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81.
82.
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
83.
Modeling the effect of liquid movement on the center of gravity calculation of agricultural vehicles
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
84.
Tomislav Ivankovic Antonija Rajic Sanja Ercegovic Razic Sabine Rolland du Roscoat Zenun Skenderi 《Molecules (Basel, Switzerland)》2022,27(6)
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
85.
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
86.
《Surface and interface analysis : SIA》2004,36(7):666-667
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
87.
A procedure for estimation of measurement uncertainty of photometric analysis based on the ISO GUM method is presented. Two variations of the procedure—for the calibration graph and the standard addition method, respectively—are discussed. The variations are based on mathematical models involving 64 and 80 input quantities, respectively. The uncertainty of the result strongly depends on changes in experimental details. These dependencies are explored for a practical example of determination of the iron content of aluminum. The importance of taking uncertainty from sample preparation into account in uncertainty estimation is stressed. The number of effective degrees of freedom is calculated and discussed. The examples are available as GUM Workbench files in the Electronic Supplementary Material.Electronic Supplementary Material Supplementary material is available for this article at .
相似文献
Ivo LeitoEmail: Phone: +372-7-375259Fax: +372-7-375264 |
88.
The history since 1992 and the current state of affairs of the Russian Accreditation system for analytical laboratories are described. Some national characteristics of the implementation of the ISO/IEC 17025 Standard in Russia are considered. The elucidation of some ISO/IEC 17025 Standard prepositions is presented to facilitate implementation of the Standard by accreditation bodies and analytical laboratories claiming accreditation. 相似文献
89.
《Surface and interface analysis : SIA》2006,38(3):178-180
ISO 18118 provides guidance on the measurement and use of experimentally determined relative sensitivity factors for the quantitative analysis of homogeneous materials by Auger electron spectroscopy (AES) and X‐ray photoelectron spectroscopy (XPS). This article provides a brief summary of this International Standard. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
90.
《Surface and interface analysis : SIA》2005,37(5):524-526
International Standard ISO 19318 specifies the minimum amount of information describing the methods of charge control and charge correction in measurements of core‐level binding energies for insulating specimens by x‐ray photoelectron spectroscopy, which is to be reported with the analytical results. Information is also provided on methods that have been found useful for charge control and charge correction in the measurement of binding energies. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献