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721.
现代教学原则是教师进行教学活动所应遵循的准则。从多媒体电子教案的教学内容选择、多媒体电子教案的演示设计与运用,以及多媒体教学中的教师主导作用和课堂交流3个方面,探讨了如何在多媒体教学中贯彻现代高等学校的教学原则,以充分发挥多媒体教学的优势、弥补其不足,提高课堂教学效果。  相似文献   
722.
机器学习是通过数据训练使机器获取新的知识和技能的计算机技术,是人工智能技术的核心和前沿领域之一。本文以Web of Science?核心合集收录的机器学习领域相关SCI论文和incoPat全球专利数据库收录的机器学习领域相关专利为数据源,运用科学计量方法对文献数据和专利数据进行时间、地域和机构分布分析,展示了机器学习领域研究实力的分布情况,并对机器学习的发展趋势进行了分析;然后利用主题聚类分析方法及可视化软件VOSviewer,挖掘出机器学习领域的关键技术、技术热点;最后对结果进行了总结分析,以期为我国机器学习发展布局提供参考和借鉴。  相似文献   
723.
What organisational attributes enhance a military’s ability to effectively adapt on the battlefield? Upon the outbreak of war in July 2014 between Israel and the Palestinian militant group Hamas, the Israel Defense Forces (IDF) encountered an expansive network of tunnels from which Hamas was launching large-scale assaults into Israel. This article illustrates that the IDF’s ability to successfully adapt ‘under fire’ to this battlefield surprise was facilitated by several important attributes related to its organisational learning capacity: a dynamic, action-oriented organisational culture, a flexible leadership and command style, specialised commando units which acted as ‘incubators’ for learning and innovation, and a formal system to institutionalise and disseminate lessons learned.  相似文献   
724.
随着全球导航卫星系统的广泛应用,其安全性问题也逐渐成为人们关注的焦点。为了对目前最具隐蔽性的诱导式欺骗技术进行检测,提出一种对两路导航信号同时进行处理的combo-signal模型,并提出基于这种信号处理模型来对诱导式欺骗信号进行检测的方法;分析了该方法的检测门限;采用北斗的B1I 和B1C信号在实现了combo-signal处理模型的软件接收机上对该检测方法进行了验证,实验结果证明该方法可以有效地对诱导式欺骗进行检测,统计得到的检测概率跟前面的分析结果一致。  相似文献   
725.
针对失控翻滚目标任意位置悬停的控制问题进行研究。在目标器轨道坐标系下建立任意偏心率的三维相对运动方程,并分析失控翻滚目标的姿态运动特性。将悬停问题解耦为三个通道的二维模糊控制问题,并以x通道为例进行Mamdani型模糊控制器设计。确定相应的模糊子集、隶属度函数以及模糊控制规则表,采用面积中心法解模糊化。通过数值仿真验证了模糊控制器的控制性能。  相似文献   
726.
Tom Dyson 《Defence Studies》2019,19(2):107-129
The post-Cold War era has witnessed the rapid expansion of organisational learning initiatives within NATO militaries, especially formal “lessons-learned” processes. The effectiveness of national lessons-learned processes in recalibrating military activity to the demands of ongoing operations has been highly-differentiated. However, the academic literature on military change and practitioner guidance has been slow to investigate the key features of best-practice in military learning. This article breaks new ground by drawing upon the literature on dynamic organisational capabilities to explore the fundamental organisational processes and activities which are necessary to implement successful lessons-learned. It examines, in particular, the organisational features which facilitate “knowledge transformation”: the effective combination of new knowledge gained from intra- and inter-organisational learning with existing organisational knowledge. The article concludes by highlighting several potential future empirical and theoretical research agendas in military learning and the importance of engagement between lessons-learned practitioners and organisational learning scholars.  相似文献   
727.
We present, analyze, and compare three random search methods for solving stochastic optimization problems with uncountable feasible regions. Our adaptive search with resampling (ASR) approach is a framework for designing provably convergent algorithms that are adaptive and may consequently involve local search. The deterministic and stochastic shrinking ball (DSB and SSB) approaches are also convergent, but they are based on pure random search with the only difference being the estimator of the optimal solution [the DSB method was originally proposed and analyzed by Baumert and Smith]. The three methods use different techniques to reduce the effects of noise in the estimated objective function values. Our ASR method achieves this goal through resampling of already sampled points, whereas the DSB and SSB approaches address it by averaging observations in balls that shrink with time. We present conditions under which the three methods are convergent, both in probability and almost surely, and provide a limited computational study aimed at comparing the methods. Although further investigation is needed, our numerical results suggest that the ASR approach is promising, especially for difficult problems where the probability of identifying good solutions using pure random search is small. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
728.
Covering models assume that a point is covered if it is within a certain distance from a facility and not covered beyond that distance. In gradual cover models it is assumed that a point is fully covered within a given distance from a facility, then cover gradually declines, and the point is not covered beyond a larger distance. Gradual cover models address the discontinuity in cover which may not be the correct approach in many situations. In the stochastic gradual cover model presented in this article it is assumed that the short and long distances employed in gradual cover models are random variables. This refinement of gradual cover models provides yet a more realistic depiction of actual behavior in many situations. The maximal cover model based on the new concept is analyzed and the single facility location cover problem in the plane is solved. Computational results illustrating the effectiveness of the solution procedures are presented. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
729.
本文分析了英汉拟声词的语音关系和英语拟声词的语音修辞功能。在保留英语拟声词语音修辞效果前提下,分别从英汉拟声词的语音关系和英汉拟声词的声音发出者所承载的不同文化意象等角度探讨了相应的翻译方法。  相似文献   
730.
任职教育是武警警官再学习的过程。图书馆要根据培训对象的流动性、培训类型的多样性、培训内容的需求性和培训方式的开放性等任职教育特点,在提高信息服务功能上、在树立“以人为本”的理念上、在开展个性化服务上下功夫。  相似文献   
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