Digital Commons Network^™

State Of The Art In Composition, Fabrication, Characterization, And Modeling Methods Of Cement-Based Thermoelectric Materials For Low-Temperature Applications, Xiaoli Liu, Ruchita Jani, Esther Orisakwee, Conrad Johnston, Piotr Chudzinski, Ming Qu, Brian Norton, Niall Holmes Dr., Jorge Kohanoff, Lorenzo Stella, Hongxi Yin, Kazuaki Yazawa

Articles

The worldwide energy crisis and environmental deterioration are probably humanity’s greatest challenges. Thermoelectricity, which allows for the mutual conversion between thermal and electrical energy, has become a promising technology to alleviate this challenge. Increasingly more research focuses on how to fabricate and apply thermoelectric materials for harvesting energy and regulating the indoor thermal environment. However, only a few studies have focused on cementitious materials with thermoelectric potential. Thermoelectric cement is a composite material in which particular additives can enhance the thermoelectric performance of ordinary cement. By potentially replacing traditional construction materials with thermoelectric cement in building applications, electricity could be …

A Density Functional Theory Study On Using Montmorillonite To Reduce Air Pollution, Triati Dewi Kencana Wungu, Meqorry Yusfi, Suprijadi Suprijadi

Makara Journal of Technology

In this study, density functional theory (DFT) method is used to investigate the possibility of using a smectite clay mineral called montmorillonite (MMT) in reducing heavy metals, such as Cd, through Cd adsorption. The mechanism of Cd adsorption in MMT is observed theoretically, and the tetrahedrally isomorphic substitution on the upper layer of MMT is considered to observe the role of Al and Fe in strengthening Cd adsorption. Two types of MMT are modeled in this study: Al-MMT and Fe-MMT. The Al-MMT means that Al substitutes one atom in the upper tetrahedral layer of MMT, while Fe-MMT means that Fe …

Use Of Viscoplastic Damper For Improving The Resistance Of Steel Frames To Blast Loading, Gholamreza Abdollahzadeh, Hadi Faghihmaleki, Hamed Hamidi Jamnani, Atefeh Ebrahimi Bardar

Makara Journal of Technology

In this paper, we evaluated the effect of viscoplastic dampers on the response of steel frames under blast loading. We used SAP2000 software and link elements to investigate the responses of nine-story steel frames with and without dampers. The proposed viscoplastic damper is a new type of viscous damper. The application of this damper is based on the availability of its constituent materials. The damper acts as a viscoelastic damper at low levels of vibration, but it acts as a combination of viscoelastic operator and metal-yielding device at extreme levels of vibration. With respect to the height of the structure, …

A One‐Dimensional Model For Turbulent Mixing In The Benthic Biolayer Of Stream And Coastal Sediments, Stanley B. Grant, Jesus D. Gomez‐Velez, Marco Ghisalberti, Ian Guymer, Fulvio Boano, Kevin Roche, Judson Harvey

Civil Engineering Faculty Publications and Presentations

In this paper, we develop and validate a rigorous modeling framework, based on Duhamel's Theorem, for the unsteady one‐dimensional vertical transport of a solute across a flat sediment‐water interface (SWI) and through the benthic biolayer of a turbulent stream. The modeling framework is novel in capturing the two‐way coupling between evolving solute concentrations above and below the SWI and in allowing for a depth‐varying diffusivity. Three diffusivity profiles within the sediment (constant, exponentially decaying, and a hybrid model) are evaluated against an extensive set of previously published laboratory measurements of turbulent mass transfer across the SWI. The exponential diffusivity profile …

Effect Of Citric Acid On Slump, Compressive Strength, And Setting Time Of Belitic Calcium Sulfoaluminate Concrete, Israel Aguilar Rosero

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate (BCSA) cement has well established advantages related to fast setting time, fast strength gain, long-term strengths, shrinkage, and sustainability. Due to its fast setting and hardening, this type of cement has historically been used to repair concrete structures, highways, and runways. This work provides much needed guidance on establishing mix design criteria for BCSA cement. Guidance is also given on the effects of set retarders on strength, slump, and setting times. Citric acid and a phosphonic acid-based admixture were tested as retarders for different concrete mixtures. Three studies were performed. In the slump study five different water …

