111 resultados para DDoS attack discrimination


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Nociception allows for immediate reflex withdrawal whereas pain allows for longer-term protection via rapid learning. We examine here whether shore crabs placed within a brightly lit chamber learn to avoid one of two dark shelters when that shelter consistently results in shock. Crabs were randomly selected to receive shock or not prior to making their first choice and were tested again over 10 trials. Those that received shock in trial 2, irrespective of shock in trial 1, were more likely to switch shelter choice in the next trial and thus showed rapid discrimination. During trial 1, many crabs emerged from the shock shelter and an increasing proportion emerged in later trials, thus avoiding shock by entering a normally avoided light area. In a final test we switched distinctive visual stimuli positioned above each shelter and/or changed the orientation of the crab when placed in the chamber for the test. The visual stimuli had no effect on choice, but crabs with altered orientation now selected the shock shelter, indicating that they had discriminated between the two shelters on the basis of movement direction. These data, and those of other recent experiments, are consistent with key criteria for pain experience and are broadly similar to those from vertebrate studies. © 2013. Published by The Company of Biologists Ltd.

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Chiral thioureas and functionalised chiral thiouronium salts were synthesised starting from the relatively cheap and easily available chiral amines: (S)-methylbenzylamine and rosin-derived (+)-dehydroabietylamine. The introduction of a delocalised positive charge to the thiourea functionality, by an alkylation reaction at the sulfur atom, enables dynamic rotameric processes: hindered rotations about the delocalised CN and CS bonds. Hence, four different rotamers/isomers may be recognised: syn-syn, syn-anti, anti-syn and anti-anti. Extensive H-1 and C-13 NMR studies have shown that in hydrogen-bond acceptor solvents, such as perdeuteriated dimethyl sulfoxide, the syn-syn conformation is preferable. On the other hand, when using non-polar solvents, such as CDCl3, the mixture of syn-syn and syn-anti isomers is detectable, with an excess of the latter. Apart from this, in the case of S-butyl-N,N'-bis(dehydroabietyl)thiouronium ethanoate in CDCl3, the H-1 NMR spectrum revealed that strong bifurcated hydrogen bonding between the anion and the cation causes global rigidity without signs of hindered rotamerism observable on the NMR time scale. This suggested that these new salts might be used as NMR discriminating agents for chiral oxoanions, and are indeed more effective than their archetypal guanidinium analogues or the neutral thioureas. The best results in recognition of a model substrate, mandelate, were obtained with S-butyl-N,N'-bis(dehydroabietyl) thiouronium bistriflamide. It was confirmed that the chiral recognition occurred not only for carboxylates but also for sulfonates and phosphonates. Further H-1 NMR studies confirmed a 1 : 1 recognition mode between the chiral agent (host) and the substrate (guest); binding constants were determined by H-1 NMR titrations in solutions of DMSO-d(6) in CDCl3. It was also found that the anion of the thiouronium salt had a significant influence on the recognition process: anions with poor hydrogen-bond acceptor abilities led to the best discrimination. The presence of host-guest hydrogen bonding was confirmed in the X-ray crystal structure of S-butyl-N,N'-bis(dehydroabietyl)thiouronium bromide and by computational studies (density functional theory).

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DeAuthentication Denial of Service attacks in Public Access WiFi operate by exploiting the lack of authentication of management frames in the 802.11 protocol. Detection of these attacks rely almost exclusively on the selection of appropriate thresholds. In this work the authors demonstrate that there are additional, previously unconsidered, metrics which also influence DoS detection performance. A method of systematically tuning these metrics to optimal values is proposed which ensures that parameter choices are repeatable and verifiable.

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We consider the problem of self-healing in peer-to-peer networks that are under repeated attack by an omniscient adversary. We assume that, over a sequence of rounds, an adversary either inserts a node with arbitrary connections or deletes an arbitrary node from the network. The network responds to each such change by quick “repairs,” which consist of adding or deleting a small number of edges. These repairs essentially preserve closeness of nodes after adversarial deletions, without increasing node degrees by too much, in the following sense. At any point in the algorithm, nodes v and w whose distance would have been l in the graph formed by considering only the adversarial insertions (not the adversarial deletions), will be at distance at most l log n in the actual graph, where n is the total number of vertices seen so far. Similarly, at any point, a node v whose degree would have been d in the graph with adversarial insertions only, will have degree at most 3d in the actual graph. Our distributed data structure, which we call the Forgiving Graph, has low latency and bandwidth requirements. The Forgiving Graph improves on the Forgiving Tree distributed data structure from Hayes et al. (2008) in the following ways: 1) it ensures low stretch over all pairs of nodes, while the Forgiving Tree only ensures low diameter increase; 2) it handles both node insertions and deletions, while the Forgiving Tree only handles deletions; 3) it requires only a very simple and minimal initialization phase, while the Forgiving Tree initially requires construction of a spanning tree of the network.

