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Articles 21451 - 21480 of 198089

Full-Text Articles in Engineering

A Joint Operation Mode Of Multi-Production Wells For Deep Geothermal Water Exploitation, Ping Yu, Li Fang, Ji Wenqing, Yuan Xiaoying, Qi Yufeng, Deng Xiaoying, Wang Xinyi Jan 2024

A Joint Operation Mode Of Multi-Production Wells For Deep Geothermal Water Exploitation, Ping Yu, Li Fang, Ji Wenqing, Yuan Xiaoying, Qi Yufeng, Deng Xiaoying, Wang Xinyi

Coal Geology & Exploration

Deep geothermal water, a type of clean and low-carbon renewable energy, plays a significant role in achieving the goals of peak carbon dioxide emissions and carbon neutrality. However, its irrational exploitation will lead to many problems such as decreased water quantity, lowered water level, and low engineering benefits. Based on the available exploration data of geothermal wells in the urban area of Kaifeng City, Henan Province, this study constructed a hydrogeological model used to characterize the migration of geothermal water and a corresponding mathematical model, which was identified and verified using the Galerkin finite element method. Focusing on geothermal reservoirs …

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Evaluating The Exploitation And Utilization Prospects Of Hot Dry Rock In Bohai Bay Basin: Understanding Based On Numerical Simulations For Exploitation Optimization, Jiang Xiaoxue, Zhu Chuanqing, Ding Rui, Xie Fang, Qiu Nansheng Jan 2024

Evaluating The Exploitation And Utilization Prospects Of Hot Dry Rock In Bohai Bay Basin: Understanding Based On Numerical Simulations For Exploitation Optimization, Jiang Xiaoxue, Zhu Chuanqing, Ding Rui, Xie Fang, Qiu Nansheng

Coal Geology & Exploration

The Bohai Bay Basin, characterized by high terrestrial heat flow, formation temperatures average of 175℃ at a depth of 5000 m, and reservoirs with lithologies dominated by low-porosity and low-permeability metamorphic and igneous rocks, meets the requirements for the formation of hot dry rock (HDR) resources. Based on geothermal parameters such as terrestrial heat flow, rock thermal conductivity, and heat production rate, this study established a three-dimensional HDR exploitation model with thermo-hydro coupling using the COMSOL software. Furthermore, this study analyzed the effects of spacing between production and reinjection wells, reinjection and production rates, and well arrangement mode on the …

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Influencing Patterns Of Multiple Factors On The Heat Transfer Performance Of Moderately Deep Geothermal Wells, Han Yongliang, Wang Kaipeng, Wang Yijie, Gou Li, Yang Yanbin, Lei Yanzi, Wu Fangli, Shen Hao Jan 2024

Influencing Patterns Of Multiple Factors On The Heat Transfer Performance Of Moderately Deep Geothermal Wells, Han Yongliang, Wang Kaipeng, Wang Yijie, Gou Li, Yang Yanbin, Lei Yanzi, Wu Fangli, Shen Hao

Coal Geology & Exploration

Vigorously promoting the technology for heating using moderately deep geothermal energy serves as an important measure for China’s pursuit of carbon neutrality and peak carbon dioxide emissions. A coaxial double-pipe heat transfer system for moderately deep geothermal wells can avoid damage to groundwater resources and the environment. Furthermore, the influencing factors of the wells exhibit complicated and nonlinear interactions. Based on the theoretical analysis and mathematical description of a moderately deep well with a coaxial double-pipe heat exchanger, this study established a layered heat transfer model for the geothermal well and verified its reliability. This study investigated a moderately deep …

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Effects Of Fracture Distribution On Heat Extraction Through Co2-Egs, Zhou Qing, Liao Jianxing, Xu Bin, Yao Liang, Zhou Haoyu, Zhao Quan Jan 2024

Effects Of Fracture Distribution On Heat Extraction Through Co2-Egs, Zhou Qing, Liao Jianxing, Xu Bin, Yao Liang, Zhou Haoyu, Zhao Quan

