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Missouri University of Science and Technology

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Articles 391 - 420 of 1051

Full-Text Articles in Civil Engineering

Estimation Of Earthquake Loss Due To Bridge Damage In The St. Louis Metropolitan Area: Part I - Direct Losses, Ronaldo Luna, David J. Hoffman, William T. Lawrence Jan 2008

Estimation Of Earthquake Loss Due To Bridge Damage In The St. Louis Metropolitan Area: Part I - Direct Losses, Ronaldo Luna, David J. Hoffman, William T. Lawrence

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The risk associated with earthquake hazards on highway systems is dependent on the complexity of a network and its redundancy in providing traffic flow. Earthquake loss estimation studies can provide decision makers with an appreciation of the importance of having a highway network resistant to earthquakes and information to make the network resistant to these events. The direct economic loss was estimated for a major metropolitan area, St. Louis, for a series of earthquake scenarios. The primary component of the study was damage to bridges within the highway system. The study zone covers the St. Louis metropolitan area and its …

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Development Of Ballistic Limit Equations For Dual-Wall Spacecraft Shielding: A Concise History And Suggestions For Future Development, William P. Schonberg Jan 2008

Development Of Ballistic Limit Equations For Dual-Wall Spacecraft Shielding: A Concise History And Suggestions For Future Development, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

All earth-orbiting spacecraft are susceptible to impacts by orbital debris particles, which can occur at extremely high speeds and can damage flight- and mission-critical systems. The traditional damage mitigating shield design for this threat consists of a “bumper” that is placed at a relatively small distance away from the main “inner wall” of the spacecraft. The performance of a hypervelocity impact shield is typically characterized by its ballistic limit equation, which is typically drawn as a line of demarcation between regions of rear-wall perforation and no perforation; when graphically represented, it is often referred to as a ballistic limit curve. …

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Rational Best-Value Model Based On Expected Performance, Magdy Abdelrahman, Tarek Zayed, Jay Hietpas, Ahmed Elwakil Jan 2008

Rational Best-Value Model Based On Expected Performance, Magdy Abdelrahman, Tarek Zayed, Jay Hietpas, Ahmed Elwakil

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The best-value procurement strategy is gaining the interest of federal and state agencies. The strategy increases the value added to a project for each dollar added. A new concept of best value, that is, a rational and flexible model based on expected performance, is presented. The model's flexibility is obvious in the selection of parameters to be included in the contractor selection process and in the determination of their weights. The model's rationality will be achieved through relating all awarded scores to the agency's expected performance. The establishment of the best-value model relies on the past record of the contractor's …

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Estimation Of Earthquake Loss Due To Bridge Damage In The St. Louis Metropolitan Area. Ii: Indirect Losses, David Lee Enke, Chakkaphan Tirasirichai, Ronaldo Luna Jan 2008

Estimation Of Earthquake Loss Due To Bridge Damage In The St. Louis Metropolitan Area. Ii: Indirect Losses, David Lee Enke, Chakkaphan Tirasirichai, Ronaldo Luna

Engineering Management and Systems Engineering Faculty Research & Creative Works

An approach to estimate the indirect economic loss due to damaged bridges within the highway system from an earthquake event is presented. The indirect cost considered refers to the increased highway transportation cost only. The study zone covers the St. Louis metropolitan area and its surrounding suburban regions. An earthquake scenario centered in St. Louis, with a magnitude 7.0 is used. The direct earthquake loss was primarily damage to bridges, which causes an increase in travel time and distance within the transportation network. This information is then used as input for the indirect loss model. The indirect loss is examined …

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Field And Laboratory Investigation Of Ozone-Indoor Surface Reactions: Secondary Emissions Inventory And Implications For Indoor Air Quality, Hong Wang Jan 2007

Field And Laboratory Investigation Of Ozone-Indoor Surface Reactions: Secondary Emissions Inventory And Implications For Indoor Air Quality, Hong Wang

Doctoral Dissertations

"Interfacial chemistry greatly influences human exposure to reactants and products in indoor environments. Emissions of volatile organic compounds, as a result of ozone-surface interactions, can lower an occupant's exposure to ozone, but increase indoor concentrations of odorous and carcinogenic compounds. Therefore, investigation of ozone-surface interactions are necessary for better understanding and controlling exposure to ozone and the products of indoor surface chemistry. In this dissertation, field experiments were conducted in five homes in three seasons to quantify ozone-initiated secondary emission rates (SERs), yields surface reaction probabilities and study their temporal trends"--Abstract, page iv.

