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1.
今天,国防科技工业完成了一次伟大改组,这是件很大的事情,不仅是党的喜事,全国的喜事,人民的喜事,也是国防科技工业的喜事。国防科技工业非常重要,是战略性产业,是国家的基础,也是我国综合国力的体现,没有国防就没有国家,没有国防工业,就没有国防。 要强大,就要有实力,我最近非常高兴,因为我们发射了几次卫星,发一次成一次,每发必中,都打成了,谢谢大家。中国航天战线连续三年15次火箭  相似文献   

2.
近距平行跑道运行技术在上世纪七、八十年代开始被采用,主要在美国和欧洲几家大型机场,当时民用航空市场发展蓬勃,机场为了扩大容量,满足市场需求,不断的征地,改建和新建候机楼、跑道等基础保障设施,但是,随着国家和民众越来越重视对土地资源的利用和保护,使得建设成本大幅增长,因此,机场当局想尽办法在有限的场区范围内,增加跑道的数量,通过设计跑道按照不同的布局,实现跑道容量的最大化,提高机场的运行能力。  相似文献   

3.
阐述了用计算机实现对程控交换机的控制与管理,实现了宾馆饭店长途电话的自动管理,无须操作人员的操作,计算机通过网络,从前台提取客人入店离店的信息,根据程控交换机的状态,自动控制其运行,不影响程控交换机的工作,而实现程控交换机的开门封门,解决了宾馆饭店长途电话跑费问题,杜绝了由于长途电话费用问题,而引起的争执。既提高了办公室自动化程度,又提高了经济效益,减少了人力物力。  相似文献   

4.
在低碳经济的大环境下,物流企业面临很大的困惑,由于物流企业存在管理水平,生产经营方面的问题,普遍物流行业的发展水平不高,物流企业只有在政府的支持下,加强人员素质的培养,引进现在的信息技术,完善行业的标准化,改变经营等情况下才能做到物流企业成本的节约,真正为低碳经济服务.  相似文献   

5.
坚持党的思想路线 ,解放思想、实事求是、与时俱进 ,是我们党坚持先进性和增强创造力的决定性因素 ,也是十六大报告的精髓。在高等教育改革进入新的时期 ,加快发展任务十分繁重的情况下 ,按照自治区党委的部署 ,开展解放思想再讨论 ,在全校形成解放思想、实事求是、与时俱进的良好氛围 ,对于凝聚全校员工的意志和力量 ,巩固和拓展当前的大好形势 ,抓住机遇 ,乘势而上 ,实现我校新的历史性跨越具有重要意义。1 解放思想是发展的前提和基础解放思想 ,就是在马克思主义的指导下 ,打破习惯势力和主观偏见的约束 ,解除束缚人们的精神枷锁 ,把思…  相似文献   

6.
二十多年来,廊坊凭借独特的地理优势,城市建设和经济发展迅速,人们生活水平不断提高,但作为城市软实力之一的文化建设仍显匮乏,对城市精髓的人文精神的挖掘较为滞后,这不利于城市的综合发展,更难以明确清晰的城市文化定位。笔者认为,廊坊人文精神的塑造需要政府决策者的高度认识,需要凝聚统一的价值体系,需要遵循历史面向未来,更需要与社会、经济发展相适应。这样,才能启示人的思想,影响人的行为,引导城市的未来形态。  相似文献   

7.
振动试验作为考察产品可靠性的重要手段,如何正确有效的进行振动试验,是每个实验室或者试验人员必须要掌握的技能,振动试验夹具的优劣性,是保证振动试验顺利进行的重要前提,在实验室模拟振动时,输入量级和输出量级进行1∶1的传递,是不可能的.如果将振动台的激励源、夹具、产品看做三个不同的单元,则振动台的激励源可被视为输入,夹具视为传递,产品视为输出,这三者尽可能的刚性连接,由于阻尼的存在,在量级的传递过程中不可避免的会出现能量损失,导致无法实现1∶1的传递,但可将这种输入和输出之间的传递比尽可能的做到最大,也就是夹具的传递率最大,以这种假设为前提,以系统运动微分方程为理论基础,通过试验时的工作频率与产品及夹具在粘性阻尼系统中固有频率的关系,得出一个关于系统阻尼系数方程,同时借鉴半功率带宽法求的其阻尼系数,从而得到完整的输入与输出的关系比,即为夹具的绝对传递率,这样可以使得试验操作人员在进行试验的同时,更加明确输入的量级与产品实际经受的量级的对比关系,同时为工程中遇到此类问题时,提供一个切实可行的方法.  相似文献   

