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91.
在目前的网络舆情事件传播分析中,尽管生命周期模型能够较好地描述舆情事件的发展规律,但却忽略了部分时期之间存在的共性特征,无法充分体现意见领袖对网络舆情事件传播过程的影响。本文提出了一种基于知识图谱和二级传播理论的网络舆情事件传播分析方法,首先,构建网络舆情事件知识图谱;然后,基于知识图谱计算用户影响力挖掘意见领袖;最后,考虑到意见领袖的重要地位,为有效刻画网络舆情传播规律、周期与途径,根据传播学二级传播理论构建网络舆情事件传播模型,将生命周期模型的五个时期按照舆情发展态势划分为三个阶段:潜伏期(爆发期阶段)、爆发期(成熟期阶段)以及成熟期和衰退期(消亡期阶段)。实验结果表明,该方法能够有效计算和发掘包括意见领袖在内的用户影响力,传播、分析网络舆情事件效果较好。  相似文献   
92.
文章以《史记》实录精神与托愤精神组合为突破口,阐述了实录精神、托愤精神的远源和在史文中的凸显,进一步挖掘二者之间相悖的二元性关系,从而揭示《史记》中所蕴含的这种文化悖论本身的深刻性、美感魅力以及难解的文化之谜。  相似文献   
93.
为了提高低功率霍尔推力器放电通道内中性原子分布均匀性,采用有限元方法对阳极供气环关键结构参数进行优化研究。针对双腔式阳极供气环结构,重点分析了缓冲腔容积比以及缓冲腔隔板导流小孔数量等关键参数对阳极供气均匀性的影响。研究结果表明:随着缓冲腔容积比的增大,阳极供气环出气孔差异率先快速减小后趋于稳定,其中当容积率k=1.0时,平均差异率和最大差异率分别为1.77%和3.79%;隔板间导流小孔数量从8增加到14时,出气孔差异率呈现浴盆曲线特性,其中导流孔数量为10时,平均差异率和最大差异率分别为1.8%和3.8%。研究结果可为霍尔推力器阳极供气环工程设计提供理论支撑。  相似文献   
94.
针对火箭炮武器系统对集群目标射击中重复毁伤概率无法求解的问题,基于火炮射击理论和毁伤理论,建立了火箭炮对集群目标射击时重复毁伤概率模型,基于像素法和矩阵法对作战想定中的重复毁伤问题进行了仿真,并与模型所得理论计算结果进行了对比分析。仿真结果表明:重复毁伤模型具有较高的精度,适用于火箭炮武器系统对集群目标射击中有效毁伤效率的校正和重复毁伤概率的求解。  相似文献   
95.
基于二维微幅波理论,采用特征函数展开和匹配渐进法建立了气浮箱型结构纵荡运动的解析解,将Matlab程序计算结果与MOSES数值模拟结果进行了对比分析,验证了程序的合理性;进而对不同吃水、不同水深下结构纵荡运动的附加质量系数和阻尼系数的幅频变化规律进行了研究。结果表明:由于未考虑结构内部气体的可压缩性,数值模拟结果大于程序计算结果,MOSES计算结果偏安全;在一定频率区段上,吃水的增加对结构附加质量系数和阻尼系数有显著影响;随着水深吃水比的增加,结构的附加质量系数和阻尼系数呈增大趋势,只有在圆频率为0.65~0.9 rad/s时呈减小趋势,而阻尼系数则呈增大趋势。  相似文献   
96.
This article examines the arms control logic that was applied to the only regional arms control talks that have taken place in the Middle East to date: the Arms Control and Regional Security (ACRS) working group that was part of the multilateral track of the Madrid peace process in the early 1990s. It highlights both the successes and major constraints of the ACRS talks in an effort to assess what might be relevant to the weapons of mass destruction-free zone conference proposed for later this year. In addition to the basic arms control dilemmas that will continue to challenge this conference—as they did ACRS—the article suggests that current conditions in the Middle East are even less conducive to regional dialogue than they were in the earlier period, due to the internal upheavals in several key Arab states, and the specific challenge of Iran's move to develop a military nuclear capability.  相似文献   
97.
This article reviews the origins and evolution of the Middle East weapons of mass destruction-free zone (WMDFZ) concept and the proposal for a 2012 conference on the subject, and explores new challenges and opportunities for regional arms control in the current regional environment. It suggests that new models may be necessary to revitalize regional arms control efforts. The establishment of a broad regional security forum could include, but should not be limited to, curtailing weapons of mass destruction through the zone approach. Even if the 2012 conference fails to materialize, or is limited to a one-time event, the proposal for such a conference has provided an important opportunity to rethink future options for a regional arms control and security process.  相似文献   
98.
ABSTRACT

The threat of terrorist use of weapons of mass destruction remains a daunting concern. Governments have undertaken several initiatives at the national and international level to prevent such illicit use, yet challenges remain. Notable is the absence of a single collaborative international forum of experts dedicated solely to bioterrorism prevention. The establishment of a Bioterrorism Prevention Initiative could be a possible solution to address this gap. This article explores possibilities for such an initiative and the ways in which it could strengthen the existing bio-nonproliferation regime.  相似文献   
99.
The Constitutive Act of the African Union (AU) provides for the right of the continental body to intervene in the face of war crimes, genocide and crimes against humanity. According to its formulation, Article 4(h) intervention entails military force, which is triggered when a target state fails to discharge its duty to protect its population from mass atrocities. Although Article 4(h) is an ambitious statutory commitment to intervene in a member state by the AU, the Libyan crisis in 2011 showed the ambivalence of the continental institution to act in a decisive and timely manner. The AU's failure to invoke Article 4(h) exposed the need for building the capacity and political will to intervene and to interpret Article 4(h). Therefore, the primary focus of this article is on how Article 4(h) should be interpreted. Flowing from the Pretoria Principles, which seek to provide clarity on the implementation of the AU's right of intervention, Article 4(h) should be viewed as a duty rather than a right to prevent or stop mass atrocities. The duty dimension of Article 4(h) derives from the international instruments that AU member states have ratified to prevent mass atrocities. Rather than being a paper tiger, Article 4(h) should be used in a proactive and timely manner as a military option available to the AU to persuade member states to prevent or halt atrocities. As a last resort, military force pursuant to Article 4(h) should aim at protecting the population at risk and pursuing the perpetrators in order to avoid contravening Article 2(4) of the Charter of the United Nations (UN). Although military intervention can save lives in the short term, it cannot necessarily address the underlying, structural causes of atrocities, such as ethnic rivalries, economic inequalities and scramble for natural resources, among others. Therefore, the prevention of mass atrocities should not be equated with, or be seen through the prism of, Article 4(h) intervention alone. The focus should instead be on the entire spectrum of preventive strategies at the disposal of the AU in the face of mass atrocities, including the African human rights system and the African Peer Review Mechanism.  相似文献   
100.
油罐是油品储运的重要设备,罐底最易出现穿孔渗漏油现象,致使罐基内部油气质量分数高于正常值。以油库中柴油覆土罐群为例,研究并试验了根据罐基油气质量分数识别罐底渗漏的方法:分析罐基探漏孔位置分布并钻孔;多次探测罐基油气质量分数,根据探测数据识别各罐有无底部渗漏;为了便于以后检测油库时识别各罐有无渗漏,为各罐建立状态监测表,并将无渗漏的罐基油气质量分数最高值暂定为该类罐的安全值,低于该安全值的油罐可直接判定为无渗漏。实践结果证明,这种不开罐检测罐底渗漏油的方法可及时发现故障并采取措施,对储油安全具有重要意义。  相似文献   
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