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The Leaching Behavior Of Arsenic, Selenium And Other Trace Elements In Coal Fly Ash, Tian Wang Jan 2007

The Leaching Behavior Of Arsenic, Selenium And Other Trace Elements In Coal Fly Ash, Tian Wang

Doctoral Dissertations

"The goals of this study are four fold, they are: (1) to investigate the leaching behavior of arsenic and selenium from fly ash as well as their affecting factors; (2) to analyze the speciation of arsenic and selenium in fly ash leachate; (3) to develop a modeling approach to quantify the availability and stability of trace cationic elements in fly ash; (4) to apply this model to describe the leaching/adsorption behavior of arsenic and selenium on fly ash, as well as the calcium effect on arsenic (V) adsorption process"--Abstract, page iv.

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Experimental And Analytical Evaluation Of Frp-Confined Large Size Reinforced Concrete Columns, Silvia Rocca Jan 2007

Experimental And Analytical Evaluation Of Frp-Confined Large Size Reinforced Concrete Columns, Silvia Rocca

Doctoral Dissertations

"Fiber Reinforced Polymer (FRP) jacketing of Reinforced Concrete (RC) columns, as a rapidly growing strengthening technique, requires appropriate design methods. However, the current available design guides are based on models, in their majority semi-empirical, and calibrated with small-scale plain concrete specimens. These models might not be reliable in predicting the strength and ductility enhancement sought through FRP-confinement in RC columns with geometric and material properties as found in practice. This dissertation presents the research conducted in three technical papers. In the first paper, the performance of 22 FRP-wrapped RC columns of medium- and large-scale is studied. The results of the …

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Static Evaluation Of The Out-Of-Plane Behavior Of Urm Infill Walls Utilizing Modern Blast Retrofit Systems, Trevor D. Hrynyk Jan 2007

Static Evaluation Of The Out-Of-Plane Behavior Of Urm Infill Walls Utilizing Modern Blast Retrofit Systems, Trevor D. Hrynyk

Masters Theses

"Previous investigations have shown that the use of modern retrofit systems can significantly improve the behavior of URM infill walls subjected to variable out-of-plane loads. It has also been shown that the use of externally bonded retrofit systems can greatly reduce the amount of fragmentation and debris scatter that is found to occur in URM walls subjected to high intensity blast loads...The main objective of this study is to investigate, through static testing, the use of modern materials for the purpose of improving the behavior of URM walls subjected to blast loads. This study implemented externally bonded FRP grids and …

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Analysis Of Soil Erosion Based On Soil Properties, Preetha Veeraraghavan Jan 2007

Analysis Of Soil Erosion Based On Soil Properties, Preetha Veeraraghavan

Masters Theses

"The objectives of this research were to identify the major soil parameter(s) that affect the erosion rate of soil and to estimate the erosion rate based on those soil parameters. Both prepared samples and natural samples were used in this research. The soil properties analyzed were the water content, unit weight, Atterberg limits, and soil cohesion. The erosion rate was determined using a rectangular flume and a linear relation between the erosion rate and shear stress was established from the flume experiment. The slope of the linear relation was a good indicator of the soil's erosion rate. The erosion rate …

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Análisis De Deslizamientos En La Ciudad Capital Utilizando Sistemas De Información Geográfica, Pedro Pablo Conlledo, Ronaldo Luna Jan 2007

Análisis De Deslizamientos En La Ciudad Capital Utilizando Sistemas De Información Geográfica, Pedro Pablo Conlledo, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

En Guatemala, los daños ocasionados por deslizamientos de tierra son innumerables, y sin embargos son pocos los esfuezos que se han hecho a nivel nacional por estudiarlos. El principal objetivo de este trabajo fue utilizar Sistemas de lnformacion Geografica (SlG) para estudiar sistematicamente la ocurrencia de deslizamientos en el Departamento de Guatemala con la informacion disponible.

