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The Effect Of Elbow Position And Grip Span On Isometric Grip Strength And Force Distribution Of Fingers., Xuewei (Sue). Chen
The Effect Of Elbow Position And Grip Span On Isometric Grip Strength And Force Distribution Of Fingers., Xuewei (Sue). Chen
Electronic Theses and Dissertations
Injuries to the hand, lower arm, and shoulder are often attributed to inappropriate use or poor design of hand tools. Isometric grip, performed with the angled handles of pliers was investigated in this study. For this thesis, three factors were studied. They were grip type (traditional and reversed grip), elbow position (0$\sp\circ$, 30$\sp\circ$, 60$\sp\circ$, 90$\sp\circ$, and 120$\sp\circ$), and grip span (50, 60, and 70 mm). The resultant forces between the jaws of the pliers and finger forces were measured under each condition. The purpose of this study was to evaluate the effect of elbow position and grip span on grip …
Hydraulic Study Of Secondary Stilling Basins., Taban. Sowlati Hashjani
Hydraulic Study Of Secondary Stilling Basins., Taban. Sowlati Hashjani
Electronic Theses and Dissertations
In dams with low tailwater levels, the hydraulic jump may not occur on the protected apron. This could result in a severe local scour on the downstream river bed which could endanger the safety of the dam. A traditional solution is to place crushed rock in the scour hole to prevent further scour; however, this method is not a permanent solution. The focus of this research is to investigate the effect, on the scour profile, of installing a secondary stilling basin downstream of the primary basin. This results in a dual stilling basin. The primary stilling basin is the original …
Improving The Performance Of Soil-Metal Structures Subjected To Loss Of Soil Support., Karlos Ernesto. Melgar
Improving The Performance Of Soil-Metal Structures Subjected To Loss Of Soil Support., Karlos Ernesto. Melgar
Electronic Theses and Dissertations
Years of dependable service and a multitude of wide ranging installations have led to the corrugated steel pipe industry to play a major role in modern engineering technology. Flexible steel conduits play an important role in the form of culverts, storm sewers, subdrains, spillways, underpasses, conveyor conduits and service tunnels; for highways, railways, airports, municipalities, recreation areas, industrial parks, flood and conservation projects, water pollution abatement and many other programs. In recent years developments have been made which allow engineers and contractors the use of conventional corrugated structural plates to design and build structures having larger spans and increased permissible …
A Skew Third Order Upwinding Scheme For Modelling Settling Tanks., Hany Zarif Amin. Gerges
A Skew Third Order Upwinding Scheme For Modelling Settling Tanks., Hany Zarif Amin. Gerges
Electronic Theses and Dissertations
A new high accuracy numerical technique has been developed. This technique is based on a Skew Third Order Upwinding Scheme (STOUS) which eliminates numerical diffusion. This scheme introduces cross-difference terms to overcome the instability problems of the component-wise one-dimensional formulas for simulating multi-dimensional flows. Small physically unrealistic overshooting and undershooting have been avoided by using a well established technique known as the Universal Limiter. STOUS is also compared with another third order upwinding technique which is referred to as Uniformly Third Order Interpolation Algorithm (UTOPIA). A complete von Neumann stability analysis is conducted on both schemes to show the stability …
Compressive Strength Of Steel Single Angles Loaded Through Two-Bolts In One Leg., Raymond. Haidar
Compressive Strength Of Steel Single Angles Loaded Through Two-Bolts In One Leg., Raymond. Haidar
Electronic Theses and Dissertations
One hundred and ninety seven steel single angles loaded through two bolts in one leg were tested for their compressive strengths. They included five different sizes (76 x 51 x 6.4, 127 x 76 x 6.4, 64 x 64 x 6.4, 64 x 64 x 4.8, and 76 x 76 x 6.4 mm) and slenderness ratios varying from 69 to 201. The gauge distances were varied from the minimum to the maximum possible value for each size of angle. The effect of the connection type (snug tight and pretensioned) was also investigated. The effect of the width of the connected …
Surface Finish Enhancement In A Turning Operation Via Control Of The Depth Of Cut., Evangelos. Liasi
