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Engineered Struvite Precipitation: Impacts Of Component-Ion Molar Ratios And Ph, Jun Wang, Joel Gerard Burken, Xiaoqi Zhang, Rao Y. Surampalli Jan 2005

Engineered Struvite Precipitation: Impacts Of Component-Ion Molar Ratios And Ph, Jun Wang, Joel Gerard Burken, Xiaoqi Zhang, Rao Y. Surampalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Struvite precipitation has the potential for removing and recovering phosphorus from agricultural wastewater streams, such as concentrated animal feeding operations wastewater. However, impacts of anticipated component-ion molar ratios and potentially interfering ions are unknown as are the compounding pH relationship with respect to all potential complexes. This research experimentally investigates and mathematically models these factors. Emphasis is placed upon the composition of formed deposits and model validation with experimental data. Results show that calcium is a major interfering ion affecting the deposit composition, decreasing struvite purity. X-ray diffraction (XRD) and scanning electron microscopy + energy dispersive spectrometry were used to …


Emergency Earthquake Routes; Part I, Criteria For Selection Of Primary Routes; And Part Ii: Route Seismic Vulnerability Aspects, Julio Ramirez, Srinivas Peeta, Mete Sozen, Luis Garcia, Kannan Viswanath Jan 2005

Emergency Earthquake Routes; Part I, Criteria For Selection Of Primary Routes; And Part Ii: Route Seismic Vulnerability Aspects, Julio Ramirez, Srinivas Peeta, Mete Sozen, Luis Garcia, Kannan Viswanath

JTRP Technical Reports

The occurrence of a strong earthquake in Indiana or neighboring states, as has occurred in the past, has serious implications for the State Transportation System with respect to adequate response. The definition of Earthquake Emergency Routes for the State of Indiana became a priority for the Indiana Department of Transportation. These Emergency Routes take into account various aspects related to transportation including coverage of population and area and travel time along these routes, and issues related to structural and geotechnical seismic vulnerability of the roads and bridges along these routes. Part I of the overall study report formulates a multi-commodity …


Family Of Compaction Curves For Chemically Modified Soils, Radha Krishna Daita, Vincent P. Drnevich, Daehyeon Kim Jan 2005

Family Of Compaction Curves For Chemically Modified Soils, Radha Krishna Daita, Vincent P. Drnevich, Daehyeon Kim

JTRP Technical Reports

Lime and Lime Kiln Dust (LKD) are widely used for modifying/stabilizing pavement subgrades. The addition of lime or LKD involves chemical processes that are dependent on many parameters. For natural subgrades, quality control is based on moisture and unit weight requirements using manual interpolations of one-point test data on a family of curves. For modified soils, moisture and unit weight measurements are insufficient for quality control and other tests must be considered. Various possible quality control methods for LKD-modified subgrades were evaluated. This research produced an Excel-based program to automate the generation of a family of curves and one-point data …


Its Strategies For Minimization Of Fine Particulates, Ahmed S. Soliman, Robert Bertram Jacko, Barry K. Partridge Jan 2005

Its Strategies For Minimization Of Fine Particulates, Ahmed S. Soliman, Robert Bertram Jacko, Barry K. Partridge

JTRP Technical Reports

The purpose of the study was to quantify the impact of traffic conditions such as free flow and congestion on local air quality. The Borman Expressway in Northwest Indiana is considered a test-bed for this research due to the high volume of class-9-truck traffic traveling on it, as well as the existing and continuing installation of the Intelligent Transportation System (ITS) to improve the traffic management along the highway stretch. An empirical Traffic-Air-Quality model (TAQ model) was developed to estimate the PM2.5 emission factors (g/mi) based solely on the measured traffic parameters such as average speed, average acceleration and truck …


Bs News Jan 2005

Bs News

Building Services Engineering

No abstract provided.


Two Dimensional Sediment Transport Model Using Parallel Computers, Vikas Singh Jan 2005

Two Dimensional Sediment Transport Model Using Parallel Computers, Vikas Singh

LSU Master's Theses

Management and development of water bodies is vital for meeting domestic, agricultural, energy and industrial needs. To that end, dams, artificial channels, lakes and other water structures have been constructed. Management and development of these structures encounter problems of land erosion, reservoir silting, and degradation and aggradation of channel beds, which need to be addressed. Fundamental to these problems are sediment transport, erosion and deposition. Numerical modeling of sediment transport is the best tool to simulate sediment transport in a water body. This study develops a vertically integrated two-dimensional numerical sediment transport model. Sediment transport is simulated in two parts …


