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排序方式: 共有1997条查询结果,搜索用时 406 毫秒
21.
TUYaping HUANGShanglian 《半导体光子学与技术》1996,2(2):146-149
A suitable fiberoptic sensing array embedded in the smart structure to monitor quasi-distrbuted froces on the structrue in presented in this paper.Artificial neural networks are used in processing of fiberoptic sensing array signals.Fundamental experiments have been done and the results are also given. 相似文献
22.
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
23.
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
24.
S. Küppers 《Accreditation and quality assurance》1997,2(1):30-35
Any analytical data is used to provide information about a sample. The "possible error" of the measurement can be of extreme
importance in order to have complete information. The measurement uncertainty concept is a way to achieve quantitative information
about this "possible error" using an estimation procedure. On the basis of the analytical result, the chemist makes a decision
on the next step of the development process. If the uncertainty is unknown, the information is not complete; therefore this
decision might be impossible. The major problem for the in-process control (IPC) procedure is that not only the repeatability
but also the intermediate precision (which expresses the variations within laboratories related to different days, different
analysts, different equipment, etc.) has to be good enough to make a decision. Unfortunately, the statistical information
achieved from one single analytical run only gives information about the repeatability. This paper shows that the estimation
of the measurement uncertainty for IPC is a way to solve the problem and gives the necessary information about the quality
of the procedure. An example demonstrates that an estimate of uncertainty based on the standard deviations of an analytical
method gives a value similar to one based on the standard deviations obtained from a control chart. Therefore, the estimation
is both a very useful and also a very cost-effective tool. Though measurement uncertainty cannot replace validation in general,
it is a viable alternative to validation for all methods that will never be used routinely.
Received: 24 May 1996 Accepted: 10 August 1996 相似文献
25.
Margaret M. Robins S. Jane Scarll Pauline E. Key 《Accreditation and quality assurance》2006,11(5):214-223
During the last decade, it has become increasingly important that researchers demonstrate that research is conducted to the highest standards. The implementation of quality assurance for research laboratories will enable all fields of research and development to be judged impartially. There are no specific standards for research laboratories but where possible, existing standards can be adapted. This review is structured around two approaches. The first considers research to be a logical extension of testing, and it is assumed that testing standards can be applied methodically to each step in a research project. The second advocates a flexible approach, with research-specific criteria for assessing quality. The important papers published on this topic have been reviewed. The conclusions are that the general quality management approach, encompassed by the ISO 9000 series of standards with the emphasis on customer satisfaction and ‘fitness for purpose’, is suitable for implementing quality assurance in research laboratories. 相似文献
26.
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
27.
With the development of information technologies, various types of streaming images are generated, such as videos, graphics, Virtual Reality (VR)/omnidirectional images (OIs), etc. Among them, the OIs usually have a broader view and a higher resolution, which provides human an immersive visual experience in a head-mounted display. However, the current image quality assessment works cannot achieve good performance without considering representative human visual features and visual viewing characteristics of OIs, which limited OIs’ further development. Motivated by the above problem, this work proposes a blind omnidirectional image quality assessment (BOIQA) model based on representative features and viewport oriented statistical features. Specifically, we apply the local binary pattern operator to encoder the cross-channel color information, and apply the weighted LBP to extract the structural features. Then the local natural scene statistics (NSS) features are extracted by using the viewport sampling to boost the performance. Finally, we apply support vector regression to predict the OIs’ quality score, and experimental results on CVIQD2018 and OIQA2018 Databases prove that the proposed model achieves better performance than state-of-the-art OIQA models. 相似文献
28.
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
29.
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
30.
R. Mathur-De-Vré 《Accreditation and quality assurance》1997,2(2):63-68
There is growing interest in developing a general strategy and quality standards for possible accreditation or certification
of R&D laboratories. This article discusses the scope and limitations of Quality Systems in R&D activities. The extension
of QA to R&D centres in general requires emphasis on project management and scientific competence in addition to quality management
and technical competence.
Received: 11 September 1996 Accepted: 13 November 1996 相似文献