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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.
151

GIS-Based Probabilistic Approach for Assessing and Enhancing Infrastructure Data Quality

Saliminejad, Siamak 1983- 14 March 2013 (has links)
The task of preserving and improving infrastructure systems is becoming extremely challenging because these systems are decaying due to aging and over utilization, have limited funding, and are complex in nature (geographically spread, and affect and are affected by technological, environmental, social, security, political, and economic factors). The infrastructure management paradigm has emerged to assist in the challenging task of managing infrastructure systems in a systematic and cost-effective manner. Infrastructure management is a data-driven process. It relies on large databases that contain information on the system’s inventory, condition, maintenance and rehabilitation (M&R) history, utilization, and cost. This data feeds into analytical models that assess infrastructure current conditions, predict future conditions, and develop optimal M&R strategies. Thus, complete and accurate data is essential to a reliable infrastructure management system. This study contributes to advancing the infrastructure management paradigm (with focus on pavement management) in two primary ways: (a) it provides in-depth understanding of the impact of errors in condition data on the outputs of infrastructure management systems, and (b) it provides efficient computational methods for improving infrastructure data quality. First, this research provides a quantitative assessment of the effects of error magnitude and type (both systematic and random) in pavement condition data on the accuracy of PMS outputs (i.e., forecasted needed budget and M&R activities in a multi-year planning period). Second, a new technique for detecting gross outliers and pseudo outliers in pavement condition data was developed and tested. Gross outliers are data values that are likely to be erroneous, whereas pseudo outliers are pavement sections performing exceptionally well or poor due to isolated local conditions. Third, a new technique for estimating construction and M&R history data from pavement condition data was developed and tested. This technique is especially beneficial when M&R data and condition data are stored in disparate heterogeneous databases that are difficult to integrate (i.e., legacy databases). The main merit of the developed techniques is their ability to integrate methods and principles from Bayesian and spatial statistics, GIS, and operations research in an efficient manner. The application of these techniques to a real-world cases study (pavement network in Bryan district) demonstrated the potential benefits of these techniques to infrastructure managers and engineers.
152

Sustainable streets and highways: an analysis of green roads rating systems

Eisenman, Ana Athalia Plaut 06 April 2012 (has links)
As sustainability increasingly becomes a concern to society, it is in state transportation agencies' best interests to embrace and adopt initiatives that will both educate their employees and the communities they serve on how transportation systems and system operations can be viewed within such a context. One of the strategies some state departments of transportation (SDOTs) have adopted for providing a more sustainable approach to highway design is a "green streets and highways rating system." Adopting a strategy such as the one proposed in this thesis for the Georgia Department of Transportation will enable an agency to compare projects based on sustainability goals and outcomes. Such a rating system can provide several benefits to a state department of transportation. As a public relations tool, publishing the sustainability rating results of completed projects can promote an "environmentally friendly" image of the agency. In some cases, this could be used to garner increased support for an agency's program. Comparing the ratings of proposed projects during the early programming process may also help in the selection of more sustainably effective and efficient projects. Additionally, a project in the project planning phase could use the green rating criteria to identify those areas where changes in design could result in more environmentally sensitive designs. A green streets and highways rating tool is an important means of fostering an environmental ethic in a transportation agency, one that could become more important in years to come.
153

Posouzení možností napadení vodní kritické infrastruktury teroristy v Královéhradeckém kraji / Examination of proposal attacking on water critical infrastructure by terrorists in the region of Hradec Králové

DOLEJŠKA, Luboš January 2012 (has links)
This master thesis mentions the brief information about Hradec Králové region in the first chapter. It is focused on the characterization of water as a basic structural element of life on the Earth. The information about underground water, water sources and its distribution, drainage, water ducts and towers, water storages and the protection and the future of the water were necessary to mention in the context of this part of the master thesis. The master thesis brings the information about the way to lead water from the sources to the final consumers. It was also focused on the wide theme of terrorism, the master thesis has no sense without mentioning of these basic information. The water critical infrastructure could be damage by its usage in Hradec Králové region. The infrastructure and the critical infrastructure were compiled in detail in the last part of the contemporary state of this master thesis to make up better idea about its parts. The aim of this master thesis was to explore the possibilities of the attack of the critical water infrastructure in Hradec Králové region by the terrorists. As one of the method for the elaboration of the contemporary state was used the collection of the relevant literature in the master thesis. The subsequent background research method results from this collection of the relevant literature. The method FMEA (Failure Mode & Effects Analysis) classified as a method of the compilation risk analysis was the another method which was used for the evaluation of the outcomes from the guided interviews. With success we can tell that the critical infrastructure is sufficiently protected against the potential terroristic attacks in the specific places in Hradec Králové region.
154

Risks associated with infrastructure project finance in developing countries: the case of Zambia