Coal Geology & Exploration

Geothermal energy, a promising source of renewable energy, has attracted considerable attention. In deep geothermal reservoirs, complex fracture networks formed by artificial stimulation provide predominant channels for heat extraction. Therefore, the spatial distribution of fractures directly affects the heat extraction efficiency. This study aims to explore the effects of different spatial distributions of fractures on the heat recovery performance. Based on the fracture network following a power-law distribution, this study systematically investigated the effects of the fracture network with different values of fracture length index (a) and density (β) on the heat recovery performance of a …

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Unveiling Efficiency: Investigating Distance Measures In Wastewater Treatment Using Interval-Valued Neutrosophic Fuzzy Soft Set, Muhammad Saeed, Kinza Kareem, Fatima Razzaq, Muhammad Saqlain Jan 2024

Unveiling Efficiency: Investigating Distance Measures In Wastewater Treatment Using Interval-Valued Neutrosophic Fuzzy Soft Set, Muhammad Saeed, Kinza Kareem, Fatima Razzaq, Muhammad Saqlain

Neutrosophic Systems with Applications

To reduce the threats that wastewater poses to human health and the environment, water treatment techniques must be improved. The use of a procedure that includes preparation, testing, primary and secondary treatments, filtration, disinfection, and continuous monitoring is therefore required. The objective of this research is to create a hybrid notion that extends the idea of an interval-valued neutrosophic fuzzy soft set (IVNFSS) to an interval-valued neutrosophic fuzzy set. Operations like complement, union, and integration are included in the idea. To improve decision-making accuracy, a quality-assessment distance measure is incorporated, offering a numerical representation of the disparity between various factors. …

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Table Of Contents, The Editors Jan 2024

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Major Challenges Of Deep Geothermal Systems And An Innovative Development Mode Of Regs Integrated With Energy Storage, Hou Zhengmeng, Wu Xuning, Luo Jiashun, Zhang Liehui, Li Zaoyuan, Cao Cheng, Wu Lin, Chen Qianjun Jan 2024

Major Challenges Of Deep Geothermal Systems And An Innovative Development Mode Of Regs Integrated With Energy Storage, Hou Zhengmeng, Wu Xuning, Luo Jiashun, Zhang Liehui, Li Zaoyuan, Cao Cheng, Wu Lin, Chen Qianjun

Coal Geology & Exploration

China has long been a global leader in the direct utilization of moderate- to low-temperature geothermal energy, in contrast to its sluggish progress in power generation using deep geothermal energy. Rocks in deep reservoirs exhibit decreased permeability under high-temperature and high-pressure conditions, necessitating the establishment of engineered geothermal system (EGS) for the exploitation of deep geothermal energy. In an EGS, hydraulic fracturing is employed for reservoir stimulation to create artificially enhanced geothermal reservoirs with higher permeability. The current techniques for deep geothermal reservoir stimulation are predominantly borrowed from hydraulic fracturing processes employed in the oil and gas sector, placing limitations …

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Dating Methods For Travertine And Siliceous Sinter In Geothermal Systems: Progress And Applications, Li Bin, Li Yiman, Pang Zhonghe, Huang Tianming, Gao Binbin Jan 2024

Dating Methods For Travertine And Siliceous Sinter In Geothermal Systems: Progress And Applications, Li Bin, Li Yiman, Pang Zhonghe, Huang Tianming, Gao Binbin

Coal Geology & Exploration

Sinters of geothermal system are usually dominated by travertine and siliceous sinter. With rich information on multi-temporal and spatial scales, they can be used to restore paleohydrological and paleoclimatic histories, reconstruct the evolutionary process of regional hydrothermal activity, and constrain tectonic modes. Accurate dating of sinters is the basis of relevant researches. Common dating methods include radiocarbon dating (based on inorganic and organic carbon), uranium series disequilibrium dating, cosmogenic nuclide dating, optically stimulated luminescence (OSL) dating, and electron spin resonance dating. Radiocarbon dating has primarily used for the dating of hot-spring sinters in China, followed by electron spin resonance dating …

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Thermal Conductivity Column Of Rocks And Distribution Characteristics Of Paleo-Geothermal Field In The Songliao Basin, Tang Boning, Qiu Nansheng, Zhu Chuanqing, Chang Jian, Li Xiao, Huang Yue, Yang Junsheng, Fu Xiuli Jan 2024

Thermal Conductivity Column Of Rocks And Distribution Characteristics Of Paleo-Geothermal Field In The Songliao Basin, Tang Boning, Qiu Nansheng, Zhu Chuanqing, Chang Jian, Li Xiao, Huang Yue, Yang Junsheng, Fu Xiuli

