Risk Analysis Commons^™

Performance Dynamics Of Activated Carbon-Methanol Pair In Adsorption Refrigeration Systems, Ibrahim J. Mwasubila

Tanzania Journal of Engineering and Technology (TJET)

Adsorption refrigeration systems have shown potential for addressing the adverse effects of traditional compressor-based refrigeration systems. Adsorption refrigeration systems that utilise activated carbon and methanol demonstrate good performance, especially at temperatures below 0 °C. This combination significantly improves the cooling performance of the system, making it a dependable option for freezing applications. Despite having the potential to meet cooling demand and be eco-friendly, the adsorption refrigeration system has several drawbacks that hinder its commercialisation. This paper discusses the properties of the activated carbon methanol pair in the adsorption refrigeration system. The focus is on the desorption temperature, thermal stress, repeatability …

Assessment Of Digital Solutions For Conformity Assessment Of Legally Controlled Measuring Instruments In Tanzania, Faraja Nyoni

Tanzania Journal of Engineering and Technology (TJET)

The advent of state-of-the-art digital technologies since 2011 has led to the digital transformation of legal metrology practices to ensure the trustworthiness of software-controlled measuring instruments globally. Despite the digital transformation in legal metrological practices, the conformity assessment of legally controlled measuring instruments is manually done (i.e., paper-based) in Tanzania. The paper-based conformity assessment of legally controlled measuring instruments is prone to error and lacks efficiency and effectiveness. This study aimed to assess digital solutions for improving conformity assessment through a comprehensive survey conducted across various regions in Tanzania, targeting a stratified sample of 51 respondents from organizations involved in …

Modeling And Estimation Of Co2 Capture By Porous Liquids Through Machine Learning, Farid Amirkhani, Amir Dashti, Hossein Abedsoltan, Amir H. Mohammadi, John L. Zhou, Ali Altaee

Chemical and Biochemical Engineering Faculty Research & Creative Works

Porous liquids (PLs) are newly developed porous materials that combine unique fluidity with permanent porosity, which exhibit promising functionalities. They have shown ability to efficiently absorb greenhouse gases such as carbon dioxide (CO₂). Experimental measurement is one approach to determining the solubility of various greenhouse gases in PLs, which has drawbacks such as being expensive and time-consuming. Hence, simulation models are valuable to predict the solubility of CO₂ in various PLs. This work aims to develop machine learning (ML) modeling methods for accurately estimating CO₂ solubility under varying conditions (e.g. PLs, temperature, pressure). Adaptive Neuro-Fuzzy Inference …

Experimental Characterization And Finite Element Analysis Of The Effects Of Pitting Corrosion On The Mechanical Properties Of Stainless Steel, Duncan Jay Fure, Long Wang

Master's Theses

Many structures do not fail from poor design, but instead from environmental degradation. Corrosion is one mode whose effects can be diminished, but not eliminated, by employing corrosion resistant materials, such as 304 stainless steel, which are still subject to pitting corrosion. Pitting corrosion is a chemical process of the localized removal of material leaving cavities. Despite the prevalence of pitting corrosion, there has been limited testing conducted of the effect of stress during corrosion. This study conducted accelerated controlled corrosion experiments with and without mechanical loading and various corrosion times. Pit morphology of different conditions was analyzed with statistical …

Evaluation Of Damages And Economic Losses In Light-Frame Timber Houses, Mason P. Leonard

Master's Theses

This thesis aims to evaluate the damages and economic losses in light-frame timber houses by designing and constructing a two-story, full-scale, fully equipped, code conforming timber assembly. Specifically, the structure will be analyzed based on how the non-structural components (NSC) like gypsum wallboard, interior doors, windows, and sliding patio doors as well as structural components like light-frame timber shear walls impact the economic losses.

Damage limit states were obtained from the Federal Emergency Management Agency (FEMA) P-58, Performance Assessment of Buildings to extract at what inter-story drift (ISD) ratio each damage limit state was expected to occur at. Fragility and …

Integrating A Stakeholder-Centric Approach Into Dynamic Adaptation Policy Pathways For Equitable Coastal Flood Risk Management In East Boston, Shailee M. Desai

Graduate Doctoral Dissertations

This research aims to illustrate a methodology incorporating diverse stakeholder values in adaptation planning to promote equitable outcomes using a hypothetical case study of the Lower Border Street area in East Boston, using the Dynamic Adaptive Policy Pathways (DAPP) framework for managing coastal flood risk. It offers three significant contributions to the field of adaptation planning: (i) It demonstrates how to integrate a stakeholder-specific assessment within the DAPP framework and illustrates individual impacts to a variety of stakeholders, including high- and low-income residents, commercial actors, government actors, and coastal landowners hoping that the planning process remains transparent and motivates local …

