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Articles 2071 - 2100 of 3180

Full-Text Articles in Engineering

Parametric Cost Estimation Model For Microchannel Bonding Process Based On Activity Based Costing, Panita Suebvisai Jan 2013

Parametric Cost Estimation Model For Microchannel Bonding Process Based On Activity Based Costing, Panita Suebvisai

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The microchannel bonding process was developed to decrease product size and improve product performance. As the microchannel bonding process has moved from research to industrial manufacturing, it has become increasingly important to create a model to more accurately estimate the costs associated with this process. However, due to problems in project planning and limitations in funding, most microchannel bonding projects appear to have schedule slips and cost overruns. This dissertation presents a cost estimation model that links activity-based costing with parametric cost estimation. A parametric cost model has been designed to improve decision making in the microchannel bonding process, specifically …

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Nano-Morphology Of Polymer Bulk Herojunctions Studied By Time-Resolved Synchrotron X-Ray Scattering, Soo Kim Jan 2013

Nano-Morphology Of Polymer Bulk Herojunctions Studied By Time-Resolved Synchrotron X-Ray Scattering, Soo Kim

Material Science and Engineering Dissertations - Archive

This study investigates the phase transformation of an active layer in organic photovoltaics (OPV) during film deposition and post thermal treatment as well as effects of phase transformation on OPV performance. For this purpose, small - and wide angle X-ray scattering technique (SAXS and WAXS) was applied to examine the phase separation mechanism at relevant fabrication condition of the highest OPV device performance. The poly(3-alkylthiophene)/[6,6]-phenyl-C61 butyric acid methylester (P3AT/PCBM) blend sample was employed in order to study phase transformation of the active layer systemically.Our exploration with SAXS and WAXS technique found that the polarity of the substrate, a solubility, and …

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Fabrication And Characterization Of Barium Titanate Thin Film On Polycrystalline Nickel Substrate, Parisa Sahebi Jan 2013

Fabrication And Characterization Of Barium Titanate Thin Film On Polycrystalline Nickel Substrate, Parisa Sahebi

Material Science and Engineering Theses - Archive

Ferroelectric BaTiO₃(BTO) thin films were deposited on polycrystalline nickel disks and silicon wafer substrates by rf magnetron sputtering. Nickel oxide (NiO) and nanocrystalline nickel (nc-Ni) layers were used as interfacial buffer layers. Microstructural studies with X-ray diffraction and transmission electron microscopy reveal that the BTO films deposited at temperatures lower than 700℃ have an amorphous structure. However, the BTO films sputtered at temperatures higher than 700℃ are partially crystalline. BTO films have a good and continuous interface with both interfacial layers with no interdiffusion or reaction with the substrates. In the case of BTO deposition with nc-Ni interlayer at higher …

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Investigation Of Nanoparticle Delivery To Cancer Cells By Conjugation With Various Targeting Moieties, Leila Hossein Rashidi Jan 2013

Investigation Of Nanoparticle Delivery To Cancer Cells By Conjugation With Various Targeting Moieties, Leila Hossein Rashidi

Bioengineering Theses - Archive

Recently, mapping and profiling of specific tumor biomarkers characterizing cancer cells, followed by understanding of signal cascades involved in the pathogenesis of tumors (targeted therapy), as well as diagnosis in early stages, have become promising topics in cancer research. Since, the most considerable limitations of conventional therapies and diagnostic modalities are associated with nonspecific targeting; designing intelligent new anti-cancer nanocarries improved by targeting biomolecules could enhance therapeutic efficiencies as well as diagnosis in early stage of cancer. Active targeting which is based on the surface accessibility and the high level of expression of specific cancer antigens has attracted much attention …

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Effect Of Body Mass Index On The Biomechanical Properties Of Anterior Vaginal Wall Tissue Of Prolapsed Patients, Sandra Gabriela Ochoa Lopez Jan 2013

Effect Of Body Mass Index On The Biomechanical Properties Of Anterior Vaginal Wall Tissue Of Prolapsed Patients, Sandra Gabriela Ochoa Lopez

Bioengineering Theses - Archive

Anterior Vaginal Wall (AVW) prolapse is a bothersome condition that affects thousands of women. Its onset and progression is not well understood but is thought to be multifactorial. Biomechanical properties of AVW tissue from prolapsed patients have been measured in-vitro using excised tissue specimens with great variability found in results, possibly from differences in tissue preparation, setting, preservation time, temperature, hydration, etc. In-vivo test using a BTC-2000TM cutometer-like device has recently been developed that measures the tissue uplift under suction pressure load. In this study, a systematical analysis of biomechanical property measurements from AVW tissues was done, including both in-vitro …