Water Quality Modeling For Unconventional Bod, Trieu Van Le Jan 2005

Water Quality Modeling For Unconventional Bod, Trieu Van Le

LSU Master's Theses

Predictions of the dissolved oxygen (DO) concentration in a stream are sensitive to the choice of Biochemical Oxygen Demand (BOD) reaction model which frequently is assumed to be first order, although published BOD data sets from analyses of samples from rivers show that many are described best by second order or three-halves order BOD reaction. Two DO models for a stream are developed, one with a second order and the other with a three-halves order BOD reaction. The DO equations are solved using Laplace transform method which simplifies the mathematical solution of the model equations by avoiding difficult to evaluate …


Damage Mechanics Of Composite Materials Using Fabric Tensors, Ziad N. Taqieddin Jan 2005

Damage Mechanics Of Composite Materials Using Fabric Tensors, Ziad N. Taqieddin

LSU Master's Theses

The major objective of this work is to relate continuum damage mechanics introduced through the concept of fabric tensors to composite materials within the framework of classical elasticity theory. A model of directional data-damage mechanics for composite materials is formulated using fabric tensors. In addition, a general hypothesis for damage mechanics is postulated. It is seen that the two available hypotheses of elastic strain equivalence and elastic energy equivalence may be obtained as special cases of the postulated general hypothesis. This general hypothesis is then used to derive the sought relationship between the damage tensor for composite materials and the …


Modeling The Fate And Transport Of Chlorinated Benzenes In Baton Rouge Bayou, Sudheer Nimmagadda Jan 2005

Modeling The Fate And Transport Of Chlorinated Benzenes In Baton Rouge Bayou, Sudheer Nimmagadda

LSU Master's Theses

Knowledge of the fate and transport of chlorinated benzenes is necessary at certain sites for effective remediation of contaminated soils using plants. Current research is examining the capability of wetland plants to catalyze degradation or attenuate migration, but again requires knowledge of the uptake of contaminants from an aqueous environment. A two stage model was used to estimate the rate of uptake of contaminants from sediments. The first stage of the model predicts pollutant leaching rates from sediments to the overlying water, which would then be fed into the plant or bioreactor model systems. In this study the flux from …


Sediment Tmdl Calculations For Amite River, Pradeep Kumar Mishra Jan 2005

Sediment Tmdl Calculations For Amite River, Pradeep Kumar Mishra

LSU Master's Theses

The Amite River is recognized as one of the 15 water bodies impaired by sediments in Louisiana. A sediment TMDL calculation for the Amite River is required by the EPA. Based on EPA’s Protocol sediment TMDL calculations for the Upper Amite River are conducted in this thesis. The sediment TMDL calculations are composed of four parts: (1) Development of a new sediment transport and dispersion model for the Amite River, (2) Estimation of sediment loads (sources) produced by watershed erosion, (3) Flow computation, and (4) Determination of sediment TMDL for the Amite River. Using the mass conservation principle and Reynolds …


Modeling Destination Choice And Measuring The Transferability Of Hurricane Evacuation Patterns, Naveen Kumar Modali Jan 2005

Modeling Destination Choice And Measuring The Transferability Of Hurricane Evacuation Patterns, Naveen Kumar Modali

LSU Master's Theses

In this study a gravity model was used to model destination choice during a hurricane evacuation. Hurricane Floyd data was used to calibrate and apply the gravity model. Two different models were generated for different destination types; home of friends/relative and hotels and motels are the two different destination types for which the models were generated. The performance of the gravity model was tested by comparing the observed and estimated OD matrices using the chi-squared test. The results have indicated that gravity model developed in this study can successfully reproduce the observed trip destinations during a hurricane evacuation The Floyd …


Experimental Quantification And Dem Simulation Of Micro-Macro Behaviors Of Granular Materials Using X-Ray Tomography Imaging, Yanrong Fu Jan 2005

Experimental Quantification And Dem Simulation Of Micro-Macro Behaviors Of Granular Materials Using X-Ray Tomography Imaging, Yanrong Fu

LSU Doctoral Dissertations

A non-invasive experimental method and a clustering DEM model were developed in this study to investigate micro-macro behaviors of real granular materials with irregular particle shape configurations. The investigated behaviors include global deformations, failure strengths and residual strengths, stress and strain distributions, local coordination number, local void ratio, particle kinematics, and fabric orientation distributions. The experimental method includes an approach to automatically identify and recognize multiple particles using x-ray computed tomography imaging (XCT) and an enhanced approach to digitally represent microstructures of granular materials. The digitally represented microstructure can be directly employed for numerical simulation setup. A compression test and …


Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman Jan 2005

Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman

LSU Doctoral Dissertations

This study developed a coregionalized model to estimate hydraulic conductivity using spatial cross correlation between hydraulic conductivity and borehole geophysical data (a transform of the formation factor). An experimental pseudocross variogram is used instead of a cross variogram because data are not collocated. Experimental variogram uncertainty is investigated using confidence intervals for the experimental variogram calculated assuming variogram sills are lognormally distributed. These intervals are used for sensitivity modeling using kriging, cokriging, simulation and cosimulation. The hydraulic conductivity fields generated by kriging, cokriging, simulation, and cosimulation are then used in a high-resolution groundwater model created using telescopic mesh refinement (TMR) …


Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke Jan 2005

Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke

LSU Doctoral Dissertations

Shells and plates are very important for various engineering applications. Analysis and design of these structures is therefore continuously of interest to the scientific and engineering community. Accurate and conservative assessments of the maximum load carried by the structure, as well as the equilibrium path in both elastic and inelastic range are of paramount importance. Elastic behaviour of shells has been very closely investigated, mostly by means of the finite element method. Inelastic analysis on the other hand, especially accounting for damage effects, has received much less attention from the researchers. A computational model for finite element, elasto-plastic and damage …


Physically Based Multiscale-Viscoplastic Model For Metals And Steel Alloys: Theory And Computation, Farid H. Abed Jan 2005

Physically Based Multiscale-Viscoplastic Model For Metals And Steel Alloys: Theory And Computation, Farid H. Abed

LSU Doctoral Dissertations

The main requirement of large deformation problems such as high-speed machining, impact, and various primarily metal forming, is to develop constitutive relations which are widely applicable and capable of accounting for complex paths of deformation. Achieving such desirable goals for material like metals and steel alloys involves a comprehensive study of their microstructures and experimental observations under different loading conditions. In general, metal structures display a strong rate- and temperature-dependence when deformed non-uniformly into the inelastic range. This effect has important implications for an increasing number of applications in structural and engineering mechanics. The mechanical behavior of these applications cannot …


Evaluation Of Artificial Intelligence Based Models For Chemical Biodegradability Prediction, James R. Baker, Dragan Gamberger, James R. Mihelcic, Aleksandar Sabljic Dec 2004

Evaluation Of Artificial Intelligence Based Models For Chemical Biodegradability Prediction, James R. Baker, Dragan Gamberger, James R. Mihelcic, Aleksandar Sabljic

Michigan Tech Publications, Part 1

This study presents a review of biodegradability modeling efforts including a detailed assessment of two models developed using an artificial intelligence based methodology. Validation results for these models using an independent, quality reviewed database, demonstrate that the models perform well when compared to another commonly used biodegradability model, against the same data. The ability of models induced by an artificial intelligence methodology to accommodate complex interactions in detailed systems, and the demonstrated reliability of the approach evaluated by this study, indicate that the methodology may have application in broadening the scope of biodegradability models. Given adequate data for biodegradability of …


Assessment Of The Accuracy Of Approximate Methods In The Analysis Of Plane Frame Structures, I Rubaratuka Dec 2004

Assessment Of The Accuracy Of Approximate Methods In The Analysis Of Plane Frame Structures, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

pproximaic methods of analysis are widely used in the analysis OJ' frames for preliminary design due to their simplicily as compared to exact analysis meth o ds Ough they a re nol as accurate. In this paper. the methods Of hinges and portal frame are described and have been used to analyze a statically indeterminate frame by taking inro account the bending stiffness of the frame members. The obtained results are comparable Io the magnitudes of forces determined by exact methods Of analysis.


The Effects Of Influent Debit On Hydrodynamic Characteristic Of Bojongsoang Facultative Pond: Without Wind Effects, Rositayanti Hadisoebroto, Suprihanto Notodarmojo Dec 2004

The Effects Of Influent Debit On Hydrodynamic Characteristic Of Bojongsoang Facultative Pond: Without Wind Effects, Rositayanti Hadisoebroto, Suprihanto Notodarmojo

Makara Journal of Technology

The Effects of Influent Debit on Hydrodynamic Characteristic of Bojongsoang Facultative Pond: Without Wind Effects. The performance of facultative pond in Bojongsoang WWTP have reported to be unstable. One of the cause of the unstable performance is the hydrodynamic characteristics that not met the criterion. The improper hydrodynamic characteristics are included the existence of dead-zone, the short-circuiting, and the turbulence due to eddy current. The study was to analyze the effect of the influent debit variation on the hydrodynamic characteristics of the pond using mathematical model. The two-dimensional hydrodynamic model was built from two hydrodynamic equations which are continuity and …


