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Articles 18871 - 18900 of 196425

Full-Text Articles in Engineering

A Data-Driven Framework To Inform Sustainable Management Of Animal Manure In Rural Agricultural Regions Using Emerging Resource Recovery Technologies, Mohammed T. Zaki, Lewis Stetson Rowles, Jeff Hallowell, Kevin D. Orner Apr 2024

A Data-Driven Framework To Inform Sustainable Management Of Animal Manure In Rural Agricultural Regions Using Emerging Resource Recovery Technologies, Mohammed T. Zaki, Lewis Stetson Rowles, Jeff Hallowell, Kevin D. Orner

Civil Engineering & Construction: Faculty Publications

Thermochemical conversion technologies are emerging as preferred resource recovery practices for managing animal manure in agricultural regions. Although the implementation of such technologies has been previously studied, difficulties exist in maintaining balance between high rate of resource recovery and low environmental, economic, and social impacts, particularly in rural regions with limited resources. We developed a data-driven framework by integrating machine learning with life cycle thinking that can be used as an open-source tool to help overcome these barriers. The framework was applied to compare two emerging technologies: pyrolysis versus hydrothermal carbonization for managing the excess poultry litter in a rural …


Methods For Finding Best Coset Codes For Physical-Layer Security, Andrew Glenn Swain Apr 2024

Methods For Finding Best Coset Codes For Physical-Layer Security, Andrew Glenn Swain

Theses and Dissertations

Finding best coset codes for secrecy over the binary erasure wiretap channel remains a difficult problem. Greater understanding of the structure of coset codes is necessary to reduce the problem space in which we search for these best codes. This dissertation presents new necessary conditions for a code to be best, including a condition that states that a code must maximize the minimum distance of both itself and its dual. It introduces and evaluates the accuracy of new heuristics to approximate the code's equivocation based on a code's weight enumerator polynomial. We also present a new tool for visualizing the …


Predicted Strength And Ductility Of Roof Truss Diaphragms With Tension-Only Rod Bracing And Hillside Washer Rod Connections, Emma Jean Brown Apr 2024

Predicted Strength And Ductility Of Roof Truss Diaphragms With Tension-Only Rod Bracing And Hillside Washer Rod Connections, Emma Jean Brown

Theses and Dissertations

Metal buildings with roof truss diaphragms and tension-only rod bracing are a common structural system for single story industrial and commercial buildings. Despite the widespread use of metal building diaphragms in modern construction, there is limited knowledge on their strength and ductility under seismic loads. In this study, finite element models of diaphragm subassemblies and a full-size diaphragm were created to determine the strength and ductility of metal building diaphragms with tension-only rod bracing using hillside washer rod connections. Finite element models of two-tier diaphragm specimens that had been previously tested in the laboratory were created. Girders and purlins were …


Advancing Brain Tumor Segmentation With Spectral–Spatial Graph Neural Networks, Sina Mohammadi, Mohamed Allali Apr 2024

Advancing Brain Tumor Segmentation With Spectral–Spatial Graph Neural Networks, Sina Mohammadi, Mohamed Allali

Engineering Faculty Articles and Research

In the field of brain tumor segmentation, accurately capturing the complexities of tumor sub-regions poses significant challenges. Traditional segmentation methods usually fail to accurately segment tumor subregions. This research introduces a novel solution employing Graph Neural Networks (GNNs), enriched with spectral and spatial insight. In the supervoxel creation phase, we explored methods like VCCS, SLIC, Watershed, Meanshift, and Felzenszwalb–Huttenlocher, evaluating their performance based on homogeneity, moment of inertia, and uniformity in shape and size. After creating supervoxels, we represented 3D MRI images as a graph structure. In this study, we combined Spatial and Spectral GNNs to capture both local and …


Radiative Cooling For Energy-Efficient Power Generation, Rickia Hanna Apr 2024

Radiative Cooling For Energy-Efficient Power Generation, Rickia Hanna

Celebrating Scholarship and Creativity Day (2018-)

