Digital Commons Network^™

Bias Correction And Downscaling Of Climate Model Outputs Required For Impact Assessments Of Climate Change In The U.S. Northeast, Kazi F. Ahmed

Master's Theses

Global Climate Models (GCMs) are the typical sources of future climate data required for impact assessments of climate change. However, GCM outputs are related to model-related uncertainties and involve a great deal of biases. Bias correction of model outputs is, therefore, necessary before their use in impact studies. The coarse resolution of GCM simulations is another hindrance to their direct use in fine-scale impact analysis of climate change. Although downscaling of GCM outputs can be performed by dynamical downscaling using Regional Climate Models (RCMs), it requires large computational capacity. When daily climate data from multiple GCMs are required to be …

Environmental Sensor Anomaly Detection Using Learning Machines, Erick F. Conde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The search for improvements in the quality assurance/quality control (QA/QC) of real-time environmental measurements has been a field well exploited in recent years. These measurements describe actual environmental conditions and processes that provide relevant information upon which water quality management decisions are based. In situ sensors (located at the site of interest) are commonly used for such real-time measurement purposes. However, the performance of these types of sensors can be affected by such things as human factors, lack of necessary maintenance, flaws on the transmission line or any part of the sensor, and unexpected changes in the sensors surrounding conditions. …

Electrocatalytic Determination Of 15 Kinds Of Phenolic Compounds By Novel Gold Nanoparticles-Modified Glassy Carbon Electrode, Yan-Ping Cui, Wei-Xing Wang, Chang-Zhu Yang, Wen-Hong Pu

Journal of Electrochemistry

A gold nanoparticles modified glassy carbon electrode (Au/GCE) was used to detect 15 kinds of phenolic compounds. In the cyclic voltammetry measurements, the peak currents of phenolic compounds at Au/GCE were all increased as compared with GCE and planar gold electrodes, and the oxidation potentials were determined by the activity of analytes. Besides, electrocatalysis of salicylic acid was studied at Au/GCE. The results showed that, there was a good linear relationship between the oxidation current and the concentration of salicylic acid, and the current sensitivity was 1.8 fold higher than that obtained on GCE. Trace phenolic compounds determination could be …

Visko: Semantic Web Support For Information And Science Visualization, Nicholas Del Rio, Paulo Pinheiro Da Silva

Departmental Technical Reports (CS)

Hrc Enews — 2011 Fall, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

Thirdhand Tobacco Smoke: Emerging Evidence And Arguments For A Multidisciplinary Research Agenda, Georg E. Matt, Penelope J. Quintana, Hugo Destaillats, Lara A. Gundel, Mohamad Sleiman, Brett C. Singer, Peyton Jacob, Jonathan P. Winickoff, Prue Talbot, Suzaynn Schick, Yinsheng Wang, Bo Hang, Manuela Martins-Green, James F. Pankow, Melbourne F. Hovell, Neal L. Benowitz, Virender K. Rehan, Jonathan M. Samet

Civil and Environmental Engineering Faculty Publications and Presentations

There is broad consensus regarding the health impact of tobacco use and secondhand smoke exposure, yet considerable ambiguity exists about the nature and consequences of thirdhand smoke (THS). We introduce definitions of THS and THS exposure and review recent findings about constituents, indoor sorption-desorption dynamics, and transformations of THS; distribution and persistence of THS in residential settings; implications for pathways of exposure; potential clinical significance and health effects; and behavioral and policy issues that affect and are affected by THS. Physical and chemical transformations of tobacco smoke pollutants take place over time scales ranging from seconds to months and include …

Raman Spectroscopic Study Of Solid Solution Spinel Oxides, Brian D. Hosterman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solid solution spinel oxides of composition MgxNi1−xCr2O4, NiFexCr2−xO4, and FexCr3−xO4 were synthesized and characterized using x-ray diffraction and Raman spectroscopy. Frequencies of the Raman-active modes are tracked as the metal cations within the spinel lattice are exchanged. This gives information about the dependence of the lattice vibrations on the tetrahedral and octahedral cations. The highest-frequency Raman-active mode, A1g, is unaffected by substitution of the divalent tetrahedral cation, whereas the lower frequency vibrations are more strongly affected by substitution of the tetrahedral cation. The change in wavenumber of many phonons is nonlinear upon cation exchange. All detected modes of MgxNi1−xCr2O4 and …

Structural, Electrical And Thermoelectric Properties Of Chromium Silicate Thin Films, Makram Abd El Qader

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thermoelectric devices can generate electrical power as a result of their ability to produce electrical currents in the presence of thermal gradients. They can also produce refrigerative cooling when electrical power is supplied to them. Among the potential semiconducting silicides, CrSi ₂ is attractive because of its high thermal and chemical stability and its potential for thermoelectric application. CrSi₂ /SiO₂ thin-film structures were prepared using RF sputtering. As deposited and annealed (300°C to 600°C) thin films were characterized for their structural, electrical, and thermoelectric transport properties. As-sputtered CrSi ₂ film is amorphous at room temperature and crystallizes around …

