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Full-Text Articles in Civil and Environmental Engineering

Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe Aug 2014

Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe

Graduate Theses and Dissertations

A compacted clay liner (test pad) was constructed and instrumented with volumetric water content and soil matric potential sensors to determine soil water characteristic curves (SWCC) and hydraulic conductivity (k) functions. Specifically, the compacted clay liner was subjected to an infiltration cycle during a sealed double ring infiltrometer (SDRI) test followed by a drying cycle. After the drying cycle, Shelby tube samples were collected from the compacted clay liner and flexible wall permeability (FWP) tests were conducted on sub-samples to determine the saturated hydraulic conductivity. Moreover, two computer programs (RETC and UNSAT-H) were utilized to model the SWCCs and k-functions …


An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer Aug 2014

An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer

All Theses

Understanding how radionuclides interact in the subsurface is important for the remediation of contaminated sites, assessment of risk due to radioactive waste disposal, and designing new radioactive waste management strategies. The current understanding of the geochemical behavior of radionuclides in the subsurface and more specifically the vadose zone has been developed through reactive transport modeling supplemented by laboratory experiments. Interactions between radionuclides with the mineral particles and organic matter in the vadose zone can be very complex and while laboratory experiments produce valuable data, few controlled, intermediate scale transport studies have been performed. In order to accurately predict vadose zone …


Evaluation Of Earthquake Hazard For Las Vegas Valley, Nevada Incorporating Probabilistic Hazard Assessment And Non--Linear Site Response, Suchan Lamichhane Aug 2014

Evaluation Of Earthquake Hazard For Las Vegas Valley, Nevada Incorporating Probabilistic Hazard Assessment And Non--Linear Site Response, Suchan Lamichhane

UNLV Theses, Dissertations, Professional Papers, and Capstones

Abstract from Manuscript 1, "An alternative analysis of the probabilistic seismic hazard for Las Vegas Valley, Nevada": Probabilistic seismic hazard calculations relevant for rock-site conditions in the Las Vegas Valley, Nevada (LVV) have been computed that account for seismic sources that are not included in the current (2008) USGS national seismic hazard model (NSHM) because of insufficient knowledge or documentation, using the commercial software package EZ-FRISK. The LVV is underlain by a system of mapped, active normal faults that comprise the Las Vegas Valley Fault System (LVVFS), with maximum potential earthquakes to M6.8. The 2008 NSHM explicitly includes only one …


Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer Aug 2014

Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer

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

Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.

Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station …


A Geospatial Approach For Prioritizing Wind Farm Development In Northeast Nebraska, Usa, Adam Miller, Ruopu Li Jul 2014

A Geospatial Approach For Prioritizing Wind Farm Development In Northeast Nebraska, Usa, Adam Miller, Ruopu Li

School of Natural Resources: Faculty Publications

Being cleaner and climate friendly, wind energy has been increasingly utilized to meet the ever-growing global energy demands. In the State of Nebraska, USA, a wide gap exists between wind resource and actual energy production, and it is imperative to expand the wind energy development. Because of the formidable costs associated with wind energy development, the locations for new wind turbines need to be carefully selected to provide the greatest benefit for a given investment. Geographic Information Systems (GIS) have been widely used to identify the suitable wind farm locations. In this study, a GIS-based multi-criteria approach was developed to …


Interpolating Beach Profile Data Using Linear And Non-Linear Functions, Lance Calloway Croft Jul 2014

Interpolating Beach Profile Data Using Linear And Non-Linear Functions, Lance Calloway Croft

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Beach and nearshore surveys are conducted in a variety of ways, the most commonly used being the level-and-transit method; because it is inexpensive, time conducive and highly accurate. Specifically, beach surveys are conducted to better understand cross-shore, long-shore sediment transport processes, as well as to quantify volume changes, which are used to evaluate beach performance. In this study, a section of the beach on Sand Key, FL was surveyed using rod-and-transit. In addition to the commonly used linear data analysis, a non-linear analysis was conducted using NURBS (Non-Uniform Rational B-Splines).

Survey data was collected within a short time window …


Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou Jul 2014

Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou

Open Access Theses

Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …


Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani Jun 2014

Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Uncertainties are an unfortunate yet inevitable part of any forecasting system. Within the context of seasonal hydrologic predictions, these uncertainties can be attributed to three causes: imperfect characterization of initial conditions, an incomplete knowledge of future climate and errors within computational models. This study proposes a method to account for all threes sources of uncertainty, providing a framework to reduce uncertainty and accurately convey persistent predictive uncertainty. In currently available forecast products, only a partial accounting of uncertainty is performed, with the focus primarily on meteorological forcing. For example, the Ensemble Streamflow Prediction (ESP) technique uses meteorological climatology to estimate …


Estimating Unsaturated Flow Properties In Coarse Conglomeratic Sediment, Michael James Thoma Jr. May 2014

Estimating Unsaturated Flow Properties In Coarse Conglomeratic Sediment, Michael James Thoma Jr.

