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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Assessing the potential risk of failing to maintain water supply in the Rand Water area / Londani Phillip Lithole

Lithole, Londani Phillip January 2015 (has links)
The research study focused on assessing the potential risk of failing to maintain water supply in the Rand Water area. The study analysed all factors and areas that contributes to water supply in the Rand Water area; this included municipalities supplied by Rand Water, the Department of Water Affairs and other factors that directly affect Rand Water supply such as population growth, increased urbanisation and acid mine drainage. The objectives of the study were: (a) is to determine the potential risk of failing to maintain supply in the Rand Water supply area, in other words, the likeliness of water not being supplied adequately to customers. (b) generate timely and credible information to determine the understanding, awareness, and acknowledgement by the sampled management group of the existence of the potential water supply risk in the Rand Water supply area. This will be done through a quantitative study. The research study approach that was utilized was a quantitative methodology; this approach included the distribution of questionnaires to all relevant stakeholders in the Rand Water supply area. To address the problems that are highlighted in the problem statement and achieve the objectives of the study these answered questionnaires were then sent to a Statistical consultant at North-West University‟s Potchefstroom Campus, to be analysed using an SPSS Version 21 statistical program. The questionnaires were divided into the three big municipal customers, these municipalities combined takes a total of 74.35% of Rand Water supply; these are Johannesburg Water which is part of the City of Johannesburg Metropolitan Municipality, Ekurhuleni Metropolitan Municipality, Tshwane Metropolitan Municipality and other small municipalities and the Department of Water Affairs‟ officials. Many previous studies also were assessed to be able to help this study establish the seriousness of the water challenge, the amount of work that has already been done, factors contributing to the problem and finally, measures that can be put in place to address the problem. The results that were obtained for this study provided many relationships between this study‟s selected variables and also highlighted the need to put certain strategies in place to be able to control the growing demand for water in the Rand Water system. The name of the Department of Water Affairs has changed many times over the year. It used to be called DWAF (Department of Water Affairs and Forestry, then DWEA (Department of Water and Environmental Affairs, then DWA (Department of Water Affairs) and it has recently been changed to DWS (Department of Water and Sanitation. For the purposes of this study this department will be called DWA (The Department of Water Affairs) The results were very relevant as most of the relationships were found between variables that are practically supposed to be related in order for the problem to be dealt with fruitfully. From these results it could be concluded that the risk of failing to maintain water supply in the Rand Water supply area does exist, if certain factors were allowed to trend the way they‟ve been trending without measures in place to counteract them. It could also be concluded that certain measures have been initiated to deal with the problem; this included water demand management. Results indicated that collective efforts from all stakeholders in the Rand Water supply area will be crucial in addressing the water supply challenge and avoid future failure to supply. To close the gap between previous research studies and this research study recommendations were made. Areas of future research were also highlighted; these are areas that can add value in providing valued information to help the challenge of water shortage in the Rand Water supply area. This area of future research studies will also be crucial in identifying other external factors that were not highlighted in the study but contribute to the problem. This area of future research studies will also help when implementing turnaround strategies to avoid the risk of failing to maintain supply in the Rand Water area as it will be able to highlight a different strategy that deals with the problem holistically. / MBA, North-West University, Potchefstroom Campus, 2015
2

Assessing the potential risk of failing to maintain water supply in the Rand Water area / Londani Phillip Lithole

