Supervisory control and data acquisition systems are extensively used in the critical infrastructure domain for controlling and managing large-scale industrial applications. This thesis presents a security management structure developed to protect ICS networks from security intrusions. This structure is formed by a combination of several modules for monitoring system-utilization parameters, data processing, detection of known attacks, forensic analysis to support against unknown attacks, estimation of control system-specific variables, and launch of appropriate protection methods. The best protection method to launch in case of an attack is chosen by a multi-criteria analysis controller based on operational costs and efficiency. A time-series ARIMA model is utilized to estimate the future state of the system and to protect it against cyber intrusions. Signature and performance based detection techniques assist in real-time identification of attacks with little or no human intervention. Simulation results for Scanning, Denial of Service and Injection attacks are provided.

Research supports the notion that sexual and physical assault history is associated with the use of self-protective strategies. One shortcoming in this area of research is the reliance on dichotomous (yes-no) measures of assault as opposed to number of experiences. The aim of this study was to determine if the number of sexual and physical assaults experienced is associated with self-protection behaviors, controlling for general safety concerns. Women (N = 293) completed measures of sexual and physical assault, self-protective behaviors, fear, and safety concerns using a web based survey. Contrary to expectations, sexual and physical assault (and the interactive effect of these variables) were not related to self-protective behaviors. However, safety concerns and overall fear were positively associated with the use of self-protective behaviors. These findings have implications for the creation of interventions aimed at victims of crime.

When people are asked to compare themselves to others, they frequently engage in self-enhancement. Further, prior work has shown that when engaging in self-enhancement, people tend to downplay how often they engage in negative behaviors to a greater extent than they highlight how often they engage in positive behaviors. Interestingly, the opposite pattern is shown for traits: people highlight their positive traits to a greater extent than they downplay their negative traits. In the current work, we examined direct and indirect social comparisons for sets of health, eating, social, and moral dimensions. Across our first 7 studies, we demonstrated that people downplayed negative aspects of the self to a greater extent than they highlighted positive aspects of the self when the aspect was not self-relevant, while people showed little to no preference for downplaying negative aspects of the self relative to highlighting positive aspects of the self when the aspect was self-relevant. In Study 8, we demonstrated that this pattern is partially mediated by recall of feedback about the average other student, but not by recall of one’s self-standing. Together these findings integrate the different patterns of self-enhancement shown for behaviors and traits by demonstrating that differences in the self-relevance of the dimension may be the best cue as to whether people are most likely to self-enhance by downplaying negatives or emphasizing positives. / 10000-01-01

Today’s software landscape features a high degree of complexity, frequent changes in requirements and stakeholder goals, and uncertainty. Uncertainty and high complexity imply a threat landscape where cybersecurity attacks are a common occurrence, while their consequences are often severe. Self-adaptive systems have been proposed to mitigate the complexity and frequent degree of change by adapting at run-time to deal with situations not known at design time. They, however, are not immune to attacks, as they themselves suffer from high degrees of complexity and uncertainty. Therefore, systems that can dynamically defend themselves from adversaries are required. Such systems are called self-protecting systems and aim to identify, analyse and mitigate threats autonomously. This thesis contributes two approaches towards the goal of providing systems with self-protection capabilities. The first approach aims to enhance the security of architecture-based selfadaptive systems and equip them with (proactive) self-protection capabilities that reduce the exposed attack surface. We target systems where information about the system components and its adaptation decisions is available, and control over its adaptation is also possible. We formally model the security of the system and provide two methods to analyze its security that help us rank adaptations in terms of their security level: a method based on quantitative risk assessment and a method based on probabilistic verification. The results indicate an improvement to the system security when either of our solutions is employed. However, only the second method can provide self-protecting capabilities. We have identified a direct relationship between security and performance overhead, i.e., higher security guarantees impose analogously higher performance overhead. The second approach targets open decentralized systems where we have limited information about and control over the system entities. Therefore, we attempt to employ decentralized information flow control mechanisms to enforce security by controlling interactions among the system elements. We extend a classical decentralized information flow control model by incorporating trust and adding adaptation capabilities that allow the system to identify security threats and self-organize to maximize the average trust between the system entities. We arrange entities of the system in trust hierarchies that enforce security policies among their elements and can mitigate security issues raised by the openness and uncertainty in the context and environment, without the need for a trusted central controller. The experiment results show that a reasonable level of trust can be achieved and at the same time confidentiality and integrity can be enforced with a low impact on the throughput and latency of messages exchanged in the system.

