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241.
《防务技术》2020,16(2):392-400
The optocoupler is a weak link in the inertial navigation platform of a kind of guided munitions. It is necessary to use accelerated storage test to verify the storage life of long storage products. Especially for small sample products, it is very important to obtain prior information for the design and implementation of accelerated degradation test. In this paper, the optocoupler failure mechanism verification test is designed and the experimental results are analyzed and the prior information is obtained. The results show that optocouplers have two failure modes, one is sudden failure and the other is degradation failure; the maximum temperature stress of optocoupler can't exceed 140 °C; the increase of leakage current of optocoupler is caused by movable ions contaminating the LED chip. The surface leakage current is proportional to the adsorption amount. The increase of leakage current makes p-n junction tunneling effect occur which LEDs the failure of the optocoupler. The lifetime distribution model of the optocoupler is determined by the failure physics. The lifetime of the optocoupler is subject to the lognormal distribution. The degeneracy orbit of the optocoupler leakage current is described by a power law model. The estimated values of the orbital parameters are initially calculated and the parameters of its life distribution function are deduced. The above information lays a good foundation for the optimization design and data processing of the accelerated degradation experiment. 相似文献
242.
信息与通信技术是影响国家政治、经济和军事等重要领域的高精尖技术。本文认为,美国政府通过启动"301调查"和建立出口管制实体清单等多种方式对中国信息与通信领域实施技术封锁和产品禁运,将延缓中国信息与通信技术的发展进度,加大全球信息与通信技术产业发展的成本消耗,但同时也刺激并加快了中国信息与通信技术自主可控的转型步伐。据此,本文提出加强顶层设计和统筹谋划、营造自主可控的产业生态环境、加强专业化人才队伍培养、构建合作共赢的命运共同体,努力突破信息与通信技术封锁等几项措施,以期为我国信息与通信技术领域的发展提供一定的借鉴意义。 相似文献
243.
Sandor Fabian 《Defense & Security Analysis》2019,35(3):308-325
Following Russia’s annexation of Crimea and its initial actions in eastern Ukraine in 2014, the term hybrid warfare has received much public attention. Many have argued that the Russian actions we saw in Ukraine were part of a completely new strategy while others have suggested that there was nothing new in Russia’s actions. This article takes a critical look at these claims. Through the assessment of the history of the term hybrid warfare and a rigorous analysis of the so-called Gerasimov doctrine, this study finds that the Russian hybrid warfare strategy is rather a western myth than a formal comprehensive Russian strategic concept. Additionally, through the assessment of the Russian use of information operations and the way she has utilised the cyberspace in several recent conflicts, the study finds that against all claims Russia did not make these areas its main battlefield, but rather has been using them in support of its traditional concepts. 相似文献
244.
Reliability data obtained from life tests and degradation tests have been extensively used for purposes such as estimating product reliability and predicting warranty costs. When there is more than one candidate model, an important task is to discriminate between the models. In the literature, the model discrimination was often treated as a hypothesis test and a pairwise model discrimination procedure was carried out. Because the null distribution of the test statistic is unavailable in most cases, the large sample approximation and the bootstrap were frequently used to find the acceptance region of the test. Although these two methods are asymptotically accurate, their performance in terms of size and power is not satisfactory in small sample size. To enhance the small‐sample performance, we propose a new method to approximate the null distribution, which builds on the idea of generalized pivots. Conventionally, the generalized pivots were often used for interval estimation of a certain parameter or function of parameters in presence of nuisance parameters. In this study, we further extend the idea of generalized pivots to find the acceptance region of the model discrimination test. Through extensive simulations, we show that the proposed method performs better than the existing methods in discriminating between two lifetime distributions or two degradation models over a wide range of sample sizes. Two real examples are used to illustrate the proposed methods. 相似文献
245.
246.
CSCW技术在装备远程维修支持信息系统中的应用 总被引:1,自引:0,他引:1
CSCW技术的应用领域非常广泛,就CSCW的系统模型、体系结构进行了探讨,并在此基础上对CSCW技术在装备远程维修支持信息系统中的应用进行了研究。 相似文献
247.
248.
刘洁 《中国人民武装警察部队学院学报》2010,26(1):91-93
信息技术与课程整合是一个长期的过程,在此过程中,需要根据外在条件和内在主体的不断变化,适时调整整合的内容和步骤以及相关的策略。在设计信息技术与课程整合时,应该重视诸多不确定性带来的复杂性,保证这一系统的开放性和动态性。踏踏实实地对待信息技术与课程整合这一长期任务。 相似文献
249.
孙粤文 《中国人民武装警察部队学院学报》2003,19(4):55-57
江泽民现代化思想是在新的历史条件下对邓小平现代化思想的继承、丰富和发展。本文从思想动力、发展道路、目标内涵、实现方式和根本保证五个方面来论述江泽民的现代化思想。 相似文献
250.
“基于Web技术管理信息系统”是将Web技术与数据库技术相结合,从而实现动态信息管理的系统。提出了“基于Web技术的固定资产管理系统”的解换方案,进行了系统分析,详述了系统的功能,并对关键技术的实现方法进行了论述。该系统对于提高固定资产管理正规化、现代化、科学化的管理水平有着重要意义。 相似文献