Digital Commons Network^™

Analysis Of Isotopic Effects On Hydrogen Oxidation, Jacob Carter Wilde

Theses and Dissertations

Tritium generation presents a significant hazard during operation of nuclear reactors and necessitates safety precautions in the case of a combustion incident. Accurate kinetic models should inform these safety precautions, however, reliable tritium data do not exist to generate such models. This work focuses on laminar flame speed, which is an important component of kinetic models. Current estimates based on established kinetic theories and experimental measurements of the other isotopes of hydrogen predict tritium to have a flame speed approximately 70% that of standard protium over a broad range of stoichiometries at one atmosphere in air. These estimates are based …

Experimental Study Of The Ultrasonic Extraction Process Of Plant Raw Materials, Azamat Bakir Ogli Usenov, Doston Ishmuxammat Ogli Samandarov, Qobil Akmal Ogli Mukhiddinov, Jasur Esirgapovich Safarov Dcs

Chemical Technology, Control and Management

In-depth scientific research is being conducted around the world aimed at developing the scientific and methodological foundations of energy-saving extractors, processing medicinal plants, increasing the efficiency of modern technologies, processes and equipment for obtaining high-quality pharmaceutical raw materials rich in biologically active substances. Energy-saving extractors, developed in conjunction with the extraction process of medicinal plants, are introduced into the industry using scientifically proven technology. At the global level, special attention is paid to the creation of intelligent designs of innovative extraction plants that operate using ultrasonic waves, allowing the extraction of medicinal components of plants.

Clustering Algorithm Based On Similarity Of Objects, Akhram Khasanovich Nishanov, Alisher Tulkunovich Tursunov, Fayzullo Farhod O'G'Li Ollamberganov

Chemical Technology, Control and Management

The article discusses the problem of drug clustering. Initially, k classes are randomly formed and the resulting training sample is preprocessed, then the similarity between objects of each class is assessed based on the proximity function and the criterion for assessing the contribution of objects to the formation of their own class. It is usually expressed as a percentage and represents the degree of mutual similarity of objects of each class. In the next steps of the algorithm, first one object is taken from the first class and by adding it to all k classes, the contribution of this object …

Optimization Of Bioethanol Production Using An Enzymatic Hydrolysis Process With Green Algae (Chaetomorpha) As The Raw Material, Teuku Maimun, Mirna Rahmah Lubis, Muhammad Aldi Zein, Wahed Febbry Andriansyah Ali

Makara Journal of Technology

Bioethanol is an alternative fuel derived from biological feedstock used to decrease the reliance on fossil fuels because of increasing energy consumption associated with population growth and increased use of oil fuels. Bioethanol production has been widely conducted using several types of algae, but the optimal conditions for the hydrolysis and fermentation processes are not explained in more detail. Therefore, this study focuses on determining the optimal conditions for hydrolysis and fermentation to maximize the bioethanol yield. This study uses optimization based on the hydrolysis time, temperature, and pH to increase the reducing sugar content using high-performance liquid chromatography in …

Scla 521 Ai In Society, Bert Chapman

Libraries Faculty and Staff Presentations

Provides access to information resources on societal impacts of artificial intelligence from multiple libraries databases covering multiple disciplines including government information resources.

A Technical Review On Reservoir Sedimentation And Their Mitigation Strategies, Sadique Khan

AUIQ Technical Engineering Science

Sedimentation in reservoirs is a critical concern of the 21^st century which has affected the sustainability and functionality of water retaining structures. This technical review paper on reservoir sedimentation provides a comprehensive analysis of their causes, mechanisms, and their mitigation/control techniques. The paper starts with sedimentation in the reservoir at a global scale focusing on natural (Soil Erosion) and anthropogenic (man-made) factors such as deforestation, land clearing for agricultural purposes, and urbanization contributing to sedimentation in the reservoir. The origin of sediment is heavily influenced by topographical features, with origins located far-reach, mid-reach and near the reservoir. The sedimentation …

A Novel Perfused Contusion Spinal Cord Injury Model To Assess Rapid Mechanical Properties Changes After Blood Spinal Cord Barrier Breakdown, Laura De Marchi