Ultimate Limit State Reliability-Based Approach Life Prediction Of An Existing Frame Structure Under Seismic Hazard In Indonesia, Wira Herucakra, Luh Putri Adnyani

Journal of Materials Exploration and Findings

Life assessment integrated with Structural Integrity Management (SIM) has been implemented in the oil and gas industry for the past decade to maintain the integrity and safety of an in-service structure used to support hydrocarbon exploration, production, and processing activity. Current structural life assessment, as ruled by the American Petroleum Institute (API), uses a fatigue-based approach for offshore structures subjected to wave loading. As the general principle of SIM is not limited to offshore structures, this study offers an alternative life assessment method for onshore structures, especially steel frame structures subjected to earthquake loads. Reliability analysis, combined with the effect …

The Hidden Logic Behind Migration And Success, Elsa Russom

Master's Projects and Capstones

This research paper explores the hidden drivers of financial success among Eritrean migrants navigating uncertainty, displacement, and limited institutional access. Drawing on original survey data collected from diaspora communities across East African host countries, I apply a mixed-methods framework combining ordinal and binary logistic regression, random forest classification, bootstrapping, and Bayesian causal mediation; to identify the structural and cultural variables most predictive of financial stability. The findings reveal that participation in Ekub, a traditional rotating savings association, and engagement in communal support systems are the strongest predictors of financial success, outperforming conventional factors such as age, education, or employment status. …

A Causal Model Of Performance Shaping Factors For Human Reliability Analysis In Manufacturing., Prameet Ranjan Jha

Electronic Theses and Dissertations

Human reliability analysis is a critical component of probabilistic risk assessment, aimed at predicting and mitigating human errors in complex systems. This dissertation develops a novel approach to human reliability analysis in manufacturing by integrating structural equation modeling and Bayesian networks to improve the estimation of human error probabilities. Traditional human reliability assessment methods, such as the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) and the Technique for Human Error Rate Prediction (THERP), provide structured techniques for estimating human error probabilities. However, these methods often fail to capture the complex interdependencies among performance shaping factors (PSFs), limiting their applicability in …

Agent-Based Modeling For Faulty System Analysis, Jayden G. Hamilton

Mechanical Engineering Undergraduate Honors Theses

Numerous approaches exist for computational modeling of complex, dynamic systems. One particular option is the use of agent-based modeling, which simulates the behavior of numerous autonomous agents interacting with each other and with the system at large. Current agent-based modeling research has largely focused on studying the system level behavior of a model, as this is generally the main concern for any real world application. However, the characteristics and behaviors of agents deserves consideration as well. The issue with this area of interest lies in the fact that the agent data cannot be as quickly obtained and analyzed as system …

Integrity Assessment Of Shipping Line Pipelines Using Risk-Based Analysis To Determine Risk And Maintenance Strategies, Ade Ratih Anggraini, Dwi Marta Nurjaya

Journal of Materials Exploration and Findings

Pipeline Shipping Lines X, Y & Z are classified as critical infrastructure, being the only transportation through the crude oil lifting from P and R location to the transfer station in NM Area. To maintain the workflow of the Shipping Line, integrity assessments and risk evaluation are required to ensure the operational and safety. Anomalies were found by analysing inspection, monitoring, and repair data, while the pipelines' future integrity was assessed by calculating the remaining life. Risk-Based Analysis (RBA), which is a modification of Kent Muhlbaeur's method, is employed to conduct the risk assessment using the Probability of Failure (POF) …

Assessment Of H2s-Induced Cracking Susceptibility In Steam Line Pipes And Weld Zones During Geothermal Well Construction, Riene Kaelamanda Pragitta, Yudha Pratesa

Journal of Materials Exploration and Findings

The susceptibility of steam line pipes, especially in the HAZ (heat-affected zone) and weldment areas, to hydrogen sulfide in the geothermal industry is crucial to understand from the early stages, particularly during construction. The combination of tensile stress from residual stresses after welding and metallurgical phase transformation makes the joint areas vulnerable to sulfide stress cracking. This condition becomes even more extreme when the equipment operates during the well stimulation phase. This research assesses the severity of H₂S-induced cracking using NACE MR0175 and ISO 15156-1 standards, focusing on the effects of pH and partial pressure of H₂S (p_{H₂S …}

