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Articles 31 - 60 of 126

Full-Text Articles in Engineering Science and Materials

Production Of Biofertilizer From Fruit And Garden Waste, Neema Msuya Apr 2024

Production Of Biofertilizer From Fruit And Garden Waste, Neema Msuya

Tanzania Journal of Engineering and Technology (TJET)

The project focused on the production of bio-fertilizer from fruit and garden waste, with a specific emphasis on utilizing pineapple tops in the composting process. The objective was to produce and assess the properties of the bio fertilizer obtained from this process and evaluate its potential application in agriculture. In this study, the composting process was done in a 0.7 m long, 0.85 wide and 1.1 m high vessel, and 0.238 m3 pineapple top wastes, resulting in 0.35 m3 of biofertilizer. The bio fertilizer produced exhibited favorable characteristics, including a moisture content of 36%, pH of 7.1, and a total …


Causes And Consequences Of Inefficient Drilling And Blasting In Mine Development Headings: A Case Study Of Hard Rock Gold Mining Operations In Northern Tanzania, George Bennett Apr 2024

Causes And Consequences Of Inefficient Drilling And Blasting In Mine Development Headings: A Case Study Of Hard Rock Gold Mining Operations In Northern Tanzania, George Bennett

Tanzania Journal of Engineering and Technology (TJET)

Despite the introduction of the perimeter blasting technique at the Tulawaka Gold Mine, the mine continued to suffer from an overbreak of mine development headings, with an average overbreak of 24% every 22 m, which is approximately twice the acceptable 10% overbreak. The causes of this problem include ineffective drilling practices and uneven and excessive charging of explosives, resulting in a slightly high powder factor of 3.94 kg/m3 instead of 3.8 kg/m3, as per the design. The problem of overbreak resulted in ore dilution, a longer mine development cycle time and additional costs of approximately US$ 45 per cut, especially …


The Fourth Industrial Revolution: Opportunities And Challenges To The Future Of Mechanical Engineering, Ulingeta O.L. Mbamba Feb 2023

The Fourth Industrial Revolution: Opportunities And Challenges To The Future Of Mechanical Engineering, Ulingeta O.L. Mbamba

Tanzania Journal of Engineering and Technology (TJET)

This paper provides a conceptual overview of the developments of the Fourth Industrial Revolution (4IR) and derives challenges and opportunities for the future of the mechanical engineering profession. The paper broadly defines 4IR as the fusion of technologies and interaction across physical, digital and biological aspects, while defining mechanical engineering as "a multi-faceted discipline that encompasses the teaching, practice and guidance of others in the development and application of scientific principles to mechanical systems". The paper looks specifically at developments in the Internet of Things (IoT), blockchain technology, robotics, Big Data analytics, biotechnology, nanotechnology, 3D printing and artificial intelligence and …


Designing And Manufacturing Of Vegetable Slicing Machine, Juma Nuhu Msuya Feb 2023

Designing And Manufacturing Of Vegetable Slicing Machine, Juma Nuhu Msuya

Tanzania Journal of Engineering and Technology (TJET)

Agro-processing industry is faced with a challenge of slicing of vegetables for immediate consumption. This stems from the fact that the traditional slicing methods use bare hands, and knives. This method is faced with shortcomings of inefficiency, poor hygiene, and significant dangers to injury. If vegetables are not sliced, their drying takes longer, may possibly be spoiled, and cannot be stored for future uses. Therefore, this paper strives to design a vegetable slicing machine to increase the efficiency of the drying process as a post-processing step. The study employed a Pugh’s design model to design the machine and manufacture it. …


Impulse, Fall 2022, University Marketing And Communications, Jerome J. Lohr College Of Engineering Oct 2022

Impulse, Fall 2022, University Marketing And Communications, Jerome J. Lohr College Of Engineering

Impulse (Jerome J. Lohr College of Engineering Publication)

2 | Sanjeev Kumar Takes Helm as College’s 12th Dean
5 | College Develops Partnerships in India, Turkey
6 | Faculty News
8 | Aerofly — Profs, Alum Partner To Build Unique Drone
10 | Researchers Find Way to Extend Produce Shelf Life
12 | SDSU Claims National Title in Quarter-Scale Tractors
14 | Nation’s Top ASCE Chapter Housed at SDSU
16 | National Geo-Video Title Won By State Students
18 | Summer Brings Engineering Camps to Campus
20 | Haleigh Timmer — Money on the Court, In Classroom
22 | Daniel Burkhalter — Day in the Life of Student-Athlete …


A Model For Sustainable Adoption Of Solar Photovoltaic Technology In Tanzania, Joseph Kihedu Jun 2022