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Measurement Of Transverse Relaxation Times Of Cerebral Metabolites In Brain Tumors, Akshay Madan Jan 2013

Measurement Of Transverse Relaxation Times Of Cerebral Metabolites In Brain Tumors, Akshay Madan

Bioengineering Theses - Archive

Proton (¹H) magnetic resonance spectroscopy (MRS) provides a non-invasive means of assessing metabolite concentration for a range of biologically important cerebral compounds in vivo. To extract quantitative information, additional data regarding proton spin relaxation phenomena is critical. Transverse relaxation times (T₂) of cellular metabolites depend on the local molecular environment in which they reside. Several neurological diseases alter the molecular environment, which may be reflected in the changes of the T₂ relaxation times. Therefore alterations in T₂ in tumors may provide important information about the local environment and a potential non-invasive diagnostic tool. Thirty-seven adult patients with gliomas and 11 …

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Microfluidic Chip-Based Fabrication Of Hollow Alginate Microfiber For Enzyme Entrapment And Reaction, Uyen Hoang Thao Pham Jan 2013

Microfluidic Chip-Based Fabrication Of Hollow Alginate Microfiber For Enzyme Entrapment And Reaction, Uyen Hoang Thao Pham

Bioengineering Theses - Archive

This thesis demonstrates a simple process to generate alginate hollow microfibers by using a non-lithographic PDMS microfluidic device. The microfluidic device was fabricated by a novel template method in a wet lab without the support of any conventional lithography techniques. The relationships of the flow rate and the diameter of hollow alginate fibers were characterized. It was found that the outer diameter of the alginate hollow fiber was independent of the flow rate, but the core flow and sheath flow played an important role to control the internal diameter and the wall thickness of the alginate hollow microfiber. At a …

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Design, Fabrication And Evaluation Of A Novel Microfluidic Based In Vitro Cell Migration Assay, Sai Sirisha Dhavala Jan 2013

Design, Fabrication And Evaluation Of A Novel Microfluidic Based In Vitro Cell Migration Assay, Sai Sirisha Dhavala

Bioengineering Theses - Archive

Microfabrication and microfluidic devices have been recognized as potential platforms for cell-based and drug screening studies. Human glioblastoma multiforme (hGBM) cells migrate inside the central nervous system (CNS) in narrow space constrictions and rarely metastasize through bloodstream. Hence, microfluidic devices consisting of narrow channels are considered as suitable models to study cell migration in vitro. Further the migratory capability of each individual cell could be easily obtained and quantified using such system. This effort presents the design and development of an alternative microfluidic system that provides an integrated array of channels for screening multiple drugs simultaneously. This system is an …

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Reliable Frontal Cortex Activity For An Oral Stroop Task Using Functional Near Infrared Spectroscopy, Matthew Allen Cloud Jan 2013

Reliable Frontal Cortex Activity For An Oral Stroop Task Using Functional Near Infrared Spectroscopy, Matthew Allen Cloud

Bioengineering Theses - Archive

Analysis tools such as HomER and NIRS-SPM for functional Near-Infrared systems are commercially or freely available; however, they are difficult for clinicians to use as an assessment tool. One barrier to their use is the reliability of a given functional test. Intraclass correlation coefficients (ICC) provide a measure of group and individual reliability. NIRS-SPM was extended with ICC to assess a two part modified Stroop task. The protocol was repeated once every two weeks over a period of one month. Changes in neural activity attributed to inhibition of distraction, show significant covariance to the protocol with moderate to strong reliability …

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Optimized Estimates Based On Multiple Sensor Configuration Knowledge, Roochi Mishra Jan 2013

Optimized Estimates Based On Multiple Sensor Configuration Knowledge, Roochi Mishra

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

There has been an increase in the usage of sensor technology as they are adaptable for use in different environments, many of which are hostile to direct human observation, such as regions affected by land mines or forest fires. The sensors used to monitor developing situations are small inexpensive computing devices with limited processing capabilities, limited power supply and may be destroyed in the event that they are monitoring, without suffering a great financial cost. Also, since these devices are inexpensive, multiple sensors can be deployed for the same application where the sensors are placed or attached to a mobile …

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Mathematical Programming Approaches For Land Use Planning That Limits Urban Sprawl, Piyush Kumar Jan 2013

Mathematical Programming Approaches For Land Use Planning That Limits Urban Sprawl, Piyush Kumar

