Engineering Commons^™

Enhancement Of The Performance Of Gaas Based Solar Cells By Using Plasmonic, Anti-Reflection Coating And Hydrophobic Effects, Yahia Fayiz Makableh

Graduate Theses and Dissertations

Investigation of renewable energy resources is gaining huge momentum in recent years due to the limited fossil fuels, and their detriment impact on the environment. Solar energy is promising to meet the increased energy demand. In order to achieve this goal, solar energy has to be harvested efficiently at low cost. Therefore, higher efficiency solar cells are the primary focus of research worldwide. Photovoltaics based on InAs/GaAs intermediate band solar cells and their device performance enhancements are investigated in this dissertation. The device enhancement is carried out by surface modification methods. The dissertation work is inspired by the need of …

Top-Down Aluminum Induced Crystallization For Photovoltaics, Seth Daniel Shumate

Graduate Theses and Dissertations

Passivating silicon solar cell surfaces is critical to fabricating very high efficiency and low cost photovoltaic devices. The sun-facing surface of the solar cell, known as the emitter, is particularly important when designing a solar cell. This work focused first on an alternative method of forming the emitter of silicon solar cells, and secondly on a method for improving the surface passivation of both these non-traditional and standard n-type solar cells.

Top-down aluminum induced crystallization (TAIC) was used for forming a polycrystalline silicon layer from amorphous silicon using aluminum to catalyze the crystallization at much lower temperatures than otherwise possible. …

Decision Environments To Encourage More Sustainable Infrastructure Outcomes, Earl Shealy

All Dissertations

Physical infrastructure (i.e. roads, pipelines, airports, dams, landfills, and water treatment systems) contributes directly to sustainability outcomes such as energy and water use and climate changing emissions. The infrastructure built today will likely impact future generations for many years. Planning, design and development decisions about infrastructure are critical to the future performance of these systems. Such decisions about infrastructure are complex with multiple variables, alternative options, and design stages. To manage decisions that exceed cognitive capacity to consider all options, decision makers often create mental shortcuts (heuristics), and accompanied errors (biases). The potential cognitive biases when dealing with complex decisions …

Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer

Graduate Theses and Dissertations

With the increase in energy demand by the residential community in this country and the diminishing fossil fuel resources being used for electric energy production there is a need for a system to efficiently manage power within a residence. The Smart Green Power Node (SGPN) is a next generation energy management system that automates on-site energy production, storage, consumption, and grid usage to yield the most savings for both the utility and the consumer. Such a system automatically manages on-site distributed generation sources such as a PhotoVoltaic (PV) input and battery storage to curtail grid energy usage when the price …

Incorporating Environmental And Social Factors Into Decision-Making Of An Oil And Gas Industry To Improve Sustainability, Gaurav Dabhadkar

Graduate Theses and Dissertations

The energy industry (including the oil and gas industry) is facing unparalleled scrutiny and demands from stakeholders including investors, regulators (industry and environmental), communities, and other stakeholders. Sustainable development is one of the major concerns of the oil and gas industry. Companies are seeking to increase sustainability of their operations by considering environmental and Social concerns in addition to economic concerns. Oil and gas companies need to take decisions at different stages of the product life cycle (e.g. planning, design, exploration, production, and clean-up) which have direct or indirect impact on the organization's objectives. Addressing economic, technical, Social, and environmental …

Using The Triple Bottom Line To Select Sustainable Suppliers For A Major Oil And Gas Company, Pandarinath Adarsh Sunkari

Graduate Theses and Dissertations

Companies have primarily been focusing on the financial bottom line i.e., on increasing profits by increasing revenues and reducing costs. With high energy usage and environmental change posing threats to the environment and business operations, companies are now considering sustainability. Since some global suppliers have low cost labor, Social well-being and human development has also emerged as major goals of a company performing global operations. Focusing on these three goals is termed the "Triple Bottom Line" (TBL). We study and explore the TBL benefits that could be realized by an oil and gas company by focusing on sustainable suppliers. A …

Impacts Of Ozone Dose And Empty Bed Contact Time On Total Organic Carbon Removal Through Ozone-Biological Activated Carbon Treatment, Ashley Selvy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the face of climate change, pollution, and population growth, water scarcity has become a global threat. Many populations have witnessed their drinking water sources dwindle to an unsustainable level. These severe conditions have sparked interest in potable reuse as an increasingly viable alternative to typical ‘pristine’ drinking water sources. Currently, the California Division of Drinking Water (DDW) provides the most stringent requirements for reuse water quality. The best way to meet these standards is through the use of full advanced treatment (FAT), which consists of reverse osmosis (RO) and an advanced oxidation process (AOP). Alternative treatment trains composed of …

