(R2120) Flexible Group Service Map/Ph/1 Queueing Model With Working Vacation And Optional Service,
2025
Puducherry Technological University
(R2120) Flexible Group Service Map/Ph/1 Queueing Model With Working Vacation And Optional Service, G. Ayyappan, S. Kalaiarasi
Applications and Applied Mathematics: An International Journal (AAM)
There are many uses of queues, where services are provided in groups; these types of queues are widely studied in the literature. In this paper we examine a particular queueing model wherein the services are provided in groups and the group size may be less than or equal to the size initially fixed. The arrival follows a Markovian arrival process. The service time of each individual customer follows phase type distribution. The maximum of each customer’s individual service time within a group is defined as the group’s service time. At the service completion moment if there are fewer customers than …
Condition Optimization For The Synthesis Of Castor Oil Templated Mesoporous Silica,
2025
Department of Chemistry, Faculty of Science, Mkwawa University College of Education, University of Dar es Salaam, P.O. Box 2513, Iringa, Tanzania
Condition Optimization For The Synthesis Of Castor Oil Templated Mesoporous Silica, Godlisten Namwel Shao
Tanzania Journal of Engineering and Technology (TJET)
The present work provides suitable conditions for the synthesis of mesoporous materials with improved porosity using an optimization technique. The proposed preparation method involves forming final products by varying the amount of castor oil, media, and template removal. The obtained samples were examined by TGA, XRD, DRIFT and nitrogen physisorption studies. It was observed that the porosity of the obtained samples was dependent on the conditions under which the materials were synthesized. All synthesized materials showed the Type IV adsorption-desorption isotherm features of mesoporous, regardless of the conditions utilized during the synthesis. The sample synthesized using 2.5 g of a …
Adoption Of Agrivoltaics In Developing Countries: A Review On Challenges, Opportunities And Future Prospects,
2025
Department of Electrical Engineering, University of Dar es Salaam, P.O. Box 33335, Dar es Salaam, Tanzania
Adoption Of Agrivoltaics In Developing Countries: A Review On Challenges, Opportunities And Future Prospects, Abdi J. Athumani, Pater Makolo
Tanzania Journal of Engineering and Technology (TJET)
This paper provides a review of agrivoltaics technology and how it has been applicable in developing countries, including African countries. Agrivoltaics, the integration of agricultural production with photovoltaic energy generation, offers promising solutions to water- energy-food nexus in developing countries. This technology offers the dual benefit of increasing agricultural productivity while generating clean energy, which is very important for regions facing frequent electricity shortages and declining agricultural yields due to climate change. However, despite its potential, the adoption of agrivoltaics in developing nations remains limited in comparison to developed countries due to financial, technical and policy constraints. This paper explores …
Cnn-Based Hybrid Model For Detecting Blight Diseases In Potato Crops With Advanced Image Processing Techniques,
2025
Department of Informatics and Information Technology, College of Natural and Applied Sciences, Sokoine University of Agriculture, P.O. Box 3000, Morogoro, Tanzania
Cnn-Based Hybrid Model For Detecting Blight Diseases In Potato Crops With Advanced Image Processing Techniques, Farian S. Ishengoma
Tanzania Journal of Engineering and Technology (TJET)
Potato production plays a vital role in global agriculture as a major food source for large populations. However, potato crops are highly susceptible to diseases, particularly Early Blight and Late Blight, which result in substantial yield losses. Timely detection and effective control of these diseases are essential for maintaining stable crop output. This study explores the integration of Convolutional Neural Networks (CNNs) and advanced image processing techniques to differentiate between diseased and healthy potato plants accurately. Two datasets comprising original and enhanced images were used to train four CNN models: InceptionV3, Xception, Densenet201, and Resnet152V2. The original images underwent background …
Resilience Engineering Via Bifurcation And Ecological Network Analysis: Demonstrated In An Electric Power Case Study,
2025
Embry-Riddle Aeronautical University
Resilience Engineering Via Bifurcation And Ecological Network Analysis: Demonstrated In An Electric Power Case Study, Rogelio Gracia Otalvaro
Doctoral Dissertations and Master's Theses
Modern systems are increasingly complex, interconnected cyber-physical systems that combine digital controls with physical infrastructure. This integration, along with the constant introduction of new technologies and actors into the network, enables reliable operation but introduces vulnerabilities to unexpected and varied disruptions and cascading failures, making resilience a critical concern. Traditional risk management and resilience assessment methods often struggle with the nonlinearity and dynamic behavior of these systems. This dissertation proposes a novel approach combining Bifurcation Analysis (BA) and Ecological Network Analysis (ENA) to enhance the understanding and improvement of system resilience. BA, a mathematical method from dynamical systems theory, is …
A Review Of The United States' Long Term War Support Capabilities In The Indo-Pacific Command Region,
2025
Air Force Institute of Technology
A Review Of The United States' Long Term War Support Capabilities In The Indo-Pacific Command Region, Brian J. Mullin Jr.
