1,036 research outputs found

    The slicing dependence of non-spherically symmetric quasi-local horizons in Vaidya Spacetimes

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    It is well known that quasi-local black hole horizons depend on the choice of a time coordinate in a spacetime. This has implications for notions such as the surface of the black hole and also on quasi-local physical quantities such as horizon measures of mass and angular momentum. In this paper, we compare different horizons on non-spherically symmetric slicings of Vaidya spacetimes. The spacetimes we investigate include both accreting and evaporating black holes. For some simple choices of the Vaidya mass function function corresponding to collapse of a hollow shell, we compare the area for the numerically found axisymmetric trapping horizons with the area of the spherically symmetric trapping horizon and event horizon. We find that as expected, both the location and area are dependent on the choice of foliation. However, the area variation is not large, of order 0.035%0.035\% for a slowly evolving horizon with m˙=0.02\dot{m}=0.02. We also calculate analytically the difference in area between the spherically symmetric quasi-local horizon and event horizon for a slowly accreting black hole. We find that the difference can be many orders of magnitude larger than the Planck area for sufficiently large black holes.Comment: 10 pages, 5 figures, corrected minor typo

    Does Internet Harms Music Sales? a Constructive Perspective

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    The main issue brought by this study is whether internet as medium and their users as actors behind the fall of music industry\u27s revenue during these years – many people stand on this point of view - or could be the facilitator of music purchasing. This study used data panel from 16 countries ranging from 1999 to 2004 to prove whether internet and their users harm the revenue of music industry, and employs four dummy variables, including piracy rates, economic development, market size, and individualism/collectivism. The results indicated that internet through their users in the USA does not harm as much as industry claimed before, only 2.1 percent. Furthermore, the panel data results indicate that level of piracy rates released by IFPI in 2001 partially supported, and surprisingly, the internet positively significant influences on the music sales for country\u27s with piracy level in the range of 25 to 50 percent. Moreover, the internet users interact with economic development and individualism/collectivism, and it has shown that internet users have positively significant impacts on the music sales. However, market size does not support the model developed in this study. The managerial implications, limitations of the study and directions for further research are also presented. Keywords: internet, piracy, music sales, piracy rates, economic development, market size, individualism/collectivism

    Effective Viscous Damping Enables Morphological Computation in Legged Locomotion

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    Muscle models and animal observations suggest that physical damping is beneficial for stabilization. Still, only a few implementations of mechanical damping exist in compliant robotic legged locomotion. It remains unclear how physical damping can be exploited for locomotion tasks, while its advantages as sensor-free, adaptive force- and negative work-producing actuators are promising. In a simplified numerical leg model, we studied the energy dissipation from viscous and Coulomb damping during vertical drops with ground-level perturbations. A parallel spring-damper is engaged between touch-down and mid-stance, and its damper auto-disengages during mid-stance and takeoff. Our simulations indicate that an adjustable and viscous damper is desired. In hardware we explored effective viscous damping and adjustability and quantified the dissipated energy. We tested two mechanical, leg-mounted damping mechanisms; a commercial hydraulic damper, and a custom-made pneumatic damper. The pneumatic damper exploits a rolling diaphragm with an adjustable orifice, minimizing Coulomb damping effects while permitting adjustable resistance. Experimental results show that the leg-mounted, hydraulic damper exhibits the most effective viscous damping. Adjusting the orifice setting did not result in substantial changes of dissipated energy per drop, unlike adjusting damping parameters in the numerical model. Consequently, we also emphasize the importance of characterizing physical dampers during real legged impacts to evaluate their effectiveness for compliant legged locomotion

    Reducing the number of templates for aligned-spin compact binary coalescence gravitational wave searches using metric-agnostic template nudging

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    Efficient multi-dimensional template placement is crucial in computationally intensive matched-filtering searches for Gravitational Waves (GWs). Here, we implement the Neighboring Cell Algorithm (NCA) to improve the detection volume of an existing Compact Binary Coalescence (CBC) template bank. This algorithm has already been successfully applied for a binary millisecond pulsar search in data from the Fermi satellite. It repositions templates from over-dense regions to under-dense regions and reduces the number of templates that would have been required by a stochastic method to achieve the same detection volume. Our method is readily generalizable to other CBC parameter spaces. Here we apply this method to the aligned--single-spin neutron-star--black-hole binary coalescence inspiral-merger-ringdown gravitational wave parameter space. We show that the template nudging algorithm can attain the equivalent effectualness of the stochastic method with 12% fewer templates

    Diplomasi Palestina Menjadi Negara Pengamat Non- Anggota Di Perserikatan Bangsa-bangsa (Pbb) Tahun 2011-2012