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The increased complexity and interconnectivity of Supervisory Control and Data Acquisition (SCADA) systems in the Smart Grid has exposed them to a wide range of cyber-security issues, and there are a multitude of potential access points for cyber attackers. This paper presents a SCADA-specific cyber-security test-bed which contains SCADA software and communication infrastructure. This test-bed is used to investigate an Address Resolution Protocol (ARP) spoofing based man-in-the-middle attack. Finally, the paper proposes a future work plan which focuses on applying intrusion detection and prevention technology to address cyber-security issues in SCADA systems.

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We consider the problem of self-healing in peer-to-peer networks that are under repeated attack by an omniscient adversary. We assume that, over a sequence of rounds, an adversary either inserts a node with arbitrary connections or deletes an arbitrary node from the network. The network responds to each such change by quick "repairs," which consist of adding or deleting a small number of edges. These repairs essentially preserve closeness of nodes after adversarial deletions,without increasing node degrees by too much, in the following sense. At any point in the algorithm, nodes v and w whose distance would have been - in the graph formed by considering only the adversarial insertions (not the adversarial deletions), will be at distance at most - log n in the actual graph, where n is the total number of vertices seen so far. Similarly, at any point, a node v whose degreewould have been d in the graph with adversarial insertions only, will have degree at most 3d in the actual graph. Our distributed data structure, which we call the Forgiving Graph, has low latency and bandwidth requirements. The Forgiving Graph improves on the Forgiving Tree distributed data structure from Hayes et al. (2008) in the following ways: 1) it ensures low stretch over all pairs of nodes, while the Forgiving Tree only ensures low diameter increase; 2) it handles both node insertions and deletions, while the Forgiving Tree only handles deletions; 3) it requires only a very simple and minimal initialization phase, while the Forgiving Tree initially requires construction of a spanning tree of the network. © Springer-Verlag 2012.

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Rural communities in the Haut-Uele Province of northern Democratic Republic of Congo live in constant danger of attack and/or abduction by units of the Lord's Resistance Army operating in the region. This pilot study sought to develop and evaluate a community-participative psychosocial intervention involving life skills and relaxation training and Mobile Cinema screenings with this war-affected population living under current threat. 159 war-affected children and young people (aged 7-18) from the villages of Kiliwa and Li-May in north-eastern DR Congo took part in this study. In total, 22% of participants had been abduction previously while 73% had a family member abducted. Symptoms of post-traumatic stress reactions, internalising problems, conduct problems and pro-social behaviour were assessed by blinded interviewers at pre- and post-intervention and at 3-month follow-up. Participants were randomised (with an accompanying caregiver) to 8 sessions of a group-based, community-participative, psychosocial intervention (n=79) carried out by supervised local, lay facilitators or a wait-list control group (n=80). Average seminar attendance rates were high: 88% for participants and 84% for caregivers. Drop-out was low: 97% of participants were assessed at post-intervention and 88% at 3 month follow-up. At post-test, participants reported significantly fewer symptoms of post-traumatic stress reactions compared to controls (Cohen's d=0.40). At 3 month follow up, large improvements in internalising symptoms and moderate improvements in pro-social scores were reported, with caregivers noting a moderate to large decline in conduct problems among the young people. Trial Registration clinicalTrials.gov, Identifier: NCT01542398.

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In this short paper, we present an integrated approach to detecting and mitigating cyber-attacks to modern interconnected industrial control systems. One of the primary goals of this approach is that it is cost effective, and thus whenever possible it builds on open-source security technologies and open standards, which are complemented with novel security solutions that address the specific challenges of securing critical infrastructures.

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A new Icelandic ash layer has been detected in mid-Interstadial sediments in a number of Scottish Lateglacial sequences and has been named the Penifiler Tephra. It is rhyolitic in composition and possesses a chemistry, which is similar to the Borrobol Tephra of early Lateglacial Interstadial age, which also occurs in a number of these same sequences. Where the Borrobol Tephra has been identified in these sequences it consistently exhibits a diffuse distribution accompanied in some cases by stratigraphic bimodality. A number of sedimentological and taphonomic factors are considered in order to account for this distribution. One possibility is that these distributions are produced by taphonomic factors. Another possibility is that the Borrobol Tephra may not be the product of a single Icelandic eruption, but of two events closely spaced in time. In at least two of the sequences investigated in this study, basaltic shards were found in association with the Penifiler and Borrobol tephras, suggesting either a basaltic phase associated with these eruptions, or coincident eruptions from a separate basaltic volcanic centre. The discovery of the new Penifiler Tephra makes a contribution to the regional tephrostratigraphic framework, and provides an additional isochron for assessing the synchroneity of palaeoenvironmental changes during the Interstadial. The true stratigraphic nature and age of the Borrobol Tephra, however, remains unresolved and, therefore, its use as an isochron is more problematic. The possible occurrence of basaltic populations may strengthen correlations with basaltic tephras recently detected in the NGRIP ice-core.

