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Full-Text Articles in Engineering

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer Jan 2011

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer

LSU Master's Theses

Gas turbine blade tips experience very high thermal loads due to high temperature combustion gases and tip leakage flows. This leads to the tip region being very susceptible to experiencing failures. To better understand these effects, experiments were performed in a suction-type low speed wind tunnel cascade to determine heat transfer coefficients and film cooling effectiveness distributions on a highly-loaded 2-D gas turbine blade model in the tip and near-tip regions. The blade shape was generated to match the pressure coefficients of the operating turbine blade design. The model featured multiple tip and pressure side film cooling holes and a …


Discrete Element Modeling Of Cone Penetration In Jsc-1a Lunar Regolith Simulant, Mehmet Burak Cil Jan 2011

Discrete Element Modeling Of Cone Penetration In Jsc-1a Lunar Regolith Simulant, Mehmet Burak Cil

LSU Master's Theses

NASA plans to return back to the Moon for a long term presence and use of the Moon as a launch station for further space exploration to other planets. This scenario increases the importance of determining the geotechnical properties of the lunar surface. However, due to the limited availability of lunar regolith and its high scientific value, a simulant material which closely matches the composition and grain size distribution and other characteristics of the lunar regolith has become an indispensable need to benefit in hardware development as well as estimating lunar regolith properties. Therefore, JSC-1A lunar regolith simulant, which was …


V2o5-Wo3 Composite Films And Surface-Coated Licoo2 For Enhanced Li-Ion Intercalation Properties, Chuan Cai Jan 2011

V2o5-Wo3 Composite Films And Surface-Coated Licoo2 For Enhanced Li-Ion Intercalation Properties, Chuan Cai

LSU Master's Theses

We have investigated the enhanced Li-ion intercalation properties of two different materials, which are V2O5-WO3 composite and surface-coated LiCoO2. A simple and novel solution processing method is employed to prepare V2O5-WO3 composite films that demonstrate enhanced Li-ion intercalation properties for applications in Li-ion batteries or electrochromic displays. This solution processing method employs precursors that only contain the elements of V, W, O and H, which avoids impurity elements such as Na that has been commonly used in other solution methods (e.g. using precursors of sodium metavanadate and sodium tungstate solution). The V2O5-WO3 composite films show enhanced Li-ion intercalation properties compared …


Performance Assessment Of Innovative Framing Systems Through Building Information Modeling Based Energy Simulation, Santhosh Reddy Chinnayeluka Jan 2011

Performance Assessment Of Innovative Framing Systems Through Building Information Modeling Based Energy Simulation, Santhosh Reddy Chinnayeluka

LSU Master's Theses

While many residential contractors, architects, and home-buyers today are concerned about the environment and interested in sustainable construction technologies, the perceived higher initial costs of innovative materials and methodologies and a lack of life-cycle cost and performance data present significant barriers in the implementation of such techniques. Research regarding an integrated design process has suggested that performance based decision making is key to the successful implementation of sustainable building practices. Therefore, a need exists for the development of whole building design and evaluation models to allow decision making in all phases of a building project. This research seeks information regarding …


Development And Implementation Of A Dual-Porosity Pore Network Structure Using X-Ray Computed Tomography For Pore Network Modeling Purposes, Samuel Taylor Best Jan 2011

Development And Implementation Of A Dual-Porosity Pore Network Structure Using X-Ray Computed Tomography For Pore Network Modeling Purposes, Samuel Taylor Best

LSU Master's Theses

3-D pore network modeling based on high-resolution X-ray computed tomography (XCT) is a useful tool for simulating pore-scale processes and phenomena within porous media in fields such as chemical and petroleum engineering and groundwater hydrology. XCT images provide the opportunity to capture the true topology of the porous system, retaining important characteristics such as pore geometry, location, and connectivity. However, a major limitation of XCT is its inability to resolve features smaller than the image resolution such as intraparticle porosity and void-space within secondary phases such as clay and micrite, here called microporosity. Identifying this microporosity is important for modeling …


Simulation Of Cell Seeding And Retention In A Disordered Polymeric Scaffold, Tejaswini Narayana Jan 2011