Lithole, Londani Phillip January 2015 (has links)
The research study focused on assessing the potential risk of failing to maintain water supply in the Rand Water area. The study analysed all factors and areas that contributes to water supply in the Rand Water area; this included municipalities supplied by Rand Water, the Department of Water Affairs and other factors that directly affect Rand Water supply such as population growth, increased urbanisation and acid mine drainage. The objectives of the study were: (a) is to determine the potential risk of failing to maintain supply in the Rand Water supply area, in other words, the likeliness of water not being supplied adequately to customers. (b) generate timely and credible information to determine the understanding, awareness, and acknowledgement by the sampled management group of the existence of the potential water supply risk in the Rand Water supply area. This will be done through a quantitative study. The research study approach that was utilized was a quantitative methodology; this approach included the distribution of questionnaires to all relevant stakeholders in the Rand Water supply area. To address the problems that are highlighted in the problem statement and achieve the objectives of the study these answered questionnaires were then sent to a Statistical consultant at North-West University‟s Potchefstroom Campus, to be analysed using an SPSS Version 21 statistical program. The questionnaires were divided into the three big municipal customers, these municipalities combined takes a total of 74.35% of Rand Water supply; these are Johannesburg Water which is part of the City of Johannesburg Metropolitan Municipality, Ekurhuleni Metropolitan Municipality, Tshwane Metropolitan Municipality and other small municipalities and the Department of Water Affairs‟ officials. Many previous studies also were assessed to be able to help this study establish the seriousness of the water challenge, the amount of work that has already been done, factors contributing to the problem and finally, measures that can be put in place to address the problem. The results that were obtained for this study provided many relationships between this study‟s selected variables and also highlighted the need to put certain strategies in place to be able to control the growing demand for water in the Rand Water system. The name of the Department of Water Affairs has changed many times over the year. It used to be called DWAF (Department of Water Affairs and Forestry, then DWEA (Department of Water and Environmental Affairs, then DWA (Department of Water Affairs) and it has recently been changed to DWS (Department of Water and Sanitation. For the purposes of this study this department will be called DWA (The Department of Water Affairs) The results were very relevant as most of the relationships were found between variables that are practically supposed to be related in order for the problem to be dealt with fruitfully. From these results it could be concluded that the risk of failing to maintain water supply in the Rand Water supply area does exist, if certain factors were allowed to trend the way they‟ve been trending without measures in place to counteract them. It could also be concluded that certain measures have been initiated to deal with the problem; this included water demand management. Results indicated that collective efforts from all stakeholders in the Rand Water supply area will be crucial in addressing the water supply challenge and avoid future failure to supply. To close the gap between previous research studies and this research study recommendations were made. Areas of future research were also highlighted; these are areas that can add value in providing valued information to help the challenge of water shortage in the Rand Water supply area. This area of future research studies will also be crucial in identifying other external factors that were not highlighted in the study but contribute to the problem. This area of future research studies will also help when implementing turnaround strategies to avoid the risk of failing to maintain supply in the Rand Water area as it will be able to highlight a different strategy that deals with the problem holistically. / MBA, North-West University, Potchefstroom Campus, 2015
3

Banking instability : causes and remedies

Tajik, Mohammad January 2015 (has links)
The recent U.S. subprime mortgage crisis rapidly spread throughout the world and put the global financial system under extraordinary pressure. The main implication of the recent crisis is that complex banking regulations failed to adequately identify and limit riskiness of banking systems at both domestic and international levels. In spite of a large empirical literature on the causes and remedies of the recent crisis, there remains substantial uncertainty on (i) how risk measuring models performed during crisis, (ii) how systematic factors such as house prices affected the financial system, and (iii) how effectively government policy responses resolved the financial crisis. This thesis seeks to narrow this gap in the literature by offering three empirical essays. The first essay investigates the performance of alternative parametric VaR models in forecasting riskiness of international equity portfolios. Notably, alternative univariate VaR models are compared to multivariate conditional volatility models with special focus given to conditional correlation models. Conditional correlation models include the constant conditional correlation (CCC), dynamic conditional correlation (DCC), and asymmetric DCC (ADCC) models. Various criteria are then applied for backtesting VaR models and to evaluate their one-day-ahead forecasting ability in a wide range of countries and during different global financial conditions. It is found that most VaR models have satisfactory performance with small number of violations during pre-crisis period. However, the number of violations, mean deviation of violations, and maximum deviation of violations dramatically increase during crisis period. Furthermore, portfolio models incur lower number of violations compared to univariate models while DCC and ADCC models perform better than CCC models during crisis period. From risk management perspective, most single index models fail to pass Basel criteria for internal VaR models during crisis period, whereas empirical evidence on the choice between CCC, DCC, and ADCC models is mixed. The recent crisis also raised serious concerns about factors that can systematically destabilise the whole banking system. In particular, the collapse of house prices in the United States triggered the recent subprime mortgage crisis, which was associated with a sharp increase in the number of nonperforming loans and bank failures. This in turn demonstrates the key role that house prices play in systematically undermining the whole banking system. The second essay investigates the determinants of nonperforming loans (NPL) with a special focus on house price fluctuations as a key systematic factor. Using a panel of U.S. banking institutions from 1999 to 2012, the analysis is carried out across different loan categories, different types of banks, and different bank size. It is found that house price fluctuations have a significant impact on the evolution of nonperforming loans, while the magnitude of their impact varies across loan categories, institution types, and between large and small banks. Also, the impact of house price fluctuations on nonperforming loans is more pronounced during crisis period. The last essay of this thesis investigates the effectiveness of the U.S. government strategy to combat the crisis. As a comprehensive response to the recent financial crisis, the US government created the Troubled Asset Relief Program (TARP). The Capital Purchase Program (CPP) was launched as an initial program under the TARP. The CPP was designed to purchase preferred stocks or equity warrants from viable financial institutions. Using a large panel of the U.S. commercial banks over the period 2007Q1 to 2012Q4, survival analysis is used to investigate the impact of TARP funds on the likelihood of survival in the recipient banks. It is found that larger recipient banks are more likely to avoid regulatory closure, while receiving capital assistance does not effectively help banks to avoid technical failure. This implies that governmental capital assistance serves larger banks much better than their smaller counterparts. In addition, TARP recipients are more likely to be acquired, regardless of their size and financial health. In summary, the empirical findings reveal that capital infusions do not enhance the survival likelihood of the recipient banking institutions.
4