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Although only addressed by EU law from 2000, age discrimination has been the theme of quite a few cases before the Court of Justice, with a high proportion decided by the Grand Chamber recently. This is due to the conceptual and theoretical challenges that a prohibition to use age as differentiating factor poses. After all, age has been an important stratifier used to synchronize life courses through welfare State regimes in Europe. Partly due to these traditions, there are stereotypes associated with old age, and young age, that in turn lead to disadvantage in employment. For the same reason, age discrimination frequently intersects with discrimination on other grounds, such as sex, race or disability. EU legislation on age discrimination has sought to accommodate the traditional role of age in employment policy by allowing wider justifications than for other forms of discrimination. This leads to contradictions within the larger field of discrimination law, which may even threaten to dilute its efficiency. This article analyses how recent case law of the Court of Justice, and in particular its Grand Chamber, deals with the theoretical challenges posed by these conflicting demands on age discrimination and on discrimination law at large.

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Context Medical students can have difficulty in distinguishing left from right. Many infamous medical errors have occurred when a procedure has been performed on the wrong side, such as in the removal of the wrong kidney. Clinicians encounter many distractions during their work. There is limited information on how these affect performance. 
Objectives Using a neuropsychological paradigm, we aim to elucidate the impacts of different types of distraction on left–right (LR) discrimination ability. 
Methods Medical students were recruited to a study with four arms: (i) control arm (no distraction); (ii) auditory distraction arm (continuous ambient ward noise); (iii) cognitive distraction arm (interruptions with clinical cognitive tasks), and (iv) auditory and cognitive distraction arm. Participants’ LR discrimination ability was measured using the validated Bergen Left–Right Discrimination Test (BLRDT). Multivariate analysis of variance was used to analyse the impacts of the different forms of distraction on participants’ performance on the BLRDT. Additional analyses looked at effects of demographics on performance and correlated participants’ self-perceived LR discrimination ability and their actual performance. 
Results A total of 234 students were recruited. Cognitive distraction had a greater negative impact on BLRDT performance than auditory distraction. Combined auditory and cognitive distraction had a negative impact on performance, but only in the most difficult LR task was this negative impact found to be significantly greater than that of cognitive distraction alone. There was a significant medium-sized correlation between perceived LR discrimination ability and actual overall BLRDT performance. 
Conclusions
Distraction has a significant impact on performance and multifaceted approaches are required to reduce LR errors. Educationally, greater emphasis on the linking of theory and clinical application is required to support patient safety and human factor training in medical school curricula. Distraction has the potential to impair an individual's ability to make accurate LR decisions and students should be trained from undergraduate level to be mindful of this.

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This book contributes to a critical reflection of current legislative and jurisprudential developments in Non-Discrimination Law, focusing on the European Union. The book is focused on intersectionality between gender, race and disability and the question of whether, and to what extent, this intersection can be adequately addressed in (EU) law. The discussion rests on two basic assumptions. First, the multiplication of 'discrimination grounds' in EU law and other legal regimes should not result in a dilution of the demands of equality law. Accordingly, the book focuses on the three key grounds - race, gender and disability. These constitute nodes around which other discrimination grounds can be grouped. Second, any multi-ground non-discrimination law framework needs to engage with the question of discrimination on several grounds. This book provides a critical evaluation of some of the problems presented by such intersectionality and an opportunity to explore the issues in depth. This collection offers some new proposals relating to the regrouping of identity categories and to the general approach to socio-legal research in the field. It also contains a comparative section, which expands on practical experiences with intersectionality and law, and a section dedicated to juridical responses to intersectionality.

The book will be a valuable resource for researchers, academics and those working in the area of EU non-discrimination law and policy.

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EU non-discrimination law has seen a proliferation of discrimination grounds from 2000. Dis-crimination on grounds of gender (in the field of equal pay) and on grounds of nationality (generally within the scope of application of EU law) were the only prohibited forms of discrimination in EU law, until the Treaty of Amsterdam empowered the Community to legislate in order to combat discrimination on grounds of sex, racial or ethnic origin, religion or belief, disability, age or sexual orientation (Article 13 EC). Proliferation of non-discrimination grounds is also characteristic for international and national non-discrimination law. As such, proliferation of grounds results in an increase in potential cases of “multiple discrimination” and the danger of diluting the demands of equality law by ever more multiplication of grounds. The hierarchy of equality, which has been so widely criticised in EU law, is a signifier of the latter danger.
This chapter proposes to structure the confusing field of non-discrimination grounds by organising them around nodes of discrimination fields. It will first reflect different ways of establishing hierarchies between grounds. This will be followed by a recount of different (narrow and wide) reading of grounds. A comprehensive reading of the grounds gender, ‘race’ and disability as establishing overlapping fields of discrimination grounds will be mapped out, with some examples for practical uses.