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2019

Civil and Environmental Engineering

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Articles 1 - 30 of 1716

Full-Text Articles in Engineering

Remediating Soil For Successful Vegetation Establishment Along Nebraska Highways, Shad Mills, Martha Mamo, Walt Schacht, Humberto Blanco-Canqui Dec 2019

Remediating Soil For Successful Vegetation Establishment Along Nebraska Highways, Shad Mills, Martha Mamo, Walt Schacht, Humberto Blanco-Canqui

Nebraska Department of Transportation Research Reports

Vegetation along roadsides is important to prevent soil erosion, provide habitat, and filter water running off the road. Vegetation close to the pavement along highways in Nebraska does not readily establish and persist. It is thought that the sodium and bulk density are the driving factors behind the lack of vegetation. After a construction project the shoulder is seeded into the compacted soil, and during winter salts can accumulate in the soil because of deicing agents being used. The purpose of our study was to determine if the sodium and bulk density are the driving factors of the vegetation cover ...


Establishment Of Wildflower Islands To Enhance Roadside Health And Aesthetics, Walter Schacht, Judy Wu-Smart Dec 2019

Establishment Of Wildflower Islands To Enhance Roadside Health And Aesthetics, Walter Schacht, Judy Wu-Smart

Nebraska Department of Transportation Research Reports

Wildflowers are crucial in the ecological function of the low-input roadside plant communities in terms of water andnutrient cycling, nutrient inputs such as nitrogen, total plant canopy cover, stand longevity, and provision of habitat for numerous small animals. Further, wildflowers provide critical foraging and nesting resources for birds, insects, and other wildlife. Unfortunately, habitat loss from agricultural and urban development has led to rapid population declines in wild bees and other pollinators across the US, thereby jeopardizing not only food production but also the sustainability of our natural landscapes (Kearns & Inouye, 1997). One way to mitigate wild bee decline is ...


Assessment Of Groundwater Resources In Siwa Oasis, Western Desert, Egypt, Noha H. Moghazy, Jagath J. Kaluarachchi Dec 2019

Assessment Of Groundwater Resources In Siwa Oasis, Western Desert, Egypt, Noha H. Moghazy, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

One of the major challenges facing Egypt is limited water resources associated with rapid increase in population. In 1960s, Egyptian government started to use groundwater from the Nubian Sandstone Aquifer System (NSAS) in the Western Desert to expand agricultural sector. Siwa Oasis is the focus of this study to assess the efficiency of groundwater use and corresponding impacts from 1980 to 2012. Results show that from 1980 to 1998, withdrawal from poorly designed wells increased rapidly causing an increase in excess water about 336%. The increase of excess water with the usage of poor drainage produced lakes. Remote Sensing showed ...


Evaluation Of The Mechanisms And Effectiveness Of Nano-Hydroxides, Wood And Dairy Manure-Derived Biochars To Remove Fluoride And Heavy Metals From Water, Anna Rose Wallace, Wenjie Sun Dr, Chunming Su Dr Dec 2019

Evaluation Of The Mechanisms And Effectiveness Of Nano-Hydroxides, Wood And Dairy Manure-Derived Biochars To Remove Fluoride And Heavy Metals From Water, Anna Rose Wallace, Wenjie Sun Dr, Chunming Su Dr

Civil and Environmental Engineering Theses and Dissertations

The development of effective treatment processes for the removal contaminants, such as fluoride and heavy metals, from polluted water have been urgently needed due to serious environmental health and safety concerns. In this dissertation, a variety of materials including various (hydro)oxide nanomaterials, biochars and surface modified biochar were studied to evaluate their effectiveness and mechanism on removing fluoride or mixed heavy metals from water.

In the Chapter 2, this study investigated the adsorptive removal of fluoride from water using various (hydro)oxide nanomaterials, focusing on ferrihydrite, hydroxyapatite (HAP) and brucite, which have the potential to be used as sorbents ...


Removel Of Polluntants From Aqueous Solution Via Graphene Oxide/Magnesium Oxide Nanocomposites, Mahdi Heidarizad Dec 2019

Removel Of Polluntants From Aqueous Solution Via Graphene Oxide/Magnesium Oxide Nanocomposites, Mahdi Heidarizad

Civil and Environmental Engineering Theses and Dissertations

In this study, a series of graphene oxide/magnesium oxide nanocomposites (GO/MgO NCs) were synthesized and applied for the removal of Methylene Blue (MB) from aqueous solutions. The prepared NCs were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The results showed that MgO particles were successfully layered on GO. The impacts of different experimental variables on the removal of MB including GO/MgO NCs dosage, pH, contact time, and initial MB concentration were investigated.

