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Bandwidth Borrowing Schemes for Instantaneous Video-on-Demand Systems
A controlled multicast scheme provides instantaneous service, but limited server bandwidth causes some user requests to be either delayed or rejected when insufficient free bandwidth is available. Two borrowing schemes are proposed for instantaneous video-on-demand (VOD) that reduce the user request blocking rate by borrowing bandwidth from ongoing video streams when there is insufficient free bandwidth for the server to deliver a new video stream. Both these new schemes have proved to be successful in reducing blocking rate and increasing bandwidth utilization at the expense of temporarily degrading the video quality
An Indictment of Bright Line Tests for Honest Services Mail Fraud
Sparse matrix-matrix multiplication (SpGEMM) is a computational primitive that is widely used in areas ranging from traditional numerical applications to recent big data analysis and machine learning. Although many SpGEMM algorithms have been proposed, hardware specific optimizations for multi- and many-core processors are lacking and a detailed analysis of their performance under various use cases and matrices is not available. We firstly identify and mitigate multiple bottlenecks with memory management and thread scheduling on Intel Xeon Phi (Knights Landing or KNL). Specifically targeting multi- and many-core processors, we develop a hash-table-based algorithm and optimize a heap-based shared-memory SpGEMM algorithm. We examine their performance together with other publicly available codes. Different from the literature, our evaluation also includes use cases that are representative of real graph algorithms, such as multi-source breadth-first search or triangle counting. Our hash-table and heap-based algorithms are showing significant speedups from libraries in the majority of the cases while different algorithms dominate the other scenarios with different matrix size, sparsity, compression factor and operation type. We wrap up in-depth evaluation results and make a recipe to give the best SpGEMM algorithm for target scenario. A critical finding is that hash-table-based SpGEMM gets a significant performance boost if the nonzeros are not required to be sorted within each row of the output matrix
Similarities Between Classical Timelike Geodesics in a Naked Reissner-Nordstrom Singularity Background and the Behaviour of Electrons in Quantum Theory
It is generally assumed that naked singularities must be physically excluded,
as they could otherwise introduce unpredictable influences in their future null
cones. Considering geodesics for a naked Reissner-Nordstrom singularity, it is
found that the singularity is effectively clothed by its repulsive nature.
Regarding electron as naked singularity, the size of the clothed singularity
(electron) turns out to be classical electro-magnetic radius of the electron,
to an observer falling freely from infinity, initially at rest. The size
shrinks for an observer falling freely from infinity, with a positive initial
velocity. For geodetic parameters corresponding to negative energy there are
trapped geodesics. The similarity of this picture with that arising in the
Quantum Theory is discussed.Comment: 8 pages, 6 figure
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An empirical analysis of the factors affecting bank crises in Japan : learning points for Bangladesh
This paper analyzes the factors that affect bank crises in Japan. There are numerous factors, qualitative and quantitative, identified from the analysis. For the quantitative analysis, the study employs the factor analysis, which detects three major components of factors that affect banking or financial crises in Japan. These are (i) common macro factors; (ii) bank sensitive micro factors; and (iii) household spending related factors. There are other factors, for example, policy dilemma, delayed or faulty deregulation measures and weak banking activities, which are not extracted from the factor analysis but adversely affect bank crises in Japan and hence discussed in details. The paper indicates some policy implications for the banking/financial sector of Bangladesh
On homogeneous CR manifolds and their CR algebras
In this paper we show some results on homogeneous CR manifolds, proved by
introducing their associated CR algebras. In particular, we give different
notions of nondegeneracy (generalizing the usual notion for the Levi form)
which correspond to geometrical properties for the corresponding manifolds. We
also give distinguished equivariant CR fibrations for homogeneous CR manifolds.
In the second part of the paper we apply these results to minimal orbits for
the action of a real form of a semisimple Lie group \^G on a flag manifold
\^G/Q.Comment: 14 pages. AMS-LaTeX v2: minor revisio
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