Seismic Loading Effects Within Orthogonally Connected Steel Lateral Force Resisting Systems, Alhussin Faraj Aliwan

Graduate Theses and Dissertations

Steel buildings located within seismically active regions require special design considerations to ensure public safety and prevent collapse during an extreme seismic event. Two commonly used steel systems are special moment frames (SMFs) and buckling-restrained braced frames (BRBFs). When two seismic systems share a common column in an orthogonal configuration (such as at a building corner), design specifications currently consider a 100+30 rule wherein the shared column is designed for 100% fuse demand in one direction, plus 30% fuse demand from the other direction. While this rule has been shown to be reasonable for elastic building response, a few studies …

Development Of Deterioration Models For Street Pavement In Dallas-Fort Worth Metroplex, Mladjan John Grujicic

Civil Engineering Dissertations - Archive

Accurate prediction of pavement deterioration is vital for an efficient and cost-effective allocation of available budgets for keeping an agency’s road networks operating at a desirable level. Currently, most cities in the Dallas-Fort Worth Metroplex area are using the software PAVERTM and the associated performance models to predict future conditions as they do not have available reliable prediction models. However, the problem with this type of modeling is that the models are not calibrated to local conditions. The Pavement Deterioration Prediction models that have been developed in this research will help any pavement management agencies within DFW Metroplex area to …

Use Of Time-Domain Reflectometry To Characterize Thermal And Hydraulic Properties Of Unsaturated Sands, Xuelin Wang

Civil Engineering Dissertations - Archive

Unsaturated soil is an essential consideration for many geotechnical engineering fields, for example, soil bearing capacity, soil lateral earth pressure, slope stability analysis, and seepage-related problems. Thermal-hydro-mechanical (THM) processes govern the behavior of unsaturated soils. Therefore, it is critical to simultaneously measure soil moisture, density, and thermal properties to better study THM processes. A thermo-time-domain reflectometry (thermo-TDR) sensor, a dual-probe for both soil moisture and thermal properties, is improved (based on its previous design) and fully calibrated through various soils at different soil moisture circumstances. Nine different chemical reagents with known dielectric constant were utilized to perform calibration of the …

Carbon Sequestration By Reforesting Legacy Grasslands On Coal Mining Sites, James F. Fox, J. Elliott Campbell, Peter M. Acton

Civil Engineering Faculty Publications

Future carbon management during energy production will rely on carbon capture and sequestration technology and carbon sequestration methods for offsetting non-capturable losses. The present study quantifies carbon sequestration via reforestation using measurements and modeling for recent and legacy surface coal mining grasslands that are re-restored through tree planting. This paper focuses on a case study of legacy coal mining sites in the southern Appalachia the United States. This five million-hectare region has a surface mining footprint of approximately 12% of the land area, and the reclamation method was primarily grassland. The results of the soil carbon sequestration rates for restored …

Impact Of Disadvantaged Business Enterprises Participation And Mobilization Cost On Highway Project Performance, Shristy Maharjan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction practitioners have their goals to complete projects within time without exceeding the allocated budget. However, studies have shown many projects overrun their allocated budget and face delays due to numerous reasons. Some of the main reasons are lack of efficient construction and financial resource management, lack of proper planning, and unavailability of new construction technologies, as well as ineffective supervision and communication, design changes, and unskilled workers. In some studies, mobilization costs, along with the participation of Disadvantaged Business Enterprises (DBEs) in projects were identified as factors affecting the cost and schedule performance of construction projects. However, no statistical …

Understanding Mesoscopic Chemo-Mechanical Distress And Mitigation Mechanisms Of Concrete Subject To Asr, Md Asif Rahman

Boise State University Theses and Dissertations

Alkali-silica reaction (ASR) is one of the common sources of concrete damage worldwide. The surrounding environment, namely, temperature and humidity greatly influence the alkali-silica reaction induced expansion. Global warming (GW) has caused frequent change in the climate and initiated extreme weather events in recent years. These extreme events anticipate random change in temperature and humidity, and convey potential threats to the concrete infrastructure. Moreover, external loading conditions also affect the service life of concrete. Thus, complex mechanisms of ASR under the impact of seasonal change and global warming require a precise quantitative assessment to guide the durable infrastructure materials design …

