Engineering Commons^™

Prestressed Steel-Concrete Composite I-Beams With Single And Double Corrugated Web, Mahmoud T. Nawar, Ayman El-Zohairy, Hassan M. Maaly, Mohammed Husain

Faculty Publications

Composite steel girders with concrete have been used for many years and advances in structural and fabrication technology have established their optimization. One of the changes in structural steel I-beams during the past few years has been the availability of web corrugation. The economic design of steel girders normally requires thin webs. Moreover, using externally prestressed tendons as a strengthening technique controls deflections and stresses. However, this strengthening technique causes shear buckling of the steel beams. In this study, the flexural behavior of externally prestressed composite steel-concrete I-beams with a single and double corrugated web was experimentally and numerically investigated. …

Multifunctional Microgel-Based Cream Hydrogels For Postoperative Abdominal Adhesion Prevention, Bo Liu, Yunfan Kong, Olawale A. Alimi, Mitchell Kuss, Huiyin Tu, Wenfeng Hu, Abu Rafay, Kumar Vikas, Wen Shi, Megan Lerner, William L. Berry, Yulong Li, Mark A. Carlson, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

Postoperative abdominal adhesions are a common problem after surgery and can produce serious complications. Current anti-adhesive strategies focus mostly on physical barriers and are unsatisfactory and inefficient. In this study, we designed and synthesized advanced injectable cream-like hydrogels with multiple functionalities, including rapid gelation, self-healing, anti-oxidation, anti-inflammation, and anti-cellular adhesion. The multifunctional hydrogels were facilely formed by the conjugation reaction of epigallocatechin gallate (EGCG) and hyaluronic acid (HA)-based microgels and polyvinyl alcohol (PVA) based on the dynamic boronic ester bond. The physicochemical properties of the hydrogels including anti-oxidative and anti-inflammatory activities were systematically characterized. A mouse cecum-abdominal wall adhesion model …

Separation Axioms In Neutrosophic Topological Spaces, Sudeep Dey, Gautam Chandra Ray

Neutrosophic Systems with Applications

In this article, we first establish some results based on single-valued neutrosophic sets. Next, we define a subspace topology in a neutrosophic topological space and investigate some properties. We then define the neutrosophic T0, T1, T2-spaces and study their various properties, offering adequate examples.

3d Printed Composite Structures For Bone Repair And Drug Delivery Application, Innocent J. Macha

Tanzania Journal of Engineering and Technology (TJET)

Due to the increase in traffic accidents, industrial contingencies, and natural disasters, there is a high demand for bone regeneration biomaterials. Although bone can regenerate and self-repair, it is difficult to do so when the defect area exceeds the critical repair area due to trauma, tumour resection, or congenital diseases. The traditional methods for bone repair are autograft, allograft, and xenograft. However, these methods have flaws and limitations, such as complications in the donor bone area, a limited number of donors, rejection, and infectious diseases. However, in recent years, the use of additive manufacturing technologies in bone tissue engineering has …

Sensible Heat Bean Cooker, Casiana Lwiwa

Tanzania Journal of Engineering and Technology (TJET)

Alternative cooking energy to replace wood fuels is needed in the African context. Liquified Natural Gas (LNG) is a solution but is still based on burning fossil fuel. Electrical cookers can be an alternative as well. However, for off-grid systems this means electrical batteries are required, as the solar electricity from Photovoltaic (PV) panels is intermittent, and as cooking is also to be made after sunset. Heat storage technologies can provide solutions where available energy is stored in the form of heat for cooking when needed. The challenge is then to develop systems which are robust, safe, and technically simple. …

Preparation And Characterization Of Microporous Cellulose Membranes As Potential Pathogen Filters, Peresi M. Bulemo

Tanzania Journal of Engineering and Technology (TJET)

Growth and development in the textile and fashion industry have resulted in the generation of large amounts of industrial pre consumer textile wastes. It is estimated that 10 to 20% of textile fabrics are wasted during garment manufacturing, with most of the wastes being burned or landfilled. Reusing pre-consumer fabric wastes is therefore considered a viable approach to alleviate environmental impacts associated with their disposal. To achieve a higher porosity membrane, pre-consumer cotton fabrics were partially dissolved in a solution of dimethyl acetamide (DMAc) and lithium chloride (LiCl), and the resulting fibre suspension was utilized to prepare a microporous cellulose …

