Engineering Commons^™

Performance Of Calcium Chloride- Ammonia Adsorption Refrigeration System, Michael John

Tanzania Journal of Engineering and Technology (TJET)

An experimental study on the performance of calcium chloride-ammonia adsorption system is described. A single bed water cooled condenser adsorption refrigerator prototype, which utilises calcium chloride-ammonia pair has been developed and tested in the laboratory. Experiments have been conducted for desorption temperatures of 100 °C with desorption time varying from 1 to 4 hours. An electric tape heater and a timer were used to perform the experiments. The adsorption temperature profile, adsorption rate and prototype performance have been analysed and discussed. The tested heating and desorption temperature of 100 °C and heating and desorption time of 1 to 4 hours …

Prediction Of Uniaxial Compressive Strength Of Granite Rock Samples Of Lugoba Quarry Using Rebound Hammer Test, Moses Kongola, Karim Baruti

Tanzania Journal of Engineering and Technology (TJET)

Rebound hammer test is widely used as an indirect measure of uniaxial compressive strength for engineering materials such as concrete, soil, and rock in both civil and mining engineering works. In quarries, uniaxial compressive strength is a crucial parameter in the analysis of geotechnical problems involving rock stability and rock blasting design. This study aims at establishing the empirical models of uniaxial compressive strength fits on rebound hammer number that can be used to predict uniaxial compressive strength of granitic rock at Lugoba Quarry. Data for direct uniaxial compressive strength were obtained from uniaxial compressive strength test carried out on …

Socio-Technical Perspective For Electronic Tax Information System In Tanzania, Lucas Ngowi, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Socio-technical systems theory has rarely been used by system architects in setting up computing systems. However, the role of socio-technical concepts in computing, which is becoming social in nature, has made the concepts more relevant and commercial. Tax information systems are examples of such systems because they are influenced by external variables such as the political environment, technological trends, and social environment, introducing complexity in their deployment and determining the type of e-services and their delivery to a diverse group of people. It was observed that in Tanzania there is resistance, reluctance and minimal use of electronic tax system because …

Considering Social Impact When Engineering For Global Development, Hans Jorgen Ottosson

Theses and Dissertations

Every manufactured product has an environmental impact, a social impact, and an economic impact. As engineers, we should do our best to understand how our design decisions influence these impacts (the three pillars of sustainability), and at the same time make decisions that collectively lead to maximum positive impacts, or minimum negative impacts on the economy, environment, and society. Many times, engineers show interest and want to design for all three pillars of sustainability but are often constrained to focus on the environmental and economic aspects, leaving out social sustainability due to lack of understanding and resources. In practice, this …

Production Of Pure Vanadium: Industry Review And Feasibility Study Of Electron Beam Melt Refining Of V–Al Alloys, Devin Rappleye, Rob Haun

Faculty Publications

The vanadium industry has experienced significant change over the last two decades with the emergence of vanadium redox flow batteries for grid-level energy storage, the growing demand for high-strength steel, and the selection of vanadium as a critical material in multiple countries. This review presents the status of the vanadium industry examining production processes and detailing facilities. The available information for each producer is presented including vanadium products and capacity. The production of pure vanadium is identified as a potential vulnerability for some nations where vanadium metal is needed in small, yet strategic, applications and globally only two producers of …

Single-Particle Characterization Of Sars-Cov-2 Isoelectric Point And Comparison To Variants Of Interest, Oluwatoyin Areo, Pratik U. Joshi, Mark Obrenovich, Moncef Tayahi, Caryn L. Heldt

Michigan Tech Publications, Part 1

SARS-CoV-2, the cause of COVID-19, is a new, highly pathogenic coronavirus, which is the third coronavirus to emerge in the past 2 decades and the first to become a global pandemic. The virus has demonstrated itself to be extremely transmissible and deadly. Recent data suggest that a targeted approach is key to mitigating infectivity. Due to the proliferation of cataloged protein and nucleic acid sequences in databases, the function of the nucleic acid, and genetic encoded proteins, we make predictions by simply aligning sequences and exploring their homology. Thus, similar amino acid sequences in a protein usually confer similar biochemical …

Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed

LSU Master's Theses

Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …

Water Regulation For Enhancing Soil Quality Using Cactus Mucilage: A Theoretical And Experimental Analysis, Khuloud Alrashdi

