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Slides: Drought, Climate Change And Water Supply Vulnerability, Brad Udall

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

Presenter: Brad Udall, Western Water Assessment.

66 slides.

Damage Localization In Ambient Vibration By Constructing Proportional Flexibility Matrix, Zhongdong Duan, Guirong Yan, Jinping Ou, B. F. Spencer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Damage Localization Approaches based on Changes of Flexibilities Constitute an Important Technique for Damage Detection. However, the Unavailability of Flexibility Matrix with Output-Only Data Makes Flexibility-Based Approaches Not Really Applicable in the Very Important Cases of Ambient Vibrations. an Algorithm is Presented to Construct a Proportional Flexibility Matrix (PFM) from a Set of Arbitrarily Scaled Tested Modal Shapes and Modal Frequencies. the Constructed PFM is Just within a Scalar Multiplier to the Real Flexibility Matrix, and the Scalar Multiplier is Theoretically the First Modal Mass, Which is Undetermined Before the Mode is Properly Scaled. Instead of Real Flexibilities, the PFMs …

Observations At The Tidal Plume Front Of A High-Volume River Outflow, Philip M. Orton, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

We present shipboard observations of very strong convergence, vertical velocities and mixing, and near-bed impacts associated with the leading-edge front of the tidally-pulsed Columbia River plume. With upwelling-favorable winds and riverflow of 4900 m³s⁻¹, the plume propagates as a buoyant gravity current with a rotary, bore-like vertical frontal circulation and downwelling as strong as 0.35 m s⁻¹. In waters as deep as 65 m, near-bed currents intensify to as much as 1.0 m s⁻¹ after frontal passage, and are often associated with elevated acoustic backscatter. Mixing is locally strong, with an eddy diffusivity …

Laurance Lake Temperature Model, Chris Berger, Scott A. Wells, Robert Leslie Annear

Civil and Environmental Engineering Faculty Publications and Presentations

Laurance Lake is a reservoir located in Hood River County, Oregon (Figure 1). It is located at the base on Mt. Hood in Oregon (see Figure 2 and Figure 3), discharges into the Middle Fork of the Hood River. The reservoir was constructed in 1968 for irrigation storage and has a capacity 3564 acre- feet at full pool. Since the river vio lates temperature standards, this study has been designed to construct a hydrodynamic and temperature model of Laurance reservoir in order to assess strategies for improving temperatures in the Middle Fork River.

The objectives of the study are then …

Cost Comparison Of Existing Coatings For A Hypervelocity Test Rail, Mark A. Blomer

Theses and Dissertations

This study compared the relative costs, to the Department of Defense, of two different coatings used to protect a high speed test rail. Each coating was compared to the case of an uncoated rail with test conditions that caused catastrophic failure just after the test sled reached its maximum velocity. The total cost was finalized on a per test basis in order to sum cost of various expenditures that may only happen once every few tests. To compare the protective properties of each coating, various coated and uncoated samples were tested via a cylinder specimen Taylor Impact Test. Each coating's …

Bearing Capacity Analysis And Design Of Highway Base Materials Reinforced With Geofabrics, Tommy C. Hopkins, Liecheng Sun, Mikhail E. Slepak

Kentucky Transportation Center Research Report

The primary objective of this study was to develop and implement mathematical bearing capacity models originally proposed by Hopkins (1988, 1991) and Slepak and Hopkins (1993; 1995). These advanced models, which are based on limit equilibrium and are operated together, can be used to analyze the bearing capacity, or stability, of early construction of loads on a single layer of material, two-layered problems involving a layer of base aggregate and subgrade, and a foundation involving multiple layers of different materials, such as a flexible asphalt pavement. A Prandlt-type shear surface is used in the model analyses of layered foundations. In …

Roaded Catchments To Improve Reliability Of Farm Dams, David Stanton

Bulletins 4000 -

Maintaining reliable on-farm water supplies is an on-going challenge for landholders throughout Western Australia. Improving reliability of dams by constructing a roaded catchment is one of the most cost-effective methods of improving the performance and reliability of a farm water supply.

A roaded catchment is a water-harvesting structure designed to increase the amount of run-off from the catchment above a dam. The 'roads' of a roaded catchment are parallel ridges of earth with batters (or side slopes) that cause run-off to be directed into troughs or channels. The surface is lined with clay and compacted to make it smooth and …

Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi

Dissertations

Prediction of landfill gas generation and settlements are of concerns in design and maintenance of biocell landfills. Accurate settlement prediction is essential for design of piping systems used for the delivery of re-circulated leachate and recovery of landfill gas. Landfill settlement is the result of change in overburden stresses and biodegradation of waste. Biodegradation-induced settlement results from the re-arrangement of waste skeleton in response to the decomposition of waste mass.