Algoritmo Genético Para Calibração Automática De Um Simulador De Tráfego Em Rodovias De Pista Simples, C. Y. Egami, J. R. Setti, Laurence Rilett Dec 2004

Algoritmo Genético Para Calibração Automática De Um Simulador De Tráfego Em Rodovias De Pista Simples, C. Y. Egami, J. R. Setti, Laurence Rilett

Department of Civil and Environmental Engineering: Faculty Publications

Este trabalho relata o desenvolvimento de um sistema automático para calibração do modelo de simulação de tráfego em rodovias de pista simples TRARR, baseado em um algoritmo genético. O processo de calibração consiste em procurar valores para alguns parâmetros selecionados do simulador, de tal modo que a diferença entre as correntes de tráfego simuladas e as observadas em campo sejam minimizadas. Os parâmetros escolhidos para a calibração estão relacionados principalmente ao comportamento dos motoristas e, por isso, de difícil calibração. As diferenças entre a simulação e o fluxo real foram determinadas em termos de duas medidas de desempenho: a velocidade …


Efficient Algorithm For Computing Einstein Integrals, Junke Guo, Pierre Y. Julien Dec 2004

Efficient Algorithm For Computing Einstein Integrals, Junke Guo, Pierre Y. Julien

Department of Civil and Environmental Engineering: Faculty Publications

Analytical approximations to Einstein integrals are proposed. The approximations represented by two fast-converging series are valid for all values of their arguments. Accordingly, the algorithm can be easily incorporated into professional software like HEC-RAS or HEC-6 with minimum computational effort.


Multiobjective Optimization Of Seismic Structures, Franklin Y. Cheng, Dan Li, Jeffrey Ger Dec 2004

Multiobjective Optimization Of Seismic Structures, Franklin Y. Cheng, Dan Li, Jeffrey Ger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a constrained Mult objective optimization method in the form of a robust, practical, problem-independent formulation based on genetic algorithm combined with game theory and investigates the effect of Mult objective optimization on structural design. the study includes objectives, constraints, and design variables as well as their effect on structural design and behavior. the algorithm comprises - Mult objective fitness function, niche method, and Pareto set filter. a 10-story setback building is used to illustrate the evaluation of three choices: steel frame, reinforced concrete frame, composite steel and reinforced concrete frame. Evaluation is based on economics as well …


The Effectiveness Of Computer-Based Tutorials In Learning Computer-Aided Design Methods For Tool Design Procedures, Andrew Moroni Hall Nov 2004

The Effectiveness Of Computer-Based Tutorials In Learning Computer-Aided Design Methods For Tool Design Procedures, Andrew Moroni Hall

Theses and Dissertations

Throughout the past twenty-five years the process of designing and manufacturing a product has been revolutionized by the integration of Computer Aided Design (CAD). Although three-dimensional solid modeling, or 3-D CAD offers a better representation of the product in a virtual environment, it can be complicated and difficult to learn. Tutorials have been developed to assist manufacturing tool design student in the learning of 3-D CAD principles as they apply to tool design. This study seeks to test the effectiveness of those tutorials. A BYU tool design class was divided into two groups according to their assigned laboratory time. The …


Web Crippling Of Cold Formed Steel Multi -Web Deck Sections Subjected To End One-Flange Loading, J. A. Wallace, R. M. Schuster Nov 2004

Web Crippling Of Cold Formed Steel Multi -Web Deck Sections Subjected To End One-Flange Loading, J. A. Wallace, R. M. Schuster

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Presented in this paper are the results of a study where the web crippling capacity of multi-web deck sections subjected to End One-Flange loading (EOF) was investigated. A total of 148 tests were completed. New coefficients were established using the data from this study and any appropriate data from previous work. New resistance factors and factors of safety were also established. Also investigated in this study was the web crippling capacity of partially fastened deck sections and re-entrant deck type sections subjected to EOF loading. Seventy-seven (77) partially fastened multi-web decks and 36 re-entrant decks were tested in this study. …


Introduction To The Theory And Finite Element Implementation Of (Steel) Plasticity, Herm Hofmeyer Nov 2004

Introduction To The Theory And Finite Element Implementation Of (Steel) Plasticity, Herm Hofmeyer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper tries to enlighten the subject of (numerical) plasticity by presenting fundamental theory and some very practical examples. For a two-dimensional plain stress state, a Hubert-Henky yield criterion is derived. The flow rule is discussed, including an explanatory numerical example. The yield criteria and flow rule are theoretically applied in a four node finite element. This element is used to show some of the conditions and limitations of a plastic calculation in the finite element method. Finally, a real finite element calculation is made for illustrating the theory derived.


