Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

2012

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 4111 - 4140 of 6304

Full-Text Articles in Engineering

Torsional Analysis Of A Composite I-Beam, Vishal Mukesh Smita Sanghavi Jan 2012

Torsional Analysis Of A Composite I-Beam, Vishal Mukesh Smita Sanghavi

Mechanical and Aerospace Engineering Theses - Archive

A simple methodology for analysis of thin walled composite I-Beam subjected to free torsion and restrained torsion is developed. Classical Lamination Theory is extended from the laminate level to the structural level for analysis purpose.The developed expressions for shear center, equivalent torsional rigidity and equivalent warping rigidity for a composite mono-symmetric I-Beam depends on the material properties, ply stacking sequence, fiber orientation and geometryThe results from the proposed theory gives better agreement with the ANSYSTM results than the traditional smeared property approach.

Go to article

Control Of A Teleoperating Robotic Arm Subject To Time Delays, Pankaj Prakash Sarda Jan 2012

Control Of A Teleoperating Robotic Arm Subject To Time Delays, Pankaj Prakash Sarda

Mechanical and Aerospace Engineering Theses - Archive

Robotics in Minimally Invasive Surgeries (MIS) can be explored to its full potential if there is complete transparency between the surgeon and the virtual environment. In the setup, haptic device which conveys force from the surgeon to the surgery site and vice verse acts as the master station and robotic arm at the surgery site acts as the slave robot. In surgeries carried out remotely, time delays in the communication channels can cause commanded velocity/force to overshoot before the surgeon can even pull out during a task causing temporary or permanent damage during the surgery. Since the physical capability of …

Go to article

Study Of The Surface Roughness Evolution In Fatigued 316l Stainless Steel, Ye Wang Jan 2012

Study Of The Surface Roughness Evolution In Fatigued 316l Stainless Steel, Ye Wang

Mechanical and Aerospace Engineering Theses - Archive

Fatigue is a critical design consideration in many aerospace structures. As improvements are sought in overall performance, maintenance requirements, and total service life of modern aircrafts, the demands for fatigue control techniques, such as material design for fatigue resistance, reliable fatigue life prediction, and continuous material damage monitoring, have increased. The most common practices to ensure fatigue safety include: fracture mechanics based fatigue life prediction, periodic non-destructive inspections, and material processing control. Reasonable successes have been achieved by applying these three techniques to ensure the safe operation of aerospace structures. It is worth mentioning that most of the present fatigue …

Go to article

New Developments In Cognitive Optimization, Parvati Aruna Kandala Jan 2012

New Developments In Cognitive Optimization, Parvati Aruna Kandala

Mechanical and Aerospace Engineering Theses - Archive

This work presents an approach to solve function optimization problems using cognitive optimization. A cognitive search algorithm which is developed mimics human cognition in structure and characteristics. This algorithm is developed based on the key aspects of a cognitive system, namely, the use of prior knowledge, communication, and self-organization. The processes have the knowledge of how to solve the optimization problems from traditional techniques such as bracketing, gradient search and interval-halving methods. This search algorithm shows that, by passing messages, the processes communicate, share information, and self-organize around the solution. A mat lab program is coded to perform the tests …

Go to article

Transient Analysis Of A Pulsed Detonation Combustor Using The Numerical Propulsion System Simulation, Anthony Scott Hasler Jan 2012

Transient Analysis Of A Pulsed Detonation Combustor Using The Numerical Propulsion System Simulation, Anthony Scott Hasler

Mechanical and Aerospace Engineering Theses - Archive

The performance of a hybrid mixed flow turbofan (with detonation tubes installed in the bypass duct) is investigated in this study and compared with a baseline model of a mixed flow turbofan with a standard combustion chamber as a duct burner. Previous studies have shown that pulsed detonation combustors have the potential to be more efficient than standard combustors, but they also present new challenges that must be overcome before they can be utilized. The Numerical Propulsion System Simulation (NPSS) will be used to perform the analysis with a pulsed detonation combustor model based on a numerical simulation done by …

Go to article

Analytical Method For Analyzing C-Channel Stiffener Made Of Laminate Composite, Tattchapong Kumton Jan 2012

Analytical Method For Analyzing C-Channel Stiffener Made Of Laminate Composite, Tattchapong Kumton

