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2023

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Articles 2611 - 2640 of 9780

Full-Text Articles in Engineering

Scale Model Experiments Of Toxic Gas Production From The Combustion Of Polymers When Applied With Different Droplet Sizes Of Water Mist, Nicharee Thinnakornsutubutr, Masayuki Mizuno, Kazunori Kuwana Aug 2023

Scale Model Experiments Of Toxic Gas Production From The Combustion Of Polymers When Applied With Different Droplet Sizes Of Water Mist, Nicharee Thinnakornsutubutr, Masayuki Mizuno, Kazunori Kuwana

Progress in Scale Modeling, an International Journal

This research experimentally investigated the combustion of polymeric materials with water mist application in an enclosure, with an emphasis on the production of toxic gases. Two different diameters, ~100 and ~260 μm, were tested. The experimental conditions were determined based on Froude similarity laws for low drop Reynolds number conditions. Droplets and polymers’ physical and chemical properties influence the burning/extinguishing behavior and toxic-gas evolution. In general, larger droplets can extinguish a fire in a shorter time, and toxic gas concentrations in a test chamber decreased more rapidly. However, the large droplets tended to cause the flame expansion phenomenon for thermoplastics …

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Pilots’ Desire To Become Future Space Tourism Pilots: Polynomial Regression Using Response Surface Analysis, Robert A. Goehlich, Ralf Bebenroth Aug 2023

Pilots’ Desire To Become Future Space Tourism Pilots: Polynomial Regression Using Response Surface Analysis, Robert A. Goehlich, Ralf Bebenroth

Publications

In this study, we investigated the impact of pilots’ motivation on their desire to be space tourism pilots or to remain in their current occupation (adherence). We analyzed the feedback obtained from a survey questionnaire on a sample consisting of 106 pilots with flying experience. In particular, we compared the pilots’ intrinsic and extrinsic motivations to investigate two outcomes: the desire to become future space pilots or to remain as air pilots. Applying the self-determination theory, we found that intrinsic motivation mattered more than extrinsic motivation. Furthermore, by applying response surface analysis as our statistical tool, it was revealed that …

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A Multi-Aerial Vehicle Platform For Testing Collaborative Mobility Formation Controllers, Matthew Snellgrove Aug 2023

A Multi-Aerial Vehicle Platform For Testing Collaborative Mobility Formation Controllers, Matthew Snellgrove

LSU Master's Theses

Multi-agent systems have potential applications in a multitude of fields due to their ability to perform complex tasks with a high degree of robustness. Decentralized systems are multi-agent systems where sensing, control, and communication responsibilities are distributed amongst the agents giving this scheme a particularly high potential for robustness, adaptability, and complexity; however, this comes with its own list of challenges. Formation control is a topic in multi-agent systems that aims to have the agents moving as a virtual rigid body through space. In the literature, there have been successful implementation of formation control algorithms on robot agents in both …

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Failure Analysis Of Light Poles On Highway Bridges Exposed To Extreme Winds, Yanlin Chen Aug 2023

Failure Analysis Of Light Poles On Highway Bridges Exposed To Extreme Winds, Yanlin Chen

LSU Master's Theses

Light poles are critical secondary structural components that support the functionality and safety of transportation systems. However, they are tall slender structures vulnerable to wind load. This research attempts to analyze the mechanism of the widespread failure (69 poles failed) of light poles on an elevated highway bridge exposed to Category 4 Hurricane Laura (2020). To understand the mechanism of the failure, a comprehensive analysis is conducted. A nonlinear finite element model is created to simulate the structural responses. Wind pressures are obtained and applied to the FEM to perform nonlinear static and transient analysis. Research results indicate that, when …

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An Object-Based Ground Filtering Of Airborne Lidar Data For Large-Area Dtm Generation, Hunsoo Song, Jinha Jung Aug 2023

An Object-Based Ground Filtering Of Airborne Lidar Data For Large-Area Dtm Generation, Hunsoo Song, Jinha Jung

Purdue University Libraries Open Access Publishing Fund

Digital terrain model (DTM) creation is a modeling process that represents the Earth’s surface. An aptly designed DTM generation method tailored for intended study can significantly streamline ensuing processes and assist in managing errors and uncertainties, particularly in large-area projects. However, existing methods often exhibit inconsistent and inexplicable results, struggle to clearly define what an object is, and often fail to filter large objects due to their locally confined operations. We introduce a new DTM generation method that performs object-based ground filtering, which is particularly beneficial for urban topography. This method defines objects as areas fully enclosed by steep slopes …

