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Assessment Of Shearing Phenomenon And Porosity Of Porous Media Using Microfocus Computed Tomography, Bashar Adeeb Alramahi Jan 2004

Assessment Of Shearing Phenomenon And Porosity Of Porous Media Using Microfocus Computed Tomography, Bashar Adeeb Alramahi

LSU Master's Theses

Microfocus x-ray computed tomography (μCT) is a powerful non-destructive scanning technique to study the internal fabric of granular materials. In this thesis, μCT was applied to two cases. The first case involves studying the behavior of particles in a triaxial specimen during shearing. Three-dimensional translation and rotation of the particles were tracked throughout the shearing process, and they were used to calculate the local strain distributions. Moreover, the local dilatancy angle distribution was calculated throughout experiment. These distributions were compared to study the changes in the behavior of the particles at different stages of the test. It was noticed that …


Development Of A Neural Network Approach For The Assessment Of The Performance Of Traffic Sign Retroreflectivity, Nagajyothi Swargam Jan 2004

Development Of A Neural Network Approach For The Assessment Of The Performance Of Traffic Sign Retroreflectivity, Nagajyothi Swargam

LSU Master's Theses

The goal of the research was to develop a new predictive tool for assessing the performance of traffic sign retroreflectivity and to compare the developed tool with the existing linear regression models. Retroreflectivity decreases as sign sheeting ages. Currently Louisiana Department of Transportation and Development (LADOTD) replace signs with low reflectivity based on driver complaints. This practice might have resulted in premature sign replacement (removal of signs with several years of in-service life still remaining) or in non-replacement of signs that are not in compliance with LADOTD minimum reflectivity standards. In this study, both neural network models and regression models …


Stabilization Of Flue Gas Desulfurization Sludge For Application In Marine Environments, Tej Kour Jan 2004

Stabilization Of Flue Gas Desulfurization Sludge For Application In Marine Environments, Tej Kour

LSU Master's Theses

Flue Gas Desulfurization sludge (FGD, CaSO4·2H2O, CaSO3·1/2H2O) is a waste by-product produced when sorbent slurry is passed through wet scrubbers. FGD contains higher concentrations of Ca, S, Si, Fe, Al and Br making it of great environmental concern. Presently only 16% of 24 million metric tons (MT) of FGD sludge produced is being recycled; the rest is disposed in landfills. This research was focused towards stabilizing FGD sludge with Portland Type II cement and Class C fly ash to produce lightweight fill material to be used in the construction of coastal devices. The specific objectives included the development of a …


Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner Jan 2004

Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner

LSU Master's Theses

The use of high-speed data acquisition systems, inexpensive and reliable transducers, and better models of interpretation have combined to make elastic wave tomographic imaging of geotechnical engineering systems easier to accomplish both in the laboratory and in the field. An important application of these developments is that the evaluation of states of effective stress in soils using images of elastic wave velocity distribution. As a consequence, it is possible to experimentally estimate the state of induced and in-situ effective stresses and to compare these results with established models of stress distribution based on the theory of elasticity (e.g., Boussinesq’s solution). …


Experimental And Computational Modeling Of Granular Materials, Orlando Boscan Jan 2004

Experimental And Computational Modeling Of Granular Materials, Orlando Boscan

LSU Master's Theses

4-inch cubical sand specimens were been tested under drained conditions using a wide range of stress paths. The testing was performed by means of a true (cubical) triaxial device that has been conditioned for this study. This testing set-up consisted of a servo-controlled, single-boundary type apparatus, with six flexible membranes that create a center cavity surrounding the soil specimens. This thesis illustrates the functioning of the triaxial device, including detailed descriptions of the device components, sample preparation, and a practical application related to the mechanical characterization of granular materials using critical state soil mechanics. An experimental program, based on the …


Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua Jan 2004

Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua

Electronic Theses and Dissertations

In this thesis, the parallel barrier analysis feature in the Federal Highway Administration Traffic Noise Model (FHWA TNM), which is based on RAYVERB was used to explore the effects of multiple reflections due to single and parallel barriers and the use of absorptive treatment. Database was developed from the data collected from previous research efforts was used to generate a best fit equation model that can be used as a predetermining tool to determine the magnitude of parallel barrier insertion loss. The best fit equation model was then used to test against measured/model result and TNM prediction results for its …


Optimal Design Of Pump And Treat Remediation Systems : Treatment Modeling, Source Modeling And Time As A Decision Variable, Karen L. Endres Jan 2004

Optimal Design Of Pump And Treat Remediation Systems : Treatment Modeling, Source Modeling And Time As A Decision Variable, Karen L. Endres

Dissertations, Master's Theses and Master's Reports - Open

Groundwater optimization and simulation is a maturing science. Research work contained in this thesis extends into areas that have not been fully explored. The incorporation of source and treatment systems selection and design produces information to help decision makers. Further insight is gained by evaluating some of the requirements and standards enforced by regulations such as, remediation time.

