运用TQC方法控制SAWH2043彩电中频滤波器不良品率

本文介绍开展QC小组活动,运用TQC方法控制H2043器件不良品率的基本做法与步骤。通过三个PDCA循环,促使H2043器件不良品率下降4倍,为用户提供了高质量产品。最后拟出了进一步提高产品质量的措施和打算。     

QC小组活动在铁路电力贯通线减少故障次数项目中的应用

针对朔黄铁路沿线地形复杂,贯通线极易损坏造成停电事故的问题,通过质量控制(QC)小组采取PDCA循环法活动后,将月平均故障次数由原来的5.08次下降达到2.8次。此QC小组活动后,优化了朔黄铁路电力贯通线路,提高了电力贯通线供电可靠性,保证了铁路的安全稳定运行。     

浅谈供电企业的QC小组活动

QC小组是质量管理与创新活动最有效的一种组织形式,同时QC小组活动又是企业实现全方位质量管理和万众创新的基本途径.对于供电企业来说,有效开展QC小组活动,能够较好地提升工作质量、解决实际问题、激发创新热情、促进员工成长、获得更高效益.充分利用QC小组活动来加强企业各方面的建设,促进企业又快又好发展,可以说是百利而无一害.本文主要介绍供电企业QC小组活动的相关内容,希望对相关管理者、工作者有所帮助.     

开展QC小组活动应注意的几个问题

1978年以来，我国的QC小组如雨后春笋在全国各行各业蓬勃发展起来。电子行业QC小组活动也是十分活跃的。笔者1991年开始从事质量管理和质量检验工作，多次参加省、市、电子部及国家级成果发表会，并参加、指导了一些QC小组活动，多次获得国家、电子部、省、市电子行业的奖励。为使申子行业QC小组活动上一个新的台阶，现提出活动中应注意的几个问题，与大家共同探讨，不妥之处请批评指正。1选择课题恰当地选题是QC小组活动取得成效的额提，是QC小组活动的第一个步骤，也是小组活动能否取得成效的关键。实践证明，很多小组因选题不当，尽…     

论QC小组活动的生命力

自一九七八年我国推行全面质量管理二十多年来,QC小组活动在全国各个领域得到了蓬勃发展。该项活动在提高产品质量、降低物料消耗、增加经济效益和企业素质等方面取得了很     

提高QC活动普及率

本期推出厦门华联推浪圈QC小组,紧密围绕公司经营方针和用户需求,为切实提高员工素质,鼓励更多员工参与群众性质量管理活动,拓展QC活动领域,提高活动普及率,以QC活动为攻关主题,专挑QC活动的“剌”,促使QC知识得到普及和更新,QC培训覆盖全面,小组活动率达85％以上,QC成果日见增多,全公司效益突出!业绩喜人。 推浪圈QC小组事迹,值得同道学习,如果企业都能有该小组的质量改进精神,全面普及QC活动,全员参与QC实践,那实现企业的经济效益目标,就一定是指日可待。     

QC小组活动如何在电信行业信息化专业中有效发挥作用

QC小组活动在信息化专业开展了几年的时间,经过广泛的参与和不断的总结,QC小组活动已经成为相关专业中群众性质量管理活动的一种有效的组织形式,是提高工作质量、服务质量,提高系统运行质量的有效途径,是职工参加企业民主管理的经验与现代科学管理方法相结合的产物。作为全面质量管理的一项重要工作,QC小组活动正在质量管理工作和企业管理运营工作中发挥着巨大的作用。     

开展群众性QC小组活动努力提高产品质量——确保DZY系列电源设备稳定可靠提高节能效益

前言 根据用户反馈DZY系列稳压电源电容器损坏率高的质量信息,于84年1月成立QC小组攻这一质量难关,选择了“消除电容器损坏率高,确保稳压电源质量”的课题,经过一个PDCA循环使电容器损坏率从25％下降为2％(已发表)。84年6月至今,我组为了继续提高稳压电源的质量,增加节能效益,又决定攻“继续降低电容器损坏率和增加节能效益”的课题,经过二个PDCA循环实现了新的目标。目前DZY系列产品已畅销省内外,获得了广大用户的信誉。     

提高窄脉冲截尾器国产化合格率

本文详细介绍了QC小组通过PDCA的三次循环来实现提高窄脉冲截尾器国产化合格率.     

QC小组活动是质量管理体系有效运行的基石和支柱

我国自1978年开始,在各行各业推行并开展了以提高质量、降低消耗、提高经济效益和人员素质为主旨的QC小组活动。由于它的群众性和科学性,在各行各业中取得了十分可喜的成绩,QC小组活动日益发展,成果大量涌现。对我国经济的发展及全民素质的提高起到了积极的促进作用。     

A Compact Four-Wavelength Quantum-Cascade Laser Source

A four-wavelength quantum-cascade (QC) laser source that operates using a single current channel is presented. The source includes two different heterogeneous cascade QC lasers, one with emission wavelengths of 7.0 $mu{hbox {m}}$ and 11.2 $mu{hbox {m}}$, and the other with 8.7 $mu{hbox {m}}$ and 12.0 $mu{hbox {m}}$ . For 3.0-mm and 3.5-mm cavity lengths, QC lasers with emission wavelengths of 8.7, 11.2, and 12.0 $mu{hbox {m}}$ have threshold current densities within less than a factor of 2, which allows them to be conveniently driven in series by a single current source.      