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Gravimetric Geoid For Egypt Based On Properly Application Of Helmet's Method Of Condensations With Window Remove-Restore Technique, Atef Makhloof, Hussein A. Abd-Elmotaal, Mostafa Ashry Aug 2023

Gravimetric Geoid For Egypt Based On Properly Application Of Helmet's Method Of Condensations With Window Remove-Restore Technique, Atef Makhloof, Hussein A. Abd-Elmotaal, Mostafa Ashry

Mansoura Engineering Journal

This study uses the window-method for merging the gravity field wavelengths inside the remove-restore technique (RRT) to get the gravimetric geoid for Egypt using Helmert's models of condensation. In this case, the window approach (Abd-Elmotaal and Kühtreiber, 2003) was utilized to avert taking the topographic-condensation masses into account twice inside the data frame. A gravimetric geoid for Egypt has been calculated utilizing Helmert's first and second condensations approach and Airy- Heiskanen model. Within the context of the geoid computation, a thorough comparison between the various Helmert approaches and Airy-Heiskanen has been made. The comparison uses the estimated geoid indicators before …

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Deep Learning Techniques For Efficient Evaluation Of Asphalt Pavement Condition, Kamel Mahdy, Ahmed Zekry, Mohamed Moussa, Ahmed Mohamed, Hassan Mahdy, Mohamed Elhabiby Aug 2023

Deep Learning Techniques For Efficient Evaluation Of Asphalt Pavement Condition, Kamel Mahdy, Ahmed Zekry, Mohamed Moussa, Ahmed Mohamed, Hassan Mahdy, Mohamed Elhabiby

Mansoura Engineering Journal

For the last few decades, researchers have been devising a simple and cost-effective method to evaluate pavement distresses to give decision-makers adequate feedbacks about the pavement condition of a certain road. Fortunately, with the evolution and progression of computer vision tools and techniques, good results had been achieved regarding the detection, classification, and quantification of road distress. In this paper, a new efficient process of road distress analysis using deep learning models is introduced. This new process was tested on a collected road dataset to evaluate the efficiency and speed of this low-cost road maintenance system. Promising results were obtained …

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Skills Matter – Up-Skilling Across Construction Stakeholders For Emerging Roles, Avril Behan, Paul Mccormack, Barry Mcauley Aug 2023

Skills Matter – Up-Skilling Across Construction Stakeholders For Emerging Roles, Avril Behan, Paul Mccormack, Barry Mcauley

Conference Papers

The EU’s Climate Target Plan To 2030 (European Union 2020b) of achieving at least 55% reduction in Green House Gas emissions from 1990 levels, delivering towards a climate-neutral economy by 2050, requires systems-level change in the way we design, construct, and operate our built assets. Funding initiatives, such as co-ordinated by BUILD UP Skills, aim to deliver upskilling to the market but targets set by the European Skills Agenda may not be reached at current achievement levels. This paper presents the results of one completed and the progress of one ongoing Horizon 2020 funded project, BIMcert and ARISE, respectively. Learning …

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Acquiring Commanding Heights Of “Gallium System” Semiconductor Technology, Assisting In Achievement Of The First Breakthrough In Optoelectronic Information Industry, Yun Zhang Aug 2023

Acquiring Commanding Heights Of “Gallium System” Semiconductor Technology, Assisting In Achievement Of The First Breakthrough In Optoelectronic Information Industry, Yun Zhang

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

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Study And Policy Suggestions On International Competitive Advantage Of Manufacturing Industry Among China, United States, Japan, And Germany, Xin Guo, Jingjing Zhang, Kangwei Chi, Jingjing Guo Aug 2023

Study And Policy Suggestions On International Competitive Advantage Of Manufacturing Industry Among China, United States, Japan, And Germany, Xin Guo, Jingjing Zhang, Kangwei Chi, Jingjing Guo

Bulletin of Chinese Academy of Sciences (Chinese Version)

Strengthening the competitive advantage of manufacturing and promoting its high-quality development are the key points to build a modern industrial system. This study uses international market share (MS), revealed comparative advantage (RCA), trade competition index (TCI), and price index (PI) from 2005 to 2020 to analyze the evolution of manufacturing competitive advantage and its main sources in major countries. The main findings are as follows. China's labor-intensive industries maintain a strong international competitive advantage, and the international competitive advantage of some capital and technology-intensive industries is increasing. The capital and technology intensive industries in Germany, Japan, and United States have …