Theses and Dissertations
This study examines U.S. maritime transportation readiness in the Indo-Pacific, highlighting fleet age, mariner shortages, shipyard decline, and port vulnerabilities. It also considers contested logistics and technological threats. Recommendations include fleet recapitalization, mariner pipeline growth, port diversification, and defensive upgrades. The study concludes that secure sea line assumptions are outdated and calls for greater resilience, with follow-on efficiency analysis proposed for ports and ships.
Effects Of Variation In Altitude And Temperature On The Restraining Force And Internal Gauge Pressure Of Constrained Dunnage Airbags,
2025
Clemson University
Effects Of Variation In Altitude And Temperature On The Restraining Force And Internal Gauge Pressure Of Constrained Dunnage Airbags, Charles R. Weaver
All Theses
Dunnage airbags are an increasingly popular choice for securing cargo. During transit, changes in ambient temperature and pressure can cause airbags to expand generating damaging horizontal compressive forces in the trailer or container. Previous studies have developed numerical models for the behavior of Kraft paper and woven polypropylene fabric dunnage airbags under standard conditions but do not account for the behavior of airbags under varied altitudes and temperatures. This study provides empirical data on the internal gauge pressure and restraining force dynamics of 4-ply Kraft, woven polypropylene, and polyvinyl chloride airbags under simulated altitude and temperature conditions. Tensile testing characterizes …
Understanding The Elements Of Sterile Processing Workflow: Or, Sterilization And Personnel,
2025
Clemson University
Understanding The Elements Of Sterile Processing Workflow: Or, Sterilization And Personnel, Sayed Rezwanul Islam
All Dissertations
The Sterile Processing Department (SPD), also known as the Central Sterile Services Department (CSSD), is an essential part of hospitals and healthcare facilities and is responsible for ensuring the cleanliness, sterility, and proper functioning of medical instruments. Sterile processing departments (SPDs) are key drivers of productivity, effectiveness, safety, and infection control in hospitals. A well-designed SPD workflow can enhance patient safety, reduce operating room (OR) delays, and improve productivity. To understand the flow of sterile processing and interactions between the OR and SPD, process maps and task analyses were developed through direct observations of the basic SPD functions: decontamination, assembly, …
Algorithms For Combined Regular Synthesis Of Controller Parameters In Control Systems For Dynamic Objects,
2025
Tashkent State Technical University, Tashkent city, Republic of Uzbekistan, DSc, Professor, Academic, https://orcid.org/0000-0003-3047-5261
Algorithms For Combined Regular Synthesis Of Controller Parameters In Control Systems For Dynamic Objects, Khusan Zakirovich Igamberdiev, Latafat Abbas Gizi Gardashova, Yulduz Mukhtarkhodjayevna Abdurakhmanova, Uktam Farkhodovich Mamirov
Technical science and innovation
Nonlinear control system that includes m-dimensional input control signal and extended (n+s) - dimensional state vector, the last s components of which form a vector of unknown parameters θ satisfying a general difference equation is being considered. The quality criterion is determined by the loss function. The optimal control must satisfy the Bellman equation with respect to the optimal loss function. To be defined an approximate solution that preserves an active use of information. For this purpose, the system is linearized in accordance to the nominal trajectory. This problem is seen as incorrectly stated. The values of the preliminary data …
Navigating Perceptions: How Organizational Type And Message Source Affect Willingness To Fly In Automated Air Taxis,
2025
Embry-Riddle Aeronautical University
Navigating Perceptions: How Organizational Type And Message Source Affect Willingness To Fly In Automated Air Taxis, Cody James Sweatt
Doctoral Dissertations and Master's Theses
A new era of transportation and business is beginning to emerge. Advanced air mobility (AAM), which uses highly automated aircraft that transport passengers and cargo in the underutilized, low-altitude airspace above and around urban areas, is rapidly becoming a reality (FAA, 2023). These new companies will utilize air taxis, which are automated, electric, vertical takeoff and landing (eVTOL) aircraft and will potentially foster a revolutionary new commerce infrastructure. Unfortunately, it is not currently understood how the credibility of a message source or specific type of organization that owns and operates an automated air taxi company influences a customer’s willingness to …
Comparative Analysis Of The Efficiency Of Reverse Osmosis And Hydroxyapatite For Fluoride Removal In Water: A Case Of Auwsa,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania
Comparative Analysis Of The Efficiency Of Reverse Osmosis And Hydroxyapatite For Fluoride Removal In Water: A Case Of Auwsa, Innocent J. Macha
Tanzania Journal of Engineering and Technology (TJET)
Water treatment technology selection depends on contaminant type and budget. Fluoride removal from water is particularly challenging, requiring non-conventional treatment technologies (Radwan, 2023). Several regions in Tanzania, including Arusha City, are affected by fluoride contamination. With a population of 617,631 (Census, 2022), only 117,763 people currently have access to clean water supplied by AUWSA. This study aimed to compare the efficiency of Reverse Osmosis (RO) and Hydroxyapatite (HAP) in fluoride removal as a strategy to address water quality and supply challenges. Experiments were conducted using 6 m³ of raw water with fluoride concentrations ranging from 5.1 mg/L to 6.83 mg/L, …