The technical aspects of a remediation system are set by the physical properties and the regulatory constraints enforced. As an example, the addition of a realistic treatment system gives more accurate cost estimates, but the pump and treat (PAT) systems parameters do …


Multi-Objective Conjunctive Use Optimization, H. C. Fayad, Richard C. Peralta Jan 2004

Multi-Objective Conjunctive Use Optimization, H. C. Fayad, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This paper presents a simulation/optimization model based on artificial neural networks and genetic algorithms for solving multi-objective conjunctive water use problems. The model simulates and optimizes water flows in a hydraulically connected reservoir-stream-aquifer system. It is a powerful tool to help water managers and authorities in developing conjunctive water management strategies and evaluating tradeoffs between conflicting goals.


Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad Jan 2004

Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad

Civil and Environmental Engineering Faculty Publications

Planners must sometimes decide how to restrict or reduce groundwater use to prevent unacceptable future problems. Often there are several alternatives (policies). Comparing policies can involve formulating a sustained groundwater yield optimization problem and computing an optimal groundwater pumping strategy for each. This is easy via the SOMOS simulation/optimization (S/O) model. Subsequent analysis can include: flow simulation to predict transient water level response to pumping; and economic evaluation to estimate costs and returns. Two examples predict the best consequences of potential physical and legal management policies for alluvial and valley basin fill aquifers hydraulically linked to surface waters. Results show …


Material Length Scales In Gradient-Dependent Plasticity/Damage And Size Effects: Theory And Computation, Rashid Kamel Abu Al-Rub Jan 2004

Material Length Scales In Gradient-Dependent Plasticity/Damage And Size Effects: Theory And Computation, Rashid Kamel Abu Al-Rub

LSU Doctoral Dissertations

Structural materials display a strong size-dependence when deformed non-uniformly into the inelastic range: smaller is stronger. This effect has important implications for an increasing number of applications in structural failure, electronics, functional coatings, composites, micro-electro-mechanical systems (MEMS), nanostructured materials, micro/nanometer fabrication technologies, etc. The mechanical behavior of these applications cannot be characterized by classical (local) continuum theories because they incorporate no ‘material length scales’ and consequently predict no size effects. On the other hand, it is still not possible to perform quantum and atomistic simulations on realistic time and structures. It is therefore necessary to develop a scale-dependent continuum theory …


Dynamic Performance Of Bridges And Vehicles Under Strong Wind, Suren Chen Jan 2004

Dynamic Performance Of Bridges And Vehicles Under Strong Wind, Suren Chen

LSU Doctoral Dissertations

The record of span length for flexible bridges has been broken with the development of modern materials and construction techniques. With the increase of bridge span, the dynamic response of the bridge becomes more significant under external wind action and traffic loads. The present research targets specifically on dynamic performance of bridges as well as the transportation under strong wind. The dissertation studied the coupled vibration features of bridges under strong wind. The current research proposed the modal coupling assessment technique for bridges. A closed-form spectral solution and a practical methodology are provided to predict coupled multimode vibration without actually …


Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu Jan 2004

Development Of Dynamic Travel Demand Models For Hurricane Evacuation, Haoqiang Fu

LSU Doctoral Dissertations

Little attention has been given to estimating dynamic travel demand in transportation planning in the past. However, when factors influencing travel are changing significantly over time – such as with an approaching hurricane - dynamic demand and the resulting variation in traffic flow on the network become important. In this study, dynamic travel demand models for hurricane evacuation were developed with two methodologies: survival analysis and sequential choice model. Using survival analysis, the time before evacuation from a pending hurricane is modeled with those that do not evacuate considered as censored observations. A Cox proportional hazards regression model with time-dependent …


Numerical Modeling Of Strain Localization In Granular Materials Using Cosserat Theory Enhanced With Microfabric Properties, Mustafa Alsaleh Jan 2004

Numerical Modeling Of Strain Localization In Granular Materials Using Cosserat Theory Enhanced With Microfabric Properties, Mustafa Alsaleh

