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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.
11

Risk Analysis of the applied RFID system : Project Stolpen

Grunzke, Richard January 2007 (has links)
<p>This thesis will be a risk analysis of a RFID-system for a logistical application. The system works as follows: Around Karlstad in Sweden there are three new weighing machines for lorries. The load weight will be measured for the police to control overweight and for logistical reasons such as issuing invoices and optimising the supply chain. The lorries do not have to stop to be weighed. They have to drive slowly over the weighing machine, so the loss of time is minimal. The lorries will be identified via RFID-tags. So every time a lorry will be driven over the weighing machine, the identification number and the measured weight will be logged and send to a database. In the future it is planed to store the weight on the tag itself. The task is now to analyse the RFID-communication and the transmission to the database. The thesis will contain several parts. First RFID in general and how RFID will be used in the application-scenario will be described. Next sections will be about the security and privacy requirements and the risks in detail. Then possible solutions are outlined and concrete suggestions are presented. Finally a conclusion will be drawn, which will show that the application has a low level of security.</p>
12

The impact of portfolio strategy on the property 'style' performance of UK property companies

Mohd Ali, Hishamuddin January 2001 (has links)
No description available.
13

Risk analysis associated with flank failure from Putauaki, Bay of Plenty, New Zealand

Hewitt, Dolan January 2007 (has links)
Volcanoes are dynamic evolving structures, with life cycles that are punctuated by episodes of flank instability. Putauaki (Mount Edgecumbe) is a stratovolcano located onshore in the Bay of Plenty, New Zealand. The aim of this study was to assess the stability of Putauaki and analyse the risk associated with volcanic collapse. To achieve this objective, a multidisciplinary approach was used, incorporating geomorphological and geological mapping, rock mass classification, laboratory testing to identify geotechnical properties of materials representative of the volcano, stability modelling, and analysis of landslide run-out zones. Putauaki comprises two predominant features including the larger and younger Main Cone (the summit lying 820 m a.s.l., slope angles up to 36 ), and smaller and older Main Dome (the summit lying 420 m a.s.l., slope angle of 24 ). Both features show little evidence of erosion or surface water. Rock mass description defined six lithotechnical units including indurated andesite, indurated dacite, scoriaceous andesite, altered andesite (all categorised as hard rocks), and block and ash flow and Matahina Ignimbrite (both categorised as soft rocks). The uniaxial compressive strength (UCS) of indurated andesite and indurated dacite was 60 4 MPa and 44.7 0.9 MPa respectively, correlating with moderately strong rock. Discontinuities of the indurated units were widely spaced, showed medium persistence and wide aperture, and were slightly weathered. Infill comprised predominantly loosely packed, very strong, coarse gravel. UCS of scoriaceous andesite and altered andesite was 25 5 MPa and 15 1 MPa respectively, allowing categorisation as very weak rock. Discontinuities of scoriaceous andesite were widely spaced, showed high persistence and wide aperture, and were moderately weathered. Discontinuities of the altered andesite were moderately spaced, showed low persistence and wide aperture, and were highly weathered. Infill of scoriaceous and altered andesite was loosely packed, moist, weak to very weak medium gravel. The block and ash flow was a poorly sorted, loosely packed, sandy, gravely and cobble rich matrix supported deposit. The Matahina Ignimbrite was a very weak, discontinuity-poor deposit. Shear box testing indicated cohesion and friction angle of 0 MPa and 42.1 (block and ash flow) and 1.4 x 10-3 MPa and 41.7 (Matahina Ignimbrite) respectively. These values are similar to published values. Correlation of each lithotechnical unit to its respective rock mass description site allowed approximate boundaries of each unit to be mapped. Each unit's mass strength was combined with measured bulk densities and incorporated into two dimensional slope profiles using the stability modelling package GalenaTM. Ten slope profiles of Putauaki were constructed. Failure surfaces for each slope profile were defined using the Bishop simplified multiple analysis method. Four slope profiles showed the potential for small scale failure (less than 0.1 km2 of material). The remaining six slope profiles showed the potential for large scale failure (greater than 0.1 km2 of material). Stability of these six slope profiles was investigated further in relation to earthquake force, watertable elevation, and a disturbance factor of the rock mass (D). Conditions of failure graphs for profile 6a showed that at low D (less than 0.4), earthquake forces and watertable elevation must be unrealistically high for the region (greater than 0.33 g; greater than 15% watertable elevation) in order produce a factor of safety less than 1. The remaining five slope profiles showed potential to be unstable under realistic earthquake forces and watertable elevations. Two of these profiles were unable to achieve stability at D greater than 0.8 (profile 4) and D greater than 0.9 (profile 5). A D value of 0.6 (intermediate between 0.4 and 0.8) is argued to most realistically represent Putauaki. The fact that Putauaki has not undergone large scale failure to date supports the conclusion that the constructed models overestimate the influence of those factors which promote slope instability. Maximum and minimum landslide run-out zones were constructed for the slope profiles exhibiting the potential for large scale failure. Definition of the position and extent of maximum and minimum run-out zones assumed H/L (fall height to run-out length) ratios of 0.09 and 0.18 respectively, as well as the 'credible flow path' concept. Identified impacts of landslides sourced from Putauaki include inundation of Kawerau Township, Tarawera River, forestry operations, road networks, and power supplies. Based on these impacts, the risk posed by landslides from each slope profile was categorised as ranging from relatively low to relatively high. Landslides sourced from the south-west flanks pose a relatively low risk due to their prerequisite of unrealistically high watertable elevations and earthquake forces. Landslides sourced from the north-west flanks pose a relatively high risk as minimum run-out will inundate north-east parts of Kawerau Township. Landslides sourced from the eastern flanks pose a moderate risk due to their run-out zones avoiding Kawerau Township.
14