Strategies For Overcoming Product Certification Challenges Faced By Food Manufacturing Small And Medium Enterprises In Tanzania,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania
Strategies For Overcoming Product Certification Challenges Faced By Food Manufacturing Small And Medium Enterprises In Tanzania, Peresi M. Bulemo
Tanzania Journal of Engineering and Technology (TJET)
Small and Medium-sized Enterprises (SMEs) in Tanzania face significant regulatory challenges within bureaucratic, costly, and centralized environments. These challenges contribute to an increase in unregistered enterprises and substandard products in the market. This study aimed to address the challenges SMEs encounter in obtaining product certification to improve their product quality and market competitiveness. A mixed-methods approach was employed, combining qualitative and quantitative research through surveys, interviews, and document analysis, with respondents from the Tanzania Bureau of Standards (TBS), Small Industries Development Organization (SIDO), and SMEs in the food manufacturing sector. Data analysis was conducted using SPSS and JASP. Findings revealed …
Prospects Of Clean Cooking Energy In Africa - Transition Pathways And Implications,
2025
University of Dar es salaam
Prospects Of Clean Cooking Energy In Africa - Transition Pathways And Implications, Joseph H. Kihedu Dr.
Tanzania Journal of Engineering and Technology (TJET)
Despite abundant renewable energy resources, African countries still suffer from energy poverty, particularly in cooking. Up to 2022, about 74% of the African population had no access to clean cooking energy. With focus to Sub-Saharan African population, 90% has no access to clean cooking energy which decrease by 7% when kerosene is included. Traditional cooking, which involves the use of charcoal and firewood, is associated with health problems, environmental degradation, socioeconomic issues, and gender inequality. Transitioning to clean cooking energy not only promises significant health benefits but also offers opportunities for sustainable economic development and environmental preservation. In this study, …
Towards Metrology 4.0 In Developing Countries’ Manufacturing Industries,
2025
Department of Legal and Industrial Metrology, College of Business Education, P.O Box 1968 Dar es Salaam, Tanzania
Towards Metrology 4.0 In Developing Countries’ Manufacturing Industries, Jailos Nzumile
Tanzania Journal of Engineering and Technology (TJET)
A systematic literature review was conducted to unveil the status of the digital transformation of metrology in developing countries, as they are lagging in utilising fourth industrial revolution (IR4.0) technologies to transform manufacturing industries. A PRISMA technique was employed using various keywords to identify, screen, and select the relevant literature. Forty publications were selected for the review, mainly discussing IR 4.0 technologies in metrological operations. The results indicate that the digital transformation of metrology has yet to be initiated in developing countries. However, the employment of IR4.0 technologies in advancing metrological operations in manufacturing industries is mostly discussed in the …
Comprehensive Review Of Sensible Thermal Storage Systems For Cooking Applications,
2025
Department of Energy and Process Engineering, Norwegian University of Science and Technology, Norway
Comprehensive Review Of Sensible Thermal Storage Systems For Cooking Applications, Anna K. Shariishoy
Tanzania Journal of Engineering and Technology (TJET)
This paper reviewed the sensible thermal storage systems specifically designed for cooking applications. The review focuses on the characteristics of storage materials, their practical applications, and the overall performance of the systems. The review consolidated an array of experimental and numerical research published across various sources such as journals, conferences, books, online resources, and professional reports. A systematic review is used to reach the conclusion of this paper. Significant findings from this study include the wide range of storage capacities attained from small-scale systems that can store ~1–5 MJ of energy for a single meal to bigger systems that can …
Fuzzy Logic-Based Decision Support System For Adoption Of Industry 4.0 Predictive Maintenance By Manufacturing Industries,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania
Fuzzy Logic-Based Decision Support System For Adoption Of Industry 4.0 Predictive Maintenance By Manufacturing Industries, Fred E. Peter
Tanzania Journal of Engineering and Technology (TJET)
In the context of Industry 4.0, predictive maintenance enhances operational efficiency by optimizing processes, minimizing downtime, and improving cost-effectiveness. However, implementing predictive maintenance requires a systematic approach due to its complexity. This study collected expert input from 15 food and beverage manufacturing industries located in Dar es Salaam, Tanzania, using a purposive sampling technique. Six representatives were selected from each industry, and their opinions were analyzed using MATLAB 7.6 through a fuzzy logic inference system. The analysis focused on key factors influencing Industry 4.0 technology adoption for predictive maintenance, including adoption intention (strategic decision, equipment data, perceived benefit) and perceived …
Mechanical Properties Of Pineapple Braided Fabric Reinforced Epoxy Matrix Composite Fabricated Via Vacuum-Assisted Resin Infusion Moulding,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania.
