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Automated Segmentation, Detection And Fitting Of Piping Elements From Terrestrial Lidar Data, Yun-Ting Su
Automated Segmentation, Detection And Fitting Of Piping Elements From Terrestrial Lidar Data, Yun-Ting Su
Open Access Dissertations
Since the invention of light detection and ranging (LIDAR) in the early 1960s, it has been adopted for use in numerous applications, from topographical mapping with airborne LIDAR platforms to surveying of urban sites with terrestrial LIDAR systems. Static terrestrial LIDAR has become an especially effective tool for surveying, in some cases replacing traditional techniques such as electronic total stations and GPS methods. Current state-of-the-art LIDAR scanners have very fine spatial resolution, generating precise 3D point cloud data with millimeter accuracy. Therefore, LIDAR data can provide 3D details of a scene with an unprecedented level of details. However, automated exploitation …
Behavior And Design Of Steel-Plate Composite (Sc) Walls For Blast Loads, Jakob C Bruhl
Behavior And Design Of Steel-Plate Composite (Sc) Walls For Blast Loads, Jakob C Bruhl
Open Access Dissertations
Reinforced concrete (RC) structures have historically been the preferred choice for blast resistant structures because of their mass and the ductility provided by steel reinforcement. Steel-plate composite (SC) walls are a viable alternative to RC for protecting the infrastructure against explosive threats. SC structures consist of two steel faceplates with plain concrete core between them. The steel faceplates are anchored to the concrete using stud anchors and connected to each other using tie bars. SC structures provide mass from the concrete infill and ductility from the continuous external steel faceplates. This dissertation presents findings and recommendations from experimental and analytical …
Near-Inertial Internal Poincare Waves In Lake Michigan: Seasonal Variability And Effects On Lateral Dispersion And Turbulent Mixing, Jun M Choi
Open Access Dissertations
A dominant physical process in stratified Lake Michigan is near-inertial internal Poincaré waves. The near-inertial internal Poincaré waves is described as locally quasi-uniform currents in the lateral direction, with vertically-sheared structures rotating clockwise at a near-inertial period. The goal of this dissertation is to investigate their seasonal variation and the potential roles on lateral dispersion and vertical mixing. ^ At this mid-lake location, the Poincaré wave is seen to describe more than 80% of the observed surface current variability for much of the year, with characteristic near-inertial frequency and clockwise-rotating velocities. The wave persists during the stratified period, and is …
Modeling Person-To-Person Contaminant Transport In Enclosed Environments, Chun Chen
Modeling Person-To-Person Contaminant Transport In Enclosed Environments, Chun Chen
Open Access Dissertations
It is essential to predict person-to-person contaminant transport in enclosed environments to improve air distribution design and reduce the infection risk from airborne infectious diseases. This study aims to improve and accelerate the simulation of person-to-person contaminant transport in enclosed environments. ^ This investigation first conducted experimental measurements of person-to-person contaminant transport in an office mockup and the first-class cabin of a functional MD-82 aircraft. The experimental data of steady-state airflow, temperature, and gas contaminant concentration fields obtained in the office were used to validate the steady-state computational fluid dynamics (CFD) models. In the aircraft cabin, the transient particle concentrations …
An Integrated System Of Vapor-Compression Chiller And Absorption Heat Pump: Experiment, Modeling, And Energy And Economic Evaluation, Yi-Shu Kung
Open Access Dissertations
Buildings currently consume 41% of the primary energy in the United States. Among the 41% primary energy, approximate 50% are used for building heating, cooling, and water heating. Improving the efficiencies of the devices for building heating and cooling has potentials to reducing the energy consumptions. This research aims to find one solution for building energy efficiency through investigating an Integrated System of an Integrated Compression-Absorption Subcooling System (ICASS) Based upon the principle of subcooling effect, the ICASS can improve the efficiency of the cooling device but also achieve additional useful heating sources potentially used for space heating and domestic …
Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon
Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon
Open Access Dissertations
Ecosystem services are benefits that people receive from the environment. Despite recent exponential increases in ecosystem service research, the ecosystem service framework has made little impact on policy and land management decisions, especially in the United States. Two of the main limitations for a lack of ecosystem service considerations in both policy and land management decisions are a need for more advanced quantification methods and the lack of engagement of key stakeholders who are responsible for making land management decisions. This research seeks to address these two limitations by testing and improving quantification methods of ecosystem services and by evaluating …