Current practice of landfill settlement modeling is predominantly empirical, thus most of the available techniques make no attempt to simulate the real mechanisms of waste settlement. Traditionally compressibility index is …

Utility Of Remote Sensing Data In Retrieval Of Water Quality Consituents Concentrations In Coastal Water Of New Jersey, Ting Yu

Dissertations

Three important optical properties used for monitoring coastal water quality are the concentrations of chlorophyll (CHL), color dissolved organic matter (CDOM) and total suspended materials (TSM). Ocean color remote sensing, a technique to collect color data by detection of upward radiance from a distance (Bukata et al.,1995), provides a synoptic view for determining these concentrations from upwelling radiances. In the open ocean (Case-I), it is not difficult to derive empirical algorithms relating the received radiances to surface concentrations of water quality parameters. In coastal waters (Case-Il), there are serious unresolved problems in extracting chlorophyll concentration because of high concentration of …

Stormwater Utility Fees: Considerations & Options For Interlocal Stormwater Working Group (Iswg), New England Environmental Finance Center

Water

Stormwater utilities are a concept whose time seems to have arrived. Established by relatively few communities in the 1970s as a method of funding flood control measures, stormwater utilities now exist in over 400 municipalities and counties throughout the United States. During the next 10 years, their numbers are expected to swell dramatically – by one estimate to over 2,000 by the year 2014.

The reasons for this growth are multifold. Federal stormwater regulations passed in the 1980s (Phase I of the National Pollutant Discharge Elimination System Program, or NPDES), motivated many larger communities to seek alternative funding sources and …

Inside Unlv, Erin O'Donnell, Diane Russell, Carol C. Harter

Inside UNLV

No abstract provided.

Uncertainty Assessment Of Hydrologic Model States And Parameters: Sequential Data Assimilation Using The Particle Filter, Hamid Moradkhani, Kuo-Lin Hsu, Hoshin V. Gupta, Soroosh Sorooshian

Civil and Environmental Engineering Faculty Publications and Presentations

Two elementary issues in contemporary Earth system science and engineering are (1) the specification of model parameter values which characterize a system and (2) the estimation of state variables which express the system dynamic. This paper explores a novel sequential hydrologic data assimilation approach for estimating model parameters and state variables using particle filters (PFs). PFs have their origin in Bayesian estimation. Methods for batch calibration, despite major recent advances, appear to lack the flexibility required to treat uncertainties in the current system as new information is received. Methods based on sequential Bayesian estimation seem better able to take advantage …

Sensitivity And Uncertainty Analysis Coupled With Automatic Calibration For A Distributed Watershed Model, Misgana K. Muleta, John W. Nicklow

Civil and Environmental Engineering

Distributed watershed models should pass through a careful calibration procedure before they are utilized as a decision making aid in the planning and management of water resources. Although manual approaches are still frequently used for calibration, they are tedious, time consuming, and require experienced personnel. This paper describes an automatic approach for calibrating daily streamflow and daily sediment concentration values estimated by the US Department of Agriculture’s distributed watershed simulation model, Soil and Water Assessment Tool (SWAT). The automatic calibration methodology applies a hierarchy of three techniques, namely screening, parameterization, and parameter sensitivity analysis, at the parameter identification stage of …

Time Domain Characterization Of 1-2 Ghz Circular-Ended Bowtie Antenna Using Normalizad Impulse Response, Joko Suryana, Andriyan B. Suksmono, Tati R. Mengko

Makara Journal of Technology

Time Domain Characterization of 1-2 GHz Circular-ended Bowtie Antenna Using Normalizad Impulse Response. Frequency domain analysis is a powerful and compact tool for characterizing the antenna parameters such as gain, radiation pattern and the impedance as a function of frequency. However, if time or space is a major concern, such as in the GPR appication, the time domain analysis would be a very important tool due to their unique capability for determining the echo delay and range profile of target image. In this paper, we will describe the classical theory of system characterization in time domain, and then also propose …

Bs News

Building Services Engineering

No abstract provided.