Theses and Dissertations

Blood-spinal cord barrier (BSCB) disruption exacerbates the tissue damage caused by spinal cord injury (SCI), but the mechanisms and dynamics of how the barrier breakdown affects the mechanical properties of the tissue remain unclear. The perfused bovine ex vivo indentation injury model described here represents a new platform to investigate the short-term effects of altered blood flow and vascular permeability following traumatic spinal cord injury. Our results indicate that injured cords exhibit changes to bulk perfusion, as evidenced by laser speckle contrast imaging, in addition to decreased barrier function shortly after injury. Indentation tests that simultaneously simulate a crush injury …

Fpca-Setcn: A Novel Deep Learning Framework For Remaining Useful Life Prediction, Junde Chen, Yuxin Wen, Xuxue Sun, Adnan Zeb, Mohammad Saleh Meiabadi, Sasan Sattarpanah Karganroudi

Engineering Faculty Articles and Research

The accurate prediction of remaining useful life (RUL) can serve as a reliable foundation for equipment maintenance, thereby effectively reducing the incidence of failure and maintenance costs. In this study, a novel deep learning (DL) framework that incorporates functional principal component analysis (FPCA) and enhanced temporal convolutional network (TCN) is proposed for RUL prediction. Precisely, FPCA is employed to capture the changing patterns in multistream degradation trajectories. Subsequently, the reconstructed signals from FPCA are fed into a convolutional block for extracting deep-level features. An enhanced squeeze-and-excitation (ESE) block is then incorporated into the network for adaptive feature recalibration, enhancing the …

Unveiling The Indoor Performance Of Perovskite/Silicon Tan‑Dem Solar Cells: A Comprehensive Exploration Through Numerically Modelled Energy Band Diagrams, Ziad Khalifa, Sameh O. Abdellatif, Alexander De-Bernardinis, Muath Alkadi, Mostafa Ganoud, Saif Qaid

Chemical Engineering

This paper delves into the indoor performance analysis of Perovskite/Silicon Tandem Solar Cells (PSSTC) through a detailed exploration utilizing numerically modeled energy band diagrams. The primary objective is to uncover the potential of PSSTC for solar energy conversion in indoor settings. Various tandem cell configurations are scrutinized under diverse artificial lighting spectra, with an innovative Li4Ti5O12/ CsPbCl3/MAPbBr3/CH3NH3PbI3/ Si architecture achieving an exceptional maximum power conversion efficiency of 25.25%. This represents a substantial efficiency enhancement of nearly 7% compared to standalone Silicon cells. The study underscores the significance of design optimization in maximizing performance. The energy band diagram analysis reveals a …

Diffuse Interface Modeling Of Non-Isothermal Stokes-Darcy Flow With Immersed Transmissibility Conditions, Hyoung Suk Suh

Faculty Scholarship

The coupling between free and porous medium flows has received significant attention since it plays an important role in a wide range of problems from fluid-soil interactions to biofluid dynamics. However, modeling this coupled process remains a difficult task as it often involves a domain decomposition algorithm in conjunction with a special treatment at the interface. The problem can become more challenging under non-isothermal conditions because it requires the iterative procedure at every time step to simultaneously meet the transient mass continuity, force equilibrium, and energy balance for the entire system. This article presents a diffuse interface framework for modeling …

Damage Of Nickel-Coated Glass/Epoxy Foam-Core Composites Induced By Artificial Lightning Strikes, Van-Tho Hoang, Won-Ho Choi, Juhyeong Lee, Chanyeop Park, Jin-Hwe Kweon, Byeong-Su Kwak, Young-Woo Nam

Mechanical and Aerospace Engineering Faculty Publications

In the field of composite materials, many reports have shown that catastrophic structural damage is caused by lightning strikes. In this study, new design concepts were proposed for the lightning-strike protection of nickel-coated glass/epoxy foam-core composites. Instead of using a neat metal mesh, glass fibers were modified with nickel particles via a plating technique to improve their thermal and electrical conductivities. In addition, a thin Invar plate was inserted at the middle of the structure and a foam core was introduced to reduce damage to the structure. Three models with different materials and stacking sequences were used in this study. …

Voltammetric Determination Of Hydrogen Peroxide At Decorated Palladium Nanoparticles/Poly 1,5- Diaminonaphthalene Modified Carbon-Paste Electrode, Ziad Khalifa, Mohamed Fathi Abo Oura, Magdi Abdelazzem, Ablah Hathoot

