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Role Of Higher-"Mode" Pushover Analyses In Seismic Analysis Of Buildings, Rakesh K. Goel, Anil K. Chopra Nov 2005

Role Of Higher-"Mode" Pushover Analyses In Seismic Analysis Of Buildings, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

The role of higher-“mode” pushover analyses in seismic analysis of buildings is examined in this paper. It is demonstrated that the higher-“mode” pushover curves reveal plastic hinge mechanisms that are not detected by the first-“mode” or other FEMA-356 force distributions, but these purely local mechanisms are not likely to develop during realistic ground motions in an otherwise regular building without a soft and/or weak story. Furthermore, the conditions necessary for “reversal” of a higher-“mode” pushover curve are examined. It is shown that “reversal” in a higher-“mode” pushover curve occurs after formation of a mechanism if the resultant force above the …


2005 Indiana County Highway Departments Bridge Replacement Cost Estimation Procedures, Indiana Ltap Nov 2005

2005 Indiana County Highway Departments Bridge Replacement Cost Estimation Procedures, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

This report is intended to provide county bridge officials a simple, straight forward method to estimate the costs of replacing county bridges. The report uses information from bridges constructed from 1997 through 2005, which was obtained through surveys completed by Indiana counties. Regressions were performed on the data and a spreadsheet prepared that allows users to input Average Daily Traffic (ADT) and the old bridge length to obtain an estimate for the cost of a replacement bridge.


Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez Oct 2005

Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez

Publications and Research

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally …


Use Of 16s Rrna Gene Terminal Restriction Fragment Analysis To Assess The Impact Of Solids Retention Time On The Bacterial Diversity Of Activated Sludge, Pascal E. Saikaly, Peter George Stroot, Daniel B. Oerther Oct 2005

Use Of 16s Rrna Gene Terminal Restriction Fragment Analysis To Assess The Impact Of Solids Retention Time On The Bacterial Diversity Of Activated Sludge, Pascal E. Saikaly, Peter George Stroot, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes was used to investigate the reproducibility and stability in the bacterial community structure of laboratory-scale sequencing batch bioreactors (SBR) and to assess the impact of solids retention time (SRT) on bacterial diversity. Two experiments were performed. In each experiment two sets of replicate SBRs were operated for a periods of three times the SRT. One set was operated at an SRT of 2 days and another set was operated at an SRT of 8 days. Samples for T-RFLP analysis were collected from the two sets of replicate reactors. HhaI, …


Loss Functions And Framework For Regional Flood Damage Estimation In Residential Area, Jui-Lin Kang, Ming-Daw Su, Ling-Fang Chang Sep 2005

Loss Functions And Framework For Regional Flood Damage Estimation In Residential Area, Jui-Lin Kang, Ming-Daw Su, Ling-Fang Chang

Journal of Marine Science and Technology–Taiwan

The risks of flooding damages for a region increase as the population and economy development increased in that area. Damage assessment and risk analysis are important issues for risk management and hazard mitigation. There are huge amount of data involved in the process of regional damage assessment and most of these data are spatially and temporally distributed. This paper focuses on the use of spatial data for capture of spatial characteristics of damage in natural calamities. Because it affects a large number of persons and families, flood damages in the residential area usually attract major attentions in regional flood hazard …


A Grid-Based Gis Approach To Regional Flood Damage Assessment, Ming-Daw Su, Jui-Lin Kang, Ling-Fang Chang, Albert S Chen Sep 2005

A Grid-Based Gis Approach To Regional Flood Damage Assessment, Ming-Daw Su, Jui-Lin Kang, Ling-Fang Chang, Albert S Chen

Journal of Marine Science and Technology–Taiwan

Regional flood risk assessment is the base for a sound and comprehensive risk planning or management. The regional flood loss is the sum of the damages in all the flooded parcels. The data involved in this process are multifarious and difficult to establish and maintain especially in the developing countries that suffer most often from the flood hazard. A grid-based GIS approach to regional flood damage assessment is proposed in this paper. Aggregated census data that are relatively available were used instead of the data at parcel level. An algorithm was proposed to disaggregated these aggregated census data into spatially …