Simulation Of Cell Seeding And Retention In A Disordered Polymeric Scaffold, Tejaswini Narayana

LSU Master's Theses

Historically, bone repair has been performed using materials like metals, ceramics, cements and bioactive glass. The major problem with all these materials is that they do not perform the necessary non-structural functions of bone. Engineered tissue, created by growing bone cells on porous biodegradable material (scaffold), will address this issue with current bone repair techniques. Improving engineered tissue treatments requires a thorough understanding of factors affecting cell seeding and proliferation inside a disordered porous material which is not feasible using current experimental techniques. A model for particle transport in a disordered porous material that can predict the particle deposition pattern …


Hydrodynamic Focusing Micropump Module With Pdms/Nickel-Particle Composite Diaphragms For Microfluidic Systems, Jeonghwan Kim Jan 2011

Hydrodynamic Focusing Micropump Module With Pdms/Nickel-Particle Composite Diaphragms For Microfluidic Systems, Jeonghwan Kim

LSU Master's Theses

In this research, a rapid prototype of multi-fluidic speed-modulating (MFSM) micropump which enables modulation of hydrodynamic focusing in micro-fluidic flow has been designed, fabricated, and characterized. The size of the entire module is 33 mm x 25 mm x 8 mm and comprises of three MFSM micropumps to achieve hydrodynamic focusing. These pumps are simultaneously operated by the same actuation source. Each micropump consists of Tesla-type valves in the bottom layer and PDMS/Ni-particle composite (PNPC) diaphragm in the middle layer. The deflection of the diaphragm is obtained by the external pneumatic force, and the permanent magnet controls the displacement resulting …


Electrochemical Etching Of Isolated Structures In P-Type Silicon, Joel Nino Bugayong Jan 2011

Electrochemical Etching Of Isolated Structures In P-Type Silicon, Joel Nino Bugayong

LSU Master's Theses

The role of the space charge region (SCR) was demonstrated in isolated structures for the first time. Electrochemical etching was conducted in differently pitched structures in p-type silicon. A design of experiment was also performed to evaluate the effect of electrolyte and applied potential. Finally chemical etching was demonstrated as a possible post-etch clean to porous structures. The results showed that the morphology of etched structures in pre-patterned silicon is strongly influenced by the SCR even in isolated structures. Using lightly-doped p-type Si (1,000-10,000 Ω-cm), deep macropores were obtained in wide-pitched patterns. However, the diameter of the pores grew larger …


Wave Forces On Bridge Decks And Damping Techniques To Reduce Damages, Aaron Michael Henry Jan 2011

Wave Forces On Bridge Decks And Damping Techniques To Reduce Damages, Aaron Michael Henry

LSU Master's Theses

The population of the Gulf Coast has grown immensely since 1960. Bridges along the coast are a vital part of this area’s infrastructure. They impact the transportation of goods and services, as well as the tourism in these areas. Many of these coastal bridges are at risk of being damaged or even destroyed during extreme weather events. This can cause not only short and long-term monetary problems, but the damage also can exacerbate the issues in getting people out of dangerous areas and getting help into areas in need, after an event. Damages during extreme weather events are the result …


Investigations Of Wave-Induced Turbulent Structures In Vegetated Flows, Agnimitro Chakrabarti Jan 2011

Investigations Of Wave-Induced Turbulent Structures In Vegetated Flows, Agnimitro Chakrabarti

LSU Master's Theses

The role of coastal vegetation in mitigating shoreline erosion by damping of incoming waves and the resultant effect on sediment transport is a critical area of coastal management research. However our understanding of the underlying hydrodynamic processes is limited. Laboratory flume experiments were conducted where a naturally grown emergent vegetation channel and a vegetation-less sand channel were exposed to regular waves. Wave height data was collected using wave gauges located at various points along the channel in the direction of oncoming waves. Acoustic Doppler Velocimeters (ADVs) placed at various depths in the water column measured wave orbital velocity signatures. This …


The Stereospecific Hydrogenation And Dehydrogenation Of Rosin And Fatty Acids, Edward O'Brien Jan 2011