A Mathematical Algorithm Approach For Estimating Water-Based Paint Requirements For A Given Wall, Ismail W. R. Taifa Dr

Tanzania Journal of Engineering and Technology (TJET)

The research aimed to improve the accuracy of estimating water based paint requirements for a given wall using mathematical algorithms. The approach used in this study included a survey and document review to obtain details concerning paint. The study focused on water-based paints, including silk, weather guard, emulsion hi-cover and polyvinyl acetate (PVA) roof paint used in Tanzania’s building and construction industry. Data collected from the field study were analysed systematically. It was observed that there is a high level of familiarity in improving the accuracy of estimation of the required water-based paints, namely silk, weather guard, emulsion hi-cover and …

Dynamic Multi-Dimensional Numerical Transport Study Of Lithium-Ion Battery Active Material Microstructures For Automotive Applications, Joseph S. Lopata, Taylor R. Garrick, Fengkun Wang, Han Zhang, Yangbing Zeng, Sirivatch Shimpalee

Faculty Publications

In support of GM’s traction battery efforts, we derived and implemented a method to describe the electrochemical performance of a battery cell considering the nuances of the electrode microstructure at the anode and the cathode and the corresponding impact on the electrochemical transport in the solid and liquid phases. To assess the capability of the method, we compared model results from the microstructure framework with the commonly used continuum-level porous electrode model, commonly referred to as the pseudo-2-dimensional model, or the Newman Model. The microstructure modeling framework was applied to simulate the electrochemical and transport processes within the battery cell …

Highly Dispersed Pt Nanoparticles Root In Single-Atom Fe Sites In Ldhs Toward Efficient Methanol Oxidation, Qing-Cheng Meng, Lin-Bo Jin, Meng-Ze Ma, Xue-Qing Gao, Ai-Bing Chen, Dao-Jin Zhou, Xiao-Ming Sun

Journal of Electrochemistry

Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell, which has already attracted growing popularities. However, current methanol oxidation electrocatalysts fall far short of expectations and suffer from excessive use of noble metal, mediocre activity, and rapid decay. Here we report the Pt anchored on NiFe-LDHs surface hybrid for stable methanol oxidation in alkaline media. Based on the high intrinsic methanol oxidation activity of Pt nanoparticles, the substrates NiFe-LDHs further enhanced anti-poisoning ability and maintained unaffected stability after 200,000 s cycle test compared to commercial Pt/C catalyst. The …

Exploring Current And Future Research Trends On Safety Climate In Construction Projects, Kamugisha Joseph Kajumulo

Tanzania Journal of Engineering and Technology (TJET)

Clients, consultants, and contractors in the construction industry can benefit from a safety climate by obtaining knowledge of attitudes and perceptions for better safety outcomes. However, the current and future research trends for safety climate in construction projects have not yet been fully examined. In order to solve this problem, a systematic review of previous research findings using a social network approach must be conducted, and future trends for the safety climate in building projects must be identified. Sixty-three peer reviewed articles were gathered to study the literature on safety climate in construction projects. A social network approach was employed …

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 …

Gait And Turning Characteristics From Daily Life Increase Ability To Predict Future Falls In People With Parkinson’S Disease, Vrutangkumar Shah, Adam Jagodinsky, James Mcnames, Multiple Additional Authors

Electrical and Computer Engineering Faculty Publications and Presentations

Objectives: To investigate if digital measures of gait (walking and turning) collected passively over a week of daily activities in people with Parkinson’s disease (PD) increases the discriminative ability to predict future falls compared to fall history alone. Methods: We recruited 34 individuals with PD (17 with history of falls and 17 non-fallers), age: 68 ± 6 years, MDS-UPDRS III ON: 31 ± 9. Participants were classified as fallers (at least one fall) or non-fallers based on self-reported falls in past 6 months. Eighty digital measures of gait were derived from 3 inertial sensors (Opal® V2 System) placed on the …

