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2015

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Articles 331 - 360 of 1146

Full-Text Articles in Civil and Environmental Engineering

A New Method For Simulating Power Flow Density Focused By A Silicon Lens Antenna Irradiated With Linearly Polarized Thz Wave, Catur Apriono, Eko Tjipto Rahardjo, Norihisa Hiromoto Aug 2015

A New Method For Simulating Power Flow Density Focused By A Silicon Lens Antenna Irradiated With Linearly Polarized Thz Wave, Catur Apriono, Eko Tjipto Rahardjo, Norihisa Hiromoto

Makara Journal of Technology

A terahertz system uses dielectric lens antennas for focusing and collimating beams of terahertz wave radiation. Linearly polarized terahertz wave radiation has been widely applied in the terahertz system. Therefore, an accurate method for analyzing the power flow density in the dielectric lens antenna irradiated with the linearly polarized terahertz wave radiation is important to design the terahertz systems. In optics, ray-tracing method has been used to calculate the power flow density by a number density of rays. In this study, we propose a method of ray-tracing combined with Fresnel’s transmission, including transmittance and polarization of the terahertz wave radiation …


Stochastic Optimization Of Supply Chain Risk Measures –A Methodology For Improving Supply Security Of Subsidized Fuel Oil In Indonesia, Adinda Yuanita, Andi Noorsaman Sommeng, Anondho Wijonarko Aug 2015

Stochastic Optimization Of Supply Chain Risk Measures –A Methodology For Improving Supply Security Of Subsidized Fuel Oil In Indonesia, Adinda Yuanita, Andi Noorsaman Sommeng, Anondho Wijonarko

Makara Journal of Technology

Monte Carlo simulation-based methods for stochastic optimization of risk measures is required to solve complex problems in supply security of subsidized fuel oil in Indonesia. In order to overcome constraints in distribution of subsidized fuel in Indonesia, which has the fourth largest population in the world—more than 250,000,000 people with 66.5% of productive population, and has more than 17,000 islands with its population centered around the nation's capital only—it is necessary to have a measurable and integrated risk analysis with monitoring system for the purpose of supply security of subsidized fuel. In consideration of this complex issue, uncertainty and probability …


Thermodynamic Analysis Of Irreversible Heat-Transformers, Niccolo` Giannetti, Arnas Arnas, Andrea Rocchetti, Kiyoshi Saito Aug 2015

Thermodynamic Analysis Of Irreversible Heat-Transformers, Niccolo` Giannetti, Arnas Arnas, Andrea Rocchetti, Kiyoshi Saito

Makara Journal of Technology

Absorption heat transformers extend the possibilities for efficient and environment-friendly energy conversion processes. Based on a general thermodynamic model of three-thermal cycles with finite thermal capacity of the heat sources, this paper is intent upon analyzing and optimizing the performance of absorption heat transformers, by including the influence of irreversibility in the analytical expression of the system efficiency. Dimensionless parameters for an overall optimization are defined and a first screening is performed to clarify their influence. Dependence on the main factors is highlighted to suggest how to change them in order to enhance the whole system performance. Under this point …


Strain Distribution And Crack Detection In Concrete Overlays With Pulse Pre-Pump Brillouin Optical Time Domain Analysis, Yi Bao, Genda Chen Aug 2015

Strain Distribution And Crack Detection In Concrete Overlays With Pulse Pre-Pump Brillouin Optical Time Domain Analysis, Yi Bao, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report is focused on the measurement of strain distributions and crack detection in unbonded and bonded pavement overlays. The main objectives of this study are: (a) to characterize the strain sensing properties of distributed fiber optic sensors with recently developed pulse pre-pump Brillouin optical time domain analysis (PPP-BOTDA), (b) to develop an installation method for real world applications, (c) to document the performance of the PPP-BOTDA technology in unbonded/bonded pavement applications, and (d) to develop a numerical model to facilitate the analysis of mechanical behavior of unbonded pavement overlay under vehicle wheel loads. A thin concrete layer can be …


Geotechnical Laboratory Characterization Of Sand-Zeolite Mixtures., Hong Shang, Aug 2015

Geotechnical Laboratory Characterization Of Sand-Zeolite Mixtures., Hong Shang,

Electronic Theses and Dissertations

Zeolite and sand mixture is an ideal reactive filling material for the Permeable Reactive barrier (PRB) due to its higher hydraulic conductivity and sorption capacity. This study applied three ASTM standard tests to examine the geotechnical engineering properties of ASTM 20-30 sand and zeolite (clinoptilolite) mixtures with varying zeolite mass percentages (25%, 50%and 75%). Conducted lab tests including: Proctor compaction, hydraulic conductivity in rigid wall permeameter and one-dimensional consolidation. The goals of this study were to quantify the impact of zeolite content and compactive effort on the density, conduction and compressibility of the sand-zeolite mixtures.