Boise State University Theses and Dissertations

In this dissertation, I address the lack of knowledge of unsaturated flow in coarse, conglomeratic sediment by determining if functional θ-ψ-K relationships, specifically van Genuchten-Mualem (VGM) relationships, developed to predict unsaturated flow in relatively fine-grained sediment can be directly applied to coarse, conglomeratic sediment. In the summer of 2011, a field-scale infiltration test was conducted at the Boise Hydrogeophysical Research Site to determine if functional ψ-θ-K relationships could be applied to infiltration in coarse, conglomeratic sediment, and to estimate parameter values for the VGM relationships. Vertically and laterally distributed ψ(t) and θ( …


Finite Difference Modeling Of Surface-~Wave Scattering For Shallow Cavity Detection, Heston Travis Norcott May 2014

Finite Difference Modeling Of Surface-~Wave Scattering For Shallow Cavity Detection, Heston Travis Norcott

UNLV Theses, Dissertations, Professional Papers, and Capstones

Data collection and analysis of scattering of Rayleigh-type surface waves are investigated for locating shallowly buried cavities. Surface-based seismic experiments conducted by others at the University of Nevada, Las Vegas (UNLV) Engineering Geophysics Test Site (EGTS) demonstrate scattering of Rayleigh waves caused by buried empty barrels (essentially air-filled cavities). The interpretation of the data is complicated by factors such as the presence of a high-velocity geologic layer just below the cavity.

This research uses a finite-difference seismic wave propagation code to compute time histories for a model that represents the Engineering Geophysics Test Site. By adding cavities to a background …


Determining The Dynamics Of Agricultural Water Use: Cases From Asia And Africa, Lisa-Maria Rebelo, Robyn Johnston, Poolad Karimi, Peter G. Mccornick Apr 2014

Determining The Dynamics Of Agricultural Water Use: Cases From Asia And Africa, Lisa-Maria Rebelo, Robyn Johnston, Poolad Karimi, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Across Africa and Asia, water resources are being affected by a complex mixture of social, economic, and environmental factors. These include climate change and population growth, food prices, oil prices, financial disruptions, and political fluctuations. The need to produce more food will have one of the largest impacts on water and will continue to reshape the patterns of agricultural water use in major food-growing regions. With this increasing demand on water for agriculture, from large-scale irrigation to intensification of rainfed systems, it is becoming increasingly important to ensure that water resources decision-making has access to information that captures the spectrum …


Floodplain Mapping Using Soil Survey Geographic (Ssurgo) Database, Nikhil Sangwan Apr 2014

Floodplain Mapping Using Soil Survey Geographic (Ssurgo) Database, Nikhil Sangwan

Open Access Theses

Floods are the most damaging of all natural disasters, adversely affecting millions of lives and causing financial losses worth billions of dollars every year across the globe. Flood inundation maps play a key role in assessment and mitigation of the potential flood hazards. However, there are several communities in the United States for which the flood risk maps have not been published yet, as the current flood inundation mapping methods are typically very expensive and time consuming. The objective of this study is to develop and examine an economical alternative approach to floodplain mapping using widely available soil survey data. …


Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer Mar 2014

Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer

Publications and Research

The assumption that the economic growth seen in recent decades will continue has dominated the discussion of future greenhouse gas emissions and the mitigation of and adaptation to climate change. Given that long-term economic growth is uncertain, the impacts of a wide range of growth trajectories should be considered. In particular, slower economic growth would imply that future generations will be relatively less able to invest in emissions controls or adapt to the detrimental impacts of climate change. Taking into consideration the possibility of economic slowdown therefore heightens the urgency of reducing greenhouse gas emissions now by moving to renewable …


Improving The Treatment Of Non-Aqueous Phase Tce In Low Permeability Zones With Permanganate, Chanat Chokejaroenrat, Steve D. Comfort, Chainarong Sakulthaew, Bruce I. Dvoark Mar 2014

Improving The Treatment Of Non-Aqueous Phase Tce In Low Permeability Zones With Permanganate, Chanat Chokejaroenrat, Steve D. Comfort, Chainarong Sakulthaew, Bruce I. Dvoark