8.
标准计量处是一个很重要的部门,你们讲是总公司标准化和计量管理的首脑机关,是打基础,开展技术储备,提供技术支持的部门。这项工作又是质量的基础,确实很重要,但又容易被忽视,一年有可能就招呼一、二次,但自己的工作要做好,目标性要强,韧性要强,要夯实这项基础工作。 当前,标准化工作的主要问题,我认为:第一工艺标准落伍,没有完全跟上航天科技工  相似文献   

9.
高等学校实行党委领导下的校长负责制 ,党委是学校的领导核心 ,一个学校搞得好不好 ,党委的领导水平、决策能力起着关键作用。当前 ,我校正处在发展的重要机遇期 ,党委必须站在战略高度 ,总揽学校全局 ,加强对学校工作的领导 ,抓住机遇 ,趁势而上 ,推动我校在新的历史时期实现新的跨越。1 抓党建 ,充分发挥各级党组织的作用加强党的自身建设 ,从严治党 ,是党形成战斗力、凝聚力的根本保证 ,是党实施有效领导的关键。我校党的建设 ,要抓住三个方面 :首先是加强学校党委思想、组织、作风的建设 ,使党委领导班子成为坚强有力的战斗集体。学校…  相似文献   

10.
系统辨识(System Identification)是指根据所测量的系统输入输出离散数据,在给定的某种准则下,确定系统的数学模型,使之最好的逼近所研究系统的动态特性。在控制系统的设计中,如最优控制器设计,控制系统参数综合,以及零极点配置等问题,都是在系统特性已知的前提下才能进行,又如在系统仿真的研究中,也要首先知道被仿真对象的数学模型,但实际上,系统特性往往是未知的,用已知的物理定理进行物理实验来建立模型,往往要遇到很多困难并花费较大代价,这些问题的提出,促进了系统辨识理论和技术的发展。  相似文献   

11.
Horseshoe orbits in the restricted three-body problem have been mostly considered in the Sun–Jupiter system and, in recent years, in the Sun–Earth system. Here, these orbits have been used to find asteroids that have orbits of this kind. We have built a planar family of horseshoe orbits in the Earth–Moon system and determined the points of planar and 1/1 vertical resonances on this family. We have presented examples of orbits generated by these spatial families.  相似文献   

12.
Comparison of motion de-blur algorithms and real world deployment   总被引:2,自引:0,他引:2  
Sebastian Schuon  Klaus Diepold   《Acta Astronautica》2009,64(11-12):1050-1065
If a camera moves fast while taking a picture, motion blur is induced. There exist techniques to prevent this effect to occur, such as moving the lens system or the CCD chip electro-mechanically. Another approach is to remove the motion blur after the images have been taken, using signal processing algorithms as post-processing techniques. For more than 30 years, numerous researchers have developed theories and algorithms for this purpose, which work quite well when applied to artificially blurred images. If one attempts to use those techniques to real world scenarios, they mostly fail miserably. In order to study why the known algorithms have problems to de-blur naturally blurred images we have built an experimental setup, which produces real blurred images with defined parameters in a controlled environment. For this article we have studied the most important algorithms used for de-blurring, we have analyzed their properties when applied to artificially blurred images and to real images. We propose solutions to make the algorithms fit for purpose.  相似文献   

13.
Preventing the weaponization of outer space is one of the most relevant issues of the current space law debate. In recent years discussions on this issue have significantly increased in international fora, such as the UN Conference on Disarmament and the COPUOS. While it has not been possible to arrive at an agreed solution on how to efficiently deal with the problem of possible weaponization of outer space so far, several valuable proposals have been put forward. China and Russia, on the one side, and the European Union, on the other, have taken the lead in this respect. While the former have submitted a proposal for a draft treaty on the demilitarization of outer space, known as the PPWT, the latter has issued a Draft Code of Conduct for Outer Space Activities. Despite the differences between the two proposals, this paper proposes the development of a Chinese, Russian and European common approach aimed at preventing the weaponization of outer space. Although such a goal is undoubtedly challenging, some political and legal factors may enable such cooperation in the not-too-distant future.  相似文献   