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Sprawl has a detrimental effect on quality of life and the environment. For example, it increases our dependence on vehicles for daily tasks. This leads to increased vehicular pollution. It also increases traffic, which results in people spending more time on the road. With dwindling resources and increasing population, it becomes necessary that we manage sprawl. Ewing et al. defined factors to measure sprawl in the present urban structure. The measures are divided into four broad categories, which are density factors, mixed use factors, streets factor, and centers factors. These measures address various aspects that contribute to sprawl. For example, …

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Variants Of Multivariate Adaptive Regression Splines (Mars): Convex Vs. Non-Convex, Piecewise-Linear Vs. Smooth And Sequential Algorithms., Diana Luisa Martinez Cepeda Jan 2013

Variants Of Multivariate Adaptive Regression Splines (Mars): Convex Vs. Non-Convex, Piecewise-Linear Vs. Smooth And Sequential Algorithms., Diana Luisa Martinez Cepeda

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Multivariate Adaptive Regression Splines (MARS) is a statistical modeling method used to represent high-dimensional data with interactions. It uses different algorithms to select the terms to be included in the approximation model that best represent the data. In addition, it performs a variable selection, therefore the most significant predictors are shown in the final model. Design and analysis of computer experiments (DACE) is a statistical technique for creating approximations (called metamodels) of computer models. For optimization problems in which there is an unknown function that must be approximated, DACE approach could be applied. In stochastic dynamic programming (SDP) for example, …

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A Model Characterization Of The Texas Healthcare Facilities, Shernette R. Kydd Jan 2013

A Model Characterization Of The Texas Healthcare Facilities, Shernette R. Kydd

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The Patient Protect and Affordable Care Act of 2010 became a law on March 23, 2010. This healthcare act, according to the authors, is designed to improve health services by targeting various facets of the industry: hospitals, private physicians, insurance companies and the drug industry - to name a few. It impacts many people, both directly and indirectly. The effects of this new law will most likely not immediately be recognized, although is it possible for "pockets: of success stories.The administration of Medicare is an area of interest primarily because of the finances involved. Today, there are many waste streams …

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On The Concept Of Earthquake Resistant Hybrid Steel Frames, Seyed Mohammad Razavi Jan 2013

On The Concept Of Earthquake Resistant Hybrid Steel Frames, Seyed Mohammad Razavi

Civil Engineering Dissertations - Archive

The concept of hybrid steel frame system is presented in which mixtures of fully-rigid and semi-rigid steel connections are used in the 3-, 9- and 20-story SAC frames. Several different patterns and locations of semi-rigid connection replacements within the frame are examined in order to identify hybrid frames with the best seismic performance. The effective connection stiffness is identified by performing a parametric study on the initial stiffness of the semi-rigid connections. Then, the cyclic behavior of the connections with the most effective stiffness is obtained using nonlinear finite element analysis. Inelastic dynamic analyses are conducted on the proposed selected …

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An Evaluation Of Models Of Bare Soil Evaporation Formulated With Different Land Surface Boundary Conditions And Assumptions, Kathleen M. Smits, Viet V. Ngo, Abdullah Cihan, Toshihiro Sakaki, Tissa H. Illangasekare Dec 2012

An Evaluation Of Models Of Bare Soil Evaporation Formulated With Different Land Surface Boundary Conditions And Assumptions, Kathleen M. Smits, Viet V. Ngo, Abdullah Cihan, Toshihiro Sakaki, Tissa H. Illangasekare

Civil Engineering Faculty Publications - Archive

Bare soil evaporation is a key process for water exchange between the land and the atmosphere and an important component of the water balance. However, there is no agreement on the best modeling methodology to determine evaporation under different atmospheric boundary conditions. Also, there is a lack of directly measured soil evaporation data for model validation to compare these methods to establish the validity of their mathematical formulations. Thus, a need exists to systematically compare evaporation estimates using existing methods to experimental observations. The goal of this work is to test different conceptual and mathematical formulations that are used to …

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Investigation On Thermo-Mechanical Instability Of Porous Low Dielectric Constant Materials, Emil Hyunbae Zin Dec 2012

Investigation On Thermo-Mechanical Instability Of Porous Low Dielectric Constant Materials, Emil Hyunbae Zin

