Digital Commons Network^™

Fuzzy-Ahp Based Decision Support System For The Selection Of Optimal Maintenance Strategy For Meter Gauge Railway Infrastructure: A Review, Hamisi J. Maulid

Tanzania Journal of Engineering and Technology (TJET)

There are many uncertainties and complexities associated with maintaining Meter Gauge Railway (MGR) infrastructure, which calls for a methodical approach to decision-making. The development and application of a fuzzy-AHP-based decision support system (DSS) to select the optimal maintenance strategy for the MGR are presented in this study. The review covers research from 2013 to 2023 and focusses on the use of Multi-Criteria Decision Making (MCDM) and Fuzzy Analytic Hierarchy Process (Fuzzy-AHP) techniques in railway infrastructure maintenance. To manage the inherent uncertainties and subjective judgements involved in maintenance decision-making, the Fuzzy-AHP methodology combines fuzzy logic with the Analytic Hierarchy Process (AHP). …

The Impacts Of Renewable Energy Sources: A Review On Grid Inertia And Frequency Regulation, Sospeter Gabriel

Tanzania Journal of Engineering and Technology (TJET)

The power system is gradually transitioning into low inertia due to integrating substantial intermittency quantity of converter-based renewable energy sources, such as wind and photovoltaic power, into the current power grid network. This integration presents significant inertia and frequency control challenges to the network as a result of a decrease in the percentage of synchronous generators. Moreover, faster frequency deviations are posed by the mismatch between the supply and demand during contingencies, which creates difficulties in preserving the frequency stability of the power system. This research explores the impacts of renewable energy sources (RESs) on grid inertia and frequency management …

Predicting The Influence Of Aggregate Size And Distribution On Cementitious Concrete Properties: A Review, Innocent J. Macha

Tanzania Journal of Engineering and Technology (TJET)

Cement concrete has been in use for centuries as one of the primary construction materials. Its demand in the construction industry is expected to continue for several centuries before the full development of alternative products. However, one of the main areas of research interest is understanding how its constituents can be tailored to make its properties predictable to reduce risks associated with structural failures, reconstruction and reduced durability. These hindrances associated with cementitious concrete result from several attributes, including constituent material characteristics, mixing ratios and workmanship. Understanding the predictability of cement concrete properties requires computer modelling tools to provide reliable …

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 …

Optimizing The Processing Temperature For Synthesis Of Silver Nanoparticles Within Cellulose-Wool Keratin Supramolecular Matrix Using Butylmethylimmidazolium Chloride Ionic Liquid, Ngesa E. Mushi

Tanzania Journal of Engineering and Technology (TJET)

To date, the synthesis of silver nanoparticles on the surface of cellulose and wool keratin biopolymer, while dissolved in ionic liquid, is attractive because of its biomedical potential. However, the optimal processing temperature for the nanoparticle formation is unclear. The previously reported temperature of approximately 120°C gives unpredictable results. The current study employs a combination of 50% cellulose and 50% keratin, along with 69 mg of silver chloride, in Butylmethylimidazolium Chloride BMImCl ionic liquid, using a single-pot process to produce a supramolecular film via non-derivatized mechanochemical interactions. The primary objective is to experimentally establish the processing temperature to achieve stable …

Fabrication Of A Pineapple Peeling Machine And Performance Evaluation As Influenced By Pineapple Dimensions, Dare E. Ibiyeye, Olusegun J. Adedipe, Oluwole S. Ariwoola, Taiye R. Afolabi, Funmilayo B. Okanlawon, Paul O. Ogunbamowo, Afolake E. Roberts

Journal of Bioresource Management

A pineapple peeling machine was completed, and the functionality was. The Central composite rotate strategy CCRD involving three variables at five (5) stages was employed for the investigations plus the investigational variables been weight, diameter and height of pineapple, while weights of peeled pineapple and peel, machine peeling time and efficiency were the dependent variables. Data was analysed using quadratic interaction regressions model at P ≤ 0.05 levels of significance, then the working variables were correlated to the pineapple machine peeling efficiency. The investigational outcomes were applied to confirm the predicted optimal settings. Maximal pineapple peeling efficacy of 91.89 % …

Effect Of Sorbitol Plasticizer On Bioplastics Properties Based On Oil Palm Empty Fruit Bunches (Opefb) And Jackfruit Seed Starch, Nia Sasria, Vita Nur Afifah, Gusti Umindya Nur Tajalla

Makara Journal of Science

In bioplastics, natural materials that are easily decomposed are used to minimize plastic waste. In this research, the compositions used were cellulose from oil palm empty fruit bunches (OPEFB), jackfruit seed starch, and carboxymethyl cellulose (CMC) as a filler with sorbitol as a plasticizer. This study aimed to analyze the effect of a sorbitol plasticizer on bioplastic properties. The study began by extracting jackfruit seed starch and OPEFB cellulose. Subsequently, bioplastics were prepared by varying sorbitol, namely 0 (S – 0), 0.5 mL (S – 0.5), 1 mL (S – 1), and 1.5 ml (S – 1.5), with CMC 20%. …