This thesis examined radiative cooling on a small scale using a hybrid photovoltaic/radiative cooling model system, to determine its efficiency for large-scale power generation. Radiative cooling is concerned with heat transfer and this thesis’s main goal is to harness that heat energy to produce electricity. The efficiency of the system was tested using various light sources at different angles and total power output. The testing was done several times and there proved to be a proportional relationship between light intensity and current output. However, due to the performance threshold of the PTEC module, the component of the system used to …


Critical Raw Material In Mineral Elements Found In Fly Ashes From The Czech Republic Power Plant, Agnieszka Klupa Apr 2024

Critical Raw Material In Mineral Elements Found In Fly Ashes From The Czech Republic Power Plant, Agnieszka Klupa

Journal of Sustainable Mining

The economic development of EU countries is limited due to limited access to a number of mineral raw materials, which necessitates actions aimed at securing the supply of CRM. For this reason, CRMs constitute elements of particular importance for the EU. The aim of the study was to assess the content of CRMs as a potential source of REY in fly ash resulting from the coal combustion in one of the power plants in the Czech Republic. In the tested ash the main phases are: glassy phase, mullite and quartz. The chemical composition of the tested fly ashes showed dominance …


Ferroresonance In Three-Phase Electrical Networks, Shavkat Ernstovich Begmatov Apr 2024

Ferroresonance In Three-Phase Electrical Networks, Shavkat Ernstovich Begmatov

Technical science and innovation

Possible modes of ferroresonance in three-phase electric networks and analysis of substitution schemes where ferroresonance voltage increase is observed are considered. The most complete magnetization curve of the transformer core and the analysis of the generalized equivalent substitution scheme are presented, as a result of which more accurate formulas for determining the values of equivalent parameters of the electrical network and voltage transformer in ferroresonance mode are obtained. Factor of ferroresonance voltage increase is introduced, which determines ratio between amplitude values of transformer phase voltage and mains voltage. The method of determination of boundary conditions of steady ferroresonance voltage increase …


Main Prospects Of Natural Gas Purification Technologies From Acidic Compounds, Oybek Yusupdjanovich Aripdjanov, Diyora Zokhid Qizi Khayrullaeva, Jonibek Avazek Ogli Abdumuminov Apr 2024

Main Prospects Of Natural Gas Purification Technologies From Acidic Compounds, Oybek Yusupdjanovich Aripdjanov, Diyora Zokhid Qizi Khayrullaeva, Jonibek Avazek Ogli Abdumuminov

Technical science and innovation

The article discusses the main prospects for the technology of purifying natural gas from acidic components and the problems of ensuring the purity of oil and gas products in accordance with state standards. An increase in the degree of purification from H2S, CO2, elemental sulfur, carbonyl sulfide, ethyl mercaptans (thiols), methyl mercaptan, carbon disulfide, sulfides, disulfides (dithioethers), thiophene, sulfoxides and sulfones is considered. Also, the physicochemical properties of the absorbent for the purification of sulfur compounds (generated during natural gas processing) are studied. Based on the study of various absorbents (ethanolamine (EA), methylethanolamine (MEA), diethanolamine (DEA), …


Development Of An E-Governance Solution For Process Safety Management (Psm) Compliance, Dheerajkumar R Narang Apr 2024

Development Of An E-Governance Solution For Process Safety Management (Psm) Compliance, Dheerajkumar R Narang

Harrisburg University Experiential Learning Projects

E-governance (digital solutions) is the new norm in delivering numerous government services from government to citizens, businesses, institutions, and even other governments across all industry segments. One important application of digital solutions, in the governance space, can potentially be to comprehensively audit and intermittently monitor compliance of process plants with the regional process safety management (PSM) regulations. This presentation unveils the idea of an e-governance PSM solution that will potentially enable the relevant regulatory bodies around the world to seamlessly monitor and intermittently audit the process safety management (PSM) compliance through a digital solution. The presentation builds on an earlier …


