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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.
491

Stochastic Analysis Of Storm-Surge Induced Infrastructure Losses In New York City

Hwang, Yunji January 2013 (has links)
Hurricanes are among the most catastrophic types of natural hazards, with the potential to cause serious losses in lives and property. While hurricanes rarely have a huge impact on the New York City area, they do have the potential to cause major damage to the city's transportation infrastructure. This research will deal with two main considerations--fragility curves and exceedance curves of vulnerable points in that infrastructure. The primary objective of this study is to provide a model for predicting future hurricane related storm surge patterns and for estimating possible levels of damage from future events in order to develop planning strategies to mitigate against possible damage. The first step is to describe the frequency of past storm surge events in New York City from 1920 to 2012 and determine a probability distribution for hurricane hazard about the maximum daily and yearly storm surges. The second step is to estimate potential probabilistic models by looking at the empirical data on storm surges in New York City. The last step is to concentrate on the reliability assessment for several infrastructures subjected to hurricane loading and storm surges. No significant studies have been conducted using the available empirical data on storm surge heights in New York City, despite the fact that since an observation station was installed in the Battery, New York in 1920, daily and yearly maximum water levels at that location have been documented by the National Oceanic and Atmospheric Administration (NOAA). Considering the available daily maximum sea water levels from 1920 to 2012 yields a total of 31,148 data points (2,394 days of maximum height data are unfortunately missing); 92 data points of maximum sea water levels are also available. This is the first study to utilize the nearly century's worth of empirical data obtained by the observation station at the Battery. Extensive goodness of fit testing (including the use of various probability papers) is performed on the empirical daily maximum sea water level data. It is concluded that the daily maximum sea water levels at the Battery from 1920 to 2012 follow closely a logistic distribution, with a mean value of 8.10 feet and a coefficient of variation (COV) of 9.63%. The methodology of analyzing the yearly maximum sea water levels is quite similar to that used for the daily sea water levels (and the analysis is performed independently). It is found that the yearly maximum sea water levels at the Battery from 1920 to 2012 follow closely a generalized extreme value (GEV) distribution with a mean value of 10.72 feet and a COV of 10.07%. Then, applying exact and asymptotic Extreme Value Theory, the parent GEV distribution is used to determine the probability distributions for maximum sea water levels over a range of different multi-year periods including 1, 10, 50, 100, 200, and 500 years. Finally, the total volume of flood-vulnerable infrastructure is generated and flood damage probabilities when related to the established probability distributions for sea water levels are considered. The flood vulnerabilities of different parts of the built infrastructure in New York City are studied; specifically, the subway system and the tunnel system. The concept of fragility curves is used to express these vulnerabilities. Conclusions and recommendations are provided for estimating losses probabilistically over different periods, retrofitting and strengthening the infrastructure to reduce future potential losses, and determining repair priorities. This is very useful for cost-benefit analysis.
492

DeRef: a privacy-preserving defense mechanism against request forgery attacks.

January 2011 (has links)
Fung, Siu Yuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (p. 58-63). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background and Related Work --- p.7 / Chapter 2.1 --- Request Forgery Attacks --- p.7 / Chapter 2.2 --- Current Defense Approaches --- p.10 / Chapter 2.3 --- Lessons Learned --- p.13 / Chapter 3 --- Design of DeRef --- p.15 / Chapter 3.1 --- Threat Model --- p.16 / Chapter 3.2 --- Fine-Grained Access Control --- p.18 / Chapter 3.3 --- Two-Phase Privacy-Preserving Checking --- p.24 / Chapter 3.4 --- Putting It All Together --- p.29 / Chapter 3.5 --- Implementation --- p.33 / Chapter 4 --- Deployment Case Studies --- p.36 / Chapter 4.1 --- WordPress --- p.37 / Chapter 4.2 --- Joomla! and Drupal --- p.42 / Chapter 5 --- Evaluation --- p.44 / Chapter 5.1 --- Performance Overhead of DeRef in Real Deployment --- p.45 / Chapter 5.2 --- Performance Overhead of DeRef with Various Configurations --- p.50 / Chapter 6 --- Conclusions --- p.56 / Bibliography --- p.58
493

Ochrana spotřebitele na trhu zábavní pyrotechniky / Consumer protections on the firework market

Kudrna, Vladimír January 2009 (has links)
The Thesis analyze consumer protection on fireworks market in the Czech republic in relation to harmonization with European Union legislation. First defines fireworks as such, then concentrates on the period before the application of norms of the European Union into czech law and finally on the period after their application.
494