LSU Doctoral Dissertations

Finite element solution in the updated Lagrangian frame is used to investigate the strain localization phenomenon "shear bands" in granular materials. The micro-polar theory was used as the mathematical foundation for the continuum formulations. A laboratory testing results are used for verification and comparison with the numerical simulation. Silica sand and glass beads with different shape indices, size and surface roughness were tested under biaxial and triaxial loading conditions to investigate the physics of the problem. The shape non-uniformity and the irregular surface roughness of the grains were studied carefully to evaluate their effect on shear band characteristics. To this …


Modeling Event-Based Coupled Hydrologic And Mass Transport In Small Urban Watersheds, Yuhong Sheng Jan 2004

Modeling Event-Based Coupled Hydrologic And Mass Transport In Small Urban Watersheds, Yuhong Sheng

LSU Doctoral Dissertations

To investigate the event-based coupled hydrologic and mass transport processes of particulate matter and their eventual fate in unit operations/processes, several methodologies were developed. Discrete rainfall-runoff events data were collected at two similar urban watersheds for model calibration and verification. A mathematically and physically-based criterion was proposed to differentiate rainfall-runoff events between either mass-limited or flow-limited. Statistical techniques of Logistic Regression and Discriminant Analysis were utilized to derive classification rules for event categories based on hydrologic data only. With watersheds assumed as either lumped systems or distributed systems, physically-based semi-empirical models were developed to simulate particulate mass delivery process during …


Comprehensive Evaluation Of Animated Instructional Software For Mechanics Of Materials, Timothy A. Philpot, Richard H. Hall Jan 2004

Comprehensive Evaluation Of Animated Instructional Software For Mechanics Of Materials, Timothy A. Philpot, Richard H. Hall

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During the past three years, the Basic Engineering Department at the University of Missouri--Rolla has been developing a second-generation suite of instructional software called MecMovies for the mechanics of materials course. In the Fall 2003 semester, MecMovies was integrated into assignments throughout the entire semester for one of the six UMR mechanics of materials sections. This paper presents a comparison of student performance in the experimental section with student performance in five control sections along with discussion of student qualitative ratings and comments.


Methodology For The Development Of A Highway Asset Management System For Indiana, Zongzhi Li, Kumares C. Sinha Jan 2004

Methodology For The Development Of A Highway Asset Management System For Indiana, Zongzhi Li, Kumares C. Sinha

JTRP Technical Reports

Highway asset management is a systematic process that aims to preserve, expand, and operate highway assets in the most cost-effective manner. It is an analytical tool that facilitates organized, logical, and integrated decision-making in asset management practice. This study proposes a methodology for the development of a highway asset management system that addresses asset valuation, performance modeling, marginal benefit analysis, and multicriteria decision-making, including tradeoff analysis as well as project selection and programming. While most existing management systems deal with individual physical highway assets or system usage only under certainty or risk, this research focuses on the management of an …


Safety Of Intersections On High-Speed Road Segments With Superelevation, Peter T. Savolainen, Andrzej P. Tarko Jan 2004

Safety Of Intersections On High-Speed Road Segments With Superelevation, Peter T. Savolainen, Andrzej P. Tarko

JTRP Technical Reports

In recent years, the State of Indiana has built a number of intersections where one or both of the roads are located on curves. The AASHTO Policy on Geometric Design of Highways and Streets recommends that in such cases “the alignment should be as straight and the gradient as flat as practical.” This wording, consistent with Part V of the Indiana Design Manual, allows for the design of intersections on curves if other solutions prove to be too expensive. Several of these intersections have raised safety concerns and led to expensive corrective measures. Due to these safety and economic issues, …


Configuration Of Traffic-Responsive Plan Selection System Parameters And Thresholds: Robust Bayesian Approach, Montasir M. Abbas, Anuj Sharma Jan 2004

Configuration Of Traffic-Responsive Plan Selection System Parameters And Thresholds: Robust Bayesian Approach, Montasir M. Abbas, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

Traffic-responsive plan selection (TRPS) is one of the two major closed-loop system modes of operation. The TRPS mode is more beneficial than its competitor (time-of-day mode) because of its ability to accommodate abnormal traffic conditions such as incidents, special events, and holiday traffic. However, no guidelines are available for optimal setup of TRPS systems. Improper configuration of a TRPS system can result in inefficient system performance or unstable operation in which the closed-loop system operates in a perpetual transitioning state. The TRPS mechanism implemented in current traffic signal controllers is described, and a Bayesian-based methodology for selecting an optimal set …


Flexural Strengthening Of Bridge Piers Using Frp Composites, Tarek Alkhrdaji, Antonio Nanni Jan 2004