Algorithms For Bundling And Pricing Trucking Services: Deterministic And Stochastic Approaches, Rodrigo Mesa-Arango
Algorithms For Bundling And Pricing Trucking Services: Deterministic And Stochastic Approaches, Rodrigo Mesa-Arango
Open Access Dissertations
Bundling and pricing trucking services is an important strategic decision for carriers. This is helpful when they consider the incorporation of new businesses to their networks, look for economic and optimal operations, and develop revenue management strategies. Reverse combinatorial auctions for trucking services are real-world examples that illustrate the necessity of such strategies. In these auctions, a shipper asks carriers for quotes to serve combinations of lanes and the carriers have to bundle demand and price it properly. This dissertation explores several dimensions of the problem employing state-of-the-art analytical tools. These dimensions include: Truckload (TL) and less-than-truckload (LTL) operations, behavioral …
Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy
Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy
Open Access Theses
Aside from a safe flight, airline passengers expect to arrive to their destination on time. With an abundance of flights in the United States arriving late each day, it has yet to be determined if the airport's layout plays a role. This research looks at four common runway configuration types at hub and non-hub airports to determine if runway configurations affect arrival delays. A two-way ANOVA is conducted comparing the means of the on-time arrival percentage between airports exhibiting each of the four runway configurations as well as hub and non-hub airport status. The results determine if any or none …
Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg
Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg
Open Access Theses
Despite the fact that the soil profile is known to impact streamflow, most Curve Number (CN)-based models ignore subsurface processes. This study explores the influence of soil storage on peak flows. Two watersheds in flat, humid west-central Indiana were modeled using both the Natural Resources Conservation Service (NRCS) Curve Number and four versions of the Soil Moisture Accounting (SMA) loss methods in the United States Army Core of Engineers-developed (USACE) Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS). One watershed encompasses the Wabash and Tippecanoe Rivers' confluence; the other contains an ephemeral stream, Plum Creek. The CN-based model was developed using …
Numerical Characterization Of Convective Heat Transfer Of Low-Rise Buildings, Ranchi Chen
Numerical Characterization Of Convective Heat Transfer Of Low-Rise Buildings, Ranchi Chen
Open Access Theses
The convective heat transfer coefficient (CHTC) is an important parameter to evaluate the efficiency of building-integrated photovoltaic/Thermal (PV/T) system and the energy exchange within the turbulent atmospheric boundary layer. Reynolds-average Navier-Stokes approach has been frequently used to predict the CHTC at the surface of low rise roof but incapable of predicting transient behavior of separation, reattachment and recirculation both on the windward and leeward surface. However, Large Eddy Simulation approach (LES) could provide accurate flow field and temperature field around the low rise building. ^ The current study uses Large Eddy Simulation with Smagorinsky-Lily model and the Shear Stress Transport …
Quantifying Moisture Transport In Cementitious Materials Using Neutron Radiography, Catherine L. Lucero
Quantifying Moisture Transport In Cementitious Materials Using Neutron Radiography, Catherine L. Lucero
Open Access Theses
A portion of the concrete pavements in the US have recently been observed to have premature joint deterioration. This damage is caused in part by the ingress of fluids, like water, salt water, or deicing salts. The ingress of these fluids can damage concrete when they freeze and expand or can react with the cementitious matrix causing damage. To determine the quality of concrete for assessing potential service life it is often necessary to measure the rate of fluid ingress, or sorptivity. Neutron imaging is a powerful method for quantifying fluid penetration since it can describe where water has penetrated, …
Examining Unawareness Of Construction Law Principles From A Small Contractor's Perspective, Ketaki Shiralkar
Examining Unawareness Of Construction Law Principles From A Small Contractor's Perspective, Ketaki Shiralkar
Open Access Theses
Construction industry encompasses myriads of small trades within itself. If we take a microscope and observe, what looks from outside as one big single unit, is in fact made up of many small cogs of a wheel, important ones though, as without them, the functionality of the industry wouldn't be proper. As much as the existence of these small scale contractor's companies is important, so is their survival. There have been many reasons as to why contractors fail, but this study is limited to focus on one of them, which is, the absence of legal knowledge among employees of a …
Investigation Of Industry Perceptions Of Building Information Modeling (Bim)-Based Estimating Practices In The U.S. And China, Zhihang Yi
Open Access Theses