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Enhanced Electronic Conductivity In Si-Substituted Calcium Aluminate, Julia E. Medvedeva, Thomas O. Mason, Kenneth R. Poeppelmeier, Mariana I. Bertoni, Arthur J. Freeman Jan 2007

Enhanced Electronic Conductivity In Si-Substituted Calcium Aluminate, Julia E. Medvedeva, Thomas O. Mason, Kenneth R. Poeppelmeier, Mariana I. Bertoni, Arthur J. Freeman

Physics Faculty Research & Creative Works

Improved conductivity has been achieved by controllable substitution of an ultraviolet electronic conductor. The transparent conducting oxide system, H-doped Ca12Al(14−x)SixO(33+x/2) with x=0−4, exhibits a conductivity strongly dependent on the substitution level. Four-point direct current conductivity increases with x from 0.15 to 0.61 S/cm at room temperature. The observed conductivity behavior is consistent with the predictions of our first principles density functional calculations for the Si-substituted system with x=0, 2, and 4. Furthermore, the Seebeck coefficient is composition dependent suggesting the existence of an activated mobility associated with small polaron conduction. ©2007 American Institute of Physics

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Performance Evaluation Of Existing Analytical Methods To Compute The Shear Contribution Provided By Externally Bonded Frp Sheets In Concrete Structures, Rocio Patricia Tumialan Jan 2007

Performance Evaluation Of Existing Analytical Methods To Compute The Shear Contribution Provided By Externally Bonded Frp Sheets In Concrete Structures, Rocio Patricia Tumialan

Masters Theses

"External application of FRP composites has been adopted for strengthening and/or repair of concrete structures in many applications during the last two decades. However, the research into shear strengthening using FRP composites has not been widely conducted as compared to flexural strengthening and axial load capacity increase, and the results obtained thus far are scarce and sometimes controversial. This study presents a review of analytical studies and design guidelines on shear strengthening of concrete structures with externally-bonded FRP laminates, and their assessment with experimental data collected from the literature. The strengths and weaknesses of each model and design guidelines/codes/specifications are …

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Innovative Solutions In Bridge Construction, Rehabilitation, And Structural Health Monitoring, Fabio Matta Jan 2007

Innovative Solutions In Bridge Construction, Rehabilitation, And Structural Health Monitoring, Fabio Matta

Doctoral Dissertations

"This dissertation includes three technical papers that investigate the development of innovative technologies for bridge construction, rehabilitation, and structural health monitoring, respectively, at different stages of the technology transfer process...The research impact is twofold: first is the introduction of promising innovative technologies in development and implementation projects with the direct involvement of forward-thinking industry partners; second is the demonstration of the validity of these technologies on the basis of a rigorous scientific approach"--Abstract, page iv.

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Using Coupled Eulerian And Lagrangian Grids To Model Explosive Interactions With Buildings, Braden Lusk, William P. Schonberg, Jason Baird, Robert S. Woodley, Warren Noll Nov 2006

Using Coupled Eulerian And Lagrangian Grids To Model Explosive Interactions With Buildings, Braden Lusk, William P. Schonberg, Jason Baird, Robert S. Woodley, Warren Noll

Mining Engineering Faculty Research & Creative Works

This paper presents the development of a computational model that can be used to study the interactions between structures and detonating explosives contained within them. This model was developed as part of an effort to develop a rubble characterization model for use in AmmoSIM, an agent based urban tactical decision aid (UTDA) software for weapon-target pairing. The rubble pile created following the collapse of a building in a combat situation can significantly impact mission accomplishment, particularly in the area of movement and maneuver. The information provided by AmmoSIM will enable both platoon level and command center staff to make informed …