The personality of company directors as a behavioural risk contributor in the corporate governance process : regulatory intervention as a risk management mechanism

Okoye, Ngozi January 2012 (has links)
This thesis examines behavioural risks in corporate governance, and seeks to ascertain what constitutes behaviour. It finds upon an examination and analysis of literature that “personality” and “situations” are elements which contribute to behaviour. Consideration of risk management mechanisms in corporate governance indicates that the personality aspect of behavioural risks has remained largely unidentified. The thesis then focuses on the personality of company directors as a significant contributory factor to their behaviour, and therefore also constituting potential behavioural risks in relation to corporate governance. A question then arises as to how behavioural risks and personality risks in particular have been managed in corporate governance. Taking cognisance of the processes involved in risk management, it is found that personality risks have not been identified by any corporate governance mechanisms, and which means, therefore, that these risks have not been managed effectively under any of the existing corporate governance mechanisms, such as the Turnbull Guidance, UK Corporate Governance Code, UK Companies Act, and EU Company Law Directives.Considering the negative economic and social impact of corporate failures in relation to public listed companies, and the justification for the State to intervene in order to safeguard society from the occurrence and consequences of these failures, this thesis suggests a hybrid regulatory model as an approach to managing personality risks in corporate governance. Building upon relevant corporate and regulatory theories; and incorporating current realities as they relate to the regulation of companies, the thesis proposes a model with suggested provisions which are aimed at contributing to an effective outcome as regards personality risk management. The fundamental requirements of an effective risk management process are discussed and engaged with in the process of developing a conceptual framework for personality risk management from which the approach and provisions in the suggested model are drawn.
5

A Risk Analysis Model for the Maintenance and Rehabilitation of Pipes in a Water Distribution System: A Statistical Approach

Cortez, Hernan 01 June 2015 (has links) (PDF)
ABSTRACT The network of pipes in potable water distribution systems (WDS) are comprised of thousands of pipes made of various materials including PVC, concrete, cast iron, and steel, among several others. The pipes are subjected to internal and external conditions that lead to their failure. Stress conditions include, but are not limited to internal pressures, traffic loading, and corrosion. The deterioration of a pipe decreases its mechanical strength which results in an increase of its probability of failure. Failures lead to loss of service which translates to loss of money due to the cost of repairs and buildup of traffic caused by street closures. The focus of this study is the pipe network underneath cities that make it possible for communities to have access to potable water. The objective of this analysis is to evaluate the physical conditions of each pipe in a water distribution system in order to assess its probability of failure and ultimately calculate the risk associated with each pipe in the case that it were to fail. This model focuses only on the pipes of the WDS and does not take into consideration fittings, pumps, and other network components. This model assesses pipe age, material, diameter, internal pressure, traffic loading (industrial or residential), and length to determine the probability of failure. It then utilizes several economic factors such as material cost, customer criticality, demand, traffic impact, and land use to calculate the risk associated with each pipe. The risk associated with each pipe can then be used as a ranking system to identify the most vulnerable pipes, those with the highest economic impact upon failure. Identifying the pipes with the highest risk allows municipalities to better allocate funds for maintenance or replacement of pipes. It highlights the most critical pipes within a network of thousands. In order to check its functionality, this model applied to the WDS of the City of Arroyo Grande, California. Information on the City’s distribution system was analyzed using Bentley’s WaterCAD, ESRI’s ArcGIS, MathWorks’ MATLAB and Microsoft’s Excel software to perform the analysis. The risk analysis model provided 3 pipes within the distribution system made of cast iron as having a high probability of failure and a critical level of risk. A critical level of risk is defined as falling within the highest range of risk within this study. Considering that only 3 pipe segments were highlighted as having a Critical Risk, 4 as High Risk, and 6 as Medium Risk, in a system of 3572 pipes indicates that the model functions properly. This model was compared to a method developed by Jan C. Devera in his thesis “Risk Assessment Model for Pipe Rehabilitation and Replacement in a Water Distribution System” (2013), which was also applied to the City of Arroyo Grande’s distribution system. Results provided by this analysis prove that both models are functional due to similar results. The current study utilizes the concepts of random variables and conditional assessment to run various Monte Carlo Simulations as the means of calculating the probability of failure of a pipe. Mr. Devera’s model utilizes simplistic approach that does not involve intensive calculations, but results for both models turned out to be similar when looking at the Arroyo Grande distribution system. This risk assessment model demonstrates that a risk assessment model can provide a framework to prioritize pipes based on risk. The approach can help create a schedule for a city’s pipe distribution network for maintenance and repair. It is important to note that it is not a predictive model. This study may be employed to better allocate funds for the rehabilitation and replacement of a city’s existing pipe network to promote optimal operating conditions and service to the public.
6

