329 research outputs found

    Modeling and verification of insider threats using logical analysis

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    In this paper we combine formal modeling and analysis of infrastructures of organisations with sociological explanation to provide a framework for insider threat analysis. We use the Higher Order Logic proof assistant Isabelle/HOL to support this framework. In the formal model, we exhibit and use a common trick from the formal verification of security protocols showing that it is applicable to insider threats. We introduce briefly a three step process of social explanation illustrating that it can be applied fruitfully to the characterisation of insider threats. We introduce the Insider theory constructed in Isabelle that implements this process of social explanation. To validate that the social explanation is generally useful for the analysis of insider threats and to demonstrate our framework, we model and verify the insider threat patterns Entitled Independent and Ambitious Leader in our Isabelle/HOL framework

    Reduction of slaughterhouse stress in beef cattle by facilitating animal tameness

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    The relationship between animals and humans is important for animal husbandry and welfare. Loosehousing and grazing systems with low management input often result in frail relationships between humans and animals. This study investigated whether a positive handling, applied during the first days of the animals’ life, had a calming and stress reducing effect on suckler beef calves at slaughter

    Learning Multiple Defaults for Machine Learning Algorithms

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    The performance of modern machine learning methods highly depends on their hyperparameter configurations. One simple way of selecting a configuration is to use default settings, often proposed along with the publication and implementation of a new algorithm. Those default values are usually chosen in an ad-hoc manner to work good enough on a wide variety of datasets. To address this problem, different automatic hyperparameter configuration algorithms have been proposed, which select an optimal configuration per dataset. This principled approach usually improves performance, but adds additional algorithmic complexity and computational costs to the training procedure. As an alternative to this, we propose learning a set of complementary default values from a large database of prior empirical results. Selecting an appropriate configuration on a new dataset then requires only a simple, efficient and embarrassingly parallel search over this set. We demonstrate the effectiveness and efficiency of the approach we propose in comparison to random search and Bayesian Optimization

    Qualité de la viande d’agneau de quatre races ovines suisses

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    La qualité de la viande des agneaux de boucherie dépend d’un grand nombre de facteurs. Outre l’âge au moment de l’abattage et le sexe, l’affouragement a une incidence prépondérante. En principe, un affouragement constitué principalement de céréales, comparé à du fourrage plutôt grossier, provoque les plus grandes différences dans la qualité de la viande. Une autre influence très discutée sur la qualité de la viande est la race; on dit que les races primitives comme le Heidschnucke ont une qualité de viande élevée, se rapprochant de celle du gibier. Certaines races primitives suisses ont également la réputation d’avoir une viande particulièrement bonne. Cet article traite de la question de savoir si la viande d’agneau des races Nez Noir du Valais, Blancs des Alpes, mouton de l’Engadine et mouton Miroir se distingue au niveau de la qualité

    Towards formal analysis of insider threats for auctions

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    This paper brings together the world of insider threats and auctions. For online-auction systems, like eBay, but also for high-value one-off auction algorithms as they are used for selling radio wave frequencies, the use of rigorous machine supported modelling and verification techniques is meaningful to prove correctness and scrutinize vulnerability to security and privacy attacks. Surveying the threats in auctions and insider collusions, we present an approach to model and analyze auction protocols for insider threats using the interactive theorem prover Isabelle. As a case study, we use the cocaine auction protocol that represents a nice combination of cryptographic techniques, protocols, and privacy goals suitable for highlighting insider threats for auctions

    Insider threats for auctions: formalization, mechanized proof, and code generation

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    This paper applies machine assisted formal methods to explore insider threats for auctions. Auction systems, like eBay, are an important problem domain for formal analysis because they challenge modelling concepts as well as analysis methods. We use machine assisted formal modelling and proof in Isabelle to demonstrate how security and privacy goals of auction protocols can be formally verified. Applying the costly scrutiny of formal methods is justified for auctions since privacy and trust are prominent issues and auctions are sometimes designed for one-off occasions where high bids are at stake. For example, when radio wave frequencies are on sale, auctions are especially created for just one occasion where fair and consistent behaviour is required. Investigating the threats in auctions and insider collusions, we model and analyze auction protocols for insider threats using the interactive theorem prover Isabelle. We use the existing example of a fictitious cocaine auction protocol from the literature to develop and illustrate our approach. Combining the Isabelle Insider framework with the inductive approach to verifying security protocols in Isabelle, we formalize the cocaine auction protocol, prove that this formal definition excludes sweetheart deals, and also that collusion attacks cannot generally be excluded. The practical implication of the formalization is demonstrated by code generation. Isabelle allows generating code from constructive specifications into the programming language Scala. We provide constructive test functions for cocaine auction traces, prove within Isabelle that these functions conform to the protocol definition, and apply code generation to produce an implementation of the executable test predicate for cocaine auction traces in Scala

    Lammfleischqualität von extensiv gehaltenen und seltenen Schweizer Schafrassen (Engadinerschaf, Schwarznasenschaf, Spiegelschaf) im Vergleich zum Weißen Alpenschaf

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    This study investigates meat quality of four autochthonous Swiss ovine breeds, White Alpine (WAS, n=15), Walliser blacknose sheep (SN, n=8), Engadine sheep (EN, n=9) and the Mirror sheep (SP, n=10). Especially for the latter two breeds, which are rare and endangered, information about meat quality and constitution is important for merchandising issues. All lambs (LW 20-25 kg) of each breed were fattened on pasture for 208 d and subsequently slaughtered. Evaluations were carried out for slaughter yield and classifications, pH-value, colorimetry (L*a*b*-System), shear force (Warner Bratzler method) and cooking losses in the Musculus longissimus dorsi. The results showed no meat quality defects in any breed. The main differences between breeds arose in slaughter yield (p<0.001) with SN being significantly inferior to WAS, and CHTAX where WAS was clearly superior to all other breeds. Compared to WAS, SN meat was less colored (L*-value; p<0.001) which is probably related to the higher pH24h (p<0.01) of SN when compared to WAS. Overall, this study showed that meat quality of WAS is superior with low-land pasture based fattening conditions in Switzerland. It is however possible that other fattening conditions (i.e. mountainous) would lead to different results because Black nose, Engadine and Mirror sheep are traditional alpine breeds which might substantially alter their production optimum

    Lammfleischqualität von vier Schweizer Schafrassen

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    Die Fleischqualität von Schlachtlämmern wird von einer Vielzahl von Faktoren bestimmt. Neben dem Schlachtalter und dem Geschlecht hat v.a. die Fütterung einen grossen Einfluss auf die Fleischqualität. Grundsätzlich führt eine getreidelastige im Vergleich zu einer rauhfutterlastigen Fütterung zu den grössten Unterschieden in der Fleischqualität. Ein weiterer viel diskutierter Einfluss auf die Fleischqualität ist die Rasse. Beispielsweise wird ursprünglichen Rassen, wie z.B. der Heidschnucke, eine besonders hohe Fleischqualität nachgesagt, die sich auch in einem besonderen wildbretartigen Geschmack zeigen soll. Auch in der Schweiz wird gewissen ursprünglichen Rassen eine speziell gute Fleischqualität zugesprochen. Dieser Artikel befasst sich mit der Frage, ob das Lammfleisch der Rassen Walliser Schwarznasenschaf, Weisses Alpenschaf, Engadiner- und Spiegelschaf qualitativ unterschiedlich ist
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