The Importance Of The Analog-To-Digital Converter In The Measurement System, Aliev Ravshan, Anvar Djalilov

Chemical Technology, Control and Management

At the moment, many scientific researches are being conducted all over the world on the economical use of water and energy resources. Most of the scientific research works are aimed at improving measurement techniques and technologies, that is, increasing their accuracy. With this in mind, a high-precision analog-to-digital converter due to its unique metrological and technical characteristics was studied in this research paper. As a result of the study, it became clear that the use of a small-sized, high-precision sigma-delta analog-to-digital converter in modern measuring technology has a positive effect on its accurate and efficient operation.

Optimisation Of Astatic Controllers In Automatic Control Systems, Isamiddin Xakimovich Siddikov, Dilnoza Maxamadjanovna Umurzakova

Chemical Technology, Control and Management

This article examines the influence of various factors on the efficiency of optimizing station controllers in automatic control systems. The main focus is on minimizing static errors and improving the reliability of controllers. Optimization methods for PID and PI²D controllers are discussed, including the use of modern approaches such as genetic algorithms. The necessity of compromise solutions to achieve high-quality system responses to various impacts is investigated. It was also suggested that there is a need for an integrated approach to setting up controllers in order to increase their reliability and flexibility in conditions of dynamically changing processes. …

Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski

Journal of Electrochemistry

This feature article illustrates the potential of polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) to provide molecular-level information about the structure, orientation and conformation of constituents of thin films at electrode surfaces. PM IRRAS relies on the surface selection rules stating that the p-polarized IR beam is enhanced, while the s-polarized beam is attenuated at the metal surface. The difference between p- and s-polarized beams eliminates the background of the solvent and provides IR spectra at a single electrode potential. In contrast, two other popular in situ IR spectroscopic techniques, namely, subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS) …

Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin

Journal of Electrochemistry

A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing. The necessity for its sophistication arises from the availability of multi-dimensional sensing signals. Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sensitivity and selectivity. This study aimed to elucidate the modification of an indium tin oxide (ITO) electrode with a viologen monolayer with an ordered orientation. Novel methods were developed to immobilize a viologen molecule bearing a carboxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide with N-hydroxy-succinimide (EDC/NHS). In the two methods …

Logistical Automation In Hospitals In The Dach Region And Approaches To Increasing Process Efficiency Through Automation, Emily C. Spicker, Sabrina Forster, Sonja Stabenow, Sidra Rashid, Johannes Fottner, Dirk Wilhelm

International Material Handling Research Colloquium

No abstract provided.

Store-By-Voice: A Voice-Controlled Putaway And Stocktaking System, Thorsten Schmidt, Heiner Ludwig, Mathias Kühn

International Material Handling Research Colloquium

No abstract provided.

Development Of Mechanical Transfer Station For Automated Transport Robots, Stefan Galka

International Material Handling Research Colloquium

No abstract provided.

Reusing Materials In The Aerospace Industry, Lama Alanazi, Burtegeljin Gombosuren, Byhalia Jewett

Beyond: Undergraduate Research Journal

This research explores the material recycling methods used by the aerospace industry, particularly in comparison to the reusability of aerospace materials and with the objective to find uses for recycled materials from aircraft. Through an analysis of various other material mitigation methods, it is apparent that the physical degradation of materials after they go through recycling processes and the cost of recycling are the most prominent issues holding the aerospace industry back from being able to recycle aircraft up to 100%. From a comparison of physical characteristics of materials after reprocessing, several materials were found to meet industry standards, while …

A Yolo-Based Deep Learning Approach For Vibration-Based Rotating Shaft Imbalance Detection, Abdelhameed Zayed Dr., Ali Siam Dr.

Journal of Engineering Research

One of the prevailing causes of vibrations in machines is rotor imbalance. Rotor balancing can be used to fix the majority of rotating machinery issues. When it comes to high-speed running equipment, even a slight imbalance can lead to serious issues and decrease the operational efficiency of rotating machinery. This work proposed a deep learning approach for the detection of binary and multiclass imbalance in rotating shafts. A YOLOv11 model-based approach is developed to detect imbalance and identify unbalanced rotor positions. To precisely identify unbalanced positions, this method trains the YOLOv11 model using numerous sets of measured response data and …

Machine Learning-Based Prediction Of Load Capacity In Corrugated Concrete-Filled Double Skin Tubes Under Axial Load, Aya Mohsen Handousa Mansoura University, Fikry Salem, Nabil Mahmoud Mahmoud, Mohamed Ghannam

