In this paper we investigate a seamless method for the adaptation of streamed media by using simultaneous processing chains. the common approach for media adaptation is to deconstruct the current media processing chai...
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ISBN:
(纸本)9781581136203
In this paper we investigate a seamless method for the adaptation of streamed media by using simultaneous processing chains. the common approach for media adaptation is to deconstruct the current media processing chain and to construct a new media chain afterwards. As a consequence, media frames might be lost and the adaptation cycle needs significant time. In our approach, the new processing chain is built in parallel to the current one and the stream is switched to the new chain as soon as possible. Withthis mechanism, we can guarantee zero-loss behaviour in the sender, and at the same time, reduce the overall adaptation time significantly. the proposed method is independent of the actual codec and can be applied to both audio and video streams. We present a formal calculation of the possible improvements of our proposed mechanism with respect to information loss and adaptation speed and also report about results obtained in our implementation using the Java Media Framework.
We demonstrate the stepwise fabrication of parallel double quantum dots in GaAs/AlGaAs-heterostructures. the atomic force microscope serves as a direct lithographic tool for the processing of our samples, the devices ...
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We demonstrate the stepwise fabrication of parallel double quantum dots in GaAs/AlGaAs-heterostructures. the atomic force microscope serves as a direct lithographic tool for the processing of our samples, the devices are characterized by transport measurements. Coulomb-blockade oscillations and diamonds with different periods for the two quantum dots are observed. (C) 2002 Elsevier Science B.V, All rights reserved.
Heterogeneous parallel systems are becoming increasingly more common, especially withthe increasing use of cluster computers, such as PCs and networks of workstations for parallel computing. the main concern of this ...
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Heterogeneous parallel systems are becoming increasingly more common, especially withthe increasing use of cluster computers, such as PCs and networks of workstations for parallel computing. the main concern of this paper is measuring and evaluating the performance of such parallel systems, based on a dynamic load balancing algorithm for the parallel search algorithm: a depth-first search algorithm. the implementation of dynamic load balancing is running under the message passing interface that allows parallel execution on the cluster of heterogeneous 6 SUN workstations, operating withthe Solaris operating system and a cluster of 10 PCs operating withthe Linux operating system, the parallel program of dynamic load balancing is written in C language.
作者：
Li, YPYanshan Univ
Dept Mech Engn Qinhuangdao 066004 Peoples R China
Some problems existing in present grinding machines areanalyzed, and anew type of CNC grinding machine is presented. As the feed system of this grinding machine is a parallel mechanism driven directly by linear motors...
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Some problems existing in present grinding machines areanalyzed, and anew type of CNC grinding machine is presented. As the feed system of this grinding machine is a parallel mechanism driven directly by linear motors, some traditional transmission forms are notrequired, such as the ball lead screw pairs, the gears, the hydraulic transmission device, etc. A complex space trajectory of the emery wheel can be achieved, and high accuracy feeding and positioning of the emery wheel can be accomplished with an open-loop control system only. High grinding speed and stepless speed variation can be achieved because of the spindle being driven directly by a non-frame motor. Not only complex work-pieces of high hardness or low hardness materials, but also complex work-pieces of hard-to-machine materials are suitable to be ground by this grinding machine. (C) 2002 Elsevier Science B.V. All rights reserved.
作者：
Li, YPYanshan Univ
Dept Mech Engn Qinhuangdao 066004 Peoples R China
Some problems existing in present grinding machines areanalyzed, and anew type of CNC grinding machine is presented. As the feed system of this grinding machine is a parallel mechanism driven directly by linear motors...
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Some problems existing in present grinding machines areanalyzed, and anew type of CNC grinding machine is presented. As the feed system of this grinding machine is a parallel mechanism driven directly by linear motors, some traditional transmission forms are notrequired, such as the ball lead screw pairs, the gears, the hydraulic transmission device, etc. A complex space trajectory of the emery wheel can be achieved, and high accuracy feeding and positioning of the emery wheel can be accomplished with an open-loop control system only. High grinding speed and stepless speed variation can be achieved because of the spindle being driven directly by a non-frame motor. Not only complex work-pieces of high hardness or low hardness materials, but also complex work-pieces of hard-to-machine materials are suitable to be ground by this grinding machine. (C) 2002 Elsevier Science B.V. All rights reserved.
the external selection problem is to select the record withthe K-th smallest key from the given N records that are distributed and stored evenly on the D disks for the parallel machine with D processors. Each process...
