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991.
针对目前应用在UNIX系统中入侵检测知识库适应能力不足的问题.提出了一种适应于不同系统环境的知识库体系结构。检测规则按相应系统与服务类型以模块化形式存储,通过应用配制文件加载。实现了入侵检测知识库的可扩展性.提高了入侵检测知识库的通用性,并且可以提高检测规则的搜索效率。 相似文献
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Dynamic neural networks with different time-scales include the aspects of fast and slow phenomenons. Some applications require
that the equilibrium points of the designed networks are stable. In this paper, the passivity-based approach is used to derive
stability conditions for dynamic neural networks with different time-scales. Several stability properties, such as passivity,
asymptotic stability, input-to-state stability and bounded input bounded output stability, are guaranteed in certain senses.
A numerical example is also given to demonstrate the effectiveness of the theoretical results. 相似文献
995.
December th is the fifth anniversary of China's entry into WTO. Over the past five years what AQSIQ has done in implementing the obligations enjoying the rights as a member of WTO? How's the performance? Facing with the current complicated barrier of technology trade worldwide how will China reply to it? For these questions reporters have made a special interview with Li Changjiang Minister of AQSIQ.…… 《中国标准化(英文版)》2007,(1):2-7
December 11th, 2006 is the fifth anniversary of China's entry into WTO. Over the past five years, what AQSIQ has done in implementing the obligations and enjoying the rights as a member of WTO? How's the performance? Facing with the current complicated barrier of technology trade worldwide, how will China reply to it? For these questions, reporters have made a special interview with Li Changjiang, Minister of AQSIQ. 相似文献
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997.
998.
New bottle but old wine: A research of cyberbullying in schools 总被引:1,自引:0,他引:1
This study investigates the nature and the extent of adolescences’ experience of cyberbullying. A survey study of 177 grade seven students in an urban city is conducted. In this paper, “cyberbullying” refers to bullying via electronic communication tools. The results show that almost 54% of the students were victims of traditional bullying and over a quarter of them had been cyber-bullied. Almost one in three students had bullied others in the traditional form, and almost 15% had bullied others using electronic communication tools. Almost 60% of the cyber victims are females, while over 52% of cyber-bullies are males. Majority of the cyber-bully victims and bystanders did not report the incidents to adults. 相似文献
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Intensive use of phosphates has resulted in high P levels in surface waters and therefore eutrophication problems. Over the last decade many studies have revealed the advantage of using specific materials with efficient phosphorus retention capacities. Recent studies state that Ca materials are of particular interest for long-term retention of P, but can induce negative effects. To improve P retention and avoid negative counter-effects we tested the potential of natural apatites. Apatite sorption was evaluated using batch and open reactor experiments. Batch experiments identify sorption mechanisms and the influence of the ionic characteristics of the solution; open reactor experiments evaluate sorption capacities in relation to the ionic composition of the solution and biomass development. In parallel, observation of the material by electron microscopy was used to give more precision information about the mechanisms involved. This work reveals the strong chemical affinity between apatites and phosphorus. Compared to other calcareous materials apatite is better able to maintain low outlet P levels. After more than 550 days feeding, sorption was still present and low P outlet levels were still being obtained when sufficient contact time and calcium content in the solution were ensured. This work demonstrates the advantages of using apatites for phosphorus removal in constructed wetlands. The behaviour of apatite in phosphorus retention is explained and its suitability for use in such extensive systems defined. 相似文献