Quantitative transportation risk analysis based on available data/databases: decision support tools for hazardous materials transportation

Qiao, Yuanhua 17 September 2007 (has links)
Historical evidence has shown that incidents due to hazardous materials (HazMat) releases during transportation can lead to severe consequences. The public and some agencies such as the Department of Transportation (DOT) show an increasing concern with the hazard associated with HazMat transportation. Many hazards may be identified and controlled or eliminated through use of risk analysis. Transportation Risk Analysis (TRA) is a powerful tool in HazMat transportation decision support system. It is helpful in choosing among alternate routes by providing information on risks associated with each route, and in selecting appropriate risk reduction alternatives by demonstrating the effectiveness of various alternatives. Some methodologies have been developed to assess the transportation risk; however, most of those proposed methodologies are hard to employ directly by decision or policy makers. One major barrier is the lack of the match between available data/database analysis and the numerical methodologies for TRA. In this work methodologies to assess the transportation risk are developed based on the availability of data or databases. The match between the availability of data/databases and numerical TRA methodologies is pursued. Each risk component, including frequency, release scenario, and consequence, is assessed based on the available data/databases. The risk is measured by numerical algorithms step by step in the transportation network. Based on the TRA results, decisions on HazMat transportation could be made appropriately and reasonably. The combination of recent interest in expanding or building new facilities to receive liquefied natural gas (LNG) carriers, along with increased awareness and concern about potential terrorist action, has raised questions about the potential consequences of incidents involving LNG transportation. One of those consequences, rapid phase transition (RPT), is studied in this dissertation. The incidents and experiments of LNG-water RPT and theoretical analysis about RPT mechanism are reviewed. Some other consequences, like pool spread and vapor cloud dispersion, are analyzed by Federal Energy Regulatory Commission (FERC) model.
15

Investigation of the distribution and risk factors associated with Mycobacterium avium subspecies paratuberculosis in cow-calf herds in Canada

Douma, Dale Peter 14 April 2011
This thesis summarizes an investigation of Mycobacterium avium subspecies paratuberculosis (Map) as a pathogen within the cow-calf industry in Canada. The specific objectives of this project were to describe the distribution of this pathogen in this industry provincially, as well as at the individual farm level in wildlife species, and in the environment. Secondary objectives of this project were to identify on-farm management risk factors that are associated with this disease and to examine potential options for herd level diagnostic capabilities. Nationally, 0.8% (95%CI = 0.4-1.1%) of the cows in the cow-calf industry were seropositive for Map with 11.7% (95%CI=7.0-16.5%) of the herds sampled having a minimum of one positive test result or 4.5% (95%CI=1.4-7.5%) of the herds having a minimum of two positive test results. The true cow prevalence was estimated as 1.8% (95%CI= 0.4 3.1). No Map was detected in any of the non-ruminant wildlife species sampled on cow-calf operations suggesting that these species were not of primary concern when dealing with the management of this disease. In a study not focussed on a cow-calf operation, Map was detected in one cluster of trapped coyote samples in a region with cow-calf production. The prevalence of Map infection in this cluster of coyotes was calculated to be 9.1% (CI: 5.7-12.5). The prevalence of infection in coyotes including all sites, ignoring the effect of clustering, was calculated to be 3.7% (CI: 2.3-5.1). The use of a commercial colostrum replacement on farm (Odds Ratio =3.96; 95% CI = 1.1014.23, p=0.035) and the presence of wild deer interacting with the cattle (Odds Ratio = 14.32; 95% CI = 1.13181.90, p=0.040) were positively associated with being a herd infected with paratuberculosis. The use of rotational grazing practices was protective (Odds Ratio = 0.20; 95% CI = 0.040.93, p=0.039). It was possible to detect environmental contamination with Map on cow-calf farms using bacterial culture and PCR for confirmation. No water samples were positive to Map; however, 6.2% of the non-water environmental samples were positive. The use of an environmental sampling protocol had a herd sensitivity of 29.6%. This finding led to a simulation modelling study to evaluate how various testing methods would compare in the broader population of cow-calf herds. The final mean risk of selecting a herd infected with Map that was not identified as positive via the herd screen test strategy was 12.9%, 9.8%, 9.6%, and 6.1% for no herd screen test, environmental sampling, ELISA serology, and pooled fecal culture strategies, respectively.
16