A Water Station Model With Fuzzy C-Means Algorithm To Promote The Ability Of Water Distribution Systems, Hong-Min Shau, Wen-Chih Huang, Bi-Liang Lin, Jui-Min Hsiao

Journal of Marine Science and Technology–Taiwan

A water station model will simulate the performance of a water distribution system for a given station location and quantity patterns in order to analyze present population distribution in the overall region, establish a reasonable local sample for each district network and obtain the optimal solution of the water supply stations. To establish a local sample, this model uses the Fuzzy C-Means algorithm (FCM algorithm) of the fuzzy clustering method. The sites have been modified with the mobile method so that the group points can be located at places nearest to the roadside in order to achieve the minimum cost. …

Development Of Multiple Growth Strategies For Use In Developing Traffic Forecasts: A Robustness Approach, Deogratias Eustace, Eugene R. Russell, E. Dean Landman

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Decisions that may be based on misleading forecasts may lead to a misallocation of funds and to under-performing projects during construction and operation. Poor projections of demographic and socioeconomic data are usually cited as the major source of poor traffic assignment projections and hence, unfavorably conceived planning and construction of street and highway infrastructure facilities.

This report evaluated the accuracy of long range projections by using a transportation study done the in 1970s, projecting transportation demand 20 years into the future. The projected travel model inputs were compared with what actually happened after the horizon year had been reached and …

Estimating Performance Time For Air Force Military Construction Projects, Greg J. Hoffman

Theses and Dissertations

The prediction of construction time performance is a problem of interest to both researchers and construction industry practitioners. This research seeks to identify significant factors which may influence construction durations for Air Force Military Construction (MILCON) projects to establish a time prediction model. Data were collected for 856 MILCON projects completed between 1988 and 2004; this included both traditional facility and non-facility (e.g. airfield pavements, utilities) projects. These data were analyzed using Bromilow's time-cost (BTC) model (1969) as well as multiple linear regression. Neither model produced acceptable results for non-facility projects; however, the multiple linear regression model was found to …

Modeling Application Of Hydrogen Release Compound To Effect In Situ Bioremediation Of Chlorinated Solvent-Contaminated Groundwater, Ryan C. Wood

Theses and Dissertations

This study investigates how application of Hydrogen Release Compound (HRC) might be implemented to remediate a site contaminated with tetrachloroethene (PCE) or its daughter products, under varying site conditions. The 3-D reactive transport model RT3D was coupled with a dual-Monod biodegradation submodel to simulate the effect of the hydrogen generated by HRC on accelerating the biodegradation of dissolved chlorinated solvents. Varying site conditions and injection well configurations were investigated to determine the effect of these environmental and design conditions on overall treatment efficiency. The model was applied to data obtained at a chlorinated solvent contaminated site at Vandenberg AFB, where …

An Investigation Into Palladium-Catalyzed Reduction Of Perchlorate In Water, Eric G. Barney

Theses and Dissertations

In this study, application of a catalytic reactor to facilitate chemical reduction of perchlorate was investigated. Palladium-coated pellets were used as the catalyst, and formic acid was used as the reductant. Reactor performance was evaluated under a variety of operating conditions (influent pH, reductant concentration, residence time). Very little perchlorate reduction was observed under any operating condition. At best, approximately 8% perchlorate reduction was observed. This small reduction efficiency is clearly not sufficient for environmental treatment applications. Perchlorate strongly adsorbed to the catalyst at low pH (3 - 3.3). At higher pH (4 - 10), little adsorption was observed. This …

Validation Of An Innovative Groundwater Contaminant Flux Measurement Method, Seh J. Kim

Theses and Dissertations

The ability to measure groundwater contaminant flux is increasingly being recognized as crucial in order to prioritize contaminated site cleanups, estimate the efficiency of remediation technologies, measure rates of natural attenuation, and apply proper source terms to model groundwater contaminant transport. An innovative mass flux measurement method using horizontal flow treatment wells (HFTWs) was developed recently to compensate for the disadvantages of other flux measurement methods that are being used. Flux measurement methods can be categorized as either point methods or integral methods. As the name suggests, point methods measure flux at a specific point or points in the subsurface. …

Site Assessments, Martyn Keen

Natural resources published reports

The processes of collecting and recording site data as part of the preliminary tasks leading to a landscape or project design.

This standard applies to landscape and project designs for catchments of any size. Designs include: the installation of conservation earthworks; revegetation; land use planning; or implementation of erosion and sediment control practices. The design may also include any combination of the above

Roaded Catchments, Martyn Keen

Natural resources published reports

A roaded catchment is one of the water harvesting structures known collectively as improved catchments. It has a broad 'V' shaped cross section and a surface cover of clay. It is used to increase run-off yield and divert water to farm dams.