Traffic Time Headway Prediction And Analysis: A Deep Learning Approach, Saumik Sakib Bin Masud

Theses and Dissertations

In the modern world of Intelligent Transportation System (ITS), time headway is a key traffic flow parameter affecting ITS operations and planning. Defined as “the time difference between any two successive vehicles when they cross a given point”, time headway is used in various traffic and transportation engineering research domains, such as capacity analysis, safety studies, car-following, and lane-changing behavior modeling, and level of service evaluation describing stochastic features of traffic flow. Advanced travel and headway information can also help road users avoid traffic congestion through dynamic route planning, for instance. Hence, it is crucial to accurately model headway distribution …

Enhanced Traffic Incident Analysis With Advanced Machine Learning Algorithms, Zhenyu Wang

Computational Modeling & Simulation Engineering Theses & Dissertations

Traffic incident analysis is a crucial task in traffic management centers (TMCs) that typically manage many highways with limited staff and resources. An effective automatic incident analysis approach that can report abnormal events timely and accurately will benefit TMCs in optimizing the use of limited incident response and management resources. During the past decades, significant efforts have been made by researchers towards the development of data-driven approaches for incident analysis. Nevertheless, many developed approaches have shown limited success in the field. This is largely attributed to the long detection time (i.e., waiting for overwhelmed upstream detection stations; meanwhile, downstream stations …

Robust Maximum Coverage Facility Location Problem With Drones Considering Uncertainties In Battery Availability And Consumption, Darshan Chauhan, Avinash Unnikrishnan, Miguel Figliozzi, Stephen D. Boyles

Civil and Environmental Engineering Faculty Publications and Presentations

Given a set of spatially distributed demand for a specific commodity, potential facility locations, and drones, an agency is tasked with locating a prespecified number of facilities and assigning drones to them to serve the demand while respecting drone range constraints. The agency seeks to maximize the demand served while considering uncertainties in initial battery availability and battery consumption. The facilities have a limited supply of the commodity being distributed and also act as a launching site for drones. Drones undertake one-to-one trips (from located facility to demand location and back) until their available battery energy is exhausted. This paper …

Incorporating Shear Resistance Into Debris Flow Triggering Model Statistics, Noah J. Lyman

Master's Theses

Several regions of the Western United States utilize statistical binary classification models to predict and manage debris flow initiation probability after wildfires. As the occurrence of wildfires and large intensity rainfall events increase, so has the frequency in which development occurs in the steep and mountainous terrain where these events arise. This resulting intersection brings with it an increasing need to derive improved results from existing models, or develop new models, to reduce the economic and human impacts that debris flows may bring. Any development or change to these models could also theoretically increase the ease of collection, processing, and …

Evaluation Of Accumulated Strain From Both Cyclic Triaxial And Static Creep Tests On Unbound Pavement Materials, Amir Mohammad Sajjadi

Theses and Dissertations

In this research, the behavior of Limerock (LR) aggregates blended with different reclaimed asphalt pavement (RAP) materials were investigated as an unbound base layer. Various combinations of LR and RAP, including 100%LR, 25%RAP75%LR, 50%RAP50%LR, and 100%RAP, were evaluated. Three main experiments performed on the samples were: static creep, static triaxial test, and cyclic triaxial test. The cyclic triaxial test was performed to measure the resilient modulus (MR) of materials. The results of the static triaxial test for 100% RAP showed that the deviator stress at failure steadily increased by increasing the confining pressure, while the 100% LR showed a maximum …

Environmental Hygiene For Covid-19: It's All About The Mask, Daniel B. Oerther, Mona Shattell

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Cost-Effective Planning Strategies For Battery Electric Bus Systems, Yi He

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, actions have been taken by countries around the world to create a more sustainable energy future. Electrifying transit buses is considered as a promising option to reduce emissions and increase sustainability of the transportation sector. However, there are still several barriers to the adoption of electric buses (e-buses). The barriers include, but are not limited to, the range limitations of e-buses, high up-front costs of e-buses, large capital expenses for charging infrastructure, and a lack of understanding regarding e-bus operation and management. This dissertation aims to overcome these barriers through the development of cost-effective planning strategies from …

Detailed Modeling Of The Flash Hydrolysis Of Algae For Biofuel-Production In Comsol Multiphysics, Noah Joseph Legrand