Flexural Strengthening Of Bridge Piers Using Frp Composites, Tarek Alkhrdaji, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of FRP jackets for increasing the shear capacity and the flexural ductility of reinforced concrete (RC) columns was demonstrated in many studies. However, for smaller axial loads, the contribution of FRP jackets to flexural strength is minimal. using FRP sheets in the direction of a column with end anchorage to improve its flexural capacity at the base is not easily achieved. This paper reports on a research project aimed at upgrading the flexural capacity of RC piers using near-surface mounted (NSM) FRP rods. Flexural strengthening and testing to failure of the piers were carried out on a bridge …


Accuracy And Interferences For Enzyme-Linked Immunoassay Tests For Atrazine, Craig D. Adams, Hua Jiang, Michael Mcguire, Nicole Graziano, Alan Roberson, Michelle Frey Jan 2004

Accuracy And Interferences For Enzyme-Linked Immunoassay Tests For Atrazine, Craig D. Adams, Hua Jiang, Michael Mcguire, Nicole Graziano, Alan Roberson, Michelle Frey

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Atrazine is one of the most commonly used herbicides in the United States, therefore it is a regulatory concern and is extensively monitored in the environment, especially in drinking water. Because of the higher costs of gas chromatography (GC) methods, utility managers and regulators are considering the increased use of enzyme-linked immunosorbent assay (ELISA) methods for monitoring atrazine. an ELISA test kit was recently approved by the US Environmental Protection Agency. the research in this article points out potential biases and inaccuracies that may occur with such test kits. ELISA test kits for atrazine are typically precise (repeatable) but often …


Hydrologic Variations Within Created And Natural Wetlands In Southeastern Virginia, Aaron Dyer Despres Jan 2004

Hydrologic Variations Within Created And Natural Wetlands In Southeastern Virginia, Aaron Dyer Despres

OES Theses and Dissertations

The hydrology of wetlands, particularly how wetland soils collect, store, and redistribute water strongly affects how wetland systems function. In created wetlands, construction processes and materials influence the hydrology and consequently, the potential for successful reestablishment of target vegetation communities. During 2002–2004, the Virginia Department of Transportation constructed large mitigation wetlands on two different Quaternary aged surfaces with very similar hydrogeomorphic conditions. The Sandy Bottom Nature Park site (SBNP) located in Hampton, VA and rests on the sandy loam Tabb Formation while the Charles City Wetland site (CCW) lies on the older and clay-rich Shirley Formation. This study documents and …


A Novel Approach To Determine The Astronomical Vessel Position, Chih-Li Chen, Tien-Pen Hsu, Jiang-Ren Chang Dec 2003

A Novel Approach To Determine The Astronomical Vessel Position, Chih-Li Chen, Tien-Pen Hsu, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

In this paper, a novel approach based on the trigonometric equation solving technique is developed to solve the classical problem of celestial navigation. It is shown that this approach, namely, the simultaneous equal-altitude equations method (SEEM), can directly calculate the astronomical vessel position (AVP) without an additional graphical procedure. It is also found that the SEEM is not only simpler than the matrix method but is also more straightforward as compared with the spherical triangle method. In addition, aimed at the drawbacks of the intercept method, an improved approach with the new computation procedure is presented to plot the celestial …


The Selection Of Materials For Roller Chains From The Perspective Of Manufacturing Process, Rahmat Saptono Dec 2003

The Selection Of Materials For Roller Chains From The Perspective Of Manufacturing Process, Rahmat Saptono

Makara Journal of Technology

The selection of materials for an engineering component is not only requested by its design function and shape, but also the sequence through which it is manufactured. The manufacturing operation of roller chains involves drawing and trimming processes aimed at producing semi-finished chain drives component with a well-standardized dimension. In addition to final combination of properties required by design constraints, the ability of materials to be formed into a desired shape and geometry without failure is also critical. The objective of materials selection should therefore involve additional attributes that are not typically accommodated by the standard procedure of materials selection. …


Application Of Tabu Search Algorithm In Job Shop Scheduling, Betrianis Betrianis, Putu Teguh Aryawan Dec 2003

Application Of Tabu Search Algorithm In Job Shop Scheduling, Betrianis Betrianis, Putu Teguh Aryawan

Makara Journal of Technology

Application of Tabu Search Algorithm in Job Shop Scheduling. Tabu Search is one of local search methods which is used to solve the combinatorial optimization problem. This method aimed is to make the searching process of the best solution in a complex combinatorial optimization problem(np hard), ex : job shop scheduling problem, became more effective, in a less computational time but with no guarantee to optimum solution.In this paper, tabu search is used to solve the job shop scheduling problem consists of 3 (three) cases, which is ordering package of September, October and November with objective of minimizing makespan (Cmax). …


