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排序方式: 共有4293条查询结果,搜索用时 31 毫秒
71.
许松 《数字社区&智能家居》2009,5(7):5191-5192,5207
该文提出了利用P2P网络技术构建网络教学平台的设想,简要介绍了当前的P2P技术,分析了其技术优势,设计了一个基于混合式P2P网络的网络教学平台模型,并深入讨论了系统实现几个关键问题,提出了解决方案。 相似文献
72.
73.
基于混合型防火墙与入侵检测技术的联合网络防御系统研究 总被引:1,自引:0,他引:1
乜国雷 《自动化与仪器仪表》2009,(5):133-134,143
随着计算机网络的不断发展,保护网络中的信息免受各种攻击为根本目的网络安全变得越来越重要。系统地分析了混合型防火墙技术及入侵检测相关技术,并提出了基于两种技术的联合网络防御系统。 相似文献
74.
Internet拥塞控制系统在不同源控制算法作用下的资源竞争分析 总被引:1,自引:1,他引:0
在未来的Internet拥塞控制协议中,不同的用户群根据不同的QoS需求,可以实现不同的控制算法.系统地研究了拥塞控制系统在AIMD和MIMD两类源算法共同作用下的稳态和动态特性,这些特性揭示了配置不同源控制算法的用户群对网络资源的竞争.内容包括AIMD,MIMD算法共同作用下的系统模型、系统稳态分析、系统稳定性分析等.基于NS2系统的仿真结果,证实了给出的分析方法的有效性,并揭示了不同源算法对网络资源的竞争情况. 相似文献
75.
76.
Dimitrios Tzovaras Konstantinos Moustakas Georgios Nikolakis Michael G. Strintzis 《Personal and Ubiquitous Computing》2009,13(1):51-58
This paper presents a mixed reality tool developed for the training of the visually impaired based on haptic and auditory
feedback. The proposed approach focuses on the development of a highly interactive and extensible Haptic Mixed Reality training
system that allows visually impaired to navigate into real size Virtual Reality environments. The system is based on the use
of the CyberGrasp™ haptic device. An efficient collision detection algorithm based on superquadrics is also integrated into
the system so as to allow real time collision detection in complex environments. A set of evaluation tests is designed in
order to identify the importance of haptic, auditory and multimodal feedback and to compare the MR cane against the existing
Virtual Reality cane simulation system. 相似文献
77.
《Displays》2023
As a comprehensive integration of many new-generation information technologies, the metaverse has become a research hotspot that has attracted much attention. As a part of the metaverse, the industrial metaverse is expected to break through the constraints of space and time and promote high-quality industrial development. The industrial metaverse is human-centric, so its quality of experience (QoE) is a key topic. As one of the enabling technologies of the industrial metaverse, Mixed Reality (MR) can seamlessly integrate virtual information with the physical world and is widely regarded as an important window to the industrial metaverse. In close integration with other enabling technologies, industrial MR applications can be seen as a path toward the realization of the industrial metaverse; thus, the optimization of industrial MR applications can effectively achieve the QoE enhancement of the industrial metaverse. Based on the analysis of existing research and the characteristics of industrial scenarios, consistency, authenticity, smoothness, and comfort are identified as the factors that influence the user experience (UX) of industrial MR applications. Specific optimization methods for industrial MR applications are proposed to improve the UX with regard to these four factors. To verify the effectiveness of the proposed methods, a QoE evaluation model of the industrial metaverse based on the fuzzy analytic hierarchy process (FAHP) is established. Moreover, an industrial metaverse prototype for longwall mining that incorporates the proposed methods is developed and its QoE is evaluated. The results show that the proposed optimization methods for industrial MR applications significantly enhance the QoE in the industrial metaverse, and can provide better services for users in industrial systems, thus better serving these systems. 相似文献
78.
Phan Nguyen Ky Phuc 《计算机系统科学与工程》2022,40(1):75-85
Stochastic demand is an important factor that heavily affects production planning. It influences activities such as purchasing, manufacturing, and selling, and quick adaption is required. In production planning, for reasons such as reducing costs and obtaining supplier discounts, many decisions must be made in the initial stage when demand has not been realized. The effects of non-optimal decisions will propagate to later stages, which can lead to losses due to overstocks or out-of-stocks. To find the optimal solutions for the initial and later stage regarding demand realization, this study proposes a stochastic two-stage linear programming model for a multi-supplier, multi-material, and multi-product purchasing and production planning process. The objective function is the expected total cost after two stages, and the results include detailed plans for purchasing and production in each demand scenario. Small-scale problems are solved through a deterministic equivalent transformation technique. To solve the problems in the large scale, an algorithm combining metaheuristic and sample average approximation is suggested. This algorithm can be implemented in parallel to utilize the power of the solver. The algorithm based on the observation that if the remaining quantity of materials and number of units of products at the end of the initial stage are given, then the problems of the first and second stages can be decomposed. 相似文献
79.
80.
Selene Hernández-Rodríguez Author Vitae J. Fco Martínez-Trinidad Author Vitae Author Vitae 《Pattern recognition》2010,43(3):873-5456
The k nearest neighbor (k-NN) classifier has been a widely used nonparametric technique in Pattern Recognition, because of its simplicity and good performance. In order to decide the class of a new prototype, the k-NN classifier performs an exhaustive comparison between the prototype to classify and the prototypes in the training set T. However, when T is large, the exhaustive comparison is expensive. For this reason, many fast k-NN classifiers have been developed, some of them are based on a tree structure, which is created during a preprocessing phase using the prototypes in T. Then, in a search phase, the tree is traversed to find the nearest neighbor. The speed up is obtained, while the exploration of some parts of the tree is avoided using pruning rules which are usually based on the triangle inequality. However, in soft sciences as Medicine, Geology, Sociology, etc., the prototypes are usually described by numerical and categorical attributes (mixed data), and sometimes the comparison function for computing the similarity between prototypes does not satisfy metric properties. Therefore, in this work an approximate fast k most similar neighbor classifier, for mixed data and similarity functions that do not satisfy metric properties, based on a tree structure (Tree k-MSN) is proposed. Some experiments with synthetic and real data are presented. 相似文献