Macro Model For Solid And Perforated Masonry Infill Shear Walls., Farid Nemati Aug 2015

Macro Model For Solid And Perforated Masonry Infill Shear Walls., Farid Nemati

Electronic Theses and Dissertations

In this dissertation the performance of masonry walls enclosed by frame structures is studied and a new finite element model for these systems is presented. As part of this effort, the common modeling approaches i.e. micro-models and macro-models are briefly reviewed and their specifications are compared. Based on the findings in these comparisons, it was shown that macro modeling is the preferred modeling approach and the development of the new model is presented. The proposed model is described in detail and the calibration procedures along with the material models, used in the proposed model, are presented. To account for the …


Performing A Steady-State Seepage Analysis Using Seep/W : A Primer For Engineering Students., Matthew R. Broaddus Aug 2015

Performing A Steady-State Seepage Analysis Using Seep/W : A Primer For Engineering Students., Matthew R. Broaddus

Electronic Theses and Dissertations

This thesis is comprised of five independent modules that were developed to provide a primer to understanding groundwater seepage. These modules serve as the template to conduct steady-state seepage analyses through embankments utilizing SEEP/W, a finite element seepage modeling program. Module 1 and 2 are more theoretical in nature to provide the background knowledge necessary to conduct a steady-state seepage analysis, while Modules 3, 4, and 5 focus more on the application of seepage models and how they can be used to solve various groundwater seepage problems. Supplementary material, including PowerPoint presentations, handouts, and a manual on how to utilize …


Accumulation Of Gas-Phase Methamphetamine On Clothing, Toy Fabrics, And Skin Oil, G. Morrison, N. V. Shakila, K. Parker Aug 2015

Accumulation Of Gas-Phase Methamphetamine On Clothing, Toy Fabrics, And Skin Oil, G. Morrison, N. V. Shakila, K. Parker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To better understand methamphetamine exposure and risk for occupants of former residential clandestine methamphetamine laboratories, we measured the dynamic accumulation of methamphetamine in skin oil, cotton and polyester (PE) clothing, upholstery, and toy fabric (substrates) exposed to 15-30 ppb (91-183 μg/m3) neutral methamphetamine in air for up to 60 days. The average equilibrium partition coefficients at 30% RH, in units of μg of methamphetamine per gram of substrate per ppb, are 3.0 ± 0.2 for a PE baby blanket, 5.6 ± 3.5 for a PE fabric toy, 3.7 ± 0.2 for a PE shirt, 18.3 ± 8.0 for a PE/cotton …


Effect Of Thermal Loads On Substructures: New Trammel Creek Bridge On Ky-100 In Allen County, Kentucky, Zhihui Zhu, Michael T. Davidson, Issam E. Harik, Charlie Sun Aug 2015

Effect Of Thermal Loads On Substructures: New Trammel Creek Bridge On Ky-100 In Allen County, Kentucky, Zhihui Zhu, Michael T. Davidson, Issam E. Harik, Charlie Sun

Kentucky Transportation Center Research Report

When infrastructure is subjected to temperature changes, structural members that are either partially or fully restrained against motion can develop internal stresses. The phenomenon of temperature-induced internal stress development in superstructure members has prompted the American Association of State Highway and Transportation Officials (AASHTO) to include provisions for determining superstructure temperature load effects. However, little consideration has been given to explicitly quantifying the effect that thermal stresses have on foundation systems such as intermediate bridge piers. The objective of this study is to instrument a multi-span integral abutment bridge with temperature and bridge response monitoring devices, and ultimately, to make …


2015 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green, Michael A. Fields Aug 2015

2015 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green, Michael A. Fields

Kentucky Transportation Center Research Report

The objective of the survey summarized in this report was to establish a statewide safety belt usage rate in Kentucky for 2015. This rate can be compared to those determined from previous surveys. The 2015 statewide survey documents the continued increase in usage associated with the change in the law to allow primary enforcement and related education and enforcement.