Material Science and Engineering Dissertations - Archive

This study investigates the structural stability of porous low dielectric constant materials (PLK) under thermal and mechanical load and the influence of contributing factors including porosity as intrinsic factor and plasma damage and moisture absorption as extrinsic factors on thermo-mechanical instability of PLK in advanced Cu/PLK interconnects. For this purpose, a ball indentation creep test technique was developed to examine the thermal and mechanical instability of PLK at relevant load and temperature conditions in the interconnect structure. Our exploration with the ball indentation creep test found that PLK films plastically deforms with time, indicating that viscoplastic deformation does occur under …

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First-Principles Studies On N-Type And P-Type Doping In Cuprous Oxide, Qiong Bai Dec 2012

First-Principles Studies On N-Type And P-Type Doping In Cuprous Oxide, Qiong Bai

Material Science and Engineering Dissertations - Archive

We have performed studies on n-type and p-type cuprous oxide with and without doping by first principles methods. Generalized Gradient Approximation (GGA) is used for the geometry optimization. The total energy and the final electronic structure calculations are conducted using the nonlocal screened Heyd-Scuseria-Ernzerhof (HSE) hybrid density functionals approach for cuprous oxide. The HSE hybrid density functionals overcome the shortcoming of GGA, which gives a much reliable value of the band gap. The formation energies of native point defects in undoped cuprous oxide have been studied by HSE hybrid functional theory in two conditions, which are vacuum based condition and …

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Properties Of Concrete With Tire Derived Aggregate And Crumb Rubber As A Ligthweight Substitute For Mineral Aggregates In The Concrete Mix, Gideon Momanyi Siringi Dec 2012

Properties Of Concrete With Tire Derived Aggregate And Crumb Rubber As A Ligthweight Substitute For Mineral Aggregates In The Concrete Mix, Gideon Momanyi Siringi

Material Science and Engineering Dissertations - Archive

Scrap tires continue to be a nuisance to the environment and this research proposes one way of recycling them as a lightweight aggregate which can substitute for mineral aggregates in concrete. Aggregates derived from scrap tires are often referred to as Tire Derived Aggregate (TDA). First, the focus is how much mineral aggregate can be replaced by these waste tires and how the properties of concrete are affected with the introduction of rubber. This is being mindful of the fact that for a new material to be acceptable as an engineering material, its properties and behavior has to be well …

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Growth Mechanism And Interface Effects On Microstructure Of Perovskite-Type Barium Titanate-Based Epitaxial Films, Jie He Dec 2012

Growth Mechanism And Interface Effects On Microstructure Of Perovskite-Type Barium Titanate-Based Epitaxial Films, Jie He

Material Science and Engineering Dissertations - Archive

This work was motivated and focused on the growth mechanism, microstructures and interfaces of barium titanate, BaTiO3 (BTO), based epitaxial thin films. Transimission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) have been mainly employed in this study for microstructure investigations of BTO-based epitaxial thin films with the assistance of other materials characterization methods, such as X-ray diffraction (XRD), atomic force microscopy (AFM), Nanoindentation testing, etc. As a basic studying model, epitaxial BTO films were first deposited on the (001) MgO substrate using RF magnetron sputtering to provide fundamental knowledge of the film growth for BTO based thin …

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Syntheses, Characterization, And Applications Of Injectable Citrate-Based Mussel-Inspired Biodegradable Adhesive (Icmba) Polymers And Hydrogels, Mohammadreza Mehdizadeh Dec 2012

Syntheses, Characterization, And Applications Of Injectable Citrate-Based Mussel-Inspired Biodegradable Adhesive (Icmba) Polymers And Hydrogels, Mohammadreza Mehdizadeh

Material Science and Engineering Dissertations - Archive

Tissue adhesives are increasingly gaining more popularity in various areas of biomedical applications. They are utilized as surgical adhesives, as a replacement or adjunct to conventional wound closure and bleeding control techniques such as suturing, as well as in other applications such as tissue engineering and drug delivery.Unfortunately, the existing surgical adhesives are not ideal for wet tissue adhesion required in many surgeries such as those for internal organs. Developing surgical adhesives with strong wet tissue adhesion, controlled degradability and mechanical properties, and excellent biocompatibility has been a significant challenge. Herein, learning from nature, we report a one-step synthesis of …

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Auto-Fluorescence Lifetime And Light Reflectance Spectroscopy For Breast Cancer Diagnosis: Potential Tools For Intraoperative Margin Detection, Vikrant Sharma, Shivaranjani Shivalingaiah, Yan Peng, David Euhus, Zygmunt Gryczynski, Hanli Liu Aug 2012

