4,388 research outputs found

    Mass and Angular momentum of Black Holes in New Massive Gravity

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    We obtain mass and angular momentum of black holes as conserved charges in three dimensional new massive gravity, after presenting the explicit expression for the potential of the conserved charges. This confirms the expression of those charges obtained in several ways, in particular through AdS/CFT correspondence, and shows us that the first law of black hole thermodynamics is valid in these black holes. We also comment about conserved charges in new type black holes with the emphasis on the AdS/CFT correspondence as guiding principle.Comment: minor corrections, added conclusion, accepted in PR

    Property Versus Misappropriation: Legal Protection for Databases in Korea

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    As a member of the international society which is now more interconnected than ever, Korea is experiencing a legal gap in the protection of databases. The commercial value of databases increased dramatically with the expanding use of computers and the Internet. As with other countries, Korea faces a choice in the legal forms of protection for databases: it can either extend the application of existing laws (i.e., patent and copyright protection) or create a new law (i.e., sui-generis database protection). In addition, Korea must choose either a property approach or a misappropriation approach for database protection. Although Korea attempted both approaches, there is still a controversy regarding which alternative will best guide Korea to prosperity in the digital age. This Essay argues that legislative proposals based on a property approach fail to cover the legal gap. A property approach has the potential to over-protect databases in Korea and negatively impact small innovators and the general public. Instead, this Essay submits that the misappropriation approach is the best alternative for the protection of databases in Korea. Unlike other countries such as the United States, Korea has not developed a misappropriation doctrine through case law or statutory provision. This lack of established law on the misappropriation doctrine points to a need for the enactment of a statutory provision explicitly prohibiting the misappropriation of databases in Korea

    The Guidelines of Material Design and Process Control on Hybrid Fiber Metal Laminate for Aircraft Structures

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    Fiber metal laminate (FML) is a hybrid material system that consists of thin metal sheets bonded into a laminate with intermediate thin fiber reinforced composite layers. The aerospace industry has recently increased their use of FMLs due to the considerable weight reduction and consequent benefits for critical load-carrying locations in commercial aircraft, such as upper fuselage skin panels. All FML materials and their processes should be qualified through enough tests and fabrication trials to demonstrate reproducible and reliable design criteria. In particular, proper surface treatment technologies are prerequisite for achieving long-term service capability through the adhesive bonding process. This chapter introduces a brief overview of design concept, material properties and process control methodologies to provide detailed background information with engineering practices and to help ensure stringent quality controls and substantiation of structure integrity. The guidelines and information found in this chapter are meant to be a documentation of current knowledge and an application of sound engineering principles to the FML part development for aerospace usage

    The 750 GeV Diphoton Excess May Not Imply a 750 GeV Resonance

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    We discuss non-standard interpretations of the 750 GeV diphoton excess recently reported by the ATLAS and CMS Collaborations which do not involve a new, relatively broad, resonance with a mass near 750 GeV. Instead, we consider the sequential cascade decay of a much heavier, possibly quite narrow, resonance into two photons along with one or more invisible particles. The resulting diphoton invariant mass signal is generically rather broad, as suggested by the data. We examine three specific event topologies - the antler, the sandwich, and the 2-step cascade decay, and show that they all can provide a good fit to the observed published data. In each case, we delineate the preferred mass parameter space selected by the best fit. In spite of the presence of invisible particles in the final state, the measured missing transverse energy is moderate, due to its anti- correlation with the diphoton invariant mass. We comment on the future prospects of discriminating with higher statistics between our scenarios, as well as from more conventional interpretations.Comment: Discussion about the ATLAS Moriond EW2016 added. Matched to PRL accepted versio

    The Role of Evaluability Bias and the Fairness Effect in the Escalation of Commitment to Troubled Software Product Development Projects

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    New software product development entails considerable risks. One significant risk is that decision makers can become overly committed to troubled software product development projects (i.e., escalation of commitment). While prior research has identified factors that promote escalation in information technology projects, there has been little attempt to leverage the context of software product development, which can include evaluating attributes of a software product under development and weighing a personal financial reward tied to a successful product launch. In this study, we conducted two experiments to investigate how evaluability bias concerning software attributes and the fairness effect that arises from the relative amount of a personal financial reward influence the escalation of commitment to troubled software product development projects. Our findings suggest that the escalation of commitment to troubled software product development projects is influenced by both evaluability bias, which affects the perceived attractiveness of a software product under development, and the fairness effect, which influences the perceived attractiveness of a personal financial reward tied to a successful product launch. This study contributes to both the information systems literature and the escalation literature by providing novel theoretical explanations as to why escalation occurs in the context of new software product developmen

    Polarity engineering in polycrystalline ZnO by inversion boundaries

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    Two distinctive polarity-engineered microstructures were obtained in polycrystalline ZnO ceramics by inducing two different types of inversion boundaries (IBs) inside individual grains to examine the effect of the different polarities on the varistor performances. The presence of head-to-head IBs induced by the addition of Sb and tail-to-tail IBs by doping Ti was directly confirmed by the characteristic geometry of the chemical etch pits. It was proposed that a consequent polarity on the grain boundary planes, which are affected by the presence of head-to-head IBs is crucial in exhibiting the superior performance of ZnO varistors.open2
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