Engineering Commons^™

Model Fusion: A New Approach To Processing Heterogeneous Data, Omar Ochoa

Open Access Theses & Dissertations

In many practical situations, it is necessary to extract

information from data of different types. For example, in geosciences, several sources of data can be used to determine the interior structure of the earth: the first arriving waves from earthquakes and from man-made sources, measurements of the earth's gravity field, measurements of the dispersion of surface waves generated by earthquakes, etc. At present, most existing data processing techniques deal only with data of one type.

A joint use of all the information derived from multiple types of data sources is an important theoretical and practical challenge. Such a joint use …

Investigation Into The Operation And Safety Of Freeway Auxiliary Lanes: Towards Uniform Design Guidelines, Yubian Wang

Open Access Theses & Dissertations

Freeways operate closest to the purest form of uninterrupted traffic flow. There is no constant interruption to traffic flow (such as stop sign and traffic signal), and access is limited to ramp locations. Therefore, at freeways, bottlenecks, if exist, are usually caused by merging and diverging traffic at ramp locations. Bottleneck removal at freeway ramp areas can reduce average freeway commuter delay. Currently, engineers may add auxiliary lanes at ramp areas to mitigate or remove bottlenecks.

The American Association of State Highway Transportation Officials (AASHTO) publication A Policy on Geometric Design of Highways and Streets, commonly known as the "Green …

A Method To Reduce Plastic Shrinkage Cracking Of Concrete Using Re-Vibration Technique, Mustafa Abushaala Aldalinsi

Open Access Theses & Dissertations

One of the problems that reduce durability; thus, performance of concrete is the development of plastic shrinkage cracking (PSC). Traditionally, the development of PSC has been minimized by controlling its exposure to weather conditions or by adding fibers. In this study, concrete re-vibration was used as an alternative technique to control PSC because of the limited availability of fibers in the developing countries. In this study, the wait time after slab casting and before vibration was selected to be 90 minutes while length of re-vibration time was varied from 15 to 45 seconds. Also, the water-cement ratios were selected to …

Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano

Open Access Theses & Dissertations

Glucocorticoids are a class of steroid hormones that can either be produced synthetically or naturally by the adrenal glands. The synthetic glucocorticoids are highly prescribed in the United States for their anti-inflammatory and immunosuppressive properties to treat a variety of ailments and diseases; however, these have been implicated in a number of adverse human conditions such as obesity, metabolic syndrome, immune-suppression, delayed puberty, adrenal insufficiency and Cushing Syndrome, among others. Ongoing research has shown that synthetic and natural hormones are transported to aquatic environments via mammalian excretion or wastewater effluent, and as a result, the release of glucocorticoids into the …

Experimental Study On The Fabrication Of Advanced Materials For Energy Applications Using High Energy Mechanical Milling, Ashvin Kumar Narayana Swamy

Open Access Theses & Dissertations

The reaction of aluminum (Al) powder with water has the potential for on demand hydrogen generation. Conventional Al powders, however, react with water slowly due to a highly protective oxide layer on the particle surface. Current methods for Al activation involve harmful and expensive materials. The nano-scale Al powders also remain very expensive and have problems such as a large amount of oxide on the surface. The use of aluminum in an energy generation cycle is also hindered by the fact that, although Al is the most abundant metal in the Earth's crust, its recovery from ore consumes a lot …

Analysis Of Vehicle Interactions On Interstate Highways: Discrete Choice And Linear System Approaches, Alicia Romo

Open Access Theses & Dissertations

The research in this dissertation developed statistical and linear system models to predict driving behavior according to driver attributes, vehicle characteristics, car-following dynamics and/or driving conditions. The scope of this research was limited to the interaction of two vehicles traveling in the same direction on interstate highways.

The statistical models proposed in this research investigated the contributions of the different vehicle types on the manner and likelihood of collision. Discrete choice models were used to estimate the probability of the types of collision (rear-end, angle and sideswipe) as functions of driver attributes, striking and struck vehicle types, pre-crash driving actions …

A Hybrid Modelling Approach For Maintenance And Rehabilitation Treatment Effectiveness Of Asphalt Pavements In Texas, Daniel Saenz

Open Access Theses & Dissertations

Analysis tools in pavement management systems are critical to assist transportation agencies in developing the most adequate maintenance and rehabilitation program. The significant elements are not only the type of treatment selected and its cost, but also the quantification of its short-term and long-term effectiveness and the timing of intervention. Methodologies with complex statistical approaches and performance model theories have been previously implemented in their derivation, but they may not be suitable or accurate. Therefore, it is imperative to factor in engineering experience in their assessment. In this thesis, a hybrid modelling approach was presented to systematically introduce expert knowledge …