Surface Finish Enhancement In A Turning Operation Via Control Of The Depth Of Cut., Evangelos. Liasi
Electronic Theses and Dissertations
During the past two decades there has been a steady increase in the number of computer numerically controlled (CNC) machine tools. Such problems as dimensional accuracy and surface finish are recently receiving widespread attention. This theoretical investigation explores the possibility of decreasing the surface roughness by suppressing radial tool-workpiece relative displacements via control of the depth of cut. In order to achieve this goal various control strategies are developed and evaluated via simulation. An integrated model of the turning process in the most flexible component which manifests itself in the surface roughness, i.e., the radial direction was generated from an …
Effect Of Be On The Nucleation And Growth Of Beta' Phase In Aluminum-Magnesium-Silicon Alloy., Ali. Hatab
Effect Of Be On The Nucleation And Growth Of Beta' Phase In Aluminum-Magnesium-Silicon Alloy., Ali. Hatab
Electronic Theses and Dissertations
An investigation on the effect of Be on $\beta\sp\prime$ phase precipitation in Al-0.7%Mg-0.4%Si alloy was carried out using microhardness and resistivity measurements, and optical and TEM observations. It is shown that addition of 0.4%Be to an Al-0.7%Mg-0.4%Si (base) alloy significantly enhances the age hardening response and increases the peak hardness levels of the alloy, which is associated with a refinement of the $\rm\beta\sp\prime(Mg\sb2Si)$ precipitate. Hardness and resistivity techniques used to study the precipitation kinetics show that the two methods are in good agreement for monitoring the transformation rates. A kinetic analysis shows that A precipitation of $\beta\sp\prime$ phase in both …
Effects Of Acoustic Pressure Pulses On Wall Wetting In An Intake Port., Robert B. Haramic
Effects Of Acoustic Pressure Pulses On Wall Wetting In An Intake Port., Robert B. Haramic
Electronic Theses and Dissertations
This study was undertaken to determine whether pressure pulses that propagate through the induction system of a port injected engine influence wall wetting occurring on the surfaces of the intake port. Water was used as the working fluid to eliminate the need for a special room and measures otherwise required to deal with fire hazards that would be present if gasoline were used. An extensive experimental apparatus was constructed that would permit the control of air flow, fuel pressure, throttle position and acoustic pressure pulse amplitude while allowing measurements to be made of wall wetting that occurs in the intake …
Parameterizing And Capturing Diagnostics Information During Design., Roozbeh. Rahimpour
Parameterizing And Capturing Diagnostics Information During Design., Roozbeh. Rahimpour
Electronic Theses and Dissertations
This thesis presents a new methodology for constructing a device's computer model to be used as the knowledge-base component of the model-based diagnostics expert system of the device. It is shown that parameterized functional and behavioural knowledge of a device could be applied to the diagnostics action to pin point the root cause of a fault. Four underlying concepts which are examined and deployed in this thesis to support the proposed methodology are: Parametric and feature based design, object oriented methodology for analysis and design, manufacturing as incorporating useful information into material, and using functional knowledge in diagnosing faults. The …
A Model Of Operation Allocation With Lot Splitting In Flexible Assembly Systems., Fazlullah. Sharief
A Model Of Operation Allocation With Lot Splitting In Flexible Assembly Systems., Fazlullah. Sharief
Electronic Theses and Dissertations
In this thesis, the loading problem in Flexible Assembly Systems (FASs) has been studied. Two integer programming models of the loading problem are presented. The first model is an extension of an earlier 0/1 integer programming model which takes into consideration the unit transportation costs. The total cost in model 1 thus is a summation of assembly costs and unit transportation costs. An operation in a FAS may be performed at more than one station. However, this capacity is not fully explored and taken advantage of if the complete production requirements of an assembly are sent to one station only …
Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly
Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly
LSU Historical Dissertations and Theses