Knowledge Graph Empowered Machine Learning Pipelines For Improved Efficiency, Reusability, And Explainability, Revathy Venkataramanan, Aalap Tripathy, Martin Foltin, Hong Yung Yip, Annmary Justine, Amit Sheth

Publications

Artificial intelligence (AI) pipelines are complex, heavily parameterized, and expensive to execute in terms of time and computational resources. Consequently, it is onerous to run experiments with all possible parameter combinations to achieve an optimal solution. However, these AI experiments can be optimized by recommending relevant parameters to commence the experiments, reducing search space significantly, which can be fine tuned further. The relevant parameters can be identified by observing the metadata of pipelines executed in the past, and the relevant pipeline with relevant parameters can be recommended to the user. Currently, there are various metadata frameworks that automatically record the …

Cellulose-Keratin Supramolecular Composite: Conformation By Combined Fourier Transform Spectroscopy And Partial Least Square Regression Coefficient, Ngesa Ezekiel Mushi Dr

Tanzania Journal of Engineering and Technology (TJET)

Keratin and cellulose are important nano components with excellent mechanical and biological properties. However, the preparation route through dissolution in organic solvents to make manmade materials is challenging because of their intensive bonding interaction characteristics. Structural modification of the natural attributes is difficult to maintain after polymer regeneration. A new technique by a green route was devised to dissolve keratin from wool, hair, and feather with cellulose in situ using 1-Butyl-3-methylimidazolium chloride [BMIm] + Cl- ionic liquid as a solvent. The mixture of keratin and cellulose homogeneously and synergistically resulted in a supramolecular composite film through non-derivatized mechanochemical interactions. The …

Development Of Solar Pv Systems For Mini-Grid Applications In Tanzania, Seleman Mayanjo

Tanzania Journal of Engineering and Technology (TJET)

Access to electricity offers great benefits to development through the provision of reliable and efficient energy sources in the country. Majority of the population living in the remote and rural areas of developing countries mostly sub-Saharan Africa are not supplied with electricity. Although the governments through their electricity companies put their effort to extends the grid distribution networks to remote and rural areas still the coverage were not sufficiently enough due to growing demands for safe and reliable electricity. However, solar as a source of energy remains the least utilized energy source in many countries including Tanzania. Solar Photovoltaic (PV) …

Comparison Of On-Line Partial Discharge Detection Techniques For High Voltage Power Cable Joints And Terminations, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

Cable joints and terminations play a vital role in providing dependable electrical connection, mechanical support and physical safeguard. These provide electrical stress control to shielded power cables. Despite their usefulness, they suffer from partial discharges (PD) because of enhanced voltage stress, moisture ingress and poor workmanship (during installation). Therefore, it is necessary to undertake on-line PD detection to determine their state. Some of these techniques are capacitive coupler (CC); acoustic emission (AE); and high frequency current transducer (HFCT). This article presents a literature review of these techniques based on the cost, availability, and applicability. The comparative analysis is also provided …

Optimal Energy Management For Off-Grid Hybrid Renewable Energy Systems, Owdean M. Suwi

Tanzania Journal of Engineering and Technology (TJET)

A photovoltaic (PV)/wind/battery/Generator-Set hybrid power system's energy dispatch is discussed in this research, along with the ideal solution. The optimization model enables the hybrid power system's generating devices to share power appropriately. The main goals are to minimize fuel consumption and costs and maximize the usage of Renewable Energy Sources (RES). The proposed simulation plan succeeds in lowering fuel costs because the diesel generator only kicks on at night and in the early morning when the energy from RES is insufficient to supply the load. The load is supplied with power, and the battery is charged throughout the day, when …

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. …

Preface To Special Issue On Electrocatalysis And Electrosynthesis, Fang-Yi Cheng, Shuang-Yin Wang, Tian-Hua Zhou

Journal of Electrochemistry

No abstract provided.

