A new heuristic density-based ant colony clustering algorithm (HDACC) is presented. The device of memory bank is first proposed, which brings forth the heuristic knowledge guiding ant to move in the bi-dimensional gri...
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A new heuristic density-based ant colony clustering algorithm (HDACC) is presented. The device of memory bank is first proposed, which brings forth the heuristic knowledge guiding ant to move in the bi-dimensional grid space. In this way, the algorithm's convergence is speeded up and the appearance of un-assigned data object avoided, and the error rate in classification drops subsequently. A density-based method is then proposed permitting each ant to look ahead and reduces the number of times in region-inquiry. Consequently the clustering time is saved. Some experiments were made on real and synthetic date sets. Experimental results were comp.red with those obtained using other classical clustering algorithms. The results demonstrated that the proposed HDBCSI is a viable and effective clustering algorithm.
Based on distributed performance enhancing proxies, a new transport protocol for the satellite environment, the XP protocol is presented. It is designed and optimized to overcome the performance degradation that TCP e...
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Based on distributed performance enhancing proxies, a new transport protocol for the satellite environment, the XP protocol is presented. It is designed and optimized to overcome the performance degradation that TCP experiences in satellite networks due to their long latency, high bit error rate, and bandwidth asymmetry characteristics. Main contributions include a reliable two-and-half-way handshake connection establishment mechanism, rate control and a measurement-based adaptive bandwidth allocation algorithm, and a delayed acknowledgements technique based on active sender-request. Interactions with the TCP connections in terrestrial segments are also considered. Emulation and real operating environment experiments show that the throughputs achieved by XP improve substantially in comp.rison with the regular TCP, and the fairness is also maintained perfectively when the bandwidth is shared among multi-connections.
Accurate and timely predictions of airline pushbacks can potentially lead to improved management of airport surface traffic, including reductions in the variability and average duration of costly airline delays. One f...
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Conventional comp.ter network management systems provide a virtual network view, which can not reflect the actual distribution in the space of networks. Applying geographical information system (GIS) to network monito...
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Conventional comp.ter network management systems provide a virtual network view, which can not reflect the actual distribution in the space of networks. Applying geographical information system (GIS) to network monitor and management system, an intuitional interface can be given that facilitates the management. A GIS-based comp.ter network hierarchical model is proposed to solve the problem how effectively integrate GIS and network topology, network status information together. Accordingly the model related creation, maintenance, operation algorithms are proposed. And then the model is applied to a distributed network performance monitoring and on-line analysis system, NIPMAS.
An approach to constructing service-oriented and event-driven application dynamic alliance is brought forward to cope with dynamic selection and self-determinedly joining of partners in constructing and operating dyna...
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An approach to constructing service-oriented and event-driven application dynamic alliance is brought forward to cope with dynamic selection and self-determinedly joining of partners in constructing and operating dynamic alliances. In the paper, a publish/subscribe based business event processing mechanism and a partner negotiation mechanism are introduced to enrich Service-oriented Architecture. The fundamental concepts, such as business event, event processing, event subscription, business collective and dynamic alliance, are discussed first. Working principle of the approach, subscription information based partner discovery algorithms and negotiation aided partner selection are discussed thereafter. Guided by the approach and supported by the commercially available JMS and Message Queue service, a dynamic supply chain management system for an electronics manufacturing corporation is implemented.
More and more academic researchers and people from industry are engaged in developing wireless sensor networks due to the great promise and potential with various applications. This paper describes the basic concept a...
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More and more academic researchers and people from industry are engaged in developing wireless sensor networks due to the great promise and potential with various applications. This paper describes the basic concept and hardware platform for sensor network. Then the network protocol architecture is proposed with brief introduction of each individual research issue involved. Detailed progress in a few most important research areas is also discussed, including data link layer protocol, network layer routing protocol, power management and network simulation tool.
Abstractions are important in specifying and proving properties of comp.ex systems. To prove that a given automaton implements an abstract specification automaton, one must first find the correct abstraction relation ...
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Combining spatial layered coding with fine granularity scalability coding techniques, an algorithm of spatial fine granularity scalable coding (S-FGS) is proposed. It provides high adaptability to network bandwidth, d...
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Combining spatial layered coding with fine granularity scalability coding techniques, an algorithm of spatial fine granularity scalable coding (S-FGS) is proposed. It provides high adaptability to network bandwidth, does not reduce the comp.ession ratio and retains quality of reconstructed images. Based on this algorithm, a coding system model is proposed for still image data comp.ession. Experimental results show that the time comp.exity of the algorithm is mainly affected by scalable granularity, and the algorithm is viable with specific granularity setting.
Text categorization (TC) is an important research direction in Text Mining. It aims to assign one or more predefined category label(s) for a text document, and provides efficient methods for documents management and i...
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Text categorization (TC) is an important research direction in Text Mining. It aims to assign one or more predefined category label(s) for a text document, and provides efficient methods for documents management and information searching. A major problem in automatic text categorization is how to select the best feature subset from the original high feature space in order to make the categorization algorithm work efficiently and improve the precision. In this paper, the methods of feature selection and weight adjustment techniques are discussed and analyzed, and their influence on text classification precision and efficiency is pointed out. Furthermore, the TEF-WA (term evaluation function-weight adjustment) is introduced. We introduce a new weight function, which includes feature weight evaluation function and adjusts the effect of the feature term in the classifier according to the feature term's strength. To evaluate the TEF-WA method, experiments are carried by using several different scale training document collection, various term evaluation functions such as document frequency, information gain, expected cross entropy, CHI, the weight of evidence for text, term frequency formula or document frequency formula. The experiment results have proved that the TEF-WA technique is efficient in promoting the classification precision and reducing the comp.te comp.exity.
For the dimensions sparseness of the text set, a new similarity search algorithm for text set is proposed, which is based on inverted-index. The algorithm can quickly gain a super-set for the targets by search on inve...
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For the dimensions sparseness of the text set, a new similarity search algorithm for text set is proposed, which is based on inverted-index. The algorithm can quickly gain a super-set for the targets by search on inverted-index. Experiments show that the algorithm is faster than the algorithm based on multi-dimension index for huge text set, while a little nicety losing.
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