An advanced prototype computer-assisted deep water drilling well control system was developed using process control technology. The goal of the system was to improve rig safety by reducing the potential for surface and underground blowouts through providing enhanced bottom hole and casing seat pressure control during the well kill process. The system developed is capable of full computer control of the fluid pump and drilling choke control functions during normal well control operations. The system provides computer-assistance in collecting and curve fitting slow circulation rate pump pressure data, in developing a well kill program (kill sheet), and in detecting anomalies …
Feasibility Study On The Reduction Of Hydrostatic Pressure In A Deep-Water Riser Using A Gas-Lift Method., Clovis Antonio Lopes
Feasibility Study On The Reduction Of Hydrostatic Pressure In A Deep-Water Riser Using A Gas-Lift Method., Clovis Antonio Lopes
LSU Historical Dissertations and Theses
Recent successful exploration efforts in deep waters have heightened interest in developing oil and gas reservoirs on the continental slope. Leases have been obtained in water depths up to 10,000 ft with a requirement that they be drilled within the next decade. Use of current techniques to drill these leases will require extremely large floating drilling units and large diameter marine riser systems. This study presents the results of a feasibility study on the use of an automated gas-lift system for a marine riser that will maintain the hydrostatic pressure in the subsea well-head equal to that of the sea …
Cellulose-Reinforced Composites And Srim And Rtm Modeling., Mohammad Fahrurrozi
Cellulose-Reinforced Composites And Srim And Rtm Modeling., Mohammad Fahrurrozi
LSU Historical Dissertations and Theses
Structural reaction injection molding (SRIM) cellulosic/polyurethane composites were prepared from various forms of cellulosic mats, and elastomeric polyurea-urethane (PUU) and rigid polyurethane (PU) formulations. Mats (woven and non-woven) prepared from different sources of fibers with lignin content ranging from zero (cotton) to at least 10% (sugar cane and kenaf fibers) performed comparably in PUU/cellulosic composites. Young's modulus and tensile strength of PUU/cellulosic composites were doubled with 5% and 7% fiber loading respectively. Young's modulus and tensile strength of PU/cellulosic composites were improved by 300% and 30%, respectively, with 7% fiber loading, whereas their bending moduli and strengths were improved up …
Optimization And Scale-Up Of Thiarubrine A Production From Hairy Root Cultures Of Ambrosia Artemisiifolia., Santosh G. Bhagwath
Optimization And Scale-Up Of Thiarubrine A Production From Hairy Root Cultures Of Ambrosia Artemisiifolia., Santosh G. Bhagwath
LSU Historical Dissertations and Theses
Thiarubrine A (TA), a plant secondary metabolite synthesized by members of the family Asteraceae possesses antifungal and antiviral properties and is a potential pharmaceutical. The objective of the work was the optimization and scale-up of a bioprocess for the production of TA using hairy root cultures of Ambrosia artemisiifolia. At the inception of the work an established hairy root culture of the model system was used as inoculum in reactor experiments for the development of a protocol for the quantification of TA and in subsequent shake flask experiments to determine optimum culture conditions. TA accumulation closely paralleled growth and then …
Coupled Field Equations For Saturated Soils And Its Application To Piezocone Penetration And Shield Tunneling., Murad Yusuf Abu-Farsakh
Coupled Field Equations For Saturated Soils And Its Application To Piezocone Penetration And Shield Tunneling., Murad Yusuf Abu-Farsakh
LSU Historical Dissertations and Theses
An elasto-plastic coupled system of equations are formulated here in order to describe the time-dependent deformation of saturated cohesive soils. Formulation of these equations is based on the principle of virtual work and the theory of mixtures for inelastic porous media as proposed by Prevost (1980) and Kiousis and Voyiadjis (1988). The saturated soil is considered as a mixture consisting of two deformable media, the solid grains and the water. Each medium is regarded as a continuum and follows its own motion. The coupled equations are developed for large deformations with finite strains in an updated Lagrangian reference frame. The …
Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos
Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos
LSU Historical Dissertations and Theses
We apply stochastic techniques towards the solution of the two-dimensional Laplace's equation in boundary value problems encountered in the calculation of electrostatic potentials in electron lenses and deflectors. The justification of these techniques arises from an astonishingly simple but far-reaching principle, which has been known for a long time but has been rarely used: the potential at any point in the interior of a charge-free region can be calculated by performing random walks starting at this point and terminating at the boundary of the region--the potential is then the average of the potential boundary values (assumed known) over the random …
Chemical Vapor Deposition Of Copper Films., Narendra Shamkant Borgharkar
Chemical Vapor Deposition Of Copper Films., Narendra Shamkant Borgharkar
LSU Historical Dissertations and Theses
We have studied the kinetics of copper chemical vapor deposition (CVD) for interconnect metallization using hydrogen (H$\sb2$) reduction of the Cu(hfac)$\sb2$ (copper(II) hexafluoroacetylacetonate) precursor. Steady-state deposition rates were measured using a hot-wall microbalance reactor. For base case conditions of 2 Torr Cu(hfac)$\sb2$, 40 Torr H$\sb2$, and 300$\sp\circ$C, a growth rate of 0.5 mg cm$\sp{-2}$ hr$\sp{-1}$ (ca. 10 nm min$\sp{-1}$) is observed. Reaction order experiments suggest that the deposition rate passes through a maximum at partial pressure of 2 Torr of Cu(hfac)$\sb2$. The deposition rate has an overall half-order dependence on H$\sb2$ partial pressure. A Langmuir-Hinshelwood rate expression is used to …
Feature-Based Models For Three-Dimensional Data Fitting., Gregory Todd Dobson
Feature-Based Models For Three-Dimensional Data Fitting., Gregory Todd Dobson
LSU Historical Dissertations and Theses
There are numerous techniques available for fitting a surface to any supplied data set. The feature-based modeling technique takes advantage of the known, geometric shape of the data by deforming a model having this generic shape to approximate the data. The model is constructed as a rational B-spline surface with characteristic features superimposed on its definition. The first step in the fitting process is to align the model with a data set using the center of mass, principal axes and/or landmarks. Using this initial orientation, the position, rotation and scale parameters are optimized using a Newton-type optimization of a least …
Numerical Simulation Of Geosynthetic Reinforced Earth Structures Using Finite Element Method., Surajit Pal
Numerical Simulation Of Geosynthetic Reinforced Earth Structures Using Finite Element Method., Surajit Pal
LSU Historical Dissertations and Theses
Geosynthetics are widely used as reinforcements in various earth structures. Current design methods are based on some simplified assumptions and are primarily modified versions of limit equilibrium methods used in design of the unreinforced earth structures. All of these design methods are conservative and result in uneconomical design. The best method for verifying the design assumptions and studying the stress-deformation behavior of geosynthetic reinforced earth structures is by constructing a series of large scale test walls with adequate instrumentation and collecting data from them. But the cost involved in such a scheme precludes undertaking this kind of study. Thus Numerical …
Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero
Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero
LSU Historical Dissertations and Theses
A new interpretation method that allows for the determination of the fluid type present in a formation of interest was developed. The new method is referred to as the "Three Neutron Porosity Log". The method is based on an algorithm that determines three apparent neutron porosities. These porosities, derived from the raw counts of the dual-spaced neutron tool, have three different radii of investigation. All three neutron porosities, near, far, and ratio, when properly calibrated read the true porosity in water-bearing zones. In oil or gas-bearing zones the mud filtrate invasion profile will cause the three apparent neutron porosities to …
Injection Of Species Under Electrical Field To Enhance Bioremediation., Fazle Rabbi
Injection Of Species Under Electrical Field To Enhance Bioremediation., Fazle Rabbi
LSU Historical Dissertations and Theses