Mechanical and Aerospace Engineering Theses - Archive

Composite materials play the important role in the aviation industry. Conventional materials such as aluminum were replaced by composite material on the main structures. The objective of this study focuses on development of analytical method to analyze the laminated composite structure with C-channel cross-section. A lamination theory base closed-form solution was developed to analysis ply stresses on the C-channel cross-section. The developed method contains the effects of coupling due to unsymmetrical of both laminate and structural configuration levels. The present method also included the expression of the sectional properties such as centroid, axial and bending stiffnesses of cross-section. The results …

Go to article

Particle Advection Using The Lattice-Boltzmann Method, Matthew Carroll Jan 2012

Particle Advection Using The Lattice-Boltzmann Method, Matthew Carroll

Mechanical and Aerospace Engineering Theses - Archive

Lattice-Boltzmann Method (LBM) CFD analysis can be helpful in analysing fluid flow through porous media and complex geometries that may be difficult to simulate using traditional CFD methods. In this thesis, the technical details of lattice Botlzmann particle advection are presented. The lattice Botlzmann equations are explained as well as a method for introducing a particle in a fluid flow and advecting the particle using viscous, pressure, and gravitational forces. A method is developed to advect a particle through a computational lattice mesh using pressure forces, gravitational forces, as well as LBM-specific viscous force equations. The capability of the particle …

Go to article

Stress Concentrations Around A Square Cutout In A Composite Plate, Colin Cannon Jan 2012

Stress Concentrations Around A Square Cutout In A Composite Plate, Colin Cannon

Mechanical and Aerospace Engineering Theses - Archive

Composite structure in the aircraft industry has been in development for well over half a century and yet the understanding of the effects of a square cutout is generally limited to quasi-isotropic laminates. Currently, the closed-form solution to calculate the stresses around a cutout is limited to symmetric anisotropic laminates with limitations on the cutout shapes. Finite Element Analysis, using MSC PATRAN and NASTRAN, was performed on 2D composite laminates containing square cutouts with rounded corners. The laminate stacking sequence was varied from symmetrical and balanced to unsymmetrical and unbalanced and the square cutouts each had different radii at the …

Go to article

Cfd Based Aerodynamic Modeling To Study Flight Dynamics Of A Flapping Wing Micro Air Vehicle, Alok Ashok Rege Jan 2012

Cfd Based Aerodynamic Modeling To Study Flight Dynamics Of A Flapping Wing Micro Air Vehicle, Alok Ashok Rege

Mechanical and Aerospace Engineering Theses - Archive

The demand for small unmanned air vehicles, commonly termed micro air vehicles or MAV's, is rapidly increasing. Driven by applications ranging from civil search-and-rescue missions to military surveillance missions, there is a rising level of interest and investment in better vehicle designs, and miniaturized components are enabling many rapid advances. The need to better understand fundamental aspects of flight for small vehicles has spawned a surge in high quality research in the area of micro air vehicles. These aircraft have a set of constraints which are, in many ways, considerably different from that of traditional aircraft and are often best …

Go to article

Impact Of Louver Orientation On Air Flow Distribution And Thermal Management Of Data Centers, Kushal A. Aurangabadkar Jan 2012

Impact Of Louver Orientation On Air Flow Distribution And Thermal Management Of Data Centers, Kushal A. Aurangabadkar

Mechanical and Aerospace Engineering Theses - Archive

Nowadays with the increasing use of technology, Traditional data centers are being replaced by the highly efficient Containerized or Modular Data centers. The cooling systems and constructional cost employed for Traditional Data centers is more and inefficient. The research intricate, about 23% of the power is consumed by HVAC cooling units and which in turn leads to increase in operational costs. Hence in order to reduce the operational costs, free cooling with Air side economizer is incorporated, compared to other cooling systems. Airflow Distribution plays an important role in the Thermal management, if the airflow is less in quantity it …

Go to article

Assessment Of The Mechanical Integrity Of Cu/Low-K Dielectric In A Flip Chip Package, Thiagarajan Raman Jan 2012

Assessment Of The Mechanical Integrity Of Cu/Low-K Dielectric In A Flip Chip Package, Thiagarajan Raman