Toward The Application Of Natural Language Processing In Electronic Health Record Analysis For Taxonomy Development, Latoya Mcdonald

All Dissertations

Electronic health records (EHRs) are pivotal resources for nurse practice because they increase the timeliness and reliability of patient information at the point of care and support access by multiple healthcare providers and the individual patients themselves. However, it is widely recognized that data extraction from EHRs is challenging due to the variability in the language used in clinical care notes and the lack of standardized terminology across healthcare systems. The broad objective of this dissertation is to develop taxonomy-based classification models for nursing care by applying feature engineering approaches to EHRs that include nursing care of ostomy patients following …

A Critical Realist Erp Implementation In Zimbabwean Mining Industry Organisations, Jairos Mukwenha

Tanzania Journal of Engineering and Technology (TJET)

This research uses a critical realist framework to examine the factors influencing the success of enterprise resource planning (ERP) system implementation in Zimbabwean mining industry organisations. From the perspective of critical realism, the mining industry in Zimbabwe faces a complex interplay of opportunities and obstacles while implementing ERP systems. The deployment of ERP in mining firms is critically examined in this paper, emphasising how these systems might improve operational efficiency while considering Zimbabwe's particular socioeconomic circumstances. By exploring underlying structures, mechanisms, and outcomes, the research aims to identify critical challenges and opportunities and develop practical recommendations for improving ERP adoption …

Assessment Of Factors Contributing On Early Rotting Of Chromated Copper Arsenate Treated Utility Power Distribution Wood Poles In Tanzania, Innocent J. Macha

Tanzania Journal of Engineering and Technology (TJET)

The study aimed to assess the factors contributing to the premature decay of Chromated Copper Arsenate (CCA) treated utility power distribution wooden poles in Tanzania. Deteriorated poles samples from various regions in Tanzania were analyzed using handheld X-ray spectrometry to quantify the retention of CCA preservative chemicals. The ages of these poles were estimated based on annual growth rings. The findings indicated that premature failure of CCA treated wooden poles is attributed to an imbalance in the chemical composition of the preservative solution. The study found that CuO retention in most samples ranged between 10-18 kg/m3, significant lower that the …

Developing Predictive Mathematical Model For Optimizing Coating Weight Variation In Galvalume Production: A Case Study Of A Metal Industry, Victoria Mahabi

Tanzania Journal of Engineering and Technology (TJET)

Variations in coating weight for galvanized steel sheets can result in notable differences between batches. Such variations may cause various issues, such as diminished corrosion resistance, lower mechanical strength, and visual defects, which can ultimately drive-up costs, lead to customer dissatisfaction, and pose safety risks. Even with attempts to manage elements like air knife pressure and line speed, coating weight inconsistencies remain challenging. The research focuses on developing a predictive mathematical model designed to optimize variations in coating weight during Galvalume production. The critical parameters influencing coating weight variation were identified and analysed using a systematic literature review, primary data …

A Fuzzy Based Framework For Sustainable Technology Selection In Small-Scale Gold Mining Operations, John M. Kafuku

Tanzania Journal of Engineering and Technology (TJET)

Small-scale gold mining (SSGM) operations in Tanzania has been operating inefficiently due to inadequate mining processing technologies, poor working tools, lack of enough capital, and insufficient electricity. Despite the efforts made by different stakeholders in boosting the sustainability of SSGM yet the sector has not reached the expected goal. This paper proposes a framework for appropriate technology selection to help small scale gold miners in evaluating various gold mineral processing technologies. The framework utilizes the fuzzy logic set theory for technology evaluation and selection. The developed framework for technology selection upon validation provided results that technology adequacy of more than …

Factors Affecting Adoption Of Industry 4.0 Predictive Maintenance By Manufacturing Industries: Tanzania Food And Beverage Manufacturing Industries, Fred E. Peter

Tanzania Journal of Engineering and Technology (TJET)

Industry 4.0 has increasingly become a focal point of scholarly inquiry. Nonetheless, there remains a noticeable lack of comprehensive research on the diverse and systematic factors that influence the adoption of Industry 4.0 Predictive Maintenance (PdM 4.0) in manufacturing sectors within developing regions, particularly in East Africa. This study seeks to bridge this research gap by investigating the key determinants affecting the actual implementation of PdM 4.0 in Tanzania’s food and beverage manufacturing industries. To achieve this objective, a mixed-methods research design was adopted, combining both qualitative and quantitative approaches. Qualitative data were obtained through in-depth interviews with ten industry …

