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51.
ERP和ISO9000的一体化结合是一个值得重视的研究课题.文中首先分析了ERP和ISO9000的对应点,指出两者可以相互支撑.最后,探讨了两者的集成实施问题.  相似文献   
52.
This International Standard describes three methods for measuring the lateral resolution achievable in Auger electron spectrometers and X‐ray photoelectron spectrometers under defined settings. The straight‐edge method is suitable for instruments where the lateral resolution is expected to be larger than 1 µm. The grid method is suitable if the lateral resolution is expected to be less than 1 µm but more than 20 nm. The gold‐island method is suitable for instruments where the lateral resolution is expected to be less than 50 nm. The standard contains three informative annexes that provide illustrative examples of measurements of lateral resolution. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
53.
In analytical chemistry, proficiency testing usually consists in tests that laboratories conduct under routine conditions and report the result to the PT provider who then converts the result to a score which helps the participant to assess the accuracy of the result. The aim of this work is to show PT providers, accreditations bodies, and participating laboratories that different scoring results can be achieved depending on the evaluation system selected. The influence of different evaluation techniques on the results of an interlaboratory comparison for determination of gold in precious metals alloys was investigated. Results from 19 participating laboratories were evaluated by means of the three procedures: (1) classical statistical approach—outliers detection; (2) robust methods—(2A) robust procedure and (2B) ISO 13528; and (3) fitness for purpose. Evaluation of the same PT data revealed very interesting issues depending on the different scoring systems that were used and the robustness of the statistical methods used for detecting outliers. As a general rule, laboratories with scoring Z > 2 offered clearly poorer performance in robust approaches than classical ones. In order to support this first evidence, we evaluated a second data set with results from 24 laboratories (mercury from soil samples) by means of the four mentioned approaches. Selection and comparison of different scoring systems must be done very carefully, because sometimes they are not the best approach for studying the data population or the more appropriate one for evaluating the distribution of the data. Finally it should be taken into account that sometimes the robust scoring systems are not always suitable for evaluating the results of some PT schemes.  相似文献   
54.
The topic of validation is diversified. This review outlines the validation strategies which can be found in national, international and supranational regulations, compares them with one another and aims to elaborate on the main principles. European regulations and legislation, Codex alimentarius guidelines, the official methods program of the AOAC, and naturally the relevant ISO standards, particularly the ISO 5725 series, are taken into consideration. The objective of every validation is to demonstrate fitness for purpose. This varies of course in its characteristics for the diverse uses. However, all approaches have in common the objective of harmonisation of food control by using effective and reliable methods. To this end, criteria are determined and validation models developed and made compulsory. ISO 5725 is the central basis for validations for quantitative methods with its validation specifications through method collaborative studies. On the contrary, there are no valid uniform international method specifications for qualitative methods. Collaborative studies are in opposition to single-lab-validations with different sources of error. Whereas laboratory errors are predominant in collaborative studies, the single-lab-validation or in-house validation concentrates particularly on time and processing errors (intermediate precision). In new statistical models for in-house validations, the matrix mismatch error is also considered. The validation models presented here are of a general nature and can be used in principle for all analytical methods. Correct and appropriate statistical modelling is very important.  相似文献   
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56.
张亚聪  管继富  张天一  宿峰荣 《应用声学》2017,25(1):141-143, 148
车载控制器电源部分的可靠设计是保证控制器正常工作的关键。其中,车辆电气环境中沿电源线的瞬变传导骚扰是造成车载控制器失效的一个重要原因。为了实现对车载控制器电源部分瞬态传导干扰的抑制,同时通过国际标准ISO 7637-2《道路车辆——由传导和耦合引起的电骚扰:第2部分沿电源线的电瞬态干扰》的测试,对车载控制器浪涌抑制及电源保护的几类常用设计电路进行了研究,比较了各自的优缺点,再结合ISO 7637-2的测试经验,提出了一种简单可靠的浪涌抑制电路的综合性设计方案。试验证明该电路设计能够完全通过ISO 7637-2的测试,特别是能够连续通过5a测试脉冲,具有良好的浪涌抑制性能及很高的可靠性,与设计要求相吻合,可以广泛地应用于车载控制器的电源保护和浪涌抑制上。  相似文献   
57.
Due to a high center of gravity (CG) location, agricultural vehicles are more vulnerable to overturns. The CG location can be calculated using the lifting axle method of ISO 16231-2:2015. But, as a vehicle is lifted, its liquid payloads are not entirely contained. The liquids will shift both in position and form, affecting the CG height calculation.A mathematical model was developed to predict the effect of liquid movement on the CG height calculation of a tilted vehicle. The model was validated using an agricultural utility tractor and a prototype. The developed model was applied to calculate the CG location considering the effect of the liquid shift.Results showed tilting produced a higher calculated center of gravity due to liquid movement, but by increasing the tilting angle, the calculated CG height decreased. The effect of the liquid shift on CG height measurement for the wagon with 16.0% liquid mass was 14.8% and for the tractor with 1.2% liquid mass was 0.41%. The model error was less than 1.3% for all tests. Considering the effect of the liquid shift in CG height calculation, the error in CG height calculation decreased from 11.9% to 2.6% for the wagon.  相似文献   
58.
Wool is considered to possibly exhibit antibacterial properties due to the ability of wool clothing to reduce the build-up of odor, which arises from the microbial activity of skin microbiota. Indeed, when tested with a widely used agar diffusion plate test method, even wool or other textiles not treated with any antimicrobial agent can be interpreted to show certain antibacterial effects due to the lack of growth under the specimen, as instructed in ISO 20645:2004 standard. Therefore, we analyzed in detail what happens to bacterial cells in contact with untreated wool and cotton fabric placed on inoculated agar plates by counting viable cells attached to the specimens after 1 and 24 h of contact. All wool and several cotton samples showed no growth under the specimen. Nevertheless, it was shown without a doubt that neither textile material kills bacteria or inhibits cell multiplication. A reasonable explanation is that bacterial cells firmly attach to wool fibers forming a biofilm during multiplication. When the specimen was lifted off the nutrient agar surface, the cells in the form of biofilm remained attached to the wool fibers, removing the biomass and resulting in a clear, no growth zone underneath it. By imaging the textile specimens with X-ray microtomography, we concluded that the degree of attachment could be dependent on surface topography. The results indicate that certain textiles, in this case, wool, could exhibit antibacterial properties by removing excess bacteria that grow on the textile/skin interface when taken off the body.  相似文献   
59.
The motives for and the implementation of a quality system complying with the requirements of the ISO/IEC 17025 standard in a gamma-ray spectrometry laboratory are briefly described, as well as its influence on the laboratory's work and output. The use of the quality system as a tool for managing and controlling the state of the laboratory is described. Two examples of control and improvement of the laboratory's performance are given.  相似文献   
60.
ISO Technical Report 19319:2003 contains information on the determination of lateral resolution, analysis area and sample area viewed by the analyser in surface analyses by Auger electron spectroscopy and x‐ray photoelectron spectroscopy. This article provides a brief summary of this information. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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