Evaluation Of The Safety Effectiveness Of Clearview Font And Fluorescent Yellow Sheeting On Michigan Freeways And Non-Freeways, Lusanni Mercedes Acosta Rodrieuez Aug 2015

Evaluation Of The Safety Effectiveness Of Clearview Font And Fluorescent Yellow Sheeting On Michigan Freeways And Non-Freeways, Lusanni Mercedes Acosta Rodrieuez

Masters Theses

Halation or irradiation makes guide sign fonts difficult to read. Missing the necessary guide sign information causes anxiety and confusion to drivers, and hence may lead to crashes. In order to avoid or mitigate the situation a newer font, Clearview, is used to provide better readability at long distances. In a similar context the lack of brightness in sheeting material for warning signs reduces conspicuity of sings. Installation of fluorescent yellow sheeting has been done to provide signs with more noticeable and brighter materials. This observational before and after study is an evaluation of the safety and economic benefits of …


Spatial Database For Intersections, Eric R. Green, Christopher L. Blackden, Michael A. Fields Aug 2015

Spatial Database For Intersections, Eric R. Green, Christopher L. Blackden, Michael A. Fields

Kentucky Transportation Center Research Report

Deciding which intersections in the state of Kentucky warrant safety improvements requires a comprehensive inventory with information on every intersection in the public roadway network. The Kentucky Transportation Cabinet (KYTC) had previously catalogued only those intersections where state-maintained roadways met. However, this inventory did not account for intersections between state- and locally-maintained routes, nor was it designed to accommodate regular updates. As such, the Kentucky Transportation Center (KTC) at the University of Kentucky developed a methodology to create and maintain a full inventory of every intersection in the state. The database contains precise location information as well as several safety …


Synthesis Of Public-Private Partnerships: Potential Issues And Best Practices For Program And Project Implementation And Administration, Bryan Gibson, Candice Y. Wallace, Roy E. Sturgill Aug 2015

Synthesis Of Public-Private Partnerships: Potential Issues And Best Practices For Program And Project Implementation And Administration, Bryan Gibson, Candice Y. Wallace, Roy E. Sturgill

Kentucky Transportation Center Research Report

Public-private partnerships (P3s or PPPs) offer an innovative procurement method for the public sector. P3s involve collaborations between the public and private sectors to finance, develop or maintain transportation infrastructure. In an era of shrinking budgets and increased demand for transportation infrastructure, the Kentucky Transportation Cabinet (KYTC) can analyze experiences in other states to determine a best path forward on the issue of P3s. The objective of this study is to examine benefits and drawbacks of using P3s, current trends and past performance of P3s in the procurement of state transportation infrastructure projects, and common legislative statutes relating to P3s. …


Multi-Component Active Source Rayleigh Wave Analysis, Gabriel Gribler Aug 2015

Multi-Component Active Source Rayleigh Wave Analysis, Gabriel Gribler

Boise State University Theses and Dissertations

Determining how a building site will respond to earthquake ground shaking plays a critical role in proper construction practices. One critical constraint on how a site responds is the near surface shear wave seismic velocity distribution. One commonly used method for indirectly estimating shear wave velocities is Multichannel Analysis of Surface Waves (MASW), which utilizes a spread of vertical geophones to measure Rayleigh wave dispersion. With this approach, phase velocity vs. frequency dispersion curve picks can be used to estimate shear wave velocities with depth. I investigate the use of two (vertical and horizontal inline) component seismic signals to record …


Fluoride And Phosphate Removal From Industrial And Domestic Wastewaters Using Cerium Chloride, John Michael Gonzales Aug 2015

Fluoride And Phosphate Removal From Industrial And Domestic Wastewaters Using Cerium Chloride, John Michael Gonzales

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of cerium chloride (CeCl3) to remove fluoride and phosphate from waters is addressed in this study. High concentrations of fluoride exist in groundwater especially in developing countries. Consumption drinking water containing high levels of fluoride can lead to serious cases of dental and skeletal fluorosis. Current defluoridation technologies are limited, especially for high levels of fluoride, and are expensive. Industrial wastewaters contribute to the highest fluoride contamination in the world. With the increasing production of electronic materials, the global fluoride concentration and fluoride-contaminated waters have grown tremendously. Excessive discharge of phosphate into the environment promotes eutrophication of lakes …


