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221.
与传统课堂教学相比,网络教学环境独有的特点对学习者提出了更高的要求:要求学习者不仅要掌握知识、技能,更要学会学习,管理自己的能力,进行有意义、高效的学习,使其努力指向目标并最终实现目标。本文结合师范生公共必修课《现代教育技术》在线网络课程的教学实践,有效跟踪学习者的学习行为活动,分析学习者的学习状态、学习风格,以及对学习行为的自我调节能力,总结摸索出一些培养并提高学习者自我调节能力的指导性策略,希望能对广大网络学习者有一定的借鉴意义。  相似文献   
222.
The sectoral production function model of Feder (1983) has been widely used to examine the link between defence spending and economic growth. In this paper, the model, for which too much has been claimed in some past work, is examined, and the case is made for using growth in real non‐defence output rather than growth in real aggregate output (inclusive of military spending) as the dependent variable. Attention is restricted to a small group of OECD countries for which reliable labour force and capital stock (as well as defence) data are obtainable. With non‐defence output as the dependent variable and using only high quality data, no evidence in favour of the underconsumptionist (as opposed to the defence as a burden) position is found.  相似文献   
223.
In April 2012 a number of former rebels who had been integrated into the Forces Armées de la République Démocratique du Congo (FARDC) mutinied and formed the Movement of March 23, better know as the M23 rebel group. The International Conference on the Great Lakes Region (ICGLR) has been mediating between Kinshasa and the M23 rebel group since 2012, without much success. In August 2013, the Southern African Development Community (SADC) issued a communiqué after its 33rd Summit of Heads of State and Government, stating that while it commends the ICGLR efforts, the talks have become protracted and a deadline needs to be set. The summit also called for an urgent joint ICGLR–SADC summit to address the crisis in the eastern Democratic Republic of Congo (DRC). In addition to this development, the chair of the ICGLR is to be rotated in December 2013, when President José Eduardo Dos Santos of Angola replaces President Yoweri Museveni of Uganda. To date, the mediation has been headed by Uganda and this has raised concerns over the credibility of the ICGLR-led process, since Uganda has been accused of supporting the M23 rebellion in a report released in November 2012 by the United Nations Group of Experts on the DRC. One could question whether the Angolan leadership will bring anything new that could have an impact on the crisis. Many expect that the perceived neutrality that Dos Santos could bring to the negotiations may be a positive step towards reviving the talks that have all but stalled at this point. Another issue of interest is whether the joint ICGLR–SADC summit could instil new life into the mediation process.  相似文献   
224.
BUSTING OUT     
This report explores Iranian popular opinion on the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the determinants of Iranian attitudes. Using data from a 2008 survey of 710 Iranians administered by the University of Maryland's Program on International Policy Attitudes, we find that that a significant minority of Iranians (10 percent in 2006 and 14 percent in 2008) would prefer that Iran withdraw from the NPT. Our statistical analysis shows that Iranians who fear a US attack on Iranian nuclear facilities and distrust the International Atomic Energy Agency are more likely to want to quit the NPT. We therefore argue that those who do not trust other nations are most likely to oppose the NPT.  相似文献   
225.
Abstract

The war on al-Qaeda and its affiliates appears to be endless but every war must end. Winding down the conflicts in Afghanistan and Iraq has been difficult, but both were embedded in what was then called the ‘war on terrorism.’ What does ‘success’ in that war mean? With the death of bin Laden and the increase in drone operations, how far is the US from achieving it? Can this war end? The article analyzes the ongoing US response to the 9/11 attacks in historical context, revealing four patterns common to all prolonged wars: means become ends, tactics become strategy, boundaries are blurred, and the search for a perfect peace replaces reality. It concludes by laying out an effective strategy for ending the war.  相似文献   
226.
红外目标分割方法研究   总被引:2,自引:1,他引:1       下载免费PDF全文
红外目标分割算法对红外目标检测、跟踪具有非常重要的价值。本文利用背景和目标灰度特征,提出一种实现红外目标有效分割的方法,克服红外目标内部温度不稳定造成的误分割问题。本文方法首先采用基于灰度-显著度最大相关准则的二维直方图分割算法进行图像分割;然后,在分割后二值图上进行基于随机种子点选取的区域增长,提取背景;最后,采用形态学方法优化分割结果。相对传统的红外目标检测算法,这种算法具有更好的抗干扰能力,更强的鲁棒性。不仅可以应用于红外图像的目标分割,而且可以应用于其他类似的目标分割问题。  相似文献   
227.
基于状态的维修及其决策模型研究   总被引:2,自引:0,他引:2  
在分析各种传统维修方式优缺点的基础上,研究了基于状态的维修(Condition Based Maintenance,CBM)中现行的几个技术标准IEEE Std 1451、IEEE Std 1232和ISO 13373-1,并着重分析了CBM开放系统体系结构OSA-CBM的7大组成模块,指出了未来CBM的发展应集中于OSA-CBM的第5、6模块的研究。针对这2个模块,给出了一种利用建立数学模型进行装备健康预测及维修决策支持的可行的研究思路和结构框架。  相似文献   
228.
海上机动目标打击效果评估决策支持系统设计   总被引:3,自引:0,他引:3  
针对海上机动目标打击效果评估的特点,运用遥感技术、人工智能技术和模糊评判的方法探索打击效果评估问题。提出一种基于高分辨率遥感图像的打击效果评估决策支持系统,融合人定性分析和机器定量分析的优点,核心是问题处理系统综合运用处理后的遥感信息和支持系统的模型、知识以及数据来评估打击效果,评估模型为二级综合评判模型。对尚处于理论研究阶段的海上机动目标打击效果评估问题有积极的参考意义。  相似文献   
229.
公安现役部队是列入武警序列由公安部门管理的部队。对其执法能力的要求具有特殊性。公安现役院校担负着为公安现役部队培养人才的任务,教学过程中应对公安现役部队执法能力的涵义、执法能力的内容和因执法能力不足而产生的问题以及解决问题的途径作了探讨。提出创新法学教学模式是提高公安现役部队执法能力的有效方法。  相似文献   
230.
African states' attendance at and participation in the preparations for the 2015 Review Conference of the Parties to the Treaty on the Non-proliferation of Nuclear Weapons (NPT) has produced mixed results, with the continent acting as both agent and bystander in respect of certain issues. African agency is evident in, for example, its position as a member of groupings on Iran's nuclear weapons programme and the Middle East Nuclear Weapons Free Zone. Less agency is evident in states' individual actions. This underscores the importance of African states' preference for multilateralism. However, African agency is also less evident in African multilateral efforts at the NPT preparatory meetings. The impact of these developments on the 2015 NPT Review Conference is too soon to tell but may bode ill for African agency.  相似文献   
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