Thereafter, we investigate the mechanism and kinetics of ozonation processes in the presence of GO/MgO ...


Incorporation Of Unmanned Aerial Vehicle (Uav) Point Cloud Products Into Remote Sensing Evapotranspiration Models, Mahyar Aboutalebi, Alfonso F. Torres-Rua, Mac Mckee, William P. Kustas, Héctor Nieto, Maria Mar Alsina, Alex White, John H. Prueger, Lynn Mckee, Joseph Alfieri, Lawrence E. Hipps, Calvin Coopmans, Nick Dokoozlian Dec 2019

Incorporation Of Unmanned Aerial Vehicle (Uav) Point Cloud Products Into Remote Sensing Evapotranspiration Models, Mahyar Aboutalebi, Alfonso F. Torres-Rua, Mac Mckee, William P. Kustas, Héctor Nieto, Maria Mar Alsina, Alex White, John H. Prueger, Lynn Mckee, Joseph Alfieri, Lawrence E. Hipps, Calvin Coopmans, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

In recent years, the deployment of satellites and unmanned aerial vehicles (UAVs) has led to production of enormous amounts of data and to novel data processing and analysis techniques for monitoring crop conditions. One overlooked data source amid these efforts, however, is incorporation of 3D information derived from multi-spectral imagery and photogrammetry algorithms into crop monitoring algorithms. Few studies and algorithms have taken advantage of 3D UAV information in monitoring and assessment of plant conditions. In this study, different aspects of UAV point cloud information for enhancing remote sensing evapotranspiration (ET) models, particularly the Two-Source Energy Balance Model (TSEB), over ...


Two Clamped Pipe Support Connections For Oil And Gas Brownfield Projects, Helen M. Claycomb Dec 2019

Two Clamped Pipe Support Connections For Oil And Gas Brownfield Projects, Helen M. Claycomb

University of New Orleans Theses and Dissertations

In the oil and gas industry, brownfield projects focus on the modification of or addition to an existing production facility that is fully operational and operating. Welding is typically avoided on these projects. The drilling of holes in existing primary structural elements is also prohibited. Clamped connections are often used when adding additional services in a brownfield project. There are different types of clamped connections utilized when a new structural support must be attached to an existing vertical structural pipe. The short bolt clamped connection is a well-established connection and typically used on offshore projects. The U-bolt clamped connection is ...


A Laboratory Investigation Of Cement Based Materials With Cellulose Nanofibers, Parivash Takasi Dec 2019

A Laboratory Investigation Of Cement Based Materials With Cellulose Nanofibers, Parivash Takasi

Electronic Theses and Dissertations

Cellulose Nanofibers (CNFs) are used as additives in cement-based products to modify their properties. Recent studies about the effects of CNFs on cement paste showed inconsistent results for several different important properties, including compressive strength and free shrinkage. There is reason to believe that the unsystematic results of the compressive strengths were affected by the lack of uniform dispersion of CNFs. As a potential remedy, two different mixing methods were applied. The first method used a basic mixer, but aggregates were added to the cement paste mixture to improve the blending process. The second method utilized a high-speed shear mixer ...


Wintertime Spatial Distribution Of Ammonia And Its Emission Sources In The Great Salt Lake Region, Alexander Moravek, Jennifer G. Murphy, Amy Hrdina, John C. Lin, Christopher Pennell, Alessandro Franchin, Ann M. Middlebrook, Dorothy L. Fibiger, Caroline C. Womack, Erin E. Mcduffie, Randy S. Martin, Kori D. Moore, Munkhbayar Baasandorj, Steven S. Brown Dec 2019

Wintertime Spatial Distribution Of Ammonia And Its Emission Sources In The Great Salt Lake Region, Alexander Moravek, Jennifer G. Murphy, Amy Hrdina, John C. Lin, Christopher Pennell, Alessandro Franchin, Ann M. Middlebrook, Dorothy L. Fibiger, Caroline C. Womack, Erin E. Mcduffie, Randy S. Martin, Kori D. Moore, Munkhbayar Baasandorj, Steven S. Brown

Civil and Environmental Engineering Faculty Publications

Ammonium-containing aerosols are a major component of wintertime air pollution in many densely populated regions around the world. Especially in mountain basins, the formation of persistent cold-air pools (PCAPs) can enhance particulate matter with diameters less than 2.5 µm (PM2.5) to levels above air quality standards. Under these conditions, PM2.5 in the Great Salt Lake region of northern Utah has been shown to be primarily composed of ammonium nitrate; however, its formation processes and sources of its precursors are not fully understood. Hence, it is key to understanding the emission sources of its gas phase ...