A Model For Sustainable Adoption Of Solar Photovoltaic Technology In Tanzania, Joseph Kihedu

Tanzania Journal of Engineering and Technology (TJET)

The aim of the study was to develop a sustainable model for enhancement of the solar PV technology adoption in Tanzania. The model was developed based on the identified barriers that hinder the adoption of solar PV technology and adopted the best strategies from successful projects. Further, the drivers and activities were developed based on selected best strategies from successful projects. The identified barriers to the adoption of solar PV technology, which are grouped into five associated categories and their significances, are lack of access to finance (32%), non-enforcement of policy and regulation (31%), technical (18%), lack of awareness (9%) …


Assessment Of Energy Efficiency In Beverage Industry, Mahamudu H. Mtebwa Jun 2022

Assessment Of Energy Efficiency In Beverage Industry, Mahamudu H. Mtebwa

Tanzania Journal of Engineering and Technology (TJET)

The brewery industry has a significant contribution to the national income. However, it is also associated with energy intensive processes and pollution. In this work, the energy efficiency assessment of the largest brewery in Tanzania i.e., Tanzania Breweries Limited has been conducted. Energy consumption analysis was conducted according to IEEE SA 739 1995. Important parameters used to assess brewery energy efficiency were boiler efficiency and losses, equipment energy productivity as well as load factor. It was found that the main energy consumers are packaging (54.63%), brewing (29.30%) and utilities (15.17%). More importantly, it was found that about 68% of the …


Production Of Paper Pulp Using Sisal Fiber Waste From Sisal Spinning Processes, Ekael Mbise Jun 2022

Production Of Paper Pulp Using Sisal Fiber Waste From Sisal Spinning Processes, Ekael Mbise

Tanzania Journal of Engineering and Technology (TJET)

Disposal of large volumes of textile waste is an escalating problem for textile industries. Sisal spinning industry is the one of the textile industries releasing large volumes of textile waste in the landfills. The rising costs, and reduction of available space together with increasing stringent environmental measures are making burying and land filling of textile waste, a declining option. This study therefore explores recycling options where the potential of using sisal fiber waste produced during sisal spinning processes as raw materials for the production of paper pulp was investigated. Sampling was done at 21stCentury Holdings Limited allocated at Chang’ombe industrial …


A Deep Reinforcement Learning Approach With Prioritized Experience Replay And Importance Factor For Makespan Minimization In Manufacturing, Jose Napoleon Martinez Apr 2022

A Deep Reinforcement Learning Approach With Prioritized Experience Replay And Importance Factor For Makespan Minimization In Manufacturing, Jose Napoleon Martinez

LSU Doctoral Dissertations

In this research, we investigated the application of deep reinforcement learning (DRL) to a common manufacturing scheduling optimization problem, max makespan minimization. In this application, tasks are scheduled to undergo processing in identical processing units (for instance, identical machines, machining centers, or cells). The optimization goal is to assign the jobs to be scheduled to units to minimize the maximum processing time (i.e., makespan) on any unit.

Machine learning methods have the potential to "learn" structures in the distribution of job times that could lead to improved optimization performance and time over traditional optimization methods, as well as to adapt …


Grinding And Super-Finishing Test Machine Project, Michael Simon Jan 2022

Grinding And Super-Finishing Test Machine Project, Michael Simon

Williams Honors College, Honors Research Projects

A research project in The University of Akron to study grinding and super-finishing of silicon nitride ceramic was initiated by Dr. Siamak Farhad and sponsored by the Timken Company, with the assistance of undergraduate students Michael Simon, Ryan Hosso and Mathew Rozmajzl. The study required analysis of forces and scratches generated during grinding processes of silicon nitride samples. A testing assembly was designed and constructed to record the forces generated during grinding and super-finishing of silicon nitride samples in a computer-numerical-control machine. Silicon nitride samples were subjected to desired grinding and super-finishing operations and all forces generated during the process …


Optimization In The Application Of Varnishes Barrier On Cartonboard Packaging, Andre Ramalheiro De Andrade, Maria Isabel Rodrigues Phd, Eduardo Luiz Machado Phd Oct 2021

Optimization In The Application Of Varnishes Barrier On Cartonboard Packaging, Andre Ramalheiro De Andrade, Maria Isabel Rodrigues Phd, Eduardo Luiz Machado Phd

