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91.
本文研究建立全国性的“中国质量信用信息平台”的基础条件;分析在当前质量监督管理组织架构下建立平台的困难;探讨了如何跨地域、跨部门协作采集产品及其质量信息,并保证其权威性;最后总结了各方在协作中的角色与分工. 相似文献
92.
针对自控专业工程项目设计文件在编制过程中出现的质量问题进行深入分析,根据分析结果引入数据库技术并且采用软件编程的手段对设计过程中的各个环节进行优化,不仅提高了设计文件的质量,同时也提高了设计文件的准确率与设计的工作效率。 相似文献
93.
以D irect U i为核心,逐步分析了工业组态的框架构建过程,并分析了如何实现组态各个组件的步骤。通过该组态,可实现组态与其他软件模块的良好融合,生成原生机器码,大大提高软件运行效率。 相似文献
94.
提出了建立检测技术数据库的方法,介绍了软件的结构及功能,为检测技术更好地服务提供一个基础数据平台。 相似文献
95.
Speed of sound of ionic liquids: Database,estimation, and its application for thermal conductivity prediction 下载免费PDF全文
Speed of sound is an important thermodynamic property of ionic liquids (ILs) and always chosen as a source to determine other properties. A database for the speed of sound of pure ILs created by collecting experimental data from literature covering the period from 2005 to 2013 is presented. The effects of temperature and the alkyl chain length on the speed of sound are discussed and a second‐order corresponding states group contribution method is developed to estimate the speed of sound. An average absolute deviation (AAD) of 2.34% has been obtained. This method offers a simple but reliable approach to estimate the speed of sound of new ILs. Finally, the speed of sound is used to determine the thermal conductivity of ILs based on the Bridgman theory. The calculated values of thermal conductivity show a good agreement with the experimental ones with an AAD of 3.91%. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1120–1131, 2014 相似文献
96.
Distraction and inattention are considered to be very important and prevalent factors in the causation of road accidents. There have been many recent research studies which have attempted to understand the circumstances under which a driver becomes distracted or inattentive and how distraction/inattention can be prevented. Both factors are thought to have become more important in recent times partly due to the evolution of in-vehicle information and communication technology. This study describes a methodology that was developed to understand when factors such as distraction and inattention may have been contributors to crashes and also describes some of the consequences of distraction and inattention in terms of subsequent driver actions. 相似文献
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Ionic discotic liquid crystals are salts of discotic liquid crystals that may display lyotropic and thermotropic mesomorphism. Columnar structures of π-π stacking ionic discotic liquid crystals function not only as anisotropic organic semiconductors, similar to their neutral analogues, but they may also efficiently conduct ions. This combination of electronic and ionic conduction is only one of several unique properties that these materials may display, but their systematic investigation has been limited because of their often complex synthesis, purification, and characterization. However, a comprehensive account of existing reports on ionic discotic liquid crystals is not straightforward, despite their relatively small number, because publications are scattered across different areas of research, such as liquid crystals, ionic liquids, and ionic self-assembly. This review intends to provide a concise but comprehensive overview of the published work on ionic discotic liquid crystals and related compounds and is expected to stimulate further exploration. Highlighted in this review is the mesomorphism of ionic discotic liquid crystals and its dependence on structural changes, which is also the focus of most reported studies. Particular attention was given to the dependence of mesomorphism on the location and types of the charged groups as these are parameters unique to these compounds. Also described are electronic, optical, and other properties of these materials if reported. 相似文献