Mechanical and Aerospace Engineering Theses - Archive

Miniaturization and more recently convergence have been driving the industry since the invention of the transistor and integrated circuit (IC). Though the gate delay has decreased with transistor scaling, the increase in the resistive capacitive (RC) interconnect delay due to shrinking interconnect dimensions has become a serious concern for the development of future-generation electronics. To reduce the delay due to resistance R, a major technology change was the replacement of Aluminum (Al) with Copper (Cu) interconnect layers in the BEoL (Back-end-of-line). Recently, some investigators have suggested using low-k dielectric (having dielectric constant less than 4) instead of SiO2 (k= 3.9) …

Go to article

Numerical Study Of Sidewall Filling For Gas-Fed Pulse Detonation Engines, Wunnarat Rongrat Jan 2012

Numerical Study Of Sidewall Filling For Gas-Fed Pulse Detonation Engines, Wunnarat Rongrat

Mechanical and Aerospace Engineering Theses - Archive

Pulse detonation engines for aerospace propulsion are required to operate at 50-100 Hz meaning that each pulse is 10-20 ms long. Filling of the engine and the related purging process become dominant due to their long duration compared to ignition and detonation wave propagation. This study uses ANSYS FLUENT to investigate the filling of a 1 m long tube with an internal diameter of 100 mm. Six different configurations were investigated with an endwall port and various sidewall arrangements, including stagger and inclination. A stoichiometric mixture of gaseous octane and air at STP was used to ll the tube at …

Go to article

Thermal Analysis Of High End Servers Based On Development Of Detail Model And Experiments, Shreyas Sampath Jan 2012

Thermal Analysis Of High End Servers Based On Development Of Detail Model And Experiments, Shreyas Sampath

Mechanical and Aerospace Engineering Theses - Archive

Thermal management of an efficient data center can be primarily dictated by efficient servers. Continued increase in power density and power dissipation of high end processors, thermal analysis and management has made it strategically important in the challenge of advanced thermal solutions. Present day CFD software provides powerful tools to create very accurate fluid and heat transfer solutions. Validation of a detailed model of a server in CFD corresponds to accurate flow and temperature models and these detailed server models are the foundational blocks for accurate data center thermal management solutions. In this research, an experimental study of the thermal …

Go to article

Performance Evaluation And Finite Element Analysis Of Fiber Reinforced Precast Concrete Underground Structures, Ashley Wilson Jan 2012

Performance Evaluation And Finite Element Analysis Of Fiber Reinforced Precast Concrete Underground Structures, Ashley Wilson

Civil Engineering Theses - Archive

This study aimed at evaluating the performance of BASF Synthetic and Steel fibers as alternative reinforcements in concrete pipes. A total of 93 synthetic fiber and 60 steel fiber reinforced pipes were produced and tested based on the ASTM C497 in order to have a benchmark for comparison with conventionally reinforced concrete pipes. Three production sites with different production equipment were used in different geographical locations in the United States. Standard ASTM C76 diameters of up to 36 in. with "Wall-B" and "Wall-C" were used in this study for both synthetic and steel fibers. Vertical and horizontal load-deformation plots for …

Go to article

Engineering Behavior Of Lime Treated High Sulfate Soils, Ahmed Hassan Mohamed Gaily Jan 2012

Engineering Behavior Of Lime Treated High Sulfate Soils, Ahmed Hassan Mohamed Gaily

Civil Engineering Theses - Archive

Regardless of increased knowledge and awareness of sulfate heave, the Texas Department of Transportation (TxDOT) continues to experience pavement failures during and immediately after construction on transportation infrastructures intended to last at least 20 years. Failures are predominantly observed in sites where high sulfate soils of 8,000 ppm or higher levels. Many of these failures are attributed to sulfate-induced heave where an expansive mineral called Ettringite is formed from calcium-based stabilizers (lime or cement) reacting with water, clay, and sulfates. The reactions responsible for Ettringite formation are extremely complex which make generalizations concerning the rate and magnitude of heaving in …

Go to article

Comparative Application Of Two Nanoparticles In Cement Mortar, Vinoth Mohanam Jan 2012

