Shishir Bashyal, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This study proposes a new parameter for evaluating longevity of wireless sensor networks after showing that the existing parameters do not properly evaluate the performance of algorithms in increasing longevity. This study also proposes an ant inspired Collaborative Routing Algorithm for Wireless Sensor Network Longevity (CRAWL) that has scalability and adaptability features required in most wireless sensor networks. Using the proposed longevity metrics and implementing the algorithm in simulations, it is shown that CRAWL is much more adaptive to non-uniform distribution of available energy in sensor networks. The performance of CRAWL is compared to that of a non-collaborative algorithm. Both …

Variable Scaling For Time Series Prediction: Application To The Estsp'07 And The Nn3 Forecasting Competitions, Amaury Lendasse, Elia Liitiainen

Engineering Management and Systems Engineering Faculty Research & Creative Works

In This Paper, Variable Selection and Variable Scaling Are Used in Order to Select the Best Regressor for the Problem of Time Series Prediction. Direct Prediction Methodology is Used Instead of the Classic Recursive Methodology. Least Squares Support Vector Machines (LS-SVM) and K-NN Approximator Are Used in Order to Avoid Local Minimal in the Training Phase of the Model. the Global Methodology is Applied to the Estsp'07 Competition Dataset [1] and the Dataset B of the Nn3 Forecasting Competition [2]. ©2007 IEEE.

An Empirical Dependence Mesaures Based On Residual Variance Estimation, Nima Reyhani, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

In This Paper, a Solution to Empirical Dependency Measure is Proposed. the Main Idea is to Use the Notion of Predictability as a Basis for Dependency Definition. Considering Any Nonlinear Regression Function between Two Random Variables, the Power of Regression Residuals or Noise Variance Defines the Desired Dependency Measure. the Residuals Variance Can Be Directly Computed by Estimators Without Finding the Best Fit Curve. the Paper Shows the Conditions on Which Two Random Variables Are Independent According to the Estimated Residuals Variance. the Existence of Residual Variance, or Noise Variance Estimators Make It Possible to Define Such Practical Measure for …

Time Series Prediction As A Problem Of Missing Values: Application To Estsp2007 And Nn3 Competition Benchmarks, Antti Sorjamaa, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

In This Paper, Time Series Prediction is Considered as a Problem of Missing Values. a Method for the Determination of the Missing Time Series Values is Presented. the Method is based on Two Projection Methods: A Nonlinear One (Self-Organized Maps) and a Linear One (Empirical Orthogonal Functions). the Presented Global Methodology Combines the Advantages of Both Methods to Get Accurate Candidates for the Prediction Values. the Methods Are Applied to Two Time Series Competition Datasets. ©2007 IEEE.

Using Science, Engineering, And Education To Address Water Supply Challenges In The Highlands Of Guatemala, Andrew Curtis Elmore, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

The Guatemalan Highlands is a Popular Destination for Non-Government Organizations Interested in Performing Relief Projects. U.S.-Based Organizations Such as Rotary International, Engineers Without Borders, and Various Religious Organizations Travel to Guatemala to Conduct Humanitarian Activities Which May Be Effective for the Short Term, But It is Not Clear that the Efforts Have a Systematic Impact. Students and Faculty at the University of Missouri-Rolla Have Systematically Studied Water Supply Issues Including Undergraduate and Graduate Research Projects and Undergraduate Engineering Courses Such as International Capstone Design. Materials Engineers Have Been Involved in the Study of Ceramic-Based Water Treatment Devices. These Microfilters Have …

Function-Technology-Based Product Platform Formation, Rupesh Kumar, Venkat Allada

Engineering Management and Systems Engineering Faculty Research & Creative Works

Product platforms have been effectively used by many successful companies for product family design. Technological advancements and changes in customer needs pose problems for robustly designing product platforms over a given planning horizon. to date, most product platform formation approaches are directed by structural (subassemblies and components) considerations and are seldom undertaken at the conceptual design stage. We argue that product platform design should commence at the conceptual design stage rather than the detailed design stage. It is noteworthy that physical structures are the end results of designs already frozen at higher level of functional abstraction. Hence, tackling the platform …

A Hardware Threat Modeling Concept For Trustable Integrated Circuits, Jia Di, Scott C. Smith

Electrical and Computer Engineering Faculty Research & Creative Works

Similar to the effects of software viruses, hardware can also be compromised by introduction of malicious logic into circuits to cause unwanted system behaviors. This can be done by changing or adding internal logic, in such a way that it is undetectable using traditional testing and verification tools and techniques. Therefore, the user of the circuit needs to decide whether it can be trusted, i.e., it only performs functions defined in the original circuit specification (no more and no less), before employing it in the system. in this paper, a preliminary methodology is proposed to model potential hardware threats in …

A Systematic Semi-Numerical Approach For Modeling Of Signal And Power Integrity Of Electronic Packages, Er Ping Li, En Xiao Liu, Zaw Zaw Oo, Xingchang Wei, Yaojiang Zhang, R. Vahldieck

Electrical and Computer Engineering Faculty Research & Creative Works

A novel method for system-level modeling of advanced electronic packages is presented which is able to provide fast yet accurate simulation for signal and power integrity analysis of the multilayered electronic packages. the method is a semi-numerical approach based on the combination of the moment method and the scattering matrix method. © 2007 IEEE.

A Closed Form Solution For Multiple-Input Spike Based Adaptive Filters, Il Park, António R.C. Paiva, José C. Príncipe, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Neurons are point process systems, in the sense that the inputs and output which are spike trains can be treated as point processes. System identification of a point process system has been studied mostly with single input. However, multiple input is required in many applications such as liquid state machines or neural prosthetics. We propose a simple multiple-input spike based adaptive filter which is based on an integrate-and-fire neuron model. The optimal closed solution is derived, and the performance is analyzed with respect to noise in various parameters and measurement. ©2007 IEEE.