Identification Of The First Limiting Amino Acid In Cooked Polished White Rice Fed To Weanling Holtzman Rats, Mellova Masrizal, J. B. Lamb Dec 2003

Identification Of The First Limiting Amino Acid In Cooked Polished White Rice Fed To Weanling Holtzman Rats, Mellova Masrizal, J. B. Lamb

Makara Journal of Technology

Forty-eight male weanling rats (91 g) were utilized to study the nutritional adequacy of cooked polished white rice. Rats were individually housed, and allowed ad libitum access to one of six treatment diets. Treatment diets were 1) polished white rice plus 10% casein and 0.18% methionine, CAS, 2) polished white rice, WHR, 3) polished white rice plus 0.45% lysine, LYS, 4) polished white rice plus0.40% methionine, MET, 5) polished white rice plus 0.30% threonine, THR, 6) polished white rice plus 0.45% lysine, 0.40% methionine, and 0.40% threonine, COM. Rice was cooked prior diet formulation using a 3 to 1 ratio …


Trust, Collaboration, And Financial Return In Conservation/Development Partnerships, New England Environmental Finance Center Dec 2003

Trust, Collaboration, And Financial Return In Conservation/Development Partnerships, New England Environmental Finance Center

Economics and Finance

In early 2002 the New England Environmental Finance Center hosted a series of roundtable discussions among municipal officials, residential developers, land trust representatives, and others about "Innovative Approaches to Land Conservation and Smart Growth". Among our observations was that for many of the over 20 conservation/development partnerships we discussed in the series, creation and maintenance of trust was central to success or failure of various stages of the partnership. This suggested a link between creation of trust and financial return for traditionally opposed project partners.

To further examine this matter, we interviewed 11 round table participants and asked questions about …


Innovative Contracting Prequalification/Selection Model Using Analytical Hierarchy Process (Ahp), Saad J. Zidan Dec 2003

Innovative Contracting Prequalification/Selection Model Using Analytical Hierarchy Process (Ahp), Saad J. Zidan

Masters Theses

Design-Build, Cost-Plus-Time, and warranty are the three innovative contracting methods that the Federal Highway Administration (FHWA) decided to fund. FHWA allowed the usage of these methods in federally funded projects if this will result in reducing time, improving quality, and saving tax payers' money. Prequalification is recognized as the best way of assuring that contractors do have the required qualifications to deliver projects successfully. Prequalification is even more critical when low-bid selection method is used with any of the innovative contracting, since incompetent contractors may get awarded for low-bids that are not based on valid assumptions.

This study presents a …


Color Management Of Desktop Input Devices: Quantitative Analysis Of Profile Quality, Xiaoying Rong Dec 2003

Color Management Of Desktop Input Devices: Quantitative Analysis Of Profile Quality, Xiaoying Rong

Masters Theses

This thesis investigates the color management principle and input device profiling. The input devices discussed in this thesis are flatbed scanners.

In this thesis, the human visual system, CIE L*a*b* color space, ICC profiles are reviewed, and the evaluation of profile quality is discussed. Grayscale and standard color targets of three primary suppliers are used to create profiles for a scanner. The quantitative analyses of the quality of different profiles, created by two primary commercial profiling software, are conducted according to the Delta-E of the CIE L*a*b* color space. Finally, the relationship of different color targets and profiles for desktop …


Slides: Encana, John Moran Nov 2003

Slides: Encana, John Moran

Workshop on Directional Drilling in the Rocky Mountain Region (November 13)

Presenter: John Moran, Reservoir Engineer, Encana Oil & Gas

23 slides

Abstract: For companies doing directional drilling, what are the direct and indirect costs and benefits? When is it economical and what factors does industry take into account in making the decision to utilize directional drilling?


Notes From The Directional Drilling Workshop, University Of Colorado Boulder. Natural Resources Law Center Nov 2003

Notes From The Directional Drilling Workshop, University Of Colorado Boulder. Natural Resources Law Center

Workshop on Directional Drilling in the Rocky Mountain Region (November 13)

20 pages

"These notes were taken by one of our law students attending the workshop. They are not a verbatim transcript and they were not supplied by, and may not have been reviewed by, the speakers. There may be errors or gaps in the notes and for these we apologize in advance. Where the speaker provided an abstract of their talk, these are included and noted as such."