The upper bound of the optimal number of clusters in fuzzy clustering

The upper bound of the optimal number of clusters in clustering algorithm is studied in this paper. A new method is proposed to solve this issue. This method shows that the rule cmax≤n~(1/n), which is popular in current papers, is reasonable in some sense. The above conclusion is tested and analyzed by some typical examples in the literature, which demonstrates the validity of the new method.     

涠洲12—1N油田硬脆性泥页岩研究及钻井液技术对策

在涠洲12 1N油田涠二段钻井过程中,硬脆性泥页岩的剥落掉块经常造成钻具阻卡等井下复杂情况。分析了涠二段硬脆性泥页岩的理化特性,研究探讨了硬脆性泥页岩的评价方法和坍塌机理,在此基础上,提出了选用快速强封堵型成膜钻井液是有效抑制硬脆性泥页岩剥落掉块的根本措施。这一研究成果对于在涠洲12 1N油田开发工程中提高钻速、减少井下复杂情况发生具有重要意义。     

大中型笼型异步电动机电容起动的研究

详细描述了大中型笼型异步电动机电容起动的特点，给出了电容初步设计的原则瑟步骤，建立了三相笼型异步电动机电容起动系统的数学模型，并进行仿真计算。理论分析和仿真实例表明，异步电动机采用容起动，可以明显降低起动电流，保持较高的起动转矩，减少起动时间，是一种可供选择的新型起动方法，值得研究与开发。     

一种改进的异步电动机负载性能计算方法

在现有电机电磁计算程序的基础上，通过电机设计理论分析，推导出一种准确计算负载转差率的计算公式，该公式物理概念清晰，没有对精确等铲电路作任何简化。本文提出了一种改进的负载性能算法，对计算某特定输出功率特别有效，不仅具有计算精度，而且简化了计算步骤，大大减小计算工作量，尤其适用于耗时较大的综合设计和优化设计。     

Mining Adaptive Ratio Rules from Distributed Data Sources

Different from traditional association-rule mining, a new paradigm called Ratio Rule (RR) was proposed recently. Ratio rules are aimed at capturing the quantitative association knowledge, We extend this framework to mining ratio rules from distributed and dynamic data sources. This is a novel and challenging problem. The traditional techniques used for ratio rule mining is an eigen-system analysis which can often fall victim to noise. This has limited the application of ratio rule mining greatly. The distributed data sources impose additional constraints for the mining procedure to be robust in the presence of noise, because it is difficult to clean all the data sources in real time in real-world tasks. In addition, the traditional batch methods for ratio rule mining cannot cope with dynamic data. In this paper, we propose an integrated method to mining ratio rules from distributed and changing data sources, by first mining the ratio rules from each data source separately through a novel robust and adaptive one-pass algorithm (which is called Robust and Adaptive Ratio Rule (RARR)), and then integrating the rules of each data source in a simple probabilistic model. In this way, we can acquire the global rules from all the local information sources adaptively. We show that the RARR technique can converge to a fixed point and is robust as well. Moreover, the integration of rules is efficient and effective. Both theoretical analysis and experiments illustrate that the performance of RARR and the proposed information integration procedure is satisfactory for the purpose of discovering latent associations in distributed dynamic data source.     

智能马达控制器(SMC)的应用

SMC智能马达控制器是一种新型三相异步电动机的起动运行控制器.本文介绍了SMC的主要功能和使用方法;通过大量实验波形和数据,对起动和节能运行状态进行了分析研究.     

聚氨酯硬泡箱式自由发泡工艺浅谈

制备了聚醚组合料,并采用自由发泡工艺制备大体积硬质聚氨酯泡沫塑料,讨论了控制泡沫烧芯的有关因素。     

航空发动机鼓筒连续扫描模态测试方法研究

针对航空发动机鼓筒等薄壁圆柱壳型结构,以薄壁圆柱壳为例,基于LabVIEW测试平台、利用非接触式电磁激振器搭建了模态参数测试实验台,并对实验台校准时的各个自由度偏差进行误差分析,给出灵敏度指数指导实验台校准。基于扫频信号包络线法辨识圆柱壳的固有频率,避免能量泄漏,提高辨识精度;基于共振响应辨识模态振型,利用激光旋转扫描测试,提高模态振型测试效率,并研究不同转速下的测试精度。将测试结果与LMS模态分析软件所测结果进行对比,结果表明,利用文中的测试方法得到的模态参数更为准确,具有一定的工程应用价值。     

智能变电站简易母线保护

分析了低压母线的保护配置现状,提出了一种简易母线保护新方案。该方案根据低压母线主接线特点抽象出母线单元模块,各母线单元模块根据本母线进线、分段开关的过流情况及其他母线单元模块的开关过流情况,结合出线保护的闭锁信号,实现小电源、进线和分段的选择性跳闸,达到快速切除母线故障的目的。     

多功能电机保护控制一体化装置的研究

提出了交流电动机保护-控制一体化的概念,既能对电动机进行可靠的保护,又能对电动机进行节能控制和软起动控制。文中给出了电动机保护和有关控制的基本原理与设计思想,并对该装置的硬件结构与软件设计中的关键部分进行了讨论。