Advances And Challenges On Cathode Catalysts For Lithium-Oxygen Batteries, Bo Wen, Zhuo Zhu, Fu-Jun Li

Journal of Electrochemistry

Aprotic lithium-oxygen batteries (LOBs) with high theoretical energy density have received considerable attention over the past years. However, the oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) at cathodes suffer from slow kinetics for large overvoltages in LOBs. Significant advances on catalysts have been achieved to accelerate cathode kinetics, but understanding on the formation/decomposition processes of Li₂O₂ is limited. Herein, this review highlights the fundamental understanding of the correlation between catalysts and formation/decomposition of Li₂O₂. Various types of cathode catalysts are discussed to reveal the mechanism of formation/decomposition of Li₂O₂, …

Design And Performance Analysis Of Dry Gas Fishbone Wells For Lower Carbon Footprint, Habib Ouadi, Aimen Laalam, Amjed Hassan, Abderraouf Chemmakh, Vamegh Rasouli, Mohamed Mahmoud

Petroleum Engineering Student Publications

Multilateral well drilling technology has recently assisted the drilling industry in improving borehole contact area and reducing operation time, while maintaining a competitive cost. The most advanced multilateral well drilling method is Fishbone drilling (FbD). This method has been utilized in several hydrocarbon fields worldwide, resulting in high recovery enhancement and reduced carbon emissions from drilling. FbD involves drilling several branches from laterals and can be considered as an alternative method to hydraulic fracturing to increase the stimulated reservoir volume. However, the expected productivity of applying a Fishbone well from one field to another can vary due to various challenges …

Calculations Of Adsorption-Dependent Refractive Indices Of Metal-Organic Frameworks For Gas Sensing Applications, Nahideh Salehifar, Peter Holtmann, Abhishek Prakash Hungund, Homayoon Soleimani Dinani, Rex E. Gerald, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Detection of Volatile Organic Compounds (VOCs) is One of the Most Challenging Tasks in Modelling Breath Analyzers Because of their Low Concentrations (Parts-Per-Billion (Ppb) to Parts-Per-Million (Ppm)) in Breath and the High Humidity Levels in Exhaled Breaths. the Refractive Index is One of the Crucial Optical Properties of Metal-Organic Frameworks (MOFs), Which is Changeable Via the Variation of Gas Species and Concentrations that Can Be Utilized as Gas Detectors. Herein, for the First Time, We Used Lorentz–Lorentz, Maxwell–Ga, and Bruggeman Effective Medium Approximation (EMA) Equations to Compute the Percentage Change in the Index of Refraction (∆n%) of ZIF-7, ZIF-8, ZIF-90, …

Split And Join: An Efficient Approach For Simulating Stapled Intestinal Anastomosis In Virtual Reality, Di Qi, Suvranu De

Engineering Faculty Articles and Research

Colorectal cancer is a life-threatening disease. It is the second leading cause of cancer-related deaths in the United States. Stapled anastomosis is a rapid treatment for colorectal cancer and other intestinal diseases and has become an integral part of routine surgical practice. However, to the best of our knowledge, there is no existing work simulating intestinal anastomosis that often involves sophisticated soft tissue manipulations such as cutting and stitching. In this paper, for the first time, we propose a novel split and join approach to simulate a side-to-side stapled intestinal anastomosis in virtual reality. We mimic the intestine model using …

Investigation Of Electrically Isolated Capacitive Sensing Skins On Concrete To Reduce Structure/Sensor Capacitive Coupling, Emmanuel Ogunniyi, Alexander Vareen, Austin Downey, Simon Laflamme, Jian Li, Caroline Bennett, William Collins, Hongki Jo, Alexander Henderson, Paul Ziehl

Faculty Publications

Damage to bridges can result in partial or complete structural failures, with fatal consequences. Cracks develop in concrete infrastructure from fatigue loading, vibrations, corrosion, or unforeseen structural displacement. Effective long-term monitoring of civil infrastructure can reduce the risk of structural failures and potentially reduce the cost and frequency of inspections. However, deploying structural health monitoring technologies for crack detection on bridges is expensive, especially long-term, due to the density of sensors required to detect, localize, and quantify cracks. Previous research on soft elastomeric capacitors (SECs) has shown their viability for low-cost monitoring of cracks in transportation infrastructure. However, when deployed …