Mapping Regional Inundation With Spaceborne L-Band Sar, Bruce Chapman, Kyle Macdonald, Masanobu Shimada, Ake Rosenqvist, Ronny Schroeder, Laura Hess

Publications and Research

Shortly after the launch of ALOS PALSAR L-band SAR by the Japan Space Exploration Agency (JAXA), a program to develop an Earth Science Data Record (ESDR) for inundated wetlands was funded by NASA. Using established methodologies, extensive multi-temporal L-band ALOS ScanSAR data acquired bi-monthly by the PALSAR instrument onboard ALOS were used to classify the inundation state for South America for delivery as a component of this Inundated Wetlands ESDR (IW-ESDR) and in collaboration with JAXA’s ALOS Kyoto and Carbon Initiative science programme. We describe these methodologies and the final classification of the inundation state, then compared this with results …

Odu Students Work On Nation's First Climate Change Adapted Neighborhood, Jugal Patel

News Items

No abstract provided.

Probabilistic Precipitation Estimation With A Satellite Product, Nir Y. Krakauer, Soni M. Pradhanang, Jeeban Panthi, Tarendra Lakhankar, Ajay K. Jha

Publications and Research

Satellite-based precipitation products have been shown to represent precipitation well over Nepal at monthly resolution, compared to ground-based stations. Here, we extend our analysis to the daily and subdaily timescales, which are relevant for mapping the hazards caused by storms as well as drought. We compared the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B42RT product with individual stations and with the gridded APHRODITE product to evaluate its ability to retrieve different precipitation intensities. We find that 3B42RT, which is freely available in near real time, has reasonable correspondence with ground-based precipitation products on a daily timescale; rank …

Life-Cycle Energy And Ghg Emissions Of Forest Biomass Harvest And Transport For Biofuel Production In Michigan, Fengli Zhang, Dana M. Johnson, Jinjiang Wang

College of Business Publications

High dependence on imported oil has increased U.S. strategic vulnerability and prompted more research in the area of renewable energy production. Ethanol production from renewable woody biomass, which could be a substitute for gasoline, has seen increased interest. This study analysed energy use and greenhouse gas emission impacts on the forest biomass supply chain activities within the State of Michigan. A life-cycle assessment of harvesting and transportation stages was completed utilizing peer-reviewed literature. Results for forest-delivered ethanol were compared with those for petroleum gasoline using data specific to the U.S. The analysis from a woody biomass feedstock supply perspective uncovered …

On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan

Journal of the South Carolina Academy of Science

Models which can estimate environmental transport of radioactive contaminants in natural and engineered systems are required to 1) deploy effective remediation strategies for contaminated sites, 2) design waste repositories for future waste streams, and 3) ensure protection of human and environmental health in all cases. These models require accurate transport parameters in order to correctly predict how these contaminants will move in the subsurface. This work aimed to determine more accurately the distribution coefficients for radium and strontium sorption to Savannah River Site (SRS) soils. Radium and strontium sorption to the soils was found to be highly dependent upon ionic …

Should Nuclear Energy Be More Heavily Incorporated By The United States?, Matthew Romer

Nebraska College Preparatory Academy: Senior Capstone Projects

America is involved in one of the biggest races towards electrical efficiency, cleanliness, and productivity. Nuclear energy is a major part of the U.S.’s non-­‐carbon emitting electricity, and has strict regulations for management. However, this form of energy has been on the decline in the past couple decades due to cost and competition with cheaper, less clean methods. Is nuclear energy feasible enough to continue?

Spatial Analysis Of Passenger Vehicle Use And Ownership And Its Impact On The Sustainability Of Highway Infrastructure Funding, Matthew Volovski

Open Access Dissertations

Across the United States, the sustainability of highway funding is at risk due to increasing need and uncertainty in the factors that drive revenue. Past studies on highway funding sustainability have identified that the root cause of changing highway revenue are the shifts in social demographics and economic characteristics. Unfortunately, from the revenue perspective (the focus of this dissertation), the ability of previous research to account for these factors has been rather limited in two ways; first, the inability to accurately assess current regional vehicle use (a typical prerequisite for statistical modeling of highway revenues) due to difficulties associated with …

International Water And Food Security Development: Performance Evaluation And Assessment Of Research Needs At Multiple Scales, Caitlin Anne Grady

Open Access Dissertations

Water and food security remain the top development challenges of the decade, and perhaps the century. Since the Millennium Development Goals were established in 2000, billions of people have obtained access to more food, better nutrition, improved water, and basic sanitation facilities worldwide. This progress has been accomplished through the dedication of international organizations, non-governmental organizations, country-level governments, private corporations, and individuals at international, regional, and local scales. Truly tremendous strides have been made in water and food provisioning for humans worldwide. These past two decades have also seen the largest population growth on record, the highest rates of childhood …