Nebraska Water Center: Faculty Publications

Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is aparticularly challenging issue for injection-based remedial treatments. Our objective was to improve thesweeping efficiency of permanganate (MnO4−) into LPZs to treat high concentrations of TCE. This wasaccomplished by conducting transport experiments that quantified the penetration of various perman-ganate flooding solutions into a LPZ that was spiked with non-aqueous phase14C-TCE. The treatments weevaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilizationaids that minimized MnO2rind formation and (iii) a phase-transfer catalyst. In addition, we quantifiedthe ability of these flooding solutions to improve TCE destruction under batch …


Is Horizon Sampling More Powerful Than Depth Sampling?, Chris E. Johnson Mar 2014

Is Horizon Sampling More Powerful Than Depth Sampling?, Chris E. Johnson

Civil and Environmental Engineering - All Scholarship

No abstract provided.


Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Kilic, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu Jan 2014

Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Kilic, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu

School of Natural Resources: Faculty Publications

Landsat 8, a NASA and USGS collaboration, acquires global moderate-resolution measurements of the Earth's terrestrial and polar regions in the visible, near-infrared, short wave, and thermal infrared. Landsat 8 extends the remarkable 40 year Landsat record and has enhanced capabilities including new spectral bands in the blue and cirrus cloud-detection portion of the spectrum, two thermal bands, improved sensor signal-to-noise performance and associated improvements in radiometric resolution, and an improved duty cycle that allows collection of a significantly greater number of images per day. This paper introduces the current (2012–2017) Landsat Science Team's efforts to establish an initial understanding of …


Water Metrics, Lisa-Maria Rebelo, Jean-Marc Faurès, Poolad Karimi, Wim Bastiaanssen, Meredith Giordano, Vladimir Smakhtin, Peter G. Mccornick Jan 2014

Water Metrics, Lisa-Maria Rebelo, Jean-Marc Faurès, Poolad Karimi, Wim Bastiaanssen, Meredith Giordano, Vladimir Smakhtin, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Society has a universal need for water that crosses all sectors of activity. We need to be able to measure progress towards sustainable water for all by working towards targets that consider the different dimensions of water resources and use, including water quantity and quality. A suite of indicators that reflect water use by different sectors is needed to measure progress towards the forthcoming SDGs’ [sustainable development goals] water-related targets. Such indicators will need to rely on national data, must consider the variation in data availability, and can be complemented with new cost-effective ways for data collection.

Remote sensing measurements, …


Water-Food-Energy Nexus, Jeremy Bird, Felix Dodds, Peter G. Mccornick, Tushaar Shah Jan 2014

Water-Food-Energy Nexus, Jeremy Bird, Felix Dodds, Peter G. Mccornick, Tushaar Shah

Daugherty Water for Food Global Institute: Faculty Publications

The proposed SDGs on water, food and energy security all include targets on increasing efficiencies. Yet the water–food–energy nexus has multiple dimensions that, if managed in isolation, will compromise a nation’s ability to achieve the full portfolio of SDGs.

Climate change introduces additional uncertainties, further increasing tensions between sectors for access to water. Conventional energy and food production are emitters of greenhouse gases, but measures to reduce emissions—including renewable energy interventions, such as subsidies for biofuel production—can have adverse consequences on food prices.

To achieve desirable and sustainable outcomes for water, food, and energy requires investigating these elements as an …


Afrontar El Cambio: Cuidar Del Agua, De La Agricultura Y De La Seguridad Alimentaria En Una Era De Incertidumbre Climática, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre Jan 2014

Afrontar El Cambio: Cuidar Del Agua, De La Agricultura Y De La Seguridad Alimentaria En Una Era De Incertidumbre Climática, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre

Daugherty Water for Food Global Institute: Faculty Publications

En 1950, la población mundial era apenas superior a los 2500 millones de habitantes. En 2013, ronda los 7 mil millones. Aunque el crecimiento de la población se está ralentizando, se estima que en 2050 se alcanzarán los 9600 millones de habitantes. El aumento de la población será mayor en los países en desarrollo, donde los alimentos a menudo escasean, y la tierra y el agua están sometidas a presión. Para alimentar a la población mundial en 2050, tendrán que producirse más alimentos sin que haya un aumento significativo del terreno de cultivo y contando con un caudal menor de …


Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Peter G. Mccornick Jan 2014

Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 years old) who are lifelong residents of 33 rural communities in which groundwater concentrations of F− cover a wide range. A subset of 156 children was selected for urinary F− measurements. Our results showed that the mean F− concentrations in groundwater were 8.5 ± 4.1 mg/L (range: 1.1–18 mg/L), while those in urine …


The Effect Of Non-Fluoride Factors On Risk Of Dental Fluorosis: Evidence From Rural Populations Of The Main Ethiopian Rift, Julia Kravchenko, Tewodros Rango, Igor Akushevich, Behailu Atlaw, Peter G. Mccornick, R. Brittany Merola, Christopher Paul, Erika Weinthal, Courtney Harrison, Avner Vengosh, Marc Jeuland Jan 2014

The Effect Of Non-Fluoride Factors On Risk Of Dental Fluorosis: Evidence From Rural Populations Of The Main Ethiopian Rift, Julia Kravchenko, Tewodros Rango, Igor Akushevich, Behailu Atlaw, Peter G. Mccornick, R. Brittany Merola, Christopher Paul, Erika Weinthal, Courtney Harrison, Avner Vengosh, Marc Jeuland

Daugherty Water for Food Global Institute: Faculty Publications

Elevated level of fluoride (F−) in drinking water is a well-recognized risk factor of dental fluorosis (DF). While considering optimization of region-specific standards for F−, it is reasonable, however, to consider how local diet, water sourcing practices, and non-F− elements in water may be related to health outcomes. In this study, we hypothesized that non-F− elements in groundwater and lifestyle and demographic characteristics may be independent predictors or modifiers of the effects of F− on teeth. Dental examinations were conducted among 1094 inhabitants from 399 randomly selected households of 20 rural communities of …


Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Paul Mccornick Jan 2014

Fluoride Exposure From Groundwater As Reflected By Urinary Fluoride And Children’S Dental Fluorosis In The Main Ethiopian Rift Valley, Tewodros Rango, Avner Vengosh, Marc Jeuland, Redda Tekle-Haimanot, Erika Weinthal, Julia Kravchenko, Christopher Paul, Paul Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 This cross-sectional study explores the relationships between children’s F− exposure from drinking groundwater and urinary F− concentrations, combined with dental fluorosis (DF) in the Main Ethiopian Rift (MER) Valley. We examined the DF prevalence and severity among 491 children (10 to 15 years old) who are lifelong residents of 33 rural communities in which …


On Target For People And Planet: Setting And Achieving Water-Related Sustainable Development Goals, Julie Van Der Bliek, Peter G. Mccornick, James Clarke Jan 2014

On Target For People And Planet: Setting And Achieving Water-Related Sustainable Development Goals, Julie Van Der Bliek, Peter G. Mccornick, James Clarke

Daugherty Water for Food Global Institute: Faculty Publications

Our specific focus in this book is on securing water for sustainable food production. This links to sustainable water resources management, delivering on the water supply and sanitation requirements and provisioning water for energy and the urban sector. A specific intent is to ensure that the realities in low- and middle-income countries in Africa and Asia are recognized and to provide practical pathways to change that fit these realities and the aspirations of those countries. This will help to prepare for the next step in the SDG [sustainable development goals] process: devolving the SDGs to the national level. It will …


Co-Occurrence Of The Cyanotoxins Bmaa, Daba And Anatoxin-A In Nebraska Reservoirs, Fish, And Aquatic Plants, Maitham Ahmed Al-Sammak, Kyle D. Hoagland, David A. Cassada, Daniel D. Snow Jan 2014

Co-Occurrence Of The Cyanotoxins Bmaa, Daba And Anatoxin-A In Nebraska Reservoirs, Fish, And Aquatic Plants, Maitham Ahmed Al-Sammak, Kyle D. Hoagland, David A. Cassada, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Several groups of microorganisms are capable of producing toxins in aquatic environments. Cyanobacteria are prevalent blue green algae in freshwater systems, and many species produce cyanotoxins which include a variety of chemical irritants, hepatotoxins and neurotoxins. Production and occurrence of potent neurotoxic cyanotoxins β-N-methylamino-L-alanine (BMAA), 2,4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with environmental implications to public and animal health. Biomagnification, though not well understood in aquatic systems, is potentially relevant to both human and animal health effects. Because little is known regarding their presence in fresh water, we investigated the occurrence and potential for bioaccumulation of cyanotoxins …


A Review Of The Hyporheic Zone, Stream Restoration, And Means To Enhance Denitrification, Leanne Merill, David J. Tonjes Jan 2014