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Paradigm Review Of Data Localization In India And Its Implications For China, Ying Fan Aug 2023

Paradigm Review Of Data Localization In India And Its Implications For China, Ying Fan

Bulletin of Chinese Academy of Sciences (Chinese Version)

Data localization is a focal point of global data governance and its impact on global data governance is no longer confined to a single country. Over the years, India has followed a unique policy framework in terms of cross-border data flows and data localization, and its insistence on data sovereignty reflects its position in the international arena. This study uses the Indian data localization paradigm as a research base to discuss the common phenomenon of disconnect between policy motivations and practical effects of data localization, and as an entry point to introduce the latest Indian research findings in this area. …

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On Digital Productivity Base Of Policies For Cross-Border Data Flows Between Rcep Parties And Its Influences—Taking Digital Integration Index As A Reference, Gui Huang, Ru Tao Aug 2023

On Digital Productivity Base Of Policies For Cross-Border Data Flows Between Rcep Parties And Its Influences—Taking Digital Integration Index As A Reference, Gui Huang, Ru Tao

Bulletin of Chinese Academy of Sciences (Chinese Version)

This study reviews the newest legislation and policies of Regional Comprehensive Economic Partnership (RCEP) participating countries on cross-border data flow, and then categorized them according to the ban on data transfer, local storage of data, permission-based regulation, and standards-based regulation. By referring to the indexes in the ASEAN Digital Integration Index, the subject and object factors of digital productivity in RCEP parities are sorted out, as well as the status quo of digital economy. Through the introduction of data value chain theory, the decisive impact of digital productivity factors on the policy formulation of cross-border data flow is expounded; by …

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Research On Multi-Source Heterogeneous Big Data Fusion Based On Wsr, Aihua Li, Weijia Xu, Yong Shi Aug 2023

Research On Multi-Source Heterogeneous Big Data Fusion Based On Wsr, Aihua Li, Weijia Xu, Yong Shi

Bulletin of Chinese Academy of Sciences (Chinese Version)

In the era of multi-source heterogeneous big data, big data presents new features such as cross, diversity and variability. The applications of big data in a wider range of fields have new requirements for data fusion. Under this background, the connotation of data fusion is enriched and expanded. The generalized data fusion includes the fusion of data resources, the fusion of model methods, and the fusion of decision-makers' knowledge and experience. This study analyzes the characteristics of multi-source heterogeneous data fusion at three different fusion levels: data level, information level and decision level, and discusses challenges for data fusion in …

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Threads, Buckets, And Impact: A Framework For Tool Accelerated Machine Learning Courses, Jonathan Adam Niemirowski Aug 2023

Threads, Buckets, And Impact: A Framework For Tool Accelerated Machine Learning Courses, Jonathan Adam Niemirowski

Doctoral Dissertations

Artificial intelligence and machine learning (ML) have exploded in use, accessibility, and awareness in the past few years, particularly with the release of ChatGPT in late 2022. Advances in end-user ML tools are accelerating the development of ML applications, lowering the technical barrier of entry for users outside of the computer science (CS) community. Access to ML education within STEM is mostly limited to upper-level computer science courses that have deep pre-requisite requirements or to introductory workshops that yield limited ML skills. Despite the critical need for ML education, there is a lack of guidance in instructional design for applied …

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Skyqube V2, Robert J. Twiggs Aug 2023

Skyqube V2, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "SkyQube V2" from August 19, 2023.

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Engineering Multifunctional Adhesive Hydrogel Patches For Biomedical Applications, Aishik Chakraborty, Shana Alexander, Wei Luo, Narisse Al-Salam, Mia Van Oirschot, Sudhir H. Ranganath, Subrata Chakrabarti, Arghya Paul Aug 2023

Engineering Multifunctional Adhesive Hydrogel Patches For Biomedical Applications, Aishik Chakraborty, Shana Alexander, Wei Luo, Narisse Al-Salam, Mia Van Oirschot, Sudhir H. Ranganath, Subrata Chakrabarti, Arghya Paul

Chemical and Biochemical Engineering Publications

Traditional patches, such as sticking plaster or acrylic adhesives used for over a hundred years, lack functionality. To address this issue of poor functionality, adhesive hydrogel patches have emerged as an efficient bioactive multifunctional alternative. Hydrogels are three-dimensional, water-swellable, and polymeric materials closely resembling the native tissue architecture. The physicochemical properties of hydrogels can be modified easily, allowing them to be suitable for various biomedical applications. Moreover, adhesive properties can be imparted to hydrogels through physicochemical manipulations, making them ideal candidates for supplementing or replacing traditional sticking plaster. As a result, sticky hydrogel patches are widely used for transdermal drug …