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Rubble Pile Characterization Model, William P. Schonberg, Jason Baird, Paul Nicholas Worsey, Abdeldjelil Belarbi, Roger A. Laboube, Braden Lusk, R. Flanagan, H. Burleson, Robert S. Woodley, Warren Noll Jul 2006

Rubble Pile Characterization Model, William P. Schonberg, Jason Baird, Paul Nicholas Worsey, Abdeldjelil Belarbi, Roger A. Laboube, Braden Lusk, R. Flanagan, H. Burleson, Robert S. Woodley, Warren Noll

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rubble piles created following the collapse of a building in a combat situation can significantly impact mission accomplishment, particularly in the area of movement and maneuver. Rubble characteristics must be known, for example, in order to predict the ability of a vehicle to override the collateral damage from weapon effects in urban areas. Two types of models are developed: a first-order model and a first-principles-based model. In both models, we assume complete rubblization of the building and develop a rubble profile model using the size and composition of the collapsed structure to predict the rubble volume. In both cases, this …

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Calibration Of The Corelok Method For Determination Of Missouri Aggregate Specific Gravities, David Newton Richardson, S. M. Lusher Jun 2006

Calibration Of The Corelok Method For Determination Of Missouri Aggregate Specific Gravities, David Newton Richardson, S. M. Lusher

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Specific gravity and absorption are fundamental aggregate properties needed for hot-mix asphalt (HMA) and Portland cement concrete (PCC) mix design and/or volumetric determinations. MoDOT utilizes the American Association of State Highway and Transportation Officials (AASHTO) standard test methods T 84 (for fine aggregates) and T 85 (for coarse aggregates) to determine these important properties. Criticisms of these procedures are the subjective nature of determining when the aggregates have reached the saturated, surface-dry (SSD) condition (especially T 84) and the substantial amount of time needed to complete the tests. The CoreLok method addresses these criticisms in that it is an objective …

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Semiempirical Electromagnetic Modeling Of Crack Detection And Sizing In Cement-Based Materials Using Near-Field Microwave Methods, Jagadish Nadakuduti, Genda Chen, R. Zoughi Apr 2006

Semiempirical Electromagnetic Modeling Of Crack Detection And Sizing In Cement-Based Materials Using Near-Field Microwave Methods, Jagadish Nadakuduti, Genda Chen, R. Zoughi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Detection and characterization of cracks in cement-based materials is an integral part of damage evaluation for health monitoring of civil structures. Microwave signals are able to penetrate inside of dielectric materials (e.g., cement-based materials) and are sensitive to local, physical, geometrical, and dielectric variations in a structure. This makes microwave nondestructive testing and evaluation (NDT&E) techniques suitable for inspection and health monitoring of civil structures. Near-field microwave NDT&E techniques offer the added advantage of providing high spatial resolution, requiring simple hardware that may be portable, low power, fast, real time, and robust. Additionally, these techniques are noncontact and one-sided. Besides …

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Earthquake Hazard Input For Loss Estimation Study: St. Louis Highway System, Ronaldo Luna, David J. Hoffman, William T. Lawrence Jan 2006

Earthquake Hazard Input For Loss Estimation Study: St. Louis Highway System, Ronaldo Luna, David J. Hoffman, William T. Lawrence

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The long recurrence period and high consequence earthquakes events in the New Madrid Seismic Zone have caused some federal agencies (e.g., NEHRP, FHWA) to look at the more densely populated areas where higher seismic risk is present. This paper presents the data collection, interpretation, and analysis of the geotechnical information required for an earthquake loss estimation study in St. Louis metro area. The loss estimation study was limited to the highway transportation system, where only the major highways were considered. The project information was processed using a GIS, and the subsequent loss analysis was executed using the HAZUS-MH program.

