M.Com. (Computer Science) / The area covered in this study is that of logical security models. A logical security model refers to the formal representation of a security policy which allows the subsequent movement of rights between subjects and objects in a system. The best way to illustrate the goal of this study, is with the following abstract from the submitted article, which originated from this study. 'The original protection graph rewriting grammar used to simulate the different operations of the Take/Grant model is reviewed. The productions of the PGR-grammar is then expanded, by adding a new context which is based on the different security classes found in the Bell Grid LaPadula model [14].' The first goal of this study was to take the Take/Grant security -model and expand it. This expansion included the concept of assigning a different security class to each subject and object in the model. This concept was derived from the Bell and LaPadula model as discussed in chapter 2 of this study. The next goal that was defined, was to expand the PGR-grammar of [28], so that it would also be able to simulate .the operations of this expanded Take/Grant model. The .PGR-grammar consisted of different permitting and forbidding node and edge contexts. This PGR-grammar was expanded by adding an additional context to the formal representation. This expansion is explained in detail in chapter 5 of this study. The third goal was to take the expansions, mentioned above, and implement them in a computer system. This computer system had to make use of an expert. system in order to reach certain conclusions. Each of the operations of the Take/Grant model must be evaluated, to determine whether that rule can be applied or not. The use of the expert system is explained in chapters 6 and 7 of this study. This study consists out of eight chapters in the following order. Chapter 2 starts of with an introduction of some of the most important logical security models. This chapter gives the reader background knowledge of the different models available, which is essential for the rest of the study. This chapter, however, does not discuss the Take/Grant model in detail. This is done in chapter 3 of the study. In this chapter the Take Grant model is discussed as a major input to this study. The Send Receive model is also discussed as a variation of the Take/Grant model. In the last section of the chapter a comparison is drawn between these two models. Chapter 4 formalizes the Take/Grant model. The protection graph rewriting grammar (PGR-grammar), which is used to simulate the different operations of the Take/Grant model, is introduced...

The two centuries from 1818 to 2004 cover profound social and economic changes in what was, for much of the period, the most powerful country in the world. Britain led the way in moving capital and labour out of agriculture and into newer industries, such as coal-mining, textiles and transportation. The changes were accompanied by deep institutional changes, especially in the franchise. The rate of change is remarkable: within seventy years Britain was almost completely democratic, in contrast to the 'rotten boroughs' and virtual feudalism of the pre- 1832 unreformed Parliaments. The changes are mirrored in the role given to agriculture within society, and in particular the amount and type of economic rent transferred from the consumer and the taxpayer to the farmer. This thesis uses two centuries of data and 'survival analysis' statistical techniques to show that Olson's celebrated theory of collective action can be substantiated in a dynamic context. I show that as the share of farmers in the workforce diminishes, and their relative wealth shrinks, the probability of the Cabinet increasing protection grows. The reverse is also the case, showing that the Cabinet responds positively to pressures from a group whose utility was diminishing. / Land and Food Systems, Faculty of / Graduate

Information has become so pervasive within enterprises and everyday life, that it is almost indispensable. This is clear as information has become core to the business operations of any enterprise. Information and communication technology (ICT) systems are heavily relied upon to store, process and transmit this valuable commodity. Due to its immense value, information and related ICT resources have to be adequately protected. This protection of information is commonly referred to as information security.

As urban areas increase in population, pressures are exerted upon vacant or undeveloped lands for housing, industry, public buildings, highway rights-of-way, and a host of other uses including parks. At the same time, pressures are placed upon existing parks to accomodate some of the other needs of expanding urban areas. The loss of lands that have been developed for recreation results in either the loss of a necessary activity or the reduction of the quality of the experience enjoyed by park users. Studies in the U.S.A. indicate that alienation of park lands by non-recreative uses is a serious problem. While many urban areas in Canada have experienced significant population increases and the resultant pressures on urban land during the last ten years, there has been no examination, on a provincial or national basis, of the effects of such trends on major parks (over 20 acres). Are park lands in this size category being alienated to provide land for non-recreative purposes? This thesis attempts to provide an answer to this and related questions. The findings of this study are based on 141 questionnaire returns from a survey of 234 Canadian municipalities with populations over 10,000. Two of 183 municipalities between 10,000 and 50,000 persons experienced a total of 5 alienations from 1960-1970. Seventeen of 51 municipalities over 50,000 persons experienced a total of 34 alienations during the same period. The land alienated was 13 per cent of the total park area affected; on the average, 15.5 acres of land were alienated per encroachment. Highways and roads, schools, and housing were the main uses alienating park lands. In most cases objections to the alienation by the parks board were overruled by the municipal council on the grounds that the encroaching use was of greater importance or that the land was cheaper. It is concluded that alienation of park lands in Canadian municipalities is a significant problem that to date has been unrecognized and un-publicized. Moreover, the study suggests that pressure on park lands will continue to mount in the foreseeable future. With the exception of parks given to a municipality in trust there is little to indicate that municipal legislation is oriented to protecting the major parks. In fact, parks that have been dedicated by public referendum are not guaranteed perpetual protection in all provinces. Parks, as viewed by some municipal councils, seem to represent a valuable form«of land bank for future development needs. The increasing public awareness of the value of major parks in urban areas may change this outlook in the future. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

The Code of Banking Practice of South Africa should be used to put a duty on banks to assist their clients in the event of chargebacks. This text takes a pragmatic look at the code, the contracts between clients and banks, and tests a few cases against the paid vs delivered concept behind SAMOS. / Mini-dissertation (LLM)--University of Pretoria, 2016. / Mercantile Law / LLM / Unrestricted

Kevin McGrath Abstract This thesis looks to assess the role of public-private partnerships (PPPs) in building critical energy infrastructure, and its implications for energy and national security. The clear majority of academic literature in energy security focuses exclusively on energy supply, and demand, but there is little written on the security issues facing countries when financing critical energy infrastructure projects. Through assessing the (1) recent history of privatization, (2) the development of the domestic PPP model, and (3) current relationships with PPPs in Canada, the United States, the United Kingdom, and France this thesis will look to identify the underlying domestic cultural normative debate which is driving policy making decisions. By understanding the general historical trends of privatization, and economic ideologies in governments over the past 40+ years, we can see the current and future trends in building critical energy infrastructure. By understanding the constantly evolving factors, and interdependencies at play, this thesis highlights the role of public-private partnerships in critical energy infrastructure, and energy security in general.

