46240388
An Efficient Heuristic Algorithm for Constructing Delay- and Degree-Bounded Application-Level Multicast Tree
In this paper we first investigate the problem of finding a delay- and degree-bounded maximum sum of nodes ALMT. We proved the problem is NP-hard, and testify its relationship with the well-studied degree-bounded minimum maximum-delay ALMT problem. We proposed a greedy algorithm FindOverlayTree with SRPF heuristic. The simulation results show that our design solution is a valid and cost-effective approach where compared to other three modified classic heuristics under several performance metrics.
15977207
Exploiting hierarchical CP-nets to increase the reliability of Web services workflow
Individual Web services can be composed together to form value-added composite Web services represented as business process workflow. However, the value of such composite Web services is directly influenced by the reliability of the composite services. Composing Web services is not an easy task and is error-prone, so there is a growing interest for the verification techniques which enable designers to find and repair design errors even before actual running of the service, or allow designers to detect erroneous properties such as deadlocks or livelocks and formally verify whether the service process design does have certain desired properties (such as consistency with the conversation protocols of partner service). In this paper, we present to analyze and verify Web services composition by using some kind of colored Petri nets (CP-nets) called hierarchical CP-nets, which combine the strengths of Petri nets with the expressive power of high-level programming and have sound mathematical semantics. Services composition proposals can be transformed by transformation rules into CP-nets, which can be simulated to analyze the performance and verified to investigate behavioral properties by exploiting existing CP-nets specialized tools
33185687
Supremum of Agent Number Needed in Analyzing Security Protocols Based on Horn Logic
12282317
A note on “a mapping algorithm for computer-assisted exploration in the design of embedded systems”
The scaling of autoclave and leaching-equipment surfaces during the high pressure leaching of nickeliferous oxide and silicate ores is controlled during leaching to favor the formation of scale containing substantial amounts of magnesium sulfate that is more easily removed by chemical dissolution using water or dilute sulfuric acid at temperatures ranging from about 50 DEG C. to 250 DEG C. than scale containing substantial amounts of alunite.
28489429
Transmission Scheduling in Data-Driven Peer-to-Peer Streaming towards Optimal Throughput
Peer-to-peer media streaming has been an important service on the internet in recent years. The Data-driven (or mesh-based) structure is adopted by most working systems,in which data scheduling is one of the important problems.However, those frequently used scheduling algorithms are often faced with such a case: A neighbor peer takes up its bandwidth to deliver the packets that other neighbors can also supply, but some packets only held by it are not delivered.These packets can not be delivered in the current scheduling cycle, even though that the other neighbors have surplus bandwidth. This is a kind of waste of bandwidth and decreases the throughput of transmission. In this paper we propose anew scheduling algorithm aiming at the optimal throughput:Bipartite-matching based Block Scheduling algorithm(BBS).We convert the original data scheduling problem to a problem of finding a maximum match on the correspond bipartite graph, then assign data packets to neighbors according to the maximum match. We evaluate the performance of BBS with extensive experiments and the results show that BBS throughput and provides better streaming quality than those frequently used scheduling algorithms.
6983597
A Comparative Study of Parallel Prefix Adders in FPGA Implementation of EAC
Several regular parallel trees have been proposed over the years to optimize logic depth, area, fan-out and in- terconnect count for logic circuits. In this paper, we propose a comparative study of different parallel prefix trees used in the design of a new end-around carry (EAC) adder targeting FPGA technology. This new adder is based on the fast 128-bit binary floating-point EAC adder which has been implemented in the IBM POWER6 microprocessor's fused multiply-add unit. The parallel prefix tree implemented on the IBM's EAC adder is a Kogge-Stone tree which has been chosen for its high performance and its low power consumption. Our comparative study highlights the main performance differences among fourteen different architecture configurations when targeting an FPGA EAC adder design. We focus on the area requirements and the critical path delay of these designs. Our experimental results show that there is one architecture configuration with the lower area requirement and the higher performance.
