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排序方式: 共有2147条查询结果,搜索用时 15 毫秒
81.
探讨和分析了时钟同步网指标和移动基站指标,结合本地网时间指标的分析,尝试给出了IP环境下同步网模型和指标分配。讨论的重点是时钟同步网,并在一定程度上论述了时间同步网。 相似文献
82.
概述了193nm浸液式光刻技术发展现状及技术路线,结合国际半导体技术发展指南(ITRS)和各公司在SPIE微光刻研讨会上宣布的最新研究成果,探讨了193nm浸液式光刻技术的发展趋势。 相似文献
83.
针对目前基站站址资源获取评估标准的不一现状,基于AHP建立了一套基站站址资源储备的评估指标体系,并详细地阐述了具体的评估方式和方法。 相似文献
84.
童志义 《电子工业专用设备》2007,36(4):8-16
概述了用于45nm节点的各种光刻技术发展现状及技术路线,结合国际半导体技术发展指南(ITRS)和各公司最新宣布的研究成果,探讨了各种光刻技术用于32nm节点的可能性。 相似文献
85.
Because of rapid development in network technology,Internet usage has become widespread.It allows users with sensing devices to obtain medical data for healthcare,such as physiological signals,voice,and video streams from telemedicine systems,and to send the healthcare data to back-end database systems,creating a ubiquitous healthcare environment.However,this environment requires a widespread and suitable network.IPv6(Internet protocol version 6) is the next-generation Internet protocol that will be the protocol of future networks;it improves many shortcomings of IPv4.In this paper,we propose an IPv6/IPv4 U-home-care test system and analyze the network’s parameters though a series of tests by adjusting network parameters to find the optimal design for applications in the IPv6/IPv4 U-home-care service so as to assure good performance and high quality. 相似文献
86.
Abstract--Near field communications (NFC) is a newly thrived technology in recent years. This technology has been installed on many kinds of mobile phone systems, especially the Android. However, there is no unified and complete framework to access NFC so far. The current software stack of NFC merely implements data obtaining features, ignoring the post-processing of data and lacking a certain security mechanism for NFC, which results in inefficiency and inconvenience for software development and maintenance. Above all, security problems could be caused due to the absence of the security mechanism. To propose a solution, this paper presents a brand-new framework for NFC utilization by analyzing and constructing a service model. Thus, the proposed framework encapsulates the current NFC stack on Android, formulating a three-layer structure after implementing the encapsulation and parsing of NFC records, which ultimately enables an XML document to describe the configuration of NFC and its related service flow. Simultaneously, a context-awareness model is proposed and built in this paper to equip the framework with the capability of adapting to different'physical environment. 相似文献
87.
Sreenivas Yelneedi S. Lakshminarayanan G.P. Rangaiah 《Journal of Process Control》2009,19(9):1458-1469
The anesthetic state is a dynamic combination of hypnosis, analgesia and neuromuscular blockade that is maintained by infusing a cocktail of drugs. This work focuses on controlling the hypnosis during a surgical procedure by automatic regulation of isoflurane and employs Bispectral Index (BIS) as the primary controlled variable. A seventh-order nonlinear pharmacokinetic–pharmacodynamic representation has been used for the hypnosis dynamics of patients. This study uses a model predictive control structure for the regulation of BIS. Performance of this controller has been tested for a range of patients and compared with two previously employed control strategies (cascade internal model controller and cascade controller with modeling error compensation). Performance of the three controllers has also been studied for a step change in BIS, measured disturbances and noise in the measured variables. Numerical simulations show that the model predictive controller performed better than the other two controllers. 相似文献
88.
科技型中小企业是指以科技人员为主创办的、以创新为发展动力的、主要从事高新技术产品的研制、开发、生产和服务业务的中小规模的企业.指出了构造科技型中小企业创新能力评估指标体系的依据和原则,指标的权重确定方法采用人工神经网络技术赋予,设计了一套适合于评估科技型中小企业创新能力的指标体系,并给出了数据分析的方法和步骤,采用密切值法计算其相对排序. 相似文献
89.
M. F. Azeem M. Hanmandlu N. Ahmad 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2005,9(3):211-221
This paper underlines a way to evolve a generalized fuzzy model (GFM), using the interpolation of CRI and TS models in their consequent parts of fuzzy rules. The GFM possesses the index of fuzziness of CRI model and the local model of the TS model. The parameters of the GFM are estimated by a two-step process. The consequent part of fuzzy rules is reformulated to suit the LSE framework for estimating the associated parameters. By assuming Generalized Gaussian membership function for the premise parts, Gradient descent technique is used to update its parameters. The performance of two classes of GFM has been tested on two systems and it is shown that class II GFM is the best out of all the fuzzy models tested. 相似文献
90.
刘健 《青岛大学学报(工程技术版)》1993,(4)
对利用楔形分束器和楔形反射镜消除透射光及反射光中的鬼线或幻影进行了理论分析,给出了入射角与相应楔角的对应关系公式;并就实例进行了分析讨论。 相似文献