Journal of Applied Packaging Research

In this work adjustments in the rotogravure printing process are proposed to the varnish water vapor transmission rate (WVTR) aiming to obtain results smaller than 20g/m²/24h. One case study was used for the propositions for improvements, where focused on varnish application process in a gravure printer for an eight-printing unit cartonboard packaging, maximum printing speed of 175 m/min and a 285 g/m² weight cartonboard. The possible variables that influenced the WVTR result were selected from the technical expertise of the people involved in the project, the analysis in the printing process with the application of directed trials using experimental designs …


Assessment Of The Impacts Of Climate Variability On Hydropower Generation: A Case Study Of The New Pangani Falls, Tanzania, Dativa Byarufu Jul 2021

Assessment Of The Impacts Of Climate Variability On Hydropower Generation: A Case Study Of The New Pangani Falls, Tanzania, Dativa Byarufu

Tanzania Journal of Engineering and Technology (TJET)

Climate change poses potential impacts on hydropower generation either positively by increasing or negatively by decreasing river flow. This study assessed the impacts of climate variability on hydropower with a focus on the New Pangani Falls in Tanzania. Rainfall and temperature time series data from 1980-2014 were analyzed in relation to river discharge and associated impacts to hydropower generation. The Man-Kendall test was used to detect trend in both annual and seasonal time series. The results showed a negative trend in annual rainfall with Z= -2.41 at α = 0.05 and the slope Q = -0.964. Seasonal trend analysis showed …


An Improved Earned Value Management Method Integrating Quality And Safety, Brian Briggs Jul 2021

An Improved Earned Value Management Method Integrating Quality And Safety, Brian Briggs

LSU Doctoral Dissertations

The construction industry invests significant time and money to improve quality and safety while reducing cost and schedule impacts. The industry has a sincere desire to improve construction project management methods to improve efficiency. Historically, quality and safety underperformances result from undermanaged quality control and safety activities. The cost and schedule impacts associated with poor quality work have always had an impact on construction operations. The unprecedented challenges and uncertainties of COVID-19 highlighted the need to improve the Earned Value Management (EVM) method within construction to reflect these quality and safety activities. The central goal of this dissertation is to …


Optimization Of Vaccine Supply Chains In Low- And Middle-Income Countries Utilizing Drones, Maximilian Kolter Jul 2021

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 …


Preventing Transmission Of Covid 19 In Hvac Duct Systems: Implementations Of Hvac System Design Upgrade, Jacob S. Lopez, Adama Barro Jun 2021

Preventing Transmission Of Covid 19 In Hvac Duct Systems: Implementations Of Hvac System Design Upgrade, Jacob S. Lopez, Adama Barro

Publications and Research

The recent pandemic outbreak has triggered a global alarm to increase efforts on finding the best methods to mitigate contagious viral pathogens. This project is a continuation of our mission to study engineering guidelines needed to implement upgrades to HVAC Systems in order to deter airborne pathogens such as the covid-19 virus. In our previous projects we researched how covid-19 can possibly flow through the ambient air inside of restaurants, office spaces, and locomotive train cabins. As we continued our research, we were able to find some solutions that will be best used to deactivate and prevent the virus from …


Development Of A Marine Biodegradable Target Balloon, Blake Samuel Robinson, Arash Sam Akhavi, David Leonardo Albarran-Martinez Jun 2021

Development Of A Marine Biodegradable Target Balloon, Blake Samuel Robinson, Arash Sam Akhavi, David Leonardo Albarran-Martinez

Materials Engineering

The US Navy utilizes PVC target balloons, known as Killer Tomatoes, that are inflated onboard a naval vessel then deployed into the ocean to calibrate a variety of weaponry. The Navy has requested the investigation of biodegradable polymers to replace the PVC in attempts to reduce ocean waste that is generated from the leftover PVC material. After communicating with American Pacific Plastic Fabricators (APPF), the current manufacturer of the Killer Tomatoes, we gained an understanding of the manufacturing process and the material requirements that would allow a new material to be integrated into their current process. Two proprietary, trial polymers …


Understanding Of Aerosol Transmission Of Covid 19 In Indoor Environment - Part 2: Approaches To Mitigation, Adama Barro, Cathal O'Toole, Jacob S. Lopez, Matthew Quinones, Sherene Moore May 2021

Understanding Of Aerosol Transmission Of Covid 19 In Indoor Environment - Part 2: Approaches To Mitigation, Adama Barro, Cathal O'Toole, Jacob S. Lopez, Matthew Quinones, Sherene Moore

Publications and Research

The challenge we face in implementing solutions for new HVAC ventilation and filtration design, is to effectively improve air quality for virus mitigation without losing performance efficiency. The purpose of this improvement is to decontaminate the occupied enclosed areas, reducing the transmission of the corona virus aerosol transmission. Our research seeks reliable approaches to mitigate the further spread of aerosol transmission in indoor spaces. The methodology is to examine innovative HVAC engineering solutions that combat epidemiological problems of Covid-19 for the post-pandemic era, by researching scholarly articles and ASHRAE journals. We are achieving the goal of finding highly efficient resolutions …


Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu Jan 2021

Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu

College of Graduate Studies: Theses & Dissertations

In recent years, lightweight structures have become mature and adopted in various applications. The importance of quality assurance cannot be overemphasized hence extensive research has been conducted to assess the quality of lightweight structures. This study investigates a novel process that exploits motion magnification to investigate the damage characteristics of lightweight mission-critical parts. The goal is to assure the structural integrity of 3D printed structures and composite structures by determining the inherent defects present in the part by exploiting their vibration characteristics. The minuscule vibration of the structure was recorded with the aid of a high-speed digital camera, and the …


In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain Jan 2021

In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain

College of Graduate Studies: Theses & Dissertations

Additive Manufacturing (AM) is currently a widely used technology in different industries such as aerospace, medical, and consumer products. Previously it was mainly used for prototyping of the products, but now it is equally valuable for commercial product manufacturing. More profound understanding is still needed to track and identify defects during the AM process to ensure higher quality products with less material waste. Nondestructive testing becomes an essential form of testing for AM parts, where AE is one of the most used methods for in situ process monitoring. The Acoustic Emission (AE) approach has gained a reputation in nondestructive testing …


A Framework For Using Fused Image Data In Statistical Process Control, Shengfeng Chen Aug 2020

A Framework For Using Fused Image Data In Statistical Process Control, Shengfeng Chen

Dissertations

The use of image data in manufacturing quality control systems has grown rapidly over the years. Technological advancements in imaging devices (e.g., digital cameras, x-ray scanners, infrared cameras) have provided convenient and cost-effective ways to obtain images. These images contain important quality features (e.g., textures and product dimensions) that can be used to monitor, diagnose, predict, and control manufacturing processes. A key tool for monitoring images is statistical process control charts. Integrating images of parts to detect process shifts can significantly improve a quality systems efficiency. Unfortunately, appropriate techniques that take full advantage of data-rich images for control charting are …


Designing An Adjustable And Transportable Staircase, Allison Currey Apr 2020

Designing An Adjustable And Transportable Staircase, Allison Currey

Undergraduate Honors Thesis Projects

People climb stairs every day, whether it is at work, a store, or at home; however, there are populations such as people who are elderly, with pathologies, with Parkinson’s disease, or have suffered from a stroke that see climbing the stairs as a challenging task and it decreases their mobility and quality of life. Factors such as muscle weakness, strategy, and balance have been previously investigated in these populations during stair climbing. However, few studies have researched how stair climb ability, balance, and perception of difficulty are influenced by step height. The objective of this thesis is to design a …


Subsurface Analytics: Contribution Of Artificial Intelligence And Machine Learning To Reservoir Engineering, Reservoir Modeling, And Reservoir Management, Shahab D. Mohaghegh Apr 2020

Subsurface Analytics: Contribution Of Artificial Intelligence And Machine Learning To Reservoir Engineering, Reservoir Modeling, And Reservoir Management, Shahab D. Mohaghegh

Faculty & Staff Scholarship

Subsurface Analytics is a new technology that changes the way reservoir simulation and modeling is performed. Instead of starting with the construction of mathematical equations to model the physics of the fluid flow through porous media and then modification of the geological models in order to achieve history match, Subsurface Analytics that is a completely AI-based reservoir simulation and modeling technology takes a completely different approach. In AI-based reservoir modeling, field measurements form the foundation of the reservoir model. Using data-driven, pattern recognition technologies; the physics of the fluid flow through porous media is modeled through discovering the best, most …


Kinematic Analysis Of Forehand Drop Shot And Long Shot Services In Table Tennis, Ibrahim Norzuria Feb 2020

Kinematic Analysis Of Forehand Drop Shot And Long Shot Services In Table Tennis, Ibrahim Norzuria

Student Works (2020-2029)

Table tennis is one of the most widely played sports in the world. A frequent hand movement is compulsory to execute stroke than other limbs, especially the projection of racket and ball speeds,which can help to improve players’ performance. Until now, research on table tennis serving is limited. Service was assumed important in table tennis because the effective serve may allow the serving player to have advantage and control over the game. The 3D dynamic analysis is the appropriate method to analyze a sport activity such as table tennis. Therefore, the aim of research was to determine the kinematic involved …


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


Development Of Bio-Based 2t Engine Oil In Marine Engine Application / Babooraman Shanmuganathan, Babooraman Shanmuganathan Jan 2020