Developing A Hybrid Model To Predict Student First Year Retention And Academic Success In Stem Disciplines Using Neural Networks, Ruba Alkhasawneh

Theses and Dissertations

Understanding the reasoning behind the low enrollment and retention rates of Underrepresented Minority (URM) students (African Americans, Hispanic Americans, and Native Americans) in the disciplines of science, technology, engineering, and mathematics (STEM) has concerned many researchers for decades. Numerous studies have used traditional statistical methods to identify factors that affect and predict student retention. Recently, researchers have relied on using data mining techniques for modeling student retention in higher education [1]. This research has used neural networks for performance modeling in order to obtain an adequate understanding of factors related to first year academic success and retention of URM at …

A Viability Study Of Photovoltaic Systems, Youakim Kalaani, William Nichols

Electrical & Computer Engineering: Faculty Publications

Concerns over climate change and other environmental problems highlight a need for a shift toclean and renewable energy. The main objective of this study is to investigate the viability ofphotovoltaic electricity in the southeastern region of the United States. To achieve this goal, twocase studies were conducted involving a large retail store and a recreation center. Historical datarelated to weather conditions, solar energy and power demand were investigated and as a resultgrid-connected photovoltaic systems were designed to provide green energy for these facilities.Several engineering factors that went into the design process as well as economic andenvironmental considerations were thoroughly discussed …

Piedras Blancas Light Station Vista Point Improvement Plan, Larissa Heeren, Reuben Juster, Annamarie Usher, John Rossi, Nick Mitchell

Mechanical Engineering

Piedras Blancas Light station Improvement Involved the design of two separate parking lot/vista point plans as well as the creation of a concrete Iron Ranger located near the gift shop on site.

Unlv Stars Unabridged Report, University Of Nevada, Las Vegas

Reports (USI)

University of Nevada, Las Vegas, by earning a 2011 Silver Rating in the Sustainability Tracking, Assessment & Ratings System (STARS), is ahead of the curve among public universities – and improving.

STARS is a voluntary, self–reporting framework developed by the Association for the Advancement of Sustainability in Higher Education (AASHE) to help measure sustainability performance over time and among colleges and universities nationwide. The UNLV Sustainability Council oversaw STARS, which by measuring sustainability can help UNLV to reduce energy consumption and waste, improve education, attract research, and generate jobs.

A rating of Silver puts UNLV in great company – with …

Groundwater Research In Middle Earth, Thomas Lapoint

Liberal Arts and Engineering Studies

My senior project focused on studying saltwater intrusion in a coastal town of New Zealand. I feel lucky that I was able to travel to such a distant place, conduct research that was insightful and interesting, and immerse myself in an international culture all in the name of my education. As a Liberal Arts and Engineering Studies student, I aim to analyze not only the cultural differences and similarities that the foreign environment offers to me but also the detailed, technical, engineering aspect of my research. I believe that my education should be approached with a well rounded perspective that …

Factors For Improved Fish Passage Waterway Construction, David N. Sillars, Hamid Moradkhani, Nicholas Tymvios, Trevor D. Smith

TREC Final Reports

Streambeds are important fish passageways in Oregon; they provide for the necessary habitats and spawning cycles of a healthy fish population. Oregon state law requires that hydraulic structures located in water properly provide fish passage. Increasingly stringent state and federal regulations apply to these fish passageways, and designers must become more cognizant of conditions over a range of flows to accommodate fish movement and avoid expensive structural failure of these passageways. Fish passage structures are built when roads cross streambeds and may include culverts, or bridges. When these structures are built, the streambeds are re-created using a technique called “roughened …

Ecosystem Management Of The Missouri River From Gavins Point Dam To Ponca State Park, Nebraska, Robert S. Nebel

United States Army Corps of Engineers, Omaha District

•Authorized by a 1978 amendment to the National Parks and Recreation Act (PL 95- 625) which amended the Wild and Scenic Rivers Act of 1968 (PL 90-542)

• Corps is authorized to construct recreational development, bank stabilization, and other recreational river features as necessary to support the values for which the river was designated

• Life-of-project funding ceiling of $21 million; approximately $3.2 million spent to date

• The Corps and National Park Service signed a 1980 Cooperative Agreement outlining each agency's responsibilities

• The General Management Plan has recently been updated (1999) with an environmental emphasis

Statistical Comparisons Of Watershed-Scale Response To Climate Change In Selected Basins Across The United States, John Risley, Hamid Moradkhani, Lauren Hay, Steve Markstrom