Rozhodčí doložky ve spotřebitelských smlouvách a ochrana spotřebitele v rozhodčím řízení / Arbitration clauses in consumer contracts and protection of consumer in arbitration

Vošvrda, Jiří January 2012 (has links)
The text deals with some fundamental issues concerning arbitration clauses in consumer contracts and protection of consumers during arbitration proceedings. The purpuse of the thesis is to analyse current regulation of this field in the Czech Republic and evaluate changes brought about by amendment of Act No. 216/1994 Coll., on Arbitration and Enforcement of Arbitral Awards, which have come into force on 1st April 2012. The thesis is composed of five chapters. Chapter One is rather general and characterises major institutes of arbitration (with regard to disputes arising out of consumer contracts). Its eleven parts report on definition of arbitration and its forms, its inclusion among ADR mechanisms, reflections on suitability of arbitration in consumer disputes, its history and recent development, legal sources, basic principles, advantages and disadvantages in consumer disputes, main doctrines and fundamental conditions for arbitration (arbitrability and arbitration agreement). Chapter Two focuses on so-called "arbitration centres". The chapter consists of for parts. Part One describes their legal status. Part Two refers to recent discussions about admissibility of arbitration clauses recommended by centres. The next part seeks to draw attention to critical views of case law mentioned in the previous...
495

An exploration into the experiences of police officers who investigate child protection cases and secondary traumatic stress

MacEachern, Alison January 2011 (has links)
Child protection is an area of Police work that has grown in the last decade, involving Police Officers working in departments that specialise in the investigation of cases of child abuse. Although Police Officers in this field may be at greater risk of experiencing Secondary Traumatic Stress (STS), there remains a paucity of research in this area of policing. Analogies can be drawn to existing research in policing and with social service workers involved in child protection.A mixed methodology was used to conduct the study and involved a self-completion postal questionnaire, followed up by a longitudinal case study of three of the trainee Detective Officers. The questionnaire sample consisted of 63 Detective Officers involved in the investigation of child abuse within the host Police Force, including Detective Constables, Sergeants and Inspectors.The Study found that 51% of the respondents experienced a degree of STS, findings that are suggestive that STS is being experienced by a significant portion of Detective Officers who, as part of their daily duties, investigate child protection cases. The longitudinal case study found that 2 out of the 3 cases indicated that their views and experiences of the symptoms of STS changed mid way through their training.The implications for Police Forces to provide safe working environments and appropriate counselling for employees as a tool to manage stress, to inform practice and from which the basis of reasonable precautions, risk assessments, monitoring and appropriate interventions will be discussed.
496

A study of two problems in data mining: anomaly monitoring and privacy preservation.

January 2008 (has links)
Bu, Yingyi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 89-94). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Anomaly Monitoring --- p.1 / Chapter 1.2 --- Privacy Preservation --- p.5 / Chapter 1.2.1 --- Motivation --- p.7 / Chapter 1.2.2 --- Contribution --- p.12 / Chapter 2 --- Anomaly Monitoring --- p.16 / Chapter 2.1 --- Problem Statement --- p.16 / Chapter 2.2 --- A Preliminary Solution: Simple Pruning --- p.19 / Chapter 2.3 --- Efficient Monitoring by Local Clusters --- p.21 / Chapter 2.3.1 --- Incremental Local Clustering --- p.22 / Chapter 2.3.2 --- Batch Monitoring by Cluster Join --- p.24 / Chapter 2.3.3 --- Cost Analysis and Optimization --- p.28 / Chapter 2.4 --- Piecewise Index and Query Reschedule --- p.31 / Chapter 2.4.1 --- Piecewise VP-trees --- p.32 / Chapter 2.4.2 --- Candidate Rescheduling --- p.35 / Chapter 2.4.3 --- Cost Analysis --- p.36 / Chapter 2.5 --- Upper Bound Lemma: For Dynamic Time Warping Distance --- p.37 / Chapter 2.6 --- Experimental Evaluations --- p.39 / Chapter 2.6.1 --- Effectiveness --- p.40 / Chapter 2.6.2 --- Efficiency --- p.46 / Chapter 2.7 --- Related Work --- p.49 / Chapter 3 --- Privacy Preservation --- p.52 / Chapter 3.1 --- Problem Definition --- p.52 / Chapter 3.2 --- HD-Composition --- p.58 / Chapter 3.2.1 --- Role-based Partition --- p.59 / Chapter 3.2.2 --- Cohort-based Partition --- p.61 / Chapter 3.2.3 --- Privacy Guarantee --- p.70 / Chapter 3.2.4 --- Refinement of HD-composition --- p.75 / Chapter 3.2.5 --- Anonymization Algorithm --- p.76 / Chapter 3.3 --- Experiments --- p.77 / Chapter 3.3.1 --- Failures of Conventional Generalizations --- p.78 / Chapter 3.3.2 --- Evaluations of HD-Composition --- p.79 / Chapter 3.4 --- Related Work --- p.85 / Chapter 4 --- Conclusions --- p.87 / Bibliography --- p.89
497

