基于模糊评价的六西格玛项目选择研究

由于六西格玛项目选择是成功实施六西格玛项目管理的最重要环节之一,针对六西格玛项目选择的特点,结合模糊评价方法,建立了六西格玛项目选择的模糊评价流程,在分析六西格玛项目评价指标体系的基础上,提出了六西格玛项目选择的模糊评价方法。最后通过重庆某大型企业的实例应用,验证了该方法的合理有效性,提高了企业选择六西格玛项目的精确性,使企业实施最优化项目而获得最大利益和成功,也拓展了六西格玛项目管理应用研究的内容。     

装备维修辅助过程质量改进中的参数确定与测量分析

针对装备维修存在消耗大、效益小、污染重、环保轻的问题,基于"大质量观",文章运用六西格玛管理(Six Sigma Management,SSM)研究装备维修辅助过程的质量改进.介绍了SSM的基本思想,界定了装备维修辅助过程的概念和内涵;运用质量功能展开将装备维修辅助过程质量要求转化成可供测量的过程质量参数,并从重复性和再现性两个方面进行了测量系统分析,验证了测量系统的精确性.     

应用六西格玛管理降低爆破根块率

本文针对白云鄂博铁矿爆破根块率偏高问题,运用了六西格玛管理方法予以改善及控制。通过利用六西格玛管理方法分别从定义、测量、分析、改进、控制五个方面进行开展并应用。应用表明其爆破质量得到有效地改善,爆破根块率降低到16个/万t,并产生经济效益约15万元,为确保矿山有序生产提供了基础保证。     

基于多软件协同仿真的六自由度平台虚拟试验系统

提出了一种串联六自由度运动平台,根据该平台特点,在ADAMS动力学分析软件中搭建机械子系统模型,在AMESim仿真软件中搭建液压子系统及电机+滚珠丝杠传动模型,在Simulink中搭建末端控制对象期望运动位姿生成及解耦控制算法模型。通过分析各仿真软件间数据传输接口特性,建立以MATLAB软件为载体的动态数据共享通道,将ADAMS、AMESim模型分别以子模型及S函数形式导入至Simulink。从而建立基于Simulink为主仿真软件的机、电、液一体化的六自由度运动平台虚拟试验系统,实现平台的全面仿真分析,为平台实体设计与优化、控制策略选择等奠定基础。采用的基于MATLAB为主仿真软件的ADAMS、AMESim、Simulink联合虚拟试验系统创建方法对于复杂机、电、液一体化系统的仿真分析具有普遍的适用性。     

MASH结构ADC中的自适应校正系统设计

随着大规模集成电路的快速发展,Delta-Sigma（∑-△）模数转换技术因为它的良好性能和易集成的优势,越来越受到广泛的关注和应用。本文针对实际电路相对于理想设计的性能下降来分析其原因。同时针对主要来自模拟电路的诸如实际电容的不精确匹配、放大器的有限增益等因素,通过MATLAB模型来详细分析这些模拟电路误差会对于电路性能产生的影响。本文同时提出了一种自适应校正系统,通过将LMS自适应算法应用于ADC电路,来获得对模拟电路误差的校正。并通过MATLAB分析获得理想状态、无校正系统和校正系统的性能比较来体现校正系统的实际应用价值。     

Design,Fabrication and Preliminary Study of a Mini Power Source with a Planar Six‐cell PEM Unitised Regenerative Fuel Cell Stack

A novel micro planar fuel cell power supplier, in which a six‐cell PEM unitised regenerative fuel cell (URFC) stack is used as the power generator, was designed and fabricated. Six membrane electrode assemblies were prepared and integrated on one piece of membrane by spraying catalyst slurry on both sides of the membrane. Each cell was made by sandwiching a membrane electrode assembly (MEA) between two graphite monopolar plates and six cell units were mechanically fixed in two organic glass endplates. When the stack was operated in an electrolysis mode, hydrogen was generated from the splitting of water and stored using a hydrogen storage alloy; conversely, when the stack was operated in fuel cell mode, hydrogen was supplied by the hydrogen storage alloy and oxygen was supplied from air by self‐breathing of the cathode. At room temperature and standard atmospheric pressure, the open‐circuit voltage (OCV) of the system reached 4.9 V, the system could be discharged at a constant current density of 20 mA cm^–2 for about 40 min, and the work voltage was ∼2.9 V. The system showed good stability for 10 charge–discharge cycles.     

