Modeling and evaluating information leakage caused by inferences in supply chains

While information sharing can benefit supply chains significantly, it may also have a "side effect", namely, information leakage. A limitation common to many existing solutions for preventing information leakage in supply chains is that they rely, either implicitly or explicitly, upon two unrealistic assumptions. First, what information is confidential is well known. Second, confidential information will not be revealed, if only it is not shared, regardless of how much other information is being shared. As it shall be shown in this thesis, those assumptions are not always true due to potential information leakage caused by inferences. Specifically, a conceptual model of such information leakage is proposed in this thesis. The model will enable companies in a supply chain to better understand how their confidential information may be leaked through inferences. On the basis of the proposed conceptual model, a quantitative approach is devised to evaluate the risk of information leakage caused by inferences when a given amount of information is shared. The quantitative approach will allow companies in a supply chain to measure and consequently to mitigate the risk of information leakage. Finally, a case study is discussed to illustrate how the proposed approaches work in practice

Characterisation of laser fabricated graphene materials and their application in electrochemical sensing

PhD ThesisGraphene has been publicised as the electrode material of the future due to its large surface area and excellent electrical properties. However when considering electrochemical sensors, true monolayer graphene is of limited use owing to its basal nature which results in electrochemical performance akin to basal plane pyrolytic graphite. The future of electrochemical sensing requires electrodes with performance superior to edge plane pyrolytic graphite the ‘gold standard’ of carbon electrodes. Such electrodes must not only be simple and cost effective to produce but also capable of high sensitivity and precision. Here, two new materials are presented which demonstrate excellent electrochemical responses whilst being amenable to disposable point of care sensors, akin to the planar three electrode screen printed predecessors. Laser scribed graphene and laser induced graphene both rely on a simple laser reduction method to fabricate electrodes. Laser scribed graphene, utilises the laser within Lightscribe enabled DVD drives to thermally reduce graphene oxide to a multi-layered graphene material. The expanded surface area and low oxygen content of 6.5 % result in electrochemical performance surpassing that of edge plane pyrolytic graphite. Laser induced graphene employs a CO2 laser to reduce Kapton to a highly porous graphene material. It also retains low levels of oxygen (10 %) making it an interesting prospect for electrochemical sensing. These materials have been extensively characterised physicochemically and electrochemically. Regarding electrochemistry both inner- and outer-sphere redox probes were used in comparative studies with conventional carbon based electrodes. Here the graphene electrodes demonstrated enhanced performance compared to other carbon electrodes. The heterogeneous electron transfer rate of laser scribed graphene was calculated as 0.02373 cm s−1, compared with edge plane pyrolytic graphite at 0.002601 cm s−1 and basal plane pyrolytic graphite at 0.00033 cm s−1. Electrochemical performance of such materials is clearly influenced by small changes in the oxygen content of the material but most importantly by the morphology of the electrode surface. Ability to detect biologically relevant molecules dopamine, ascorbic acid, uric acid and NADH was then investigated. Laser scribed graphene and laser induced graphene demonstrated successful simultaneous detection of dopamine, ascorbic acid and uric acid which was not achieved with edge plane pyrolytic graphite or glassy carbon electrodes. Detection limits of 0.17 μM were achieved for detection of dopamine with laser scribed 3 graphene electrodes comparing well with the literature. In conclusion both laser scribed graphene and laser induced graphene electrodes have demonstrated exceptional electrochemical behaviour with promise for future use in disposable point of care electrochemical sensors

The development of an open-source forensics platform

The rate at which technology evolves by far outpaces the rate at which methods are developed to prevent and prosecute digital crime. This unfortunate situation may potentially allow computer criminals to commit crimes using technologies for which no proper forensic investigative technique currently exists. Such a scenario would ultimately allow criminals to go free due to the lack of evidence to prove their guilt. A solution to this problem would be for law enforcement agencies and governments to invest in the research and development of forensic technologies in an attempt to keep pace with the development of digital technologies. Such an investment could potentially allow new forensic techniques to be developed and released more frequently, thus matching the appearance of new computing devices on the market. A key element in improving the situation is to produce more research results, utilizing less resources, and by performing research more efficiently. This can be achieved by improving the process used to conduct forensic research. One of the problem areas in research and development is the development of prototypes to prove a concept or to test a hypothesis. An in-depth understanding of the extremely technical aspects of operating systems, such as file system structures and memory management, is required to allow forensic researchers to develop prototypes to prove their theories and techniques. The development of such prototypes is an extremely challenging task. It is complicated by the presence of minute details that, if ignored, may have a negative impact on the accuracy of results produced. If some of the complexities experienced in the development of prototypes could simply be removed from the equation, researchers may be able to produce more and better results with less effort, and thus ultimately speed up the forensic research process. This dissertation describes the development of a platform that facilitates the rapid development of forensic prototypes, thus allowing researchers to produce such prototypes utilizing less time and fewer resources. The purpose of the platform is to provide a set of rich features which are likely to be required by developers performing research prototyping. The proposed platform contributes to the development of prototypes using fewer resources and at a faster pace. The development of the platform, as well as various considerations that helped to shape its architecture and design, are the focus points of this dissertation. Topics such as digital forensic investigations, open-source software development, and the development of the proposed forensic platform are discussed. Another purpose of this dissertation is to serve as a proof-of-concept for the developed platform. The development of a selection of forensics prototypes, as well as the results obtained, are also discussed. CopyrightDissertation (MSc)--University of Pretoria, 2009.Computer Scienceunrestricte

