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针对舰艇编队作战系统的复杂性和易变性,分析了可扩展标记语言XML在分布交互作战仿真系统中的数据表示、传输、处理等方面的特点,给出了不同形式舰艇编队仿真系统想定文件的统一XML表示形式.介绍了在HLA/RTI仿真体系结构下,应用XML进行仿真数据管理的基本方法,实现了一种基于XML数据标准的分布交互仿真支撑框架体系结构.所讨论的内容已经在舰艇编队作战仿真系统中实现,为类似系统的开发提供了可借鉴的开发原型. 相似文献
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异构无线分组网络中的接入选择机制 总被引:1,自引:0,他引:1
传统多接入选择(Multi-Radio Access Selection)方法只针对话音业务,在设计中仅仅考虑已接入用户数及系统容量,由于未将"分组级"信息考虑在内而不适用于无线分组网络。提出了一种新的异构无线分组网络中的接入选择算法,分组业务在多接入选择时考虑了实时、非实时的不同QoS要求和链路自适应机制(链路层重传及自适应调制编码);用户接入后,在保证其QoS的基础上,同时达到不同网络间负载均衡的目的。基于OPNET Modeler的动态仿真对算法性能进行了仿真评估,并与传统的最小用户数和最小路径损耗多接入选择方法在保证业务QoS和负载均衡性能方面进行了比较。 相似文献
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Tomohiko SAKAO Nicola NAPOLITANO Massimo TRONCI Erik SUNDIN Mattias LINDAHL 《系统科学与系统工程学报(英文版)》2008,17(3):367-381
A new business concept that offers products and services in a different way of traditional product-sales businesses is getting more attention especially in manufacturing industries. This paper investigates how this new business by means of integration of products and services is achieved in Germany and Italy. In addition, it analyzes the differences according to the company sizes. The results include that this type of business is in many cases motivated by their focus on customers and often consists of physical products and their maintenance. The Italian companies, as opposed to the German ones, often design their physical products specifically for this type of offers. From the analysis based on the size difference, small companies are found to achieve specific design for this type of offers while owning physical products. There do not seem to be any established methods or tools developed to support the development of such offers and within such methods/tools there would be room for more adaptation in form of physical product design. 相似文献
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Automatic patent document summarization for collaborative knowledge systems and services 总被引:1,自引:0,他引:1
Engineering and research teams often develop new products and technologies by referring to inventions described in patent
databases. Efficient patent analysis builds R&D knowledge, reduces new product development time, increases market success,
and reduces potential patent infringement. Thus, it is beneficial to automatically and systematically extract information
from patent documents in order to improve knowledge sharing and collaboration among R&D team members. In this research, patents
are summarized using a combined ontology based and TF-IDF concept clustering approach. The ontology captures the general knowledge
and core meaning of patents in a given domain. Then, the proposed methodology extracts, clusters, and integrates the content
of a patent to derive a summary and a cluster tree diagram of key terms. Patents from the International Patent Classification
(IPC) codes B25C, B25D, B25F (categories for power hand tools) and B24B, C09G and H011 (categories for chemical mechanical
polishing) are used as case studies to evaluate the compression ratio, retention ratio, and classification accuracy of the
summarization results. The evaluation uses statistics to represent the summary generation and its compression ratio, the ontology
based keyword extraction retention ratio, and the summary classification accuracy. The results show that the ontology based
approach yields about the same compression ratio as previous non-ontology based research but yields on average an 11% improvement
for the retention ratio and a 14% improvement for classification accuracy. 相似文献
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Jiang Zhang 《系统科学与复杂性》2009,22(3):345-359
Energy flow drives the complex systems to evolve. The allometric scaling as the universal energy flow pattern has been found
in different scales of ecological systems. It reflects the general power law relationship between flow and store. The underlying
mechanisms of energy flow patterns are explained as the branching transportation networks which can be regarded as the result
of systematic optimization of a biological target under constraints. Energy flows in the ecological system may be modelled
by the food web model and population dynamics on the network. This paper reviews the latest progress on the energy flow patterns,
explanatory models for the allometric scaling and modelling approach of flow and network evolution dynamics in ecology. Furthermore,
the possibility of generalizing these flow patterns, modelling approaches to other complex systems is discussed.
This research is supported by Guozhi Xu Post Doctoral Research Foundation and the National Natural Science Foundation of China
under Grant No. 60574068. 相似文献
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