Mechanical & Aerospace Engineering Theses & Dissertations

Algae-derived biofuels are being commercialized as an important renewable energy source. Like any new technology, conversion improvements are desired, including reductions in process complexity and better utilization of the entire microalgae feedstock. The Old Dominion Biomass Laboratory has focused on flash hydrolysis for algae biofuel production. That process involves rapidly heating algae and water mixed as a slurry to a subcritical state. Results from small-scale bench tests are promising, but process scale up is a challenge. Currently there exists a pilot laboratory scale system utilizing induction heating in order to reach controlled reaction temperatures with a reaction duration of 10 …

Assessing Grassed Waterway Implementation Using Acpf And Swat Models, Kirsten Schaefer

Graduate Theses/Dissertations

Agriculture is the most significant contributor of nonpoint source pollutants in US waterways, with sediment being the most prevalent cause of impairments. Sediment loss mitigation occurs through Best Management Practices (BMPs), such as grassed waterways. Federal and state agencies incentivize the implementation of BMPs through cost-share programs for farmers. The investment of public funds has increased pressure to demonstrate the effectiveness and value of individual projects, necessitating the development of strategies for prioritizing projects based on the sensitivity of sites to sediment erosion and optimal locations for implementation. This study has three primary objectives: (i) document existing locations of grassed …

Exploring The Feasibility Of Introducing Alternative Fuel Vehicles Into Fleet, Samia Rubaiat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Transportation is one of the most significant contributing sectors to emissions and consequently air pollution in the United States. Many state and private fleet agencies have announced their visions of zero-emission fleet programs. Adopting alternative fuel vehicle (AFV) is a viable option for achieving this objective. AFVs offer lower emissions along with low operating and maintenance costs, and higher fuel economy. The advancement of technologies has provided several AFV options, such as hybrid electric vehicles (HEV), electric vehicles (EV), compressed natural gas vehicles (CNGV), and liquefied petroleum gas vehicles (LPGV). The main challenges in adopting AFVs are the high purchasing …

Designing Next-Generation Transportation Systems With Emerging Vehicle Technologies, Zhiwei Chen

USF Tampa Graduate Theses and Dissertations

Recent advances in computing and artificial intelligence have enabled the development of various emerging vehicle technologies, e.g., autonomous vehicles (AV) and modular autonomous vehicles (MAV). These technologies bring new scientific and engineering problems challenging transportation researchers and practitioners. This dissertation aims to develop a suite of scalable computational and analytical tools for designing and analyzing next-generation transportation systems with the MAV technologies. Also, we intend to empirically study the system impacts in terms of the quality of service, energy implications, and inequality impacts.

For MAV system design, we develop a methodological framework centering at theoretical properties of the optimal system …

Analysis Of Electric Vehicle Charging Behavior Patterns With Function Principal Component Analysis Approach, Chenxi Chen, Yang Song, Xianbiao Hu, Ivan G. Guardiola

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This manuscript focused on analyzing electric vehicles’ (EV) charging behavior patterns with a functional data analysis (FDA) approach, with the goal of providing theoretical support to the EV infrastructure planning and regulation, as well as the power grid load management. 5-year real-world charging log data from a total of 455 charging stations in Kansas City, Missouri, was used. The focuses were placed on analyzing the daily usage occupancy variability, daily energy consumption variability, and station-level usage variability. Compared with the traditional discrete-based analysis models, the proposed FDA modeling approach had unique advantages in preserving the smooth function behavior of the …

A Framework For Assessing The Reliability, Availability, Maintainability, And Safety (Rams) Of Decentralized Sanitation, Adefunké Adeosun

USF Tampa Graduate Theses and Dissertations

In established industry sectors, Reliability, Availability, Maintainability, and Safety (RAMS) risk assessments are normally used to compare the risks associated with different technologies on process units. Sanitation solutions are split into traditional wastewater treatment which is centralized treatment and can be classified as an established industry, and decentralized treatment such as pit latrines and septic tank systems which are on much smaller scales. Also they can be classified as non-conventional methods such as reinvented advanced decentralized non-sewered sanitation solution techniques exist mainly in two forms as “Single-User Reinvented Toilet (SURT)” systems or “Multiple-User Reinvented Toilet (MURT)” systems. Advanced decentralized non-sewered …