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Multi-Agent Deep Reinforcement Learning For Radiation Localization, Benjamin Scott Totten Aug 2023

Multi-Agent Deep Reinforcement Learning For Radiation Localization, Benjamin Scott Totten

Dissertations and Theses

For the safety of both equipment and human life, it is important to identify the location of orphaned radioactive material as quickly and accurately as possible. There are many factors that make radiation localization a challenging task, such as low gamma radiation signal strength and the need to search in unknown environments without prior information. The inverse-square relationship between the intensity of radiation and the source location, the probabilistic nature of nuclear decay and gamma ray detection, and the pervasive presence of naturally occurring environmental radiation complicates localization tasks. The presence of obstructions in complex environments can further attenuate the …

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Extreme Cooling Via Sweeping Gas Membrane Distillation, David M. Warsinger Aug 2023

Extreme Cooling Via Sweeping Gas Membrane Distillation, David M. Warsinger

School of Mechanical Engineering Faculty Publications

Thermal desalination processes like membrane distillation (MD) aim to have rapid evaporation rates to provide large quantities of fresh water. These processes, which resemble counterflow-heat exchangers with membranes in the middle, conventionally seek to maximize vapor mass transfer while minimizing all other modes of heat transfer as “thermal losses.” However, we can reverse this fundamental design need to make an exceptionally high throughput heat dissipation device. By using thin thermally conductive membranes and extremely rapid air flow rates, membrane heat exchangers inspired by MD can dissipate heat several times faster than conventional air-cooled heat exchangers. We demonstrate this new approach …

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Don't Fear The Artificial Intelligence: A Systematic Review Of Machine Learning For Prostate Cancer Detection In Pathology, Aaryn Frewing, Alexander B. Gibson, Richard Robertson, Paul Urie, Dennis Della Corte Aug 2023

Don't Fear The Artificial Intelligence: A Systematic Review Of Machine Learning For Prostate Cancer Detection In Pathology, Aaryn Frewing, Alexander B. Gibson, Richard Robertson, Paul Urie, Dennis Della Corte

Faculty Publications

The adoption of whole slide image (WSI) scanners in clinical practice was accelerated by US Food and Drug Administration approval in 2017, which allowed primary pathologic diagnoses to be made on scanned images. Images in the digital domain allow the application of pathology artificial intelligence (AI), including clinical decision support with algorithms performing specific diagnoses.1,2 These algorithms, if trained properly, could go beyond the ability of human observation to detect and quantify features that are not recognizable by human perception.1,3,4

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A New Planning Proposal For Achieving Residents’ Thermal Comfort In Hot Arid Climate- Based On Simulation Model, Mohamed A. Eid, Randa M. A. Mahmoud, Amr Sayed Hassan Abdallah Aug 2023

A New Planning Proposal For Achieving Residents’ Thermal Comfort In Hot Arid Climate- Based On Simulation Model, Mohamed A. Eid, Randa M. A. Mahmoud, Amr Sayed Hassan Abdallah

Mansoura Engineering Journal

This paper aims to propose a new planning approach that achieves residents' thermal comfort inside the courtyards of residential complexes based on the improvement of the urban canyon ratio in the current residential complex in New Assiut city as a base case, including their role in boosting social interaction and improving residents’ Outdoor thermal comfort (OTC) and courtyard air quality. This new planning proposal is based on the planning of old Arab cities that encourages liveability, walkability, social interaction, and sustainability. Then, improvement of urban canyon ratios for the new planning proposal was simulated and optimized using ENVI-met 5. Eight …

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A Nonstandard Finite Difference Numerical Solution For The Equal-Width Wave Equation, H. A. Elagamy, Z. F. Abushaeer, Galal I. El-Baghdady Aug 2023

A Nonstandard Finite Difference Numerical Solution For The Equal-Width Wave Equation, H. A. Elagamy, Z. F. Abushaeer, Galal I. El-Baghdady

Mansoura Engineering Journal

This study aims to develop an unconditionally stable numerical scheme for the equalwidth wave equation. An unconventional finite difference discretization is employed to accomplish this. The John von Neumann methodology is used to examine the stability of the suggested method, and the suggested scheme's precision is established. Numerical results with comparisons are shown to demonstrate the viability of the suggested approach for the equal-width wave equation.