While the Building Information Modeling (BIM) technology has been seen as next revolutionary technology for the Architectural, Engineering, Construction and Facility Management (AEC/FM) fields, the AEC/FM industry does not implement BIM technology on the cost estimating practices as widely as expected. The efficiency improvement on cost estimating with BIM could be accomplished through automating quantity take-offs, closely collaborating design with the estimating professionals and so on. This research explores the advantages and barriers of imbedding BIM technology into the estimating practices which enables the industry deepen their understandings on BIM-based cost estimation method. This study also compares the industry perceptions …
Seismic In-Plane Response Of Reinforced Concrete Frames With Masonry Infill Walls, Rabab Abdel Karim Al Louzi
Seismic In-Plane Response Of Reinforced Concrete Frames With Masonry Infill Walls, Rabab Abdel Karim Al Louzi
Open Access Dissertations
Field data gathered after destructive earthquakes indicate that infill walls interact with reinforced concrete (RC) frames in buildings during an earthquake and could cause failure mechanism different than what the frames are originally designed for. A new method to identify the failure modes of RC frames with infill walls is developed. The method requires only the simple geometric and material properties of the elements involved in the frame- wall assembly. The approach checks various possible failure mechanisms, including those that may evolve depending on how the infill wall may fail during strong shaking, for example, the dynamically evolved captive column …
Photochemistry Of Single-Walled Carbon Nanotubes In The Aquatic Environment, And Their Extraction From Soils, Somayeh Beigzadehmilani
Photochemistry Of Single-Walled Carbon Nanotubes In The Aquatic Environment, And Their Extraction From Soils, Somayeh Beigzadehmilani
Open Access Dissertations
Carbon nanotubes (CNTs) are a class of engineered nanoparticles, composed of an array of sp2 carbon atoms arranged as fused benzene rings. Due to their exceptional electrical, mechanical, and physical properties, CNTs find applications in construction, aerospace, and medical industries. In the United States, CNTs already had an annual production of 2,000 tons in 2011. This rate of annual production indicates that CNTs will find their way into the environment, which will result in certain environmental exposure. Yet, there have not been sufficient and definitive studies on the health and environment effects of CNTs. For example, additional information regarding environmental …
International Water And Food Security Development: Performance Evaluation And Assessment Of Research Needs At Multiple Scales, Caitlin Anne Grady
International Water And Food Security Development: Performance Evaluation And Assessment Of Research Needs At Multiple Scales, Caitlin Anne Grady
Open Access Dissertations
Water and food security remain the top development challenges of the decade, and perhaps the century. Since the Millennium Development Goals were established in 2000, billions of people have obtained access to more food, better nutrition, improved water, and basic sanitation facilities worldwide. This progress has been accomplished through the dedication of international organizations, non-governmental organizations, country-level governments, private corporations, and individuals at international, regional, and local scales. Truly tremendous strides have been made in water and food provisioning for humans worldwide. These past two decades have also seen the largest population growth on record, the highest rates of childhood …
Improvement Of Simulating Bmps And Lid Practices In L-Thia-Lid Model, Yaoze Liu
Improvement Of Simulating Bmps And Lid Practices In L-Thia-Lid Model, Yaoze Liu
Open Access Dissertations
Best management practices (BMPs) and low impact development (LID) practices are popular approaches used to reduce the negative impacts of urbanization on hydrology and water quality. To assist planners and decision-makers in urban development projects, user-friendly tools are needed to assess the effectiveness of BMPs and LID practices on water quantity and quality. To address this need, the Long-Term Hydrologic Impact Assessment-LID (L-THIA-LID) model was enhanced with additional commonly used BMPs and LID practices represented in the model, improved approaches to estimate hydrology and water quality, and representation of practices in series. The tool was used to evaluate the performance …
Distributed Real-Time Hybrid Simulation: Modeling, Development And Experimental Validation, Ali Irmak Ozdagli
Distributed Real-Time Hybrid Simulation: Modeling, Development And Experimental Validation, Ali Irmak Ozdagli
Open Access Dissertations
Real-time hybrid simulation (RTHS) has become a recognized methodology for isolating and evaluating performance of critical structural components under potentially catastrophic events such as earthquakes. Although RTHS is efficient in its utilization of equipment and space compared to traditional testing methods such as shake table testing, laboratory resources may not always be available in one location to conduct appropriate large-scale experiments. Consequently, distributed systems, capable of connecting multiple RTHS setups located at numerous geographically distributed facilities through information exchange, become essential. This dissertation focuses on the development, evaluation and validation of a new distributed RTHS (dRTHS) platform enabling integration of …
Spatial Analysis Of Passenger Vehicle Use And Ownership And Its Impact On The Sustainability Of Highway Infrastructure Funding, Matthew Volovski