Electrokinetics is one of the most viable alternatives for injecting/extracting water, organic and ionic species in low permeability soils as well as heterogeneous media because the transport processes are independent of the pore sizes. A better understanding of the principles offers the opportunity to employ multi-component species transport under electrical fields to inject electron acceptors, nutrients and other process additives for enhancement of in-situ bioremediation in low permeability and heterogeneous media. This study assesses the potential to employ and exploit the principles of multi-component species transport under electrical fields as mean to supplement, enhance and engineer in-situ bioremediation. It was …
Evaluation Of Alternative Gases For Immiscible Cyclic Injection., Sara Shayegi
Evaluation Of Alternative Gases For Immiscible Cyclic Injection., Sara Shayegi
LSU Historical Dissertations and Theses
Cyclic gas injection processes have been primarily restricted to the use of pure CO$\sb2$ or CO$\sb2$ that has been slightly contaminated with reservoir gases. However, it is difficult to employ CO$\sb2$ in certain circumstances due to transport, economic, or corrosion problems. This study presents the results of laboratory investigations of the cyclic gas injection process using methane, nitrogen and combinations of these gases with CO$\sb2$. Cyclic gas injections were performed at immiscible conditions in consolidated sandstone cores that contained waterflood residual oil under analogous conditions to previous cyclic CO$\sb2$ injections for comparative purposes. Pure methane recovered approximately the same amount …
Linear Matrix Inequality Approach To Robust Emergency Lateral Control Of A Highway Vehicle With Time-Varying Uncertainties., Robert Edward Benton Jr
Linear Matrix Inequality Approach To Robust Emergency Lateral Control Of A Highway Vehicle With Time-Varying Uncertainties., Robert Edward Benton Jr
LSU Historical Dissertations and Theses
New linear-matrix-inequality (LMI) based methods are developed for the static-output-feedback stabilization and reduced-gain static-output-feedback stabilization of time-invariant systems. Unlike previous methods, the static-output-feedback method is non-iterative in LMI solutions. The methods are extended to design robust static-output-feedback controllers for time-varying systems using a polytopic-systems approach. Examples are given which demonstrate the use of each of the new methods. The specific problem of emergency lateral control of a highway vehicle is then addressed using the new robust static-output-feedback method. A controller is designed which robustly stabilizes the vehicle over the range of highway speeds (15 to 30 m/s) and a range …
Development Of Thin Gold Film Thermal Sensors For Synchrotron X-Ray Exposure Diagnostics., Harish M. Manohara
Development Of Thin Gold Film Thermal Sensors For Synchrotron X-Ray Exposure Diagnostics., Harish M. Manohara
LSU Historical Dissertations and Theses
High aspect ratio lithography utilizes high intensity exposure sources, such as synchrotron storage rings, to deposit sufficient dose in the resist to produce a successful pattern transfer. Such highly powerful sources are known to cause undesirable thermal effects in the mask-resist-substrate system. Hence, the measurement of temperature of a mask-resist-substrate system during irradiation is an important exposure diagnostic feature. Deposition of a reasonably accurate dose in the resist is controlled by knowledge of the exposure source intensity. Periodic monitoring of the synchrotron radiation beam power and its spatial distribution at the exposure plane is necessary. In this research, diagnostic techniques …
Wood Fiber Reinforced Polypropylene Composites., Minqiu Lu
Wood Fiber Reinforced Polypropylene Composites., Minqiu Lu
LSU Historical Dissertations and Theses
Mechanical properties of polypropylene (PP)/wood fiber composites depend not only on the properties of each primary component but also on a complex interaction of several factors such as fiber loading and size, characteristics of fiber-polymer matrix interface, and the processing conditions. Both sequential and simultaneous composites are formulated in this research. First, sequential composites are made by compounding wood fibers with PP in the presence of maleated polypropylene (MPP) as a coupling agent in a twin-screw extruder. A small amount of MPP (1 wt%) present in these sequential composites can increase the tensile strength of the composites significantly. The tensile …