Coal Geology & Exploration

The paleo-geothermal field of a basin is closely related to the formation and evolution of geothermal, oil, and gas resources. To ascertain the characteristics of the paleo-geothermal field in the Songliao Basin during some critical periods, this study established the thermal conductivity column of rocks in the basin using measurements from 269 samples and compiled previous data. Then, it simulated the burial and thermal histories of multiple wells under the constraint of vitrinite reflectance (Rran). The results indicate that the thermal conductivity of the Songliao Basin increases with the depth, with increasing rates higher in the upper …

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Characteristics And Genetic Mechanism Of Geothermal Reservoirs In The Neogene Guantao Formation, Qikou Sag, Xia Guochao, Lou Da, Zhao Yanting, Wang Hui, Duan Zhongfeng, Sun Xiaolin, Zhang Feipeng, Luo Rong, Ge Jiacheng Jan 2024

Characteristics And Genetic Mechanism Of Geothermal Reservoirs In The Neogene Guantao Formation, Qikou Sag, Xia Guochao, Lou Da, Zhao Yanting, Wang Hui, Duan Zhongfeng, Sun Xiaolin, Zhang Feipeng, Luo Rong, Ge Jiacheng

Coal Geology & Exploration

The Qikou Sag in the Huanghua Depression, Bohai Bay Basin boasts extremely abundant geothermal resources. Among them, the geothermal reservoirs of the Neogene Guantao Formation have the greatest potential for exploitation. To ascertain the properties of geothermal resources in this formation and rationally exploit these resources, it is significant to investigate the geothermal field, porosity, permeability, geothermal water circulation patterns, and genetic mode of geothermal reservoirs in the formation. Based on data from drilling, geophysical exploration, thermometry, and production of the study area, this study determined that the geothermal reservoirs of the Guantao Formation in the Qikou Sag constitute a …

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Hydrochemistry Characteristics And Genesis Mode Of Hot Springs In The Luolou River Basin, Yunnan, China, Luo Huan, Liu Zhennan, Ma Yiqi, Zhang Yunhui, Tao Lanchu, Chen Qingsong, Fu Dunkai, Wu Xiangchuan Jan 2024

Hydrochemistry Characteristics And Genesis Mode Of Hot Springs In The Luolou River Basin, Yunnan, China, Luo Huan, Liu Zhennan, Ma Yiqi, Zhang Yunhui, Tao Lanchu, Chen Qingsong, Fu Dunkai, Wu Xiangchuan

Coal Geology & Exploration

The hydrochemistry and genesis mechanism of thermal springs hold great significance for the exploitation and utilization of low to intermediate temperature geothermal resources. Under the influence of a concealed fault zone, thermal springs in the Luolou River basin, Yunnan Province, are distributed along both sides of valleys and exposed in Quaternary loose deposits and Permian basalt strata. It belongs to low to intermediate temperature thermal spring water, with temperatures ranging between 34.5 and 50.0℃, pH is between 7.62-9.73, TDS is between 262-702 mg/L. Based on the hydrochemical and isotopic tests of thermal spring samples and nearby cold water samples from …

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Long-Term Operation Performance Of Medium-Deep Borehole Heat Exchangers In The Guanzhong Area, Zhang Zhibin, Ma Zhendi, Hao Jianke, Jia Guosheng, Ke Tingting, Cheng Chonghua, Jin Liwen Jan 2024

Long-Term Operation Performance Of Medium-Deep Borehole Heat Exchangers In The Guanzhong Area, Zhang Zhibin, Ma Zhendi, Hao Jianke, Jia Guosheng, Ke Tingting, Cheng Chonghua, Jin Liwen

Coal Geology & Exploration

Technologies for heating utilizing medium-deep geothermal energy exhibit promising application prospects in the Guanzhong area of China, which boasts abundant geothermal resources. Geological parameters serve as determining factors in the performance of medium-deep borehole heating systems. This study aims to explore the performance of medium-deep borehole heating systems in the Guanzhong area, Shaanxi Province. First, this study analyzed the geological parameters of five typical areas in Guanzhong: Xingping City under the jurisdiction of Xianyang City, Weicheng District of Xianyang, and Gaoling, Huyi, and Chang’an districts of Xi’an City. Then, by combining the typical structural parameters of buried pipes, this study …