Civil and Environmental Engineering Faculty Publications and Presentations

In an earlier global climate-change study, air temperature and precipitation data for the entire twenty-first century simulated from five general circulation models were used as input to precalibrated watershed models for 14 selected basins across the United States. Simulated daily streamflow and energy output from the watershed models were used to compute a range of statistics. With a side-by-side comparison of the statistical analyses for the 14 basins, regional climatic and hydrologic trends over the twenty-first century could be qualitatively identified. Low-flow statistics (95% exceedance, 7-day mean annual minimum, and summer mean monthly streamflow) decreased for almost all basins. Annual …

Structure Studies On Lanthanide Technetium Pyrochlores As Prospective Host Phases To Immobilize 99- Technetium And Fission Lanthanides From Effluents Of Reprocessed Used Nuclear Fuels, Thomas Hartmann, Ariana Alaniz

Festival of Communities: UG Symposium (Posters)

We performed a systematic investigation of the incorporation of 99Tc into pyrochlore oxide structures, Ln2Tc2O7, where Ln represents trivalent lanthanide Ln3+ cations, while 99Tc is atetravalent, Tc4+, metal cation. Pyrochlore compounds are high-melting temperature oxides and are recognized for their durability. Our goal in this preliminary study is to characterize and quantify the range of stability of the lanthanum technetium pyrochlore oxide phase. Hereby, powder X-ray diffraction (XRD) and Rietveld analysis were used to determine and characterize the crystalline phase content with high accuracy, and scanning electron microscopy (SEM) was used to characterize the microstructure and homogeneity of the synthesized …

Comprehensive Review And Application Of Particle Image Velocimetry, Michael P. Norconk

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

For a fluid dynamics experimental flow measurement technique, particle image velocimetry (PIV) provides significant advantages over other measurement techniques in its field. In contrast to temperature and pressure based probe measurements or other laser diagnostic techniques including laser Doppler velocimetry (LDV) and phase Doppler particle analysis (PDPA), PIV is unique due to its whole field measurement capability, non-intrusive nature, and ability to collect a vast amount of experimental data in a short time frame providing both quantitative and qualitative insight. These properties make PIV a desirable measurement technique for studies encompassing a broad range of fluid dynamics applications. However, as …

Me-Em 2011 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

• ME-EM: 85 Years of Excellence
• Faculty & Staff
• Enrollment & Degrees
• Alumni
• Resources
• Graduates

Wind Energy Potential For Reverse Osmosis Desalination Plants In La Guajira, Colombia, Carlos Martinez-Smit

Faculty-Selected Student Works

Project report required by the Master of Science Degree in Renewable and Clean Energy.

Abstract:

The region of La Guajira, located in the north of Colombia, has a lot of potential for wind power with annual average wind speeds up to 11 m/s at 10 m height in some locations, according to the national wind map. Most of the wind potential is located in Upper Guajira, where 90% of the population is indigenous Wayuu people (among the country’s poorest population) and it is also characterized with low precipitation, 500 mm/yr, high evapotranspiration, 1500 mm/yr, and low humidity. All this creates …

Evolution Of Natural History Information In The 21st Century – Developing An Integrated Framework For Biological And Geographical Data, Deborah A. Reusser, Henry Lee Ii

United States Environmental Protection Agency: Publications

Threats to marine and estuarine species operate over many spatial scales, from nutrient enrichment at the watershed/estuarine scale to invasive species and climate change at regional and global scales. To help address research questions across these scales, we provide here a standardized framework for a biogeographical information system containing queriable biological data that allows extraction of information on multiple species, across a variety of spatial scales based on species distributions, natural history attributes and habitat requirements. As scientists shift from research on localized impacts on individual species to regional and global scale threats, macroecological approaches of studying multiple species over …

Environmental Study Of Solid Waste Collection, Mousa Awad Maimoun

Electronic Theses and Dissertations

The growing municipal solid waste generation rates have necessitated more efficient, optimized waste collection facilities. The majority of the US collection fleet is composed of diesel-fueled vehicles which contribute significant atmospheric emissions including greenhouse gases. In order to reduce emissions to the atmosphere, more collection agencies are investigating alternative fuel technologies such as natural gas, biofuels (bio-gas and bio-diesel), and hybrid electric technology. This research is an in-depth environmental analysis of potential alternative fuel technologies for waste collection vehicles. This study will evaluate the use of alternative fuels by waste collection vehicles. Lifecycle emissions, cost, fuel and energy consumption were …

The Leachability Of Major Elements At Different Stages Of Weathering In Dry Disposed Coal Fly Ash, S.A. Akinyemi, A. Akinlua, W.M. Gitari, R.O. Akinyeye, L.F. Petrik

