首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   64篇
  免费   3篇
化学   6篇
综合类   1篇
数学   39篇
物理学   21篇
  2022年   1篇
  2021年   1篇
  2016年   3篇
  2014年   2篇
  2013年   4篇
  2012年   4篇
  2011年   4篇
  2010年   6篇
  2009年   7篇
  2008年   10篇
  2007年   9篇
  2006年   1篇
  2005年   1篇
  2004年   1篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1995年   4篇
  1989年   1篇
  1988年   1篇
排序方式: 共有67条查询结果,搜索用时 15 毫秒
1.
检验检测服务模式发展滞后于检验检测行业发展的重要原因之一就是缺乏针对于服务模式的理论定义。采用概念分析法,以服务模式的定义和检验检测行业的服务特点为逻辑,研究了相关的代表性理论,认为服务模式主要由服务的基本要素和服务的商业模式两方面的内容组成,并深入探讨了检验检测的服务模式,提出了构建检验检测服务模式这一概念的重要意义。  相似文献   
2.
胡楠  张吉沐阳  郭健  吴益飞 《应用声学》2016,24(3):95-98, 102
针对配电房等室内电力系统供电设备自动巡检的需求,提出了以微控制器MSP430F5438为核心的自动巡检机器人控制系统总体设计方案。采用模块化方法完成了控制系统硬件电路设计,主要包括:主控模块、电源模块、运动控制模块、通信模块和数据采集模块。介绍了控制系统软件的总体流程,完成了控制系统嵌入式软件及其上位机监控软件的设计。实验结果表明,所设计的控制系统应用于巡检机器人可以实现对配电房供电设备的自动巡检,从而验证了控制系统的有效性与合理性,具有显著的推广应用价值。  相似文献   
3.
This paper presents an inspection policy to detect failures of a single component system that remain hidden otherwise. Inspection reveals whether the unit is in good or failed state. The possibility of non perfect testing is assumed, thus, successive inspections may fail detecting a failure or result in a false alarm. The occurrence of false alarms is reported in optical fire detectors and inspection of printing circuit boards which are on the basis of electronic systems. A two-phase inspection schedule takes into account the changes in component’s aging. The system may undergo different inspection frequencies to detect both early failures or those due to the natural deterioration in the system as time goes by. The examples reveal the advantages of a two-phase inspection when comparing with the unique interval inspection.  相似文献   
4.
航天立体测绘相机受卫星发射过程的振动、冲击以及复杂的空间环境的影响,相机的靶面将不同程度地偏离相机的焦平面,导致图像分辨率下降.对于测绘相机,其主点位置和主距变化量直接影响地面目标定位准确度.为了弥补利用编码器进行检焦的不足,提出了一种基于像散量的检调焦方法.该方法采用四象限光电探测器测量相机靶面变化引起的像散量,参照已标定的靶面位置与像散量之间的关系,计算出靶面偏离相机焦平面的实际大小和方向.这种检焦方法包含引起相机靶面离焦的所有因素,试验结果表明,基于像散法的测绘相机调焦机构的分辨率可达0.025 mm.  相似文献   
5.
介绍了一种用于玻璃疵病在线检测的近摄工作距成像光学系统,其光组结构形式采用了光阑后置的准远心结构形式,主要光学参量为f′=14 mm;在物像距为250 mm约束条件下,物方视场达到90 mm(对角线);F/number=3.56;光谱适应范围为400~800 nm,对应的空间分辨率为100 lp/mm时,调制传递函数大于0.29.  相似文献   
6.
An inspection game models a conflict situation between an inspector and an inspectee. The mathematical analysis aims to generate optimal behavior of the inspectee under the assumption that an undesirable action of the inspectee could otherwise be carried out strategically. In this paper the controller’s (inspector’s) particular job is to audit a manager’s (inspectee’s) decision and to submit a report to the company’s top managers for examination. Thus, a conflict as regards the choice of behavioral actions of the manager, the controller and the top management impends. Based on Fandel and Trockel (2011a) this modified inspection game is discussed here for the first time as a three-person game in the context of a manager’s faulty decision that will unnecessarily add to the company’s costs and that the top management understandably wishes to minimize. We will first examine the conditions under which a Nash equilibrium occurs in this three-person game in which poor management, poor monitoring and poor revision coincide. We will then examine the effects that the penalties and bonuses exert on the Nash equilibrium solution. We will find that penalties and bonuses can neutralize each other in their effects on the improved decision making by the manager and the controller.  相似文献   
7.
采用红外图像系统对收集到的针式、激光、喷墨3种类型打印机的打印字迹样本各4份分别进行检验,依据3类打印机打印字迹的可见图像、化学图像和红外谱图,可以鉴别3种类型的打印机。可见图像鉴别可根据字迹的清晰程度及有无虚边等特点加以鉴别,化学图像鉴别可根据在不同的波程范围上化学图像清晰程度不同为依据。红外谱图部分主要是在相同的波程上吸收峰数目不同作为鉴别的主要依据。通过红外图像法鉴别打印机种类与其他方法相比,具有不破坏检材、检测范围广、检测速度快等优点。  相似文献   
8.
We consider a deteriorating system submitted to external and internal failures, whose deterioration level is known by means of inspections. There are two types of repairs: minimal and perfect, depending on the deterioration level, each one following a different phase-type distribution. The failures and the inspections follow different Markovian arrival processes (MAP). Under these assumptions, the system is governed by a generalized Markov process, whose state space and generator are constructed. This general model includes the phase-type renewal process as a special case. The distribution of the number of minimal and perfect repairs between two inspections are determined. A numerical application optimizing costs is performed, and different particular cases of the model are compared.  相似文献   
9.
A warm standby n-system with operational and repair times following phase-type distributions is considered. The online unit goes through degradating levels, determined by inspections. Two types of repairs are performed, preventive and corrective, depending on the degradation level. The standby units undergo corrective repair. This systems is governed by a level-dependent-quasi-birth-and-death proces (LDQBD process), whose generator is constructed. The availability, rate of occurrence of failures, and other quantities of interest are calculated. A numerical example including an optimization problem and illustrating the calculations is presented. This system extend other previously studied in the literature.  相似文献   
10.
The revision of ISO/IEC Guide 43 is well underway by CASCO Working Group 28, with the author as Convener. The ballot on the committee draft was successfully completed in June 2008. The Working Group met in September to resolve the CD comments and to recommend that the document should advance as an ISO/IEC DIS. The document is in harmony with ISO/IEC 17025 (2005), ILAC G13 (2007), and the IUPAC Harmonized Protocol (2006) for proficiency testing. Major changes from Guide 43 include considerations for inspection bodies, requirements for metrological traceability of assigned values for calibration schemes, limitations on subcontracting, requirements for reporting the uncertainty of assigned values, and for including method information and technical commentary in scheme reports. Minor changes include requirements for equipment used in the manufacture and testing of proficiency test items, considerations for handling laboratories’ reported uncertainties, and the issuance of certificates of participation. These changes have not generated any substantial objections from the CASCO membership and liaisons.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号