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Full-Text Articles in Engineering

Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung May 2017

Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung

Theses and Dissertations

Cold in-place recycling (CIR) is a process that takes three to four inches of existing pavement surface and reuses 100% of it by milling and crushing it, adding asphalt emulsions and/or additives to it, before placing and re-compacting it. There is currently very little research regarding the interaction between the crushed aggregate and asphalt emulsion during the CIR process. In this study, the interactions between the combinations of crushed aggregates and asphalt emulsions were investigated along with select compaction metrics and a raveling performance test. The three types of aggregates included coated limestone, recycled asphalt pavement (RAP), and coated ...


Race, Class And Gender In Engineering Education: A Quantitative Investigation Of First Year Enrollment, Canek Moises Luna Phillips Dec 2016

Race, Class And Gender In Engineering Education: A Quantitative Investigation Of First Year Enrollment, Canek Moises Luna Phillips

Open Access Dissertations

Research explanations for the disparity across both race and gender in engineering education has typically relied on a deficit model, whereby women and people of color lack the requisite knowledge or psychological characteristics that Whites and men have to become engineers in sufficient numbers. Instead of using a deficit model approach to explain gender and race disparity, in the three studies conducted for this dissertation, I approach gender and race disparity as the result of processes of segregation linked to the historic and on-going perpetuation of systemic sources of oppression in the United States. In the first study, I investigate ...


A Unicorn's Tale: Examining The Experiences Of Black Women In Engineering Industry, Monique S. Ross Dec 2016

A Unicorn's Tale: Examining The Experiences Of Black Women In Engineering Industry, Monique S. Ross

Open Access Dissertations

Black women have recently been identified as the most educated demographic in the United States, and yet they are grossly underrepresented in engineering. They comprise 6.4 % of the U.S. population and only 0.72 % of engineering industry. Meanwhile, engineers have been identified as the key to the United States’ ability to maintain its prominence and leadership in a competitive global economy due to their contribution to maintaining and improving our infrastructures and standard of living. This significance to society has spawned national initiatives geared towards broadening participation in engineering. This research study was designed to explore the experiences ...


Identifying And Prioritizing Critical Success Factors For Fixed Base Operators In The United States: A Mixed Method Approach, Yu Wang Dec 2016

Identifying And Prioritizing Critical Success Factors For Fixed Base Operators In The United States: A Mixed Method Approach, Yu Wang

Open Access Dissertations

Fixed Base Operators (FBOs) are major service providers for the general aviation (GA) sector, which closely connect the public with the aviation industry. However, over the past decade, the U.S. GA industry has experienced a decline in the numbers of registered aircraft, pilots, and airports. Due to the fact that FBOs significantly contribute to the aviation industry, further research studies regarding the FBO-sector at a national level are needed. The purpose of this dissertation was to identify and prioritize the critical success factors (CSFs) that promote the success of FBO operations in the United States.

The methodology consisted of ...


Safety Performance Prediction Of Large-Truck Drivers In The Transportation Industry, Emily Moneka Francis Xavier Dec 2016

Safety Performance Prediction Of Large-Truck Drivers In The Transportation Industry, Emily Moneka Francis Xavier

Theses and Dissertations

The trucking industry and truck drivers play a key role in the United States commercial transportation sector. Accidents involving large trucks is one such big event that can cause huge problems to the driver, company, customer and other road users causing property damage and loss of life. The objective of this research is to concentrate on an individual transportation company and use their historical data to build models based on statistical and machine learning methods to predict accidents. The focus is to build models that has high accuracy and correctly predicts an accident. Logistic regression and penalized logistic regression models ...


Eveleth, Minnesota: A Portrait Of My Home Town, Judith I. Luna Dec 2016

Eveleth, Minnesota: A Portrait Of My Home Town, Judith I. Luna

Theses and Dissertations

This 30-minute documentary film provides snapshots of the small northeastern iron mining town of Eveleth, Minnesota, on the Mesabi Iron Range. It uses a two-pronged approach: 1) a first-person return to the town by the filmmaker almost 50 years after graduating from high school to see how the town may have changed, 2) a look at some historical and cultural factors which made the town what it was when the filmmaker was growing up and what continues to animate the town in the face of iron mining’s decline and rebirth. The latter include the immigrant experience and influence as ...