An Investigation On The Effects Of Cellulose Nanofibrils On The Performance Of Cement Based Composites, Hosain Haddad Kolour Dec 2019

An Investigation On The Effects Of Cellulose Nanofibrils On The Performance Of Cement Based Composites, Hosain Haddad Kolour

Electronic Theses and Dissertations

Cellulose nanofibrils (CNFs) are hydrophilic biodegradable nanoparticles (typically, less than 0.2 mm in length and 20-50 nm in width) that can be extracted from various plants, trees, and recycled paper stock. Their low density, low toxicity, relatively low cost, high aspect ratio, and high specific surface enable functionalization. In this work, the effects of CNFs on selected properties of cement paste, mortar, and concrete were investigated. For the cement pastes, rheology tests using a simple rheometer showed a reduction in workability as CNF dosage increased. Free shrinkage tests showed an increase in shrinkage at high w/c ratios but ...


Effect Of Recycled Concrete Aggregates On The Long-Term, Elastic, Total Deflection And Strength Of Precast Prestressed Hollow Core Concrete Slabs, Lizeth Marisol Gomez Santana Dec 2019

Effect Of Recycled Concrete Aggregates On The Long-Term, Elastic, Total Deflection And Strength Of Precast Prestressed Hollow Core Concrete Slabs, Lizeth Marisol Gomez Santana

Civil Engineering Theses

Concrete constitutes the largest portion of construction and demolition waste generated each year in the United States. The Environmental Protection Agency (EPA) estimates that the total production of construction and demolition of concrete waste during 2015 was 381.8 million tons. In order to reduce the economic and environmental effects of waste concrete, researchers have begun to incorporate it into concrete mixtures. However, the inherent variability in mechanical properties between RCA sources makes it difficult to quantify the maximum permissible replacement of natural aggregate and the end-result properties of concrete. This project investigates the use of recycled concrete aggregates (RCA ...


An Analysis Of Energy Consumption And The Use Of Renewables For A Small Drinking Water Treatment Plant, Saria Bukhary, Jacimara Batista, Sajjad Ahmad Dec 2019

An Analysis Of Energy Consumption And The Use Of Renewables For A Small Drinking Water Treatment Plant, Saria Bukhary, Jacimara Batista, Sajjad Ahmad

Civil & Environmental Engineering and Construction Faculty Publications

One of the pressing issues currently faced by the water industry is incorporating sustainability considerations into design practice and reducing the carbon emissions of energy-intensive processes. Water treatment, an indispensable step for safeguarding public health, is an energy-intensive process. The purpose of this study was to analyze the energy consumption of an existing drinking water treatment plant (DWTP), then conduct a modeling study for using photovoltaics (PVs) to offset that energy consumption, and thus reduce emissions. The selected plant, located in southwestern United States, treats 0.425 m3 of groundwater per second by utilizing the processes of coagulation, filtration, and ...


Rheological Models For Non-Newtonian Viscosity Of Modified Asphalt Binders And Mastics, Aboelkasim Diab, Zhanping You, Xuelian Li, Jorge Carvalho Pais, Xu Yang, Siyu Chen Dec 2019

Rheological Models For Non-Newtonian Viscosity Of Modified Asphalt Binders And Mastics, Aboelkasim Diab, Zhanping You, Xuelian Li, Jorge Carvalho Pais, Xu Yang, Siyu Chen

Michigan Tech Publications

This paper is aimed at providing a comprehensive experimental work on the viscosity behavior of different modified asphalt binders and mastics, as well as exploring mathematical representations of the results in attempts to predict the viscosity and flow behaviors according to Vinogradov-Malkin and Phillips-Deutsch models. The modified asphalt binders were prepared in the unaged and aged states using styrene-butadienestyrene (SBS), ethylene-vinyl acetate (EVA), and crumb rubber (CR); while the hydrated lime (HL) and fly ash (FA) were selected to produce the binder-filler mastics. To widen the study findings, the additives (polymers, rubber, and fillers) were applied at different possible levels ...