Nature-based tourist behavior and the conservation of natural resources : the case of Itacare in the Brazilian Atlantic forest

Le tourisme en milieu naturel connaît aujourd'hui une montée spectaculaire. Cela engendre une augmentation de la pression anthropique sur des écosystèmes fragiles. Le secteur du tourisme en milieu naturel a développé des stratégies pour gérer l'industrie du tourisme, les sites touristiques ainsi que les visiteurs. Cependant, on observe toujours des impacts écologiques négatifs causés par des comportements indésirables commis par les touristes lors d'activités et excursions touristiques. Ces impacts se produisent parce que le secteur du tourisme en milieu naturel possède peu de connaissances sur les comportements des touristes de nature. La majorité des études sur les comportements des touristes se concentrent sur la satisfaction du client et la commercialisation des destinations et peu sur la conservation des ressources naturelles des sites visités. Ce constat nous a menés à questionner la relation entre les comportements des touristes de nature et la conservation des ressources naturelles des sites visités. Par le biais d'une étude de cas conduite au village d'Itacaré, dans la forêt atlantique brésilienne, nous avons identifié deux grandes lignes pour répondre à notre questionnement : la relation que les touristes établissent avec les ressources naturelles des sites visités et la relation que les représentants du secteur du tourisme en milieux naturels établissent avec les ressources naturelles des sites où ils opèrent. Les touristes sont attirés par les milieux naturels pour vivre des expériences qui leur permettent de satisfaire leurs désirs personnels de divertissement. Certaines déficiences dans le degré d'encadrement peuvent aussi contribuer au manque de respect accordé à la conservation des environnements visités. Les visiteurs sont ainsi plus susceptibles de commettre des actions indésirables lors d'activités et excursions touristiques afin de satisfaire leurs désirs et leurs attentes. Afin de contrer et influencer les comportements des touristes de nature, le secteur du tourisme en milieu naturel doit établir une relation symbiotique entre le tourisme et l'environnement. Des activités et excursions touristiques orientées vers la communion entre les touristes et les ressources naturelles des sites visités doivent être favorisées pour que le tourisme en milieu naturel contribue au développement durable de la planète. \ud ______________________________________________________________________________ \ud MOTS-CLÉS DE L’AUTEUR : tourisme, milieu naturel, tourisme de nature, comportement des touristes, conservation des ressources naturelles, impacts écologiques

Framing China: a study of selected American newspapers' coverage of the Hainan crisis, 2001.

Lam Kwan Heung.Thesis (M.Phil.)--Chinese University of Hong Kong, 2006.Includes bibliographical references (leaves 135-137).Abstracts in English and Chinese; appendices in English with some Chinese.Abstract --- p.ii-ivAcknowledgement --- p.vTable of Contents --- p.viChapter Chapter 1 --- Introduction --- p.1-6Chapter Chapter 2 --- Literature Review --- p.7-22Chapter Chapter 3 --- Research Methods --- p.23-35Chapter Chapter 4 --- An Overview on Hainan --- p.36-46Chapter Chapter 5 --- Framing of Hainan --- p.47-92Chapter ´Ø --- International law and orderChapter ´Ø --- U.S. peacekeeping surveillanceChapter ´Ø --- Victimized U.SChapter Chapter 6 --- Framing of China --- p.93-125Chapter ´Ø --- China's skewed mediaChapter ´Ø --- China as a problematic communist stateChapter ´Ø --- China as a secretive military powerChapter ´Ø --- China's aggression towards TaiwanChapter ´Ø --- China's buying off U.S. politiciansChapter Chapter 7 --- Conclusion --- p.126-134Bibliography --- p.135-137Appendices --- p.138-18