Engineering Commons^™

Laser Deposition Cladding On-Line Inspection Using 3-D Scanner, Yu Yang, Todd E. Sparks, Jianzhong Ruan, Lan Ren, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser deposition directly deposits metal cladding to fabricate and repair components. In order to finish the fabrication or repair, 3-D shape of the deposition needs to be inspected, and thus it can be determined if it has sufficient cladding to fabricate a part after deposition process. In the present hybrid system in the Laser Aided Manufacturing Lab (LAMP) at the University of Missouri - Rolla, a CMM system is used to do the inspection. A CMM requires point-by-point contact, which is time consuming and difficult to plan for an irregular deposition geometry. Also, the CMM is a separate device, which …

Wireless Multiple Access Communication Over Collision Frequency Shift Channels, Chen Xia

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

A collision frequency shift keyed system (CFSK) using M-ary FSK signaling is investigated. CFSK is a wireless multiple access system in which users access a channel without cooperation. This results in collisions when users simultaneously transmit signals in the same frequency band. However, analysis has shown that the CFSK system has the potential to achieve greater capacities than binary multiple access systems.

In this dissertation, bounds on the multiuser capacity of the noisy synchronous and asynchronous CFSK channel are derived. Analytical models are designed for investigating these capacity results. It is shown that the capacity of the noisy synchronous CFSK …

Ceas E-News 08.07.2007, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Eight students from India's IIT assist in CEAS research projects

Ellipsometer Or Polarimeter And The Like System With Multiple Detector Element Detector In Environmental Control Chamber Including Secure Sample Access, John A. Woollam, Gregory K. Pribil, Martin M. Liphardt, James Welch

Department of Electrical and Computer Engineering: Faculty Publications

A spectrophotometer, ellipsometer or polarimeter or the like system with a spectroscopic source of wavelengths and a detector with multiple detector elements for simultaneous monitoring of a number of wavelengths in an environmental control chamber which optionally provides for secured sample entry, and methodology of use.

A Duplex Theory Of Spike Coding In The Early Stages Of The Auditory System, Ismail Uysal, Harsha Sathyendra, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

We propose a duplex theory of spike coding in the early stages of the auditory system based on the intensity and noise levels of the acoustic stimuli. According to this concept, at low intensity levels, where auditory nerve firings cannot generate a high enough synchrony among neuron ensembles, rate coding is more likely favored against phase-locking via synchrony coding. To the contrary, at conversational intensity levels, phase synchrony coding is preferred due to its superior and highly noise robust performance. The theory is supported by both evidence from biology, as well as from experimental simulations using biologically plausible models of …

State-Of-The-Art And Evolution In Public Data Sets And Competitions For System Identification, Time Series Prediction And Pattern Recognition, Joos Vandewalle, Johan Suykens, Bart De Moor, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

It is the Aim of Reproducible Research to Provide Mechanisms for Objective Comparison of Methods, Algorithms, Software and Procedures in Various Research Topics. in This Paper, We Discuss the Role of Data Sets, Benchmarks and Competitions in the Fields of System Identification, Time Series Prediction, Classification, and Pattern Recognition in View of Creating an Environment of Reproducible Research. Important Elements Are the Data Sets, their Origin, and the Comparison Measures that Will Be Used to Rank the Performance of the Methods. the Issues Are Discussed, a Comparison is Made and Recommendations Are Given. © 2007 IEEE.

Effects Of Surface-Deposited Nanocrystalline Chromite Thin Films On The Performance Of A Ferritic Interconnect Alloy, I. Belogolovsky, X. D. Zhou, H. Kurokawa, P. Y. Hou, S. Visco, H. U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

LaCrO₃ -Based nanocrystalline thin films, substituted with Sr and Zn and coated onto a Fe-26 atom % Cr Ebrite alloy were evaluated at 750-900°C as potential enhancers of oxide properties in ferritic alloy interconnects of a solid oxide fuel cell. It was found that at 750°C the coatings provided (i) lower oxidation rates, (ii) increased electrical conductivity, (iii) protection during 24 h cycling and at least 2375 h of isothermal oxidation, and (iv) a fine-grained and uniform oxide microstructure. Although after oxidation at 850°C the grains grew substantially and the scale seemed to be overgrowing the film, conductivity and …