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ISBN:
(纸本)0769515126
the external selection problem is to select the record withthe K-th smallest key from the given N records that are distributed and stored evenly on the D disks for the parallel machine with D processors. Each processor has its own primary memory of size M records and one disk, where N/D>M. the processors are connected with a /spl radic/D /spl times/ /spl radic/D mesh architecture. Based on a two-stage approach, this paper presents an efficient parallel external selection algorithm for the distributed-memory parallel systems. First, all the processors execute local external sorting in parallel, each processor sorts the N/D records on its own disk. Next, they execute parallel external selection from the D sorted sub-files on the D disks. this algorithm is asymptotically optimal and has a small constant factor of time complexity.
the proceedings contain 70 papers. the special focus in this conference is on High Performance Computing. the topics include: High-performance computing and visualization;2-d wavelet transform enhancement on general-p...
ISBN:
(纸本)3540003037
the proceedings contain 70 papers. the special focus in this conference is on High Performance Computing. the topics include: High-performance computing and visualization;2-d wavelet transform enhancement on general-purpose microprocessors;a general data layout for distributed consistency in data parallel applications;duplication-based scheduling algorithm for interconnection-constrained distributed memory machines;evaluating arithmetic expressions using tree contraction;a mechanism to reduce i-cache power consumption in high performance microprocessors;exploiting web document structure to improve storage management in proxy caches;high performance multiprocessor architecture design methodology for application-specific embedded systems;a low latency messaging infrastructure for Linux clusters;low-power high-performance adaptive computing architectures for multimedia processing;a technique to construct high performance CORBA applications;automatic search for performance problems in parallel and distributed programs by using multi-experiment analysis;an adaptive value-based scheduler and its RT-Linux implementation;effective selection of partition sizes for moldable scheduling of parallel jobs;runtime support for multigrain and multiparadigm parallelism;a fully compliant openMP implementation on software distributed shared memory;a fast connection-time redirection mechanism for internet application scalability;an efficient resource sharing scheme for dependable real-time communication in multihop networks;improving web server performance by network aware data buffering and caching;wraps scheduling and its efficient implementation on network processors;performance comparison of pipelined hash joins on workstation clusters and iterative algorithms on heterogeneous network computing.
Reconfigurable architectures represent an innovative approach to the computer system design paradigm, which tries to cope with a problem of inefficiency of conventional computing systems, due to their general purpose ...
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ISBN:
(纸本)0769514448
Reconfigurable architectures represent an innovative approach to the computer system design paradigm, which tries to cope with a problem of inefficiency of conventional computing systems, due to their general purpose nature. On the other hand, cellular automata are attractive computing models due to their fine grain parallelism, simple computational structures and local communication patterns. the inherently parallel cellular automata model is well suited to be implemented on reconfigurable hardware architectures such as field programmable gate arrays (FPGA) that can provide significant speedup. this paper describes the CAREM system that provides an efficient implementation of cellular automata algorithms on FPGA systems exploiting their reconfigurable features for executing different cellular automata rules. Its application to an image processing application and a forest fire simulation are presented and discussed. Performance evaluation and comparison with different implementations of cellular automata are presented.
In this paper, Hamming distance is used to control individual difference in the process of creating an original population, and a peak-depot is established to preserve information of different peak-points. Some new me...
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In this paper, Hamming distance is used to control individual difference in the process of creating an original population, and a peak-depot is established to preserve information of different peak-points. Some new methods are also put forward to improve the optimization performance of a genetic algorithm (GA), such as the point-cast method and the neighborhood search strategy around peak-points. the methods, are used to deal with genetic operation as well as cross-over and mutation, in order to obtain a global optimum solution and avoid the GAs premature convergence. By means of many control rules and a peak-depot, the new algorithm carries out an optimum search surrounding several peak-points. Along withthe evolution of individuals of the population, the fitness of peak-points of peak-depot increases continually, and a global optimum solution can be obtained. the new algorithm searches around several peak-points, which increases the probability of obtaining the best global optimum solution. the results of some examples to test the modified GA indicate that what has been done makes the modified genetic algorithm effective in solving both linear optimization problems and non-linear optimization problems with restrictive functions. (C) 2002 Elsevier Science B.V. All rights reserved.
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