Chemical Engineering

In this work, palladium nanoparticles (PdNPs)/p1,5-DAN/ carbon paste electrode (CPE) and p1,5-DAN/CPE sensors have been developed for determination of hydrogen peroxide. Both sensors showed a highly sensitive and selective electrochemical behaviour, which were derived from a large specific area of poly 1,5 DAN and super excellent electroconductibility of PdNPs. PdNPs/p1,5-DAN/CPE exhibited excellent performance over p1,5-DAN/CPE. Thus, it was used for detecting hydrogen peroxide (H2O2) with linear ranges of 0.1 to 250 μM and 0.2 to 300 μM as well as detection limits (S/N= 3) of 1.0 and 5.0 nM for square wave voltammetry (SWV) and cyclic voltammetry (C.V) techniques, respectively. …

Polish Energy Sector’S Dependence On Lignite Mining: The Process Of Transition, Marek Widera, Wojciech Naworyta, Paweł Urbański

Journal of Sustainable Mining

This opinion study is devoted to the role of lignite in the Polish energy sector in recent decades, i.e., after the collapse of communism in 1989. Lignite is the primary source of electricity in Poland, second only to hard coal. More than 25–35% of Polish electricity was generated by lignite-fired power plants in 1990–2022. To meet the needs of the energy industry, 46–70 Mt of lignite was mined annually in that period. Hence, Poland was, and still is, one of the world leaders in lignite production. Despite the ongoing transition of the Polish energy sector, changes occur very slowly due …

A Cylindrical Permeation And Diffusion Model For Bingham Grout In Water-Rich Sand Layers And Its Experimental Research, Wang Xuesong, Cheng Hua, Yao Zhishu, Rong Chuanxin, Xie Bao

Coal Geology & Exploration

Objective The disaster prevention and control for water-rich sand layers pose a major challenge to the safe construction of tunnels and deep foundation pits. Typically, the impermeability and bearing capacity of highly water-rich and weakly cemented sand layers are enhanced through permeation grouting via sleeve valve tubes, with resulting grouting concretions being approximately cylindrical. Methods To explore the cylindrical diffusion mechanism of permeation grouting in sand layers, this study constructed a cylindrical diffusion model of radial tube flow for the permeation grouting of Bingham grout in sand layers while considering the tortuosity effects. Subsequently, this study developed a set of …

Real Time Pii Scanning, John David

Electronic Theses and Dissertations

The increased amount of web applications and internet software solutions utilizing cloud frameworks has contributed to large data sets of system log messages being generated constantly. These messages may contain sensitive data, creating an additional security risk for the systems and contributing to the need for analysis of such large volumes of data in real time. Large commercial data monitoring systems can solve for these analysis requirements, but they can be costly. We present a solution to analyzing web application log data which ingests it, processes it and visualizes sensitive data found within in real time. Our solution utilizes an …

Integrating Authentication Schemes In Augmented And Virtual Reality Classrooms, Naheem Noah

Electronic Theses and Dissertations

Augmented Reality and Virtual Reality (AR/VR) technologies are revolutionizing educational experiences, but their widespread adoption hinges on addressing critical security and usability challenges, particularly in the domain of user authentication. This research presents an investigation into the security landscape of AR/VR and explores a graphical authentication scheme called “Things” that enhances both security and usability in immersive learning environments. Through a systematic evaluation of popular AR/VR devices and applications, potential vulnerabilities and limitations were identified, such as high usage of pin/passwords which are susceptible to shoulder-surfing attacks, lack of multi-factor authentication, and unclear data-sharing practices. A review of existing knowledge-based …

Micropatterning Of Biologically Derived Surfaces With Functional Clay Nanotubes, Nisha Lama

Doctoral Dissertations

In this study, we have generalized an assembly of 50 nm diameter clay nanotubes on larger 20-50 μm diameter biological microfibers such as human hair (protein), cotton (cellulose) and synthetic polyethylene terephthalate- PET. We developed a common set of parameters and nanoclay coating techniques on these naturally different microfibers. We exploited and optimized the electrostatic interaction of the components through strategic adjustments in the solvent pH, employing polycation treatment, as well as selectively modifying the halloysite nanotubes with silanes. For 5 mins, a 5 wt% aqueous dispersion of halloysite nanotubes were applied to get approximately 1-2 μm thick fiber coating …

Optogenetic Control Of Bacterial Dormancy, Yousr Dhaouadi Khattab

Dissertations - ALL

The presence of persister cells makes it difficult to eradicate chronic bacterial infections as these dormant subpopulations arise with exposure to stressors and are capable of surviving antimicrobials that target active cells. Persisters can also revert back to normal growing cells when stressors are removed thus reestablishing the infection. It is therefore important to understand the underlying mechanisms of persister formation, as well as wake-up, and target these systems in order to treat chronic bacterial infections. The formation of persisters, however, remains elusive as there is not yet a clear relationship between the various stages of dormancy. Persister cells can …

