359 research outputs found

    Video Propagation Networks

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    We propose a technique that propagates information forward through video data. The method is conceptually simple and can be applied to tasks that require the propagation of structured information, such as semantic labels, based on video content. We propose a 'Video Propagation Network' that processes video frames in an adaptive manner. The model is applied online: it propagates information forward without the need to access future frames. In particular we combine two components, a temporal bilateral network for dense and video adaptive filtering, followed by a spatial network to refine features and increased flexibility. We present experiments on video object segmentation and semantic video segmentation and show increased performance comparing to the best previous task-specific methods, while having favorable runtime. Additionally we demonstrate our approach on an example regression task of color propagation in a grayscale video.Comment: Appearing in Computer Vision and Pattern Recognition, 2017 (CVPR'17

    Semantic Video CNNs through Representation Warping

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    In this work, we propose a technique to convert CNN models for semantic segmentation of static images into CNNs for video data. We describe a warping method that can be used to augment existing architectures with very little extra computational cost. This module is called NetWarp and we demonstrate its use for a range of network architectures. The main design principle is to use optical flow of adjacent frames for warping internal network representations across time. A key insight of this work is that fast optical flow methods can be combined with many different CNN architectures for improved performance and end-to-end training. Experiments validate that the proposed approach incurs only little extra computational cost, while improving performance, when video streams are available. We achieve new state-of-the-art results on the CamVid and Cityscapes benchmark datasets and show consistent improvements over different baseline networks. Our code and models will be available at http://segmentation.is.tue.mpg.deComment: ICCV 201

    On a modular property of N=2 superconformal theories in four dimensions

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    In this note we discuss several properties of the Schur index of N=2 superconformal theories in four dimensions. In particular, we study modular properties of this index under SL(2,Z) transformations of its parameters.Comment: 23 page, 2 figure

    Exceptional Indices

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    Recently a prescription to compute the superconformal index for all theories of class S was proposed. In this paper we discuss some of the physical information which can be extracted from this index. We derive a simple criterion for the given theory of class S to have a decoupled free component and for it to have enhanced flavor symmetry. Furthermore, we establish a criterion for the "good", the "bad", and the "ugly" trichotomy of the theories. After interpreting the prescription to compute the index with non-maximal flavor symmetry as a residue calculus we address the computation of the index of the bad theories. In particular we suggest explicit expressions for the superconformal index of higher rank theories with E_n flavor symmetry, i.e. for the Hilbert series of the multi-instanton moduli space of E_n.Comment: 33 pages, 11 figures, v2: minor correction

    Localization of N=4 Superconformal Field Theory on S^1 x S^3 and Index

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    We provide the geometrical meaning of the N=4{\cal N}=4 superconformal index. With this interpretation, the N=4{\cal N}=4 superconformal index can be realized as the partition function on a Scherk-Schwarz deformed background. We apply the localization method in TQFT to compute the deformed partition function since the deformed action can be written as a δϵ\delta_\epsilon-exact form. The critical points of the deformed action turn out to be the space of flat connections which are, in fact, zero modes of the gauge field. The one-loop evaluation over the space of flat connections reduces to the matrix integral by which the N=4{\cal N}=4 superconformal index is expressed.Comment: 42+1 pages, 2 figures, JHEP style: v1.2.3 minor corrections, v4 major revision, conclusions essentially unchanged, v5 published versio

    Forecast-Founded Haze Bandwidth And Cost Decrease Scheme

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    In last couple of years there huge increase in the usage cloud computing because cloud computing is emerging style of IT-delivery in which applications, data and resources are rapidly provisioned provided as standardized offerings to users with a flexible price. But it is important to provide the convenient pricing model for the users of cloud. Hence we design a new traffic redundancy and elimination scheme for reducing the cloud bandwidth and costs. Cloud computing is a fast growing field which is arguably a new computing paradigm. In cloud computing, computing resources are provided as services over the internet and users can access resources by paying. When we are trying to minimize the cloud cost, transmission cost plays a major role. In this paper, we present PACK (Predictive ACKs) mechanism, a novel end-to-end traffic redundancy elimination (TRE) system, designed for cloud computing customers. During this     paper we provide a survey on the new traffic redundancy technique called novel-TRE conjointly called receiver based TRE. This novel-TRE has important options like detective work the redundancy at the customer, randomly rotating appear chained, matches incoming chunks with a antecedently received chunk chain or native file and sending to the server for predicting the long run information and no would like of server to unceasingly maintain consumer state

    A note on the integral equation for the Wilson loop in N = 2 D=4 superconformal Yang-Mills theory

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    We propose an alternative method to study the saddle point equation in the strong coupling limit for the Wilson loop in N=2\mathcal{N}=2 D=4 super Yang-Mills with an SU(N) gauge group and 2N hypermultiplets. This method is based on an approximation of the integral equation kernel which allows to solve the simplified problem exactly. To determine the accuracy of this approximation, we compare our results to those obtained recently by Passerini and Zarembo. Although less precise, this simpler approach provides an explicit expression for the density of eigenvalues that is used to derive the planar free energy.Comment: 12 pages, v2: section 2.5 (Free Energy) amended and reference added, to appear in J. Phys.

    Superconformal indices of three-dimensional theories related by mirror symmetry

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    Recently, Kim and Imamura and Yokoyama derived an exact formula for superconformal indices in three-dimensional field theories. Using their results, we prove analytically the equality of superconformal indices in some U(1)-gauge group theories related by the mirror symmetry. The proofs are based on the well known identities of the theory of qq-special functions. We also suggest the general index formula taking into account the U(1)JU(1)_J global symmetry present for abelian theories.Comment: 17 pages; minor change

    Eco-friendly and versatile brominating reagent prepared from a liquid bromine precursor

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    Facile bromination of various organic substrates has been demonstrated with a 2 : 1 bromide:bromate reagent prepared from the alkaline intermediate of the conventional bromine recovery process. The reagent is acidified in situ to generate HOBr as the reactive species, which effects bromination. Aromatic substrates that have been successfully brominated under ambient conditions without use of any catalyst include phenols, anilines, aromatic ethers and even benzene. Non-aromatic compounds bearing active methylene group were monobrominated selectively with the present reagent and olefinic compounds were converted into the corresponding bromohydrins in moderate yields. By obtaining the present reagent from the liquid bromine precursor, the twin advantages of avoiding liquid bromine and producing the reagent in a cost-effective manner are realised. When coupled with the additional advantage of high bromine atom efficiency, the present protocol becomes attractive all the way from "cradle to grave"
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