Control Of Nonlinear Mechatronic Systems, Enver Tatlicioglu

All Dissertations

This dissertation is divided into four self-contained chapters. In Chapter 1, an adaptive nonlinear tracking controller for kinematically redundant robot manipulators is presented. Past research efforts have focused on the end-effector tracking control of redundant robots because of their increased dexterity over their non-redundant counterparts. This work utilizes an adaptive full-state feedback quaternion based controller developed in [1] and focuses on the design of a general sub-task controller. This sub-task controller does not affect the position and orientation tracking control objectives, but instead projects a preference on the configuration of the manipulator based on sub-task objectives such as the following: …

Manufacturable Process And Tool For High Performance Metal/High-K Gate Dielectric Stacks For Sub-45 Nm Cmos & Related Devices, Aarthi Venkateshan

All Dissertations

Off state leakage current related power dominates the CMOS heat dissipation problem of state of the art silicon integrated circuits. In this study, this issue has been addressed in terms of a low-cost single wafer processing (SWP) technique using a single tool for the fabrication of high-κ dielectric gate stacks for sub-45 nm CMOS. A system for monolayer photoassisted deposition was modified to deposit high-quality HfO2 films with in-situ clean, in-situ oxide film deposition, and in-situ anneal capability. The system was automated with Labview 8.2 for gas/precursor delivery, substrate temperature and UV lamp. The gold-hafnium oxide-aluminum (Au-HfO2-Al) stacks processed in …

In Situ Photopolymerized Hydrogels For Enhancing Protein Delivery, Chien-Chi Lin

All Dissertations

In recent years, there has been immense interest in the utilization of photopolymerized hydrogels as carriers for controlled protein delivery and cell scaffolds for tissue engineering applications. Although poly(ethylene glycol) (PEG)-based hydrogels formed from mild photopolymerization methods have been suggested as biocompatible matrices that allow for safely encapsulating biomolecules including proteins, peptides, DNA, and cells, the adverse effects of photopolymerization reactions on the encapsulated proteins have largely been overlooked. In addition, conventional hydrophilic hydrogels fail to effectively control protein delivery rates due to their high permeability. These two problems are critical since the delivery of protein therapeutics from hydrogel matrices …

Nonlinear Control Strategies For Advanced Vehicle Thermal Management Systems, Mohammad Salah

All Dissertations

Advanced thermal management systems for internal combustion engines can improve coolant temperature regulation and servo-motor power consumption to positively impact the tailpipe emissions, fuel economy, and parasitic losses by better regulating the combustion process with multiple computer controlled components. The traditional thermostat valve, coolant pump, and clutch-driven radiator fan are upgraded with servo-motor actuators. When the system components function harmoniously, desired thermal conditions can be accomplished in a power efficient manner. Although the vehicle's mechanical loads can be driven by electric servo-motors, the power demands often require large actuator sizes and electrical currents. Integrating hydraulically-driven actuators in the cooling circuit …

Nonlinear Vibration And Frequency Response Analysis Of Nanomechanical Cantilever Beams, Seyed Nima Mahmoodi

All Dissertations

Microcantilevers are one the most commonly utilized microelectromechanical systems in a variant of the ultra-precise scanning and characterization application. Of particular interest, the problem of vibrations of microcantilevers has recently received considerable attention due to its application in several nanotechnological instruments such as atomic force microscopy, nanomechanical cantilever sensors and friction force microscopy. For applications such as these, the problem of coupled flexural-torsional nonlinear vibrations of a piezoelectrically-actuated microcantilever beam is considered in this dissertation. The actuation and sensing are both facilitated through bonding a piezoelectric layer (here, ZnO) on the microcantilever surface. The beam is considered to have simultaneous …

Differentiation Modulation Of Adult Stem Cells In An Adipose System, Aditya Chaubey