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Liquefaction Effects On Lateral Pile Behavior For Bridges, Wei Zheng, Ronaldo Luna Jan 2006

Liquefaction Effects On Lateral Pile Behavior For Bridges, Wei Zheng, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A coupled pile-soil-structure interaction (SPSI) analysis method is presented to study the liquefaction effects on lateral pile behavior of the highway bridges. Pile-soil interaction is simulated by the dynamic nonlinear p-y method including the effect of liquefaction. The liquefaction effects to the pile-soil interaction are taken into account by introducing a degradation multiplier to the p-y curve. The degradation multiplier is related to the excess pore water pressure buildup at the pile-soil interface. The SPSI analysis method is implemented into a Missouri highway bridge site near the New Madrid Seismic Zone (NMSZ) rift complex for future earthquake scenarios of Mw …

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Systems Approach For Estimating Field Moisture Content, Thomas M. Petry, Yuh-Puu Han, David Newton Richardson Jan 2006

Systems Approach For Estimating Field Moisture Content, Thomas M. Petry, Yuh-Puu Han, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper describes a software tool developed for estimation of the field moisture content of subgrade materials. Subgrade behavior is directly related to its moisture content. Unfortunately, some approaches of estimating field moisture content are too complex to be used in routine design. In this paper, the authors attempt to provide an approach that is easy to use. The software presented here was developed using expert system approaches. It is capable of analyzing data entered by the users, and providing estimations to meet different scenarios. The information entered by the user is first examined for its reasonableness and accuracy. Then, …

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Transverse-Earthquake Induced Deformations Of A Bridge Approach Embankment In The New Madrid Seismic Zone, Wanxing Liu, Richard Wesley Stephenson, Ronaldo Luna Jan 2006

Transverse-Earthquake Induced Deformations Of A Bridge Approach Embankment In The New Madrid Seismic Zone, Wanxing Liu, Richard Wesley Stephenson, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

It is predicted that strong earthquakes, larger than M 7.0, may occur within next 50 years in the New Madrid Seismic Zone (NMSZ), the location of three of the most powerful earthquakes in United States history. Large displacements may occur during strong earthquakes that can cause an embankment to fail or lose its function. The hyperbolic stress-strain model with Masing rules was modified to account for strength and stiffness reduction due to change in the effective confining pressure. The Byrne model was combined with a hyperbolic model to calculate the pore water pressure caused by seismic shaking. This modified hyperbolic …

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Origin-Destination (O-D) Trip Table Estimation Using Traffic Movement Counts From Vehicle Tracking System At Intersection, S. Lee, Hojong Baik Jan 2006

Origin-Destination (O-D) Trip Table Estimation Using Traffic Movement Counts From Vehicle Tracking System At Intersection, S. Lee, Hojong Baik

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A new video-based vehicle tracking system is proposed to provide accurate information on directional traffic counts at intersections. The extracted counts are fed to estimate an origin- destination trip table which is necessary information for traffic impact study and transportation planning. The system utilizes a fisheye lens to expand the area covered by a single camera and uses a particle filtering method to track an individual vehicle. The filter is designed to handle environmental changes and multiple motion dynamics. Experimental results show its strong ability on tracking in various conditions. The paper shows how to use the tracking outputs in …

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Strength And Durability Characteristics Of A 70% Ground Granulated Blast Furnace Slag (Ggbfs) Concrete Mix, David Newton Richardson Jan 2006

Strength And Durability Characteristics Of A 70% Ground Granulated Blast Furnace Slag (Ggbfs) Concrete Mix, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For a bridge pier and abutment mass concrete project, three mixes were studied: an ordinary portland cement (OPC) mix (Type I PC) and two 70% by weight ground granulated blast furnace slag (GGBFS) mixes (Type II Low Heat PC). One of the slag mixes contained a high range water reducer (HRWR). Tests for compressive strength, freezethaw durability, rapid chloride permeability, and salt scaling were conducted on field samples. Results showed that the strengths of the slag mixes were lower than the OPC mix at all ages up to one year, although the use of HRWR did improve the strength somewhat. …

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Controlling Performance Of Crumb Rubber-Modified Binders Through Addition Of Polymer Modifiers, Magdy Abdelrahman Jan 2006