Optimising Turnaround Maintenance (TAM) Scheduling of Gas plants in Libya

El Werfalli, Abdelnaser A.K. January 2018 (has links)
Gas plants consist of several pieces of both critical static and rotating equipment, which operate continuously under severe operating conditions. These pieces of equipment are permanently subjected to be inspected and maintained during total shutdown of plant facilities to execute Turnaround Maintenance (TAM) event. The TAM is the largest maintenance activities used in most oil and gas companies in terms of both cost and time. Oil and gas companies have suffered losses in the production and enormity in the TAM cost due to duration and interval of TAM which have randomly estimated without taking the size and age of plants into account. Sirte Oil Company (SOC) was a good example and used as a reference point for other gas plants to achieve the aim of this thesis associated with optimising TAM scheduling for gas plants (decreasing duration and increasing interval of TAM) by implementing the TAM model. The contribution of this research is in developing the TAM model, consisting of four stages, which is broken down into four main stages: First stage; removing Non-critical pieces of Equipment (NEs) from the Scope of Work (SoW) of TAM to proactive maintenance strategies. Second stage; selecting Critical Static pieces of Equipment (CSEs) that constitute the highest risk based on Risk-Based Inspection (RBI). Third stage; selecting Critical Rotating pieces of Equipment (CREs) that constitute the highest risk based on Risk-Based Failure (RBF). Fourth stage; defining the optimum duration and interval of TAM based on Failure Distributions (FDs). Consequently, the TAM model developed in this study provides a novelty in the TAM event and decision making process. This is basically about optimisation of TAM scheduling in the medium and long-term, characterized by decreasing duration and increasing interval of TAM based on both CSEs and CREs to achieve the TAM model results. The result is the reduction in TAM cost and production losses, and the improvement in reliability and availability requirements of gas plants according to the residual life of critical equipment and operating conditions. To ensure reliability and consistency of the TAM model, it was validated with three Libya-plants SOC and data from three published case studies. The results from the validation of the TAM model are consistent with the real duration and interval of TAM in most plants SOC. The research concludes that the developed TAM model is a reliable and applicable tool to assist decision-makers in the estimation of TAM scheduling for any a processing plant.
7

A Comparison of Risk Assessment Models for Pipe Replacement and Rehabilitation in a Water Distribution System