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[pt] O direito de retenção é a faculdade assegurada ao credor de uma relação jurídica de reter uma coisa a outrem devida até a satisfação de um crédito ao qual faz jus em decorrência de benfeitorias nela introduzidas. Em outras palavras, trata-se de uma causa legítima para a recusa da restituição da coisa ao seu legítimo titular, com o consequente prolongamento da posse para além do momento em que deveria cessar. Todavia, a temática é objeto de tratamento assistemático e desconexo no direito brasileiro, com resquícios da tipificação criminal do uso arbitrário das próprias razões. Propõe-se, portanto, um exame do instituto tendo o artigo 1.219 do Código Civil como a base principiológica, sobretudo com relação à subjetividade da boa-fé indicada pelo legislador, buscando-se identificar a possibilidade de aplicabilidade do instituto para além dos formalismos apriorísticos e dogmatismos históricos e como forma de autotutela. / [en] The right of retention is the faculty granted to the creditor of a legal relationship to retain something owed to its rightful owner until the satisfaction of a credit due to improvements introduced therein. In other words, it is a legitimate reason of refusal of return the thing to its rightful owner, with the consequent prolongation of possession beyond the moment that should cease. However, the matter is subject to unsystematic and disjointed treatment in Brazilian law, with traces of the criminal typification of arbitrary use of own reasons. Therefore, an examination of the institute is proposed, with Article 1,219 of the Brazilian Civil Code as the principled basis, specially related to the subjectivity of good faith indicated by the legislator, seeking to identify the possibility of applying the institute beyond aprioristic formalisms and historical dogmatisms and as and as a self-protection form.

The present study aims to contribute to insurance sector by investigating the risk reduction mechanisms: self-insurance, self-protection, and market insurance. First, individual valuations/demands for these mechanisms in fire and earthquake events are analyzed through conducting an experiment to 78 students from Middle East Technical University In addition, the effects of risk attitude, personality traits, and demographic variables (that are measured through using a questionnaire) on valuations to these precautionary actions&rsquo / are examined. The findings show that, consistent with the theory, self-insurance and market insurance are substitutes to each other / contrary to the theory, self-protection and market insurance are not complements, they are also substitutes to each other. Further, individuals prefer self-protection and self-insurance to market insurance for both fire and earthquake events. Lastly, individual investment attitude is found to affect the valuations of these three risk reduction mechanisms positively concluding that people perceive these mechanisms as an investment tool.

We re-examine the classic problem of risk aversion and self-protection in this paper. In the beginning of this paper, we conduct comparative statics of risk aversion and prevention efforts based on the mono-periodic two states model of choice under risk. We show this new condition is effective with self-insurance-cum-protection model (Lee, 1998), in which the decision maker's activities to prevent the risk can sever both as self-insurance and self-protection. We suggest a new condition that increased risk aversion induces more prevention activities. This new condition requires only one assumption concerning fear of ruin coefficient, marginal effect of SICP activity on probability and marginal cost of SICP activity. By applying interval dominance order (Quah and Strulovici,2009), we find that a decision maker will exert higher level of SICP activity if he becomes more risk averse, under the condition that his hazard rate is higher than the 'boldness' coefficient (Aumann and Kurz,1977). This new condition is effective even when the optimal level for SICP activity is not interior solution. With our method, the assumption, that optimal solution is interior, is not necessary and marginal utility functions do not need to be monotonic on the interval [0, w0]. Based on this, the optimal solution can be corner solution or inflection point solution. And the DM's attitude towards risk can be variable. Hence, the relation suggested by our findings is more consistent with real world situations.

No description available.

No description available.