342 resultados para Speculative attacks
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The makers of Dallas Buyers Club have been dealt a blow in their attempt to extract payment from people alleged to have downloaded illegal copies of the movie. Voltage Pictures, which owns Dallas Buyers Club, has been trying to identify over 4,700 iiNet subscribers who it alleges downloaded illicit copies of the movie. Earlier this year, the Federal Court agreed that iiNet should hand over subscriber details, but warned that any letter sent to account holders must first be approved by the court to protect consumers from abuse of the legal system. In a win for consumer protection, the Federal Court has now rejected Voltage’s draft letters, criticising Voltage’s attempts to avoid explaining what fee it would demand.
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Speculative property developers, criticised for building dog boxes and the slums of tomorrow, are generally hated by urban planners and the public alike. But the doors of state governments are seemingly always open to developers and their lobbyists. Politicians find it hard to say no to the demands of the development industry for concessions because of the contribution housing construction makes to the economic bottom line and because there is a need for well located housing. New supply is also seen as a solution to declining housing affordability. Classical economic theory however is too simplistic for housing supply. Instead, an offshoot of Game Theory - Market Design – not only offers greater insight into apartment supply but also can simultaneously address price, design and quality issues. New research reveals the most significant risk in residential development is settlement risk – when buyers fail to proceed with their purchase despite there being a pre-sale contract. At the point of settlement, the developer has expended all the project funds only to see forecast revenue evaporate. While new buyers may be found, this process is likely to strip the profitability out of the project. As the global financial crisis exposed, buyers are inclined to walk if property values slide. This settlement problem reflects a poor legal mechanism (the pre-sale contract), and a lack of incentive for truthfulness. A second problem is the search costs of finding buyers. At around 10% of project costs, pre-sales are more expensive to developers than finance. This is where Market Design comes in.
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Background: Migraine causes crippling attacks of severe head pain along with associated nausea, vomiting, photophobia and/or phonophobia. The aim of this study was to investigate single nucleotide polymorphisms (SNPs) in the adenosine deaminase, RNA-specific, B1 (ADARB1)and adenosine deaminase, RNA specific, B2 (ADARB2) genes in an Australian case-control Caucasian population for association with migraine. Both candidate genes are highly expressed in the central nervous system (CNS) and fit criteria for migraine neuropathology. SNPs in the ADARB2 gene were previously found to be positively associated with migraine in a pedigree-based GWAS using the genetic isolate of Norfolk Island, Australia. The ADARB1 gene was also chosen for investigation due to its important function in editing neurotransmitter receptor transcripts. Methods: Four SNPs in ADARB1 and nine in ADARB2 were selected by inspecting blocks of LD in Haploview for genotyping using either TaqMan or Sequenom assays. These SNPs were genotyped in two-hundred and ninety one patients who satisfied the International Classification of Headache Disorders, ICHD-II 2004 diagnostic criteria for migraine and three-hundred and fourteen controls and PLINK was used for association testing. Results: Chi-square (χ2) analysis found no significant association between any of the SNPs tested in the ADARB1 and ADARB2 genes in this study and the occurrence of migraine. Conclusions: In contrast to findings that SNPs in the ADARB2 gene were positively associated with migraine in the Norfolk Island population, we find no evidence to support the involvement of RNA editing genes in migraine susceptibility in an Australian Caucasian population.
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Testing the strategies of discourse and materiality, this practice-based and practice-led research experiments with how anonymous storytelling by vulnerable communities, like that of the sexual minorities and their allies in Malaysia, can better speak to their human rights issues without further subjecting them to personal attacks and targetted persecution. The research identifies the critical role of the voice in lending authenticity and credibility to first person narratives; and contextual credibility as a form of credibility which personal stories naturally aspire to achieve with audiences. Adopting a discursive view of persuasion and recognising too that the power of persuasion may in effect lie with those who receive these stories rather than with those who tell them, the insights and knowledge gained from the research informed the development of the field output, Persuasive Storytelling by Vulnerable Communities in Aggressive Contexts: A Human Rights Communication Framework.
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This project analyses and evaluates the integrity assurance mechanisms used in four Authenticated Encryption schemes based on symmetric block ciphers. These schemes are all cross chaining block cipher modes that claim to provide both confidentiality and integrity assurance simultaneously, in one pass over the data. The investigations include assessing the validity of an existing forgery attack on certain schemes, applying the attack approach to other schemes and implementing the attacks to verify claimed probabilities of successful forgeries. For these schemes, the theoretical basis of the attack was developed, the attack algorithm implemented and computer simulations performed for experimental verification.