USF Tampa Graduate Theses and Dissertations

As water is one of the primary sources of life, it is essential in an endless number of systems and processes to be utilized efficiently in nature and in practical applications. One of these applications includes farming, which depletes a lot of water as the water irrigation systems cover large soil areas. While water is a critical factor in growing crops, a question here stands, can the irrigation process be transformed? This is the overarching goal of my work since it is centered on studying if cactus mucilage, a natural substance, is capable of improving water absorption processes on crops …

Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki

Dissertations and Theses

Cyanobacteria exist throughout the world and are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change, increased nutrient loading, and other anthropogenic impacts on waterbodies are expected to increase the prevalence of cyanobacteria. It is vital that we protect our drinking water supplies and natural water resources. Modeling the production and movement of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. Cyanotoxins are diverse and the conditions under which they are formed …

Riyadh Neighborhood Residents’ Use And Satisfaction With Urban Green Spaces, Tahar Ledraa, Majed Hallawani, Awad Al-Qahtani

Emirates Journal for Engineering Research

Neighborhood urban green spaces are indispensable elements for residents’ rest and recreation. They are also of paramount importance to enhance quality of life within neighborhoods. However, these urban green spaces did not receive much research interest, particularly in cities of the developing world. Larger city parks seem to have been the focus of studies. The present study is undertaken under the contention that dissatisfaction with a service is the difference between what is expected from that service and what is really experienced out of it. The gap between expectancy and what is experienced in reality would lead to how satisfied …

Cfd Simulation Of Supercritical Flow In Narrow Channels Including Sediment Bypass Tunnels, Subhojit Kadia, Elena Pummer, Nils RüTher

International Junior Researcher and Engineer Workshop on Hydraulic Structures

Secondary currents, turbulence characteristics and bed shear stress distribution are the crucial parameters for specifying sediment transport. Hence, to understand the sediment transport in sediment bypass tunnels (SBTs), we performed computational fluid dynamics (CFD) simulation of supercritical flow in a narrow straight channel. The results of the steady state simulation (Froude number ≈ 1.8) were compared with experimental results. The commonly used two-equations linear eddy-viscosity models are limited to isotropic turbulence closure and hence could not replicate the desired secondary currents. Therefore, the LRR Reynolds Stress Model was used, and predicted the flow features and the secondary currents (three kinds …

Discharge Capacity Of A Piano Key Weir With Curvilinear Keys, R. K. Mishra, Z. Ahmad

International Junior Researcher and Engineer Workshop on Hydraulic Structures

The Piano Key Weir (PKW) has emerged as a cost effective and viable solution for dam rehabilitation and new projects with high level of space constraints. The geometrical dimensions of PKW are main factors affecting their discharging capacity. Since, it is a relatively new type of weir that has only been developed in recent years, the description of the effect of its geometrical parameters is still immature. The geometric designs of these weirs presented in the literatures incorporate only linear floor slope of the keys. For better understanding of the influence of curvilinear shapes of outlet key slopes on discharge …

Western Kentucky University Stormwater Utility Survey 2021, Warren Campbell, Jerry Bradshaw

SEAS Faculty Publications

No abstract provided.

Scheduling Allocation And Inventory Replenishment Problems Under Uncertainty: Applications In Managing Electric Vehicle And Drone Battery Swap Stations, Amin Asadi

Graduate Theses and Dissertations

In this dissertation, motivated by electric vehicle (EV) and drone application growth, we propose novel optimization problems and solution techniques for managing the operations at EV and drone battery swap stations. In Chapter 2, we introduce a novel class of stochastic scheduling allocation and inventory replenishment problems (SAIRP), which determines the recharging, discharging, and replacement decisions at a swap station over time to maximize the expected total profit. We use Markov Decision Process (MDP) to model SAIRPs facing uncertain demands, varying costs, and battery degradation. Considering battery degradation is crucial as it relaxes the assumption that charging/discharging batteries do not …

Response-To-Failure Analysis Of Global Food System Initiatives: A Resilience Perspective, Prince Agyemang, Ebenezer Miezah Kwofie