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Influencing Factor Analysis And Optimization Of Heat Extraction Performance Of Moderately Deep Coaxial Borehole Heat Exchangers In Northern Shaanxi, China, Zou Haijiang, Li Yongpeng, Zhang Lin, Hui Peng, Liu Houning, Shen Fang, Wang Fenghao Jan 2024

Influencing Factor Analysis And Optimization Of Heat Extraction Performance Of Moderately Deep Coaxial Borehole Heat Exchangers In Northern Shaanxi, China, Zou Haijiang, Li Yongpeng, Zhang Lin, Hui Peng, Liu Houning, Shen Fang, Wang Fenghao

Coal Geology & Exploration

The geothermal heating technology utilizing moderately deep coaxial borehole heat exchangers (MDCBHEs) has emerged and found extensive applications in urban heating in northern China. Despite abundant geothermal resources, northern Shaanxi exhibits slightly low geothermal gradients and distinct thermophysical properties of rocks and soils. Therefore, geological parameters influence the heat transfer performance of MDCBHEs in this area. Using OpenGeoSys, an open-source numerical simulation platform, this study established a three-dimensional calculation model for heat transfer between a MDCBHE and surrounding strata. Based on typical geological parameters in northern Shaanxi, the study investigated the influence of various design parameters on the heat transfer …

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Statistical Analysis Of The Spatial Distribution And Genesis Of Lithium In Geothermal Water In The Yangbajing-Gulu Rift, Xizang, Chen Yakui, Kong Yanlong, Duan Jiabin, Sun Wenjie, Cheng Yuanzhi Jan 2024

Statistical Analysis Of The Spatial Distribution And Genesis Of Lithium In Geothermal Water In The Yangbajing-Gulu Rift, Xizang, Chen Yakui, Kong Yanlong, Duan Jiabin, Sun Wenjie, Cheng Yuanzhi

Coal Geology & Exploration

In the Yangbajing-Gulu rift, located in Xizang, the lithium concentration in geothermal water exceeds the average level of thermal springs in Xizang. However, the hydrochemical genesis of lithium in geothermal water in this rift remains controversial, and one primary reason for this is the unclear spatial distribution pattern of lithium. Common methods for analyzing spatial distribution patterns include Ordinary Kriging and CO-Kriging. Nevertheless, the former suffers low precision. For the latter, it is difficult to obtain suitable auxiliary variables. Given this, this study determined two auxiliary variables: (1) the Cl− concentration, a physicochemical parameter exhibiting the strongest correlation with …

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Adversarial Robustness With Partial Isometry, Loic Shi-Garrier, Nidhal Carla Bouaynaya, Daniel Delahaye Jan 2024

Adversarial Robustness With Partial Isometry, Loic Shi-Garrier, Nidhal Carla Bouaynaya, Daniel Delahaye

Henry M. Rowan College of Engineering Departmental Research

Despite their remarkable performance, deep learning models still lack robustness guarantees, particularly in the presence of adversarial examples. This significant vulnerability raises concerns about their trustworthiness and hinders their deployment in critical domains that require certified levels of robustness. In this paper, we introduce an information geometric framework to establish precise robustness criteria for (Formula presented.) white-box attacks in a multi-class classification setting. We endow the output space with the Fisher information metric and derive criteria on the input–output Jacobian to ensure robustness. We show that model robustness can be achieved by constraining the model to be partially isometric around …

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Characterization Of Functionalized Nanoparticle Coatings Subjected To Soiling And Cementation, Fuad Behbudov Jan 2024

Characterization Of Functionalized Nanoparticle Coatings Subjected To Soiling And Cementation, Fuad Behbudov

Student Theses and Dissertations

This thesis investigates the efficacy of functionalized nanoparticle coatings in reducing soiling and cementation on solar panels. Employing cementation cycles with Arizona Test Dust (ATD) and Arabian American Oil Company (ARAMCO) dust, the study examines the impact of these coatings under simulated environmental conditions. Key analyses include water contact angle (WCA), transmittance, and X-ray Photoelectron Spectroscopy (XPS). Results show that methylated coatings significantly enhance hydrophobicity and maintain higher transmittance, suggesting less frequent cleaning and sustained effectiveness. The study noted a considerable variation in WCA post-cementation, particularly a marked decrease for the lighting sample, signifying a notable chemical alteration on the …

