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1.
王韬是早期办报国人中卓有成就的一位,本文从新闻自由、报刊功能、办报目的、报刊人才选用四个方面论述了他的新闻思想,这些思想对于近代中国报刊思想体系的初步形成具有重要的意义.  相似文献   

2.
英文报刊选读是英语专业教学大纲规定的课程之一,其目的在于培养学生阅读英语报刊的能力,提升学生的英语综合运用水平。面临当今教学中的诸多问题,翻转课堂这一新型的教学方式为改善英文报刊选读教学开创了新思路。本文通过分析英文报刊选读课程的研究现状和教学问题,提出英文报刊选读课程实施翻转课堂的原则,尝试构建翻转课堂教学模式并分析实例,探索该课程教改的主要方向和措施。  相似文献   

3.
长征系列运载火箭发射人造卫星的情况简析   总被引:2,自引:1,他引:1  
分析了现在报刊上有关长征系列运载火箭发射情况报道中存在的问题,给出了1970~1998年长征系列运载火箭发射人造卫星情况的汇总表。  相似文献   

4.
分析了现在报刊上有关长征系列运载火箭发射情况报道中存在的问题,给出了1970 ̄1998年长征系列运载火箭发射人造卫星情况的汇总表。  相似文献   

5.
2月10日,受中国宇航学会委托,北京卫星环境工程研究所组织了与国家新闻出版总署新闻报刊司的交流活动.交流会由中国宇航学会副秘书长龚金玉主持,国家新闻  相似文献   

6.
针对目前在报刊、资料中大量出现的“分贝(dB)”及其相关符号使用比较混乱的状况和其与GB3100~3102-1993《量和单位》中的规定有相互矛盾之处,通过广泛查证,深入研究有关国家标准后,提出了规范使用“分贝(dB)”单位的建议。  相似文献   

7.
近年来国外报刊经常提到美国的(或里根的)“星球大战”计划,有的甚至把它和曼哈顿计划或阿波罗登月计划相提井论。美国总统里根最近还多次声明,在同苏联进行裁军谈判中,美国决不放弃“星球大战”计划。本文主要根据美国官方材料,对该计划作一概括介绍。  相似文献   

8.
网络信息技术的快速发展,为高校思想政治工作提供了新的手段,极大地拓展了思想政治工作的空间和渠道。思想政治教育工作者有必要深入研究学生思想活动的新情况、新特点,充分发挥网络信息技术的优势,创新思想政治工作的方法、形式和手段,进而完善高校思想政治工作体制。  相似文献   

9.
高校思想政治理论课是高校思想政治教育的主渠道、主阵地,如何增强高校思想政治理论课教育的实效性、长效性已成为高校思想政治教育研究的重要课题.论文认为,着眼于长效机制的构建,必须建立领导重视的保证制度,树立以人为本的教学理念,拥有稳定而高素质的人力资源,积极推进课程建设与教学创新.  相似文献   

10.
为了了解我校大学生的思想政治状况,切实加强和改进我校大学生思想政治教育,为我校的思想政治工作提供依据,我们近期以问卷调查的方式对我校一、二、三年级的部分学生进行了思想政治现状方面的调查,调查表明,我校大学生的思想政治状况总的来说是好的,但还有一些不够完善的方面,文章对此作了初步的分析和探讨。  相似文献   

11.
姜文权 《火箭推进》2004,30(6):42-46
从工艺方案和模具设计原则等方面探讨了冷挤压工艺应用于阀芯生产的原理与优势,介绍了一种典型阀芯的冷挤压工艺试验结果。试验证明采用冷挤压成型工艺能够解决影响阀芯密封性和产品质量稳定性的塑料与金属脱离等问题。  相似文献   

12.
采用普通液压机和新型高效的模压半炭化成型工艺,在大气环境下制备出了高密度、低成本的焦炭颗粒增强沥青基炭复合材料.研究了模压压力对焦炭颗粒增强沥青基炭复合材料的体积密度和抗压强度的影响趋势,并探讨了复合材料的体积密度与抗压强度之间的相互关系.结果表明,增大模压压力,沥青基炭复合材料的体积密度和抗压强度随之明显增加;继续增大模压压力,体积密度仍然呈上升趋势,但抗压强度却突然下降;沥青基炭复合材料的体积密度越高,其抗压强度未必也就越大.  相似文献   

13.
在压紧机构压紧力以及发射阶段加速度工况载荷共同作用下,收拢压紧状态的柔性折叠式太阳翼的太阳电池板上电池片的应力应满足力学强度要求。文章采用有限元方法对电池片应力主要影响因素,包括聚酰亚胺泡沫布局和厚度、聚酰亚胺泡沫力学性能、盖板结构及埋件形状等进行计算分析;总结降低收拢压紧状态下柔性太阳翼压紧点附近电池片压应力的主要来源途径,为柔性折叠式太阳翼的工程研制提供设计分析思路。  相似文献   

14.
A pressing issue facing the US space program is the projected shortfall in the skilled aerospace workforce, as the number of students in space-related fields wanes. This has prompted many to emphasize the rhetoric of inspiration that prevailed during the Cold War, at the expense of concrete arguments for space that are thought to be lackluster and insufficient. This essay argues that the logic of inspiration fails to consider the changed context and attitudes of this younger public. Instead, such an approach proves counterproductive in attracting generations compelled by a host of ideas, some incompatible with the rhetoric of competition and prestige that prevailed before. Arguments that draw attention to the pragmatic elements of space, and that successfully align space with the notions that make sense now, may in turn prove to be the solution to draw the best and the brightest to the space program.  相似文献   