Modeling, Control, And Impact Analysis Of The Next Generation Transportation System, Feng Zhu Aug 2016

Modeling, Control, And Impact Analysis Of The Next Generation Transportation System, Feng Zhu

Open Access Dissertations

This dissertation aims to develop a systematic tool designated for connected and autonomous vehicles, integrating the simulation of traffic dynamics, traffic control strategies, and impact analysis at the network level.

The first part of the dissertation is devoted to the traffic flow modeling of connected vehicles. This task is the foundation step for transportation planning, optimized network design, efficient traffic control strategies, etc, of the next generation transportation system. Chapter 2 proposes a cell-based simulation approach to model the proactive driving behavior of connected vehicles. Firstly, a state variable of connected vehicle is introduced to track the trajectory of connected ...


A Mixed Methods Study On Choice Of Media Influence On Construction Industry Communication, Luciana De Cresce El Debs Aug 2016

A Mixed Methods Study On Choice Of Media Influence On Construction Industry Communication, Luciana De Cresce El Debs

Open Access Dissertations

This study focuses on the use of different communication media for solving problems in the construction industry. The focus of this research is on design-problems containing spatial information and are informally reported between site supervision and design professionals. Due to the fragmented nature of the construction industry, miscommunication is a well-known and common problem. Yet, this fragmented nature is necessary in order to build a complex product involving many different types of professionals. To better understand the issue, this study uses previous literature, such as those published on media richness theory, problem-solving strategy, and construction specific communications, in a three-phased ...


Enabling A Sustainable Economy Through Energy Systems Modeling: Solar-Centric, Efficient, Integrated And Continuous Process Synthesis And Optimization, Emre Gencer Aug 2016

Enabling A Sustainable Economy Through Energy Systems Modeling: Solar-Centric, Efficient, Integrated And Continuous Process Synthesis And Optimization, Emre Gencer

Open Access Dissertations

The expected increase in food, energy and water demand due to increase in population and change in consumption habits in conjunction with diminishing fossil fuel reserves and increasing greenhouse gas emissions urge the development and implementation of alternative energy conversion techniques using renewable energy for a sustainable economy. Among renewable energy sources, solar energy is prominent due to its abundance. A sustainable economy can be created by producing building blocks foundational to meeting all basic human needs of daily existence. However, intermittencies and limitations on land area dedicated to harness solar energy are the major obstacles on widespread implementation of ...


Supporting Space Systems Design Via Systems Dependency Analysis Methodology, Cesare Guariniello Aug 2016

Supporting Space Systems Design Via Systems Dependency Analysis Methodology, Cesare Guariniello

Open Access Dissertations

The increasing size and complexity of space systems and space missions pose severe challenges to space systems engineers. When complex systems and Systems-of-Systems are involved, the behavior of the whole entity is not only due to that of the individual systems involved but also to the interactions and dependencies between the systems. Dependencies can be varied and complex, and designers usually do not perform analysis of the impact of dependencies at the level of complex systems, or this analysis involves excessive computational cost, or occurs at a later stage of the design process, after designers have already set detailed requirements ...


Improving The Laboratory Design Of Asphalt Mixtures To Enhance Asphalt Pavement Durability, Ali Hekmatfar Aug 2016

Improving The Laboratory Design Of Asphalt Mixtures To Enhance Asphalt Pavement Durability, Ali Hekmatfar

Open Access Dissertations

Most departments of transportation, including Indiana’s, currently use the Superpave mixture design method to design asphalt mixtures. This method specifies that the optimum asphalt content for a given gradation be selected at 4 percent air voids. During construction, these mixtures are typically compacted to 7-8 percent air voids. If mixtures were designed to be more compactable in the field they could be compacted to the same density as the laboratory mixture design, which would increase pavement durability by decreasing the in-place air voids. The objective of this research was to enhance the asphalt mixture design method in order to ...


Enhancing Silymarin Fractionation Via Molecular Modeling Using The Conductor-Like Screening Model For Real Solvents, Emma C. Brace Aug 2016

Enhancing Silymarin Fractionation Via Molecular Modeling Using The Conductor-Like Screening Model For Real Solvents, Emma C. Brace

Open Access Theses

The market for bio-based products from plant sources is on the rise. There is a global challenge to implement environmentally clean practices for the production of fuels and pharmaceuticals from sustainable resources. A significant hurdle for discovery of comparable plant-derived products is the extensive volume of trial-and-error experimentation required. To alleviate the experimental burden, a quantum mechanics based molecular modeling approach known as the COnductor-like Screening Model for Real Solvents (COSMO-RS) was used to predict the best biphasic solvent system to purify silymarins from an aqueous mixture. Silymarins are a class of flavonolignans present in milk thistle ( Silybum marianum L ...