Comparative Application Of Two Nanoparticles In Cement Mortar, Vinoth Mohanam

Civil Engineering Theses - Archive

Carbon Nanotubes (CNTs) and Carbon Nanofibers (CNFs) are two of the most promising advanced materials in the construction industry due to their excellent material properties. In this study, their application in cement mortar is studied comparatively as possible choice for concrete repair. CNT and CNF have very high aspect ratio due to which the Van der Wal forces between the CNT and CNF tend to agglomerate; thus forming bundles. In order to achieve proper dispersion, ultrasonic energy was used to disperse the CNT and CNF in the aqueous solution. The mechanical properties such as compressive strength and flexural strength of …

Go to article

The Effects Of Climate, Soil, And Vegetation On The Design Of Water Balance Covers For Solid Waste Landfills In Texas, Salman Baig Jan 2012

The Effects Of Climate, Soil, And Vegetation On The Design Of Water Balance Covers For Solid Waste Landfills In Texas, Salman Baig

Civil Engineering Theses - Archive

The purpose of this study is to determine the effects of climate, soil, and vegetation on the design of water balance (WB) covers for solid waste landfills in Texas. This study was conducted using water balance software (UNSAT-H model) that considers unsaturated soil hydraulics and plant water uptake. To date, limited research has been conducted for WB covers in Texas. Texas is located in the central region of the United States and encounters approximately nine distinct 5 inch precipitation increments or ranges, unlike any other state in the United States. Texas includes various climate regions and is a favorable choice …

Go to article

Effect Of Saline Water On Landfill Gas Generation Of Municipal Solid Waste, Yogavathani Sivanesan Jan 2012

Effect Of Saline Water On Landfill Gas Generation Of Municipal Solid Waste, Yogavathani Sivanesan

Civil Engineering Theses - Archive

The Enhanced Leachate Recirculation (ELR) landfills operation results in rapid waste stabilization, waste decomposition and increased rate of gas generation. However, operating landfill as an ELR landfill requires availability of sufficient amount of fresh water in close proximity to the landfill facility. In coastal regions, where fresh water supplies may be scarce, available saline water may be considered for ELR operation. However, the effects of saline water on the decomposition solid waste and landfill gas generation are unknown and need to be investigated., The objectives of the current research are to investigate the effects of adding and/or recirculating saline water …

Go to article

Identifying Issues Impacting Productivity Of Box Jacking Projects, Bhaumi Bhavan Chaurasia Jan 2012

Identifying Issues Impacting Productivity Of Box Jacking Projects, Bhaumi Bhavan Chaurasia

Civil Engineering Theses - Archive

Jacking is a trenchless construction technique used for installing underground pipeline system. Jacking method is more widely used for upgrading under capacity culverts and drainage structures under roads and railroad tracks. Also, this method is used for installing underground pipelines such as watermains, sewers etc.in populated and developed urban areas. In this method, culverts (segments) are installed through the ground from an entry shaft to an exit shaft. During the excavation and spoil removal processes, workers are required to be inside the pipe, this is essentially what separates pipe jacking trenchless construction method from microtunneling technology. The minimum recommended diameter …

Go to article

Effect Of Nano Zero Valent Iron On Degradation Of Municipal Solid Waste In Bioreactor Landfills, Meenakshi Gangopadhyay Jan 2012

Effect Of Nano Zero Valent Iron On Degradation Of Municipal Solid Waste In Bioreactor Landfills, Meenakshi Gangopadhyay

Civil Engineering Theses - Archive

Nanotechnology has substantial potential for reducing contamination, toxicity and overall human health hazards and environmental risks. In recent times, nano zero valent iron has proved to be effective in contaminant reduction and pollution control. Iron is an important micronutrient for the microbes involved in the anaerobic decomposition of solid waste in bioreactor landfills. Landfill leachate sometimes contains toxic compounds which nano zero valent iron has proven to be very effective in removing, particularly chlorinated organics, heavy metals, and odorous sulfides. Iron can also potentially increase landfill methane generation by removing long chain fatty acids and sulfides that inhibit methanogenesis.nZVI materials …

Go to article

Investigations Into Causes Of Failure Of Regenerative Peripheral Nerve Interfaces, R. Collins Watson Jan 2012

Investigations Into Causes Of Failure Of Regenerative Peripheral Nerve Interfaces, R. Collins Watson