Development Of A Decision Support Framework For The Planning Of Sustainable Transportation Systems, Pankaj Maheshwari Aug 2015

Development Of A Decision Support Framework For The Planning Of Sustainable Transportation Systems, Pankaj Maheshwari

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the rapid increase in economic development throughout the world, there is stress on the resources used to support global economy, including petroleum, coal, silver, and water. Currently, the world is consuming energy at an unprecedented rate never seen before. The finite nature of such non-renewable natural resources as petroleum and coal puts pressure on the environmental system, and ultimately reduces the availability of resources for future generations. Hence, it is critical to develop planning and operational strategies that seek to achieve a sustainable use of existing natural resources.

With this motivation, this dissertation focuses to develop a decision support …


Geotechnical Surrogates For Sediment Shear Behavior In Southern Nevada, Rinu Ann Samuel Aug 2015

Geotechnical Surrogates For Sediment Shear Behavior In Southern Nevada, Rinu Ann Samuel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Nevada Department of Transportation design standards for deep foundations, particularly drilled shafts, in the Las Vegas Valley (LVV) may be overly conservative due to the challenges in characterizing strong but difficult-to-sample sediment strata, such as dense gravel, heavily cemented sediments, and mixed materials, which occur commonly in the LVV. Consequently, there is a need for investigating methods to assess the shear behavior of sediments that occur in the LVV in situ in working ranges of stress/strain, with the end goal of improving abilities to predict the capacity of drilled shafts in the LVV. To this end, global correlations of …


Quantification Of Variable Rate Irrigation Benefits And Spatial Variability In Root Zone Water Holding Capacity, Tsz Him Lo Aug 2015

Quantification Of Variable Rate Irrigation Benefits And Spatial Variability In Root Zone Water Holding Capacity, Tsz Him Lo

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Variable rate irrigation (VRI) investment decisions require field-specific knowledge of benefits. The objective of this research was to help producers and consultants consider and quantify potential benefits of VRI. First, a conceptual model was developed for evaluating the public and/or private gain from adopting VRI where irrigation water supply is non-restrictive. Potential benefits were classified into three categories and were attributed to ten reasons. In the Central Plains at current prices, a small improvement in corn (maize) yield would make a large contribution to VRI profitability. Second, the potential irrigation withdrawal reduction from adapting VRI to spatial heterogeneity of root …


Evaluate Students’ Learning Effectiveness Of Hvac System Using 3d Game Animation, Lalitha Devi Nandam Aug 2015

Evaluate Students’ Learning Effectiveness Of Hvac System Using 3d Game Animation, Lalitha Devi Nandam

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

An important skill required for students in Construction Engineering and Architecture is to understand what the major components are and how the whole system and its components function. Students typically learn to understand HVAC equipment by reviewing two-dimensional (2D) CAD drawings, images and site visits. With latest developments in 3D game engines for facilitating interactive learning, it is now possible for students to experience three-dimensional (3D) environments of HVAC systems. While this technology is still at an early stage in learning application, it has the potential to significantly enhance the capability of students to study, comprehend and gain experience designing …


Evaluating The Security Of Smart Home Hubs, Steven A. Christiaens Aug 2015

Evaluating The Security Of Smart Home Hubs, Steven A. Christiaens

Theses and Dissertations

The goal of this research is to improve the security of smart home hubs by developing a standard against which hubs can be evaluated. This was done by first reviewing existing standards, guides, and collections of best practices. I determined that adapting or extending an existing standard was the best way to proceed. Potential candidates were selected, and after thorough comparison, I chose to extend the OWASP Application Security Verification Standard (ASVS). Extensions were composed of additional security requirements to address smart home hub functionality not covered by the existing requirements of the ASVS. These additional requirements were developed based …


Dynamic Characteristics And Seismic Response Analysis Of A Long-Span Steel-Box Basket-Handle Railway Arch Bridge, Xuhui He, Biao Wei, Yunfeng Zou, Dongyang Hu, Daniel G. Linzell Aug 2015

Dynamic Characteristics And Seismic Response Analysis Of A Long-Span Steel-Box Basket-Handle Railway Arch Bridge, Xuhui He, Biao Wei, Yunfeng Zou, Dongyang Hu, Daniel G. Linzell

