10,265 research outputs found

    Quasinormal Modes of Self-Dual Warped AdS3_3 Black Hole in Topological Massive Gravity

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    We consider the various perturbations of self-dual warped AdS3_3 black hole and obtain the exact expressions of quasinormal modes by imposing the vanishing Dirichlet boundary condition at asymptotic infinity. It is expected that the quasinormal modes agree with the poles of retarded Green's functions of the dual CFT. Our results provide a quantitative test of the warped AdS/CFT correspondence.Comment: 10 pages, no figure, some references and comments on gravitational perturbations are adde

    Siamese Instance Search for Tracking

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    In this paper we present a tracker, which is radically different from state-of-the-art trackers: we apply no model updating, no occlusion detection, no combination of trackers, no geometric matching, and still deliver state-of-the-art tracking performance, as demonstrated on the popular online tracking benchmark (OTB) and six very challenging YouTube videos. The presented tracker simply matches the initial patch of the target in the first frame with candidates in a new frame and returns the most similar patch by a learned matching function. The strength of the matching function comes from being extensively trained generically, i.e., without any data of the target, using a Siamese deep neural network, which we design for tracking. Once learned, the matching function is used as is, without any adapting, to track previously unseen targets. It turns out that the learned matching function is so powerful that a simple tracker built upon it, coined Siamese INstance search Tracker, SINT, which only uses the original observation of the target from the first frame, suffices to reach state-of-the-art performance. Further, we show the proposed tracker even allows for target re-identification after the target was absent for a complete video shot.Comment: This paper is accepted to the IEEE Conference on Computer Vision and Pattern Recognition, 201

    Bootstrapping O(N)O(N) Vector Models in 4<d<64<d<6

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    We use the conformal bootstrap to study conformal field theories with O(N)O(N) global symmetry in d=5d=5 and d=5.95d=5.95 spacetime dimensions that have a scalar operator ϕi\phi_i transforming as an O(N)O(N) vector. The crossing symmetry of the four-point function of this O(N)O(N) vector operator, along with unitarity assumptions, determine constraints on the scaling dimensions of conformal primary operators in the ϕi×ϕj\phi_i \times \phi_j OPE. Imposing a lower bound on the second smallest scaling dimension of such an O(N)O(N)-singlet conformal primary, and varying the scaling dimension of the lowest one, we obtain an allowed region that exhibits a kink located very close to the interacting O(N)O(N)-symmetric CFT conjectured to exist recently by Fei, Giombi, and Klebanov. Under reasonable assumptions on the dimension of the second lowest O(N)O(N) singlet in the ϕi×ϕj\phi_i \times \phi_j OPE, we observe that this kink disappears in d=5d =5 for small enough NN, suggesting that in this case an interacting O(N)O(N) CFT may cease to exist for NN below a certain critical value.Comment: 24 pages, 5 figures; v2 minor improvement

    Measuring the energy handling capability of metal oxide varistors

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    Metal oxide varistors are widely used in many power electronics circuits to protect against transient over voltages. Certain applications are very demanding on the energy handling capability of the varistors. This paper gives an overview of the failure modes of ZnO varistors and investigates their characteristics when subjected to repetitive current pulses. It describes the puncture failure mode caused by melting of a region in the varistor of local current concentration. Experimental tests are performed to evaluate the puncture energy using an infrared imaging camera. A relationship between the energy absorption and the varistor maximum surface temperature is obtained. It is shown that the destructive energy depends strongly on the uniformity of the varistor; the more uniform, the higher the energy handling capability. The paper also presents the results of nondestructive tests using a scanning acoustic microscope to evaluate the uniformity of the varistor

    Health Policy for Improving Population Mental Health in Contemporary Rural China

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    Topic Theme: T02 - The EnvironmentPanel: P03 - Public Health Policy: 'World Wellness' Framework For Preventing Illness and Improving Population Health: abstract no. T02P03-03The Conference is co-sponsored by the Faculty of Social Sciences of the University of Hong Kong, Sol Price School of Public Policy of University of Southern California and International Public Policy Associationpublished_or_final_versio
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