716 research outputs found

    Economic and monetary union in Europe

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    The plans for Economic and Monetary Union in Europe became difficult to achieve during the period 1992-1993. The convergence criteria set up in the Maastricht Treaty block the road towards unification. It is very complex to expect twelve governments with different shades of political colour and twelve states with different economic interests to compromise in such criteria (as inflation, government borrowing, exchange rate stability and interest rates) and eventually, speak with one voice at the end of this decade. This current research provides significant modifications in The Maastricht Treaty , policy making, objectives, even changes in political behavior for better coordination to tackle any turbulence that stands on the way. These changes were unveiled and supported by outside views. The right time for transition to the monetary union depends on the rate of progress in Europe in meeting the stability requirements and in the willingness to move to a more developed political union. Monetary Union could occur late in 1990s but with a number of members left out with major dominant the Germany than the EMS

    Compression-compression fatigue of Pd_(43)Ni_(10)Cu_(27)P_(20) metallic glass foam

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    Compression-compression fatigue testing of metallic-glass foam is performed. A stress-life curve is constructed, which reveals an endurance limit at a fatigue ratio of about 0.1. The origin of fatigue resistance of this foam is identified to be the tendency of intracellular struts to undergo elastic and reversible buckling, while the fatigue process is understood to advance by anelastic strut buckling leading to localized plasticity (shear banding) and ultimate strut fracture. Curves of peak and valley strain versus number of cycles coupled with plots of hysteresis loops and estimates of energy dissipation at various loading cycles confirm the four stages of foam-fatigue

    Who Watches the Watchers: A Multi-Task Benchmark for Anomaly Detection

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    A driver in the rise of IoT systems has been the relative ease with which it is possible to create specialized-but- adaptable deployments from cost-effective components. Such components tend to be relatively unreliable and resource poor, but are increasingly widely connected. As a result, IoT systems are subject both to component failures and to the attacks that are an inevitable consequence of wide-area connectivity. Anomaly detection systems are therefore a cornerstone of effective operation; however, in the literature, there is no established common basis for the evaluation of anomaly detection systems for these environments. No common set of benchmarks or metrics exists and authors typically provide results for just one scenario. This is profoundly unhelpful to designers of IoT systems, who need to make a choice about anomaly detection that takes into account both ease of deployment and likely detection performance in their context. To address this problem, we introduce Aftershoc k, a multi-task benchmark. We adapt and standardize an array of datasets from the public literature into anomaly detection-specific benchmarks. We then proceed to apply a diverse set of existing anomaly detection algorithms to our datasets, producing a set of performance baselines for future comparisons. Results are reported via a dedicated online platform located at https://aftershock. dev, allowing system designers to evaluate the general applicability and practical utility of various anomaly detection models. This approach of public evaluation against common criteria is inspired by the immensely useful community resources found in areas such as natural language processing, recommender systems, and reinforcement learning. We collect, adapt, and make available 10 anomaly detection tasks which we use to evaluate 6 state-of-the-art solutions as well as common baselines. We offer researchers a submission system to evaluate future solutions in a transparent manner and we are actively engaging with academic and industry partners to expand the set of available tasks. Moreover, we are exploring options to add hardware-in-the-loop. As a community contribution, we invite researchers to train their own models (or those reported by others) on the public development datasets available on the online platform, submitting them for independent evaluation and reporting results against others

    Oxidation Behavior of a Pd_(43)Cu_(27)Ni_(10)P_(20) Bulk Metallic Glass and Foam in Dry Air

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    The oxidation behavior of both Pd_(43)Cu_(27)Ni_(10)P_(20) bulk metallic glass (Pd4-BMG) and its amorphous foam containing 45 pct porosity (Pd4-AF) was investigated over the temperature range of 343 K (70 °C) to 623 K (350 °C) in dry air. The results showed that virtually no oxidation occurred in the Pd4-BMG at T < 523 K (250 °C), revealing the alloy’s favorable oxidation resistance in this temperature range. In addition, the oxidation kinetics at T ≥ 523 K (250 °C) followed a parabolic-rate law, and the parabolic-rate constants (k_p values) generally increased with temperature. It was found that the oxidation k_p values of the Pd4-AF are slightly lower than those of the Pd4-BMG, indicating that the porous structure contributes to improving the overall oxidation resistance. The scale formed on the alloys was composed exclusively of CuO at T ≥ 548 K (275 °C), whose thickness gradually increased with increasing temperature. In addition, the amorphous structure remained unchanged at T ≤ 548 K (275 °C), while a triplex-phase structure developed after the oxidation at higher temperatures, consisting of Pd_2Ni_2P, Cu_3P, and Pd_3P

    Resolving the predicament of android custom permissions

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    Android leverages a set of system permissions to protect platform resources. At the same time, it allows untrusted third-party applications to declare their own custom permissions to regulate access to app components. However, Android treats custom permissions the same way as system permissions even though they are declared by entities of different trust levels. In this work, we describe two new classes of vulnerabilities that arise from the ‘predicament’ created by mixing system and custom permissions in Android. These have been acknowledged as serious security flaws by Google and we demonstrate how they can be exploited in practice to gain unauthorized access to platform resources and to compromise popular Android apps. To address the shortcomings of the system, we propose a new modular design called Cusper for the Android permission model. Cusper separates the management of system and custom permissions and introduces a backward-compatible naming convention for custom permissions to prevent custom permission spoofing. We validate the correctness of Cusper by 1) introducing the first formal model of Android runtime permissions, 2) extending it to describe Cusper, and 3) formally showing that key security properties that can be violated in the current permission model are always satisfied in Cusper. To demonstrate Cusper’s practicality, we implemented it in the Android platform and showed that it is both effective and efficient