Improved Signal Integrity In Ieee 1149.1 Boundary Scan Designs, Efren De Jesus Rangel Taboada Nov 2004

Improved Signal Integrity In Ieee 1149.1 Boundary Scan Designs, Efren De Jesus Rangel Taboada

Theses and Dissertations

This work is an analysis of solutions to problems derived from inherent timing and signal integrity issues in the use and application of the IEEE 1149.1 Standard at the board level in conjunction with its test system. Setup or hold times violations may occur in a boundary scan chain using IEEE 1149.1 compliant devices. A practical study of the TDI-TDO scan data path has been conducted to show where problems may arise in relationship to a particular board topology and test system. This work points to differences between passing and failing scan path tests for problem characterization. Serial data flow …


Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju Oct 2004

Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju

Business and Information Technology Faculty Research & Creative Works

Students from Ten Schools, Representing Seven Countries, Used Interactive Multimedia as a Part of their Engineering Statics Classes. the Software Consisted of Four Modules, Which Focused On: Mohr's Circle; Centroid and Moment of Inertia; Stress Transformation; and Structural Analysis. the Students Completed On-Line Surveys About their Experience with the Software. Analysis of the Results Indicated that Students Rated their Knowledge of the Subject Matter Covered in the Software as Increasing Significantly as a Consequence of using the Software. However, This Increase Was Substantially More Pronounced for Students in U.S. Schools. Students Rated the Software as Significantly More Effective Than their …


Inspection And Deterioration Of Bridge Decks Constructed Using Stay-In-Place Metal Forms And Epoxy-Coated Reinforcement, Nabil Grace, James L. Hanson, Hany I. Abdelmessih Oct 2004

Inspection And Deterioration Of Bridge Decks Constructed Using Stay-In-Place Metal Forms And Epoxy-Coated Reinforcement, Nabil Grace, James L. Hanson, Hany I. Abdelmessih

Civil and Environmental Engineering

A comprehensive research investigation was conducted to evaluate the use of Stay-in-Place Metal Forms (SIPMFs) in construction of concrete bridge decks. The objectives of this research project were to establish the state-of-the-practice for use and performance of SIPMFs for bridge decks, to evaluate the field performance of bridge decks with and without SIPMFs, and to investigate the behavior of environmentally conditioned large-scale laboratory bridge deck specimens with and without SIPMFs. A survey was developed and administered to all DOTs to examine the state-of-the-practice of using SIPMFs for concrete bridge deck construction. Additionally, a field investigation was conducted to evaluate the …


Bracing Requirements Of Cfs Cee-Studs Subjected, Perry S. Green, Thomas Sputo, Viswanath Urala Oct 2004

Bracing Requirements Of Cfs Cee-Studs Subjected, Perry S. Green, Thomas Sputo, Viswanath Urala

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.


State Traffic Volume Systems Count Estimation Process, Doug Kreis, Angie Quigley Oct 2004

State Traffic Volume Systems Count Estimation Process, Doug Kreis, Angie Quigley

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet has an immense traffic data collection program that is an essential source for many other programs. The Division of Planning processes traffic volume counts annually. These counts are maintained in the Counts Database (CTS), which contains over 20,000 separate station locations and some traffic counts from as early as 1963.

The Division of Planning currently collects traffic volume counts for all non-interstate routes on a revolving three year basis. Years wherein actual counts are not performed are supplemented with estimates generated by a FORTRAN program. Estimates are projected using prior actual counts by weighted linear regression …


Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana Oct 2004

Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana

Mechanical & Aerospace Engineering Theses & Dissertations

Despite numerous investigations devoted to its scrutiny, injury causing mechanism associated with rear-end impact collision producing injury such as Whiplash Associated Disorder (WAD) has remained a mystery. Several criteria have been proposed to predict the injury causing mechanism, but none have been universally accepted. The challenge lies in determining a set of testing procedures representative of real-world collisions, wherein the results obtained are not only the same as human testing, but remain consistent with various subjects and impact conditions. It is hypothesized that one of the most important considerations is the effect of initial seated position (ISP).

This thesis can …