15.
美国对军事航天器的依赖性不断增强,也面临着航天器越来越长的研制周期和越来越高的研制成本,因此,改变军事航天器的发展策略成为当务之急。美国为提升战场实战能力正在进行发展思路的战略性调整,主要包括:拓展搭载军事有效载荷的途径;推进将大型卫星有效载荷拆分成小卫星的模式;开发分布式军事太空系统结构;对运载资源挖潜;优化商业模式实现业务拓展。对已有卫星的后续系统,进行规模改造与能力提升途径的调整,主要包括:对于军事通信卫星,扩大宽带或"超高频"(SHF)系统,突出窄带或"特高频"(UHF)系统及"先进极高频"(AEHF)系统;分步升级GPS的地面部分,将GPS-3提升为国家关键基础设施;确保导弹预警卫星系统重点。在开发新系统时,美国注重提高效能和降低成本,发展有效的支持能力和低成本小卫星系统,提高低成本机动发射和快速进入太空的能力,并以轨道资源利用为目的开拓新途径。  相似文献   

16.
针对活门盘的结构特点和密封要求,全面分析了活门盘的密封机理,得出活门盘密封比压应大于活门所需密封比压,给出了计算公式,并进行了活门盘热压工艺研究。采用该工艺压制的活门盘密封比压满足理论要求,产品通过了试验验证,满足设计要求,并通过了飞行试验考核。  相似文献   

17.
Two problems in studying deep space are discussed that are, in the author's opinion, the most important. The first is soil sampling from the smaller bodies of the Solar System, such as the Martian satellite Phobos and asteroids of groups C and S of the Main Asteroid Belt. This soil (so-called primordial substance) can help to elucidate some problems of the Solar System's formation; in particular, to construct a reliable model of the internal structure of the Earth. The second problem is to reveal all sufficiently large asteroids penetrating inside the Earth's orbit and to catalog those asteroids that are hazardous from the viewpoint of collision with the Earth. To this end, it is suggested to launch five or six Earth-orbiting spacecraft with telescopes capable of recording objects down to a brightness of 22– 25 m . It is pointed out that both problems can be solved in the near future using comparatively cheap standardized space vehicles launched into near-Earth orbits by the Soyuz carrier rocket and boosted further by electro-jet engines of small thrust.  相似文献   

18.
《Acta Astronautica》2007,60(12):1160-1162
It may be hoped that an initial discovery of extraterrestrial life and its disclosure will be done by accident. An event of that kind would have its own dynamic, and while communications about the discovery might be strained at times, there would be less likelihood that lines of inquiry and discourse would have already been taken by the participants and the press. In an ideal world (or worlds), the discovery would come ready-made with a picture or pictures that would be useful as an immediate verification of its reality. But such is not the way of the real world (or worlds, apparently). Lessons learned from the publication of the ALH84001 results in Science magazine are indicative of what may be a more likely scenario. Nonetheless, even that publication was held in confidence for much of the time leading up to NASA's press conference, and the science team doing the work was accordingly insulated from press inquiry while the work was underway. Envisioning a Mars sample return mission, or other, similar sort of endeavor that may involve a dedicated team of scientists—working under continual public scrutiny—it is clear that the circumstances that surround any fundamental discovery about life in the sample would be quite different. Planning for a communications strategy to support the operations of a Mars sample receiving facility (or facilities) must take those circumstances into account. An optimization of the time spent communicating the results of the facility's work should acknowledge the time and effort required, and make provisions for the work to proceed without extensive interruptions—and without being influenced by the expectations of the press or the public. This paper will discuss some of the initial planning associated with the communications strategy surrounding such a facility.  相似文献   

19.
J.D. Rummel  M.S. Race   《Acta Astronautica》2006,59(12):1160-1162
It may be hoped that an initial discovery of extraterrestrial life and its disclosure will be done by accident. An event of that kind would have its own dynamic, and while communications about the discovery might be strained at times, there would be less likelihood that lines of inquiry and discourse would have already been taken by the participants and the press. In an ideal world (or worlds), the discovery would come ready-made with a picture or pictures that would be useful as an immediate verification of its reality. But such is not the way of the real world (or worlds, apparently). Lessons learned from the publication of the ALH84001 results in Science magazine are indicative of what may be a more likely scenario. Nonetheless, even that publication was held in confidence for much of the time leading up to NASA's press conference, and the science team doing the work was accordingly insulated from press inquiry while the work was underway. Envisioning a Mars sample return mission, or other, similar sort of endeavor that may involve a dedicated team of scientists—working under continual public scrutiny—it is clear that the circumstances that surround any fundamental discovery about life in the sample would be quite different. Planning for a communications strategy to support the operations of a Mars sample receiving facility (or facilities) must take those circumstances into account. An optimization of the time spent communicating the results of the facility's work should acknowledge the time and effort required, and make provisions for the work to proceed without extensive interruptions—and without being influenced by the expectations of the press or the public. This paper will discuss some of the initial planning associated with the communications strategy surrounding such a facility.  相似文献   

20.
根据工作中遇到的重型模具在油压机上装卸作业问题,设计了新的作业流程方案及其具体的实施措施,详细地介绍了流程实施过程中所使用工装的结构设计方案。  相似文献   

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