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Efficacy Of Rice Husk Ash (Rha) And Hydrated Lime As Stabilizing Agents For Poor Subgrade Soils In Arkansas, Fares Tarhuni Jan 2024

Efficacy Of Rice Husk Ash (Rha) And Hydrated Lime As Stabilizing Agents For Poor Subgrade Soils In Arkansas, Fares Tarhuni

Student Theses and Dissertations

Rice husk is controlled-burned farm waste. Ash is rich in silicate, a pozzolanic material that improves soil. Rice Husk Ash (RHA) and Hydrated lime (HL) are tested as soil stabilizers in Arkansas' poor subgrade soils. This study analyzes two local subgrade soils with different RHA (3, 6, and 9%), HL (1, 3, and 5%), and RHA (3, 4, or 5%) plus 1%HL. Its goal is to discover the ideal percentages of RHA, HL, or a combination treated soils were tested for Atterberg limits, Modified Proctor, pH, CBR, UCS, and Free Swell. In testing, RHA and HL reduced soil plasticity and …

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Employing Frequency Independent Structure For Ultra-Wide Band Antenna, Hassan Ali Ragheb, Mostafa Salah Jan 2024

Employing Frequency Independent Structure For Ultra-Wide Band Antenna, Hassan Ali Ragheb, Mostafa Salah

Electrical Engineering

The paper presents a novel and compact design for an ultra-wideband antenna based on frequency independent ethos. It consists of a Log-Periodic monopole structure with specific angle for the radiating patch with a defected ground plane. The antenna is fed using microstrip line feed and is designed on an FR4 substrate with a thickness of 1.6 mm, a relative permittivity of 4.4, and a loss tangent of 0.02. The Finite Element Method (FEM) of the Ansoft HFSS software is used during the design process. The proposed antenna covers the frequency range from 5.3 GHz up to 14 GHz for multiple …

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Control And Estimation Of Unmanned Aerospace Vehicles In The Presence Of Constraints And Dynamic Uncertainties, Abhijit Dongare Jan 2024

Control And Estimation Of Unmanned Aerospace Vehicles In The Presence Of Constraints And Dynamic Uncertainties, Abhijit Dongare

Dissertations - ALL

In the first part of this dissertation, we consider the control of autonomous systems in the presence of pointwise-in-time state and control constraints. Firstly, we propose the attitude and pointing control of a rigid body in the presence of constraints. Artificial potentials are used to achieve desired tracking and avoid pointing direction constraints. The proposed control law ensures the asymptotic convergence to the desired attitude and pointing direction. Additionally, the control of driftless control-affine systems is also considered. The feedback system converges in a stable manner to the desired safe set in the state space, while avoiding the unsafe exclusion …

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Unmanned Aerial Systems (Uas) Traffic Density Prediction And Multi-Agent Task Allocation, Chen Luo Jan 2024

Unmanned Aerial Systems (Uas) Traffic Density Prediction And Multi-Agent Task Allocation, Chen Luo

Dissertations - ALL

In recent years, the field of Multi-Agent Systems (MAS) has garnered increasing attention. The essence of Multi-Agent Systems lies in orchestrating the coordination and collaboration of autonomous agents, endowing them with the ability to work collectively towards common goals. This characteristic makes MAS particularly germane in addressing the challenges posed by complex and dynamic environments, where theadaptability and decentralized decision-making of autonomous agents prove advantageous. To delve into the intricacies of MAS, three primary research directions have emerged. Firstly, we aim to develop a model rapidly and accurately to forecast future Unmanned Aerial Systems (UAS) traffic density patterns while simultaneously …

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Liquefaction Hazard Analysis Of Northeast Arkansas Using Cone Penetration Test Data, Rupesh Mahat Jan 2024

Liquefaction Hazard Analysis Of Northeast Arkansas Using Cone Penetration Test Data, Rupesh Mahat