Biological and Agricultural Engineering Faculty Publications and Presentations

International food system initiatives have led the efforts to combat the threats to global food security resulting from the failure of the current food systems. This study set out to investigate and assess the contributions of global food system initiatives in tackling the food system challenges. In assessing the food system initiatives, we develop a three-step methodology for Food System Initiative (FSI) selection and then conduct a qualitative evaluation using relevant indicators based on food system failure narratives. Furthermore, the authors synthesize present literature in the context of the extent to which coronavirus disease 2019 (COVID-19) pandemic has compounded food …

Optimization Of Vaccine Supply Chains In Low- And Middle-Income Countries Utilizing Drones, Maximilian Kolter

Graduate Theses and Dissertations

Despite tremendous efforts from governments and humanitarian organizations, millions of children in low- and low-middle-income countries (LICs and LMICs) are still excluded from the benefits of immunization. The vaccine distribution in LICs and LMICs is challenging for several reasons, such as limited cold chain capacities, vaccine wastage, uncertain demand, and lack of access to immunization services. A promising avenue to address these issues is the utilization of drones for vaccine delivery. Drones can fly at high speed on direct paths and could enable on-demand deliveries to mitigate limited storage capacities. Further, their independence of road networks could allow them reaching …

Novel Eco-Friendly, Recycled Composites For Improved Ca Road Surfaces, Daniel Whisler, Rafael Gomez Consarnau, Ryan Coy

Mineta Transportation Institute

The continued use of structural plastics in consumer products, industry, and transportation represents a potential source for durable, long lasting, and recyclable roadways. Costs to dispose of reinforced plastics can be similar to procuring new asphalt with mechanical performance exceeding that of the traditional road surface.

This project examines improved material development times by leveraging advanced computational material models based on validated experimental data. By testing traditional asphalt and select carbon and glass reinforced composites, both new and recycled, it is possible to develop a finite element simulation that can predict the material characteristics under a number of loads virtually, …

Developing A Lab-Scale Fluidized Bed Dryer System To Enhance Rough Rice Drying Process, Kaushik Luthra

Graduate Theses and Dissertations

For more than half of the world's population, rice (Oryza sativa L.) is a staple meal. However, rice growers encounter difficulties supplying this demand, particularly in developing nations, where rice is susceptible to spoilage if the moisture content is not lowered to a safe level soon after harvest. As a result, traditional drying methods, such as sun drying and natural air drying, are commonly used by rice growers, particularly in underdeveloped nations. However, these procedures are time-consuming and can lead to rice spoilage. On the other hand, fluidized bed drying is a well-established technology that might give rice growers a …

Scholarly Communication On Web 3.0: An Analysis Based On Web Of Science, Arunkumar V R

Library Philosophy and Practice (e-journal)

For investigating the structure and process of academic communication, bibliometrics provides an excellent set of methodologies and measures. Web 3.0 is a concept that incorporates artificial intelligence and other advanced technologies and brings forth new opportunities and challenges to information scientists. The present study provides an evaluation of the scientific productivity related to Web 3.0 technologies in Web of Science (WoS) during the period of 2007 to 2020. The country-wise distribution of the literature revealed that the majorities (22.330%) of the documents were published from the USA, followed by Spain, and scholarly output of Web 3.0 literature received a total …

Development And Validation Of The Itf Scale: An Investigation Of Airline Passengers’ Intention To Fly During A Global Disruption, Guangda Liang

Theses and Dissertations

The purpose of the current study was to develop and validate the ITF scale that measured airline passengers’ intention to fly during a global disruption. Based on the review of the literature, the researcher identified several dimensions, and each dimension was measured by question items. The target population of the current study was airline passengers in the United States who were at least 18 years old. A sample was collected using the convenience sampling. The questionnaire was distributed online. The ITF scale was validated using data collected from the online questionnaire. A factor analysis was performed. The results of the …

Economic Assessment Of Factors Affecting The Decision Of Households To Engage In Non-Farm Activities, Sh.A. Muratov

Irrigation and Melioration

In this study, non-farm activities and their importance were studied, and it is analysed the influence of push and pull factors on the decision of family heads to engage in non-farm activities by Probit model regression. Furthermore, it is determined their elastic coefficients. The analysed data are collected by conducting an online survey from 134 respondents. The results are showed that the decision of family heads to engage in non-farm activities was greatly influenced by their gender, education, and number of family members, electricity supply, transport services, and size of their land. Namely, the decision of the head of the …

