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排序方式: 共有1344条查询结果,搜索用时 31 毫秒
71.
执行机构含死区环节的自适应补偿控制 总被引:6,自引:1,他引:6
火电厂炉膛负压控制系统中有时含死区类的强非线性环节,死区使该控制回路产生振荡,仅用常规PID控制器无法克服这一现象。为此,该文提出了一种用自适应死区逆对控制回路进行补偿的方法。该方法用描述死区特性的参数构造死区逆来补偿控制器输出;同时又由于死区是未知和时变的,所以用一种鲁棒自适应更新律对死区参数进行在线更新,从而达到用死区逆完全抵消死区影响的目的。仿真试验结果表明,该文的方法几乎能让系统恢复到线性状况,并且死区参数收敛,证明了方法的有效性。 相似文献
72.
我国水泥工业的可持续发展应该朝着“四零一负”的目标发展,即水泥企业对其周围生态环境完全达到零污染;水泥熟料生产企业对外界电能的零消耗;水泥企业对废料、废渣、废水的零排放;熟料生产对天然矿物燃料(煤、油、天然气)的零消耗;水泥企业对全社会废料、废渣的负增长作出应有的贡献。科学技术的进步和实践证明,这一目标离我们不是太远。 相似文献
73.
Bilal Alataş Erhan Akin 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2006,10(3):230-237
In this paper, a genetic algorithm (GA) is proposed as a search strategy for not only positive but also negative quantitative
association rule (AR) mining within databases. Contrary to the methods used as usual, ARs are directly mined without generating
frequent itemsets. The proposed GA performs a database-independent approach that does not rely upon the minimum support and
the minimum confidence thresholds that are hard to determine for each database. Instead of randomly generated initial population,
uniform population that forces the initial population to be not far away from the solutions and distributes it in the feasible
region uniformly is used. An adaptive mutation probability, a new operator called uniform operator that ensures the genetic
diversity, and an efficient adjusted fitness function are used for mining all interesting ARs from the last population in
only single run of GA. The efficiency of the proposed GA is validated upon synthetic and real databases. 相似文献
74.
Tien Van DoAuthor Vitae 《Performance Evaluation》2011,68(4):330-337
In this paper, we consider a queueing model extension for a manufacturing cell composed of a machining center and several parallel downstream production stations under a rotation rule. A queueing model is extended with the arrival processes of negative customers to capture failures of production stations, reorganization of works and disasters in the manufacturing cell. We present an exact solution for the steady-state probabilities of the proposed queueing model. The solution does not require the approximation of the infinite sum. In addition, it provides an alternative way to compute the rate matrix for the matrix-geometric method as well. 相似文献
75.
下喷式焦炉在使用焦炉煤气加热时,交换后经常发生爆呜(俗称放炮)现象,它对于焦炉危害巨大,文章对爆呜现象发生的机理以及它的危害进行了分析,介绍了一些减少或消除爆呜现象的措施,特别对如何在操作维护中做好针对性的工作做了较详细的介绍。 相似文献
76.
Lanlin Yu 《International journal of systems science》2017,48(7):1515-1521
This paper is concerned with the H∞ model reduction for negative imaginary (NI) systems. For a given linear time-invariant system that is stable and NI, our goal is to find a stable reduced-order NI system satisfying a pre-specified H∞ approximation error bound. Sufficient conditions in terms of matrix inequalities are derived for the existence and construction of an H∞ reduced-order NI system. Iterative algorithms are provided to solve the matrix inequalities and to minimise the H∞ approximation error. Finally, a numerical example is used to demonstrate the effectiveness of the proposed model reduction method. 相似文献
77.
As the use of the computer is popularized, the damage from computer viruses and hacking by malicious users is increasing rapidly.
To block the hacking that is an intrusion into a person's computer, and the viruses that destroy data, a study into an intrusion
detection and virus detection system based on the biological immune system is in progress. In this article, we describe a
model of positive and negative selection for self-recognition, which has a similar function to the cytotoxic T cells that
play an important role in the biological immune system. We propose a self/nonself discrimination algorithm for a computer
system, which will the important when we detect data infected by a computer virus, of data modified by an intrusion from outside.
We also show the validity and effectiveness of the proposed self-recognition algorithm by a computer simulation of some infected
data obtained from cell changes and string changes in the self-file.
This work was presented, in part, at the Seventh International Symposium on Artificial Life and Robotics, Oita, Japan, January
16–18, 2002 相似文献
78.
在粒子辐射探测器偏压电源中,发现输出电压有低频纹波存在。在实验中,发现利用纹波相位变换技术能有效消除输出电压的低频纹波。以理论分析和PSpice仿真分析为基础对取样电路进行设计。按照该设计实现的某型号卫星高能粒子探测器的高压电源,输出电压稳定、纹波系数小,达到设计目的。试验证明这种电路设计,简单、高效,可为相关电路设计提供参考。 相似文献
79.
As we known, Q charts are SPC charts for approximate normal distribution. This paper proposes new kinds of Q charts for negative binomial random variable. First, define two transformations of approximate standard normal distribution for a negative binomial parameter p which it is known or unknown. Then, Q charts are constructed by transformed data, these Q charts are useful for monitoring process in real time from the beginning of sampling, especially, for p unknown in advance. In order to compare the goodness of the Q charts with conventional Shewhart charts with 3-sigma limits, an example is given. The results have shown that these Q charts are more efficient than classical Shewhart charts. Finally, some review are given. 相似文献
80.
一种基于人工免疫理论的入侵检测模型 总被引:1,自引:0,他引:1
谢建全 《数字社区&智能家居》2006,(11)
基于智能技术的异常检测正成为IDS研究的一个重要方向,其研究目标主要是提高检测系统的准确性、实时性、高效性以及自适应性,借鉴生物免疫系统的计算机免疫系统将成为解决入侵检测问题的有效手段。本文分析了生物免疫系统的原理,结合生物免疫理论,提出一种基于检测代理的分布式网络入侵检测免疫模型。 相似文献