流程驱动的质量保证

在全球经济日趋一体化的背景下，对于面对激烈竞争的通信设备制造商而言，如果其产品与服务质量达不到世界级水平，将难以在国际市场的竞争中取胜，在无法使用关税壁垒等保护政策的情况下，甚至难以在国内市场站稳脚跟。因而产品质量已经成为通信设备企业长久发展的重要主题之一。     

Quality control of measurements—Measurement assurance

The ability to relate individual measurements to nationally accepted standards is a requirement of traceability. This paper discusses a perspective in which the goals of traceability are viewed in terms of performance requirements on measurement quality as reflected in a statement of uncertainty.     

Quality assurance system and reliability testing of LSI circuits

The development of LSI circuits as well as their quality and reliability assurance in the current production require, due to the specified high quality levels, a precisely defined Quality Assurance System. Such a System was presented in the first two Sections.For the predictions of field failure rate generally the time-temperature acceleration in accordance with the Arrhenius model has to be applied. Field reliability at lower operating temperatures has to be determined from the results and defectives of sampling life-tests at elevated temperatures. Obviously for LSI circuits the time-temperature acceleration depends very strongly on different failure mechanisms involved. For this reason an efficient and correct failure rate prediction can only be performed, if the failure mechanisms in the defective chips are exactly known and classified.     

Quality assurance of voice over WLANs (VoWLANs) with differentiated services

Several technical issues make commercial and large voice over wireless local area network (VoWLAN) services difficult to provide. The most challenging issue when voice over Internet Protocol (VoIP) services are ran over IEEE 802.11-based WLANs is the bandwidth inefficiency due to the considerable overhead associated with WLAN packet transmission. In this work, we propose a session-based quality-of-service management architecture (SQoSMA) to overcome the low number of VoIP calls in IEEE 802.11 Wireless LANs and the negative effect of new call addition when the WLAN reaches its capacity. The SQoSMA combines data and control planes to detect VoWLAN QoS degradations and performs either an adaptive audio codec switching or a call stopping to fix VoWLAN issues in a differentiated services manner. In addition, our solution deals with user sessions information, by considering user priority (from its agreement) to guarantee a certain level of its multimedia applications. Performance evaluation using a real test-bed shows that call codec change and call stopping techniques can easily assure high-priority calls with acceptable call blocking probability.     

脉冲电容器质量试验及其电路中元件参数的确定

介绍了在一定电压、电流值和反峰电压下的充放电试验方法,并经过深入分析归纳出设计电路中L,R元件参数的公式,为测试某型号脉冲电容器的质量及工作可靠性提供了依据.实验要求脉冲电容器充电电压10 kV,放电电流4 kA,重复频率可调6～10s/次,测试5000次.充电电源来用恒流充,具有速度快,效率高,对电容损伤小等优点,开关采用高压真空接触器;智能控制器来用FPGA控制,具有控制灵活,稳定性高,测量精度高等优点.放电回路是在RLC二阶电路欠阻尼状态下进行的.通过仿真,验证了元件参数设计正确.     

加强信息安全保障工作--全国信息安全保障工作会议在北京召开

在国家信息安全建设快速推进的重要时刻,全国信息安全保障工作会议近月在北京召开,中共中央政治局常委、国务院副总理黄菊作了重要讲话,他强调了信息安全保障工作的极端重要性,明确了今后一段时间我国信息安全保障工作的主要任务。     

Service assurance in modern telecommunications networks

Modern telecommunications network design and examples of possible causes of service interruption are examined, using AT&T 800 Service for illustration. Different methods of assuring service technically are presented. It is shown how end-to-end service reliability can be improved by using the techniques described, applying them to 800 Service as an example. Techniques used to restore generic switched services or private line services after a failure within a network are also presented     