Auto-Fluorescence Lifetime And Light Reflectance Spectroscopy For Breast Cancer Diagnosis: Potential Tools For Intraoperative Margin Detection, Vikrant Sharma, Shivaranjani Shivalingaiah, Yan Peng, David Euhus, Zygmunt Gryczynski, Hanli Liu

Bioengineering Faculty Publications - Archive

This study investigates the use of two spectroscopic techniques, auto-fluorescence lifetime measurement (AFLM) and light reflectance spectroscopy (LRS), for detecting invasive ductal carcinoma (IDC) in human ex vivo breast specimens. AFLM used excitation at 447 nm with multiple emission wavelengths (532, 562, 632, and 644 nm), at which autofluorescence lifetimes and their weight factors were analyzed using a double exponent model. LRS measured reflectance spectra in the range of 500-840 nm and analyzed the spectral slopes empirically at several distinct spectral regions. Our preliminary results based on 93 measured locations (i.e., 34 IDC, 31 benign fibrous, 28 adipose) from 6 …

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Improving Optical Contact For Functional Near-Infrared Brain Spectroscopy And Imaging With Brush Optodes, Bilal Khan, Chester Wildey, Robert Francis, Fenghua Tian, Mauricio R. Delgado, Hanli Liu, Duncan Macfarlane, George Alexandrakis May 2012

Improving Optical Contact For Functional Near-Infrared Brain Spectroscopy And Imaging With Brush Optodes, Bilal Khan, Chester Wildey, Robert Francis, Fenghua Tian, Mauricio R. Delgado, Hanli Liu, Duncan Macfarlane, George Alexandrakis

Bioengineering Faculty Publications - Archive

A novel brush optode was designed and demonstrated to overcome poor optical contact with the scalp that can occur during functional near infrared spectroscopy (fNIRS) and imaging due to light obstruction by hair. The brush optodes were implemented as an attachment to existing commercial flat-faced (conventional) fiber bundle optodes. The goal was that the brush optodes would thread through hair and improve optical contact on subjects with dense hair. Simulations and experiments were performed to assess the magnitude of these improvements. FNIRS measurements on 17 subjects with varying hair colors (blonde, brown, and black) and hair densities (0–2.96 hairs/mm2 ) …

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Sparsity Enhanced Spatial Resolution And Depth Localization In Diffuse Optical Tomography, Venkaiah C. Kavuri, Zi-Jing Lin, Fenghua Tian, Hanli Liu May 2012

Sparsity Enhanced Spatial Resolution And Depth Localization In Diffuse Optical Tomography, Venkaiah C. Kavuri, Zi-Jing Lin, Fenghua Tian, Hanli Liu

Bioengineering Faculty Publications - Archive

No abstract provided.

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Real-Time Detection Of Implant-Associated Neutrophil Responses Using A Formyl Peptide Receptor-Targeting Nir Nanoprobe, Jun Zhou, Tsai Yi-Ting, Hong Weng, Ewin N. Tang, Ashwin Nair, Dave P. Digant, Liping Tang Apr 2012

Real-Time Detection Of Implant-Associated Neutrophil Responses Using A Formyl Peptide Receptor-Targeting Nir Nanoprobe, Jun Zhou, Tsai Yi-Ting, Hong Weng, Ewin N. Tang, Ashwin Nair, Dave P. Digant, Liping Tang

Bioengineering Faculty Publications - Archive

Neutrophils play an important role in implant-mediated inflammation and infection. Unfortunately, current methods which monitor neutrophil activity, including enzyme measurements and histological evaluation, require many animals and cannot be used to accurately depict the dynamic cellular responses. To understand the neutrophil interactions around implant-mediated inflammation and infection it is critical to develop methods which can monitor in vivo cellular activity in real time. In this study, formyl peptide receptor (FPR)-targeting nearinfrared nanoprobes were fabricated. This was accomplished by conjugating near-infrared dye with specific peptides having a high affinity to the FPRs present on activated neutrophils. The ability of FPR-targeting nanoprobes …

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Passive Wireless Antenna Sensors For Crack Detection And Shear/Compression Sensing, Irshad Mohammad Jan 2012

Passive Wireless Antenna Sensors For Crack Detection And Shear/Compression Sensing, Irshad Mohammad

Mechanical and Aerospace Engineering Dissertations - Archive

Despite the fact that engineering components and structures are carefully designed against fatigue failures, 50 to 90% of mechanical failures are due to fatigue crack formation. The severity of the failure depends on both the crack length and its orientation with respect to the loading direction. Many types of sensors are available that can detect fatigue crack propagation. But, crack orientation detection has been rarely reported in the literature. We evaluated a patch antenna sensor capable of detecting crack propagation as well as crack orientation changes. The aim of the sensors would be to evaluate the real-time health condition of …