High-Throughput Analysis Of Topographical Cues For The Expansion Of Murine Pluripotent Stem Cells, Abigail Anne Conner, Yuan Yao, Sarah W. Chan, Deepak Jain, Suzanne M. Wong, Evelyn K. Yim, Muhammad Rizwan

Michigan Tech Publications

The expansion of pluripotent stem cells (PSCs) in vitro remains a critical barrier to their use in tissue engineering and regenerative medicine. Biochemical methods for PSC expansion are known to produce heterogeneous cell populations with varying states of pluripotency and are cost-intensive, hindering their clinical translation. Engineering biomaterials to physically control PSC fate offers an alternative approach. Surface or substrate topography is a promising design parameter for engineering biomaterials. Topographical cues have been shown to elicit profound effects on stem cell differentiation and proliferation. Previous reports have shown isotropic substrate topographies to be promising in expanding PSCs. However, the optimal …

Metal Organic Frameworks Modified Textiles For The Detoxification Of Chemical Warfare Agent / Simulant, Selva Balasubramanian S

Theses and Dissertations

Chemical Warfare Agents (CWAs) have been listed as lethal weapons of mass destruction due to their extreme toxicity and devastating effects. Malfeasant usage of CWAs involved in the current world praxis poses threat to humankind. Owing to their acute lethal toxicity, the pursuit of favorable approaches for the detoxification/degradation are in continuous progress. In current trends, an imminent development of self-detoxification filters is highly desirable against the CWAs exposure. Exploiting protective materials that can be applicable in day – today life for an instantaneous detoxification will be of prodigious importance.

With this background, a series of Zirconium based UiO-66 and …

Data Communication Over Power-Lines: A Review On Technical, And Applications Challenges, Abdi Abdalla

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a review study on the data communication over power-lines, commonly referred to as power-line carrier, power-line communication (PLC), mains communications, or power-line digital subscriber line (PDSL). This study examines the technical and application advantages and challenges associated with adopting PLC as a preferred alternative technology for wideband or broadband data communication. The broader coverage area of the PLC network gives it a distinct advantage over other communication network technologies. Additionally, implementing a communication system using the existing power-line network is more cost-effective and less time-consuming compared to constructing a new network from scratch. However, the primary challenge …

‘‘Domicilelessness’’ And Livelihoods In Urban Areas: Case Of Maasai In Dar Es Salaam, Tanzania, Ombeni Swai

Tanzania Journal of Engineering and Technology (TJET)

The study aimed at demonstrating Maasai migration into Dar es Salaam urban areas and their challenges in accessing accommodation. Methodologically, the study deployed secondary data analysis following a descriptive research design. Furthermore, this study was conducted through both qualitative and quantitative research approaches. The study was conducted from 2018 to 2022 of which a random sample of 100 (N=100) was targeted. The data was analyzed using the Statistical Package for Social Sciences (SPSS Version 16). Findings: The Maasai means of accommodation are divided into four main categories: completed houses (6%), under-construction sites (39%), halfway constructed and abandoned structures (31%), and …

Exploring The Transformation Of Sustainable Collective Spaces: A Study From Mlalakuwa Informal Settlement, Jacob Lutta

Tanzania Journal of Engineering and Technology (TJET)

A major challenge in collective space transformation is addressing the complexity of informal urbanisation in developing countries. Using a case study approach, this paper examines the concerns related to a particular informal settlement's sustainable collective space transformation. One of the key findings is that the absence of formal rules and regulations in the development of informal settlements in combination with land-grabbing leads to the absence of open spaces that could be used collectively. It is observed that sustainability in urban development is another body of critical thought that integrates several streams of current urban elements and embodies various conceptions of …

Lean Manufacturing Practices In Tanzania: Exploring Awareness, Training And Capital Investment, Francis D. Sinkamba

Tanzania Journal of Engineering and Technology (TJET)

With the growing competition among industries in the world, manufacturing industries are now forced to adopt the Lean Manufacturing philosophy to improve their competitive abilities. The adoption of the philosophy is very low in developing countries such as Tanzania, as is demonstrated with 1% of publications and the lack of knowledge and capital for Lean Manufacturing implementation causes this. Furthermore, the contribution of the sector to the Gross Domestic Product in Tanzania is low and stands at 8.4%. The study wants to bridge the gap in training, capital and awareness of Lean Manufacturing in Tanzania. Survey and purposive sampling techniques …

