Disentangling causal relationships of a manufacturing process using genetic algorithms and six-sigma techniques

The manufacturing of hard disk drive storage is a highly competitive industry due to ever changing technology and the introduction of solid-state storage. Therefore manufacturers have introduced business improvement techniques to help leverage manufacturing advantages over competitors. This paper aims to investigate the integration of business improvement methodologies with intelligent techniques for the improvement of manufacturing efficiency. The authors use a case study based on the disentangling of causal relationships during the manufacturing of hard disk drive components. This paper reports on the application of intelligent system techniques to aid implementation of business improvement methodologies within this manufacturing environment. The results reported highlight that significant gains may be made when utilizing such a hybrid approach. The approach is validated by determining the secondary effects that degraded a previously implemented six-sigma project and also by identifying areas of investigation that enabled engineers to improve process yield.     

A wideband time‐based continuous‐time sigma‐delta modulator with 2nd order noise‐coupling based on passive elements

Embedding the time encoding approach inside the loop of the sigma‐delta modulators has been shown as a promising alternative to overcome the resolution problems of analog‐to‐digital converters in low‐voltage complementary metal‐oxide semiconductor (CMOS) circuits. In this paper, a wideband noise‐transfer‐function (NTF)‐enhanced time‐based continuous‐time sigma‐delta modulator (TCSDM) with a second‐order noise‐coupling is presented. The proposed structure benefits from the combination of an asynchronous pulse width modulator as the voltage‐to‐time converter and a time‐to‐digital converter as the sampler to realize the time quantization. By using a novel implementation of the analog‐based noise‐coupling technique, the modulator's noise‐shaping order is improved by two. The concept is elaborated for an NTF‐enhanced second‐order TCSDM, and the comparative analytical calculations and behavioral simulation results are presented to verify the performance of the proposed structure. To further confirm the effectiveness of the presented structure, the circuit‐level implementation of the modulator is provided in Taiwan Semiconductor Manufacturing Company (TSMC) 90 nm CMOS technology. The simulation results show that the proposed modulator achieves a dynamic range of 84 dB over 30 MHz bandwidth while consuming less than 25 mW power from a single 1 V power supply. With the proposed time‐based noise‐coupling structure, both the order and bandwidth requirements of the loop filter are relaxed, and as a result, the analog complexity of the modulator is significantly reduced. Copyright © 2015 John Wiley & Sons, Ltd.     

一款使用低功耗多级运放实现的12位，20兆带宽，18毫瓦的连续时间型过采样调制器

本文在130纳米CMOS工艺下实现了一种具有20兆赫兹带宽,四阶连续时间型过采样调制器。调制器由有源积分环路滤波器、4位内部量化器和3个电流舵型反馈数模转换器构成。本文提出了一种三级运算放大器,它可以在获得高带内增益和高带宽的同时消耗较小的功耗。为了减小时钟抖动对连续时间型过采样调制器的影响,内部反馈数模转化器采用了不自归零的反馈波形。同时采用特殊的版图技术保证数模转换器的线性度,同时避免使用动态器件匹配技术引入的额外环路延时。芯片工作在1. 2 V 电源电压和480 M Hz 时钟频率, 在20 MHz 的信号带宽内, 调制器的动态范围为66 dB, 峰值SNR为64.6 dB, 功耗为18 mW。     

运用六西格玛方法提高装载机整机装配防护品质

阐述了通过运用六西格玛方法,提高装载机整机装配过程防护品质的实施方法。项目组在项目的实施过程中,运用了六西格玛方法和工具,成功地达成了项目目标,取得了良好的直接和间接的经济效益,为企业实现"整机不油漆"目标提供了有力保障。     

精益六西格玛在车用电气产品公司的应用

近年来,精益六西格玛（Lean＆SixSigma）在全世界范围内被广泛推广开来,其作为一种先进的管理方式,能够极大地降低制造成本、缩短产品开发和生产周期、提升产品品质、增强企业的竞争能力,并最终能给企业带来巨大的经济效益。对“精益六西格玛”理论的形成、构成的特点和推进方法,及其在车用电气产品公司的实际应用现状做了综述和探析。     

采用数字CMOS工艺实现的1.2-V, 84-dB Σ? ADM设计

由于采用一种全补偿耗尽电容,本文实现了一种基于数字工艺实现的低压低功耗∑?模数调制器。与混合信号工艺相比,该电路所以更适合于纯数字应用。采用新型伪两级Class-AB型运算放大器实现低压低功耗设计目标。在SMIC 0.18μm 1P6M 数字CMOS工艺下,芯片测试结果表明：1.2V电源电压6MHz采样频率时,调制器的动态范围为84dB,总电路功耗为2460μW。     

含钨超级双相不锈钢连续冷却过程中的析出相

利用Gleeble 3800热模拟试验机对含钨超级双相不锈钢进行了连续冷却试验,利用金相显微镜和扫描电镜电子背散射模式（SEM-BSE）分析了冷却速率对含钨超级双相不锈钢σ析出相的影响。结果表明：冷却速率越小,σ相的析出量越多;在相同冷却速率下,变形后钢中σ相的析出量比未变形情况有所增加;冷却速率超过5.0 ℃/s时可阻止含钨超级双相不锈钢析出σ相。     

创新铸就高质量

该文回顾了质量管理发展的历史,探索了现代企业质量管理中提高产品质量的一种新实践模式,即将6sigma的分析方法与TRIZ的创新理论相结合,彻底地解决矛盾,而不是优化参数,最终达到满意的质量水平。并且通过企业的一个实际案例,来讲解具体的操作办法。     

Reducing the quantity of reworked parts in a robotic arc welding process

Today, the competitive environment of the knowledge age has been replaced with the competitive environment of the industrial age as the rules of the business world are changing completely. The focused issue is to reach to the knowledge as soon as possible, and to process and apply it rapidly. In this context, one of the important goals that the companies try to reach in order to achieve acceleration is the six sigma philosophy. Six sigma is a fundamental continuous improvement methodology aimed at reducing the variation and waste on processes by utilizing statistical methods and techniques efficiently. Global companies are making noteworthy profits by using this method in their processes. The six sigma methodology focuses on process excellence advantages for companies that apply it, to reach profit, to increase productivity and to have larger market share. In this paper, an application of six sigma methodology for reducing the quantity of rework parts for robotic arc welding process is given. The phases of six sigma and their results are indicated in detail. Furthermore, it is also shown how various techniques of six sigma methodology are applied to achieve financial benefits. Copyright © 2008 John Wiley & Sons, Ltd.     

基于六西格玛管理方法提高燃油锅炉汽油比

以浙江中烟工业有限责任公司杭州卷烟厂成功提高燃油锅炉汽油比的实践为例,介绍能源管理项目团队利用六西格玛管理方法,研究企业提高燃油锅炉汽油比的途径,通过对能耗数据进行统计分析,发现隐藏于表象之下的不合理耗能环节,优化设备运行参数,从而实现节能减排降耗.