Journal of Engineering Research

Concrete-filled double-skin steel tubular (CFDST) columns have become widely utilized in building construction and bridges, thanks to their exceptional structural capabilities. This study investigates the axial compression behavior of corrugated CFDST columns, analyzing the impact of flat or corrugated external/internal plates and varying internal steel tube widths. Furthermore, basic regression analysis fails to precisely forecast the complicated relation between the column properties and their compressive strength. To overcome these challenges, this study suggests two machine learning (ML) models, including the Gaussian process (GPR) and the extreme gradient boosting model (XGBoost). To estimate their strength, these models employ a range of …

An Engineering Solution For Fan Aeroacoustics Measurements Correction In A Non-Anechoic Testing Environment, Saad-Eldin Taha, Mohamed Y.Zakaria, Mohamed Abdelgaied, M.M. Bassuoni Prof. Dr.

Journal of Engineering Research

Abstract- Nowadays, acoustic signatures of daily used applications are to be minimized. The study of noise generated through aerodynamic interaction with moving bodies has passed through different phases since the early 50s, and this leads to the evolvement of many analytical, empirical and computational techniques in order to be able to estimate the emitted noise. Concerning fan blades, until now the researches are still going for a reliable method for noise estimation during the early phases of design which help in the development of blades with a lower aeroacoustic signature, the Brooks, Pope and Marcolini (BPM) model was chosen to …

Evaluating The Role Of Building Information Modeling (Bim) In Minimizing Delays And Reducing Costs In Construction Projects, Hussein Elsayed Mohamed Ismail, Mohammad Ahmad Mohammad Abdulhadi

Journal of Engineering Research

The implementation of Building Information Modeling (BIM) as a construction industry technology delivers extensive effects on project duration and financial management. This investigation examines BIM as a technology specifically designed to cut down construction project delays and decrease expenditures. The scholarly review of existing research material through a secondary approach allows this study to identify BIM's major value contributions.

The implementation of BIM technology enables project schedules to reach improved accuracy which results in a reduction of project delays by 15-25% because of its automation features and effective clash detection and real-time coordination benefits. The application of building information modeling …

Multi-Modal Covid-19 Detection Using Cough Sounds And Medical Information With Attention-Enhanced Deep Learning, Mohamed Talaat Saidahmed, Reda Elbasiony, Marwa Reda Bastwesy, Asmaa Aly Hagar

Journal of Engineering Research

The COVID-19 pandemic has highlighted the need for fast, non-invasive, and cost-effective diagnostic tools. Cough sounds, as a prominent symptom of respiratory diseases, present a promising modality for automated COVID-19 detection. In this study, we propose a novel multi-modal deep learning framework for COVID-19 detection that leverages cough sounds and patient-specific medical information. Our approach extracts two types of acoustic features—Mel-Frequency Cepstral Coefficients (MFCCs) and Mel spectrograms—and integrates them with clinical metadata to improve diagnostic ac-curacy. The MFCC branch employs 1D convolutional layers followed by Efficient Channel Attention mechanism. The Mel spectrogram branch utilizes ResNet-50 combined with ECA to capture …

A Comprehensive Review Of Carbonation In Supplementary Cementitious Concrete: Factors Affecting, Measurement Methods, And Challenges, Mariam Farouk Ghazy, Metwally Abd Allah Abd Elaty, Esraa Samir Abdeljalil

Journal of Engineering Research

Abstract-After water, concrete is the most widely used material on the planet. Accelerated carbonation treatment is an effective approach of reducing carbon emission in the concrete industry. Such carbonation process converts gaseous CO2 into carbonated minerals. This review provided a special focus on internal and external variables affecting carbonation depth. Internal variables such as mixture components, External variables such as adding pozzolanic materials such as fly ash, and slag were examined systematically, temperature, pressure, and CO2 concentration. The effect of accelerated carbonation curing on the compressive strength of concrete at early ages, both positive and negative influences were identified. …

Mutual Coupling Impedance Effect On Ris-Assisted Terahertz Communication, Radwa A. Roshdy Dr., Hossam M. Kasem Prof., Mohammed A. Salem Dr.

Journal of Engineering Research

Terahertz (THz) communication based on reconfigurable intelligent surfaces (RIS) is a promising technology in future wireless networks, with the capabilities of ultra-high data rates and energy-efficient beam communicating. Nevertheless, the mutual coupling impedance of the closely spaced RIS reveals the inefficacy in existing channel estimation schemes, while it is usually ignored in the literature. In this paper, we fill this gap by developing an EM-compliant channel model that integrates mutual coupling explicitly for RIS-assisted THz systems. We evaluate the performance of mutual impedance-induced influence to the accuracy of the root mean square error (RMSE), which is considered as a pivotal …

Performance Enhancement Of Ev Drive System Under Open-Phase Fault Using Reinforcement Learning With Mpc, Ahmed M. Hassan, Mohammed E. Metwally Dr.