Mechanical Properties Of Pineapple Braided Fabric Reinforced Epoxy Matrix Composite Fabricated Via Vacuum-Assisted Resin Infusion Moulding, Bwire S. Ndazi
Tanzania Journal of Engineering and Technology (TJET)
Fibres and fabrics obtained from lignocellulosic materials have attracted attention as reinforcements in polymer composites due to their competitive mechanical and ecological benefits. While the potential of randomly oriented pineapple leaves fibres (PALF) in composites have explored in previous studies, the mechanical behaviour of braided PALF fabric composites fabricated via vacuum-assisted resin infusion moulding (VARIM) remains relatively unexplored. In this study the tensile, compression and flexural strengths of epoxy-based composite containing 40 vol.% braided pineapple fabrics, fabricated using VARIM, for load carrying applications were investigated. The results revealed that the three-layered unbleached pineapple braided fabric composites exhibited a tensile strength …
The Role Of Internal Factors On Vehicular Mobility,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania
The Role Of Internal Factors On Vehicular Mobility, Aziz Mdimi
Tanzania Journal of Engineering and Technology (TJET)
Vehicle mobility internal factors are influenced by the performance state of the road surface quality, governor, engine, gear train, differential unit and mobility unit. Studies on vehicular mobility models exist for off-road external factors but absent on on-road internal factors. The on-road internal factors model describes the vehicular mobility performance as a function of internal factors. In the current undertaking, results are generated by the determination of mobility performance characteristics with the application of 2nd Order Ordinary Differential Equations and using Laplace operator with MATLAB Software simulation. The effect of road surface against the time taken varies accordingly. At a …
Towards Effective Academia-Industry Collaborations: The Case Of Higher Learning Institutions In Tanzania,
2025
Department of Computer Sciences and Engineering, University of Dar es Salaam, P.O. Box 33335, Dar es Salaam, Tanzania
Towards Effective Academia-Industry Collaborations: The Case Of Higher Learning Institutions In Tanzania, Fatuma S. Ikuja
Tanzania Journal of Engineering and Technology (TJET)
Industries are the main consumers of products from higher learning institutions (HLIs); graduates for employment and research outputs for socio-economic development. Research outputs from HLIs are commercialized as services or products facilitated by academia-industry collaborations. The collaborations are expected to address mismatch between labour market needs and HLIs’ products, which has resulted in graduates’ employability challenges. Despite their importance, effective academia-industry collaborations remain challenging. This study explores the effectiveness of Academia-Industry collaborations established by HLIs in implementing the Higher Education Economic Transformation (HEET) project (2021-2026) in Tanzania. One of the project objectives is to build functional linkages between industry and …
Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works,
2025
Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O Box 35131, Dar es Salaam, Tanzania
Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works, George C. Haule
Tanzania Journal of Engineering and Technology (TJET)
This study aimed to investigate the vital role and impact of technical audits in promoting sustainable infrastructure development in Tanzania. The role and effects of technical audits in long-term infrastructure development were studied using a mixed-methods approach with both quantitative and qualitative parts. Data were collected through analysis of technical audit documentation, a semi-structured questionnaire, and stakeholder interviews. The study revealed the various dimensions of infrastructure investment projects, including initiation and planning, design, procurement of contractors and consultants, contract management, environment, health, and safety. The technical audit findings reported weaknesses or non-performance issues in infrastructure planning at the national level …