Coral Reef Restoration In The Tropical West Atlantic Amid The Covid-19 Pandemic, Linden Cheek

USF Tampa Graduate Theses and Dissertations

Climate change is increasing threats to coasts, both from storm surge and sea level rise. Healthy coral reefs provide reduction in storm surges, wave energy, coastal flooding and everyday erosion, and are found across a variety of spatial scales. Given the state of coral reefs worldwide, active Coral Reef Restoration (CRR) in emerging as a necessary component of coastal protection. CRR can be classified as a nature-based solutions (NbS) for coastal protection that also provides a multitude of ecosystem-based services to both humans and other life. Nearly all literature on coral restoration efforts assume a steady-state of human-ecological interactions, but …

Improvement Of The Effectiveness Of Greywacke Crushing Process By Applying An Impact Crusher In Quarry For The Production Of Railway Ballast, Krzysztof Kurus, Karolina Jąderko-Skubis

Journal of Sustainable Mining

The production of aggregates in rock mining requires an optimal system of crushers, separators and conveyors. Proper machine selection allows to obtain aggregates with appropriate technical parameters and increase the output of required fractions with a given unit cost. The usage of rock raw materials for the production of railway ballast used in the railway track superstructure is connected with the necessity to meet strictly defined quality requirements.

This paper presents an example of the use of an impact crusher in a selected quarry for the purpose of obtaining the correct parameters of railway ballast and a suitable grain curve. …

Atmospheric Measurements With Unmanned Aerial Systems (Uas), Marcelo I. Guzman

Chemistry Faculty Publications

This Special Issue provides the first literature collection focused on the development and implementation of unmanned aircraft systems (UAS) and their integration with sensors for atmospheric measurements on Earth. The research covered in the Special Issue combines chemical, physical, and meteorological measurements performed in field campaigns as well as conceptual and laboratory work. Useful examples for the development of platforms and autonomous systems for environmental studies are provided, which demonstrate how careful the operation of sensors aboard UAS must be to gather information for remote sensing in the atmosphere. The work serves as a key collection of articles to introduce …

A Modelling Study For Smart Pigging Technique For Pipeline Leak Detection, Caitlyn Judith Thiberville

LSU Master's Theses

Although leak incidents continue, a pipeline remains the most reliable mode of transportation within the oil and gas industry. It becomes even more important today because the projection for new pipelines is expected to increase by 1 billion BOE through 2035. In addition, increasing number and length of subsea tiebacks face new challenges in term of data acquisition, monitoring, analysis, and remedial actions. Passive leak-detection methods commonly used in the industry have been successful with some limitations in that they often cannot detect small leaks and seeps. In addition to a thorough review of related topics, this study investigates how …

Real Records Scaling Factors Optimization To Fit The Syrian Design Spectra Using Genetic Algorithm, Seraj Jdyd

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

After selecting real seismic records it is necessary to scale these records to match the intensity of the earthquake expected for the site. Generally, scaling can be made by ground motions uniform scaling in time domain which is simply scaled up or down the ground motions uniformly to best match (in average) the target spectrum within a period range of interest. It’s an engineer’s job to find the best scaling factors to best match the target spectrum, which is a complex task, so we employed the Genetic Algorithm (GA) in finding those scaling factors to achieve the best results.

Genetic …

Laboratory Results And Mathematical Modeling Of Spore Surface Interactions In Stormwater Runoff, Anne M. Mikelonis, Katherine Ratliff, Sungmin Youn

All Engineering Faculty Research

Development of numerical models to predict stormwater-mediated transport of pathogenic spores in the environment depends on an understanding of adhesion forces that dictate detachment after rain events. Zeta potential values were measured in the laboratory for Bacillus globigii and Bacillus thuringiensis kurstaki, two common surrogates used to represent Bacillus anthracis, in synthetic baseline ultrapure water and laboratory prepared stormwater. Zeta potential curves were also determined for materials representative of urban infrastructure (concrete and asphalt). These data were used to predict the interaction energy between the spores and urban materials using Derjaguin-Landau-Verwey-Overbeek (DLVO) modeling. B. globigii and B. thuringiensis kurstaki …