Mweemba, Bruno N January 2015 (has links)
Since the enactment of the Public Private Partnership (PPP) Act of 2009, there has not been a single successful PPP transaction entered into between the Government of Zambia and any private sector entity under the PPP Act of 2009 (Zambia Development Agency, 2014: 7). According to the Zambia Development Agency (2014:7), 75% of the PPPs that were entered into by the government of Zambia prior to the promulgation of the PPP Act of 2009 were canceled. These include: the Kasumbalesa Border Post, Mpulungu Harbour and Railways Systems of Zambia with an exception of the 65 year concession of the Luburma Market (popularly known as Kamwala Market). These cancellations of PPP concessions coupled with revelations in the Zambian Parliament that concession documentation for the Luburma market which is the only surviving PPP had since gone missing, this led to the research problem statement with an assertion that risks associated with infrastructure project finance are endemic in Zambia. In seeking to explore the validity of this assertion, three research objectives guided the study, namely: assessing Zambia’s general infrastructure project finance and PPP framework in comparison to theoretical normative criteria and selected country experiences; identifying and rating risks through a questionnaire; and proposing an ideal project finance risk management model which can be used as a reference by sponsors in Zambia as they design and structure infrastructure project finance deals. On a scale of 1-5 which was guided by the overal risk score outlined in the study, the average mean score ranking for all the 40 risks under investigation was found to be 3.25 .This indicates that the sentiments among respondents is that risks associated with infrastructure project finance in Zambia are average and not endemic as was affirmed in the problem statement. Despite this ‘comforting’ statistical result, the little progress in terms of earmarked infrastructure PPP deals coupled with deal cancellations as outlined above may be an indication that even the average risks appear to impede on the development of project finance and PPPs in Zambia. There is therefore an urgent need for Government and other relevant stakeholders to begin paying attention to some of the risks discussed in this study especially those with a mean score ranking in excess of 3.50 (high risk). The study in chapter 9 provides recommendations which are grouped under four key headings: addressing the environment for PPPs; providing capacity to procuring entities; paying attention to critical success factors for project development; as well as exploring a variety of possible credit enhancement mechanisms such as guarantees as a way of wooing project investors and improving the bankability of planned infrastructure deals. The Government of Zambia is further advised to avoid using ‘political feasibility “as the core investment criteria in the infrastructure agenda for the country. The study encourages that conventional benchmarks which are a mix of technical soundness, economic viability, environmental and social sustainability, financial/commercial viability as well as market readiness remain the core guiding principle in the project identification process. This will be the only way to avoid developing “white elephants” that may perpetually be a burden to the treasury and tax payers.
155

Assessing the transportation of liquid fuels in South Africa using multi-criteria decision analysis: a conceptual framework and case study

Coelho, Marco January 2016 (has links)
With the recent unprecedented growth of many African economies, infrastructure investment has been flooding into the continent. Two key areas experiencing large growth in infrastructure development are the transport and energy sectors. This trend also continues to hold true in the South African development framework. The theme of this thesis encompasses both subjects of energy and transportation infrastructure which feature prominently in the countries development plans. When energy is discussed in South Africa, it is usually in the context of power generation and electricity distribution. This study focuses on another key component of the energy sector in the form of liquid fuel. Most of this energy is consumed for transportation purposes. The energy consumption of the transport sector in South Africa is large, totalling around 28% of Total Final Consumption (TFC) in the national energy balances. The bulk of this energy demand (97%) is in the form of liquid fuels, accounting for 84% of the national liquid fuel demand. This thesis focusses on the investigation of a Multi Criteria Decision Analysis (MCDA) model, which can be used to aid decision makers in the planning and assessment of liquid fuel transportation projects. A key feature of this thesis is the incorporation of a stochastic analysis in the MCDA model. There are two key motivations for assimilating a stochastic analysis in this investigation. The first one is the evaluation of incorporating such an analysis in an MCDA, as opposed to a more traditional sensitivity analysis. The second motivation is to assess the value of employing stochastic analysis as an input method for analysing a decision problem, where comprehensive field data can be substituted for a relevant range of simulated data. This thesis proposes a model which integrates the MCDA and stochastic analysis in the hope that it would provide a faster and more cost effective alternative for assessing certain liquid fuel transportation problems.
156

Assessing Maintenance and Management of Infrastructure Systems Using Citizen Reported Service Requests