SW-CMM2中的软件质量保证

随着信息技术的发展,软件已成为大多数产品的重要组成部分,如何提高软件质量,使软件更好地服务于各种应用需要,已成为各行各业广泛关注的课题。重点讨论了软件企业或组织实施CMM2中的关键过程域-软件质量保证(SQA)的目的、活动、实施方法和可能遇到的问题。提出了实施SQA的方法和步骤。     

Software quality assurance considerations

Very few articles dealing with software quality assurance have been published over the past few years; these have been primarily from the military and medical industries. It is interesting to note that many of the topics included or suggested in these articles are presently not in use and the concepts are “relatively unknown”. Effective statistical techniques are basically lacking unfortunately. The “real key” is to understand that software quality assurance is “10 years behind the hardware” as stated by an SWQA department manager in a large military products (DOD) facility. Thus the intent of these offerings is to share some ideas in a very complex and challenging arena; this concept, this methodology has not been able to keep up with the rapid advances required of it and imposed by the primary systems.     

Measurement assurance and accreditation

The National Bureau of Standards (NBS) has developed a concept to accredit laboratories which provide electromagnetic power, attenuation, and reflection coefficient calibration services. This program, developed under the general procedures of the National Voluntary Laboratory Accreditation Program (NVLAP) would accredit calibration laboratories for levels of uncertainty equivalent to the uncertainties of measurements made at NBS. Implementation of the program is being delayed pending funding to implement a Measurement Assurance Program (MAP) by NBS. The MAP is a quality assurance program to establish and monitor the uncertainty of measurements being made by participating laboratories on a continuing basis.     

Software quality assurance considerations

Software quality assurance is a key aspect for bringing on line any software system. Even today with the new approaches in quality and in computers, there are still many techniques and new dynamics. To most, this area is not understood well if at all. In dealing with this important topic, we have used a somewhat unusual approach; we have summarized several important, selected articles dealing with the various aspects of this critical topic.     

软件确保研究进展

对软件确保的概念进行了介绍,指出软件确保主要聚焦于软件的安全性(security)、保险性(safety)、可靠性(reliability)和生存性(survivability),并以此为基础,提出了S3R软件确保模型,然后在战略层面上讨论了软件确保的发展过程,重点阐述了美国国土安全部、美国国防部、美国宇航局的软件确保计划;在技术层面上探讨了确保软件S3R性质的相关技术进展,阐述了正在制定中的软件确保标准.最后指出了软件确保的发展趋势.     

国家信息中心信息安全研究与服务中心副主任叶红提出:要加强信息安全保障体系中的数据修复

在海量信息覆盖的今天,许多单位或个人都在为数据的丢失而担忧和困惑。为此,国家信息中心信息安全研究与服务中心副主任、高级工程师叶红就数据恢复的现状、市场需求和发展趋势三个问题作了全面的阐述。 第一,数据应急修复已被纳入国家信息安全保障体系计划中,同时数据恢复也滋生出了一个新的市场需求。这一市场潜力很大,国内外     

System assurance in a rapid transit system

System Assurance is a critical issue in the development of new rapid transit systems. This is especially vital when the system is completely automated, i.e. unmanned. An outline of a system, the terminology, plans and methodology used in the development of reliability and maintainability programs for the rapid transit system are discussed.     

激光冲击强化的冲击波幅值和飞行时间的测量

为了研究不同激光功率密度下空气中冲击波幅值和飞行时间分别与工件中冲击波幅值和残余压应力的变化关系,采用工件为45#钢、铝箔为吸收层、水为约束层、声发射传感器和聚偏氟乙烯压电膜传感器同时对空气和工件中的激光诱导等离子体冲击波进行测量。结果表明,随激光功率密度的增加,空气中冲击波飞行时间非线性的减少,空气和工件内冲击波幅值非线性的增加,工件中残余压应力值接近饱和。进行多项式拟合,获得了空气中冲击波幅值与工件内冲击波幅值、空气中冲击波飞行时间与工件内残余压应力的经验公式,为激光冲击强化质量评估提供一定的理论参考。