Multi-Criteria Decision Analysis For The Optimal Management Of Nitrate Contamination Of Aquifers, Mohammad N. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

We present an integrated methodology for the optimal management of nitrate contamination of ground water combining environmental assessment and economic cost evaluation through multi-criteria decision analysis. The proposed methodology incorporates an integrated physical modeling framework accounting for on-ground nitrogen loading and losses, soil nitrogen dynamics, and fate and transport of nitrate in ground water to compute the sustainable on-ground nitrogen loading such that the maximum contaminant level is not violated. A number of protection alternatives to stipulate the predicted sustainable on-ground nitrogen loading are evaluated using the decision analysis that employs the importance order of criteria approach for ranking and …

Modeling Groundwater Flow And Contaminant Transporting Fractured Aquifers, Jason M. Bordas

Theses and Dissertations

The hybrid discrete fracture network/equivalent porous medium (DFN/EPM) model was selected for analysis and application to simulate a contaminated site in this study. The DFN/EPM was selected because it appeared to have the potential to aid decision making by remedial project managers at contaminated DoD fractured aquifer sites. This model can use data that are typically available at a site while incorporating the important processes relevant to describing contaminant transport in a fractured medium. The model was applied to simulate the operation of a pump-and-treat remedial action at a trichloroethene-contaminated fractured aquifer at Pease AFB. The model was able to …

Using Value-Focused Thinking To Evaluate The Practicality Of Ground-Source Heat Pumps At Military Installations, Jimmy J. Jeoun

Theses and Dissertations

Because of potential cost and energy savings, military decision-makers may want to consider the use of energy-efficient heating, ventilating, and air-conditioning (HVAC) systems at their installations. Ground source heat pumps (GSHPs), in particular, show great promise because of their low energy requirements and low life-cycle costs. However, there currently exists no design guidance or established criteria for HVAC selection. Consequently, military decision-makers have no basis for comparing conventional HVAC systems and GSHPs. The Value-Focused Thinking (VFT) methodology was used to create a multi-objective decision analysis model that measures the value of different HVAC systems. Consisting of five bottom-tier values and …

Kentucky Geotechnical Database, Tommy C. Hopkins, Tony L. Beckham, Liecheng Sun, Bill Pfalzer

Kentucky Transportation Center Research Report

Development of a comprehensive dynamic, geotechnical database is described. Computer software selected to program the client/server application in windows’ environment, components and structure of the geotechnical database, and primary factors considered in constructing the database are discussed. Oracle ®8i, PowerBuilder ®8, and Map Object ® software were used to construct the database, build graphical user interfaces (GUI), and embed roadway maps, respectively. Any number of users may use the database simultaneously. Twelve highway district offices and several central offices of the Kentucky Transportation Cabinet are connected to the database. Data may be entered and retrieved dynamically in the client/server structure. …

Excavated Tanks And Hillside Dams, Martyn Keen

Natural resources published reports

An excavated tank is an earth structure on near level land used to impound water, in which a percentage of the storage capacity is below ground level. It includes similar structures constructed on sloping land, referred to as 'hillside dams'. These are specific types of the group of water-impounding structures known as 'farm dams'.

Probabilistic Modeling Of One Dimensional Water Movement And Leaching From Highway Embankments Containing Secondary Materials, Defne S. Apul, Kevin H. Gardner, T. Taylor Eighmy, Ernst Linder, Tara Frizzell, Ruth Roberson

Civil & Environmental Engineering

Predictive methods for contaminant release from virgin and secondary road construction materials are important for evaluating potential long-term soil and groundwater contamination from highways. The objective of this research was to describe the field hydrology in a highway embankment and to investigate leaching under unsaturated conditions by use of a contaminant fate and transport model. The HYDRUS2D code was used to solve the Richards equation and the advection–dispersion equation with retardation. Water flow in a Minnesota highway embankment was successfully modeled in one dimension for several rain events after Bayesian calibration of the hydraulic parameters against water content data at …

Corrosion Studies On Alpha Tantalum And Beta Tantalum Coated Steel, Sung Min Maeng

Dissertations

Tantalum coating by sputtering, one form of physical vapor deposition (PVD), has been investigated as a replacement for chromium coatings on gun bores to protect them from erosion and corrosion due to its high ductility and high corrosion resistance in aggressive environments. When deposited as a film on steel substrates by sputtering, either α-Ta, β-Ta, or a mixture of both phases have been observed under varying deposition conditions. To evaluate corrosion behavior of Ta coatings, electrochemical impedance spectroscopy and potentiodynamic polarization were conducted as a function of coating thickness. The coating porosity was observed to decrease with increasing coating thickness …