Identifying The Determinants And Extent Of Crop Diversification At Farm Level: A Case Study Of Uzbekistan, A.Э. Primov, M.H. Saidov, I. B. Rustamova, A.A. Abduvasikov

Irrigation and Melioration

Since independence, the government of Uzbekistan has implemented the number of agricultural policies such as making some crucial structural reforms at the farms, comprising different institutions and enhancing diversification of agricultural production in order to stabilize the agricultural sector of the country. Therefore, crop diversity has an important role in sustainable agriculture. We calculated the diversification index based on the Simpson Diversity Index method while ordinary least square (OLS) regression analysis was employed to assess the association of crop diversification on farm income using cross-sectional data from 381 farmers of Uzbekistan. The study revealed the mean computed Simpson Index values …

Analysis On The Deployment Of Mining Research Supported By The Grant Program Of Deep Resources Exploration And Mining, Fan Jun, Zhang Jialin, Qin Yuan, Wang Hao, Gao Yanan, Pei Yongzhi

Coal Geology & Exploration

The Deep Resources Exploration and Mining(DREAM) grant program, within the framework of The National Key Research and Development Program grants, is a pillar to implement China’s science and technology strategy in the area of deep resources exploitation. To tackle the insufficient of theories and technologies for the 1000-meter-deep mining, a section of mining, covering the research of basic theories, general technologies and application demonstration, was arranged in the layout of DREAM under the principle of "whole chain design, integrated implementation". In the aspect of basic research, DREAM mainly focused on the deep rock mechanics and mining theory, such as the …

Issue 7: Contributors, David Hartshorn, Martin Jarrold

Online Journal of Space Communication

List of Issue 7 Contributors.

Future Solutions: Universal Access, David Hartshorn

Online Journal of Space Communication

Today, the nations of the world have an immediate opportunity to advance essential telecommunication policy objectives through harmonisation of regulations governing the use of fixed satellite-based network solutions.

Regulatory Reform: Strengthening Access To Information & Communications Technologies: Guidelines To Facilitate Policy & Regulation For Satellite Services, Global Vsat Forum

Online Journal of Space Communication

This document was prepared by GVF, an association of organisations engaged in the delivery of advanced broadband and narrowband satellite services to consumers, and commercial and government enterprises worldwide.

Regulatory Reform: Asia's Great Step Forward, David Hartshorn

Online Journal of Space Communication

This paper was presented at Connect-World Asia Pacific, June 2002.

Forget about a great leap forward. All that's needed to facilitate communications in Asia are a few small steps. Indeed, today all nations of the world have an immediate opportunity to advance essential telecommunication policy objectives through harmonisation of regulations governing the use of telecommunications solutions.

Regulatory Reform: Wanted: A Bridge For Africa's Digital Divide Apply: Pretty Much Anywhere In Africa Quote Reference: Vsat, Martin Jarrold

Online Journal of Space Communication

For Africa, and for the economy of the whole planet, those hundreds of millions of people across the continent who are currently denied reasonable access to even simple voice service represent a vast untapped pool of creativity. This very large and potentially very powerful economic dynamo demands access to more than the simplest tools of communication, and requires the means to unleash the potential productivity of its own knowledge-base into an increasingly connected world. The International Telecommunications Union acknowledges this, as does its sister organisation, the United Nations. The Global VSAT Forum enjoins you to acknowledge it too.

Overview: A+B+C = Vsat, Martin Jarrold

Online Journal of Space Communication

The benefits of VSAT systems and services are being realised in all spheres across the globe, both private and public. Banks, government departments, schools, hospitals, home offices, small enterprises, multi-national corporates, and rural telephony… all sectors are seizing upon the opportunity to get connected through satellite communications.

Overview: Satellite Communication In Ghana - Challenges And Prospects, Kwasi Boateng

Online Journal of Space Communication

Busy Internet is a Ghanaian ISP that uses satellite connectivity to bring Internet to West Africans. The operations of this ISP illustrate the reliability, versatility and efficiency of, VSAT, (Very Small Aperture Terminal) networks in delivering fast broadband Internet services.