The Stereospecific Hydrogenation And Dehydrogenation Of Rosin And Fatty Acids, Edward O'Brien

LSU Master's Theses

Tall oil is a byproduct of the standard wood pulping process in the paper industry. It is primarily made up of C:18 fatty acids, rosin acids and a minor fraction of neutrals. Normally, tall oil is further distilled into fractions and then hydrogenated or dehydrogenated into different products. In this project, three heterogeneous catalytic methods of producing byproducts of various distilled tall oil fractions were examined at lower temperatures and pressures than the industry norm in an attempt to develop cheaper production processes. Reactions were conducted in stirred batch reactors of different sizes and product compositions were analyzed primarily by …


Application Of Satellite Remote Sensing Imagery To Bridge Scour Evaluation, Xiaoyan Zhao Jan 2011

Application Of Satellite Remote Sensing Imagery To Bridge Scour Evaluation, Xiaoyan Zhao

LSU Master's Theses

The overall goal of this research is to evaluate the applicability of the existing HEC-18 method to Louisiana bridges that are mostly situated on cohesive soils and hence to develop a more reliable design method for scour depth and scour rate prediction. Pier research in sandy soils and cohesive soils shows that the sandy soils are known to erode particle by particle, while cohesive soils usually erode in clumps rather than individual particles, which is caused by from the different bonding mechanisms between sandy soils and cohesive soils. Because the bonding in cohesive soils is so complex, the prediction of …


Foldable Substrates For Micro-Ultrasonic Transducers, Karthik Balasubramanian Jan 2011

Foldable Substrates For Micro-Ultrasonic Transducers, Karthik Balasubramanian

LSU Master's Theses

Ultrasound has broad range of applications from underwater examination, nondestructive testing of materials and medical diagnosis and treatment. The ultrasonic transducer plays an vital role in determining the resolution, sensitivity, as well as other diagnostic capabilities of an ultrasonic imaging system. Current piezoelectric transducer which dominates the medical field has limited applications compared to the capacitive ultrasonic transducer. The capacitive transducer is easy to fabricate compared to the piezoelectric transducer. In this work, the fabrication of a foldable substrate for a capacitive ultrasonic transducer has been discussed. The foldable substrate was fabricated using an ultrathin silicon wafer which is 50 …


Implementing Lean In Healthcare Warehouse Operations - Evaluation Of 5s Best Practice, Sanjith Venkateswaran Jan 2011

Implementing Lean In Healthcare Warehouse Operations - Evaluation Of 5s Best Practice, Sanjith Venkateswaran

LSU Master's Theses

Lean strategies in healthcare aim at improving patient throughput, reducing medication errors, redesigning work flow, improving patient safety, and reducing cycle time. Documented studies to improve healthcare’s warehouse operation are not common in the literature. Managing types of medical supplies has always been a priority due to demand uncertainties and the risk of shortages that would profoundly affect patient safety. This study showcases two implementation approaches for the Lean tool 5S (Hybrid and Traditional) conducted in three different hospitals’ central warehouses at Ochsner Health System. These warehouses store similar medical products with over 1000 types of supplies (e.g. syringes, gloves, …


Assymmetry In Distribution Systems: Causes, Harmful Effects And Remedies, Isaac Plummer Jan 2011

Assymmetry In Distribution Systems: Causes, Harmful Effects And Remedies, Isaac Plummer

LSU Master's Theses

ABSTRACT: Current and voltage asymmetry denigrates the power system performance. The current asymmetry reduces efficiency, productivity and profits at the generation, transmission and distribution of electric energy. Voltage asymmetry reduces efficiency, productivity and profits at the consumption/utilization level. There are a lot of conference and journal papers on the subject of voltage and current asymmetry, however, the information is scattered over a large number of journals and conferences and published over several years. Therefore, the thesis provides a comprehensive compilation of all possible published information on current and voltage asymmetry in the electrical power systems. Published information on sources of …


Experimental Study Of Cognitive Radio Test-Bed Using Usrp, Venkat Vinod Patcha Jan 2011