Bioengineering Dissertations - Archive

All highly selective methods of neural interfacing for mental control of a robotic prosthesis tested to date have exhibited high rates of failure over time. Regenerative peripheral nerve interfaces (RPNIs) may offer the greatest potential among the proposed technologies for providing the number of degrees of freedom necessary to control a robotic limb, but are unacceptable for clinical use due to several shortcomings of current technology: (1) all RPNIs tested to date have exhibited signal loss over time due to biological mechanisms of rejection of implanted electrodes; (2) all chronically tested interfaces have suffered from high rates of device failure …

Go to article

Pleiotrophin Enhance Nerve Regeneration Across Long Gap Peripheral Nerve Defects, Swarup Narayan Dash Jan 2012

Pleiotrophin Enhance Nerve Regeneration Across Long Gap Peripheral Nerve Defects, Swarup Narayan Dash

Bioengineering Dissertations - Archive

Peripheral nerve injuries resulting in extensive loss in nerve continuity pose a challenge in reconstructive surgery. Autografts still remain the treatment of choice for nerve defects despite the need of donor nerve harvest and the associated morbidity of this procedure. In contrast to short gap injuries, isografts achieve sub normal functional recovery for gaps longer than a critical 30 mm length, and simple tubularization methods fail completely. The regenerative failure of peripheral nerves through long gaps can be postulated to the lack of appropriate growth substrate and trophic support. We hypothesize that for successful nerve regeneration across long-gap nerve defects, …

Go to article

An Investigation Of Pipe Jacking Loads In Trenchless Technology, Saeed Rahjoo Jan 2012

An Investigation Of Pipe Jacking Loads In Trenchless Technology, Saeed Rahjoo

Civil Engineering Theses - Archive

Pipe jacking is a trenchless technology method of installing pipes under existing facilities such as roads and railroads. Predicting jacking forces is important for planning, design, and construction phases of these projects. The jacking forces dictate shaft or pit locations, thrust block or backstop design, jacking equipment, use of intermediate jacking stations, and pipe bearing capacity. Calculating jacking forces depends on several site and project parameters such as soil and site conditions, lubrication, size of overcut, and steering corrections. Excessive jacking forces can damage the pipe and destabilize the drive shaft, which may stop project progress. There are different methods …

Go to article

Performance Of Large Diameter Polyvinyl Chloride (Pvc) Pipes In Water Applications, Pradip P. Deshmukh Jan 2012

Performance Of Large Diameter Polyvinyl Chloride (Pvc) Pipes In Water Applications, Pradip P. Deshmukh

Civil Engineering Theses - Archive

Polyvinyl chloride (PVC) pipes with diameters greater than 24" make up a small fraction of water utilities. Most of the research done on PVC pipes in water utilities focuses on diameters less than 24". Therefore, this thesis focuses on PVC water main pipelines with a diameter greater than 24" in an attempt to understand their performance in the water management facilities. This thesis had several objectives, such as to evaluate 24" and larger diameter PVC pipes in water transmission and distribution applications, calculate failure rate per hundred miles of PVC pipes at water utilities, categorize age of PVC pipelines with …

Go to article

Magnetic-Based Theranostic Nanoparticles For Prostate Cancer Management, Aniket Sharadrao Wadajkar Jan 2012

Magnetic-Based Theranostic Nanoparticles For Prostate Cancer Management, Aniket Sharadrao Wadajkar

Bioengineering Dissertations - Archive

With an increasing rate of cancers, the need for effective cancer management has led to the development of theranostic systems for diagnosis and therapy. Conventional techniques for cancer management have limited success due to inaccurate diagnosis and treatment side effects. Development of magnetic-based theranostic nanoparticles (MBTN) may overcome these limitations with the advantages of magnetic nanoparticles (MNPs) such as magnetic targeting, hyperthermia, and magnetic resonance imaging (MRI) contrast agents; and advantages of polymer coatings for carrying payloads and allowing bioconjugation for active targeting applications. Aim of this research was to develop multifunctional MBTNs for prostate cancer management. First, biodegradable photoluminescent …

Go to article

Long-Term Performance Of Gfrp Reinforced Concrete Beams And Bars Subjected To Aggressive Environments, Yeonho Park Jan 2012