Modeling The Human Learning Process Using An Industrial Steam Boiler Analogy To Design A Psychophysiological-Based Hypermedia Adaptive Automation System, Liliana María Villavicencio López Apr 2024

Modeling The Human Learning Process Using An Industrial Steam Boiler Analogy To Design A Psychophysiological-Based Hypermedia Adaptive Automation System, Liliana María Villavicencio López

USF Tampa Graduate Theses and Dissertations

This dissertation aims to address the existing gap in the integration of various dimensions within the student learning system, encompassing cognitive, emotional, and physical variables. The primary objective is to construct a Personalized Learning Adaptive Automation model using Electroencephalography (EEG) technology.

To provide deeper insight into the intricate nature of the Human Learning Process, this study introduces a novel analogy with an Industrial Steam Boiler. This analogy serves as a distinctive contribution to research in the field.

The research methodology involved the collection of brainwaves data from engineering students while they undertook educational tasks of varying levels of difficulty, categorized …


Achieving Room Temperature Plasticity In Brittle Ceramics Through Elevated Temperature Preloading, Chao Shen, Jin Li, Tongjun Niu, Jaehun Cho, Zhongxia Shang, Yifan Zhang, Anyu Shang, Bo Yang, Ke Xu, R. Edwin Garcia, Haiyan Wang, Xinghang Zhang Apr 2024

Achieving Room Temperature Plasticity In Brittle Ceramics Through Elevated Temperature Preloading, Chao Shen, Jin Li, Tongjun Niu, Jaehun Cho, Zhongxia Shang, Yifan Zhang, Anyu Shang, Bo Yang, Ke Xu, R. Edwin Garcia, Haiyan Wang, Xinghang Zhang

Purdue University Libraries Open Access Publishing Fund

Ceramic materials with high strength and chemical inertness are widely used as engineering materials. However, the brittle nature limits their applications as fracture occurs before the onset of plastic yielding. There has been limited success despite extensive efforts to enhance the deformability of ceramics. Here we report a method for enhancing the room temperature plastic deformability of ceramics by artificially introducing abundant defects into the materials via preloading at elevated temperatures. After the preloading treatment, single crystal (SC) TiO2 exhibited a substantial increase in deformability, achieving 10% strain at room temperature. SC α-Al2O3 also showed plastic deformability, 6 to 7.5% …


Acoustothermal Transfection For Cell Therapy, Xiufang Liu, Ning Rong, Zhenhua Tian, Joseph Rich, Lili Niu, Pengqi Li, Laixin Huang, Yandai Dong, Wei Zhou, Pengfei Zhang, Yizhao Chen, Congzhi Wang, Long Meng, Tony Jun Huang, Hairong Zheng Apr 2024

Acoustothermal Transfection For Cell Therapy, Xiufang Liu, Ning Rong, Zhenhua Tian, Joseph Rich, Lili Niu, Pengqi Li, Laixin Huang, Yandai Dong, Wei Zhou, Pengfei Zhang, Yizhao Chen, Congzhi Wang, Long Meng, Tony Jun Huang, Hairong Zheng

Faculty Publications

Transfected stem cells and T cells are promising in personalized cell therapy and immunotherapy against various diseases. However, existing transfection techniques face a fundamental trade-off between transfection efficiency and cell viability; achieving both simultaneously remains a substantial challenge. This study presents an acoustothermal transfection method that leverages acoustic and thermal effects on cells to enhance the permeability of both the cell membrane and nuclear envelope to achieve safe, efficient, and high-throughput transfection of primary T cells and stem cells. With this method, two types of plasmids were simultaneously delivered into the nuclei of mesenchymal stem cells (MSCs) with efficiencies of …