Experimental Study Of Cognitive Radio Test-Bed Using Usrp, Venkat Vinod Patcha

LSU Master's Theses

Cognitive Radio is an emerging technology that enables efficient utilization of the spectrum. As such, it has created great interests in industrial and research fields. Many people have proposed test-bed models for the performance analysis of primary and secondary users in a real-time noise environment. However, these test-beds are generally lacking in their range of capabilities as well as accurate implementation of the proposed models. In this thesis, we develop our test-bed on USRP to achieve the spectrum sensing and co-existence of primary and secondary users, while implementing the rendezvous protocols for secondary traffic coordination. We first demonstrate the spectrum …


Supercritical Pyrolysis Of Toluene, Khue Dang Nguyen Jan 2011

Supercritical Pyrolysis Of Toluene, Khue Dang Nguyen

LSU Master's Theses

The development of future high-speed aircrafts will required the jet fuel to act as the primary engine coolant to absorb excess heat produced by the engine components. To aid in removing the excess heat and reducing the aircraft’s weight, future jet fuels used for high-speed aircrafts will act as both coolant and fuel; however, by exposing the fuels to temperatures and pressures above their critical point, they undergo pyrolysis to form larger and/or more abundant polycyclic aromatic hydrocarbons (PAH) and eventually carbonaceous solid deposits in the pre-combustion environment. The formation of solid deposits in the pre-combustion environment results in clogging …


Integrating Demand And Traffic Simulation Modeling To Evaluate Adaptive Evacuation Plans, Thomas Jude Montz, Jr. Jan 2011

Integrating Demand And Traffic Simulation Modeling To Evaluate Adaptive Evacuation Plans, Thomas Jude Montz, Jr.

LSU Master's Theses

Significant efforts are currently being made by transportation officials to improve the planning and preparation of mass evacuations. The idea of adaptive evacuation plans is an avenue of research that could help improve future evacuation processes. Adaptive evacuation plans stem from the observation that different disaster threat scenarios require different evacuation responses. While adaptive evacuation planning can be generalized to any form of evacuation planning, this project focused on adaptive planning in the context of a hurricane evacuation.

This project was the first to adapt the demand models of Fu, et al, and Cheng, et al, into a regional-scale traffic …


Performance Of Twin-Rotor Dc Homopolar Motor, Zhiwei Wang Jan 2011

Performance Of Twin-Rotor Dc Homopolar Motor, Zhiwei Wang

LSU Master's Theses

A new concept of dual-rotor motor with counter-rotating propeller increases the efficiency of the ship propulsion used in marine industry. This concept can be realized by twin-rotor permanent magnet homopolar disc motor, which is the object of this thesis. The objectives of this thesis are to determine the motor electromechanical parameters applying a 3-D FEM modeling and to analyze the motor performance in steady-state and dynamic conditions. The objectives of this thesis are to determinate the PM DC homopolar twin-rotor disc motor electromechanical parameters by 3-D FEM modeling. Furthermore, the PM DC Homopolar perform determination in steady-state and dynamic conditions. …


Pool Boiling Enhancement Via Micro Ratchets, Lance Austin Brumfield Jan 2011

Pool Boiling Enhancement Via Micro Ratchets, Lance Austin Brumfield

LSU Master's Theses

Nucleate boiling is an attractive method for achieving high heat flux at low superheat temperatures. It is frequently used for industrial applications such as heat exchangers and is being considered to cool advanced central processing units (CPU) which produce heat fluxes on the order of 1 MW/m2 and are becoming increasing less efficient to cool via forced conduction of air. The issues with implementing nucleate boiling as a cooling mechanism lies in the difficulty of quantifying the complex and numerous mechanisms which control the process. A comprehensive nucleate boiling model has yet to be formulated and will required in order …


Evaluation Of Simultaneous Water And Gas Injection Using Co2, Shrinidhi Shetty Jan 2011