Controlling Performance Of Crumb Rubber-Modified Binders Through Addition Of Polymer Modifiers, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of tire rubber as a modifier to enhance the properties of asphalt mixes through the wet process has proved to be a successful procedure, but full control of the properties of crumb rubber-modified binders has been a challenge. The literature indicates a wide variation on adding rubber to asphalt and that the degree of success of rubber modification in AC mixes depends on several factors, the majority of which relate to the method of mixing, storing, and transporting and to construction technologies. Understanding the nature of the interaction process between asphalt cement and crumb rubber-modifier (CRM) helps explain …

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Effectiveness Of Open-Graded Base Layer On Subgrade Moisture Regime And Overall Pavement Performance, Hassan Salem, Fouad Bayomy, Robert Smith, Magdy Abdelrahman Jan 2006

Effectiveness Of Open-Graded Base Layer On Subgrade Moisture Regime And Overall Pavement Performance, Hassan Salem, Fouad Bayomy, Robert Smith, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rockcap (open-graded crushed aggregate with a nominal maximum size of 2.5 in.) base layer is commonly used in the construction of asphalt pavements in Idaho. The effectiveness of the rockcap layer on the subgrade moisture regime and the overall pavement performance were evaluated. Two pavement sites were selected in northern and southern regions of the state. At each site, two pavement sections that are identical and adjacent to each other were instrumented by temperature, frost, and moisture sensors using time domain reflectometry (TDR) probes. One was constructed by a well-graded 3/4-in. aggregate base, whereas the other was constructed by the …

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Improving Prediction Accuracy In Mechanistic-Empirical Pavement Design Guide, Scott Schram, Magdy Abdelrahman Jan 2006

Improving Prediction Accuracy In Mechanistic-Empirical Pavement Design Guide, Scott Schram, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Model calibration plays a fundamental role in the implementation of the mechanistic-empirical pavement design guide. The data used in the default calibration effort, which were afforded by the Long Term Pavement Performance (LTPP) database, have a network-level inference space. As implementation proceeds, state highway agencies may be inclined to calibrate at a local network level. However, with a focus on the calibration data set to local project-level conditions, model prediction error can be reduced further. Under this study, Nebraska Department of Roads Pavement Management System data were used to calibrate two design guide smoothness models at the local project level. …

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Novel Distributed Cable Sensors For Detection Of Cracks In Rc Structures, Genda Chen, David Pommerenke Aug 2005

Novel Distributed Cable Sensors For Detection Of Cracks In Rc Structures, Genda Chen, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, the development of a fundamentally new, topology-based cable sensor design concept is summarized for crack detection in reinforced concrete (RC) structures. The sensitivity, spatial resolution, and signal loss of sensors are investigated both numerically and experimentally. Two sensors were fabricated and validated with small- and large-scale laboratory tests under different loads. Both were proven sensitive to crack of various sizes from visually undetectable to excessive, giving the location and severity of damage simultaneously. One sensor has been installed on a three-span bridge for its long-term monitoring. It is capable of recording damage that has occurred during a …

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Aggregate Gradation Optimization -- Literature Search, David Newton Richardson Jan 2005

Aggregate Gradation Optimization -- Literature Search, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

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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 …

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Spatial Bioaccumulation Modeling In A Network Of Bayous, Ronaldo Luna, Karen H. Watanabe, Andrew J. Wilding Jan 2005

Spatial Bioaccumulation Modeling In A Network Of Bayous, Ronaldo Luna, Karen H. Watanabe, Andrew J. Wilding

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A software system, Spatial Network Bioaccumulation Model (SNBM), was developed to model the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in aquatic food webs. The SNBM uses a geographic information system as an engine to: (i) store the spatial representation of input parameters (the data related to the ecosystem), (ii) transfer input and output data to and from the food-web bioaccumulation model, and (iii) display the predicted food-web organism concentrations over a base map of the field site. The bioaccumulation model is a time-dependent, set of first-order ordinary differential equations that are solved numerically. Many sampling locations can be analyzed using …

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