Student Theses and Dissertations

The presence of seismically active New Madrid Seismic Zone puts Northeast Arkansas at seismic hazard. The deep soft sediments of Northeast Arkansas within the Mississippi Embayment put the region at liquefaction risk. One hundred and thirty-one (131) Cone Penetration Test (CPT) data are used for liquefaction assessments. Liquefaction analysis on 20 m of surficial deposits is analyzed and compared. Sensitivity and parametric study are also conducted. Geographical Information System (GIS) maps based on liquefaction potential indices are generated. Contour maps of liquefaction potentials are developed for Mississippi County. Liquefaction varies spatially in Northeast Arkansas. A full 20 m of soil …

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Power Grid Resiliency Enhancement Against Flood-Induced Hazards, Mohadese Movahednia Jan 2024

Power Grid Resiliency Enhancement Against Flood-Induced Hazards, Mohadese Movahednia

LSU Doctoral Dissertations

Natural disasters, such as floods, may damage power system assets and lead to widespread and long outages. The impact of flood can be alleviated by preventive actions such as installing tiger dams around power substations before the flood. In this regard, it is imperative that critical substations are identified in terms of the connected load and imposed costs to the system. This study presents a resource allocation approach for protecting power substations against flood events a day ahead of the event. First, the required information for the model is extracted. Flood probability distribution functions are used to generate several flood …

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Exploring The Electrochemical Performance Of Calcium-Ion Batteries With Novel Cathodes And Electrolytes, Paul Alexis Chando Jan 2024

Exploring The Electrochemical Performance Of Calcium-Ion Batteries With Novel Cathodes And Electrolytes, Paul Alexis Chando

Dissertations - ALL

The development of electric vehicles and energy storage devices are part of larger international efforts to create a sustainable future. Lithium-ion batteries have become crucial components to powering these technologies. However, the growing dependence of this singular battery chemistry to power an ever expanding landscape of technologies raises sustainability issues around lithium. Exploration of alternate battery chemistries have become part of research efforts to meet global energy demands. Calcium has emerged as one such battery system that could help alleviate stresses placed on lithium with its energy density and cost. Battery chemistries are unique, and each battery possesses its own …

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No Difference In Pullout Strength Between A Bio-Inductive Implant And A Semitendinosus Tendon Graft In A Biomechanical Study Of Medial Patellofemoral Ligament Repair Augmentation, Austin Wetzler, Sean Mcmillan, Erik Brewer, Aakash Patel, Samuel Handy, Merrick Wetzler Jan 2024

No Difference In Pullout Strength Between A Bio-Inductive Implant And A Semitendinosus Tendon Graft In A Biomechanical Study Of Medial Patellofemoral Ligament Repair Augmentation, Austin Wetzler, Sean Mcmillan, Erik Brewer, Aakash Patel, Samuel Handy, Merrick Wetzler

Rowan-Virtua School of Translational Biomedical Engineering & Sciences Departmental Research

Purpose: To compare the pullout strength of a bio-inductive implant (BI) used to augment a medial patellofemoral ligament (MPFL) repair with the pullout strength of semitendinosus graft in a biomechanical cadaveric model. Methods: Six matched pairs of cadavers (12 knees) were used in the biomechanical testing comparing semitendinosus tendon (Semi-T) versus a BI. The Semi-T was harvested from 1 of the matched pairs. A standard double-bundle technique using 2 sockets in the upper two-thirds of the patella 15 mm apart was performed. After docking of the graft into the patella, the patella was dissected free of soft tissues and potted …

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Surface Modification Of Poly(4,4'-Oxydiphenilene Pyromellitimide) With Low-Pressure Plasma Treatment, Cihan Aktas Jan 2024

Surface Modification Of Poly(4,4'-Oxydiphenilene Pyromellitimide) With Low-Pressure Plasma Treatment, Cihan Aktas

USF Tampa Graduate Theses and Dissertations

This study explores the change of the wetting characteristics of commercially availablepolyimide (PI), Kapton® HN, films a type of poly(4,4′-oxydiphenylene-pyromellitimide), following treatment with low-pressure plasmas of carbon tetrafluoride (CF4), air, hydrogen (H2), carbon-dioxide (CO2) and oxygen (O2) gases as well as the surface texturing via laser-exposure procedure. The water contact angle (CA) and surface free energy (SFE) of untreated PI films were determined as 82.4°±0.8 and 45.0±0.3 mN/m, respectively. After CF4 plasma gas treatment, the CA value of PI films increased to 110.2°±1.0, while it decreased to 9.3°±2.3 after O2 plasma gas treatment. The surface free energy (SFE) of PI …

