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991.
网络化、协同化是未来特种信息作战飞机的重要作战样式。总结了目前空基网络协同方面存在的主要问题,分析了平台通信组网技术的现状和发展趋势,提出了特种信息作战飞机在战场态势感知、评估、攻击和防护阶段一体化协同的要求。在借鉴美军网络化体系建设的基础上,阐明了推进一体化协同的策略及需要解决的关键问题,为该类装备的一体化协同设计提供指导参考。 相似文献
992.
移动互联网可以满足现代旅游业对个性化、移动性、服务及时性、服务便捷性的需求,催生了面向旅游业的信息服务、导航定位、休闲娱乐、电子商务、社交网络以及虚拟导游等应用,但在发展过程中仍存在行业整合、虚假信息、信息缺失、上网成本、信息安全等问题。 相似文献
993.
一种具有听觉功能的智能视频监控系统 总被引:1,自引:0,他引:1
基于图像的智能视频监控系统由于视角有限,当目标不在摄像头视场范围时,易出现监控盲区,为了解决该难题,利用声源定位的优点,提出一种具有听觉功能的智能视频监控系统。首先采集传声器线性阵列,采用时延估计技术对声源进行定位,然后根据声源位置驱动摄像头,使其转动到声源位置并采集视频信息,最后采用图像检测程序对目标进行实时定位和跟踪,并通过仿真测试验证该系统的可行性,结果表明,该系统具有较好的定位和跟踪精度。 相似文献
994.
995.
当前信息系统的应用逐渐拓展到各个领域,信息工程建设在不断发展的同时所存在的风险不能忽视。在当前大环境下信息安全的涉密信息及其重要,而监理机构作为信息化工程管理的第三方专业机构,针对此部分建设将运用多种方式方法予以管控。本文从涉密信息监理的必要性、涉密工程监理的工作重点等几个方面对此问题进行阐述。 相似文献
996.
文章提出了基于SOA的地籍管理信息系统建设的目标和建设原则.以山东省地籍管理信息系统为例,给出了基于SOA的地籍管理信息系统的应用框架结构设计和实现,并对基于SOA的山东省地籍管理信息系统建设的关键技术和系统特色进行了总结. 相似文献
997.
Analysis of Physiological Responses and Use of Fuzzy Information Granulation–Based Neural Network for Recognition of Three Emotions
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In this study, we investigate the relationship between emotions and the physiological responses, with emotion recognition, using the proposed fuzzy information granulation–based neural network (FIGNN) for boredom, pain, and surprise emotions. For an analysis of the physiological responses, three emotions are induced through emotional stimuli, and the physiological signals are obtained from the evoked emotions. To recognize the emotions, we design an FIGNN recognizer and deal with the feature selection through an analysis of the physiological signals. The proposed method is accomplished in premise, consequence, and aggregation design phases. The premise phase takes information granulation using fuzzy c‐means clustering, the consequence phase adopts a polynomial function, and the aggregation phase resorts to a general fuzzy inference. Experiments show that a suitable methodology and a substantial reduction of the feature space can be accomplished, and that the proposed FIGNN has a high recognition accuracy for the three emotions using physiological signals. 相似文献
998.
This paper proposes an adaptive multimodal in‐vehicle information system for safe driving. The proposed system filters input information based on both the priority assigned to the information and the given driving situation, to effectively manage input information and intelligently provide information to the driver. It then interacts with the driver using an adaptive multimodal interface by considering both the driving workload and the driver's cognitive reaction to the information it provides. It is shown experimentally that the proposed system can promote driver safety and enhance a driver's understanding of the information it provides by filtering the input information. In addition, the system can reduce a driver's workload by selecting an appropriate modality and corresponding level with which to communicate. An analysis of subjective questionnaires regarding the proposed system reveals that more than 85% of the respondents are satisfied with it. The proposed system is expected to provide prioritized information through an easily understood modality. 相似文献
999.
As a memory channel, power‐line communication (PLC) channel can be modeled by the finite states Morkov model. The memory order in an finite states Morkov model is a key parameter, which is not solved in PLC systems yet. In the paper, the mutual information is used as a measure of the dependence between the different symbols, treated as the received scalar network analyzer, or amplitude of the current channel symbol or that of previous symbols. The joint distribution probabilities of the envelopes in PLC systems are computed based on the multi‐path channel model, which is commonly used in PLC. With the first‐order Markovian assumption, we confirm that given the information of the symbol immediately preceding the current one, any other previous symbol is independent of the current one in PLC systems. The field test is also performed to model the received OFDM signals with the help of autoregressive model. The results show that the first‐order autoregressive model is enough to model the fading channel in PLC systems, which means the amount of uncertainty remaining in the current symbol should be negligible, given the information corresponding to the immediately preceding one. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
1000.
Alireza Alizadeh Ghosheh Abed Hodtani 《International Journal of Communication Systems》2015,28(8):1462-1474
In this paper, we consider Rayleigh fading MIMO relay channel with channel state information at the receivers. First, we extend the previously obtained results for the ergodic capacity of uncorrelated and semi‐correlated MIMO channels and derive closed‐form expressions for the capacity bounds of MIMO relay channel. Next, we study this channel from a new point of view, maximizing coverage region for a desired transmission rate, and investigate the optimal relay location in the sense of maximizing coverage region. However, in order to overcome the mathematical complexity in desired transmission rate analysis, because of the randomness of the multiple antenna channel matrices, we evaluate this rate by using an existing exact formula and also by an approximation we find in the high signal‐to‐noise ratio regime. Numerical results show a perfect match between the Monte Carlo simulations and the obtained analytical closed‐form expressions and also confirm the effectiveness of our approach in cooperative vehicular communication for determining optimal relay location at which the coverage region is maximum. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献