77,449 research outputs found

    Optimal Scanning Bandwidth Strategy Incorporating Uncertainty about Adversary's Characteristics

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    In this paper we investigate the problem of designing a spectrum scanning strategy to detect an intelligent Invader who wants to utilize spectrum undetected for his/her unapproved purposes. To deal with this problem we model the situation as two games, between a Scanner and an Invader, and solve them sequentially. The first game is formulated to design the optimal (in maxmin sense) scanning algorithm, while the second one allows one to find the optimal values of the parameters for the algorithm depending on parameters of the network. These games provide solutions for two dilemmas that the rivals face. The Invader's dilemma consists of the following: the more bandwidth the Invader attempts to use leads to a larger payoff if he is not detected, but at the same time also increases the probability of being detected and thus fined. Similarly, the Scanner faces a dilemma: the wider the bandwidth scanned, the higher the probability of detecting the Invader, but at the expense of increasing the cost of building the scanning system. The equilibrium strategies are found explicitly and reveal interesting properties. In particular, we have found a discontinuous dependence of the equilibrium strategies on the network parameters, fine and the type of the Invader's award. This discontinuity of the fine means that the network provider has to take into account a human/social factor since some threshold values of fine could be very sensible for the Invader, while in other situations simply increasing the fine has minimal deterrence impact. Also we show how incomplete information about the Invader's technical characteristics and reward (e.g. motivated by using different type of application, say, video-streaming or downloading files) can be incorporated into scanning strategy to increase its efficiency.Comment: This is the last draft version of the paper. Revised version of the paper was published in EAI Endorsed Transactions on Mobile Communications and Applications, Vol. 14, Issue 5, 2014, doi=10.4108/mca.2.5.e6. arXiv admin note: substantial text overlap with arXiv:1310.724

    Policing organized crime : a new direction

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    Recent criminological research in the Netherlands underscores the fact that organized crime is embedded in society and the overall picture makes it clear that police emphasis on a crime fighting model of the police, based solely on criminal law will not be entirely effective. Therefore, the Twente police force developed a new strategy of policing organized crime in their region. This strategy is based on criminological knowledge and on the approach of community policing: preventive, pro-active and integrated actions taken by various partners of the police in order to reduce illegal activities of organized crime groups. This strategy, however, can only succeed when two conditions are satisfied. First, this approach can only function in an open democratic society in which numerous public and private organizations and the public feel responsible for the emergence of organized crime in their environment. Secondly, the police force and their partners must be (relatively) free of corruption. This implies that this strategy can only be effective in societies in which organized crime has not deeply penetrated democratic institutions and business organizations

    Key factor for hastening the strategic issue diagnosis process: a within organisational model

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    Previous research on Strategic Issue Diagnosis (SID) had focused on the complexity and novelty associated with the decision-making process in a turbulent environment. What had not been previously addressed in the extant literature is the requirement for speed inherent within the SID process, especially that is related to the gathering of information and facts through an organisation’s environmental scanning procedures. Since proactive management techniques, nimble processes, and systems that allow an organisation to be responsive and build rapid decision-making capabilities are important determinants of success in a turbulent environment, the element of speed associated with SID is an important factor. Our paper identifi es a series of propositions focusing att ention on elements of the environmental scanning processes and management hierarchies that are intended to counteract the recursiveness and redundancy inherent in SID systems and ultimately hasten the strategic decision-making process

    Cosmic microwave background anisotropy power spectrum statistics for high precision cosmology

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    As the era of high precision cosmology approaches, the empirically determined power spectrum of the microwave background anisotropy, ClC_l, will provide a crucial test for cosmological theories. We present a unified semi-analytic framework for the study of the statistical properties of the ClC_l coefficients computed from the results of balloon, ground based, and satellite experiments. An illustrative application shows that commonly used approximations {\it bias} the estimation of the baryon parameter Ωb\Omega_b at the 1% level even for a satellite capturing as much as ∼70\sim 70% of the sky.Comment: 4 pages, 3 figures. Also available at http://www.tac.dk/~wandelt/downloads.htm

    The impact of mass media interventions on tuberculosis awareness, health-seeking behaviour and health service utilisation : a systematic review protocol

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    Introduction: Tuberculosis (TB) is a serious public health problem in many parts of the world. Strategies to curb the spread of TB must match the multifaceted nature of the epidemic. The use of mass media is one of the important strategies in communicating behavioural change in relation to TB prevention and the treatment. However, the benefits of this intervention are unclear. We, therefore, plan to conduct a systematic review on the effects of mass media interventions on TB awareness, health-seeking behaviour and health service utilisation. Methods and analysis: We will preferably include randomised controlled trials (RCTs) in this systematic review. However, non-randomised studies will be included if there is an inadequate number of RCTs. We will perform electronic searches in PubMed, Scopus and other databases, along with manual searches. Articles written (or translated) in English and French and published between 1 January 1980 and 31 October 2013 will be eligible for inclusion in this review. The primary outcomes will be TB knowledge, attitudes and awareness, healthcare-seeking behaviour and service utilisation. The secondary outcomes will include stigma and discrimination against people with TB and the costs of the interventions. We will investigate clinical and statistical heterogeneity and pool studies judged to be clinically and statistically homogeneous. Relative risks will be calculated for dichotomous outcomes and mean differences for continuous outcomes, both with their corresponding 95% CIs. Ethics and dissemination: The systematic review will use data that is not linked to individuals. The review findings may have implications for clinical practice and future research, and will be disseminated electronically and in print through peer-reviewed publications