Department of Civil and Environmental Engineering: Faculty Publications

The inside oblique angle between the vertical plane and the arch rib has been shown to be one of the main factors influencing dynamic properties of long-span steel-box basket-handle arch bridges. Details related to the extent, that the inside oblique angle influenced the dynamic characteristics and the seismic response of the arch bridge under the combined longitudinal and vertical seismic excitation and under the combined lateral and vertical seismic excitation, were reported herein. Four oblique angles (0°, 3°, 4.8°, and 6°) were selected based on the arch ribs height and bridge deck width. Findings suggested that a larger inside oblique …


Estimation Of Historic Flows And Sediment Loads To San Francisco Bay, 1849 – 2011, Hamed Moftakhari Rostamkhani, David A. Jay, Stefan A. Talke, David H. Schoellhamer Aug 2015

Estimation Of Historic Flows And Sediment Loads To San Francisco Bay, 1849 – 2011, Hamed Moftakhari Rostamkhani, David A. Jay, Stefan A. Talke, David H. Schoellhamer

Civil and Environmental Engineering Faculty Publications and Presentations

River flow and sediment transport in estuaries influence morphological development over decadal and century time scales, but hydrological and sedimentological records are typically too short to adequately characterize long-term trends. In this study, we recover archival records and apply a rating curve approach to develop the first instrumental estimates of daily delta inflow and sediment loads to San Francisco Bay (1849 – 1929). The total sediment load is constrained using sedimentation/erosion estimated from bathymetric survey data to produce continuous daily sediment transport estimates from 1849 to 1955, the time period prior to sediment load measurements. We estimate that ~55% (45 …


Evaluating The Use Of Crowdsourcing As A Data Collection Method For Bicycle Performance Measures And Identification Of Facility Improvement Needs, Miguel A. Figliozzi, Bryan Philip Blanc Aug 2015

Evaluating The Use Of Crowdsourcing As A Data Collection Method For Bicycle Performance Measures And Identification Of Facility Improvement Needs, Miguel A. Figliozzi, Bryan Philip Blanc

Civil and Environmental Engineering Faculty Publications and Presentations

This research developed a smartphone application called ORcycle to collect cyclists’ routes, users, and comfort levels. ORcycle combines GPS revealed route data collection with new questionnaires that try to elicit cyclists’ attitudes as well as comfort levels and factors that influence their perceived comfort and route choice. The new questionnaires were developed to better understand how cyclists’ comfort levels are affected by route characteristics, route stressors, safety reports, cyclists’ demographics, and cyclists’ cycling attitude. Preliminary results show that many trip characteristics, route choice factors, route stressors and demographic variables are correlated with comfort levels. ORcycle is the first statewide deployment …


Improved Safety Performance Functions For Signalized Intersections, Karen Dixon, Christopher Monsere, Raul Avelar, Joel Stephen Barnett, Paty Escobar, Sirisha Murthy Kothuri Aug 2015

Improved Safety Performance Functions For Signalized Intersections, Karen Dixon, Christopher Monsere, Raul Avelar, Joel Stephen Barnett, Paty Escobar, Sirisha Murthy Kothuri

Civil and Environmental Engineering Faculty Publications and Presentations

For this effort, the research team developed new safety performance functions (SPFs) for signalized intersections in Oregon. The modeling dataset consisted of 964 crashes from a total of 73 intersections that were randomly selected based on the presence of a traffic signal (identified through the crash data records). The SPFs were developed using a Poissonlognormal Generalized Linear Mixed model framework for total crashes and severe injury crashes (coded as KAB). Three SPFs were developed: 1) an SPF for total crashes, which relies on both major and minor AADTs to predict the expected number of crashes; 2) an SPF for KAB …


Agricultural Water Management In The Sevier River Basin, Utah: A Multidisciplinary Approach, Daeha Kim Aug 2015

Agricultural Water Management In The Sevier River Basin, Utah: A Multidisciplinary Approach, Daeha Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Sevier River Basin situated in south central Utah is characterized by its semiarid climate, snowmelt-driven runoff, and high dependency on agricultural economy. High evapotranspiration and low precipitation make agricultural production challenging, but naturally stored water in the snowpack in the mountains alleviates water stresses during high water demand seasons. The snowmelt-driven river flow along the main channel is highly exploited for irrigation for farms near the Sevier River. Reservoir operations and river diversions result in heavily regulated flows from the upper to the lower basins. The return flows of over-irrigated water in the upper basin increase salinity of surface …