Modeling Economic Impacts Of The Inland Waterway Transportation System, Furkan Oztanriseven Aug 2016

Modeling Economic Impacts Of The Inland Waterway Transportation System, Furkan Oztanriseven

Theses and Dissertations

The inland waterway transportation system of the United States (U.S.) handles 11.7 billion tons of freight annually and connects the heartland of the U.S. with the rest of the world by providing a fuel-efficient and environmentally friendly mode of transportation. This dissertation aims to create decision support tools for maritime stakeholders to measure the economic impacts of the inland waterway transportation systems under real world scenarios including disruptions, demand changes, port expansion decisions, and channel deepening investments. Monte Carlo simulation, system dynamics, discrete-event simulation, agent-based modeling, and multiregional input-output modeling techniques are utilized to analyze the complex ...


A Cross-Sectional And Mixed-Method Assessment Of Safety Culture And Safety Climate At A Regional Airline, Micah S. Walala May 2016

A Cross-Sectional And Mixed-Method Assessment Of Safety Culture And Safety Climate At A Regional Airline, Micah S. Walala

Open Access Dissertations

The researcher applied a mixed methods approach to conduct a cross-sectional assessment of the safety culture, safety climate, and SMS at a regional airline in the United States. Data collection techniques were comprised of interview, on-line-survey, and a focus group activity. Participants in the current study were maintenance technicians, flight attendants, dispatchers, pilots, and managers. Results indicated significant differences of perception of safety climate, safety culture, and Safety Management System between the maintenance technicians and flight attendants. The length of time a participant had worked at the subject airline and age of the participant appeared to be significant factors of ...


Asphalt Pavement Preservation Using Rejuvenating Fog Seals, Ammanuiel A. Kebede Apr 2016

Asphalt Pavement Preservation Using Rejuvenating Fog Seals, Ammanuiel A. Kebede

Open Access Theses

Fog seal is a type of treatment that uses a diluted asphalt emulsion to seal and protect an existing asphalt surface from a variety of distresses. Fog seal is sprayed on top of an asphalt pavement surface to improve and protect it from further cracking and raveling. Rejuvenator is also a type of treatment that penetrates into the asphalt pavement and restores its original viscoelastic properties. Similarly, like fog seal, rejuvenators can be sprayed on top of an asphalt pavement surface. The use of rejuvenators has grown rapidly in the past decade. However, little is known about the actual effectiveness ...


Optimal Monitoring And Mitigation Of Systemic Risk In Lending Networks, Zhang Li Apr 2016

Optimal Monitoring And Mitigation Of Systemic Risk In Lending Networks, Zhang Li

Open Access Dissertations

This thesis proposes optimal policies to manage systemic risk in financial networks. Given a one-period borrower-lender network in which all debts are due at the same time and have the same seniority, we address the problem of allocating a fixed amount of cash among the nodes to minimize the weighted sum of unpaid liabilities. Assuming all the loan amounts and cash flows are fixed and that there are no bankruptcy costs, we show that this problem is equivalent to a linear program. We develop a duality-based distributed algorithm to solve it which is useful for applications where it is desirable ...


Dynamic Green Split Optimization In Intersection Signal Design For Urban Street Network, Peng Jiao Apr 2016

Dynamic Green Split Optimization In Intersection Signal Design For Urban Street Network, Peng Jiao

Open Access Theses

In the past few decades, auto travel demand in the United States has significantly increased, but roadway capacity unfortunately has not expanded as quickly, which has led to severe levels of highway traffic congestion in many areas. In theory, the problem of congestion addressed through demand management and roadway expansion. However, system expansion in urban areas is difficult due to the extremely high cost of land; therefore, maximizing the existing capacity therefore often is considered the most realistic option. In urban areas, most of the traffic congestion and delays typically occur at signalized intersections. This thesis aims to prove the ...