Spatial And Temporal Variability Of Rainfall In The Gandaki River Basin Of Nepal Himalaya, Jeeban Panthi, Piyush Dahal, Madan Lall Shrestha, Suman Aryal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha, Mohan Sharma, Ramchandra Karki

Publications and Research

Landslides, floods, and droughts are recurring natural disasters in Nepal related to too much or too little water. The summer monsoon contributes more than 80% of annual rainfall, and rainfall spatial and inter-annual variation is very high. The Gandaki River, one of the three major rivers of Nepal and one of the major tributaries of the Ganges River, covers all agro-ecological zones in the central part of Nepal. Time series tests were applied for different agro-ecological zones of the Gandaki River Basin (GRB) for rainfall trends of four seasons (pre-monsoon, monsoon, post-monsoon and winter) from 1981 to 2012. The non-parametric …

Nebraska’S Natural Resources Districts: An Assessment Of A Large-Scale Locally Controlled Water Governance Framework, Ann Bleed, Christina Hoffman Babbitt

Daugherty Water for Food Global Institute: Faculty Publications

In 1972 the State of Nebraska created the Natural Resources Districts (NRDs) to consolidate a multitude of single-purpose local natural resource districts into a more comprehensive, holistic, and efficient natural resources governance system. While consolidation and efficiency was important, so was the concept of maintaining local control. Thus, Nebraska rejected the governance framework of a single top-down state agency, preferring to create NRDs that are each governed by a locally elected board. The locally elected governing boards of the NRDs were given broad authorities over many of the state’s natural resources, including groundwater. Such a governance structure was, and to …

Moor Movement: Automated Docking On Drought-Stricken Reservoirs, Daniel Beck

Landscape Architecture

Moor Movement establishes a mechanized docking system for unpredictable shoreline fluctuations on inland lakes and reservoirs. Due to climate change and warmer global temperatures, the threat of ocean level rise has initiated massive proposals to address the interface between ocean and man-made infrastructure. While this is a monumental problem, ocean level rise is not the only immediate threat. The recently declared emergency drought conditions in California are finally bringing attention to inland lakes and reservoirs. While ocean levels might rise 2-7 feet in 100 years, a lake could drop 100 feet in 5 years. What happens to access roads, marinas, …

Sustainability, Efficiency And Equitability Of Water Consumption And Pollution In Latin America And The Caribbean, Mesfin Mekonnen, Markus Pahlow, Maite M. Aldaya, Erika Zarate

Daugherty Water for Food Global Institute: Faculty Publications

This paper assesses the sustainability, efficiency and equity of water use in Latin America and the Caribbean (LAC) by means of a geographic Water Footprint Assessment (WFA). It aims to provide understanding of water use from both a production and consumption point of view. The study identifies priority basins and areas from the perspectives of blue water scarcity, water pollution and deforestation. Wheat, fodder crops and sugarcane are identified as priority products related to blue water scarcity. The domestic sector is the priority sector regarding water pollution from nitrogen. Soybean and pasture are priority products related to deforestation. We estimate …

Bakken Flares And Satellite Images, University Of North Dakota. Energy And Environmental Research Center, Xiaodong Zhang

EERC Brochures and Fact Sheets

Fact sheet refuting a magazine article about Bakken gas flares and satellite images. Includes research into gas flares and satellite images by the University of North Dakota and the Energy & Environmental Research Center. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Does Material Choice Drive Sustainability Of 3d Printing?, Jeremy Faludi, Zhongyin Hu, Shahd Alrashed, Christopher Braunholz, Suneesh Kaul, Leulekal Kassaye

Dartmouth Scholarship

Environmental impacts of six 3D printers using various materials were compared to determine if material choice drove sustainability, or if other factors such as machine type, machine size, or machine utilization dominate. Cradle-to-grave life-cycle assessments were performed, comparing a commercial-scale FDM machine printing in ABS plastic, a desktop FDM machine printing in ABS, a desktop FDM machine printing in PET and PLA plastics, a polyjet machine printing in its proprietary polymer, an SLA machine printing in its polymer, and an inkjet machine hacked to print in salt and dextrose. All scenarios were scored using ReCiPe Endpoint H methodology to combine …

Sensible Air To Air Heat Recovery Strategies In A Passive House, Santiago Martin Rodriguez-Anderson

Dissertations and Theses

Due to rising energy costs and concerns about global climate change, high performance buildings are more in demand than ever before. With roughly 20% of the total energy consumption in the United States being devoted to residential use, this sector represents a significant opportunity for future savings. There are many guidelines and standards for reducing building energy consumption. One of the most stringent is the Passive House Standard. The standard requires that that air infiltration is less than or equal to 0.6 air changes per hour at a 50 Pascal pressure difference (ACH 50), annual heating energy is less than …