Dataset For Article - The Analysis Of Lava Flow Path Using Remote Sensing And Geo-Morphological Techniques: The Case Of Volcano Eruptions In Afar Region Of Ethiopia, Oluwatosin Ayo, Jae Sung Kim Apr 2024

Dataset For Article - The Analysis Of Lava Flow Path Using Remote Sensing And Geo-Morphological Techniques: The Case Of Volcano Eruptions In Afar Region Of Ethiopia, Oluwatosin Ayo, Jae Sung Kim

Michigan Tech Research Data

The lava from volcanic eruptions rapidly moves on the Earth surface and affects both natural and man-made features. The objective of this study is to develop a workflow for determining the optimal ground sample distance of a digital elevation model to delineate the lava flow paths using object-based image analysis and geomorphologic analysis. For the experiment, the satellite images and digital elevation model of Afar region of Ethiopia was used. The satellite images of the affected areas were segmented using large-scale mean shift image segmentation to find the lava objects. The main centerline of the lava object from the 2008 …


Wireless Insights Into Cognitive Wellness: A Paradigm Shift In Alzheimer’S Detection Through Ultrathin Wearable Antennas, Fatma Taher, Moath Alathbah, M. Abdel-Aleim M., Thamer Alghamdi, Mohamed Fathy Abo Sree, Sara Yehia Abdel Fatah Apr 2024

Wireless Insights Into Cognitive Wellness: A Paradigm Shift In Alzheimer’S Detection Through Ultrathin Wearable Antennas, Fatma Taher, Moath Alathbah, M. Abdel-Aleim M., Thamer Alghamdi, Mohamed Fathy Abo Sree, Sara Yehia Abdel Fatah

All Works

The Proposed algorithm, designed to simulate an Alzheimer’s disease (AD) brain model across different stages, presents an invaluable opportunity for further research and in-depth study of the effects of AD. Currently, there is a notable absence of a comprehensive simulated model for the AD brain that allows the exploration of all AD biomarkers within a simulation tool. This represents a crucial advancement in the field, enabling researchers to thoroughly investigate and understand the diverse biomarkers associated with AD without resorting to highly expensive and ionizing radiation techniques. The algorithm’s capability to emulate various stages of AD in a simulated environment …


Nanozyme-Based Sensing Of Dopamine Using Cobalt-Doped Hydroxyapatite Nanocomposite From Waste Bones, Umar Nishan, Nighat Jabeen, Amir Badshah, Nawshad Muhammad, Mohibullah Shah, Irfan Ullah, Saifullah Afridi, Jibran Iqbal, Muhammad Asad, Riaz Ullah, Essam A. Ali, Sarfraz Ahmed, Suvash Chandra Ojha Apr 2024

Nanozyme-Based Sensing Of Dopamine Using Cobalt-Doped Hydroxyapatite Nanocomposite From Waste Bones, Umar Nishan, Nighat Jabeen, Amir Badshah, Nawshad Muhammad, Mohibullah Shah, Irfan Ullah, Saifullah Afridi, Jibran Iqbal, Muhammad Asad, Riaz Ullah, Essam A. Ali, Sarfraz Ahmed, Suvash Chandra Ojha

All Works

Dopamine is one of the most important neurotransmitters and plays a crucial role in various neurological, renal, and cardiovascular systems. However, the abnormal levels of dopamine mainly point to Parkinson’s, Alzheimer’s, cardiovascular diseases, etc. Hydroxyapatite (HAp), owing to its catalytic nature, nanoporous structure, easy synthesis, and biocompatibility, is a promising matrix material. These characteristics make HAp a material of choice for doping metals such as cobalt. The synthesized cobalt-doped hydroxyapatite (Co-HAp) was used as a colorimetric sensing platform for dopamine. The successful synthesis of the platform was confirmed by characterization with FTIR, SEM, EDX, XRD, TGA, etc. The platform demonstrated …