Development Of Bio-Based 2t Engine Oil In Marine Engine Application / Babooraman Shanmuganathan, Babooraman Shanmuganathan

Student Works (2020-2029)

Two-storke enginers are simple and lightweight two-cycle spark ignition engine with no oil sump is needed. The use of bio-based lubricants was analyzed to replace commercial mineral and synthetic-based lubricants. Lubricants were prepared by mixing three components of oil which comprise of base oil, additives, and solvent. In this research, four samples of base oil had been prepared with a different weight ratio of the PFAD-NPGester and Type II mineral. Then each of the simples were added with a similiar weight ratio of additives and solvent. A commercial lubricant was used as areference lubricant to be compared with samples prepared. …


The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1 Dec 2019

The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1

Tanzania Journal of Engineering and Technology (TJET)

Worldwide, every day human beings generate millions of tons of Faecal Sludge (FS), which is rich in water, nutrients, energy, and organic compounds. Yet FS is not being managed in a way that permits us to derive value from its reuse, while at the same time, millions of farmers struggle with depleted soils and lack of water. In most of the developing countries, energy for cooking is mainly derived from cutting of trees, either as wood or charcoal. Resource recovery and reuse from FS can create livelihoods, enhance food security, support green economies, reduce waste and contribute to cost recovery …


Optimizing Block-Stacking Operations With Relocation, Hueon Lee Dec 2019

Optimizing Block-Stacking Operations With Relocation, Hueon Lee

Graduate Theses and Dissertations

The focus of the dissertation is developing the optimization problem of finding the minimum-cost operational plan of block stacking with relocation as well as devising a solution procedure to solve practical-sized instances of the problem. Assuming changeable row depth instead of permanent row depth, this research is distinguished from conventional block stacking studies.

The first contribution of the dissertation is the development of the optimization problem under the assumption of deterministic demand. The problem is modeled using integer programming as a variation of the unsplittable multi-commodity flow problem. To find a good feasible solution of practical-sized instances in reasonable time, …


Literature Survey Of Wet-Waste And Hydrothermal Carbonization System: A Comparative Evaluation, Ramat Olaide Yusuf Jan 2019

Literature Survey Of Wet-Waste And Hydrothermal Carbonization System: A Comparative Evaluation, Ramat Olaide Yusuf

Dissertations and Theses

This thesis describes the process of Hydrothermal carbonization and a comparative assessment on recent work done on the process using different feedstocks such as Raw Apple (RA), Apple chip pomace (ACP), apple juice pomace (AJP), grape pomace (GP), macadamia nut-shell (MNS), Sewage Sludge (SS), Poultry Litter (PL) and Grape Marc (GM). The data obtained from the literature survey was compared with the data obtained by the CCL team on the SWPS gasifier (HTC of poultry litter) to obtain how carbon conversion efficiency, syngas composition, thermal efficiency, char production rate, gas production rate and energy utilization vary with carbonization process conditions, …


Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto Jan 2019

Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto

Engineering and Technology Management Faculty Publications and Presentations

Purpose – The establishment of partnerships between companies, government and universities aims to enhance innovation and the technological development of institutions. The biotechnology sector has grown in recent years mainly driven by its cooperative business model. Compared to other countries, this sector is slowly advancing in Brazil, with delays in science, technology and innovation, especially in the private sector. This paper aims to examine, through social network analysis, the collaborative networks between institutions that filed patents in biotechnology – medicinal preparations from plants – whose inventions had Brazil as the priority country. Design/methodology/approach – The study of technological cooperation using …


Reliability Estimation Of Reciprocating Seals Based On Multivariate Dependence Analysis And It's Experimental Validation, Chao Zhang, Rentong Chen, Shaoping Wang, Yujie Qian, Mileta M. Tomovic Jan 2019

Reliability Estimation Of Reciprocating Seals Based On Multivariate Dependence Analysis And It's Experimental Validation, Chao Zhang, Rentong Chen, Shaoping Wang, Yujie Qian, Mileta M. Tomovic

Engineering Technology Faculty Publications

Accurate reliability estimation for reciprocating seals is of great significance due to their wide use in numerous engineering applications. This work proposes a reliability estimation method for reciprocating seals based on multivariate dependence analysis of different performance indicators. Degradation behavior corresponding to each performance indicator is first described by the Wiener process. Dependence among different performance indicators is then captured using D-vine copula, and a weight-based copula selection method is utilized to determine the optimal bivariate copula for each dependence relationship. A two-stage Bayesian method is used to estimate the parameters in the proposed model. Finally, a reciprocating seal degradation …