All Dissertations

The need for soft tissue reconstruction or augmentation has increased continuously over the years. This need is compounded by patients suffering from post-traumatic repair and congenital soft-tissue deformities. All the current options available to treat the soft tissue deformities have inherent difficulties associated with them. Hence, more research is needed to come up with a better solution to this problem which is only going to increase in magnitude. Tissue engineering is a relatively new technique which has the potential to deliver a cell-based device which can overcome the problems associated with traditional therapies. However, before it becomes clinically viable we …

Thermodynamic Adsorption Studies Of Peptides On Well-Defined, Surface-Confined Polymers With Applications In Membrane Bioseparations, Nripen Singh

All Dissertations

This dissertation deals with the fundamental studies of peptide adsorption on surfaces modified by surface-confined polymer films, with an application emphasis on membrane bioseparations. In order to understand protein adsorption at a fundamental level, it is important to study the specific residue-level interactions with surfaces. Keeping this idea in view, the present work describes experimental measurements of submolecular-level interaction energies involved in the process of peptide adsorption on polymer films using surface plasmon resonance spectroscopy. Gibbs energy change on adsorption (ΔGad) for tyrosine, phenylalanine, and glycine homopeptides were measured at 25 °C and pH 7 on highly uniform, nanothin polymer …

Heuristics For Scheduling Reentrant Flexible Job Shops With Sequence-Dependent Setup Times And Limited Buffer Capacities, Jakrawarn Kunadilok

All Dissertations

This research addresses the problem of scheduling complex job shops with minimizing total weighted tardiness as the objective. The complex job shop is characterized by reentrant job flow through a number of different work centers that contain one or more identical parallel machines. The processing restrictions for the complex job shop include possible non-zero ready times and sequence-dependent setup times. We categorize the complex job shop into two classes: the complex job shop with infinite or finite buffer capacities. We propose three solution methodologies for scheduling the problem with infinite buffer capacities. The first method is the use of mixed …

Non-Boltzamann Sampling For The Accurate Calculation Of Peptide-Surface Adsorption Free Energy, Feng Wang

All Dissertations

%Abstract
The objectives of this project are 1) the setup and refinement of peptide-SAM surface model systems with explicit water using CHARMM and 2) the development of up-to-date simulation protocols for the accurate calculation of adsorption free energy by incorporating the recent development of non-Boltzmann sampling methods in molecular dynamics and applying it for the calculation of adsorption free energy of short peptides onto well-characterized self-assembled monolayers, which is important for understanding protein/surface interactions.
A software package called the Simulation Template Engine for Peptides at Surfaces (STEPS) was developed for the fulfillment of the first objective. It facilitates the automatic …

Control Techniques For Robot Manipulator Systems With Modeling Uncertainties, David Braganza

All Dissertations

This dissertation describes the design and implementation of various nonlinear control strategies for robot manipulators whose dynamic or kinematic models are uncertain. Chapter 2 describes the development of an adaptive task-space tracking controller for robot manipulators with uncertainty in the kinematic and dynamic models. The controller is developed based on the unit quaternion representation so that singularities associated with the otherwise commonly used three parameter representations are avoided. Experimental results for a planar application of the Barrett whole arm manipulator (WAM) are provided to illustrate the performance of the developed adaptive controller.
The controller developed in Chapter 2 requires the …

Biodiesel Forming Reactions Using Heterogneous Catalysis, Yijun Liu

All Dissertations

Biodiesel synthesis from biomass provides a means for utilizing effectively renewable resources, a way to convert waste vegetable oils and animal fats to a useful product, a way to recycle carbon dioxide for a combustion fuel, and production of a fuel that is biodegradable, non-toxic, and has a lower emission profile than petroleum-diesel. Free fatty acid (FFA) esterification and triglyceride (TG) transesterification with low molecular weight alcohols constitute the synthetic routes to prepare biodiesel from lipid feedstocks. This project was aimed at developing a better understanding of important fundamental issues involved in heterogeneous catalyzed biodiesel forming reactions using mainly model …

Activation Of Systemic Adhesion Molecules And C Reactive Protein In Response To Biomaterial Particle Induced Cytokine Production, Robin Graham