14.
曹健  李尚义  赵克定 《宇航学报》2003,24(4):374-377,403
介绍了一种仿真转台用新型叶片式无脉动连续回转液压伺服马达的工作原理,详细分析了拉各瑞(Lugre)摩擦力模型,给出了摩擦力模型的参数辨识方法及在系统中的补偿措施,通过实验研究,得到本新型连续回转马达的摩擦力矩模型,并通过实验对马达的低速及阶跃响应进行了研究。验证了采用摩擦力补偿措施有效地克服了系统的低速爬行及极限环震荡现象,且使马达的性能完全符合仿真转台的需要。  相似文献   

15.
用于结构件的三维编织复合材料   总被引:3,自引:0,他引:3  
三维编织复合材料是由三维编织物(预制件)增强的一种先进复合材料。它具有优良的层间性能和其它的性能,使复合材料制作主承力结构件和高功能制件成为可能。文章主要讨论了三维编织技术和三维编织复合材料的特点、主要研究的内容以及它们的应用等,并对三维编织技术和复合材料的发展做了展望。  相似文献   

16.
介绍 DS8 0 C32 0单片机在共轴式无人直升机机载测控数据采编器中的应用。该机与80 C31/ 80 C32完全兼容 ,但还具有许多新特点 ,正是由于这些新特点在机载测控数据采编器中的应用 ,简化了编程和硬件设计 ,减小了体积和重量 ,提高了可靠性。目前 ,该测控数据采编器参加了某共轴式无人直升机的试飞 ,证明效果良好。  相似文献   

17.
着陆缓冲技术综述   总被引:6,自引:0,他引:6  
着陆缓冲技术是空间飞行器返回技术的重要组成部分。利用着陆缓冲装置可以明显降低降落伞的面积、减小回收系统的重量,同时大幅度降低飞行器着陆时的冲击载荷。近些年来,着陆缓冲技术有了些新的发展。文中对已有的着陆缓冲装置进行了分类,对每种类型的技术性能、使用范围作了评述。  相似文献   

18.
本文用SCL-90症状自评量表方法,对我校三个年级的部分班级进行了测查。分析表明:我院大学生的心理健康状况不容乐观。本文还对学生管理现状提出了进一步改进建议。  相似文献   

19.
A Kereszturi 《Astrobiology》2012,12(6):586-600
The astrobiological significance of certain environment types on Mars strongly depends on the temperature, duration, and chemistry of liquid water that was present there in the past. Recent works have focused on the identification of signs of ancient water on Mars, as it is more difficult to estimate the above-mentioned parameters. In this paper, two important factors are reviewed, the duration and the volume of water at different environment types on past and present Mars. Using currently available information, we can only roughly estimate these values, but as environment types show characteristic differences in this respect, it is worth comparing them and the result may have importance for research in astrobiology. Impact-induced and geothermal hydrothermal systems, lakes, and valley networks were in existence on Mars over the course of from 10(2) to 10(6) years, although they would have experienced substantially different temperature regimes. Ancient oceans, as well as water in outflow channels and gullies, and at the microscopic scale as interfacial water layers, would have had inherently different times of duration and overall volume: oceans may have endured from 10(4) to 10(6) years, while interfacial water would have had the smallest volume and residence time of liquid phase on Mars. Martian wet environments with longer residence times of liquid water are believed to have existed for that amount of time necessary for life to develop on Earth between the Late Heavy Bombardment and the age of the earliest fossil record. The results of this review show the necessity for more detailed analysis of conditions within geothermal heat-induced systems to reconstruct the conditions during weathering and mineral alteration, as well as to search for signs of reoccurring wet periods in ancient crater lakes.  相似文献   

20.
Old arguments that free O(2) must have been available at Earth's surface prior to the origin of photosynthesis have been revived by a new study that shows that aerobic respiration can occur at dissolved oxygen concentrations much lower than had previously been thought, perhaps as low as 0.05?nM, which corresponds to a partial pressure for O(2) of about 4?×?10(-8) bar. We used numerical models to study whether such O(2) concentrations might have been provided by atmospheric photochemistry. Results show that disproportionation of H(2)O(2) near the surface might have yielded enough O(2) to satisfy this constraint. Alternatively, poleward transport of O(2) from the equatorial stratosphere into the polar night region, followed by downward transport in the polar vortex, may have brought O(2) directly to the surface. Thus, our calculations indicate that this "early respiration" hypothesis might be physically reasonable.  相似文献   

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