The Use of Risk Analysis Techniques to Determine the Probability of Producing Non-Compliant Drinking Water: Focusing on Dual Media Rapid Gravity Filtration

McAllister, Lawrence Brett January 2006 (has links)
The main goal of a drinking water treatment plant is to provide safe drinking water for its consumers. Historically, this was accomplished through monitoring the influent and effluent water quality to ensure that the water quality met a set of guidelines and regulations. However, as the limitations of relying on compliance monitoring become more evident, water utilities and drinking water treatment plants are beginning to utilize risk management frameworks to help provide safe drinking water and to mitigate potential risks. Applying a risk management framework requires an evaluation of potential risks. This systematic evaluation can be performed through using risk analysis methods. <br /><br /> The overall goal of this research is to analyze and evaluate risk analysis methodologies that are used in a variety of engineering fields, select two risk analysis methods, and use them to evaluate the probability of producing non-compliant drinking water from a rapid gravity filtration unit with respect to turbidity. <br /><br /> The risk analysis methodologies that were used in this research were the consequence frequency assessment and computer modelling combined with probabilistic risk analysis. Both of the risk analysis methodologies were able to determine the probability of producing non-compliant water from a rapid gravity filtration unit with respect to turbidity. However, these methodologies were found to provide different numerical results with respect to each other. The consequence frequency assessment methodology was found to be easier to implement; however, the consequence frequency assessment was only able to be performed on one parameter at a time. Computer modelling and probabilistic risk analysis enabled the inclusion of multiple parameters which provided a more comprehensive understanding of the filtration unit. <br /><br /> The primary conclusion from this research is that the risk analysis methods, as they are described in this thesis, are not sufficient to use directly on a rapid gravity filtration unit without further modification. Furthermore, although the risk analysis methods provided some guidance, these methods should only be used as a part of a complete risk management process.
17

The Use of Risk Analysis Techniques to Determine the Probability of Producing Non-Compliant Drinking Water: Focusing on Dual Media Rapid Gravity Filtration

McAllister, Lawrence Brett January 2006 (has links)
The main goal of a drinking water treatment plant is to provide safe drinking water for its consumers. Historically, this was accomplished through monitoring the influent and effluent water quality to ensure that the water quality met a set of guidelines and regulations. However, as the limitations of relying on compliance monitoring become more evident, water utilities and drinking water treatment plants are beginning to utilize risk management frameworks to help provide safe drinking water and to mitigate potential risks. Applying a risk management framework requires an evaluation of potential risks. This systematic evaluation can be performed through using risk analysis methods. <br /><br /> The overall goal of this research is to analyze and evaluate risk analysis methodologies that are used in a variety of engineering fields, select two risk analysis methods, and use them to evaluate the probability of producing non-compliant drinking water from a rapid gravity filtration unit with respect to turbidity. <br /><br /> The risk analysis methodologies that were used in this research were the consequence frequency assessment and computer modelling combined with probabilistic risk analysis. Both of the risk analysis methodologies were able to determine the probability of producing non-compliant water from a rapid gravity filtration unit with respect to turbidity. However, these methodologies were found to provide different numerical results with respect to each other. The consequence frequency assessment methodology was found to be easier to implement; however, the consequence frequency assessment was only able to be performed on one parameter at a time. Computer modelling and probabilistic risk analysis enabled the inclusion of multiple parameters which provided a more comprehensive understanding of the filtration unit. <br /><br /> The primary conclusion from this research is that the risk analysis methods, as they are described in this thesis, are not sufficient to use directly on a rapid gravity filtration unit without further modification. Furthermore, although the risk analysis methods provided some guidance, these methods should only be used as a part of a complete risk management process.
18

Investigation of the distribution and risk factors associated with Mycobacterium avium subspecies paratuberculosis in cow-calf herds in Canada