Identification Of Rear-End Crash Patterns On Instrumented Freeways: A Data Mining Approach, A. Pande, M. Abdel-Aty Sep 2005

Identification Of Rear-End Crash Patterns On Instrumented Freeways: A Data Mining Approach, A. Pande, M. Abdel-Aty

Civil and Environmental Engineering

Data mining is the analysis of large “observational” datasets to find unsuspected relationships that might be useful to the data owner. It typically involves analysis where objectives of the mining exercise have no bearing on the data collection strategy. Freeway traffic surveillance data collected through underground loop detectors is one such “observational” database maintained for various ITS (Intelligent Transportation Systems) applications such as travel time prediction etc. In this research data mining process is used to relate this surrogate measure of traffic conditions (data from freeway loop detectors) with occurrence of rear-end crashes on freeways. The results from this analysis …


Analysis Of Per Capita Expenditures Of Suburbanizing Communities In Maine, New England Environmental Finance Center Sep 2005

Analysis Of Per Capita Expenditures Of Suburbanizing Communities In Maine, New England Environmental Finance Center

Economics and Finance

This study analyzes per capita expenditure trends among selected fast-growing Maine towns from 1970-2004. The ten communities studied are termed as “suburbanizing” towns. This term is used to describe towns that over the past 30-40 years have been in the process of transition from rural to suburban – in terms of their population and housing densities, their forms of government, and the services they provide, as well as other characteristics.1 Such towns are of particular interest because they have been absorbing a healthy percentage of the state’s population growth during this time period, often at the expense of Maine’s service …


Development Of Finite Element Method-Based Model Equations For Hollow Tapered Poles, Jiwon Jung Aug 2005

Development Of Finite Element Method-Based Model Equations For Hollow Tapered Poles, Jiwon Jung

Civil Engineering Dissertations - Archive

This study presents the development of three-parameter load-deflection models for steel and FRP poles commonly used to support closed circuit television cameras. An experimental investigation is carried out to obtain static load-deflection characteristics of tapered octagonal steel cross section and circular FRP cross section poles. Numerical results generated from three-dimensional isoparametric finite element model (FEM) considering coupled nonlinear algorithms for material, geometric, contact, and pre-tensioning effects are compared with those obtained experimentally. Eight-node elsto-plastic solid element is employed to model the pole, end-plate, bolts, concrete base, and laboratory reaction floor. The laboratory reaction floor is modeled with a thick plate …


Nonlinear Finite Element Model Analysis Of Human Accommodation Lens, Tri Le Aug 2005

Nonlinear Finite Element Model Analysis Of Human Accommodation Lens, Tri Le

Civil Engineering Theses - Archive

The crystalline human lens is modeled by using the finite element software, ABAQUS/CAE Version 6.5-1 as an axisymmetric shell to study the optical power and displacement of anterior and posterior poles induced due to zonule traction. Several different element types were tested to obtain the optimum mesh. These elements were three and six-noded triangular hybrid and four-noded quadrilateral hybrid for modeling of the cortex and nucleus. Constant strain triangular and regular quadrilateral elements were examined for modeling the capsule. One dimensional two degree of freedom spring elements were used to model the anterior, posterior, and equatorial zonules. Five different lens …


Stochastic Modeling Of The Permeability Of Randomly Generated Porous Media, Yusong Li, Eugene Leboeuf, P. K. Basu, Sankaran Mahadevan Aug 2005

Stochastic Modeling Of The Permeability Of Randomly Generated Porous Media, Yusong Li, Eugene Leboeuf, P. K. Basu, Sankaran Mahadevan

Department of Civil and Environmental Engineering: Faculty Publications

Permeability of porous media in subsurface environments is subject to potentially large uncertainties due to the heterogeneity of natural systems. In this study, a first-order reliability method (FORM) is combined with a lattice Boltzmann method (LBM) to estimate the permeability of randomly generated porous media. The proposed procedure provides an increased ease of addressing complex pore structures by employing LBM to model fluid flow, while inheriting the computational efficiency from FORM. Macroscale- equivalent permeability can thus be estimated with significantly reduced computational efforts, while maintaining a connection to the complex microscale fluid dynamics within a pore structure environment. Implemented on …