Investigating U.S. Resident Perceptions Of Corporate Social Responsibility In Food And Agriculture, Carissa Jae Morgan Apr 2016

Investigating U.S. Resident Perceptions Of Corporate Social Responsibility In Food And Agriculture, Carissa Jae Morgan

Open Access Theses

Corporations are prioritizing corporate social responsibility (CSR) activities by investing in and actively promoting their social practices. In the U.S. of the modern food supply chain creates a unique challenge for corporations to address concerns about social issues of consumers and non-consumers alike. This study is motivated by the need to better understand individuals’ perceptions of CSR as it pertains to the food supply chain. In April 2015 an online survey collected information from 1,201 U.S. residents with the objective of investigating individuals’ perceptions of relative importance of eight prominent CSR areas relevant to food and agriculture ...


A Framework For Organizational Performance Assessment In The Construction Industry, Zenith Rathore Apr 2016

A Framework For Organizational Performance Assessment In The Construction Industry, Zenith Rathore

Open Access Theses

Organizations have been trying to increase their efficiency and improve their performance in order to achieve their goals. Organizational success is determined by various factors that impact organizational performance. Construction industry is a project based industry which is extremely dynamic in nature. The need to identify the weak points and search solutions to improve performance of construction organization is extremely crucial. Previous research works have primarily focused on the measurement of financial or tangible assets. Industry has always focused on measure of project success. However, previous studies lack the understanding of qualitative factors and their combine effect on organizational performance ...


A Methodology For Cooperation Between Electric Utilities And Consumers For Microgrid Utilization Based On A Systems Engineering Approach, Franklin E. Pacheco Chiguano Apr 2016

A Methodology For Cooperation Between Electric Utilities And Consumers For Microgrid Utilization Based On A Systems Engineering Approach, Franklin E. Pacheco Chiguano

Open Access Theses

In recent years, the energy market has experienced important challenges in its structure and requirements of its actors, such as the necessity for more reliable electric service, energy efficiency, environmental care practices, and the incorporation of decentralized power generation based on distributed energy resources (DER). Given this context, microgrids offer several advantages to the grid and its actors. However, few microgrid projects have been implemented, and the participation of electric utilities is lower than the expected. Hence, this research explores how electric utility - customer interactions can accommodate mutual benefits for both parties through the proposal of a Microgrid Reference Methodology ...


Evaluation Of Poisson’S Ratio Of Asphalt Concrete, Elvis Alexander Castillo Camarena Jan 2016

Evaluation Of Poisson’S Ratio Of Asphalt Concrete, Elvis Alexander Castillo Camarena

Theses and Dissertations

Poisson´s ratio can be defined as the negative ratio of strains perpendicular to the load direction to the strains parallel to the loading direction. If elastic or viscoelastic models are used, Poisson´s ratio, together with elastic modulus, is a main input used to predict distresses in flexible pavement structures such as rutting and cracking. In asphalt concrete, Poisson’s ratio is commonly measured using two different testing configurations: indirect tension (IDT) and uniaxial. However, results from these two testing configuration can potentially have differences. Design methodologies such as the Mechanistic Empirical Design Guide (MEPDG, now PavementME) have been ...


A Cradle To Farm Gate Life Cycle Analysis Of Land Use In U.S. Pork Production, William Benjamin Putman Jul 2015

A Cradle To Farm Gate Life Cycle Analysis Of Land Use In U.S. Pork Production, William Benjamin Putman

Theses and Dissertations

The goal of this study was to conduct a detailed Life Cycle Assessment (LCA) of the U.S. live swine production supply chain to quantify land use requirements and to assess the impact associated with various ration compositions. The functional unit was defined as one kilogram (2.2 pounds) of live swine at the farm gate, ready for transport to the abattoir. This assessment focused on the three highest producing USDA regions, which encompassed the Midwest (Regions 5 and 7) and the Southeast (Region 4), representing 86% of U.S. market hog production.

First, a literature review was conducted to ...


Incorporating Environmental And Social Factors Into Decision-Making Of An Oil And Gas Industry To Improve Sustainability, Gaurav Dabhadkar May 2015

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

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 ...


Using The Triple Bottom Line To Select Sustainable Suppliers For A Major Oil And Gas Company, Pandarinath Adarsh Sunkari May 2015

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

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 ...