Douma, Dale Peter 14 April 2011 (has links)
This thesis summarizes an investigation of Mycobacterium avium subspecies paratuberculosis (Map) as a pathogen within the cow-calf industry in Canada. The specific objectives of this project were to describe the distribution of this pathogen in this industry provincially, as well as at the individual farm level in wildlife species, and in the environment. Secondary objectives of this project were to identify on-farm management risk factors that are associated with this disease and to examine potential options for herd level diagnostic capabilities. Nationally, 0.8% (95%CI = 0.4-1.1%) of the cows in the cow-calf industry were seropositive for Map with 11.7% (95%CI=7.0-16.5%) of the herds sampled having a minimum of one positive test result or 4.5% (95%CI=1.4-7.5%) of the herds having a minimum of two positive test results. The true cow prevalence was estimated as 1.8% (95%CI= 0.4 3.1). No Map was detected in any of the non-ruminant wildlife species sampled on cow-calf operations suggesting that these species were not of primary concern when dealing with the management of this disease. In a study not focussed on a cow-calf operation, Map was detected in one cluster of trapped coyote samples in a region with cow-calf production. The prevalence of Map infection in this cluster of coyotes was calculated to be 9.1% (CI: 5.7-12.5). The prevalence of infection in coyotes including all sites, ignoring the effect of clustering, was calculated to be 3.7% (CI: 2.3-5.1). The use of a commercial colostrum replacement on farm (Odds Ratio =3.96; 95% CI = 1.1014.23, p=0.035) and the presence of wild deer interacting with the cattle (Odds Ratio = 14.32; 95% CI = 1.13181.90, p=0.040) were positively associated with being a herd infected with paratuberculosis. The use of rotational grazing practices was protective (Odds Ratio = 0.20; 95% CI = 0.040.93, p=0.039). It was possible to detect environmental contamination with Map on cow-calf farms using bacterial culture and PCR for confirmation. No water samples were positive to Map; however, 6.2% of the non-water environmental samples were positive. The use of an environmental sampling protocol had a herd sensitivity of 29.6%. This finding led to a simulation modelling study to evaluate how various testing methods would compare in the broader population of cow-calf herds. The final mean risk of selecting a herd infected with Map that was not identified as positive via the herd screen test strategy was 12.9%, 9.8%, 9.6%, and 6.1% for no herd screen test, environmental sampling, ELISA serology, and pooled fecal culture strategies, respectively.
19

Profit-Based Unit Commitment and Risk Analysis

Gow, Hong-Jey 27 July 2010 (has links)
For the power market participators, there are competition and more trade opportunities in the power industry under the deregulation. In the electricity market, the bidding model is adopted instead of the cost model. GenCos try to maximize the profit under bidding model according to the power demand. Electricity becomes commodity and its price varies with power demand, bidding strategy and the grid. GenCos perform the unit commitment in a price volatile environment to reach the maximal profit. In a deregulation environment, Independent System Operator (ISO) is very often responsible for the electricity auction and secured power scheduling. The ISO operation may involve all kinds of risks. These risks include price volatility risk, bidding risk, congestion risk, and so on. For some markets, it is very important how GenCos determine the optimal unit commitment schedule considering risk management. A good risk analysis will help GenCo maximize profit and purse sustainable development. In this study, price forecasting is developed to provide information for power producers to develop bidding strategies to maximize profit. Profit-Based Unit Commitment (PBUC) model was also derived. An Enhanced Immune Algorithm (EIA) is developed to solve the PBUC problem. Finally, the Value-at-Risk (VAR) of GenCos is found with a present confident level. Simulation results provide a risk management rule to find an optimal risk control strategy to maximize profit and raise its compatibility against other players.
20

Technical, economic and risk analysis of multilateral wells

Arcos Rueda, Dulce Maria 15 May 2009 (has links)
The oil and gas industry, more than at any time in the past, is highly affected by technological advancements, new products, drilling and completion techniques, capital expenditures (CAPEX), operating expenditures (OPEX), risk/uncertainty, and geopolitics. Therefore, to make a decision in the upstream business, projects require a thorough understanding of the factors and conditions affecting them in order to systematically analyze, evaluate and select the best choice among all possible alternatives. The objective of this study is to develop a methodology to assist engineers in the decision making process of maximizing access to reserves. The process encompasses technical, economic and risk analysis of various alternatives in the completion of a well (vertical, horizontal or multilateral) by using a well performance model for technical evaluation and a deterministic analysis for economic and risk assessment. In the technical analysis of the decision making process, the flow rate for a defined reservoir is estimated by using a pseudo-steady state flow regime assumption. The economic analysis departs from the utilization of the flow rate data which assumes a certain pressure decline. The financial cash flow (FCF) is generated for the purpose of measuring the economic worth of investment proposals. A deterministic decision tree is then used to represent the risks inherent due to geological uncertainty, reservoir engineering, drilling, and completion for a particular well. The net present value (NPV) is utilized as the base economic indicator. By selecting a type of well that maximizes the expected monetary value (EMV) in a decision tree, we can make the best decision based on a thorough understanding of the prospect. The method introduced in this study emphasizes the importance of a multi-discipline concept in drilling, completion and operation of multilateral wells.

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