Analysis Of Close Contact Melting, Mohana Durga Gurunadhan Apr 2024

Analysis Of Close Contact Melting, Mohana Durga Gurunadhan

LSU Master's Theses

This report presents a numerical transient analysis of Close Contact Melting (CCM), intended to help in accurate prediction of melt rate and interface configuration, which is to be utilized for a prospective frozen propellant based propulsion system. Three different substrate shapes namely- Flat, Cylindrical and Wedge, are chosen for the study. The domain discretization is based on generation of boundary fitted mesh and the time varying physical domain is transformed to a fixed computational domain, wherein the associated governing equations are solved. Apart from the conventional linear system solvers, an algebraic multigrid based solver is implemented. A non-iterative implicit/explicit melt …


Induced Oxidation Effects On Physical And Mechanical Properties Of Lignite From Tempoku, Hokkaido, Japan For Sustainable Mining Via Subsurface Cultivation And Gasification Method, Akm Badrul Alam, Noritaka Aramaki, Shuji Tamamura, Akio Ueno, Takuma Murakami, Yoshiaki Fujii, Katsuhiko Kaneko Apr 2024

Induced Oxidation Effects On Physical And Mechanical Properties Of Lignite From Tempoku, Hokkaido, Japan For Sustainable Mining Via Subsurface Cultivation And Gasification Method, Akm Badrul Alam, Noritaka Aramaki, Shuji Tamamura, Akio Ueno, Takuma Murakami, Yoshiaki Fujii, Katsuhiko Kaneko

Journal of Sustainable Mining

The lignite resource has been under consideration for the subsurface cultivation and gasification (SCG) method to produce biomethane from lignite in Hokkaido, Japan. The primary phase of the method entails initiating the oxidative transformation of lignite using an H2O2 solution, resulting in the formation of dissolved organic carbon (DOC), a pivotal component. To examine the effects of induced oxidation on lignite's mechanical properties, artificial oxidation tests were conducted to form DOC. While there was a slight decrease in P-wave velocity and density, the uniaxial compression and indirect tensile strengths, as well as stiffness, did not decrease. These …


A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch Apr 2024

A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch

Theses and Dissertations

Robust communication is required to provide a safe airspace for the large numbers of unmanned aerial systems that are coming to the National Airspace System (NAS). This thesis explores methods for providing robust communication to large numbers of vehicles in the NAS. Automatic dependent surveillance-broadcast (ASD-B) is a transmission system that can transmit to and is currently required on all manned aircraft. Unfortunately, ADS-B suffers connectivity problems when supporting large numbers of unmanned aerial systems (UAS). The 5G Cellular protocol can support large numbers of UAS, but connectivity suffers with an increase in distance and interference. Using a 5G cellular …


Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson Apr 2024

Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson

Theses and Dissertations

IEEE 802.11 (WiFi) only has two modes of trust--complete trust or complete untrust. The lack of nuance leaves no room for sensors that a user does not fully trust, but wants to connect to their network, such as a WiFi sensor. Solutions exist, but they require advanced knowledge of network administration. We solve this problem by introducing a new way of modulating data in the latency of the network, called Latency Shift Keying. We use specific characteristics of the WiFi protocol to carefully control the latency of just one device on the network. We build a transmitter, receiver, and modulation …


Modified Coulomb Approach For Squat Silos, Mitchell Cade South Apr 2024

Modified Coulomb Approach For Squat Silos, Mitchell Cade South

Theses and Dissertations

Traditional methods for calculating lateral pressures in silos, such as Janssen's Method and Coulomb's Method, have limitations due to the underlying assumptions of each methodology. This research investigates an approach which adapts Coulomb's Method to account for the cylindrical geometry of silos. The Silo Wedge Method (SWM) distinguishes between two cases based on the aspect ratio (height/diameter) of the silo. Comparative analysis reveals that the SWM accurately matches Coulomb's Method for linear retaining walls when the silo aspect ratio approaches zero. As the aspect ratio increases above 0.25, the SWM exhibits behavior similar to Janssen's Method. This suggests a potential …


Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown Apr 2024

Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown

Theses and Dissertations

This thesis presents a dedicated GPS-denied landing system designed for electric vertical takeoff and landing (eVTOL) aircraft. The system employs active fiducial light pattern localization (AFLPL), which provides highly accurate and reliable navigation during critical landing phases. AFLPL utilizes images of a constellation comprised of modulating infrared lights strategically positioned on the landing site, to determine the aircraft pose through the use of a perspective-n-point (PnP) solver. The AFLPL system underwent thorough development, enhancement, and implementation to address and demonstrate its potential in navigation and its inherent limitations. A proposed method addresses the limitations of AFLPL by using an extended …


Design Of Telemetry And Remote-Control System For Electric Propulsion Testing, Logan Alvesteffer Apr 2024

Design Of Telemetry And Remote-Control System For Electric Propulsion Testing, Logan Alvesteffer

Honors Theses

Ground testing of electric propulsion (EP) devices occurs inside vacuum chambers and is monitored using high-frequency and low-frequency telemetry systems. These systems provide critical operational information about the device’s performance by monitoring values such as voltage, current, gas flow rates, and chamber pressures. Ground facility telemetry systems can operate as integrated control and safety architecture while testing EP devices. EP testing at Western Michigan University (WMU) is located within the Aerospace Laboratory for Plasma Experiments (ALPE). The Cold plasma Experimental Research Station (CEReS) is outfitted with CTI-250F and CTI-10 cryogenic pumps for a combined pumping capacity of 5,200L/s-air. CEReS facilitates …


Energy-Absorbing Helmet For Safer Football, Aidan Laudeman Apr 2024

Energy-Absorbing Helmet For Safer Football, Aidan Laudeman

Honors Theses

Football-related injuries are a common occurrence and are often detrimental to the player’s health. Force impacts frequently occur at the front, back, and sides of a player’s helmet, resulting in head injuries like concussions. The goal of this project is to reduce recurrent head injuries by designing a solution involving the use of energy-absorbing metallic materials that are inserted into a football helmet. These energy-absorbing materials are configured in target zones inside the helmet to reduce the acceleration of the head based on impact locations. The chosen materials are nitinol and spring steel, which display energy-absorbing properties. Various energy-absorbing material …


Electric Ducted Fan Lander, Maggie Waechter Apr 2024

Electric Ducted Fan Lander, Maggie Waechter

Honors Theses

This report, and corresponding project, addresses the fact that there are not many student experiments with controlling real spacecrafts due to the scarceness of the craft, cost, risk, and finite fuel supply. This project demonstrates the possibility of a classroom substitute for students to understand how landers would operate on planetary bodies. In order to achieve flight from the drone, there were two separate designs produced, the electrical and structural system, that were integrated together to form a full prototype. The performance of the electric ducted fans (EDFs) as well as the batteries were tested to ensure that the components …


Hydrogen Fuel Cell Catalyst Test Stand For Single Cell Evaluation, Tyler Johnson Apr 2024

Hydrogen Fuel Cell Catalyst Test Stand For Single Cell Evaluation, Tyler Johnson

Honors Theses

The main objective of this project was to develop at test stand and relevant testing procedures to aid in ongoing research being conducted by Dr. Ghantasala’s team on platinum-alternative catalyst materials used in proton exchange membrane fuel cells (PEMFCs). To do this, various software (Microsoft Excel, Python, and Simscape) were used to create fuel cell simulations of increasing complexity. These simulations served as baselines for PEMFC evaluation in experimental testing, and they were used to create polarization curves, a standard method for evaluating steady state fuel cell performance. A test stand was also created in order to effectively and efficiently …


Development Of Deep Neural Architecture For Continuous Sign Language Video Generation, Natarajan B Apr 2024

Development Of Deep Neural Architecture For Continuous Sign Language Video Generation, Natarajan B

Theses and Dissertations

This dissertation presents a deep neural network based sign language video generation framework for translating the multilingual sentences into sign videos. This thesis addresses the challenges persist with the sign language video generation such as (i) Handling longer sequences of input sentences and new words (ii) Pose estimation with higher accuracy (iii) High quality photo realistic sign gesture video generation (iv) Improving realism in sign video generation. Hence, the thesis focuses four contributions to address the above issues.