2015 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …

Double Vault Composting Latrines In Rural Paraguay : Feasible Construction And Optimal Use, Paul T. Pebler

Dissertations, Master's Theses and Master's Reports - Open

Water resource depletion and sanitation are growing problems around the world. A solution to both of these problems is the use of composting latrines, as it requires no water and has been recommended by the World Health Organization as an improved sanitation technology. However, little analysis has been done on the decomposition process occurring inside the latrine, including what temperatures are reached and what variables most affect the composting process. Having better knowledge of how outside variables affect composting latrines can aid development workers on the choice of implementing such technology, and to better educate the users on the appropriate …

Nephrotoxic Contaminants In Drinking Water And Urine, And Chronic Kidney Disease In Rural Sri Lanka, Tewodros Rango, Marc Jeuland, Herath Manthrithilake, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Chronic kidney disease of unknown (“u”) cause (CKDu) is a growing public health concern in Sri Lanka. Prior research has hypothesized a link with drinking water quality, but rigorous studies are lacking. This study assesses the relationship between nephrotoxic elements (namely arsenic (As), cadmium (Cd), lead (Pb), and uranium (U)) in drinking water, and urine samples collected from individuals with and/or without CKDu in endemic areas, and from individuals without CKDu in nonendemic areas. All water samples—from a variety of source types (i.e., shallow and deep wells, springs, piped, and surface water)—contained extremely low concentrations of nephrotoxic elements, and all …

Demonstration Of A Daily High-Resolution (375-M) Alexi Evapotranspiration Product For The Nena Region, Christopher Hain, Martha C. Anderson, Mitch Schull, Christopher M.U. Neale

Daugherty Water for Food Global Institute: Faculty Publications

While the current constellation of geostationary sensors provides near-global coverage (60N to 60S) – it requires merging data from 7 satellites [resolving time differences; view angles; atmospheric correction]. Polar orbiting sensors such as MODIS and VIIRS provide daily global coverage of LST at higher resolutions than GEO sensors but at only two times per day.

Assessment Of Village Chicken Production Systems In Kambata Tambaro And Wolaita Zones, Snnpr, Ethiopia, Aman Getiso, Fitsum Tessema, Mesfin Mekonnen, Addisu Jimma, Bereket Zeleke

Daugherty Water for Food Global Institute: Faculty Publications

The study was conducted in four woredas (Damot Gale,Of a, Angacha and Hadero Tunto) the first two of them found in Wolaita zone and two of them in Kambata Tambaro Zone of SNNPR, Ethiopia respectively. A cross-sectional survey was conducted in the study areas to assess village chicken production systems, productive and reproductive performance of village chicken and identifying constraints to village chicken production. Stratified random sampling technique was used to select 240 farming households and administer a pre-tested and structured questionnaire. The results showed that the mean age of interviewed farmers was 37.8±9.3 years; average family size & chicken …

Yield Gap Analysis Of Field Crops: Methods And Case Studies, V. O. Sadras, Kenneth Cassman, Patricio Grassini, W. G.M. Bastiaanssen, A. G. Laborte, A. E. Milne, G. Sileshi, P. Steduto

Daugherty Water for Food Global Institute: Faculty Publications

The challenges of global agriculture have been analysed exhaustively and the need has been established for sustainable improvement in agricultural production aimed at food security in a context of increasing pressure on natural resources. Whereas the importance of R&D investment in agriculture is increasingly recognised, better allocation of limited funding is essential to improve food production. In this context, the common and often large gap between actual and attainable yield is a critical target. Realistic solutions are required to close yield gaps in both small and large scale cropping systems worldwide; to make progress in this direction, we need (1) …

The Integration Of Heat Resources In A Solar Thermal-Heat Pump Hydronic System, John Maxfield Degrove

Open Access Theses

According to the U.S. Department of Energy, roughly 41% of the energy consumed in the U.S. is used the power buildings. Within that number, almost half is used to heat or cool the building. Current technologies allow for consistent thermal management, but most utilize energy harvested from fossil fuels or convert electricity back into thermal energy. Background literature shows that the utilization of alternative heat resources such as heat pumps and solar thermal collectors can greatly reduce the energy used for heat delivery while producing adequate heating performance. A combined hydronic system using a bank of solar thermal collectors in …

2015 Nebraska Water Monitoring Programs Report, Marty Link, Ryan Chapman

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain high quality water and encourage or execute activities to improve poor water quality. Monitoring is done on nearly 17,000 miles of flowing rivers and streams, more than 134,000 acres of surface water in lakes and reservoirs, as well as the vast storage of groundwater in Nebraska’s aquifers.