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11.
12.
Solveig Linko 《Accreditation and quality assurance》2002,7(2):55-59
Internal audits inherently effect quality improvement, and concrete results can be expected by careful planning. As audits
should improve the quality system in situ, the development of audits should not be neglected. ISO/IEC 17025 describes the
objectives of internal audits and management reviews in more detail compared to the former standards EN 45001 and ISO/IEC
Guide 25, although the main features are unchanged. This addresses continuous surveillance of the current practice. A brief
questionnaire on vertical audits was distributed to 74 of 120 employees at a Finnish private medical laboratory, Medix Laboratories
Ltd. A positive feed-back was received from the current management of audits. However, the study revealed that continuous
supervision of audits is needed. Many employees were not willing to perform audits if they had no previous experience. Additionally,
audits performed at the workbench were not considered as the best possible for fruitful discussions.
Received: 20 February 2001 Accepted: 30 November 2001 相似文献
13.
HT-7中性束诊断电源系统的计算机控制系统由PLC、工控机、逻辑控制和定时单元等组成。对起弧、束流引出等实验进行了研究。在多种参数下,通过调节弧压、进气量等观察了其对弧流的影响。初步实验结果表明,在高压35kV、弧流80A的情况下,束电流可以达到3.6A,引出的中性束流功率可以稳定地达到50kW以上。 相似文献
14.
A five-step model for a quality assurance system is developed for an internal quality control check. It includes the quality
control of the decomposition method and the detection method as steps belonging together. The Wickbold combustion technique
as decomposition method in combination with atomic absorption spectrometry was chosen. The vaporization of the elements mercury,
arsenic, lead, antimony and selenium is based on combustion in an oxyhydrogen flame. To check the efficiency of the analytical
system, the uncertainty of results was calculated on the basis of the "Guide to the Expression of Uncertainty in Measurement".
Received: 13 January 1997 · Accepted: 29 March 1997 相似文献
15.
Reliable, traceable and comparable measurements provide the rational basis for evaluation of the quality of a result and
the starting point for recognized laboratory accreditation in any national area. Modern medical diagnostics and treatment
involve rapidly rising numbers and types of clinical laboratory measurements, that are reliable. Therefore, the basic principles
to be followed to assure the traceability of clinical measurements as required by the Romanian Laws of Metrology are reviewed.
Main sources affecting the quality of the unbroken chain of calibrations that relate the measurements back to appropriate
measurement standards are discussed. Examples of how to achieve traceable measurements in clinical laboratories are presented.
Details of specific uses of reference materials, measuring instruments and standard measurement methods are also discussed.
Received: 8 January 1998 · Accepted: 21 April 1998 相似文献
16.
James O. Westgard 《Accreditation and quality assurance》2004,10(1-2):10-14
For optimal performance of laboratory tests, testing processes should be designed to provide clinically useful quality and QC procedures should be selected to assure that the necessary clinical quality is achieved in routine production. One important issue is how to define clinical quality. Today’s practice guidelines, quality regulations, and quality standards provide some targets for analytical quality, but they fail to adequately address clinical quality. Target values for precision and accuracy are not the same as clinical quality, though analytical performance certainly contributes to the clinical quality of test results. How can we proceed in our quest to improve quality when there are inconsistencies and inadequacies in the specifications found in practice guidelines, regulations, and standards? Today target values are often being set for the wrong targets. A better approach is possible if we focus on test interpretation guidelines to define clinical quality, then derive specifications for the accuracy and precision that are appropriate for the method, as well the QC rules and numbers of control measurements that are necessary to guarantee the desired quality will be achieved in routine operation of the testing process. 相似文献
17.
Given n samples(viewed as an n-tuple) of a γ-regular discrete distribution π,in this article the authors concern with the weighted and unweighted graphs induced by the n samples. They first prove a series of SLLN results(of Dvoretzky-Erd¨os’ type). Then they show that the vertex weights of the graphs under investigation obey asymptotically power law distributions with exponent 1 + γ. They also give a conjecture that the degrees of unweighted graphs would exhibit asymptotically power law distribu... 相似文献
18.
Hongwei Liu Xiangdong Liu KeXue Yuan KeSong Hu Yutau Chen 《International Journal of Infrared and Millimeter Waves》1993,14(8):1693-1699
A five-channel grating spectrometer for use in millimeter wave band (25100GHz) is described with its design theory of optical path, and measured results of insertion loss and resolving power. 相似文献
19.
Medical laboratories of the public sector as well as of the private sector on the island of Mauritius are preparing for accreditation. The clinical laboratory of the Central Health laboratory of the Ministry of Health and Quality of Life has undergone a pre-assessment by experts of the International Atomic Energy Agency (IAEA) through the aegis of a project targeted to members of the Africa Region. Several shortcomings were identified and respective corrective actions were recommended for implementation within a given time frame. In addition to ensuring the competence of the laboratory, accreditation has various positive aspects such as an increased awareness of the staff to quality and better training opportunities. The pre-assessment exercise has provided a gap analysis, which is an important aspect in the preparation towards accreditation. 相似文献
20.
J. Forstén 《Accreditation and quality assurance》1998,3(7):285-288
This article mainly focuses on the testing of products, materials, etc., but the general principles are applicable in a broader
perspective. Quality of testing should be judged based on fitness for purpose. This judgement includes both objective and
subjective elements. The possibility to make decisions and other professional judgements based on test results alone is discussed
and compared with the decisions and judgements being made through the certification and inspection process. Quality, including
the uncertainty of the test results, depends on many factors, and in order to make necessary improvements in the testing procedures
based on the customers' needs, the right issues should be addressed. The question arises as to whether, in laboratories' quality
systems and in the accreditation and certification process, attention is really paid to those factors that are crucial to
obtaining reliable results. 相似文献