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We provide the first evidence for interspecific warfare in bees, a spectacular natural phenomenon that involves a series of aerial battles and leads to thousands of fatalities from both attacking and defending colonies. Molecular analysis of fights at a hive of the Australian stingless bee Tetragonula carbonaria revealed that the attack was launched by a related species, Tetragonula hockingsi, which has only recently extended its habitat into southeastern Queensland. Following a succession of attacks by the same T. hockingsi colony over a 4-month period, the defending T. carbonaria colony was defeated and the hive usurped, with the invading colony installing a new queen. We complemented our direct observations with a 5-year study of more than 260 Tetragonula hives and found interspecific hive changes, which were likely to be usurpation events, occurring in 46 hives over this period. We discuss how fighting swarms and hive usurpation fit with theoretical predictions on the evolution of fatal fighting and highlight the many unexplained features of these battles that warrant further study.
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This thesis investigates the use of fusion techniques and mathematical modelling to increase the robustness of iris recognition systems against iris image quality degradation, pupil size changes and partial occlusion. The proposed techniques improve recognition accuracy and enhance security. They can be further developed for better iris recognition in less constrained environments that do not require user cooperation. A framework to analyse the consistency of different regions of the iris is also developed. This can be applied to improve recognition systems using partial iris images, and cancelable biometric signatures or biometric based cryptography for privacy protection.
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Past research has suggested that social engineering poses the most significant security risk. Recent studies have suggested that social networking sites (SNSs) are the most common source of social engineering attacks. The risk of social engineering attacks in SNSs is associated with the difficulty of making accurate judgments regarding source credibility in the virtual environment of SNSs. In this paper, we quantitatively investigate source credibility dimensions in terms of social engineering on Facebook, as well as the source characteristics that influence Facebook users to judge an attacker as credible, therefore making them susceptible to victimization. Moreover, in order to predict users’ susceptibility to social engineering victimization based on their demographics, we investigate the effectiveness of source characteristics on different demographic groups by measuring the consent intentions and behavior responses of users to social engineering requests using a role-play experiment.
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Past research has suggested that social networking sites are the most common source for social engineering-based attacks. Persuasion research shows that people are more likely to obey and accept a message when the source’s presentation appears to be credible. However, many factors can impact the perceived credibility of a source, depending on its type and the characteristics of the environment. Our previous research showed that there are four dimensions of source credibility in terms of social engineering on Facebook: perceived sincerity, perceived competence, perceived attraction, and perceived worthiness. Because the dimensionalities of source credibility as well as their measurement scales can fluctuate from one type of source to another and from one type of context to another, our aim in this study includes validating the existence of those four dimensions toward the credibility of social engineering attackers on Facebook and developing a valid measurement scale for every dimension of them.
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Purpose The purpose of this paper is to identify the financial barriers to the supply of affordable apartments in Australia and examine whether demand aggregation and ‘deliberative development’ (self-build) can form a new affordable housing ‘structure of provision’. Design/methodology/approach Market design, an offshoot of game theory, is used to analyse the existing apartment development model, with ‘deliberative development’ proposed as an innovative alternative. Semi-structured interviews with residential development financiers are used to evaluate whether deliberative development could obtain the requisite development finance. Findings Our investigation into the financial barriers of a deliberative development model suggest that while there are hurdles, these can be addressed if key risks in the exchange process can be mitigated. Hence, affordability can be enhanced by ‘deliberative development’ replacing the existing speculative development model. Research implications Market design is a new innovative theoretical approach to understanding the supply of housing, offering practical solutions to affordable apartment supply in Australia. Originality/value This research identifies financial barriers to the supply of affordable apartments; introduces theoretical understandings gained from market design as an innovative solution; provides evidence that a new structure of building provision based on ‘deliberative development’ could become a key means of achieving more affordable and better designed apartments.