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Data-Driven Control Of Acoustic Waves Using Movable And Flexible Scatterers, Noam Smilovich Jan 2024

Data-Driven Control Of Acoustic Waves Using Movable And Flexible Scatterers, Noam Smilovich

Master's Theses

Partial Differential Equations (PDEs) serve as fundamental tools in scientific and engineering disciplines, modeling phenomena ranging from material design to climate dynamics. Developing robotic systems capable of controlling PDE-governed systems, particularly when these phenomena are only partially observable, has the potential to drive significant technological advancements. This work presents a framework that leverages physics-informed machine learning (ML) for the control of PDEs. At the core of this approach is an agent equipped with sensors that generate a low-dimensional, physics-informed representation of the environment, enabling the derivation of optimal sparse control policies for the agent’s actuators. The focus is on manipulating …

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Application Of Learning Processes For Improving Last-Mile Logistics Optimization At Scale, Seyedeh Shaghayegh Rabbanian Jan 2024

Application Of Learning Processes For Improving Last-Mile Logistics Optimization At Scale, Seyedeh Shaghayegh Rabbanian

LSU Doctoral Dissertations

The escalating demands of omnichannel retailing, rapid urbanization and shifting customer behaviors have propelled last-mile vehicle routing logistics to the forefront of research. This last-mile phase, recognized as a significant contributor to costs and pollution in the supply chain, necessitates efficient route optimization to minimize expenses and environmental impact. This research delves into machine learning based techniques for solving large-scale Vehicle Routing Problem (VRP), a fundamental concern in last-mile logistics, aiming to optimize delivery vehicle routing amidst diverse customer nodes and operational constraints. Three primary research subproblems are analyzed: utilizing machine learning for constructive solutions, Variable Neighborhood Search (VNS) metaheuristic, …

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Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain Jan 2024

Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain

Theses and Dissertations

This abstract highlight the significant findings and contributions of the study, which aimed to develop model clauses specifically tailored to the Egyptian construction industry for multi-party construction contracts. The research methodology encompassed several key components. Firstly, a comprehensive literature review was conducted to explore the various construction delivery methods prevalent in Egypt. This review provided a solid foundation for understanding the existing practices and identifying areas for improvement. The study also delved into the concept of Integrated Project Delivery (IPD) and its potential benefits as well as an analysis of the commonly used standard forms of contract and successful case …

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Cubesat Reaction Wheel Attitude Control Platform System Architecture, Justin Hartland Jan 2024

Cubesat Reaction Wheel Attitude Control Platform System Architecture, Justin Hartland

Beyond: Undergraduate Research Journal

In the classroom, physics behind spacecraft attitude dynamics and controls is abstract and difficult to comprehend. It is common that students struggle to develop the connection between the math they learn and how it can be applied in the real world. The goal of this project is to design and manufacture a 1U, 3U, and 6U CubeSat testbed for autonomous control systems utilizing reaction wheels. The testbed will include three separate reaction wheels each mounted on its own respective axis to control the attitude in 3 degrees of freedom. The end goal of the CubeSat Control Platform is to be …

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Enhancing The Tribological Performance Of Prosthetic Implants: An Investigation Of Cnc Surface Micro-Texturing On Uhmwpe, Javier Ortega, J. Perez, N. Perez Jan 2024

Enhancing The Tribological Performance Of Prosthetic Implants: An Investigation Of Cnc Surface Micro-Texturing On Uhmwpe, Javier Ortega, J. Perez, N. Perez

Research Symposium

Background: Annually, there are over a million joint replacement procedures and more than 250,000 revision surgeries in the United States. The typical lifespan of a joint replacement ranges from 7 to 15 years, often curtailed by complications such as excessive implant wear leading to infections and joint dislocations. Given that most joint replacement recipients are between the ages of 50 and 70, the later part of their lives is often marred by repeated surgeries and discomfort. Presently, the predominant material used in joint replacements is medical-grade Ultra-High Molecular Weight Polyethylene (UHMWPE) with smooth surfaces. While these smooth surfaces are believed …

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