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51.
Properly selected transformation methods obtain the most significant characteristics of metal cutting data efficiently and simplify the classification. Wavelet Transformation (WT) and Neural Networks (NN) combination was used to classify the experimental cutting force data of milling operations previously. Preprocessing (PreP) of the approximation coefficients of the WT is proposed just before the classification by using the Adaptive Resonance Theory (ART2) type NNs. Genetic Algorithm (GA) was used to estimate the weights of each coefficient of the PreP. The WT-PreP-NN (ART2) combination worked at lower vigilances by creating only a few meaningful categories without any errors. The WT-NN (ART2) combination could obtain the same error rate only if very high vigilances are used and many categories are allowed.  相似文献   
52.
建筑设备监控系统及节能   总被引:1,自引:0,他引:1  
介绍了建筑设备监控系统(楼宇自动化系统)基本构成和功能,从而指出其节能的内涵。  相似文献   
53.
阐述了离心式冷水机且在线监控系统的工作特点以及对监控的要求,说明了在线监控系统的基本配置,关键技术点和功能模块化的软硬件设计。  相似文献   
54.
凤滩水电厂自动发电控制策略   总被引:1,自引:0,他引:1  
介绍了凤滩水电厂自动发电控制(AGC)策略的实现方法,重点介绍了修正等容量比例有功分配方法及相应措施.程序设计的原则是,机组紧跟目标负荷的情况下,在最佳效率下运行,同时减少机组开/停机次数、有功调节频率和跨越振动区次数,从而减少机组磨损,兼顾运行效率和机组运行安全.  相似文献   
55.
Repeated and prolonged searches of memory can lead to an increase in how much is recalled, but they can also lead to memory errors. These 3 experiments addressed the costs and benefits of repeated and prolonged memory tests for both young and older adults. Participants saw and imagined pictures of objects, some of which were physically or conceptually similar, and then took a series of repeated or prolonged recall tests. Both young and older adults recalled more on later tests than on earlier ones, though the increase was less marked for older adults. In addition, despite recalling less than did young adults, older adults made more similarity-based source misattributions (i.e., claiming an imagined item was seen if it was physically or conceptually similar to a seen item). Similar patterns of fewer benefits and more costs for older adults were seen on both free and forced recall tests and on timed and self-paced tests. Findings are interpreted in terms of age-related differences in binding processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
Barrier options are financial derivative contracts that are activated or deactivated according to the crossing of specified barriers by an underlying asset price. Exact models for pricing barrier options assume continuous monitoring of the underlying dynamics, usually a stock price. Barrier options in traded markets, however, nearly always assume less frequent observation, e.g. daily or weekly. These situations require approximate solutions to the pricing problem. We present a new approach to pricing such discretely monitored barrier options that may be applied in many realistic situations. In particular, we study daily monitored up-and-out call options of the European type with a single underlying stock. The approach is based on numerical approximation of the transition probability density associated with the stochastic differential equation describing the stock price dynamics, and provides accurate results in less than one second whenever a contract expires in a year or less. The flexibility of the method permits more complex underlying dynamics than the Black and Scholes paradigm, and its relative simplicity renders it quite easy to implement.  相似文献   
57.
OPGW应用问题的探讨   总被引:2,自引:1,他引:1  
根据多年的光纤复合架空地线(0PGW)应用经验与实践,从0PGW结构及组成、光纤余长、线路配合、金具配套、0PGW安装等方面,对0PGW应用中的若干问题进行详细的探讨。  相似文献   
58.
改进的BP神经网络在大坝安全监控中的应用   总被引:7,自引:5,他引:2  
针对经典BP神经网络运行中存在的缺陷,提出了改进的BP神经网络,不仅解决了经典BP网络易陷入局部最小的弊端,而且应用的0.618分割选取法能使网络快速找到较优隐含层节点数,初始权值的自相关修正进一步提高了网络的稳定性。实际应用证明,改进的BP神经网络有效提高了网络质量,适合大型网络的构建与训练。  相似文献   
59.
通过南昌市某快速路的设计实例,认识到搞好快速路沿线各交叉口的方案设计是快速路规划设计的关键内容。道路交叉口设计应注重交通功能分析,满足路口交通需求,同时也不能忽视立交的景观要求。  相似文献   
60.
In this paper the application of workflow technology to monitor, control and coordinate business processes and projects is proposed. The conceptual characteristics of processes and projects as well as their management needs in the functions of planning, execution, monitoring and control are compared. The general design of the proposed system is then developed, with an application example. The proposed monitoring and control system provides proactive tracking of the flow of work and information, and of the utilization and commitment of resources. The design supports hierarchical management of the project and/or business process, allowing concerned persons to visualize and to utilize it in different levels of abstraction, as necessary. The application of workflow technology also provides additional benefits in facilitating communication, documentation and re-utilization.  相似文献   
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