Evaluation Of Simultaneous Water And Gas Injection Using Co2, Shrinidhi Shetty

LSU Master's Theses

Miscible CO2 injection is the second largest contributor to global enhanced oil recovery, as it has successfully undergone extensive laboratory tests and field applications for recovering residual oil left behind after waterflooding. Prolific incremental recoveries have been obtained for some fields. Although miscible CO2 injections generally have excellent microscopic displacement efficiency they often result in poor sweep efficiency. In order to address sweep problems and maximize recoveries, other schemes of gas injection have been developed. Two such processes are water-alternating-gas (WAG) and simultaneous water-and-gas (SWAG) injection. WAG and SWAG have been successfully used to minimize poor sweep. Improved gas utilization …


Two-Dimensional Numerical Modeling Of A Proposed Freshwater Diversion From The Bonnet Carre Spillway To The Labranche Wetlands, Josef Patrick Hoffmann Jan 2011

Two-Dimensional Numerical Modeling Of A Proposed Freshwater Diversion From The Bonnet Carre Spillway To The Labranche Wetlands, Josef Patrick Hoffmann

LSU Master's Theses

Engineered modifications to the lower Mississippi River within the past century have limited the magnitude and frequency of flood events in wetlands along the Louisiana coast. Without this natural delivery of freshwater, sediment, and nutrients, the ecological health of these wetlands are now degrading. A recent study within the Bonnet Carre Spillway has revealed that the 7,623 acres of floodway between the Mississippi River and Lake Pontchartrain is one of the few areas in Louisiana that is actively accreting land as a result of pulsed sediment-laden freshwater input during high discharge events in the Mississippi River. On the other hand, …


Developing A Tool To Characterize The Ultradian Rhythm In Diploid Saccharomyces Cervisiae Using The Reporter Gene Green Fluorescent Protein, Imran Chiragh Jan 2011

Developing A Tool To Characterize The Ultradian Rhythm In Diploid Saccharomyces Cervisiae Using The Reporter Gene Green Fluorescent Protein, Imran Chiragh

LSU Master's Theses

Biological rhythms control many temporal behaviors of organism, such as the sleep cycle, hearts rhythms, seasonal animal migrations etc. Understanding these rhythms would provide insight into the temporal process of living organisms. Saccharomyces cerevisiae, a budding yeast, is an ideal model organism to study biological rhythms in eukaryotic cells because of its sequenced genome and discerned processes. By characterizing the biological rhythm in budding yeast, insight can be gained into more complex organisms. Previous studies have exhibited oscillatory behavior of oxygen consumption and determined that deletion of the GTS1 gene dissipates this rhythm. However, to further understand the specific behavior …


Pavement Structural Evaluation Using The Rolling Wheel Deflectometer, Ahmed Moustafa Abdel-Khalek Jan 2011

Pavement Structural Evaluation Using The Rolling Wheel Deflectometer, Ahmed Moustafa Abdel-Khalek

LSU Master's Theses

The Rolling Wheel Deflectometer (RWD) offers the benefit to measure pavement deflection without causing any traffic interruption or compromising safety along the tested road segments. This study describes a detailed field evaluation of the RWD system in Louisiana in which 16 different test sites representing a wide array of pavement conditions were tested. Measurements were used to assess the repeatability of RWD measurements, to examine the effect of truck speeds, and to study the relationship between RWD and FWD deflection measurements and pavement conditions. Based on the results of the experimental program, it was determined that the repeatability of RWD …


The Transient Wave Effect And Real Losses Correlation-Frequency, Temporal, And Spatial Analysis, Dina Sa Knight Jan 2011

The Transient Wave Effect And Real Losses Correlation-Frequency, Temporal, And Spatial Analysis, Dina Sa Knight

LSU Master's Theses

Water distribution systems are prone to transients since pumps need to be started and stopped, pumps may have sudden flow changes, human blunders can occur, equipment may fail, or other unavoidable natural events may ensue. Surge modeling techniques are available to calculate variations in pressure, under extreme or normal operating conditions, serving as a tool to predict extreme events in order to design a suitable system and, or, to aid in the implementation of proper measures to mitigate transients. However, modeling an entire water network system may not be cost effective and may require extensive research and time especially in …


Fragility Analysis Of Building Envelope Components Subject To Windborne Debris Impact Hazard, Alexander Henry Herbin Jan 2011

Fragility Analysis Of Building Envelope Components Subject To Windborne Debris Impact Hazard, Alexander Henry Herbin