Nemeth, Lyle John 01 June 2016 (has links)
A water distribution system is composed of thousands of pipes of varying materials, sizes, and ages. These pipes experience physical, environmental, and operational factors that cause deterioration and ultimately lead to their failure. Pipe deterioration results in increased break rates, decreased hydraulic capacity, and adverse effects on water quality. Pipe failures result in economic losses to the governing municipality due to loss of service, cost of pipe repair/replacement, damage incurred due to flooding, and disruptions to normal business operations. Inspecting the entire water distribution system for deterioration is difficult and economically unfeasible; therefore, it benefits municipalities to utilize a risk assessment model to identify the most critical components of the system and develop an effective rehabilitation or replacement schedule. This study compared two risk assessment models, a statistically complex model and a simplified model. Based on the physical, environmental, and operational conditions of each pipe, these models estimate the probability of failure, quantify the consequences of a failure, and ultimately determine the risk of failure of a pipe. The models differ in their calculation of the probability of failure. The statistically complex model calculates the probability of failure based on pipe material, diameter, length, internal pressure, land use, and age. The simplified model only accounts for pipe material and age in its calculation of probability of failure. Consequences of a pipe failure include the cost to replace the pipe, service interruption, traffic impact, and customer criticality impact. The risk of failure of a pipe is determined as the combination of the probability of failure and the consequences of a failure. Based on the risk of failure of each pipe within the water distribution system, a ranking system is developed, which identifies the pipes with the most critical risk. Utilization of this ranking system allows municipalities to effectively allocate funds for rehabilitation. This study analyzed the 628-pipe water distribution system in the City of Buellton, California. Four analyses were completed on the system, an original analysis and three sensitivity analyses. The sensitivity analyses displayed the worst-case scenarios for the water distribution system for each assumed variable. The results of the four analyses are provided below. Risk Analysis Simplified Model Complex Model Original Analysis All pipes were low risk All pipes were low risk Sensitivity Analysis: Older Pipe Age Identified 2 medium risk pipes Identified 2 medium risk pipes Sensitivity Analysis: Lower Anticipated Service Life Identified 2 medium risk pipes Identified 9 high risk pipes and 283 medium risk pipes Sensitivity Analysis: Older Pipe Age and Lower Anticipated Service Life Identified 1 high risk pipe and 330 medium risk pipes Identified 111 critical risk pipes, 149 high risk pipes, and 137 medium risk pipes Although the results appeared similar in the original analysis, it was clear that the statistically complex model incorporated additional deterioration factors into its analysis, which increased the probability of failure and ultimately the risk of failure of each pipe. With sufficient data, it is recommended that the complex model be utilized to more accurately account for the factors that cause pipe failures. This study proved that a risk assessment model is effective in identifying critical components and developing a pipe maintenance schedule. Utilization of a risk assessment model will allow municipalities to effectively allocate funds and optimize their water distribution system. Keywords: Water Distribution System/Network, Risk of Failure, Monte Carlo Simulation, Normal Random Variable, Conditional Assessment, Sensitivity Analysis.
8

Recherches sur les coûts et les bénéfices de la nouvelle régulation bancaire. Applications au cas européen / Essays on the costs and the benefits of the new regulatory framework : An application to European banks

Toader, Oana 05 July 2016 (has links)
L’arbitrage entre la stabilité et l’efficience des systèmes bancaires a toujours été au coeur de la définition desdispositifs de régulation bancaire. Cette thèse analyse comment cet arbitrage a été conçu et dans quelle mesure ila permis de concilier les deux types d’objectifs, c’est-à-dire les coûts et les bénéfices de la nouvelle réglementation.Nous évaluons, dans une première partie, l’impact des exigences renforcées en fonds propres et en liquidité sur lecoût du capital et sur l’activité bancaire. Les résultats empiriques montrent de manière générale que les coûts desnormes imposées par Bâle III sont relativement faibles et ont un impact limité sur l’activité de crédit. Nous mettonsen évidence un effet différencié selon les différentes catégories de banques, selon leur taille, importance systémique oubusiness model. Un autre constat tiré de cette étude concerne les anomalies dans la tarification du risque, généréespar l’existence des garanties implicites. C’est pourquoi, la seconde partie est consacrée à leur analyse approfondie etaux mesures mises en place pour éliminer le fameux problème de too big to fail. Même si des mesures ambitieusesont été adoptées par les autorités de régulation, les distorsions liées à l’activité des banques TBTF persistent. On envient à s’interroger, dans le cadre de la dernière partie, sur l’amélioration de la stabilité des institutions. Les résultatsmontrent que la mise en place des bonnes incitations, notamment grâce à des standards prudentiels adéquats, pourraits’avérer comme une solution efficiente pour réduire les risques financiers (probabilité de défaut, sensibilité au risquesystémique, perte en cas de scénario adverse). Ces différentes questions sont analysées pour les banques européennes.La démarche retenue est principalement empirique et les aspects microéconomiques ont été privilégiés. / The arbitrage between financial stability and the efficiency of banking systems has always been a key issue indefining the prudential regulation. This thesis analyses how this arbitrage is conceived and the extent to which itallows to reconcile the two objectives, namely the cost and the benefits of the new regulatory framework. We firstfocus on the impact of the new capital and liquidity requirements on the cost of capital and on banking activities. Ourfindings indicate that, globally, the cost of the recent reform is relatively low and does not have a significant impacton lending. We also emphasize a differentiated effect according to banks’ size, systemic importance and businessmodel. The existence of various distortions, affecting the pricing of risk, motivates the second part of the thesis, whichis dedicated to the analysis of implicit guarantees. We also assess the impact of resolution regimes and practices inending the too big to fail anomaly. Although ambitious measures have been undertaken, there is still a way to go toeliminate these distortions. In the third part, we examine the contribution of solvency and liquidity requirements tostrengthen the resilience of banks. The results indicate that setting up good incentives, through adequate prudentialstandards, could efficiently reduce financial risks (default probability, systemic risk, capital shortfall in case of adversescenario). The approach adopted in this thesis focuses on microeconomic aspects and is based on empirical studiesapplied to a sample of European banks.
9