Synthetic Asphaltene As A Novel Dye In Dye Sensitized Solar Cells Dsscs, Hassan Sharif

Open Access Theses & Dissertations

This dissertation approves the possibility of the first time use of synthetic asphaltene as new dye in dye sensitized solar cells. In which the conversion efficiency of synthetic asphaltene DSSC has improved up to 2.0 %. Synthetic asphaltene sample was prepared from the starting material as in literature and applied for various solar cell parameters of TiO2 based dyesensitized solar cell DSSC. DSSCs were fabricated using the synthetic asphaltene as dye. Different variables and parameters were carried out to test the photovoltaic performance of the cells, these parameters include open-circuit voltage, short-circuit current; fill factor. The first result was obtained …

Adsorption Of Arsenic, Chromium, And Uranium From Saline Water On Clinoptilolite And The Treatment Of The Spent Regenerant By Duffusion Dialysis, Mutiu Olaitan Tanimola

Open Access Theses & Dissertations

Among various water purification and recycling technologies, adsorption is a fast, inexpensive and universal method. The development of low-cost adsorbents has led to the rapid growth of research interests in this field. The objective of this present study is the optimization of process parameters in adsorption of arsenic, chromium and uranium ions. The adsorption behavior of natural zeolite (clinoptilolite) has been studied in order to determine its applicability in treating water containing arsenic, chromium and uranium. The multiple adsorption of arsenic As (V), trivalent chromium Cr (III)] and uranium (VI) on natural zeolite (clinoptilolite) in single component and multiple component …

Evaluation Of Novel Backwashable Cartridge Filters: Efficacy And Sustainability, Michelle Brown

Open Access Theses & Dissertations

One of the important aspects of desalination pre–treatment is the removal of particles from feedwater. This is typically accomplished using a combination of gross filtration and cartridge filtration. Cartridge filters are typically single–use products, and their replacement can represent a significant portion of a desalination plant's operating budget. This research evaluated the performance of a new type of cartridge filter that is backwashable and aims to reduce the overall cost to desalination facilities and provide cleaner water. Two sets of filters were evaluated (in triplicate) with respect to particle removal efficiency and hydraulic efficiency. The initial set included four types …

An Evaluation Of The Cerro Process As An Efficient Ro Concentrate Management System, Guillermo Guadalupe Delgado

Open Access Theses & Dissertations

The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) Process is a new method to treat RO concentrate and brackish water with high concentrations of silica and calcium sulfate. Prior investigations have shown that the CERRO process can treat this kind of water without fouling or scaling the membranes, but the main factors that allow the system to operate in such conditions were not studied. The research presented here is an evaluation of the CERRO process as an efficient RO concentrate management system. The parameters of operation of the system were evaluated and improved. The precipitation of calcium sulfate was identified as …

Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob

Open Access Theses & Dissertations

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This Dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and …

Urban Impact Of Dissolved Metals In The Paso Del Norte Segment Of The Rio Grande, Sumayeh Ahmad Freiwan

Open Access Theses & Dissertations

The Paso del Norte segment of the Rio Grande experiences two seasons per year; the (wet) irrigation season and the (dry) non-irrigation season. The goal of this study was to improve the understanding of occurrence and contribution of dissolved metals in this region during the non-irrigation season. The objectives of this study were to (1) evaluate the impact of anthropogenic sources of metals on the Rio Grande water quality during the non-irrigation season, and (2) estimate the metal loads carried by the flow to the downstream region of El Paso. In order to evaluate the surface water quality of the …

Attitude Towards Green Warehousing In El Paso, Texas: An Exploratory Analysis, Lynda Jeanette Macias

Open Access Theses & Dissertations

The increasing reliance on fossil fuels by today's emerging economies has a profound implication on the sustainability of many warehousing and distribution logistical systems worldwide. This research attempts to fill the gap in current green warehousing literature by investigating how warehousing and distribution facilities view greener strategies as a way to increase operation efficiency through a stated preference approach. A survey instrument was developed, and the survey was conducted to identify warehousing characteristics, green practices, and current green views of warehouse managers in El Paso, Texas. The survey results found a balanced outlook within the environment and business needs. Companies …

Characterization Of Particulate Matter Concentrations (Pm10, Pm10-2.5, And Pm2.5) At High-Altitude School And Residential Mircroenvironments In Quito, Ecuador, Teresa Montoya

Open Access Theses & Dissertations

Air quality issues in Latin American countries are especially challenging because of the limited availability of resources to address them, lack of stringent standards and the rapid and uncontrolled growth of their cities increasing the number of vehicles on the road and the expansion of the industry. In particular, the city of Quito, Ecuador exacerbates its environmental issues by its high-altitude (2800 m above sea level) coupled by its location around a mountain valley and frequent temperature inversions.