On Refinements To Qmfd Based Chirp Parameter Estimation, Balu Santhanam, Thalanayar Santhanam

Electrical & Computer Engineering Technical Reports

Commuting matrix methods furnish a full basis of orthog- onal eigenvectors for the discrete Fourier transform or its centered version needed for computing the discrete fractional Fourier transform and multicomponent chirp signal analysis. However, these approaches suffer from ill-conditioning issues at higher matrix sizes, and require a computationally expensive eigenvalue decomposition.

In this paper, ill-conditioning issues associated with the QMFD approach developed previously by the authors are addressed via diagonal modification. Further symmetries of the eigenvectors are used to reduce the size of the underlying eigenvalue problem. These modifications are then incorporated into the real-arithmetic implementation of the QMFD approach …

Comparison Of Oxygen Supplementation In Very Preterm Infants: Variations Of Oxygen Saturation Features And Their Application To Hypoxemic Episode Based Risk Stratification, Pravitha Ramanand, Premananda Indic, Colm P. Travers, Namasivayam Ambalavanan

Electrical Engineering Faculty Publications and Presentations

Background: Oxygen supplementation is commonly used to maintain oxygen saturation (SpO2) levels in preterm infants within target ranges to reduce intermittent hypoxemic (IH) events, which are associated with short- and long-term morbidities. There is not much information available about differences in oxygenation patterns in infants undergoing such supplementations nor their relation to observed IH events. This study aimed to describe oxygenation characteristics during two types of supplementation by studying SpO2 signal features and assess their performance in hypoxemia risk screening during NICU monitoring. Subjects and methods: SpO2 data from 25 infants with gestational age  0.80, F1 score > 0.60 and specificity …

Creativity, Craftsmanship, And Connection: Large-Format Sculpture Design, Jacqueline L. Puga, Gordon Hoople

The Transdisciplinary STEAM+ Journal

Artistry is a concept that is not usually explored in engineering yet is an invaluable skill that touches everything from product design to systems thinking. This past summer I developed conceptual designs for a large format sculpture that required connecting engineering knowledge with artistic vision. The initial phase required constant inspiration and creativity. The first step was to look at previous sculptures showcased throughout the world, such as at venues like “Burning Man,” to understand the possibilities or limitations of the space provided. Sketching varied and numerous ideas was essential in our design process. Next, we took our favorite ideas …

Collaboration Between Science And Art Through A Special International Symposium For Ecosystem Health And Sustainability, Changwoo Ahn Dr.

The Transdisciplinary STEAM+ Journal

The collaborations between ecosystem restoration and art practices was epitomized by the eco-artist Jackie Brookner who said: “it is not a matter of the scientists providing the hard-core research and artists the soft outreach; rather, the dynamics engendered in the space between disciplines is full of information necessary to solve complex problems at the systemic level”. This paper reviews and summaries the goals, activities, and lessons learned from a special symposium, which was held at the 12^th INTECOL (International Congress of Ecology) conference in Beijing, China, August 21 through 25, 2017, where about 3000 people attended from 70 countries. …

Steam And Environmental Justice In An Interdisciplinary Context, Paula Farca, Alina Handorean, Jürgen Brune

The Transdisciplinary STEAM+ Journal

This course proposes an interdisciplinary perspective, envisions unique synergies between environmental justice concepts and STEAM projects on mining, and aims to solidify a foundation based on justice, equity, equality, and empathy for STEM students and faculty. Our (S)TEAM made of professors in three academic departments underscores interdisciplinary and diversity connections through an interdisciplinary team-taught course, units on environmental justice related to mining, teaching of literary texts, and STEAM projects. We also involved faculty, alumni, and our campus and city community through STEAM exhibits.

Gömböc The Great, Indigo M. Strickert, Lori E. Bradford

The Transdisciplinary STEAM+ Journal

A sonnet written about the mathematics behind the self-righting shape of some tortoise shells.