Strengthening Of Corroded Steel Structures Using Cfrp – An Experimental Review, Ghada El-Mahdy Ph.D., P.Eng, Abdallah H. Yassin, Abdel El Rahman Khaled Dec 2019

Strengthening Of Corroded Steel Structures Using Cfrp – An Experimental Review, Ghada El-Mahdy Ph.D., P.Eng, Abdallah H. Yassin, Abdel El Rahman Khaled

Civil Engineering

Fibre reinforced polymers (FRP) have been widely used to strengthen reinforced concrete structures, however, nowadays their use to strengthen steel structures is under investigation. In particular, the need to strengthen corroded steel structures found in aggressive environments, such as marine environments, which have undergone a reduction in cross-sectional area and hence a reduction in their load-carrying capacity is in need of studying. The main problems that arise when using carbon fibre reinforced polymer (CFRP) sheets to strengthen steel structures is the weakness in the interfacial bond between the CFRP and the steel surface, the thinness of CFRP sheet, and the ...


Sway And No-Sway Behaviour Of Pitched Roof Portal Frames Composed Of Cold-Formed Steel Sections, Ghada El-Mahdy Ph.D, P.Eng., Maged Tawfick Hanna Ph.D Dec 2019

Sway And No-Sway Behaviour Of Pitched Roof Portal Frames Composed Of Cold-Formed Steel Sections, Ghada El-Mahdy Ph.D, P.Eng., Maged Tawfick Hanna Ph.D

Civil Engineering

Cold-formed sections buckle locally and distortionally in combination with overall buckling of the member. When these sections are incorporated into a portal frame structure, this combination of buckling modes affects the overall buckling behaviour of the portal frame. The objective of this paper is to study the effect of local and distortional buckling on the overall behaviour of portal frames. The portal frames studied have a span of 10 m and an eave height of 3 m with a roof pitch of 1:10. Two frames are studied the first with one intermediate interconnector at the midpoints of the column ...


Partial Nitritation Anammox Process For Sidestream Wastewater Treatment In Mabr Technology, Panagiota Stamatopoulou Dec 2019

Partial Nitritation Anammox Process For Sidestream Wastewater Treatment In Mabr Technology, Panagiota Stamatopoulou

Electronic Thesis and Dissertation Repository

There has been an increased interest in alternative wastewater treatment systems to improve nutrients removal and energy consumptions while achieving acceptable discharge limits. Wastewater treatment plants (WWTP) have shifted their interest in treating the sidestream wastewater; a reject liquid post anaerobic digestion, rich in ammonium-nitrogen. A dedicated sidestream wastewater treatment unit has become an attractive option with the finding of a relatively new species of bacteria, anaerobic ammonium oxidizers (anammox), able to convert ammonium and nitrite into nitrogen gas. However, anammox bacteria are sensitive in environmental changes, and in combination with their low growth rate, it is challenging to establish ...


Anaerobic Digestion Modeling Of A High Rate Acidification Pre-Treatment Technology, Connor Pritty Dec 2019

Anaerobic Digestion Modeling Of A High Rate Acidification Pre-Treatment Technology, Connor Pritty

Electronic Thesis and Dissertation Repository

Through the application of a computerized model (BioWin), anaerobic co-digestion (AcoD) of source separated organics (SSO) and a high rate acidification technology (pretreatment) for a conventional wastewater treatment plant was reviewed. Through this combined approach of high rate acidification, and co-digestion techniques it was found that the experimental modeling scenarios offered increases when compared to the existing base scenario production levels. With the addition of the high rate acidification technology and application of source separated organics the maximum increases in biogas production came when an OLR of 5.24 kg-COD/m³/day and 97g COD/L/d was experimentally modeled ...


Evaluation Of A Novel Remote Displacement Sensor Prototype Using Video And Laser-Based Technology For Civil Infrastructure Applications, Nicholas J. Brown Dec 2019

Evaluation Of A Novel Remote Displacement Sensor Prototype Using Video And Laser-Based Technology For Civil Infrastructure Applications, Nicholas J. Brown

Civil and Environmental Engineering Master's Project Reports

Deflection measurements on structures, especially with regards to long-term monitoring, continues to be a challenge with current sensor technologies. Material degradation and changes in the mechanical properties due to aging (for example, creep and shrinkage in concrete bridges) directly impact the deflections exhibited by a structure. In this article we introduce and discuss the evaluation of a novel laser and video-based displacement sensor prototype to monitor displacements and rotations in structures remotely. The sensor is both inexpensive, using off-the shelf components, but also accurate and practical for situations that do not allow the use of conventional displacement sensors, which require ...


Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire Dec 2019

Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire

Dissertations and Theses

The Portland area has an extensive flood history since it was founded in 1845. In the late 19th century, the Portland area was prone to flooding from snowmelt freshets (3-6 months duration) and brief winter rain or rain-on-snow events. Since that time the magnitude of spring freshets has been curtailed by 45% due to climate change, flow diversions, and reservoir management. Along with changes in hydrology, the bathymetry of the Lower Columbia River has been altered by the dredging of the navigation channel, diking, and land reclamation. To understand how these changes in hydrology and bathymetry have affected tidal and ...


Contemporary Problems In Aerosol Aggregation And Gelation, Pai Liu Dec 2019

Contemporary Problems In Aerosol Aggregation And Gelation, Pai Liu

Engineering and Applied Science Theses & Dissertations

Aggregation of nanoparticles in aerosols is a fundamental phenomenon with important implications to diverse fields ranging from material synthesis to pollutant control. The past few decades have witnessed extensive research on investigating the structure and growth mechanism of aerosol aggregates with sizes spanning across several orders of magnitude. This dissertation focuses on some contemporary problems that remain unaddressed in this topical area. Aerosol aggregates in sub-micron regimes, which are formed via the irreversible collision and aggregation of solid nanoparticle monomers, are fractal-like in their morphology. A mathematical description of this seemingly random structure dates to the seminal works by Forest ...


Evaluation Of Titanosilicate Materials For The Sorption Of Cesium And Strontium From High Level Wastes, Matheus Tolentino Lauar Dec 2019

Evaluation Of Titanosilicate Materials For The Sorption Of Cesium And Strontium From High Level Wastes, Matheus Tolentino Lauar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Treatment of high-level waste (HLW) stored in the U.S. Department of Energy (U.S. DOE) sites of Hanford and Savannah River involves the separation of radioactive cesium (137Cs) and strontium (90Sr). Challenges in treating the liquid HLW includes high alkalinity or acidity, and high salt content, many orders of magnitude above Cs and Sr concentrations. Ion exchange is the preferred process for removing these compounds, due to the availability of selective media and large volume-processing capacity by column operations. The crystalline silicotitanate (Na2Ti2O3SiO4·2H2O), i.e. CST, which structure is analog to the mineral sitinakite, is considered the reference ...


Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier Dec 2019

Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this work was to evaluate the utility of bench scale sand tank experiments at assessing permeable reactive barrier (PRB) design. Our criteria for meeting this goal was that differences between PRB designs could be identified solely by measuring concentration in outflow from the sand tank models. For our PRB designs (funnel-and-gate, staggered wells, and parallel bars), numerical simulations clearly showed that PRB design had a quantifiable effect on outflow concentration, provided that the solute reacted with the PRB materials. Conversely, use of a conservative (non-reactive) solute did not allow us to discern between PRB design alternatives. Employing ...


Investigating Sources Of Selenium In Shallow Groundwater In The Las Vegas Valley, Sahar Ehsani Dec 2019

Investigating Sources Of Selenium In Shallow Groundwater In The Las Vegas Valley, Sahar Ehsani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Selenium concentrations above EPA safe levels are of potential concern in various parts of the Las Vegas Valley (Valley) in both water and sediment media. Previous studies suggest that the source of elevated selenium in the Valley is possibly resurfacing groundwater. Shallow groundwater flows into Las Vegas Wash wetlands, and therefore, it has important environmental implications as it affects the quality of tributaries and surface water. However, to date, there have not been any studies to determine the origins of selenium in Las Vegas Valley shallow groundwater. Identifying and understanding the source, spatial distribution and mobility of selenium regarding the ...


Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer Dec 2019

Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Structural health monitoring (SHM) of an instrumented structure provides numerous benefits when assessing the long-term condition of the structure against degradation, or the short-term condition after an extreme event, such as an earthquake. The Nevada Department of Transportation (NDOT) has an interest in expanding the use of SHM for such assessments. Accordingly, the objective of the current study is to develop and implement a permanent SHM system for the Galena Creek Bridge, the largest concrete cathedral arch bridge in the world, to monitor its response to routine traffic and seismic activity. Completed in 2012, the bridge connects Reno and Carson ...


Alkali-Silica Reactivity Of Mortars Containing Natural Pozzolan, Arash Kian Dec 2019

Alkali-Silica Reactivity Of Mortars Containing Natural Pozzolan, Arash Kian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali-silica reactivity is one of the most recognized deleterious phenomena in Portland cement concrete resulting in cracks, spalling, and other deleterious mechanisms.