LSU Master's Theses

This thesis presents a methodology for developing windborne debris (WBD) impact fragility curves for building envelope components (BECs) by using stochastic finite element (FE) models. These fragility curves provide the probabilistic description of the impact resistance of BECs subject to an impact event described by an appropriate intensity measure (IM). Accurate fragility curves are essential in the development of a general probabilistic performance-based engineering framework for mitigation of WBD impact hazard. Monte Carlo simulation is used in combination with the FE method to propagate uncertainties in the BEC’s model parameters and WBD impact location. As an application example, the fragility …


Design, Development, And Testing Of A Multi-Agent Autonomous Surface Fleet For Environmental Applications, Daniel Davis Smith Jan 2011

Design, Development, And Testing Of A Multi-Agent Autonomous Surface Fleet For Environmental Applications, Daniel Davis Smith

LSU Master's Theses

As costs have decreased and both computational complexity and robustness have increased, the use of autonomous vehicles in real-world environments has increased dramatically. The development of a fleet of autonomous surface vehicles able to coordinate their actions through communications provides a significant tool for numerous water-based applications such as the reduction of predatory birds on aquaculture ponds, tracking of pollutant gradients, and water quality mapping applications. A fleet of three autonomous surface vehicles (ASVs) was developed using the best characteristics from earlier designs. Each vehicle is a dual-pontoon, dual-paddlewheel design powered by batteries recharged using a vehicle-mounted solar array that …


Electrochemical Reduction Of Co2 To Methanol, Minh Tuyen Hoang Le Jan 2011

Electrochemical Reduction Of Co2 To Methanol, Minh Tuyen Hoang Le

LSU Master's Theses

An efficient method to convert CO2 to fuels using renewable energy could displace crude oil without increasing CO2 emission and provide high-density energy storage reservoirs similar to liquid fuels or batteries. Although photoelectrochemical conversion of CO2 is possible, solar-to-fuel efficiencies are lower than the combination of conventional photovoltaics (up to 40% efficiency) and electrochemical cells (up to 80% Faradaic efficiency). In the electrochemical case, electrical energy from renewable sources may be converted to hydrocarbons or alcohols using electrocatalysts. The direct reduction of CO2 to CH3OH is known to occur at several types of electrocatalysts including oxidized Cu electrodes. In this …


Modeling Of First-Flush Reactor For Stormwater Treatment, Shaowei Sun Jan 2011

Modeling Of First-Flush Reactor For Stormwater Treatment, Shaowei Sun

LSU Master's Theses

Stormwater runoff is one of the most common sources of non-point source water pollution to lakes, rivers and estuaries. Nitrate-nitrogen in stormwater runoff is an important limiting factor to the eutrophication phenomenon. While most pollutants and nutrients, including nitrate-nitrogen, in stormwater are discharged into receiving waters during the first-flush period, no existing Best Management Practices (BMPs) are specifically designed to capture and treat the first-flush portion of urban stormwater runoff. In addition, nitrate-nitrogen removal rates of most existing BMPs are relatively low. This thesis presents results from both laboratory experiments and numerical modeling of nitrate-nitrogen removal in a designed first-flush …


A Study Of A Smog-Fog-Smog Cycle And The Processing Of Pah And Oxy-Pah By A Fog Cloud, Kalindi Pramod Khadapkar Jan 2011

A Study Of A Smog-Fog-Smog Cycle And The Processing Of Pah And Oxy-Pah By A Fog Cloud, Kalindi Pramod Khadapkar

LSU Master's Theses

Fog is a multiphase dynamic system which can provide a setting for various physicochemical processes affecting the fate of various organic pollutants such as polycyclic aromatic hydrocarbons (PAH) and their oxygenated forms (oxy-PAH) in the atmosphere. This study focuses on the processing of PAH and oxy-PAH during a smog-fog-smog cycle. Two field campaigns were carried out during the winters of year 2010 and year 2011 in the Central Valley of California, sampling two fog events in Fresno and five fog events in Davis. To study the transformations and distributions of PAH and oxy-PAH, different atmospheric species (fog water, gas phase, …