11689877
A Projection and Search Algorithm for the Bicluster Problem
The advent of microarray technologies has made the experimental study of gene expression faster and more efficient. It is an important task to analyze the gene expression data acquired from the microarray experiments. Biclustering is a popular method to search a subset of genes which exhibit similar expression patterns along a subset of conditions in the gene expression matrix. In this paper, we propose a projection and search algorithm (PSA) for finding biclusters in the gene expression matrix. The algorithm adopts projection method to find a raw submatrix, then refines and extends the raw submatrix into a bicluster using greedy algorithms. We test the algorithm on simulation data and real data. The test results show that the algorithm has good performance on both simulation data and real data. Additionally, compared with other methods, PSA isnpsilat sensitive to noise level.
29221183
Intelligent Crowd Simulation
Crowd simulation is a continuous challenge in computer animation. In this paper, we present an intelligent crowd simulation technique based on multiple autonomous agents. Each animated character (AC) is modeled as an autonomous agent, consisting of the perception, behavior planning and motion generation system. AC perceives the environment information, generates intentions and plans behaviors autonomously. To execute behaviors, appropriate motions are selected from the fundamental motion library (FML) and edited to create required motions. And the crowd behavior can be regarded as a combination of the individual behavior of each AC. The experiment shows the feasibility of this technique.
10172928
Texture-Consistent Shadow Removal
This paper presents an approach to shadow removal that preserves texture consistency between the original shadow and lit area. Illumination reduction in the shadow area not only darkens that area, but also changes the texture characteristics there. We achieve texture-consistent shadow removal by constructing a shadow-free and texture-consistent gradient field. First, we estimate an illumination change surface which causes the shadow and remove the gradients it induces. We approximate the illumination change surface with illumination change splines across the shadow boundary. We formulate estimating these splines as an optimization problem which balances the smoothness between the neighboring splines and their fitness to the image data. Second, we sample the shadow effect on the texture characteristics in the umbra and lit area near the shadow boundary, and remove it by transforming the gradients inside the shadow area to be compatible with the lit area. Experiments on photos from Flickr demonstrate the effectiveness of our method.
1077673
Low Complexity MMSE Vector Precoding Using Lattice Reduction for MIMO Systems
In this paper, a lattice-reduction-aided (LRA) minimum mean square error (MMSE) vector precoding (VP) is proposed for multiple input multiple output (MIMO) systems. Three schemes are provided for the perturbation vector design by Babai's approximation procedures based on lattice reduction method to reduce the complexity. Performance and complexity analysis are provided. Simulation results show that the proposed schemes significantly outperform the conventional MMSE Tomlinson-Harashima precoding (THP) and the zero forcing (ZF) VP. Compared with the MMSE VP via closest-point search, our LRA approach provides a simple alternative with little performance loss.
3230690
A new verification-based fast-match for large vocabulary continuous speech recognition
Acoustic fast-match is a popular way to accelerate the search in large-vocabulary continuous-speech recognition, where an efficient method is used to identify poorly scoring phonemes and discard them from detailed evaluation. In this paper we view acoustic fast-match as a verification problem, and hence develop an efficient likelihood ratio test, similar to other verification scenarios, to perform the fast match. Various aspects of the test like the design of alternate hypothesis models and the setting of phoneme look-ahead durations and decision thresholds are studied, resulting in an efficient implementation. The proposed fast-match is tested in a large vocabulary speech recognition task and it is demonstrated that depending on the decision threshold, it leads to 20-30% improvement in speed without any loss in recognition accuracy. In addition, it significantly outperforms a similar test based on using likelihoods only, which fails, in our setting, to bring any improvement in speed-accuracy trade-off. In a larger set of experiments with varying acoustic and task conditions, similar improvements are observed for the fast-match with the same model and setting. This indicates the robustness of the proposed technique. The gains due to the proposed method are obtained within a highly efficient 2-pass search strategy and similar or even higher gains are expected in other alternative search architectures.