Characterization of Quantum-Cascade Lasers Using Single-Pass Transmission Spectroscopy

The study of the electron distribution and intersubband transitions in quantum cascade (QC) lasers provides fundamental insights into the laser operation. Measurements on intersubband transitions are often performed on QC lasers under nonoperating conditions, i.e., at zero electric field. In this study, a single-pass transmission technique that allows for probing of QC lasers under operating conditions was used. The measurements and analysis were done on QC lasers with vertical and diagonal transition active region designs operating at $lambdasim 10 mu{hbox {m}}$. The single-pass modal gain coefficients, extracted for the vertical transition design, were 24.04 cm/kA at 100 K, 21.36 cm/kA at 125 K, 14.25 cm/kA at 150 K, and 5.26 cm/kA at 175 K.      

Bound-to-continuum GaInAs-AlAsSb quantum cascade lasers with reduced electric injection power density

Short-wavelength (/spl lambda/<4 /spl mu/m) GaInAs-AlAsSb quantum cascade (QC) lasers have been demonstrated using a "bound-to-continuum" design for the purpose of reducing the electric injection power density. As a result, we have reduced the low-temperature electric injection power density of the lasers by 40%, compared to that of GaInAs-AlAsSb QC lasers emitting at the same wavelength but adopting a triple-quantum-well design. The lasers in the present report can operate up to room temperature (300 K) in pulsed mode, emitting at short-wavelength /spl lambda//spl sim/3.7-3.9 /spl mu/m.     

纤锌矿准一维GaN/AlxGa1-xN量子阱线中的极化准受限光学声子模

基于介电连续模型与Loudon的单轴晶体模型,推导分析了纤锌矿准一维量子阱线中的准受限(QC)光学声子模及相应的电子-QC光学声子之间的相互作用函数.对一个AlN/GaN/AlN纤锌矿量子阱线进行了数值计算.结果显示,当体系的角量子数m与z方向上的自由波数kz较小时,QC光学声子模的色散相当明显.观察到纤锌矿量子体系中的QC光学声子模的"退化"行为.通过电子-QC光学声子之间的耦合函数的讨论发现,高频区中的低频支QC模在电子-QC光学声子模之间的相互作用中起主要作用.计算结果还证明自由波数kz与角量子数m对电子-QC光学声子模间的耦合特性具有相似的影响.     

Polarization mode control of two-dimensional photonic crystal laser having a square lattice structure

We investigate in detail control methods of polarization mode in a two-dimensional square-lattice photonic crystal laser. In order to control the polarization mode using the square lattice, we investigate the eigenmode of the electromagnetic field against the possible symmetry groups of a square lattice. Both the electromagnetic field distributions of lasing oscillation mode and the band diagram are significantly influenced by the symmetry groups. In the case of the square lattice structure, symmetries "p1", "pm", "p2", and "pmm" are suitable for obtaining the unidirectional polarization mode. Among these symmetry groups, the symmetry group "pmm" is especially interesting considering the simplicity of the eigenmode of the electromagnetic field. In order to obtain the symmetry group "pmm", we deform the unit cell structure of a square lattice from circular to elliptical and investigate the properties of symmetry group "pmm" in detail. The elliptical ratio of the unit cell structure can modify the coupling balance of a lightwave propagating in two perpendicular in-plane directions and can control the eigen energy of each band edge.     

High performance injectorless quantum-cascade lasers

Injectorless quantum-cascade (QC) lasers, for the first time comparable to conventional QC lasers, are presented. The samples are based on InP and the active region is designed as a four-level staircase, realised in the strain-compensated material system Ga/sub 0.4/In/sub 0.6/As/Al/sub 0.56/In/sub 0.44/As. Low threshold current densities and a maximum operating temperature of 350 K have been achieved, due to an optimised design. At 77 K the wavelength is about 10 /spl mu/m, while threshold current densities of 0.9 kA/cm/sup 2/ have been observed, which compare well with those of conventional QC lasers in this wavelength region.     

光通信中一种基于有限域循环子群的QC-LDPC码构造方法

基于有限域循环子群方法提出了一种结构简单,可以灵活选择码长、码率,并且编译码复杂度低的准循环低密度奇偶校验(QC-LDPC)码构造方法。利用此方法构造出适合光通信系统传输的规则QC-LDPC(5334,4955)码。仿真结果表明该码型利用和积迭代译码算法在加性高斯白噪声信道中取得了很好的性能,比已广泛应用于光通信中的经典RS(255,239)码具有更好的纠错性能。因此所构造的QC-LDPC(5334,4955)码能较好地适用于高速长距离光通信系统。     

基于PDCA循环模型的项目管理系统的设计与实现

PDCA循环是一个持续改进模型,它包括持续改进与不断学习的四个循环反复的步骤,即计划(Plan)、执行(Do)、检查(Check/Study)、处理(Act)。通过构建中国银联某项目管理信息系统的实例,介绍了在,NET平台下,采用PDCA循环模型构建应用系统的设计思想和实现方法。     

Start-oscillation conditions in modulated and unmodulated O-type oscillators

The starting conditions for the O-type backward-wave oscillator are computed for large values of C, QC and d, using both digital and analog methods. A general method of solving complex polynomials called the "downhill" method is applied both to the secular equation and then to the RF voltage equation to obtain starting conditions. The analog computer is used to solve simultaneously, by trial and error method, the linear circuit and ballistic differential equations. The analog method is applied to the modulated BWO in order to determine the effects of modulations on the starting conditions. Extensive calculations of BWO starting conditions have been made for a wide range of C, QC and d.