This study focused on evaluating the spatial variation of the PM concentrations and the effectiveness of a central monitoring network in representing …

A Systematic Approach To Manage Missing Data In Pavement Management Systems, Mazin M. Al-Zou'bi

Open Access Theses & Dissertations

Pavements are an important part of the highway transportation infrastructure, accounting for the largest share of the overall investment. A tremendous amount of time and money is spent each year on the construction of new pavements, as well as on the maintenance and rehabilitation of existing pavements.

Transportation agencies use pavement management systems (PMS) for their maintenance and rehabilitation planning, programming, and budgeting. PMS are used to make decisions regarding when maintenance and rehabilitation should be applied. The systems also select what type of treatment should be applied for each pavement section in the network with clear estimations of the …

Optimization Of Stress Wave-Based Nondestructive Methods In Identifying Deterioration In Concrete Structures, Hoda Azari

Open Access Theses & Dissertations

The transportation infrastructure across the United States is deteriorating and requires periodic inspection to predict the cost of repair and extent of maintenance activities, to remedy structural problems, and to ensure safety and serviceability. The use of nondestructive testing (NDT) methods in detecting and characterizing flaws in the infrastructure has become more common. Among different NDT methods, the stress wave-based methods, including ultrasonic surface waves (USW) and impact echo (IE) methods, are widely used to maintain concrete structures. In this dissertation, a complete literature review of seismic wave theory and wave propagation in plate like structures, and stress wave-based methods …

The Investigation Of The Practice Of Frugal Innovation Across Cultures And The Introduction Of An Instructional Model For Streamlining The Design Process, Andres Efren Bolanos

Open Access Theses & Dissertations

The central objectives of this dissertation are to analyze frugal innovation, apply foundational methodologies that contribute to product design, and discover the important contextual information for successful development. This dissertation describes a systematic procedure in designing frugally innovated products. The institutional design will encompass environmental, social, and economic impacts into the entire products' life cycle. Also, a comparison is made between two developing nations' contextual factors to reveal the formulation of frugal innovation.

Geochemical Characterization Of Mineral Dust Sources In The Chihuahuan Desert And Southern High Plains Regions, Porfirio Peinado

Open Access Theses & Dissertations

The Chihuahuan Desert (northern Chihuahua, southern New Mexico, and far west Texas) and the southern High Plains (west Texas and eastern New Mexico) regions have been identified as one of the most persistent dust producing regions of North America. Regional-scale dust storms have been observed by satellite imagery to identify sources of dust, resulting in collection and examination of physical soil samples to better understand the source signatures (geochemical characteristics) of dust origins in these two regions.

The soil characteristics were examined through several techniques: Particle Size Distribution, X-Ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), and Total …

Purification Of Sodium Sulfate By Crystallization, Perla Teresita Torres

Open Access Theses & Dissertations

Sodium sulfate can be recovered from a dilute solution by concentrating it by conventional water treatment techniques like reverse osmosis and electrodialysis; however, those processes also concentrate impurities like arsenic. The sodium sulfate would have commercial use if it can be recovered in an arsenic-free form. This study demonstrated that sodium sulfate could be separated from impurities using slow cooling crystallization in a novel apparatus developed and designed during the experimentation. This device is called a heat exchanger crystallizer and allows slow cooling crystallization in order to grow pure crystals of sodium sulfate decahydrate. Crystals grown in the heat exchanger …

Recovering Magnesium Hydroxide And Sodium Chloride From Zero Discharge Desalination Concentrate Streams, Alemayehu Asfaw Yetayew

Open Access Theses & Dissertations

UTEP and Veolia Water Solutions & Technologies have been demonstrating and commercializing the Zero Discharge Desalination (ZDD) technology as part of a three year project sponsored by the U.S. Bureau of Reclamation. ZDD is able to achieve up to 98% recovery by desalinating brackish groundwater. ZDD is typically comprised of a reverse osmosis (RO) or nanofiltration (NF) system and a unique variation of electrodialysis called electrodialysis metathesis (EDM). The ZDD technology increases the yield of fresh water from water supplies that contain enough CaSO4 to cause precipitation problems when the water is treated with RO or NF alone. The EDM …