4,869 research outputs found

    Website Satisfaction Dan Commercial Friendships Sebagai Strategi Pemasaran Untuk Mencapai Keuntungan Jangka Panjang

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    With the realization of globalization in the world economies, market opportunities seem to be never-ending. Companies must be fast and always advance in achieving better performance and in delivering the optimal satisfaction for its customers. Internet has opened a superhighway of higher level of competition which information is vulnerable. Because of this by integrating the Internet technology into marketing strategy, companies will be able to enjoy the fullest competitive advantages offered by the internet. This article promotes web satisfaction and friendships as a means for company in achieving long term profitability.  Consumers who are satisfied with the company’s website generate loyalty as seen the level of repurchase behavior, intention to buy and positive word of mouth.  Meanwhile the degree of friendship also influences satisfaction between the interaction of provider and its customer

    Submillimeter H2O masers in water-fountain nebulae

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    We report the first detection of submillimeter water maser emission toward water-fountain nebulae, which are post-AGB stars that exhibit high-velocity water masers. Using APEX we found emission in the ortho-H2O (10_29-9_36) transition at 321.226 GHz toward three sources: IRAS 15445-5449, IRAS 18043-2116 and IRAS 18286-0959. Similarly to the 22 GHz masers, the submillimeter water masers are expanding with a velocity larger than that of the OH masers, suggesting that these masers also originate in fast bipolar outflows. In IRAS 18043-2116 and IRAS 18286-0959, which figure among the sources with the fastest water masers, the velocity range of the 321 GHz masers coincides with that of the 22 GHz masers, indicating that they likely coexist. Towards IRAS 15445-5449 the submillimeter masers appear in a different velocity range, indicating that they are tracing different regions. The intensity of the submillimeter masers is comparable to that of the 22 GHz masers, implying that the kinetic temperature of the region where the masers originate should be Tk > 1000 K. We propose that the passage of two shocks through the same gas can create the conditions necessary to explain the presence of strong high-velocity 321 GHz masers coexisting with the 22 GHz masers in the same region.Comment: 4 pages, 1 figure. Accepted for publication in A&A Letter

    Monotonic Prefix Consistency in Distributed Systems

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    We study the issue of data consistency in distributed systems. Specifically, we consider a distributed system that replicates its data at multiple sites, which is prone to partitions, and which is assumed to be available (in the sense that queries are always eventually answered). In such a setting, strong consistency, where all replicas of the system apply synchronously every operation, is not possible to implement. However, many weaker consistency criteria that allow a greater number of behaviors than strong consistency, are implementable in available distributed systems. We focus on determining the strongest consistency criterion that can be implemented in a convergent and available distributed system that tolerates partitions. We focus on objects where the set of operations can be split into updates and queries. We show that no criterion stronger than Monotonic Prefix Consistency (MPC) can be implemented.Comment: Submitted pape

    First principles derivation of a Rayleigh Gans Debye model for scattering from anisotropic inhomogeneities

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    Scattering problems are important in describing light propagation in wide ranging media such as the atmosphere, colloidal solutions, metamaterials, glass ceramic composites, transparent polycrystalline ceramics, and surfaces. The Rayleigh Gans Debye (RGD) approximation has enjoyed great success in describing a wide range of scattering phenomena. We derive a generalized RGD formulation from the perturbation of Maxwell equations. In contrast to most treatments of RGD scattering, our formulation can model any soft scattering phenomena in linear media, including scattering by stochastic process, lossy media, and by anisotropic inhomogeneities occurring at multiple length scales. Our first-principles derivation makes explicit underlying assumptions and provides jumping off points for more general treatments. The derivation also facilitates a deeper understanding of soft scattering. It is demonstrated that sources of scattering are not interfaces as is often presumed, but excess accelerating charges emitting uncompensated radiation. Approximations to the equations are also presented and discussed. For example, the scattering coefficient in the large size RGD limit is shown to be proportional to the correlation length and the variance of a projected phase shift

    Quantum evolution according to real clocks

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    We characterize good clocks, which are naturally subject to fluctuations, in statistical terms. We also obtain the master equation that governs the evolution of quantum systems according to these clocks and find its general solution. This master equation is diffusive and produces loss of coherence. Moreover, real clocks can be described in terms of effective interactions that are nonlocal in time. Alternatively, they can be modeled by an effective thermal bath coupled to the system.Comment: RevTeX 3.01, 6 page