A Gis-Based Expert Systems Predictive Habitat Model For Threatened And Endangered Species: Case Study Using Kentucky Arrow Darter, Benjamin L. Blandford, Michael Shouse, John Ripy Aug 2015

A Gis-Based Expert Systems Predictive Habitat Model For Threatened And Endangered Species: Case Study Using Kentucky Arrow Darter, Benjamin L. Blandford, Michael Shouse, John Ripy

Kentucky Transportation Center Research Report

This study presents a GIS-based predictive habitat suitability model for the Kentucky arrow darter (Etheostoma spilotum), a fish species of the upper Kentucky River basin that is a candidate for federal listing by the U.S. Fish and Wildlife Service. The model is based on previous work: the development of a similar predictive model for identifying the habitat of the blackside dace, a threatened minnow species of the upper Cumberland River basin in Southeastern Kentucky. The research describes a weighted, rules-based system which incorporates expert knowledge about habitat preferences for the arrow darter. For this model, five habitat factors …


A Method For Using Pre-Computed Scenarios Of Physically-Based Spatially-Distributed Hydrologic Models In Flood Forecasting Systems, Herman Guillermo Dolder Aug 2015

A Method For Using Pre-Computed Scenarios Of Physically-Based Spatially-Distributed Hydrologic Models In Flood Forecasting Systems, Herman Guillermo Dolder

Theses and Dissertations

Every year floods are responsible of a significant number of human losses, many of which could be avoided with a broader implementation of flood forecasting systems. Nevertheless, there are still some technological and economic limitations that impede the creation of these systems in many parts of the world. At the core of many flood forecasting systems is a hydrologic model that transforms the weather forecast into a flow forecast. Using real-time modeling for potential floods poses a series of problems: if the model is complex, the computational power required can be significant, and consequently expensive, and if the model is …


Developed Pipe Bursting Specifications Using High Density Poly Ethylene (Hdpe), Manoj Mohanraj Jul 2015

Developed Pipe Bursting Specifications Using High Density Poly Ethylene (Hdpe), Manoj Mohanraj

Master of Technology Management Plan II Graduate Projects

Pipe bursting is a trenchless method for replacing old deteriorated or under sized pipe by fracturing or splitting. Earlier published pipe bursting specifications do not completely cover the current state of the art and without proper allocation of risks. Specifications are set of written instructions given by the owner to the contractor. The developed Pipe Bursting specification with HDPE will help the owners, contractor, and engineers to carry out a successful burst timely and economically. In this research study, sixteen specifications from various sources were collected. Various agreements and disagreements among these specifications were identified, analyzed, and considered while developing …


Land Use And Water And Soil Management Practices Impacts On Potential Groundwater Recharge In Loess Regions Of South Central Nebraska, Gustavo Bosch-Rubia Jul 2015

Land Use And Water And Soil Management Practices Impacts On Potential Groundwater Recharge In Loess Regions Of South Central Nebraska, Gustavo Bosch-Rubia

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Sustainability of agro-ecosystems must consider land use and water and soil management effects on groundwater recharge. Water flow beneath the plant root zone through the intermediate vadose zone determines potential groundwater recharge. Different land uses, water and soil management practices control deep percolation as a result of changes on evapotranspiration and infiltration. This study of the impact of surface activities on deep percolation was conducted at six locations across Nebraska: Two center-pivot irrigated no-till planting systems fields were compared with one tilled center-pivot irrigated field, a furrow irrigated field with multiple tillage treatments, an eco-fallow dryland farming system, and a …


A Multivariate Modeling Approach For Generating Ensemble Climatology Forcing For Hydrologic Applications, Sepideh Khajehei Jul 2015

A Multivariate Modeling Approach For Generating Ensemble Climatology Forcing For Hydrologic Applications, Sepideh Khajehei

Dissertations and Theses

Reliability and accuracy of the forcing data plays a vital role in the Hydrological Streamflow Prediction. Reliability of the forcing data leads to accurate predictions and ultimately reduction of uncertainty. Currently, Numerical Weather Prediction (NWP) models are developing ensemble forecasts for various temporal and spatial scales. However, it is proven that the raw products of the NWP models may be biased at the basin scale; unlike model grid scale, depending on the size of the catchment. Due to the large space-time variability of precipitation, bias-correcting the ensemble forecasts has proven to be a challenging task. In recent years, Ensemble Pre-Processing …