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    This research aimed to describe how Palestine movement to get independence and recognition from all above United Nations member state. In this research will explain the progess of Palestine‟s Authority to become non-member observer state in United Nations. Authority of Palestine was the Palestine‟s people representation that had right to vote and right to submit point of view at International forum. Palestine Liberazation Organization (PLO) take important role for Palestine movement. In any relations, especially foreign relations, Palestine had some of good attitude. But all of Palestine disputes with Israel hamper the independence of Palestine.Researcher analyzed this case using qualitative methods to find data and facts through some literature. The literature collected from books, journals, mass media and websites. Researcher use realism perspective. The level analysis of the research is nation-state and also use International cooperation theory by K.J. Holsti.From this research it can be seen, Palestine used some steps toward International rezime. There are three steps that will shown in this research. First, by using confference diplomacy, under Mahmoud Abbas rezime as President of Palestine‟s Authority used diplomatic relations with other nation state with delivery speech in front of the forum. Second steps with parlementary diplomacy made Palestine as a non-member observer state in United Nations after 67th general assembly at 44th panel discussion on November 29th, 2012. This result supported by 138 countries, rejected by 9 countries, 41 counstries abstain, and 5 countries absen. The last step from Palestine movement for recognition by using International organization. This seen when Palestine joined as a full membership of UNESCO. Also use of „state of Palestine” in any diplomatic relations and International organization

    The burden and risk factors for adverse drug events in older patients - a prospective cross-sectional study

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    Objective: To determine the burden and risk factors for adverse drug events (ADEs) in older patients. Design: A prospective cross-sectional study. Methods: Patients (65 years and older) presenting to the tertiary Emergency Unit of Groote Schuur Hospital, Cape Town, between February and May 2005, were assessed for well established ADEs, as defined by the South African Medicines Formulary. Logistic regression models were fitted to determine drugs and other factors associated with the likelihood of developing ADEs. Results: ADEs were identified in 104 of the 517 (20%) presentations. The most frequently involved drug classes were cardiovascular (34%), anticoagulant (27%), analgesic (19%) and antidiabetic (9%). Patients who developed ADEs were more likely to have five or more prescription drugs (p < 0.0001), more than three clinical problems (p = 0.001), require admission (p = 0.04), and report compliance with medication (p = 0.02) than those who did not. Drugs shown to independently confer increased risk of ADEs were angiotensin-converting enzyme inhibitors (RR = 2.6, 95% CI: 1.3 - 5.2, p = 0.009), non-steroidal anti-inflammatory drugs (RR = 4.1, 95% CI: 2.1 - 8.0, p < 0.0001) and warfarin (RR = 3.1, 95% CI: 1.6 - 6.3, p = 0.0014). Conclusion: ADEs contribute significantly to the burden of elderly care in the Emergency Unit. In a setting such as ours, increased pill burden and certain drug classes are likely to result in increased risk of ADEs in the older population group.South African Medical Journal Vol. 96 (12) 2006: pp. 1255-125

    Rancang Bangun Sistem Regulations Legislation Library Di Sekretariat Dprd Kabupaten Jombang Menggunakan Embarcadero Delphi Xe3

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    Parliament Secretariat is agency that provides administrative services and providers to support the smooth running of secretarial duties and legislative functions as place where had made rules and regulations that apply in that area .Information technology facilities utilization is required to increase effectiveness and efficiency the performance of secretariat really can be better so the application of technology in the scope of government and the duties more optimal.A large number of books and legal regulations legislation can be managed as benefits the library at Parliament Secretariat. the classification system is required so that the circulation of information,archive and document storage becomes more accurate and well-organized.So that the authors design a system information books and regulations legislation data in the scope of the Parliament secretariat institutions.In this study realized "Design System of 'Regulations Legislation Library'at the Jombang Parliament Secretariat Using Embarcadero Delphi XE3" with Touch technology and MYSQL as database server

    Sistem Organisasi Kognitif Dan Afektif Dan Pengaruhnya Terhadap Kinerja Apotek Di Surabaya: Efek Moderasi Orientasi Kewirausahaan

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    : Apothecary is a highly regulated and competitive industry due to less differentiation and high density in certain areas. Interestingly, the performance of apothecaries is heterogeneous; and based on market orientation perspective we argue that the condition exists due to different level on responding competitors\u27 actions as well as customers\u27 needs. Further, we argue that managers\u27 entrepreneurial orientation can strengthen these relationships. The mechanism of how can apothecaries develop their responsiveness to competitors and customers also is investigated. We distributed questionnaires among apopthecary managers in Surabaya and generated 131 responses. By using PLS, the results indicate that responsiveness to competitors positively influence on their performance, while responsiveness to customers is not. The moderating effect of entrepreneurial orientation is also not confirmed. Responsiveness to competitors is highly determined by cognitive and affective organizational system, while responsiveness to customers mainly determined by affective organizational system. Managerial and academic implications are further discussed in this paper

    Pengaruh Nilai Informasi Dan Sosial Pada Co-Consumption Dan Co-Production Antar Anggota Kaskus: Perspektif Modal Sosial

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    Consumers co-create values through co-consumption (with other consumers) and co-production (with producers). This study argues that members\u27 perceptions on informational and social values contribute to co-creation, which is stronger when they have greater product involvement. Further arguments indicate that members\u27 perceptions on informational and social values are determined by social capital inside the community. The developed hypotheses are tested on 204 Kaskus community members who are affiliated with 6 different brands on two product categories, mobile phone and snack. The results indicate that social capital positively influences members\u27 perception on informational and social values. Social value influence co-consumption and co-production, while informational value mainly influence co-production. The moderating effect of product involvement exists on the influence of social value on co-production
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