Evaluation Of Business-Driven Reference Architecture For Big Data Analytics Implementation By Public Sector Organizations In Resource-Constrained Setting: A Case Study Of Uganda, Matendo Didas

Tanzania Journal of Engineering and Technology (TJET)

Big Data Analytics (BDA) is a new area at the nexus of agenda, public sector organizations, and government business. It may satisfy the growing need for trustworthy, cost-effective services in the public sector for better, more informed decision-making processes. BDA has been proposed on the planning schedules of several public sector organizations and the government. Therefore, from the previous work, using Uganda as a case study, specifically the Uganda Bureau of Statistics (UBOS), Ministry of Health (MoH), and Ministry of Education and Sports (MoES), this study aims to evaluate a designed Business-Driven Reference Architecture for Big Data Analytics Implementation (BRABDAI) …

A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard

LSU Doctoral Dissertations

The study of gas hydrates has increased significantly over the last two decades because of their potential application in energy storage, production and transportation, water desalination, refrigeration, gas separation, etc. There is a significant interest in commercially developing natural gas hydrates because the energy content of methane hydrate reservoirs (MHRs) is at least twice that of all conventional fossil fuels combined. Additionally, due to the higher storage capacity of hydrates, it is proposed to sequester CO₂ in the form of CO₂ hydrate, thereby reducing the amount of greenhouse gases. Hence, hydrates offer a dual solution to two of …

Investigation Of Heavy Metal Composition And Associated Health Risks From Selected Groundwater Wells In Temeke, Dar-Es-Salaam, Justin M. Jeremiah

Tanzania Journal of Engineering and Technology (TJET)

Water quality continues to be the challenge to residents in Dar es Salaam due to various anthropogenic activities in the city. This study was conducted to assess groundwater quality by determining concentrations of heavy metals. Both probability and Nonprobability sampling techniques were used to collect samples from 40 groundwater wells in 24 wards of Temeke municipal and analysed using Microwave Plasma Atomic Emission Spectrometer (Agilent 4210 MP-AES) at the Geochemistry Laboratory of the University of Dar es Salaam. Results indicated varying heavy metal concentrations ranging from 0.71 ± 0.08 to 6.64 ± 0.21 mg/l for As, 0.02 ± 0.01 to …

Assessment Of Web Security Vulnerabilities For Common Open Source Virtualization Software, Said Ally

Tanzania Journal of Engineering and Technology (TJET)

Open-source hypervisors have emerged as an integral technology for virtualizing server resources in cloud and data center computing. Hypervisor security efficiency is determined by virtual machine isolation, which is a de facto adoption factor in the selection process, as well as its ability to respond to web attacks. This paper assesses the security performance of Proxmox VE and XenServer for type 1 hypervisors, and Kernel Virtual Machine and Oracle Virtual Box for type 2 hypervisors. Security analysis was conducted using common exposures extracted from vulnerability databases and mapped against the OWASP 2013 and 2017 projects. For clarity, experiments were carried …

B-Spline Impulse Response Functions For Transient Ssi Analysis Of Pile Foundations, Kingsley C. Ozegbe

Theses and Dissertations

The advent and consequential advancements in geotechnical earthquake engineering has made soil-structural analysis (SSI) an important component in the analysis and design of earthquake resistant structures. The filtering effects of pile foundations which reduces the seismic demand on pile-supported superstructure when they are subjected to seismic waves have been investigated and confirmed by several researchers in the last 40 years. To this end, several methods of analyzing the effects of SSI have been developed over the years. From the simplified Winkler model to the more robust finite element method (FEM) and boundary element method (BEM), researchers and structural engineers alike …

Microchannel Slip Flow Characteristics By Time Travel After Photobleaching Velocimetry, Brandon James Sellers

Theses and Dissertations

Interfacial science follows the study of observing behavior between two or more phases of matter when in contact. For example, a liquid solution passes through a microchannel, and the walls interact with the fluid shearing along the surface. The fluid particles develop momentum changes from interfacial phenomena and slip along the wall begins to affect the fluid body. Slip flow is a name for the phenomenon, and with it, modeling velocity for the interfacial behavior demands both resolution and minimal interference. Laser-induced fluorescence photobleaching anemometry (LIFPA) works as a sound method for acquiring data on microchannel flow, but it needed …