Kennesaw State University Student Managed Investment Fund Sector Sensitivity Analysis, John Kiersznowski, Joe Johnson, Kyler Howell, Geranger Lewis

Senior Design Project For Engineers

The Kennesaw State University Student Managed Investment Fund (SMIF) Sector Sensitivity Analysis focuses on improving the fund’s decision-making and performance through data science. The SMIF is a diversified index fund designed to outperform indices like the S&P 500. This project investigates how macroeconomic variables—such as GDP growth, inflation, interest rates, and commodity prices—impact sector performance. By structuring data, developing a sustainable data pipeline, and leveraging advanced statistical techniques and predictive modeling, our team was able to provide the framework and proof of actionable insights that enhance the fund's ability to manage risks and optimize returns.

From Flames To Change: An Exploration Of Housing, Fire, And Inequity, Helen Underhill, Charles R. Jennings, Brian Meacham, Danielle Antonellis

Publications and Research

Housing and fire safety are deeply connected: inadequate and poorly maintained housing poses heightened fire risk for occupants. An individual or household’s housing situation (including limited or constrained choice) interacts with issues such as affordability, access, location, quality, safety, occupancy levels, tenure type, and resident or immigration status. These dynamics shape vulnerability, and inequity becomes most visible in the event of a fire. The extreme end of this spectrum includes the unhoused, who occupy structures entirely outside of regulatory systems with little or no fire protection.

Quantitative Risk Analysis For Elections, George A. Buras

LSU Master's Theses

This paper examines risk analysis and risk management in the field of election security. The purpose of this paper is not to enumerate risks to election security or explain how they might be mitigated, but rather to understand and improve how we measure and communicate those risks.

First, I contextualize election security risks by establishing what it means for an election to be secure and I give an overview of the types of events that might threaten election security. Then, I explore different methods that we can use to model electoral risks. Existing resources for managing electoral risks use qualitative …

Model-Based Approach To Support Safety Driven Design And Satisfy Mil-Std-882e Requirements With Stpa Coordination: A Case History In Suas Defense Acquisition, Daniel A. Shea

Theses and Dissertations

Increasingly complex defense systems that are routinely overbudget and behind schedule are driving digital engineering initiatives in the defense acquisition industry. MBSE offers a solution to counter this issue but the lack of guidance on how to implement it has led to significant experimentation. One MBSE area of interest is system safety. This research demonstrates how to conduct model-based Systems Theoretic Process Analysis (STPA) to meet the unique system safety process requirements from MIL-STD882E. Based in systems theory, STPA extended for coordination enables a safety-driven design process of complex systems. This research investigated conducting STPA in the SysML-RAAML modeling language …

Sustainability In Forex Trading: A Review In Search Of The Sarsa-Fis Hybrid Method As A Novelty, Joni Fat, Parwadi Moengin, Pudji Astuti, Sally Cahyati

Bulletin of Monetary Economics and Banking

This study employs meta-analysis, rich pictures, timeline analysis, and causal loop diagram to explore the sustainability impacts of the SARSA-FIS hybrid method in forex trading robots. It reviews 56 references (2018-2023), using rich pictures to map AI-driven interactions. Timeline analysis traces AI’s evolution in forex, while causal loop diagram clarifies its role in market dynamics. Responsible algorithms and SRI principles mitigate risks, promoting ethical trading. SARSA-FIS enhances strategies, leveraging AI for sustainable forex practices amidst global uncertainties. The research identifies gaps and positions SARSA-FIS as a novel approach, providing a foundation for advancing AI applications in finance, particularly in forex …

Construction Change Order Data As Inputs For A Programmatic Risk Model, Eric C. Klein

Theses and Dissertations

Hurricane Michael struck Tyndall Air Force Base as a Category 5 storm with 160 mph winds, damaging or destroying 90% of its infrastructure (484 buildings). This devastation prompted the Department of Defense to rebuild Tyndall as the “Installation of the Future,” encompassing 44 Military Construction (MILCON) projects and 260 Facility Restoration, Sustainment, and Modernization (FRSM) projects. Since reconstruction began, over 630 Change Request Forms (CRFs) have been closed, adding $67.8 million in costs and 4,880 construction days. The Air Force Civil Engineer Center's Natural Disaster Recovery (NDR) Division developed a programmatic risk model to predict future costs and delays. However, …

Performance Evaluation Of Free Space Optical Communication In Dar Es Salaam: Impact Of Scintillation And Modulation Schemes, Mustafa H. Mohsini

Tanzania Journal of Engineering and Technology (TJET)