Annual Exceedance Probability Analysis, Masako Amai Gardner Jul 2005

Annual Exceedance Probability Analysis, Masako Amai Gardner

Theses and Dissertations

Annual Exceedance Probability (AEP) is the method used by U.S. Army Corps of Engineers (USACE) to determine the probability of flooding caused by the failure of a levee or other flood control structure. This method shows the probability of flooding only at one particular location at a time. In order to overcome the limitation of AEP, a new method of studying flood probability, called an AEP map, was presented. By using hydrologic and hydraulic modeling software, an AEP map can be created to determine and visualize the spatial distribution of the probability of flooding. An AEP map represents a continuous …


Establishing Public Confidence In The Viability Of Fingerprint Biometric Technology, Nathan Alan Green Jul 2005

Establishing Public Confidence In The Viability Of Fingerprint Biometric Technology, Nathan Alan Green

Theses and Dissertations

The most common personal authentication techniques used for identity management employ a secret PIN or password that must be remembered. The challenge, for a given user, is that a multitude of such codes must be recalled over the course of the day for transactions involving distinct computer applications. Password mania prevails. Fingerprint biometric technology is an ideal alternate solution to this password recall problem. In spite of their availability for nearly thirty years, fingerprint biometric systems still remain uncommon in public sectors of industry such as education, government, and technology. Technology has improved sufficiently that false acceptance and rejection rates …


Evaluation Of Accuracy And Efficiency Of Some Simulation And Sampling Methods In Structural Reliability Analysis, Christopher D. Eamon, Michel D. Thompson, Zhenyu Liu Jul 2005

Evaluation Of Accuracy And Efficiency Of Some Simulation And Sampling Methods In Structural Reliability Analysis, Christopher D. Eamon, Michel D. Thompson, Zhenyu Liu

Civil and Environmental Engineering Faculty Research Publications

Numerous simulation and sampling methods can be used to estimate reliability index or failure probability. Some point sampling methods require only a fraction of the computational effort of direct simulation methods. For many of these methods, however, it is not clear what trade-offs in terms of accuracy, precision, and computational effort can be expected, nor for which types of functions they are most suited. This study uses nine procedures to estimate failure probability and reliability index of approximately 200 limit state functions with characteristics common in structural reliability problems. The effects of function linearity, type of random variable distribution, variance, …


Upper Spokane River Model In Idaho: Boundary Conditions And Model Setup And Calibration For 2001 And 2004, Robert Leslie Annear, Scott A. Wells, Chris Berger Jul 2005

Upper Spokane River Model In Idaho: Boundary Conditions And Model Setup And Calibration For 2001 And 2004, Robert Leslie Annear, Scott A. Wells, Chris Berger

Civil and Environmental Engineering Faculty Publications and Presentations

As a result of a Total Maximum Daily Load (TMDL) study of the Spokane River in Washington, a hydrodynamic and water quality model for the Spokane River was developed by Portland State University (PSU) for the Corps of Engineers and the Washington Department of Ecology from the Washington-Idaho state line to the outlet of Long Lake.

An earlier study of the Spokane River was undertaken by Limno-Tech (2001a, 2001b) for the domain shown in Figure 3. Limno-Tech used an earlier version of CE-QUAL-W2, Version 2, for the Reservoir portion of the Spokane River from Post Falls Dam to Coeur d’Alene …


Lake Whatcom Water Quality Model, Chris Berger Jul 2005

Lake Whatcom Water Quality Model, Chris Berger

Civil and Environmental Engineering Faculty Publications and Presentations

A water quality model of Lake Whatcom, Washington was developed as part of a Total Maximum Daily Load Study for the Washington Department of Ecology. Lake Whatcom is a large natural lake which is listed on the 1998 Washington State 303(d) list of waterbodies which do not meet the criterion for dissolved oxygen. Located next to the city of Bellingham, it is approximately 10 miles long and has a surface area of approximately 5000 acres and a maximum depth of over 100 meters. Eutrophication processes in the lake have been accelerated in recent years perhaps by the availability of nutrients …


Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi Jul 2005

Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Artificial neural networks have proven to be an attractive mathematical tool to represent complex relationships in many branches of hydrology. Due to this attractive feature, neural networks are increasingly being applied in subsurface modeling where intricate physical processes and lack of detailed field data prevail. In this paper, a methodology using modular neural networks (MNN) is proposed to simulate the nitrate concentrations in an agriculture-dominated aquifer. The methodology relies on geographic information system (GIS) tools in the preparation and processing of the MNN input–output data. The basic premise followed in developing the MNN input–output response patterns is to designate the …


Baseline Modeling Of The Maysville Cable-Stayed Bridge Over The Ohio River, Issam E. Harik, Jindong Hu, Suzanne Weaver Smith, Wei-Xin Ren, Tong Zhao, Jennie E. Campbell, Clark Graves Jul 2005

Baseline Modeling Of The Maysville Cable-Stayed Bridge Over The Ohio River, Issam E. Harik, Jindong Hu, Suzanne Weaver Smith, Wei-Xin Ren, Tong Zhao, Jennie E. Campbell, Clark Graves

Kentucky Transportation Center Research Report

This report presents the baseline modeling of the Maysville cable-stayed bridge which connects Maysville, Kentucky and Aberdeen, Ohio over the Ohio River. The objective of this study is to establish the bridge baseline model via the dynamics-based technique and finite element method. The scope of research includes finite element modeling and modal analysis, field free vibration testing, finite element model calibration using field test results, and cable dynamic testing and modeling. It is demonstrated that a cable-stayed bridge is a highly pre-stressed structure. The stress stiffening of cable elements plays an important role in both static and dynamic analysis. The …


Waldo Lake Research In 2004, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Michelle Wood, Yangdong Pan, Robert Leslie Annear, Aaron Hook, Laura Johnson, Rich Miller, Amanda Murphy, Terry Stoltz Jun 2005

Waldo Lake Research In 2004, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Michelle Wood, Yangdong Pan, Robert Leslie Annear, Aaron Hook, Laura Johnson, Rich Miller, Amanda Murphy, Terry Stoltz

Center for Lakes and Reservoirs Publications and Presentations

The Willamette National Forest has worked with Portland State University, Center for Lakes and Reservoirs (PSU) and the University of Oregon (UO) to investigate ecosystem changes, provide guidance on long-term monitoring methods, assess monitoring data, develop predictive water quality models, and conduct research that will lead to better protection and understanding of the Waldo Lake ecosystem. This report summarizes the second year of collaborative PSU-UO research at Waldo Lake. Research has focused on understanding physical, chemical and biological characteristics of Waldo Lake across a range of spatial and temporal scales. Research tasks that continued from 2003 into 2004 included temperature …


Genetic Algorithms For Design Of Pipe Network Systems, Hong-Min Shau, Bi-Liang Lin, Wen-Chih Huang Jun 2005

Genetic Algorithms For Design Of Pipe Network Systems, Hong-Min Shau, Bi-Liang Lin, Wen-Chih Huang

Journal of Marine Science and Technology–Taiwan

In the last three decades, a significant number of methods for optimal design of pipe network systems have been developed using linear programming, non-linear programming, dynamic programming, enumeration techniques, and genetic algorithm (GA). This paper presents a genetic algorithm (GA) approach to the design of a pipe network systems. The objectives considered are minimization of the network cost in the practical requirement. Of all the preceding methods, GA based methods appear to be robust, as they can handle discrete pipes sizes with ease and produce a set of alternatives. By judgmentally selecting the Ruey-Fang district water supply system for the …


Condition Analysis Of Concrete Bridge Decks In Utah, Robert S. Tuttle Jun 2005

Condition Analysis Of Concrete Bridge Decks In Utah, Robert S. Tuttle

Theses and Dissertations

Concrete bridge decks in Utah are experiencing observable deterioration due primarily to freeze-thaw cycles and the routine application of deicing salts during winter maintenance activities. Given the need for increasingly cost-effective strategies for bridge deck maintenance, rehabilitation, and replacement (MR&R), the Utah Department of Transportation (UDOT) initiated this research to ultimately develop a protocol offering guidance as to whether deteriorated bridge decks should be rehabilitated or replaced. While threshold values for various non-destructive condition assessment methods were proposed in earlier UDOT research, this work focused on implementing the recommended test criteria. Twelve bridges were identified by UDOT engineers for inclusion …


Slides: Interstate Marketing And Similar Economic Approaches, Jim Booker Jun 2005

Slides: Interstate Marketing And Similar Economic Approaches, Jim Booker

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Jim Booker, Siena College.

