再使用产品的质量判断研究

再使用产品是回收产品再利用的第一优先级.给出了再使用产品的定义,并利用数据包络分析方法对其进行了质量判断.通过案例分析,说明该模型用于再使用产品质量判断是可行的和有效的.     

镜面物体往复通过弱湍流大气系统的成像

分别利用部分相干理论、以广义随球波函数为基础的Ｋａｒｈｕｎｅｎ－Ｌｏｅ′ｖｅ展开和相干成像理论研究了弱湍流像差大气照明系统互强度函数传输特征和位地湍流介质中镜面物体成像规律。结果表明：仅当反射光束相干尺度（成像光束等效直径）小于成像孔径的尺度时才能改善湍流大气中两次成像的质量。     

Impact of Statistical Multiplexing on Voice Quality in Cellular Networks

This paper examines the quality of transmission of voice over cellular, packet-switched networks. The medium access mechanism in the uplink is simulated under various statistical multiplexing scenarios in order to assess the effect of front-end clipping on voice quality. Moreover, the simulation is implemented in a real-time demonstration platform utilized to acquire subjective indicators of voice quality by performing Mean Opinion Score (MOS) tests. Results from the MOS tests are reported, and an analysis of the obtained speech samples is presented. Finally, the results are summarized and potential further directions for the simulation tool and the speech models are discussed.     

用模糊集方法计算工程质量等级确定质量系数

采用工程模糊集理论方法,用科学合理的数字来衡量工程质量.提出将专家定量评分法与定性评议法科学地统一起来,使权重的确定更为合理与科学.同时,用实例进行实证分析.     

Calibration bias in the determination of polynuclear aromatic hydrocarbons in water

 We present the results of an investigative interlaboratory test to determine the reasons for poor agreement between data from different laboratories for the determination of polynuclear aromatic hydrocarbons in water. Received: 2 July 1998 · Accepted: 1 August 1998     

How valid are our QA assumptions: an examination of underpinning Axioms

 There is no universally accepted approach to analytical quality assurance (QA) and different laboratories place emphasis on widely different aspects. The difficulties in agreeing what constitutes best practice originate, in part, from a lack of clarity concerning the underpinning principles or axioms. This paper aims to set out some of the axioms which underpin current thinking and to discuss their validity and interplay, in order to provide a more rational, or at least transparent basis, for the evaluation of different strategies. The selection of issues and the discussion are necessarily subjective and based on the authors experience. It is concluded that current practice is generally soundly based but there is a need for a better understanding of the efficacy and cost-benefit of the various QA techniques available. Scepticism concerning the value of systems and documentation is not well founded, provided they are not taken to excess. There are, however, issues concerning the military-based command-and-control style and the engineering origins of ISO 9000 and ISO Guide 25 requirements which make them not entirely suitable for a modern analytical laboratory. There are also dangers that the command-and-control style could discourage measurement scientists from thinking for themselves or lull them into a false sense of security. Received: 24 December 1998 · Accepted: 18 May 1999     

Sense and nonsense of laboratory accreditation

 An open mind is essential for the implementation and improvement of total quality management. Leadership, as such, is of no value without a vision concerning corporate culture and human resources. Therefore, constant communication between partners within a corporate body is the cornerstone for empowerment. The evaluation of ideas and complaints is considered to be essential for the identification of strengths and weaknesses of a system, whereas, competition and benchmarking may reveal surprising opportunities for improvement. We discuss the idea that customer-oriented efficiency in a hospital environment may be classified as a critical success factor.     

模糊数学方法在矿井自然地质条件评价中的应用

运用模糊数学理论，对直接制约煤矿开采与生产经济效果的矿井自然地质条件的评价原理和方法进行了一些探讨     

直纹曲面的性质及其在工程中的应用

由一族或几族直线所构成的曲面叫做直纹曲面.本文给出了直纹曲面的判定定理,讨论了直纹曲面的方程与直母线方程的关系.综合研究分析了直纹曲面的性质,包括直纹曲面的基本性质和特殊性质.探讨了直纹曲面在建筑工程、电力工程、通信工程、水利工程和日常生活等方面的实际应用.     

Proficiency testing in analytical chemistry, microbiology, and laboratory medicine – working group discussions on current status, problems, and future directions

Working group (WG) discussions on proficiency testing (PT) held at the joint Eurachem/ EQALM workshop, Borås, Sweden, 24–26 September 2000 are summarized. The discussions focused on aspects of PT and accreditation (WG 1), general aspects of PT in analytical chemistry (WG 2), microbiology (WG 3), and laboratory medicine (WG 4), incorporation of measurement uncertainty into PT schemes (WG 5), international harmonization of PT schemes (WG 6), and the role of PT in the international structure of chemical measurement (WG 7). Current status, problems and future directions are identified. Each WG contained a majority of participants experienced in the subject being covered by that WG, and a few participants with different expertise. This was done to promote cross-fertilization of ideas between sectors, a key objective of the workshop. The WG issues reflected the content of the keynote lectures and some issues were covered from different perspectives by more than one group.