Journal of Engineering Research

Improving the operation of electric vehicles (EVs) under fault is a very important subject because it increases their ability to operate in case of an emergency. This paper proposes a fault-tolerant control methodology for an EV drive system under open phase fault (OPF). The 5-ph interior permanent magnet synchronous motor (IPMSM) is employed in the drive system because it has several merits, such as high efficiency and reliability. The proposed technique is based on utilizing a reinforcement learning (RL) control algorithm, based twin-delayed deep deterministic policy gradient (TD3) algorithm, to operate the motor at maximum torque per ampere under OPF. …

An Eulerian-Pfem Approach To Model Transient Capillary Forces On Moving Contact Lines Of Spreading Liquid Drops: Applications In Hydraulic And Fluid Dynamics, Elaf N. Mahrous, Syed Yousufuddin, Muhammad Saleem Professor, Mohammed N. Iqbal, Muhammad T. Bin-Saleem

Journal of Engineering Research

This study addresses the complexities of simulating multiphase flows, particularly the dynamics of droplet behaviour on solid substrates, which are influenced by intricate capillary interactions. Despite advancements in fixed-grid and moving-grid methodologies, there remains a critical gap in accurately modelling transient phenomena and dissipative forces at the solid-liquid interface. We introduce a novel Eulerian-particle finite element method (PFEM) framework that captures the transient capillary forces associated with the movement of contact lines in liquid droplet spreading scenarios. Through a numerical assessment of three established dissipative force models—Jiang’s, Bracke’s, and Seeberg’s we identify Jiang's model as the most effective and stable …

Poly(Pyridinium Salt)S Containing 9,9-Bis(4- Aminophenyl)Fluorene Moieties With Various Organic Counterions Exhibiting Both Lyotropic Liquid-Crystalline And Light-Emitting Properties, Pradip K. Bhowmik, David King, Haesook Han, Andras F. Wacha, Matti Knaapila

Chemistry and Biochemistry Faculty Research

Main-chain conjugated and non-conjugated polyelectrolytes are an important class of materials that have many technological applications ranging from fire-retardant materials to carbon-nanotube composites, nonlinear optical materials, electrochromic materials for smart windows, and optical sensors for biomolecules. Here, we describe a series of poly(pyridinium salt)s-fluorene containing 9,9-bis(4-aminophenyl)fluorene moieties with various organic counterions that were synthesized using ring-transmutation polymerization and metathesis reactions, which are non-conjugated polyelectrolytes. Their chemical structures were characterized by Fourier transform infrared (FTIR), proton (1H) and fluorine 19 (19F) nuclear magnetic resonance (NMR) spectrometers, and elemental analysis. They exhibited polyelectrolytic behavior in dimethyl sulfoxide. Their lyotropic liquid-crystalline phases were …

Grades Are Bugs, Jordan Freitas

Computer Science Faculty Works

This paper argues that grades are bugs in our educational system, undermining desired behaviors and outcomes. Grades were introduced into higher education for purposes directly at odds with the goals of inclusive pedagogy today, as well as the neuroscience of human motivation and learning. Students enter computer science programs from increasingly varied backgrounds and experiences, and face a rapidly evolving landscape of prospective career paths while higher education costs in the United States are ever increasing. Computer science educators have a responsibility to adapt and carefully re-examine typical approaches to all aspects of the learning environments we build and curricula …

Estimating Order Picking Distances Using Machine Learning, Hector J. Carlo, Carlos A. Morel-Figueroa, Victoria Méndez-González, Yamilette Boscio-Sánchez, Alex Demel-Pacheco

International Material Handling Research Colloquium

No abstract provided.

Considerations For Implementing Ai In Warehousing Environments, Irma Adams, Nicolas Iman, Natalie S. Cherbaka

International Material Handling Research Colloquium

No abstract provided.

Machine Learning Approach For The Operation Of Puzzle-Based Storage Systems, Tal Raviv, Yossi Bukchin

International Material Handling Research Colloquium

No abstract provided.

Grid Fragility, Blackouts, And Control Co-Design Solutions, Mario Garcia-Sanz

Faculty Scholarship

The grid is undergoing a large-scale transformation, including a significant reduction of synchronous generators, a high penetration of inverter-based resources and renewables, substantial demand growth, new extra-large loads, aging infrastructure and a concerning vulnerability to contingencies. Some of the recent massive blackouts in Spain/Portugal, Chile and Texas are exposing the fragility of the grid as we know it today. This paper introduces new solutions to stabilize the grid under undesired dynamic interactions and extreme contingencies, with the goal of avoiding cascading failures and blackouts. Using control co-design methodologies, the paper proposes three interdependent categories to improve the reliability and controllability …