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Integrated Water Quality Assessment In Damietta Branch Intakes At Dakahlia Governorate, Egypt, M. Elbagoury, H. Omara, Bakenaz A. Zeidan Aug 2023

Integrated Water Quality Assessment In Damietta Branch Intakes At Dakahlia Governorate, Egypt, M. Elbagoury, H. Omara, Bakenaz A. Zeidan

Mansoura Engineering Journal

The water quality of the Damietta branch evaluated and assessed using the water quality index (WQI), including twenty-one physical, chemical, and biological parameters (Temperature, Turbidity, Chlorine, Electrical Conductivity, Total Dissolved Solids, pH, Chloride, Total Alkalinity, Total Hardness, Dissolved Oxygen, Chemical Oxygen Demand, Biological Oxygen Demand, Nitrogen, Sulfate, Calcium, Total phosphorus, Sodium, Potassium, Nitrate, Magnesium, and Total Coliform) measured at eleven different drinking water intake stations in Dakahlia governorate along the Damietta branch of the Nile river for four successive years from 2018 to 2021. The scale for evaluating the water quality of the Damietta branch of the Nile River is …

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Exact/Partial Cipher-Text Retrieval On The Encrypted Cloud Database Using Sckha Algorithm, Samia Souror, Mohammed Badawy, Nawal El-Fishawy Aug 2023

Exact/Partial Cipher-Text Retrieval On The Encrypted Cloud Database Using Sckha Algorithm, Samia Souror, Mohammed Badawy, Nawal El-Fishawy

Mansoura Engineering Journal

Searchable encryption techniques are intelligent tools that attempt to solve the challenge of querying stored data on untrusted cloud servers while preserving data confidentiality. This paper proposes simple, powerful, and practical Searchable Symmetric Encryption (SSE) scheme which capable of executing SQL (Structural Query Language) queries over encrypted cloud databases. Our scheme improves the efficiency of the search over encrypted data by using the SCKHA (Symmetric Cipher based on Key Hashing Algorithm) algorithm instead of using the bloom filter technique which causes the problem of the false positives. We built a complicated index structure for the encrypted data by combining the …

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Preparing For V2x Deployment: Evaluating Current Anonymity Implementations, And Developing A Framework For Gauging Roadside Unit Networkability, Daniel Arnaudov Sharp Aug 2023

Preparing For V2x Deployment: Evaluating Current Anonymity Implementations, And Developing A Framework For Gauging Roadside Unit Networkability, Daniel Arnaudov Sharp

Theses and Dissertations

In this thesis we answer two questions relating to the impending deployment of V2X. We answer, "What is the state of current privacy measures implemented to prevent tracking and promote anonymity?" We answer this by showing that tracking methods used to circumvent changing IDs are possible. We also show through conservative calculations that this problem will not go away on its own and requires direct effort. We also answer, "Is the available production V2X hardware ready for scalable deployment?" To do this we develop a framework for evaluating RSUs and many of their core functions related to deployment, scalability, and …

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Designed For Better Control: Using Kinematic And Dynamic Metrics To Optimize Robot Manipulator Design, John R. Morrell Aug 2023

Designed For Better Control: Using Kinematic And Dynamic Metrics To Optimize Robot Manipulator Design, John R. Morrell

Theses and Dissertations

In the field of control theory, optimal performance is generally defined as the best possible controlled performance given a static, unchangeable plant system. However, principled design of the underlying system can make designing effective controllers easier and dramatically improve the final control performance beyond what any finely tuned controller could achieve alone. This work develops performance metrics for serial robot arms which help guide the design and optimization of the structure of the arm to achieve greater final performance. First, a kinematic (motion-based) metric called the Actuator Independence Metric (AIM) measures the uniqueness of the movement capabilities of the different …

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Explainable Ai For Tool Wear Prediction In Turning, Saleh Valizadeh Sotubadi, Rui Liu, Vinh Nguyen Aug 2023

Explainable Ai For Tool Wear Prediction In Turning, Saleh Valizadeh Sotubadi, Rui Liu, Vinh Nguyen

Michigan Tech Publications

This research aims develop an Explainable Artificial Intelligence (XAI) framework to facilitate human-understandable solutions for tool wear prediction during turning. A random forest algorithm was used as the supervised Machine Learning (ML) classifier for training and binary classification using acceleration, acoustics, temperature, and spindle speed during the orthogonal tube turning process as input features. The ML classifier was used to predict the condition of the tool after the cutting process, which was determined in a binary class form indicating if the cutting tool was available or failed. After the training process, the Shapley criterion was used to explain the predictions …