Spatial Analysis Of Passenger Vehicle Use And Ownership And Its Impact On The Sustainability Of Highway Infrastructure Funding, Matthew Volovski
Open Access Dissertations
Across the United States, the sustainability of highway funding is at risk due to increasing need and uncertainty in the factors that drive revenue. Past studies on highway funding sustainability have identified that the root cause of changing highway revenue are the shifts in social demographics and economic characteristics. Unfortunately, from the revenue perspective (the focus of this dissertation), the ability of previous research to account for these factors has been rather limited in two ways; first, the inability to accurately assess current regional vehicle use (a typical prerequisite for statistical modeling of highway revenues) due to difficulties associated with …
A Probabilistic Model Of Benefit-Cost Analysis For Highway Construction Projects, Yue He
A Probabilistic Model Of Benefit-Cost Analysis For Highway Construction Projects, Yue He
Open Access Theses
Deterministic method occupies the predominant position in economic analysis. However, by using a single value to estimate the project value, deterministic method would hide the risk under it. Analysts may make incorrect judgments by looking at a value without knowing the likelihood of its occurrence and the consequences of its occurrence. A probabilistic model was developed in this study to address this problem. It was found in this study that the traffic flows on Indiana highways follow logistic distributions rather than normal distributions as generally believed. The application of the probabilistic model was illustrated through a case study. The results …
The Effect Of Maximum Aggregate Size On The Shear Strength Of Geometrically Scaled Reinforced Concrete Beams, Derek Robert Daluga
The Effect Of Maximum Aggregate Size On The Shear Strength Of Geometrically Scaled Reinforced Concrete Beams, Derek Robert Daluga
Open Access Theses
Shear strength of reinforced concrete beams without web reinforcement has been reported to decrease with increases in depth. This is often referred to as a size effect. This reduction in shear strength has been reported to decrease with the use of web reinforcement and increases in maximum aggregate size. ^ The purpose of this study was to test two hypotheses 1) shear strength increases with increases in maximum aggregate size and 2) aggregate gradation affects this increase in shear strength. Maximum aggregate size is defined here as the size of the smallest sieve opening through which all aggregate particles pass. …
Low Income, Supermarket Accessibility, And The Transportation Network: A Multimodal Analysis Identifying Areas Of Poor Accessibility And Intervention Strategies In Indianapolis, Indiana, Andrea Leigh Bailey
Low Income, Supermarket Accessibility, And The Transportation Network: A Multimodal Analysis Identifying Areas Of Poor Accessibility And Intervention Strategies In Indianapolis, Indiana, Andrea Leigh Bailey
Open Access Theses
The United States Department of Agriculture (USDA) Economic Research Service estimates that 23.5 million people live in food deserts, over half of which are considered low-income residents. Accurately defining a food desert is crucial as the designated areas can benefit from grant opportunities and funding priority. To qualify as an urban food desert, the USDA requires that at least 500 residents or one-third of the population live outside a one-mile buffer from a supermarket as well as have a median income of less than 80% of the area average or a poverty rate of greater than 20%. Approaches in the …
Behavior Of Reinforced Concrete Panels Subject To Impact By Non-Deformable Projectiles, Amer Abdel Karim Alkloub
Behavior Of Reinforced Concrete Panels Subject To Impact By Non-Deformable Projectiles, Amer Abdel Karim Alkloub
Open Access Dissertations
In impact resistance of reinforced concrete (RC) panels against projectiles the contribution of the orthogonal mesh reinforcement has been ignored. In this study the contribution of mesh reinforcement to impact resistance and itseffect on the nature of local damage caused by impact of non-deformable projectiles are investigated. The investigation included a combination of 53 experiments and series of finite-element based numerical simulations. Three levels of local damage modes were investegated based on the severity of the degree of damage in the impacted panels. Mesh reinforcement ratio within the range of reinforcement ratio considered, namely 0.19% to 0.48%, was irrelevant to …
Overweight Vehicle Permitting Alternatives, Stephanie R Everett
Overweight Vehicle Permitting Alternatives, Stephanie R Everett
Open Access Dissertations
Overweight vehicles exceed the federal and/or state statutory limits for either the gross vehicle weight (GVW) or the weight of individual axles or axle groups. National and state limits on vehicle weights were established to preserve the highway infrastructure. Past research has shown that overweight operations, while causing significant damage to roads and bridges, can enhance the trucking industry productivity, and thus yield economic benefits both regionally and nationally. In the United States, individual states administer oversize and overweight vehicle permit programs to regulate and collect revenues from overweight operations. Differences in the truck size and weight limits and overweight …