Long-Term Performance Of Gfrp Reinforced Concrete Beams And Bars Subjected To Aggressive Environments, Yeonho Park

Civil Engineering Dissertations - Archive

The use of fiber-reinforced polymer (FRP) bars in reinforced concrete (RC) structures has emerged as an alternative to traditional steel reinforcement environments and other applications where steel has shown greater vulnerability. Although the number of analytical and experimental studies on RC beams with FRP reinforcement has increased in recent decades, its long term performance is still questioned in comparison to the traditional steel reinforcement. That is, long-term performance is a much recognized but less-mentioned topic in the field of the reinforced concrete with glass-FRP (GFRP) re-bars. There is a need to validate long-term performance of FRP reinforced concrete structures, and …

Go to article

A Novel Minimally Invasive Dual-Modality Fiber Optic Probe For Prostate Cancer Detection, Vikrant Sharma Jan 2012

A Novel Minimally Invasive Dual-Modality Fiber Optic Probe For Prostate Cancer Detection, Vikrant Sharma

Bioengineering Dissertations - Archive

Prostate cancer is the most common form of cancer in males, and is the second leading cause of cancer related deaths in United States. In prostate cancer diagnostics and theapy, there is a critical need for a minimally invasive tool for in vivo evaluation of prostate tissue. Such a tool finds its niche in improving TRUS (trans-rectal ultrasound) guided biopsy procedure, surgical margin assessment during radical prostatectomy, and active surveillance of patients with a certain risk levels. This work is focused on development of a fiber-based dual-modality optical device (dMOD), to differentiate prostate cancer from benign tissue, in vivo. dMOD …

Go to article

Methodology Of Citric Acid Based Functional Biomaterial Development And Application, Yi Leaf Zhang Jan 2012

Methodology Of Citric Acid Based Functional Biomaterial Development And Application, Yi Leaf Zhang

Bioengineering Dissertations - Archive

Biomaterials play critical roles in modern strategies of biomedical applications, such as tissue engineering, and theranostic therapy. Attempts to design ideal biomaterials for each specific application have led to an enormous increase in the number of polymeric biomaterials. Different biomedical applications require specific functionality of biomaterials. Unfortunately, the limited versatility of currently available biodegradable polymers fails to meet the wide range of requirement for biomedical applications. Therefore, a methodology of functional biomaterials development would be beneficial to the biomaterial field. It has been proved that citric acid can be utilized as a key element in the development of novel biodegradable …

Go to article

Phase Sensitive Spectral Domain Interferometry For Label Free Biomolecular Interaction Analysis And Biosensing Applications, Sajal Chirvi Jan 2012

Phase Sensitive Spectral Domain Interferometry For Label Free Biomolecular Interaction Analysis And Biosensing Applications, Sajal Chirvi

Bioengineering Dissertations - Archive

Biomolecular interaction analysis (BIA) plays vital role in wide variety of fields, which include biomedical research, pharmaceutical industry, medical diagnostics, and biotechnology industry. Study and quantification of interactions between natural biomolecules (proteins, enzymes, DNA) and artificially synthesized molecules (drugs) is routinely done using various labeled and label-free BIA techniques. Labeled BIA (Chemiluminescence, Fluorescence, Radioactive) techniques suffer from steric hindrance of labels on interaction site, difficulty of attaching labels to molecules, higher cost and time of assay development. Label free techniques with real time detection capabilities have demonstrated advantages over traditional labeled techniques. The gold standard for label free BIA is …

Go to article

Dynamic Bus Lane, Isaac F. Joskowicz Jan 2012

Dynamic Bus Lane, Isaac F. Joskowicz

Civil Engineering Dissertations - Archive

This dissertation documents the research conducted to investigate the feasibility of implementing a "Dynamic Bus Lane" (DBL) system on Westheimer Road in Houston, Texas, and to determine the particular conditions when the system could be applied to other arterial streets. The DBL system is a bus preferential system which would turn a normal traffic lane into a bus lane when a bus is approaching a bus stop at a major intersection. The bus would activate a dynamic message sign that would change the lane use from a normal traffic lane to a bus lane for the time when the bus …

Go to article

First Prev Next Last