    Planck pre-launch status: High Frequency Instrument polarization calibration

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    The High Frequency Instrument of Planck will map the entire sky in the millimeter and sub-millimeter domain from 100 to 857 GHz with unprecedented sensitivity to polarization (ΔP/T_(cmb) ~ 4 × 10^(-6) for P either Q or U and T_(cmb) ≃ 2.7 K) at 100, 143, 217 and 353 GHz. It will lead to major improvements in our understanding of the cosmic microwave background anisotropies and polarized foreground signals. Planck will make high resolution measurements of the E-mode spectrum (up to l ~ 1500) and will also play a prominent role in the search for the faint imprint of primordial gravitational waves on the CMB polarization. This paper addresses the effects of calibration of both temperature (gain) and polarization (polarization efficiency and detector orientation) on polarization measurements. The specific requirements on the polarization parameters of the instrument are set and we report on their pre-flight measurement on HFI bolometers. We present a semi-analytical method that exactly accounts for the scanning strategy of the instrument as well as the combination of different detectors. We use this method to propagate errors through to the CMB angular power spectra in the particular case of Planck-HFI, and to derive constraints on polarization parameters. We show that in order to limit the systematic error to 10% of the cosmic variance of the E-mode power spectrum, uncertainties in gain, polarization efficiency and detector orientation must be below 0.15%, 0.3% and 1° respectively. Pre-launch ground measurements reported in this paper already fulfill these requirements

    The research buyer\u27s perspective of market research effectiveness

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    This study examines the views of research buyers about the efficacy of market research used within their firms. A sample of research buyers from Australia's top 1000 companies was asked to evaluate the research outcomes of their most recent market research project in terms of their overall business strategy. Specialist market research buyers (insights managers) believed their commissioned research was very effective. This was in contrast to research buyers in generalist roles who did not believe in the effectiveness of the research outcomes to the same extent. The overarchlng strategic direction adopted by the buyer's firm did not make a difference to the type of research conducted (,action orientated' vs. 'knowledge enhancing'). However, entrepreneurial firms were more likely to rate their research as effective and to have dedicated research buyers generating insights into their markets. The results of this study are inconsistent with earlier studies and indicate that the market research function within Australian firms stili plays an ambiguous role

    Current developments of nanoscale insight into corrosion protection by passive oxide films

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    Oxide passive films are a key for the durability of metals and alloys components as well as a central issue in corrosion science and engineering. Herein, we discuss current developments of the nanometer and sub-nanometer scale knowledge of the barrier properties and adsorption properties of passive oxide films brought by recent model experimental and theoretical investigations. The discussed aspects include (i) the chromium enrichment and its homogeneity at the nanoscale in passive films formed on Cr-bearing alloys such as stainless steel, (ii) the corrosion properties of grain boundaries in early intergranular corrosion before penetration and propagation in the grain boundary network, and (iii) the interaction of organic inhibitor molecules with incompletely passivated metallic surfaces. In all three cases, key issues are highlighted and future developments that we consider as most relevant are identified.Comment: Current Opinion in Solid State and Materials Science, Elsevier, final accepted preprin

    Investigation of Attitudes Towards Security Behaviors

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    Cybersecurity attacks have increased as Internet technology has proliferated. Symantec’s 2013 Internet Security Report stated that two out of the top three causes of data breaches in 2012 were attributable to human error (Pelgrin, 2014). This suggests a need to educate end users so that they engage in behaviors that increase their cybersecurity. This study researched how a user’s knowledge affects their engagement in security behaviors. Security behaviors were operationalized into two categories: cyber hygiene and threat response behaviors. A sample of 194 San José State University students were recruited to participate in an observational study. Students completed a card sort, a semantic knowledge quiz, and a survey of their intention to perform security behaviors. A personality inventory was included to see if there would be any effects of personality on security behaviors. Multiple regression was used to see how card sorting and semantic knowledge quiz scores predicted security behaviors, but the results were not significant. Despite this, there was a correlation between cyber hygiene behaviors and threat response behaviors, as well as the Big Five personality traits. The results showed that many of the Big Five personality traits correlated with each other, which is consistent with other studies’ findings. The only personality trait that had a correlation with one of the knowledge measures was neuroticism, in which neuroticism had a negative correlation with the semantic knowledge quiz. Implications for future research are discussed to understand how knowledge, cyber hygiene behaviors, and threat response behaviors relate
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