Bolte, Taylor Clark 19 March 2019 (has links)
Maintaining current and future infrastructure will require smart practices to help better meet user needs with fewer financial resources. The recent adoption of information communication technologies, such as, 311-call centers enables city agencies to detect and more quickly respond to real-time infrastructure system service disruptions and maintenance requests. Of the 200 or more cities that use 311, New York City's system is the largest, receiving more than 19.5 million citizen requests since 2010. Current citizen service requests made through 311 range from issues about street and sidewalk conditions to problems with their water, sanitation, snow removal, and traffic congestion. In the first manuscript, service requests were compared to socio-economics within zip codes. Zip codes were clustered by four socio-economic variables including median house value, percent of the population with a bachelor's degree, unemployment rate, and percent non-white to represent socio-economic differences between zones in the city. Results show that citizens from low socio-economic areas, meaning those with low median house values, low population with a bachelor's degree, high unemployment, and high percent non-white are burdened with significantly more infrastructure maintenance requests. When controlling for physical differences such as miles of road, total frequency of calls, and the number of people per zip code, people from low socio-economic zones are more likely to call about issues related to street conditions, sanitation, and their water system. In the second manuscript, service request response time by agency were compared based on location and socio-economic variables. The location of the call based on borough and the socio-economic characteristics of the zip code do significantly influence agency response time. Citizens reporting issues in Queens can expect to wait significantly longer, about 3 days more, to receive a response for a similar request in other boroughs of New York City. This is for issues about water, sewer, traffic lights, and street condition. The Department of Transportation, Department of Sanitation, and the New York Police Department respond significantly faster to service requests in zones classified with high and middle socio-economic groups compared to zip codes with low socio-economic groups of people. These differences in geography and socio-economic characteristics suggest unequal treatment of maintenance issues. These differences in response may expose an implicit bias in maintenance response. By recognizing these differences, city engineers can begin to prioritize maintenance issues based on how communities perceive infrastructure in need of repair, and thus better meet the needs of individual citizens in the future. / Master of Science / Infrastructure includes systems including buildings, roads, water/wastewater, trash, and various other networks that facilitate citizens everyday lives. These infrastructure systems will always require maintenance in order to keep it running effectively and efficiently. Using smart and sustainable practices in this process can help better meet user needs, while saving more money. Using more technology such as 311-call centers can allow cities to detect and more quickly respond to real-time infrastructure disruptions and maintenance issues. 311 call centers receive calls about anything from street condition problems such as potholes to problems with their drinking water. Of the 200 or more cities that use 311, New York City’s system is the largest, receiving more than 20 million citizen requests since 2010. The first manuscript looks into what certain types of people call about. Using zip codes, areas of the city were grouped together based on four socio-economic variables; median house value, percent of the population with a bachelor’s degree, unemployment rate, and percent non-white. People from low socio-economic areas, meaning those with low median house values, low population with a bachelor’s degree, high unemployment, and high percent non-white call more about infrastructure maintenance requests. When controlling for physical aspects of these areas such as miles of road, total amount of calls, and the number of people per zip code, people from low socio-economic areas are more likely to call about issues related to street conditions, sanitation, and their water system. The second manuscript looks into how long it takes government agencies to respond and resolve these calls. The location of the call based on location in the city and the socio-economic characteristics of the zip codes have an effect on agency response time. People reporting issues in Queens can expect to wait much longer, about 3 days more, to receive a response for a similar issue called from another borough of New York City. The Department of Transportation, Department of Sanitation, and the New York Police Department respond significantly faster to service requests in areas with high and middle socio-economic status groups compared to zip codes with low socio-economic groups of people. By knowing that location and socio-economic status matter when citizens call 311, city engineers can begin to use this data to help prioritize maintenance issues based on specific areas and needs of individual people in the future. These differences in location and socio-economic characteristics could possibly suggest unequal treatment of maintenance issues. However, since the differences seen in this research are with only certain variables accounted for, further research will be needed to help show possible causation for these differences.
157

A study of the economic infrastructure and organisation of the specialeconomic zone (Shenzhen) of the Peoples' Republic of China from aninvestor's point of view

車德明, Che, Tak-ming, Brian. January 1984 (has links)
published_or_final_version / Business Administration / Master / Master of Business Administration
158

Vulnerability analysis of electric power delivery networks

Holmgren, Åke January 2004 (has links)
<p>Disturbances in the services provided by the infrastructuresystems—e.g. electric power supplies and communications—can have serious implications for everyday life,economic prosperity and national security. The disturbances canbe initiated by natural disasters, adverse weather, technicalfailures, human errors, sabotage, terrorism or acts of war. Theaim of this thesis is to study methods for proactivevulnerability analysis of electric power delivery networks(i.e. to analyze their sensitivity to threats and hazards), andto formalize vulnerability as a theoretical concept.</p><p>The thesis consists of three papers. In the first paper, wediscuss concepts and perspectives for developing a methodologyfor vulnerability studies with the help of the followingthemes: The properties of the infrastructure systems, threatsand hazards, vulnerability and consequence analysis, andmeasures for creating robust and resilient systems.</p><p>In the second paper we discuss how to assess vulnerabilityof power delivery systems with the help of standard powersystem performance indices. In two case studies, Swedish powerdelivery disturbance data is analyzed with statistical methods.We demonstrate that the disturbance size of large disturbancesfollows a power law distribution, and that the time betweendisturbances is exponentially distributed.</p><p>In third paper, we model electrical power networks asgraphs, and conduct empirical studies of two power transmissiongrids. We calculate values of topological characteristics ofthe networks and compare their error and attack tolerance, i.e.their performance when vertices are disabled, with twofrequently used model networks. Further, we perform a graphinfluenced vulnerability analysis of a fictitious powernetwork, and evaluate di.erent strategies to decrease thevulnerability of the system.</p>
159

Branch plant dependency and developmental possibilities in the local economy : the case of Wrexham Maelor

Douglas, Calbert Henry January 1994 (has links)
No description available.
160

Spatial setting of manufacturing activities in the metropolitan cities of developing countries : the example of Dhaka, Bangladesh

Hasan, Sayed Mahmudul January 1998 (has links)
No description available.

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