    Dynamical and quasistatic structural relaxation paths in Pd_(40)Ni_(40)P_(20) glass

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    By sequential heat treatment of a Pd_(40)Ni_(40)P_(20) metallic glass at temperatures and durations for which α-relaxation is not possible, dynamic, and quasistatic relaxation paths below the glass transition are identified via ex situ ultrasonic measurements following each heat treatment. The dynamic relaxation paths are associated with hopping between nonequilibrium potential energy states of the glass, while the quasistatic relaxation path is associated with reversible β-relaxation events toward quasiequilibrium states. These quasiequilibrium states are identified with secondary potential energy minima that exist within the inherent energy minimum of the glass, thereby supporting the concept of the sub-basin/metabasin organization of the potential-energy landscape

    Parental and peer support and modelling in relation to domain-specific physical activity participation in boys and girls from Germany

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    Background Physical activity (PA) as a precondition of child development is related with social environmental correlates. However, domain-specific PA and gender issues have been neglected in studies on social support and modelling and PA in school-aged children. The aim of this study was to assess the relationships of parental and peer modelling and social support with domain-specific PA participation in a large sample of school-aged children, taking gender into account. Methods 3,505 school children aged 6 to 17 years old participated in the German nationwide ‘MoMo’ cohort-study. By using the MoMo-PAQ the participants and their parents provided self-report data on perceived social support and social modelling and domain-specific PA participation. Relationships of social environmental variables and the physical outcomes were analysed by logistic regression analyses. Results At secondary school level, girls were less likely than boys to participate in physical activity in and outside of sports clubs, extra-curricular physical activity and in outdoor play (p < 0.05), but at primary school level this pattern only applied to club sport (p < 0.01). Girls also received less social support than boys (p < 0.01). Physical activity participation in all domains was associated with any of the social support and modelling variables and differences between physical activity domains and between boys and girls occurred. Most consistently physical activity in sports clubs was related with the social environmental correlates in boys (primary school: R2 = 0.60; secondary school: R2 = 0.45) and girls (primary school: R2 = 0.53; secondary school: R2 = 0.47). Conclusions In future, reciprocal relationships of social environmental variables and PA should be considered in longitudinal studies to obtain insights into the direction of the associations. Furthermore, interventions encompassing the social environment and focussed particularly on the promotion of domain-specific PA in girls in secondary school-age are warranted

    Parental and peer support and modelling in relation to domain-specific physical activity participation in boys and girls from Germany

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    Background Physical activity (PA) as a precondition of child development is related with social environmental correlates. However, domain-specific PA and gender issues have been neglected in studies on social support and modelling and PA in school-aged children. The aim of this study was to assess the relationships of parental and peer modelling and social support with domain-specific PA participation in a large sample of school-aged children, taking gender into account. Methods 3,505 school children aged 6 to 17 years old participated in the German nationwide ‘MoMo’ cohort-study. By using the MoMo-PAQ the participants and their parents provided self-report data on perceived social support and social modelling and domain-specific PA participation. Relationships of social environmental variables and the physical outcomes were analysed by logistic regression analyses. Results At secondary school level, girls were less likely than boys to participate in physical activity in and outside of sports clubs, extra-curricular physical activity and in outdoor play (p < 0.05), but at primary school level this pattern only applied to club sport (p < 0.01). Girls also received less social support than boys (p < 0.01). Physical activity participation in all domains was associated with any of the social support and modelling variables and differences between physical activity domains and between boys and girls occurred. Most consistently physical activity in sports clubs was related with the social environmental correlates in boys (primary school: R2 = 0.60; secondary school: R2 = 0.45) and girls (primary school: R2 = 0.53; secondary school: R2 = 0.47). Conclusions In future, reciprocal relationships of social environmental variables and PA should be considered in longitudinal studies to obtain insights into the direction of the associations. Furthermore, interventions encompassing the social environment and focussed particularly on the promotion of domain-specific PA in girls in secondary school-age are warranted

    Direct observation of an irradiance dependent nonlinear refraction in CVD single layer graphene

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    The nonlinear optical properties of single layer graphene are studied via Z-scan. The measurements are carried out at 1045 nm with a 360 femtosecond highly stable Yb doped mode-locked fiber laser. Under laser illumination single-layer graphene exhibits both a transmittance increase due to saturable absorption and a nonlinear phase-shift due to nonlinear refraction. The nonlinear refraction measurements were carried out from 0.5 to 8 GW/cm(2) revealing an expected irradiance-dependent nonlinear refraction. An effective nonlinear refractive index coefficient (n) over tilde (I) is used to describe this and discriminate it from the conventional n(2) coefficient usually measured by Z-scan. The saturation level of the nonlinear phase-shift where the nonlinear response becomes irradiance dependent is deduced from the experimental data
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