    An Origin of the Huge Far-Infrared Luminosity of Starburst Mergers

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    Recently Taniguchi and Ohyama found that the higher 12^{12}CO to 13^{13}CO integrated intensity ratios at a transition JJ=1--0, R=I(12R = I(^{12}CO)/I(13/I(^{13}CO) 20\gtrsim 20, in a sample of starburst merging galaxies such as Arp 220 are mainly attributed to the depression of 13^{13}CO emission with respect to 12^{12}CO. Investigating the same sample of galaxies analyzed by Taniguchi & Ohyama, we find that there is a tight, almost linear correlation between the dust mass and 13^{13}CO luminosity. This implies that dust grains are also depressed in the high-RR starburst mergers, leading to the higher dust temperature (TdT_{\rm d}) in them because of the relative increase in the radiation density. Nevertheless, the average dust mass (MdM_{\rm d}) of the high-RR starburst mergers is higher significantly than that of non-high RR galaxies. This is naturally understood because the galaxy mergers could accumulate a lot of dust grains from their progenitor galaxies together with supply of dust grains formed newly in the star forming regions. Since LL(FIR) MdTd5\propto M_{\rm d} T_{\rm d}^5 given the dust emissivity law, Sνλ1S_\nu \propto \lambda^{-1}, the increases in both MdM_{\rm d} and TdT_{\rm d} explain well why the starburst mergers are so bright in the FIR. We discuss that the superwind activity plays an important role in destroying dust grains as well as dense gas clouds in the central region of mergers.Comment: 10 pages (aaspp4.sty), 3 postscript figures (embedded). Accepted for publication in Astrophysical Journal Letter

    Large Solar Neutrino Mixing in an Extended Zee Model

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    The Zee model, which employs the standard Higgs scalar (ϕ\phi) with its duplicate (ϕ\phi^\prime) and a singly charged scalar (h+h^+), can utilize two global symmetries associated with the conservation of the numbers of ϕ\phi and ϕ\phi^\prime, Nϕ,ϕN_{\phi,\phi^\prime}, where Nϕ+NϕN_\phi+N_{\phi^\prime} coincides with the hypercharge while NϕNϕN_\phi-N_{\phi^\prime} (X\equiv X) is a new conserved charge, which is identical to LeLμLτL_e-L_\mu-L_\tau for the left-handed leptons. Charged leptons turn out to have ee-μ\mu and ee-τ\tau mixing masses, which are found to be crucial for the large solar neutrino mixing. In an extended version of the Zee model with an extra triplet Higgs scalar (s), neutrino oscillations are described by three steps: 1) the maximal atmospheric mixing is induced by democratic mass terms supplied by ss with XX=2 that can initiate the type II seesaw mechanism for the smallness of these masses; 2) the maximal solar neutrino mixing is triggered by the creation of radiative masses by h+h^+ with XX = 0; 3) the large solar neutrino mixing is finally induced by a νμ\nu_\mu-ντ\nu_\tau mixing arising from the rotation of the radiative mass terms as a result of the diagonalization that converts ee-μ\mu and ee-τ\tau mixing masses into the electron mass.Comment: RevTex, 10 pages including one figure page, to be published in Int. J. Mod. Phys. A (2002

    Quantum Electromagnetic Wormholes and Geometrical Description of the Electric Charge

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    I present and discuss a class of solutions of the Wheeler-de Witt equation describing wormholes generated by coupling of gravity to the electromagnetic field for Kantowski-Sachs and Bianchi I spacetimes. Since the electric charge can be viewed as electric lines of force trapped in a finite region of spacetime, these solutions can be interpreted as the quantum corresponding of the Ein\-stein\--Ro\-sen\--Mis\-ner\--Whee\-ler electromagnetic geon.Comment: 13 pages, PLAIN TEX, Report No: SISSA 92/94/A (to appear in Phys. Rev. D15

    Hilbert space of wormholes

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    Wormhole boundary conditions for the Wheeler--DeWitt equation can be derived from the path integral formulation. It is proposed that the wormhole wave function must be square integrable in the maximal analytic extension of minisuperspace. Quantum wormholes can be invested with a Hilbert space structure, the inner product being naturally induced by the minisuperspace metric, in which the Wheeler--DeWitt operator is essentially self--adjoint. This provides us with a kind of probabilistic interpretation. In particular, giant wormholes will give extremely small contributions to any wormhole state. We also study the whole spectrum of the Wheeler--DeWitt operator and its role in the calculation of Green's functions and effective low energy interactions.Comment: 23 pages, 2 figures available upon request, REVTE

    Minimum Length from Quantum Mechanics and Classical General Relativity

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    We derive fundamental limits on measurements of position, arising from quantum mechanics and classical general relativity. First, we show that any primitive probe or target used in an experiment must be larger than the Planck length, lPl_P. This suggests a Planck-size {\it minimum ball} of uncertainty in any measurement. Next, we study interferometers (such as LIGO) whose precision is much finer than the size of any individual components and hence are not obviously limited by the minimum ball. Nevertheless, we deduce a fundamental limit on their accuracy of order lPl_P. Our results imply a {\it device independent} limit on possible position measurements.Comment: 8 pages, latex, to appear in the Physical Review Letter
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