A Review Of The Hyporheic Zone, Stream Restoration, And Means To Enhance Denitrification, Leanne Merill, David J. Tonjes

Technology & Society Faculty Publications

The hyporheic zone is the subsurface area below and adjacent to a stream where groundwater mixes with stream water, through vertical, lateral, and longitudinal flows. The hyporheic zone connects the stream to uplands and other terrestrial environments. It is a zone of distinct faunal communities, high biological diversity and ecological complexity, and is the site of chemical processing and transformations of ground- and stream waters. The hyporheic zone is important to the overall ecosystem ecology of the stream, and it can influence stream water chemistry. Flows, reactions, and biota in the hyporheic zone are heterogeneous and patchy, making it difficult …


Why Ricker Wavelets Are Successful In Processing Seismic Data: Towards A Theoretical Explanation, Afshin Gholamy Salehabady Jan 2014

Why Ricker Wavelets Are Successful In Processing Seismic Data: Towards A Theoretical Explanation, Afshin Gholamy Salehabady

Open Access Theses & Dissertations

In many engineering applications ranging from engineering seismology to petroleum engineering and civil engineering, processing seismic data plays a key role. In processing seismic data, it turns out to be very efficient to describe the signal's spectrum as a linear combination of Ricker wavelet spectra.

In this Thesis, we provide a possible theoretical explanation for this empirical efficiency. Specifically, signal propagation through several layers is discussed, and it is shown that the Ricker wavelet is the simplest non-trivial solution for the corresponding data processing problem, under the condition that the described properties of the approximation family are satisfied.


Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui Jan 2014

Methods For Estimating Sediment Yield And Dam Capacity In The Great Lakes Watershed, Jennifer Hui

Wayne State University Theses

Sedimentation is the most important factor in the longevity of dams built in the United States. As most dams are reaching their capacity for sediment storage, this study investigated the historical and predicted future rates of sediment accumulation as well as the remaining storage capacity. This study examined the mechanisms influencing sediment production and storage in the watershed to provide future insight regarding potential control of this process. Twelve reservoirs throughout the Great Lakes watershed were selected and analyzed for their greater applicability to the entire watershed. Both historic and new data were collected on these dams to determine how …


Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova Jan 2014

Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

A description of finite element model and analysis of a shell with an infill is performed. A large diameter thin cylindrical shell structure with the edge leaning against compressible foundation soil is analyzed. Different materials are considered individually for the models of each structure shell and infill component (metal or reinforced concrete shell, and granular or elastic infill in a shell and foundation soil loaded by the structure). Contact conditions between 1) the infill and the shell’s inner surface and 2) between the foundation material and the shell edge are analyzed. An example of calculating strain conditions in the shell …


Coupled Sediment Yield And Sediment Transport Model To Support Navigation Planning In Northeast Brazil, Calvin Trebor Creech Jan 2014

Coupled Sediment Yield And Sediment Transport Model To Support Navigation Planning In Northeast Brazil, Calvin Trebor Creech

Wayne State University Dissertations

Deposition of sediment (shoaling) in commercial waterways is a major obstacle to maintaining sustainable riverine transportation of bulk goods (primarily agricultural and mining commodities). The rate of aggradation of sediment in a waterway is directly related to both the rate of sediment erosion from upland and river bank sources (sediment yield) and the energy in the river to effectively transport the sediment through the waterway system (sediment transport). Historically, methods used for waterway development have included trial and error or rules of thumb associated with river training structures and chute cut-off canals or engineering of navigation locks and dams. More …


Drainage Structure Datasets And Effects On Lidar-Derived Surface Flow Modeling, Ruopu Li, Zhenghong Tang, Xu Li, Jessie Winter Dec 2013

Drainage Structure Datasets And Effects On Lidar-Derived Surface Flow Modeling, Ruopu Li, Zhenghong Tang, Xu Li, Jessie Winter

School of Natural Resources: Faculty Publications

With extraordinary resolution and accuracy, Light Detection and Ranging (LiDAR)-derived digital elevation models (DEMs) have been increasingly used for watershed analyses and modeling by hydrologists, planners and engineers. Such high-accuracy DEMs have demonstrated their effectiveness in delineating watershed and drainage patterns at fine scales in low-relief terrains. However, these high-resolution datasets are usually only available as topographic DEMs rather than hydrologic DEMs, presenting greater land roughness that can affect natural flow accumulation. Specifically, locations of drainage structures such as road culverts and bridges were simulated as barriers to the passage of drainage. This paper proposed a geospatial method for producing …