Analýza vybraných genetických markerů u pacientů po transplantaci srdce / Analysis of selected genetic markers in patients after heart transplant

Petříková, Nikola January 2016 (has links)
Heart transplantation is performed in patients with end-stage heart failure, in whom all other methods of treatment failed. The most common causes of end-stage heart failure are dilated cardiomyopathy and coronary artery disease. The destiny of these patients is highly variable. Prediction of long term survival in patients after heart transplantation is not satisfactory and up to now has not been found reliable marker. Most of the patients die after heart transplantation due to cardiovascular disease. This thesis is focused on molecular genetics and statistical analysis of four single nucleotide polymorphisms, namely rs17817449 (16q12.2, FTO gene), rs2943634 (2q36.3; intergenic region), rs6922269 (6q25.1; MTHFD1L gene), and rs10757274 (9p21.3; intergenic region). According to genome wide association studies are these SNPs assosiated with cardiovascular diseases. We genotyped DNA samples of 364 heart donors and 364 heart recipients. The results were statistically compared (using OR and Pearson's χ2 test) with the control group, which consisted of samples of individuals from the general population MONICA study. We examined the genotype in patients whose hearts failed due to dilated cardiomyopathy or coronary artery disease and then in patients with cardiac allograft vasculopathy. Furthermore, we focused on...
10

Criticality and Risk Assessment for Pipe Rehabilitation in the City of Santa Barbara Sewer System

Rossi, Rossi Carmelo, II 01 June 2015 (has links) (PDF)
Aging sewer infrastructure is posing greater and greater risk to the health and well-being of City residents. Issues can range from pipe blockages in sewer laterals to Sanitary Sewer Overflows. This thesis develops a risk analysis method that can be used by municipalities to maintain and rehabilitate sewer assets. Risk combines the effect of Likelihood of Failure (LOF) and Consequence of Failure (COF) to perform a complete two-dimensional analysis that allows for relative comparison between different pipes in the system. The LOF rating has been equated to pipe integrity while the COF rating was related to the environmental, economic, and social consequences to pipe failure. In order to estimate pipe integrity Closed Circuit Television (CCTV) scores from the City of Santa Barbara were used in combination with spatial and physical properties associated with each pipe. The CCTV scores were simply integer values between 0 and 5 based on the National Association of Sewer Services Company’s (NASSCO) Pipeline Assessment Certification Program (PACP) results. The quantitative parameters included pipe material and age, distance from restaurants, distance from any above ground water source, pipe depth below the ground surface, pipe length, and vehicular traffic volumes. The sensitivity analysis compared the given structural integrity scores with the predicted scores based on the weighted scoring method. It isolated four out of six of the parameters tested that affected the structural integrity of sewer pipes: material and age (45%), pipe depth (20%), Vehicular Traffic (10%), and distance from an above-ground water source (25%). A program was created in the C programming language that iteratively determined the percentage for each factor. These percentage factors are used to obtain the predicted structural integrity score for all the pipes. Like the LOF rating, the COF rating consisted of scores between 0 and 5. The COF rating used pipe diameter, distance from commercial zones, distance from critical infrastructure, and vehicular traffic volume as parameters for quantifying the environmental, economic, and social consequences. These factors were determined from review of past literature and given approximately equal weighting when determining the COF rating values. The environmental factor, pipe diameter, was given a percentage factor of 30%; the economic factor, distance to commercial zones, was given a percentage factor of 30%; and the social concerns, distance to critical infrastructure and vehicular traffic volume, were given percentage factors of 20% each. Finally, the risk for each pipe was determined in Geographic Information Systems (GIS) by combining the predicted structural integrity score or LOF rating and COF rating value for each pipe. This generated color-coded maps that showed distinct pipes that had the most critical predicted structural integrity scores, highest consequence, and the pipes with the most risk. This process could be used by any City to create a maintenance and rehabilitation schedule and plan for future CCTV inspections.

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