The aim of this study was (i) to assess the extent of reactivity of the aggregates, quarried from seven different sources, suspected of being conducive to ASR, and (ii) to compare the effectiveness of industrial (Class F fly ash) and natural pozzolans in mitigation of alkali-silica reactivity of the studied aggregates. To this end, seven aggregate sources, four natural pozzolan sources, and one source of Class F fly ash were used. ASTM Type V Portland cement was replaced ...


Development Of Natural Perlite Based Concrete For Sustainable Construction, Seyedmahmoud Motaharikarein Dec 2019

Development Of Natural Perlite Based Concrete For Sustainable Construction, Seyedmahmoud Motaharikarein

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study aimed to partially replace Portland Cement (PC) with environmentally friendly binders capable of improving the longevity of concrete. The new binders consisted of different proportions of natural pozzolan (perlite) with various fineness and particle size distributions. A step-by-step research program was designed to: (1) discover the optimum fineness of perlite powder and its optimum replacement level with cement; (2) investigate the rheological properties of the perlite-containing mixtures, and examine whether this binder can be used in selfconsolidating concrete; and (3) assess the weaknesses of the new binder, and improve its deficiencies by using nanomaterials such as nano-silica. The ...


Treatment Of Perchlorate And Multiple Oxyanions: Chemical And Biological Investigations, Mark Elkouz Dec 2019

Treatment Of Perchlorate And Multiple Oxyanions: Chemical And Biological Investigations, Mark Elkouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater contamination with oxyanions is an issue that must be addressed for environmental, ecological and societal reasons. Chemical and biological treatment methods of reduction are already known and practiced, but the simultaneous presence of multiple oxyanions can add complicating effects to treatment sequence and efficacy. This research was concerned with the investigation of the chemical reductive treatment of Cr(VI) using both calcium polysulfide (CaSx) and ferrous sulfate (FeSO4), and the biological reductive treatment of chlorate, Cr(VI), nitrate and perchlorate using multiple organic substrates. The chemical treatment phase consisted of initial jar tests, using CaSx and FeSO4, followed by ...


Examining The Effectiveness Of A 4d Schedule And A Virtual Reality Model On A Modular Project: Unlv Solar Decathlon Case, Rajarshi Ghimire Dec 2019

Examining The Effectiveness Of A 4d Schedule And A Virtual Reality Model On A Modular Project: Unlv Solar Decathlon Case, Rajarshi Ghimire

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of a 4D schedule as technological advancement has brought significant improvement to the planning and execution of construction projects, through visualizing stepwise construction progress, following a sequence of pre-planned activities, and finalizing a baseline schedule with necessary changes. Moreover, the application of virtual reality (VR) to create interactive 3D models of a planned structure has made it possible to make a detailed planning of any construction project. Because of these benefits, the use of 4D schedules and VR in the construction industry has increased drastically, leading to improved planning and execution. However, past studies have given little attention ...


Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena Dec 2019

Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena

UNLV Theses, Dissertations, Professional Papers, and Capstones

The strategic planning objectives for a novel Bike Sharing Systems (BSS) are to locate the BSS stations, size the stations, and determine the bicycle fleet size, among others. Current guidelines to design BSS programs are tailored to city centers with large coverage areas and high bicycle to population ratios, and thus not directly transferable to a university setting. An ordered probit model was created using data from a university online stated preference survey to determine the key factors that affect the uptake rates for the UNLV BSS program and to estimate the potential demand. The demand analysis was incorporated into ...


Impact Of Design Cost Percentage On Cost Growth, Schedule Growth, And Construction Intensity Of Road Construction Projects, Elina Prajapati Dec 2019

Impact Of Design Cost Percentage On Cost Growth, Schedule Growth, And Construction Intensity Of Road Construction Projects, Elina Prajapati

UNLV Theses, Dissertations, Professional Papers, and Capstones

The performance of construction projects is measured in terms of cost and schedule variation. Studies have identified that such variations are mainly due to design changes, which are more frequent on projects executed through the design-bid-build (DBB) delivery method. Thus, the design factor is identified as one of the major parameters affecting the performance of DBB projects. Despite the majority of road projects being constructed following the DBB method, the impact of design cost on the performance of road projects has not been sufficiently studied yet. Therefore, this study focuses on determining the effect of design cost on the performance ...