Coal Combustion and Gasification Products Journal Archive

Large quantities of solid residue are generated by coal-fired power stations in many parts of the World. The disposal and management of the unused fly ash remains a major problem to the environment. The weathered dry disposed ash cores comprise of major element constituents such as Al, Si, Ca, Mg, Fe, Mn, Na+ and K+. The mobility patterns and mineralogical associations of major elements in weathered dry disposed ash dumps aged 1-year-old, 8-year-old and 20-year-old from a coalfired power station in South Africa were investigated using a modified sequential extraction scheme. The extraction sequence was as follows: (1) water soluble, …

Waste Paper Generation In University Of Malaya., Poopak Sotoodehnia

Student Works (2010-2019)

The average global paper production growth was 4% annually. However, in some dynamic region such as China, this amount exceeded 8% in the last decade. Total production capacity of Malaysian paper mill reached 1.3 million tonnes/year while the consumption of paper is more than the production capacity. In Kuala Lumpur, the capital city of Malaysia, the second most abundant component of Municipal Solid Waste (MSW) is paper. Paper and pulp sector are one of the main consumers of fibrous wood resources which, has significant impact on the climate change by effecting forest resources. University of Malaya as an academic institute …

Techno-Economic Analysis And Engineering Design Consideration Of Algal Biofuel In Southern Nevada, Jian Ma

Mechanical Engineering Faculty Research

As the biological and chemical technologies in algae biofuels production, engineering design, siting and resources are playing some dominant role in successfully developing and scaling locally. The southwest region in U.S. has been identified by DoE and the USDA as the most suitable area for developing algal biofuel production due to several merits like the high level of solar radiation, large arid land not good for food production. Among this region, Southern Nevada has unique advantage to grow microalgae biomass, which is the large amount of CO2 emission from about 16 power plants in Clark County to support the world …

Hrc Enews — 2011 Winter, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

Retrieval Of Canopy Height Using Moderate-Resolution Imaging Spectroradiometer (Modis) Data, Zhuosen Wang, Crystal B. Schaaf, Philip Lewis, Yuri Knyazikhin, Mitchell A. Schull, Alan H. Strahler, Tian Yao, Ranga B. Myneni, Mark J. Chopping, Bryan J. Blair

United States National Aeronautics and Space Administration: Publications

In this study we use the 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) Bidirectional Reflectance Distribution Function (BRDF) product to develop multivariate linear regression models that estimate canopy heights over study sites at Howland Forest, Maine, Harvard Forest, Massachusetts and La Selva Forest, Costa Rica using (1) directional escape probabilities that are spectrally independent and (2) the directional spectral reflectances used to derive the directional escape probabilities. These measures of canopy architecture are compared with canopy height information retrieved from the airborne Laser Vegetation Imaging Sensor (LVIS). Both the escape probability and the directional reflectance approaches achieve good results, with …

Estimating Industrial Building Energy Savings Using Inverse Simulation, Franc Server, J. Kelly Kissock, Dan Brown, Steve Mulqueen

Mechanical and Aerospace Engineering Faculty Publications

Estimating energy savings from retrofitting existing building systems is traditionally a time intensive process, accomplished by developing a detailed building simulation model, running the model with actual weather data, calibrating the model to actual energy use data, modifying the model to include the proposed changes, then running the base and proposed models with typical weather data to estimate typical energy savings. This paper describes a less time-intensive method of estimating energy savings in industrial buildings using actual monthly energy consumption and weather data. The method begins by developing a multivariate three-parameter changepoint regression model of facility energy use. Next, the …

A Multicriteria Based Quantitative Framework For Assessing Sustainability Of Pile Foundations, Aditi Misra

Master's Theses

ABSTRACT

Civil Engineering is the major instrument of anthropocentric development over centuries through ever expanding infrastructure, cities and facilities.  Civil engineering processes are both resource and fuel intensive.  The building industry alone, during the construction stage, uses about 30-40% of the total resources used in the industrialized countries.  There is a growing consensus that delivering a sustainable built environment starts with incorporating sustainability thoughts at the planning and design stages of a project.  Geotechnical engineering is most resource intensive although this intensive consumption of energy goes unnoticed mainly because of the indirect nature of the energy used in the …

Sustainable Practices And Related Performance Measures At State Highway Agencies, Lenahan O’Connell

Kentucky Transportation Center Research Report

This report identifies seven ways in which an SHA can harm the environment: (1) excessive consumption of virgin materials; (2) unnecessary levels or amounts of storm water runoff; (3) release of environmental contaminants by SHA employees and contractors; (4) inadequate environmental training of employees and contractors; (5) wasteful use of energy by SHA employees and contractors; (6) the promotion of excessive driving by the public and concomitant release of green house gases; and (7) inadequate oversight mechanisms and procedures to prevent unsustainable practices. The report then identifies the sustainable practices and related performance measures SHAs can use to prevent or …