Attack and protection issues in online social networks. / 在線社交網絡上的攻擊與保護問題 / Zai xian she jiao wang luo shang de gong ji yu bao hu wen ti

January 2011 (has links)
Mo, Mingzhen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (p. 111-123). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Thesis Contributions --- p.5 / Chapter 1.3 --- Problem Description --- p.6 / Chapter 1.4 --- Thesis Organization --- p.8 / Chapter 2 --- Background Study --- p.11 / Chapter 2.1 --- Overview --- p.11 / Chapter 2.2 --- Problem Definitions --- p.12 / Chapter 2.3 --- Privacy in Online Social Networks --- p.14 / Chapter 2.4 --- Attack --- p.17 / Chapter 2.4.1 --- Statistical Learning --- p.18 / Chapter 2.4.2 --- Graph Theory --- p.22 / Chapter 2.5 --- Protection --- p.23 / Chapter 2.5.1 --- Clustering-Based Approach --- p.24 / Chapter 2.5.2 --- Modification-Based Approach --- p.27 / Chapter 3 --- Exploit Social Networks with SSL --- p.30 / Chapter 3.1 --- Overview --- p.31 / Chapter 3.2 --- Semi-Supervised Learning Framework --- p.35 / Chapter 3.2.1 --- Co-Training SSL --- p.36 / Chapter 3.2.2 --- Graph-Based SSL --- p.38 / Chapter 3.2.3 --- Local and Global Consistency Graph-Based SSL --- p.39 / Chapter 3.3 --- Experiment --- p.40 / Chapter 3.3.1 --- Dataset Description --- p.41 / Chapter 3.3.2 --- Data Preprocessing --- p.43 / Chapter 3.3.3 --- Experiment Process --- p.45 / Chapter 3.3.4 --- Experiment Results --- p.47 / Chapter 3.4 --- Conclusion --- p.49 / Chapter 4 --- Exploiting Social Networks with CG SSL --- p.50 / Chapter 4.1 --- Overview --- p.51 / Chapter 4.2 --- Exploit Learning Model and Algorithms --- p.56 / Chapter 4.2.1 --- Exploit Learning Model --- p.57 / Chapter 4.2.2 --- Algorithms --- p.60 / Chapter 4.2.3 --- Community Generation --- p.65 / Chapter 4.3 --- Experiment --- p.66 / Chapter 4.3.1 --- Dataset Description --- p.67 / Chapter 4.3.2 --- Data Preprocessing --- p.70 / Chapter 4.3.3 --- Experiment Process --- p.72 / Chapter 4.3.4 --- Experiment Results --- p.77 / Chapter 4.4 --- Conclusion --- p.82 / Chapter 5 --- APA Comparison Scheme --- p.83 / Chapter 5.1 --- Overview --- p.84 / Chapter 5.2 --- Attack-Protect-Attack (APA) Comparisons Scheme --- p.87 / Chapter 5.2.1 --- Algorithm --- p.87 / Chapter 5.2.2 --- Attack & Protection Approaches --- p.88 / Chapter 5.3 --- Experiment --- p.91 / Chapter 5.3.1 --- Dataset Description --- p.92 / Chapter 5.3.2 --- Data Preprocessing --- p.92 / Chapter 5.3.3 --- Experiment Process --- p.94 / Chapter 5.3.4 --- Experiment Result --- p.95 / Chapter 5.4 --- Conclusion --- p.103 / Chapter 6 --- Conclusion and Future Work --- p.105 / Chapter 6.1 --- Conclusion --- p.105 / Chapter 6.2 --- Future Work --- p.107 / Bibliography --- p.111
498

L’impact de la protection sociale sur le rendement des ressources humaines : Le cas du secteur informel au Sénégal / The impact of social protection on human performance : The case of the informal sector in Senegal