The purpose of this present study is to understand the role of habit in information security behaviors. The automatic aspect of habit and its impact on secure behavior and the intention-behavior relationship was explored in this dissertation through the lens of protection motivation theory. Three secure behaviors were selected for the investigation after following a rigorous process to identify habitual secure behaviors. The three behaviors that were investigated are: locking the PC when leaving it unattended, verifying the recipient email addresses before sending email and visiting only verified websites. Separate pilot studies were conducted for each of the behaviors followed by a main investigation. Habit was measured with a first-order reflective and second-order formative scale that captured the multidimensional aspects of habit: Lack of Awareness, Uncontrollability and Mental Efficiency. Data were collected for each of the behaviors separately via separate online surveys using Amazon Mechanical-Turk. The results of the data analyses indicate that habit significantly influence the performance of secure behavior while negatively moderating the intention-behavior relationship for each of the three behaviors. The findings also confirm that when certain behaviors are habitual, the cognitive resources needed to make decisions on performing behavior reduce. Several alternate models were analyzed as a part of the post hoc phase of the study. The findings of this study provide several contributions to the IS research and practice. This study investigated the role of habit in an information security context using a second-order formative scale. The findings indicate that habit play a significant role in the performance of secure behaviors and verifies the relationship between intention and behavior in an information security context. The findings provide directions to organizations in understanding habits of their employees and to foster positive habits while breaking negative habits. The findings of this study provide several future research directions and highlight the importance of further exploration of habit in an information security context.

Investigations of environmental hormone contamination commonly utilize solidphase extraction (SPE) followed by high-performance liquid chromatography / (electrospray ionization) tandem mass spectrometry (HPLC/(ESI)MS2) in the detection of estrogens. Matrix interference is widely reported. In this study, androgens were targeted alongside estrogens as environmentally co-introduced endocrine disrupting chemicals. Analytical methods were developed in parallel for detection of several hormones from each class, with comparison of protocols and instrumental parameters. Ultraperformance LC (UPLC®), an emerging technology advertised for reduced retention times, was used in place of HPLC for hormone separation. Applicability to diverse aqueous samples was tested. Matrix interference was combated with two rarely used techniques: atmospheric pressure chemical ionization (APCI) MS2 and extract purification by size exclusion chromatography (SEC). Infusion and spiking tests were performed in (ESI)MS2 and (APCI)MS2, demonstrating relative matrix disruption of hormone signals. An SEC fractionation protocol was developed and applied to extracted wastewater samples prior to UPLC/MS2 analysis. Hormone recoveries were compared to those obtained without SEC purification. In accordance with these experiments, it was found that estrogen and androgen contaminants can be simultaneously extracted using C18 SPE. This approach reduces the amount of sample, supplies, and time required in preparation for instrumental analysis. In UPLC separation, a broader gradient, slower flow rate, and increased run time were used for the androgens to counteract structural similarity and reduced polarity. The androgens were most readily detected using positive (ESI)MS2, versus negative for the estrogens, with modifier addition for signal enhancement. Electron delocalization in the estrogen and testosterone molecular structures facilitated ionization, permitting MS2 detection at or below 23 pg on-column versus 500 pg for the androgens lacking bond conjugation. Recoveries of all analytes from deionized water were 67-112% using UPLC/(ESI)MS2. Use of UPLC reduced retention times and solvent usage in comparison to HPLC, permitting adequate resolution of the hormones within 7 min in the presence of clean solvents. In environmental samples, the rapid analyses proved susceptible to matrix interference, with lack of signal resolution amidst unresolved complex mixtures. The application of (APCI)MS2 to complex samples showed promise in combating matrix interference, permitting detection of hormones spiked into wastewater that were not observed using (ESI)MS2. The ionization methods tended toward opposite matrix effects, with 140-410% recoveries (i.e. ion enhancement) from effluents using APCI and 5-120% (i.e. ion suppression) using ESI. Application of SEC prior to instrumental analysis removed some interfering compounds, allowing recoveries of 48-98% for several hormones using UPLC/(APCI)MS2.

No description available.

This thesis performs simulations of a relay supervisory system (RSS) that works passively in conjunction with the existing protective relaying system at a substation. During normal system operating conditions, the RSS supervises the relay system to prevent trips due to hidden failures. During wide area network disturbances, it adapts the relay system to increase security of the power system. The RSS works passively in the sense that it waits for events to occur in the existing relay system before taking any action. The simulation performed includes a model of the RSS, along with simplified models of existing relays, performed in Matlab. A power system model in EMTP provides inputs to the RSS model. Multiple faults are applied to the EMTP model, and the RSS is tested under each fault condition, and with a variety of relay hidden failures. For all tests performed, the simulation of the RSS successfully prevents relay hidden failure from removing circuit elements inadvertently, while allowing correct relay operations to remove circuit elements. / Master of Science