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Watch: A Distributed Clock Time Offset Estimation Tool On The Platform For Open Wireless Data-Driven Experimental Research, Cassie Jeng Aug 2023

Watch: A Distributed Clock Time Offset Estimation Tool On The Platform For Open Wireless Data-Driven Experimental Research, Cassie Jeng

McKelvey School of Engineering Graduate Student Theses & Dissertations

The synchronization of the clocks used at different devices across space is of critical importance in wireless communications networks. Each device’s local clock differs slightly, affecting the times at which packets are transmitted from different nodes in the network. This thesis provides experimentation and software development on POWDER, the Platform for Open, Wireless Data-driven Experimental Research, an open wireless testbed across the University of Utah campus. We build upon Shout, a suite of Python scripts that allow devices to iteratively transmit and receive with each other and save the collected data. We introduce WATCH, an experimental method to estimate clock …

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Modeling Of Heat And Mass Transfer In Flat Heat Pipes, Salar Saadatian Aug 2023

Modeling Of Heat And Mass Transfer In Flat Heat Pipes, Salar Saadatian

LSU Doctoral Dissertations

Phase-change phenomenon is ubiquitous in nature and widely utilized in thermal management of computer chips. Flat heat pipes have been extensively used in thermal management of microelectronic devices. However, existing research mainly concentrates on developing numerical models and lacks a systematic analytical approach to elucidate the working mechanism of flat heat pipes. We consider a horizontal flat heat pipe with an idealized porous wick. The pores in the wick are straight circular capillaries running along and across the wick and are filled with a liquid. The rest of the pipe is filled with its vapor. The mass evaporative rate at …

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Mechanochemical Esterification Of Cellulose Nanofibers Lyophilized From Eutectic Water–Tert-Butanol Mixtures, Miran Mavlan, Taehoo Chang, Rudan Feng, Jake R. Wilkinson, Robert J. Nicholas, Nosa B. Idahagbon, Jeffrey Youngblood, Alexander Wei Aug 2023

Mechanochemical Esterification Of Cellulose Nanofibers Lyophilized From Eutectic Water–Tert-Butanol Mixtures, Miran Mavlan, Taehoo Chang, Rudan Feng, Jake R. Wilkinson, Robert J. Nicholas, Nosa B. Idahagbon, Jeffrey Youngblood, Alexander Wei

Department of Chemistry Faculty Publications

Freeze-dried CNFs can be modified by mechanochemical (MC) processes with minimal use of auxiliary solvents, however aggregation of nanofibers during lyophilization compromises their granularity and reaction efficiency. Adding 10 wt% tert-butanol (TBA) to aqueous slurries of wood-derived CNF creates a eutectic mixture that reduces hornification during lyophilization, resulting in well-formed aerogels with minimal shrinkage in volume. CNFs lyophilized from mixtures containing at least 10 wt% TBA exhibit an order of magnitude increase in specific surface area relative to CNFs freeze-dried from water alone. The amount of TBA and input energy needed for lyophilization can be reduced considerably by dewatering …

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On The Design And Power Output Response Of Hydraulic Wind Turbines, Helber Antonio Esquivel-Puentes, Andrea Vacca, Venkatesh Pulletikurthi, Ali Doosttalab, Jose Garcia-Bravo, David M. Warsinger, Leonardo P. Chamorro, Luciano Castillo Aug 2023

On The Design And Power Output Response Of Hydraulic Wind Turbines, Helber Antonio Esquivel-Puentes, Andrea Vacca, Venkatesh Pulletikurthi, Ali Doosttalab, Jose Garcia-Bravo, David M. Warsinger, Leonardo P. Chamorro, Luciano Castillo

School of Mechanical Engineering Faculty Publications

Standard horizontal axis wind turbines typically use gearboxes for large-scale applications and direct coupling for small-scale designs to connect the rotor to the generator. However, gearboxes pose challenges due to their weight, cost, and exposure to dynamic loads and vibrations within the nacelle. A promising alternative is replacing mechanical transmission with a hydrostatic counterpart, offering advantages such as reduced nacelle mass, generator placement at the tower base, and elimination of the gearbox. It can potentially lead to cost savings of up to 20% in the levelized cost of electricity for offshore wind turbines. This study compares regulated hydrostatic transmission with …

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