All Dissertations

Chronic inflammation has been identified as a major contributor to many diseases including, atherosclerosis, osteoporosis, dementia, Alzheimer's disease and type 2 diabetes, to name a few. Many of the same markers of inflammation found in the diseases listed above, including IL-1, IL-6, TNF-α, NF-B and adhesion molecules, have also been found in wear debris induced osteolysis. While the local response to biomaterial wear debris has been characterized quite extensively, very little is known about the systemic effect of biomaterial wear debris on the inflammatory system. The objectives of this study were to evaluate the in vitro and in vivo inflammatory …

Heterogeneous Catalysis And Biodiesel Forming Reactions, Dora Lopez

All Dissertations

Biodiesel, defined as 'a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats', is finding favor commercially worldwide. The objective of this study is to evaluate the use of solid catalysts for triglyceride transesterification and carboxylic acid esterification to produce biodiesel fuel.
Processes using mainly homogeneous alkali catalysts (such as NaOH, KOH, and methoxides) have been shown to be effective for biodiesel synthesis when dealing with virgin oil feedstocks. Use of acid catalysts (e.g., H2SO4) becomes important when processing low quality feedstocks that contain appreciable amounts of free fatty acids, such as …

Characterization Of Recycled Aged Crm Binders, Soon-Jae Lee

All Dissertations

The incorporation of conventional reclaimed asphalt pavement (RAP) in hot-mix asphalt (HMA) pavements has become routine in many states around the United States and many other countries all over the world. In addition, the recycling of crumb rubber modified (CRM) materials has been an area of interest since CRM was first used in asphalt paving materials over 40 years ago. Previous research on the recycling of rubberized asphalt concrete (RAC) materials have been limited and focused mainly on the mixture properties at the location of in-field paving. However, for the long-term performance characterizations, it is needed to investigate the aging …

Measurement And Analysis Of Hydromechanical Effects In Fractured Rock, Todd Schweisinger

All Dissertations

Fractures in rock hold important stores of water and petroleum, and slight changes in fracture aperture accompanying drawdown from pumping wells play a key role in recovering these resources. Four accomplishments are described that advance insight into the behavior and characterization of fractured crystalline rock.
First was the development of two removable borehole extensometers that enable small axial displacements to be measured during hydraulic well tests. The extensometers consist of four major components: 1.) a pair of anchors; 2.) a displacement transducer 3.) a registration system, and; 4.) a temperature-compensated reference rod. One extensometer uses an axial reference rod with …

Evaluation Of Lithium Based Deicing Chemicals For Mitigating Asr In Concrete Pavement, Senthil Soundarapandian

All Dissertations

Deicing and anti-icing chemicals such as alkali-acetate and alkali-formate based formulations are increasingly being used on airfield pavements. Among these new deicers, potassium acetate-based formulations are widely used due to their environmentally friendly nature and effectiveness in melting and undercutting ice at low temperatures. Recent research on premature deterioration of airfield pavements due to alkali-silica reaction (ASR) has indicated that alkali-acetate and alkali-formate deicers such as potassium acetate and sodium formate may have been responsible for the observed distress. In an effort to develop a deicing chemical that is benign to concrete from an ASR standpoint, a new deicing formulation …

The Study On Inland Container Terminal Logistics System Simulation, Jun Wu

World Maritime University Dissertations

No abstract provided.

Research On Logistics Operation Mode Of Shanghai 2010 Expo, Jiaying Chen

World Maritime University Dissertations

No abstract provided.

Shipping Economic Analysis Of Enlargement For Containership To Maersk Ae10, Xiaodi Chen

World Maritime University Dissertations

No abstract provided.

The Study On Function And Application Of Financial Leasing For The Development Of Small-Medium Shipping Enterprises In China, Tian Wen

World Maritime University Dissertations

No abstract provided.

Choice And Optimization Of Forecasting Models For Container Port Throughput, Qingcheng Xue

World Maritime University Dissertations

No abstract provided.

Application Of Iso Tank In Chemimcal Logisitcs In China And Relative Issues, Hao Zhang

World Maritime University Dissertations

No abstract provided.

Research On Establishment Of Oil Spill Emergency Response System In China Qingdao Port Based On Ann, Ge Zhang

World Maritime University Dissertations

No abstract provided.