Ndour, Farba 11 January 2013 (has links)
Eu égard les ressources financières conséquentes qu’elle mobilise, la protection sociale exerce une influence sur l’économie et sur les hommes. Son efficacité suscite de multiples débats, alimentés par le ralentissement économique, opposant partisans d’un libéralisme accru et défenseurs de davantage de justice sociale. Pour les premiers, le coût des dépenses sociales et leurs effets d’aubaine constituent un frein pour l’économie alors les seconds assimilent son apport à un levier indispensable au développement du capital humain. Cette thèse cherche à démontrer que les performances économiques et politiques sociales peuvent et doivent poursuivre des objectifs communs afin que le développement économique se traduise par le développement humain. Elle s’organise en deux parties comportant chacune trois chapitres. Dans un premier temps, suite à une démonstration mettant en exergue la forte corrélation entre niveau de développement économique et qualité des ressources humaines,seront mis en évidence deux positionnements contradictoires à propos de l’apport de la protection sociale sur l’économie et sur les hommes. A l’instar des autres pays en développement, au Sénégal, le secteur informel, représentant le poumon de l’économie malgré une faible productivité, est dépourvu de toute forme de couverture sociale moderne. Aboutissant à la conclusion que certaines composantes de la protection sociale, telle que l’assurance maladie, peuvent améliorer l’efficacité du capital humain, nous esquissons un schéma de couverture médicale applicable au secteur informel au Sénégal dans le cadre d’une assurance maladie obligatoire. / Considering the substantial financial resources that social protection mobilizes, it exerts influences on the economy and population. Many debates are raised about its effectiveness, and these debates are sustained by the economic slowdown, that opposes supporters of an increased liberalism and those who are for some more social justice. For the former, the social spending cost and stroke of luck act as a brake on the economy while the latter compare its contribution to an essential lever for the development of human capital. This thesis tries to demonstrate that economic performance and social policies can and should pursue common goals, so that economic development should result in human development. It is divided into two parts, with three chapters in each. Firstly, two conflicting positions about the contribution of social protection on the economy and population will be brought out following a demonstration which underlines the strong correlation between the level of economic development and quality of human resources. Like the other developing countries,in Senegal the informal sector, which represents the hub of the economy, despite its low productivity, has no form of modern social coverage. Coming to the conclusion that some components of social protection, such as health insurance, can improve the effectiveness of human capital, we outline a scheme of medical coverage which can be applied to the informal sector in Senegal through compulsory health insurance.
499

An Evaluation of Norovirus Persistence in Estuarine Water and of Methods for its Detection in Treated Sewage Effluent

Fagan, Margaret H. 01 January 2008 (has links)
No description available.
500

Toxicology of Decabromodiphenyl Ether in Avian Embryos: Disposition of the Flame Retardant BDE-209 in Yolk-Injected Chicken Embryos (Gallus gallus)

Sifleet, Samantha D. 01 January 2009 (has links)
Polybrominated diphenyl ethers (PBDEs) are flame retardant chemicals of toxicological concern present in humans, wildlife, and the environment. Deca-BDE is the highest production product due to historical use patterns and recent regulatory limitations on the other two commercial formulations (Penta-BDE and Octa-BDE) in the U.S and Europe. The EU banned Deca-BDE starting July 1, 2008. However, it remains in usage in North America and elsewhere in the world. BDE-209 is the dominant congener in all Deca- BDE commercial products. BDE-209 has been reported to under go metabolic debromination to lesser brominated and more toxic and bioaccumulative congeners. However, insufficient data are available on this process. It has also been observed that congener profiles and BDE-209 levels in terrestrial organisms differ from most aquatic species, indicating accumulation or metabolic dissimilarity. The goal of this in ovo study is to determine the biotransformation and tissue distribution of BDE-209 after injection into the yolk-sac of embryonic chickens. An emulsion formulation was employed to better distribute the hydrophobic BDE-209 within the eggs in an attempt to better mimic “natural” exposure of embryos. Acute mortality from BDE-209 yolk injection was observed. An LD50 value of 44 μg/egg (740 ng/g ww) was determined for embryonic chickens in this study. Concentrations of BDE-209 and possible metabolic degradates were determined in five compartments of the embryos (yolk, brain, liver, heart and remaining carcass). The results indicated that some BDE-209 was mobilized from the yolk, into the carcass, liver, brain, and heart tissues of the developing chicken embryo prior to pipping. However, 80% of the dose was detected as BDE-209 in the yolk sac. Additional BDE-209 would likely have been assimilated following hatching and resorption of the remaining yolk. Nona-BDEs were detected in all of the liver and yolk samples from BDE-209 exposed eggs. The congener profiles of the different tissues did not indicate that significant metabolic debromination of BDE-209 occurred within the developing embryos.

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