Free space optical communication (FSO) holds significant relevance in the modern communication system as it offers high and unlimited data rates, enhanced security, rapid deployment, and low cost for installation. However, the performance of FSO transmission is greatly affected by harsh atmospheric conditions such as wind, temperature, and humidity, which induce scintillation. With the rapid growth of internet users and Dar es Salaam being a business city in Tanzania, higher and unlimited bandwidth for communication is highly demanded. This study primarily aims to evaluate the performance of FSO transmission in Dar es Salaam, Tanzania, by investigating the impact of atmospheric …

Effectiveness Of Natural Coagulants In Purification Of Industrial Wastewater: A Case Of Cactus Pads And Watermelon Seeds, Neema O. Msuya

Tanzania Journal of Engineering and Technology (TJET)

This study assessed the potential of cactus pads and watermelon seeds as natural coagulants in industrial wastewater treatment. The global characterization of the two coagulants was done by using the Fourier Transform Infrared (FTIR) to determine the specific functional groups and by zeta potential measurements. A full factorial design was used to design the experiment and analyze the effect of three factors: coagulant dosage, settling time and particle size with three levels each and one replicate on the turbidity removal. ANOVA analyses were used to determine the significance of the factors. Results show that the amino and hydroxyl groups in …

Assessment Of Adaptation And Diffusion Of Biogas Technology A Case Study Of Dar Es Salaam City, Tanzania, Doreen L. Tarimo

Tanzania Journal of Engineering and Technology (TJET)

This study investigated the adaptation and diffusion of biogas technology in Dar es Salaam, driven by the increasing need for sustainable energy solutions. The study’s is rooted in addressing urban energy challenges and providing an eco-friendly waste management alternative. Various factors, including socioeconomic variables, technical efficiencies, and community-level acceptability, were examined to assess the technology’s adaptability and diffusion. Data collection methods and techniques included lab analysis using American public health association (APHA) standard methods, interviews, questionnaire administration the data analysis was undertaken using statistical package for the social sciences (SPSS) with a sample size comprising 100 household heads from Mburahati, …

The International Risk Governance Council: Reflections On A 20-Year Experiment In Support Of Improved Risk Governance, M. Granger Morgan, Marie-Valentine Florin, Igor Linkov, Kenneth A. Oye, Arthur C. Petersen, Ortwin Renn, Jonathan B. Wiener, Lan Xue

Faculty Scholarship

The International Risk Governance Council (IRGC) was a nonprofit foundation, based first as an independent, freestanding Swiss foundation in Geneva from 2003 to 2012, and then affiliated with École Polytechnique Fédérale de Lausanne in Lausanne from 2012 to 2023. IRGC's mission was to identify and improve the governance of emerging and systemic risks that have, or could have, impacts on human and environmental health, the economy and society, and overall sustainability. In this paper, we recount IRGC's history, describe its many reports, workshops, and conference activities (including tables referencing the many published products), and provide six brief case histories of …

Machine Learning Modeling For Hydrolysis Recycling Of Pet Waste, Jie Li, Lanjia Pan, Hossein Abedsoltan, Hailong Wang, Taiyang Liu, Xiangzhou Yuan, Yong Sik Ok, Yin Wang

Chemical and Biochemical Engineering Faculty Research & Creative Works

The hydrolysis of polyethylene terephthalate (PET) into terephthalic acid (TPA) can efficiently recycle waste PET, but achieving high conversion efficiency through smart reaction design remains challenging. To develop a robust and accurate machine learning (ML) model for the in-depth understanding and intelligent design of PET hydrolysis, we compiled a new dataset comprising 942 data points and comprehensive information of 44 variables involved in heating type, acid/base catalyst (ABC), organic solvent (OS), co-solvent (CS), phase transfer catalyst (PTC), and operational conditions. The developed Neural Network model demonstrated the best performance in predicting PET conversion, with a testing determination coefficient (R^{2 …}

Fault Tree Analysis For Robust Design, Jonathan Degroff, Gene Jean-Win Hou

Mechanical & Aerospace Engineering Faculty Publications

The objective of this research is to incorporate system failure into a robust design formation and solution process. The system failure referred to here will be built using fault tree analysis (FTA), which will take all lower-level failure events into consideration. Two examples are investigated here. One will directly treat the probabilities of the basis events as design variables, The other will be formulated in five different models: deterministic design optimization, the reliability index-based, the “and” gate-based, the “or” gate-based and the “inhibit” gate-based robust design. Their corresponding optimization solutions will be compared with each other. The post-optimality analysis of …