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Illustration Of Fundamentals Of Mechanical Vibration Using Computable Document Format, Shiva Deshmukh Jan 2012

Illustration Of Fundamentals Of Mechanical Vibration Using Computable Document Format, Shiva Deshmukh

Mechanical and Aerospace Engineering Theses - Archive

The main objective of this study is focused on the better understanding of the basic concepts of mechanical vibrations and its free and ready availability to the entire student community all over the globe.In this study the concepts of vibrations are projected in the form of mathematical models. The mathematical models are designed using MATHEMATICA. These models are graphical in nature and can be animated at will. They are compiled and converted to the Computable Document Format referred as CDF.A very special function Manipulate is used in making the models. This function has given the models an ability to compute …

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Photoelectrochemical Activity Of Titanium Dioxide Thin Films, Aida Mehdinezhad Roshan Jan 2012

Photoelectrochemical Activity Of Titanium Dioxide Thin Films, Aida Mehdinezhad Roshan

Material Science and Engineering Theses - Archive

Titanium dioxide (TiO2) is considered as an oxide semiconductor with several unique properties, including environmental sensing capabilities, biocompatibility and photocurrent generation, long-term stability, cost efficiency, and chemical inertness. TiO2 thin films have a wide range of applications in dye-sensitized solar cells. TiO2 films have been deposited on two different substrates, aluminum and titanium. Two different methods used for deposition of the thin films namely: Plasma Electrolytic Oxidation (PEO) and Physical Vapor Deposition (PVD). In order to study the effect of roughness of the substrate on photocurrent generation of the deposited films, one group of substrates were “patterned” by Electrolytic Plasma …

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Graph Theoretic Framework Based Cooperative Control And Estimation Of Multiple Uavs For Target Tracking, Mousumi Ahmed Jan 2012

Graph Theoretic Framework Based Cooperative Control And Estimation Of Multiple Uavs For Target Tracking, Mousumi Ahmed

Mechanical and Aerospace Engineering Dissertations - Archive

Designing the control technique for nonlinear dynamic systems is a significant challenge. Approaches to designing a nonlinear controller are studied and an extensive study on backstepping based technique is performed in this research with the purpose of tracking a moving target autonomously. Our main motivation is to explore the controller for cooperative and coordinating unmanned vehicles in a target tracking application.To start with, a general theoretical framework for target tracking is studied and a controller in three dimensional environment for a single UAV is designed. This research is primarily focused on finding a generalized method which can be applied to …

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Lumped Parameter Modeling Of Fluid Line Dynamics With Turbulent Flow Conditions, Yi-Wei Huang Jan 2012

Lumped Parameter Modeling Of Fluid Line Dynamics With Turbulent Flow Conditions, Yi-Wei Huang

Mechanical and Aerospace Engineering Dissertations - Archive

A procedure for obtaining rational polynomial transfer functions representing ordinary differential equations for time domain transient response simulations of systems with fluid transmission lines with incompressible turbulent flow is formulated and presented. The method is based on the use of an inverse frequency least squares algorithm applied to the distributed parameter model for laminar flow with added lumped resistance to match the additional resistance associated with turbulence. Guidelines for using the algorithm are included with focus on the use of weighting parameters, the number of resonant modes to be included, and the bandwidth of the pressure/flow pulsation dynamics in the …

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Computer Simulation, Fabrication And Characterization Of Inverse Frustum Nanosphere Metal Arrays For Fiber-Based Plasmonic Sensors, Jiaqi Wu Jan 2012

Computer Simulation, Fabrication And Characterization Of Inverse Frustum Nanosphere Metal Arrays For Fiber-Based Plasmonic Sensors, Jiaqi Wu

Material Science and Engineering Theses - Archive

In recent years, a number of metal nanostructures have attracted huge attention from scientists and researchers for its plasmonic property and surface enhanced Raman scattering effect. They have been utilized to monitor molecule adsorption, antibody-antigen reorganization event, and to enhance scattering for identification of molecules even in very low concentration. They both have also been exploited for real time biosensing.In this thesis, we are investigating a new plasmonic structure, inverse frustum nanosphere gold arrays, and exploring its optical fiber-based sensing application. The nanostructure was fabricated by electro-deposition of gold into pre-assembled templates, which are made of monodispered colloidal polystyrene nanospheres …

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