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1.
This editorial paper provides an overview of new advances on hardware security challenges and promising solutions for real world applications. It first presents the increasing hardware vulnerabilities with the emergence of diverse computing platforms. Then, it details the technical challenges, research opportunities, and potential solutions to cyber-attacks on -physical- devices.  相似文献   
2.
针对软件定义网络中,控制器无法保证下发的网络策略能够在转发设备上得到正确执行的安全问题,提出一种新的转发路径监控安全方案。首先以控制器的全局视图能力为基础,设计了基于OpenFlow协议的路径凭据交互处理机制;然后采用哈希链和消息验证码作为生成和处理转发路径凭据信息的关键技术;最后在此基础上,对Ryu控制器和Open vSwitch开源交换机进行深度优化,添加相应处理流程,建立轻量级的路径安全机制。测试结果表明,该机制能够有效保证数据转发路径安全,吞吐量消耗比SDN数据层可信转发方案(SDNsec)降低20%以上,更适用于路径复杂的网络环境,但时延和CPU使用率的浮动超过15%,有待进一步优化。  相似文献   
3.
The relationship between location and land use patterns is one of the classic theoretical issues in urban studies. Classic models based on the monocentricity hypothesis have limitations in the interpretation of modern urban structure. China has experienced institutional transformation in recent decades, and the interaction of national government policy, market forces and the natural environment has influenced urban planning in Chinese metropolises, resulting in urban structures with special characteristics. This paper examines the distribution of location and land use intensity, and tested the Alonso model by the relationship between them in five Chinese metropolises using Point of Interest data, space syntax methodology, the grid weighted statistical method and the Geographically Weighted Regression (GWR) model. Universal patterns about the scaling relation between intensity of land use types and the centrality of location are revealed. The elasticity of land use types to location, from high to low sensitivity, is commercial, residential then industrial land in most of the five metropolises studied. The sensitivity sequence of land use studied suggests that the hypothetical model based on the classical Alonso model can explain the spatial structure of modern metropolises in China to some extent, especially for the commercial land. But the order of sensitivity of residential land and industrial land to location does not conform to the model. The spatial heterogeneity in land use intensity and centrality were explored and the factors embedded were discussed. It can be found that the relation between centrality and land use intensity conforms to power law. In most of the metropolises studied, when the scaling relation between land use intensity and centrality is super linear, the sequence of the frequency value from high to low are commercial, residential and industrial land; when the scaling relation is sublinear, the sequence of the frequency value is industrial, residential and commercial land.  相似文献   
4.
静电复印机是常用的办公设备,复印时要将不同规格的复印纸装入纸盒,经常需要操作者对纸盒进行调整。从使用者的角度讲,要用最小的力气、最简便的方法来完成对机器的操纵。这就需要考虑进行人性化设计。纸盒调整主要有自动监测纸盒尺寸的功能和纸盒内侧挡板(导纸板)的调整。对比不同品牌和不同机型复印机的纸盒设计,可看出人性化设计对方便操作者使用的重要性,也为购买机器时提供了借鉴。  相似文献   
5.
随着通信和信息技术的跨越式发展,传统呼叫中心已经难以满足企业快速增长的需求,同时以客户为中心和以服务为导向的经营理念对新一代联络中心提出了更高的要求。在联络中心技术快速革新的背景下,文中以软交换、NGN和分布式技术为基础,深入研究了基于融合技术的新一代联络中心的系统架构和软交换平台的逻辑关系,构建了支持全媒体业务和标准化SIP的统一通信平台。文章以联络中心中实时和非实时业务为例,分析设计了适合联络中心典型的话务和多媒体业务的信令流程,提出了适应新一代联络中心的业务部署方式,利用模糊综合评价方法对不同部署方式的特点进行对比评估,为新一代联络中心在大型企业中推广和应用提供重要的理论和实践依据。  相似文献   
6.
李运 《自动化应用》2012,(12):56-57,61
分析PLC接地的特殊性,阐述PLC接地的主要方法,介绍几种接地防干扰措施。  相似文献   
7.
Perceptual scenes and scene swing surveys are the ideas for reminding local and wooded area park executives and scene placement. The maximum precise analysis of panorama visualization, forest park landscapes, planning of essential scenic spots, and visualization and safety of Geographic Information Systems (GIS) cost tools is primarily based on management and historical data. Visual impacts and cultural, historical past adjustments to are expecting visual and natural landscapes. By deciding on points from a panorama attitude, intervention calls for vital signs and symptoms of safety. Among them, studies are being carried out in many towns around the arena. Geographic Information System (GIS) depends simply on noticeable assessment and is remembered for the social legacy plan. The Gate Array (FPGA) and Geographic Information System (GIS) are analyzed based on the panorama in every place within the painting's framework. In these activities, landscape planning is proposed thru the development of scientific Piedmont. Turin is conducting a few research. From a global attitude, the version suggests that these packages reduce the capability use of the era.  相似文献   
8.
Dance is the expression of artists' favourite art forms such as express emotions, their body language, and the combination of dance art and stage effects in dance performance. In almost all genres of the art form, the effectiveness of the dance performance is largely due to the quality of the individual dancer's and group dance performance. Performing arts, particularly dance, it is one of the most important of intangible cultural heritage. However, due to the preservation, documentation, analysis, and visualization understanding of dance mode, it is difficult because of technical difficulties relations. The Proposed Machine Learning Support Decision Vector Machine (SDVM) algorithm and Field Programmable Gate Array (FPGA) is a dance expert watching dance due to the recognition task, the task knowledge of professional forecasters, gestures, and facial expressions and face-to-face conditions led to better synchronization of timing. In the proposed Machine learning SDVM algorithm, the results show that positive and dancers in the audience increased negative emotions; acceleration rate and body movement also increased. SDVM is classified as dancer performance based on the artist's facial expressions, stage performance, emotions. The simulation results show good results compared to other methods.  相似文献   
9.
基于半监督学习和支持向量机的煤与瓦斯突出预测研究   总被引:1,自引:1,他引:0  
针对支持向量机要求输入向量为已标记样本,而实际应用中已标记样本很难获取的问题,提出将半监督学习和支持向量机结合的煤与瓦斯突出预测方法;介绍了采用SVM预测煤与瓦斯突出的流程及其输入向量的选择;对半监督学习中的协同训练算法进行了改进:在同一属性集上训练2个不同分类器SVM和KNN,将2个分类器标记一致的样本加入训练集,从而充分利用未标记样本不断补充信息,更新训练集标记样本,达到强化训练集的目的。测试结果表明,改进后的算法比单独的支持向量机预测方法准确率更高。  相似文献   
10.
赵一博  史运涛  董哲  李晓硕 《控制工程》2012,19(3):511-514,530
根据海军某基地实际附属设备及环境参数的监控要求,设计并实现了自动化设备综合监控系统。该系统使用西门子WinCC及S7-300/200 PLC开发完成,实现了WinCC C/S,B/S架构及S7-300/200PLC的Profibus-DP主从站结构,构建了集环境温湿度监控、设备监控、变电站监控和风水监控一体的综合监控系统,解决了复杂的第三方通讯、控制逻辑问题,实现了设备状态信息现场采集、中心管理、远程控制的功能。实际的运行效果证明,该系统设计合理,具有良好的可靠性和实用性。  相似文献   
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