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
LSU Historical Dissertations and Theses
The mechanism of fish protein solubilization by acid hydrolysis at elevated temperatures was investigated. Rate expressions for the solubilization were determined using pilot scale data with two different rate determination methods. A postulated mechanism was verified and estimated rates were evaluated on five independent verification experiments. A functional relationship between nonprotein byproduct concentration and whiteness of fish protein hydrolysate (FPH) was developed. Initial and set-point operating variables were calculated to produce FPH with acceptable color characteristics for food use. A batch reactor was used for duplicate hydrolysis trials conducted at three acid and three temperature levels for four hours. Samples …
Cost Analysis And Air Pollution Impact Of Electric Vehicles On A Metropolitan Area., Hector David Arias-Varela
Cost Analysis And Air Pollution Impact Of Electric Vehicles On A Metropolitan Area., Hector David Arias-Varela
LSU Historical Dissertations and Theses
During the 1990's, increasing attention has been paid to electric vehicles (EV's) because of their potential to reduce air pollution in metropolitan areas such as the Los Angeles Metropolitan Area in the U.S., Mexico City and Its Metropolitan Area in Mexico, Greater London in the United Kingdom and other urban areas. However, few studies to determine the costs and benefits of reducing air pollution by introducing EV's into these mega cities have been carried out. A model to determine the marginal costs and environmental impact of electric vehicles on a metropolitan area is designed in this study. The model simulates …
A Micro-Mechanical Fatigue Damage Model For Uni-Directional Metal Matrix Composites., Rainer Echle
A Micro-Mechanical Fatigue Damage Model For Uni-Directional Metal Matrix Composites., Rainer Echle
LSU Historical Dissertations and Theses
A micro-mechanical damage model for high cycle fatigue loading based on thermo-dynamical principles is developed for uni-directional continuous fiber reinforced metal matrix composites. The model uses a micro-mechanical based theory to predict the fatigue damage evolution in the individual constituents of the composite material, namely the fibers and the matrix, from which the overall fatigue damage evolution in the composite is obtained. The micro-mechanical analysis is performed for each individual constituent using stress and strain concentration tensors based on the Mori-Tanaka method. A fatigue damage criterion based on thermo-dynamical principles is developed and applied to each of the constituents. Fatigue …
Development Of An Analysis System For Discontinuities In Rigid Airfield Pavements., Michael Ivan Hammons
Development Of An Analysis System For Discontinuities In Rigid Airfield Pavements., Michael Ivan Hammons
LSU Historical Dissertations and Theses
The response of the rigid pavement slab-joint-base structural system is complex, and accurately predicting the response of such a system requires a significant degree of analytical sophistication. The research reported in this dissertation has defined some essential features required to adequately model the system and has demonstrated a technique to develop a comprehensive three-dimensional (3D) finite element model of the rigid pavement slab-joint-foundation structural system. Analysis of experimental data from the 1950s confirms that explicit modeling of dowels is not required to model the structural response of the system. Additional experimental data gathered as a part of this research indicates …
An Object-Oriented Fuzzy Expert System For The Design Of Rotating Operations., Xin. Yuan
An Object-Oriented Fuzzy Expert System For The Design Of Rotating Operations., Xin. Yuan
Electronic Theses and Dissertations
In the thesis, a prototype object-oriented fuzzy expert system called SAM (Smart Assistant to Machinist) is presented for rotating cutter selection and cutting condition design. Object-Oriented Design and Programming Methods are employed to construct and implement the system. Based on partial and imprecise information, the system is able to select rotating cutter products available in current commercial market, and design cutting conditions for an optimized objective. The system consists of four modules: a database, a rule base, a cutter selection module and a cutting condition design module. The database consists of six kinds of data files: machinability of workpieces, machining …