The first contribution of this thesis automates the translation of multilingual sentences into sign glosses without manual intervention by incorporating Hybrid Neural …


Techno-Economic Analysis Of Solar Pv Systems Under Various Environmental Conditions, Ramkiran B Apr 2024

Techno-Economic Analysis Of Solar Pv Systems Under Various Environmental Conditions, Ramkiran B

Theses and Dissertations

World Energy Council has predicted that the global electricity demand will peak in 2030. The need for renewable energy has grown rapidly due to the rising energy demand in this ever-growing population. Green house gas emissions are predominantly due to the energy generation and consumption of fossil fuels. On the other hand, fossil fuels supply nearly 74% of India's energy demand, making India one of the world's largest coal consumers.

According to World Resource Institute, India ranks fourth in the world in terms of carbon emissions. Investments in renewable energy sources and energy-saving technologies should be part of a solution …


Soil Stabilization With Gypsum: A Review, Yasaman Abdolvand, Mohammadhossein Sadeghiamirshahidi Apr 2024

Soil Stabilization With Gypsum: A Review, Yasaman Abdolvand, Mohammadhossein Sadeghiamirshahidi

Michigan Tech Publications

The demand for sustainable ground improvement methods is rising as urban development expands into areas with challenging soil conditions. Traditional approaches, mostly reliant on cement and lime, contribute significantly to anthropogenic greenhouse gas emissions. Researchers, therefore, are constantly searching for new environmentally friendly stabilization methods to improve the engineering properties of soils. One alternative material used for this purpose is gypsum in its hydrated and dehydrated (hemihydrate/anhydrate) states. Not only can natural gypsum be used for ground improvement but also industrial waste and by-products (e.g. used or waste plasterboard, phosphogypsum, flue gas desulfurization gypsum, titanium dioxide production gypsum by-product) can …


Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck Apr 2024

Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck

Theses and Dissertations

Current drug-eluting coatings have demonstrated controlled long-term, sustained release but have only tried to mitigate short-term burst release as a negative side effect. For applications like wound healing, there is a need for a drug-eluting coating which is adjustable in both short- and long-term release, independent of each other. We present a tunable dual-phase dual-drug delivery coating composed of drug-loaded polymer microparticles and drug-loaded hydrogel which can control short term and long term release individually in this study. This coating was created using lidocaine and dexamethasone encapsulated in poly(D,L-lactide-co-glycolide) particles combined with lidocaine- and dexamethasone-loaded poly(vinyl alcohol) hydrogel. Hydrogel drug …


Optimal Aoi For Systems With Queueing Delay In Both Forward And Backward Directions, Chih-Chun Wang Apr 2024

Optimal Aoi For Systems With Queueing Delay In Both Forward And Backward Directions, Chih-Chun Wang

Department of Electrical and Computer Engineering Technical Reports

Age-Of-Information (AoI) is a metric that focuses directly on the application-layer objectives, and a canonical AoI minimization problem is the update-through-queues models. Existing results in this direction fall into two categories: The open-loop setting for which the sender is oblivious of the packet departure time, versus the closed-loop setting for which the decision is based on instantaneous Acknowledgment (ACK). Neither setting perfectly reflects modern networked systems, which almost always rely on feedback that experiences some delay. Motivated by this observation, this work subjects the ACK traffic to a second queue so that the closed-loop decision is made based on delayed …