Evaluation Of Lane Use Management Strategies, Chaitanya Paleti Siva Sai Krishna Oct 2014

Evaluation Of Lane Use Management Strategies, Chaitanya Paleti Siva Sai Krishna

Open Access Theses

The limited funding available for roadway capacity expansion and the growing funding gap, in conjunction with the increasing congestion, creates a critical need for innovative lane use management options. Various cost-effective lane use management strategies have been implemented in the United States and worldwide to address these challenges. However, these strategies have their own costs, operational characteristics, and additional requirements for field deployment. Hence, there is a need for systematic methodologies to evaluate lane use management strategies.

In this thesis, a systematic simulation-based methodology is proposed to evaluate lane use management strategies. It involves identifying traffic corridors that are suitable ...


Heavy Vehicle Rollover Propensity At Roundabouts On Highspeed Roads, Thomas M. Hall Oct 2014

Heavy Vehicle Rollover Propensity At Roundabouts On Highspeed Roads, Thomas M. Hall

Open Access Theses

There is a recent trend of building roundabouts on high-speed roads, often with significant heavy vehicle traffic. With the increased presence of trucks on roundabouts, the issue of rollover has become a concern. Geometric features that allow excessive speed on the approach and entry have been connected to rollover, as well as sudden changes in crossfall and radius. However, the effect on the rollover threshold of changing the roundabout's circulatory superelevation is not fully understood. The impact of aggressive driving behaviors, as displayed by high driver speed far from the roundabout, as well as errors that are manifested by ...


Application Of Bayesian Networks In Consumer Service Industry, Yuan Gao Oct 2014

Application Of Bayesian Networks In Consumer Service Industry, Yuan Gao

Open Access Theses

Gao, Yuan. M.S.I.E., Purdue University. December 2014. Application of Bayesian Networks in Consumer Service Industry. Major professor: Vincent G. Duffy The purpose of the present study is to explore the application of Bayesian networks in the consumer service industry to model causal relationships within complex risk factor structures using aggregate data. An analysis of the Hawaii tourism market was conducted to find out how visitor characteristics affect their behavior and experience as consumers during the trips, and influence the tourism market outcomes represented by measurable factors. Two hypotheses were proposed regarding the use of aggregate data and ...


Designing Sustainable Mentoring Programs: Examining The Role Of Social Community In The Stem College Student Experience, Joi-Lynn Mondisa Oct 2014

Designing Sustainable Mentoring Programs: Examining The Role Of Social Community In The Stem College Student Experience, Joi-Lynn Mondisa

Open Access Theses

In order to begin to understand how to design programs that promote community development and produce beneficial outcomes for community members, we must first define the elements and functions of such a community. In this thesis, I define social community as an environment where like-minded individuals engage indynamic, multidirectional interactions that facilitate social support . Using a human-integrated systems approach, I propose a social community model for STEM minority mentoring programs to understand how a community's design plays a role in the learning and enrichment of its members. The social community model is comprised of three main components: program ...


Capacity-Related Driver Behavior On Modern Roundabouts Built On High-Speed Roads, Shaikh Ahmad Oct 2014

Capacity-Related Driver Behavior On Modern Roundabouts Built On High-Speed Roads, Shaikh Ahmad

Open Access Theses

The objective of this thesis was to investigate the factors that affect capacity-related driver behavior on modern roundabouts built on high-speed roads. The capacity of roundabouts is strongly affected by the behavior of drivers as represented by critical headway (critical gap) and follow-up headway (follow-up time). The effects of heavy vehicles (single-unit truck, bus, and semi-trailer) and area type (rural or urban) on roundabout capacity were investigated by comparing the critical headways for roundabouts located on high-speed and low-speed roads. The effects of nighttime conditions (in the presence of street lighting) were also considered. Data were collected using the Purdue ...


A Dynamic Stochastic Model For Converging Inbound Air Traffic, Jun Chen Oct 2014

A Dynamic Stochastic Model For Converging Inbound Air Traffic, Jun Chen

Open Access Theses

Weather accounts for the majority of congestion in the National Airspace System which highlights the importance of addressing weather uncertainty to mitigate delays, and this paper presents an effort in this direction. Firstly, a new dynamic stochastic 0-1 Integer Programming (IP) model is proposed, which models the Single Airport Ground Holding Problem (SAGHP) with respect to uncertainty in the separation between flights instead of Airport Acceptance Rate (AAR) or landing capacity. Uncertainty in separation according to different weather conditions is represented through the scenario tree by using stochastic linear programming. Considering time separation constraints instead of AAR constraints, our model ...