微加速度计中Sigma Delta调制与 脉冲编码调制的对比分析

对Sigma Delta调制与脉冲编码调制进行对比,研究了Sigma Delta调制与脉冲编码调制的优缺点。建立了微加速度计中两位输出的Sigma Delta调制和两位输出的脉冲编码调制的仿真系统。然后,对比使用这两种调制方式的微加速度计的加速度信号,并分析在两种不同调制方式下的输出信号波形的差别。最后,利用周期图法得到了两种调制信号的功率谱密度图,发现在低频段脉冲编码调制信号的量化噪声比Sigma Delta调制信号大很多;而在高频段,两种调制方式信号的量化噪声一样严重。仿真结果表明,尽管Sigma Delta调制系统比脉冲编码调制系统更加复杂,但是Sigma Delta调制得到的信噪比要比脉冲编码调制得到的信噪比高出20 dB。     

Six sigma-based approach to optimize deep drawing operation variables

The six sigma approach has been increasingly adopted worldwide in the manufacturing sector in order to enhance the productivity and quality performance and to make the process robust to quality variations. This paper deals with one such application of six sigma methodology to improve the yield of deep drawing operations. The deep drawing operation has found extensive application in producing automotive components and many household items. The main issue of concern of the deep drawn products involves different critical process parameters and governing responses, which influences the yield of the operation. The effects of these parameters are analysed by the DMAIC (Define, Measurement, Analyse, Improve, Control)-based six sigma approach. A multiple response optimization model is formulated using the fuzzy-rule-based system. The functional relationship between the process variables and the responses is established, and thereafter their optimum setting is explored with the aid of response surface methodology (RSM). Rigorous experimentations have been carried out, and it is observed that the process capability of processes is enhanced significantly, after the successful deployment of the six sigma methodology.     

Two-phase selection framework that considers production costs of suppliers and quality requirements of buyers

Buyers are faced with selecting the optimal supplier, while suppliers are left to consider production costs. In this study, we developed a two-phase selection framework that allows buyers to evaluate the performance of suppliers while taking production costs into account for value maximisation. This scheme is a win-win solution capable of promoting long-term relationships between buyers and suppliers. Under the assumption of normality, the first phase involves constructing a new Six Sigma quality capability analysis chart (SSQCAC) which takes production costs into account. The objective is to evaluate all potential suppliers using the 100?×?(1–α)% upper confidence limit (UCL) of an integrated Six Sigma quality index (SSQI) Q_PIh when dealing with products with smaller-the-better (STB), larger-the-better (LTB), or nominal-the-best (NTB) quality characteristics. According to interval estimation theory, this method can have a significant impact on the consumption of resources; i.e. the production costs of the supplier can be decreased by reducing the production quality to below that required by the buyer. The proposed method also filters out unsuitable suppliers in order to simplify the decision problem and reduce computational demands and operational risks/costs without compromising the quality of the final product. In the second phase, a detailed analysis is conducted using Euclidean distance measure to select the optimal supplier from among the remaining candidates. We conducted a real-world case study to evaluate the efficacy of the proposed method. We also conducted comparisons with existing methods to demonstrate the advantages of the proposed method and its managerial implications. Suggestions for future study are also provided.     

强势统一还是循序渐进?——山东能源集团文化融合经验谈

文化融合模式没有定式,关键是能否达到同向、同道、同行,实现"形神合一",发挥重组企业"1+1>2"的效果。山东能源集团根据自身的特点采取了传承包容与创新超越并重,强势统一与循序渐进同步,快节奏推进、分阶段融合的策略,开创了大型重组国企文化融合的山东模式。