27 slides.


Slides: Establish True Basin-Wide Institutions: The Return To The River Basin As The Unit Of Management, Charles W. (Chuck) Howe Jun 2005

Slides: Establish True Basin-Wide Institutions: The Return To The River Basin As The Unit Of Management, Charles W. (Chuck) Howe

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Charles Howe, University of Colorado.

13 pages and 10 slides.

Contains references.


Slides: Tightening Water Supplies, Kay Brothers Jun 2005

Slides: Tightening Water Supplies, Kay Brothers

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Kay Brothers, Southern Nevada Water Authority.

40 slides.


Slides: "Tightening Water Supplies”: Arizona And The Lower Basin States, Herb Guenther Jun 2005

Slides: "Tightening Water Supplies”: Arizona And The Lower Basin States, Herb Guenther

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Herb Guenther, Arizona Department of Water Resources.

31 slides.


Slides: So What If It’S Called “All-American”, Malissa Hathaway Mckeith, Bob Johnson Jun 2005

Slides: So What If It’S Called “All-American”, Malissa Hathaway Mckeith, Bob Johnson

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Malissa Hathaway McKeith, Lewis Brisbois Bisgaard & Smith LLP.

Respondent on US-Mexico Issues and Other Lower Basin Matters: Bob Johnson, US Bureau of Reclamation.

15 slides and 12 pages.

Contains references.


Slides: Do The Upper Basin States Have Enough Water To Grow?: Is There Enough Water To Go Around?, Don A. Ostler Jun 2005

Slides: Do The Upper Basin States Have Enough Water To Grow?: Is There Enough Water To Go Around?, Don A. Ostler

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Don A. Ostler, Upper Colorado River Commission.

24 slides.


Slides: Response Of The System To Various Hydrological And Operational Assumptions: Reclamation Modeling Results, Terry Fulp Jun 2005

Slides: Response Of The System To Various Hydrological And Operational Assumptions: Reclamation Modeling Results, Terry Fulp

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Terry Fulp, US Bureau of Reclamation.

43 slides.


Slides: Crss Lite: Screening Model For Operating Policy Evaluation And Negotiation On The Colorado River Basin, Carly Jerla Jun 2005

Slides: Crss Lite: Screening Model For Operating Policy Evaluation And Negotiation On The Colorado River Basin, Carly Jerla

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Carly Jerla, US Bureau of Reclamation.

17 slides.


Agenda: Hard Times On The Colorado River: Drought, Growth And The Future Of The Compact, University Of Colorado Boulder. Natural Resources Law Center, Western Water Assessment (Program), Colorado Water Conservation Board, Center For Advanced Decision Support For Water And Environmental Systems, Hydrosphere Resource Consultants, Rocky Mountain Mineral Law Foundation, Colorado Foundation For Water Education, Patrick, Miller & Kropf, P.C., William & Flora Hewlett Foundation Jun 2005

Agenda: Hard Times On The Colorado River: Drought, Growth And The Future Of The Compact, University Of Colorado Boulder. Natural Resources Law Center, Western Water Assessment (Program), Colorado Water Conservation Board, Center For Advanced Decision Support For Water And Environmental Systems, Hydrosphere Resource Consultants, Rocky Mountain Mineral Law Foundation, Colorado Foundation For Water Education, Patrick, Miller & Kropf, P.C., William & Flora Hewlett Foundation

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Sponsors and Contributors: Colorado Water Conservation Board, Center for Advanced Decision Support for Water and Environmental Systems, Western Water Assessment, CU-CIRES/NOAA, Hydrosphere Resource Consultants, Rocky Mountain Mineral Law Foundation, Colorado Foundation for Water Education, Patrick, Miller & Kropf, P.C., William and Flora Hewlett Foundation.

The Colorado River is approaching a crossroads. For the first time in its history, satisfying water demands in one state may require curtailing legally-recognized uses in another. This is not the first instance of water shortages in the region, and conflict among the seven Colorado River states is certainly not new. But the potential shortages on …