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Background: High-resolution magnetic resonance (MR) imaging has been used for MR imaging-based structural stress analysis of atherosclerotic plaques. The biomechanical stress profile of stable plaques has been observed to differ from that of unstable plaques; however, the role that structural stresses play in determining plaque vulnerability remains speculative. Methods: A total of 61 patients with previous history of symptomatic carotid artery disease underwent carotid plaque MR imaging. Plaque components of the index artery such as fibrous tissue, lipid content and plaque haemorrhage (PH) were delineated and used for finite element analysis-based maximum structural stress (M-C Stress) quantification. These patients were followed up for 2 years. The clinical end point was occurrence of an ischaemic cerebrovascular event. The association of the time to the clinical end point with plaque morphology and M-C Stress was analysed. Results: During a median follow-up duration of 514 days, 20% of patients (n=12) experienced an ischaemic event in the territory of the index carotid artery. Cox regression analysis indicated that M-C Stress (hazard ratio (HR): 12.98 (95% confidence interval (CI): 1.32-26.67, pZ0.02), fibrous cap (FC) disruption (HR: 7.39 (95% CI: 1.61e33.82), p Z 0.009) and PH (HR: 5.85 (95% CI: 1.27e26.77), p Z 0.02) are associated with the development of subsequent cerebrovascular events. Plaques associated with future events had higher M-C Stress than those which had remained asymptomatic (median (interquartile range, IQR): 330 kPa (229e494) vs. 254 kPa (166-290), p Z0.04). Conclusions: High biomechanical structural stresses, in addition to FC rupture and PH, are associated with subsequent cerebrovascular events.
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Atheromatous plaque rupture h the cause of the majority of strokes and heart attacks in the developed world. The role of calcium deposits and their contribution to plaque vulnerability are controversial. Some studies have suggested that calcified plaque tends to be more stable whereas others have suggested the opposite. This study uses a finite element model to evaluate the effect of calcium deposits on the stress within the fibrous cap by varying their location and size. Plaque fibrous cap, lipid pool and calcification were modeled as hyperelastic, Isotropic, (nearly) incompressible materials with different properties for large deformation analysis by assigning time-dependent pressure loading on the lumen wall. The stress and strain contours were illustrated for each condition for comparison. Von Mises stress only increases up to 1.5% when varying the location of calcification in the lipid pool distant to the fibrous cap. Calcification in the fibrous cap leads to a 43% increase of Von Mises stress when compared with that in the lipid pool. An increase of 100% of calcification area leads to a 15% stress increase in the fibrous cap. Calcification in the lipid pool does not increase fibrous cap stress when it is distant to the fibrous cap, whilst large areas of calcification close to or in the fibrous cap may lead to a high stress concentration within the fibrous cap, which may cause plaque rupture. This study highlights the application of a computational model on a simulation of clinical problems, and it may provide insights into the mechanism of plaque rupture.
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Underground tunnels are vulnerable to terrorist attacks which can cause collapse of the tunnel structures or at least extensive damage, requiring lengthy repairs. This paper treats the blast impact on a reinforced concrete segmental tunnel buried in soil under a number of parametric conditions; soil properties, soil cover, distance of explosive from the tunnel centreline and explosive weight and analyses the possible failure patterns. A fully coupled Fluid Structure Interaction (FSI) technique incorporating the Arbitrary Lagrangian-Eulerian (ALE) method is used in this study. Results indicate that the tunnel in saturated soil is more vulnerable to severe damage than that buried in either partially saturated soil or dry soil. The tunnel is also more vulnerable to surface explosions which occur directly above the centre of the tunnel than those that occur at any equivalent distances in the ground away from the tunnel centre. The research findings provide useful information on modeling, analysis, overall tunnel response and failure patterns of segmented tunnels subjected to blast loads. This information will guide future development and application of research in this field.
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Secure communication channels are typically constructed from an authenticated key exchange (AKE) protocol, which authenticates the communicating parties and establishes shared secret keys, and a secure data transmission layer, which uses the secret keys to encrypt data. We address the partial leakage of communicating parties' long-term secret keys due to various side-channel attacks, and the partial leakage of plaintext due to data compression. Both issues can negatively affect the security of channel establishment and data transmission. In this work, we advance the modelling of security for AKE protocols by considering more granular partial leakage of parties' long-term secrets. We present generic and concrete constructions of two-pass leakage-resilient key exchange protocols that are secure in the proposed security models. We also examine two techniques--heuristic separation of secrets and fixed-dictionary compression--for enabling compression while protecting high-value secrets.
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Security models for two-party authenticated key exchange (AKE) protocols have developed over time to capture the security of AKE protocols even when the adversary learns certain secret values. Increased granularity of security can be modelled by considering partial leakage of secrets in the manner of models for leakage-resilient cryptography, designed to capture side-channel attacks. In this work, we use the strongest known partial-leakage-based security model for key exchange protocols, namely continuous after-the-fact leakage eCK (CAFL-eCK) model. We resolve an open problem by constructing the first concrete two-pass leakage-resilient key exchange protocol that is secure in the CAFL-eCK model.