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排序方式: 共有204条查询结果,搜索用时 262 毫秒
41.
张云鹏 《电子工业专用设备》2013,(11):42-49
阐述一种基于PMAC(Programmable Multi-AxisController)控制卡的步进电机构成的伺服系统PID(ProportionIntegral Derivative)算法。详细的介绍了系统的组成和工作原理,以及PID参数的调节原理和调节方法。我们借助PEWINTUNING软件,通过分析系统响应曲线,观察系统的稳态特性和动态特性。 相似文献
42.
阐述了不完全微分PID算法的原理,以及两种微分算法的数学推导算式与控制输出作用比较,并对其进行了相应的MATLAB仿真实验,取得了较好的控制效果。 相似文献
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44.
为简化旅客列车开行方案优化编制问题,采用聚类法对铁路客运节点进行类别划分。选取2014年日均旅客发送量排名前100位客运节点的相关属性数据为实例,以铁路客运节点的类别划分依据作为属性变量,首先运用分层聚类中的凝聚法对属性变量进行聚类,然后根据简化的客运节点变量指标,运用近邻传播算法对客运节点样本其进行聚类,并引用CH、KL、IGP等三种聚类有效性指标对聚类结果加以分析。研究结果表明,将100个客运节点分为5个类别时,具有最好的聚类效果,可为旅客列车开行方案的设计奠定基础。 相似文献
45.
针对减小比例控制器配比精度对三组元推进剂能效影响的问题,基于三转子流量计工作原理设计了三转子式比例控制器,试验研究了定流量和变流量工况下工程样机的流量比例控制性能。结果表明:三转子式比例控制器的结构简单、易加工、运动平稳、阻尼小;定流量工况下比例控制器的配比比例稳定且精度较高,而且各流量工况点间的配比比例也一致;变流量工况下比例控制器的配比比例存在波动,但其波动幅值随着流量的增大而减小;比例控制器燃烧剂路造成的压力损失最大,冷却剂路造成的压力损失最小。研究成果为研制新型、高配比精度的比例控制器提供了新方案。 相似文献
46.
Summary A new two stage partial randomized response procedure is proposed. The proposed strategy is compared with Mangat and Singh's
(1990) strategy. The proposed strategy, as well as its special case in single stage, are also compared with the usual Warner's
(1965) strategy. Better efficiency conditions are obtained in each comparison. 相似文献
47.
A New Strategy for Quantitative Proportions in Complex Systems of Blended Oils by Triacyglycerols and Chemometrics Tools 下载免费PDF全文
Hong?Yang Pei-Jin?Tong Yuan-Rong?JiangEmail author Wen-Ming?Cao Xi-Chang?WangEmail author Ting-Ting?Wei Tong?Li Cheng?Zhong Yi-Ming?Zhang Chuan?Zhou Zhuo-Ping?Ding Yu-Quan?Zhang 《Journal of the American Oil Chemists' Society》2017,94(5):631-642
Many oils sold in China and India are a blend of various oils to improve performance, stability, and nutritional characteristics, which are required in their respective markets. Quantitative analysis of the proportions of constitutive components is fundamental to the conformity and adulteration checking of edible blended oil products. A multi linear regression model with constrained linear least squares and exhaustion calculation was applied in this study. The source of the varieties in the model is a database (614 pure oils) of triacylglycerols (TAGs) collected by GC–FID and HPLC–RID. There were 20 groups of binary and ternary blended oils consisting of two or three oils out of five kinds, namely soybean, corn, peanut, rapeseed, and sunflower, which were analyzed and processed separately. Results showed that the method was able to predict the proportions of constitutive components in the edible blended oils, given that relative errors required less than 20%, the accuracy was 98.2% for the binary system if the proportion of each oil in blended oils was more than 20%, while the accuracy was 84.7% for the ternary system if the proportion of each oil in blended oils was more than 10%. The quantitative method is based on a simple analysis to determine the TAGs composition and thus it is useful for quick segregation and quality control of blended oils in routine analysis. 相似文献
48.
Chloé FriguetDavid Causeur 《Computational statistics & data analysis》2011,55(9):2665-2676
In multiple testing, a challenging issue is to provide an accurate estimation of the proportion π0 of true null hypotheses among the whole set of tests. Besides a biological interpretation, this parameter is involved in the control of error rates such as the False Discovery Rate. Improving its estimation can result in more powerful/less conservative methods of differential analysis. Various methods for π0 estimation have been previously developed. Most of them rely on the assumption of independent p-values distributed according to a two-component mixture model, with a uniform distribution for null p-values. In a general factor analytic framework, the impact of dependence on the properties of the estimation procedures is first investigated and exact expressions of bias and variance are provided in case of dependent data. A more accurate factor-adjusted estimator of π0 is finally presented, which shows large improvements with respect to the standard procedures. 相似文献
49.
一种新型的快速无超调预测控制器及其应用 总被引:2,自引:2,他引:2
该文采用一种比例积分型结构,建立了一种无超调预测控制器,通过钻杆热处理的退火过程控制的仿真研究,验证了该控制器的有效性。 相似文献
50.
冯立蛟 《可编程控制器与工厂自动化(PLC FA)》2014,(2):37-40
本文主要介绍永宏PLO在充绒机中的应用,通过喷绒时间控制,喷绒比例控制,实现绒的小误差称量。 相似文献