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1.
<麦田里的守望者>是美国作家J.D.塞林格的一部反映二战后美国青少年生活和思想的杰作.被称为当代美国的"现代经典".以往有关本作品在艺术上的研究成果主要是其语言、叙事、象征等表现手法方面,本文是从对比的角度对文中意象展开分析,分析了作者如何运用意象中的对比使主题得以进一步深化.  相似文献   

2.
具有美好寓意的意象图形是我国传统图案艺术的重要组成部分,它是一种民族内在的文化与精神.论文通过对意象传统图案的艺术概述,结合具体实例分析,论述了意象传统图案在现代首饰中的表现与应用.指出将意象传统图案的深层精神含义,沿用到现代首饰设计之中,可使图案的涵义在运用的过程中释放出现代首饰所要表达的意念,延展出更深层次的精神理念,二者的融合将使现代首饰设计更具文化性与社会性,更多一份文化气息和亲和力.  相似文献   

3.
目前.GPS终端装备已在多个领域有实际应用.并在近年的战争中发挥了关键作用。为提高“导航战”能力.美国不断研究、开发新的GPS终端设备或接收机.并把各种新技术融人设备之中.真正做到了技术为装备服务。本文以美国军用卫星导航终端装备为主进行分析与研究.在此基础上分析典型终端装备及实际应用,  相似文献   

4.
司马杭仁 《航天》2009,(7):46-48
“卡西尼”曾被定为是美国发射的最后1个大探测器.此后美国只研制和发射小型空间探测器.但最近美国又计划研制“木星冰卫环行”核动力探测器.它将是美国航宇局有史以来所建造最大的空间探测器.估计造价在约30亿-40亿美元.  相似文献   

5.
鉴于多年来苏联军事力量的迅速增长,美国国防部长温伯格呼吁大力加强美国的防御能力,要求美国的公民都能了解苏联不断使其武装力量现代化、扩大其规模和向前沿地区部署的情况,也要求他们知道美国和北约军力与苏联军力的对比结果。以下就是温伯格在这两方面所作的论述: 自1981年末以来,苏联已试验了几乎每种核武器系统的新型号。特别是,尽管他们的洲际导弹大多是新型的,是七十年代中、  相似文献   

6.
简述了美国新的天基定位、导航和授时政策的主要内容,并与1996年的全球定位系统政策进行了对比,分析了影响新政策的因素和实质,提出了加强对美国新的政策研究的建议。  相似文献   

7.
液氧/甲烷发动机的应用前景   总被引:5,自引:0,他引:5  
通过对甲烷与煤油以及液氧/煤油发动机与液氧/甲烷发动机性能的对比,分析了甲烷的优点。重点介绍了美国、俄罗斯、欧洲、日本、韩国等国家液氧/甲烷发动机研究的现状。综合考虑各种因素,液氧/甲烷发动机是一种具有广泛应用前景的新型发动机,可用于载人亚轨道飞行、高性能飞机、探空火箭、运载火箭上面级、纳米卫星运载火箭第一级。  相似文献   

8.
2010年1月14日.美国产业和安全局在官方网站上发布了《2011年美国商务部对外政策性出口控制报告》。根据今年提交的报告.美国对之前采取的对外政策性出口控制措施.尤其是2010年采取的出口控制措施进行了回厩营结.报告中.美国公布了对部分国家许可证申请的统计数据。报告认为.禁运和其他特别管制对美国工业产生了经济影响。国务卿认为.这些控制对美国经济产生的负面影响。  相似文献   

9.
MIL-HDBK-338B美军可靠性设计手册介绍   总被引:1,自引:0,他引:1  
1.引言 MIL-HDBK-338.是美国军用可靠性设计手册,指导美军装备研制、采购、使用、维护。该手册总结了美国45年来可靠性工程发展经验.反映了美国20世纪可靠性设计水平。内容丰富、实用性强,从1984年到1998年,有3个版本:MIL-HDBK-338、MIL-HDBK-338A、MIL-HDBK-338B,是当今世界上最全面的可靠性理论与实践权威,因为苏、日、英、法等工业发达国家可靠性工程的发展大约比美国晚起步5~10年.所以美国军用可靠性设计手册,值得中国电子行业.尤其通讯行业研究和运用.  相似文献   

10.
《航天员》2010,(4):12-13
据NASA网站8月19日报道.NASA正在向美国公众征集航天飞机预定任务的“唤醒之歌”.目的是以此“唤醒”美国航天员。  相似文献   

11.
弗兰西斯·司各特·菲茨杰拉德是现代美国著名作家,被称作爵士时代的代言人.他的多数作品描绘的是二十世纪二十年代美国年轻一代的期望、不满和失望.1925年出版的<了不起的盖茨比>是菲茨杰拉德写作生涯的顶点.书中主人公盖茨比从多个角度反映了作者的生活和精神历程,从而被认为是作者的缩影.  相似文献   

12.
The active geophysical rocket experiment North Star was carried out in the auroral ionosphere on January 22, 1999, at the Poker Flat Research Range (Alaska, USA) using the American research rocket Black Brant XII with explosive plasma generators on board. Separable modules with scientific equipment were located at distances of from 170 to 1595 m from the plasma source. The experiment continued the series of the Russian–American joint experiments started by the Fluxus experiment in 1997. Two injections of aluminum plasma across the magnetic field were conducted in the North Star experiment. They were different, since in the first injection a neutral gas cloud was formed in order to increase the plasma ionization due to the interaction of neutrals of the jet and cloud. The first and second injections were conducted at heights of 360 and 280 km, respectively. The measurements have shown that the charged particle density was two orders of magnitude higher in the experiment with the gas release. The magnetic field in the first injection was completely expelled by the dense plasma of the jet. The displacement of the magnetic field in the second injection was negligible. The plasma jet velocity in both injections decreased gradually due to its interaction with the geomagnetic field. One of the most interesting results of the experiment was the conservation of high plasma density during the propagation of the divergent jet to considerable distances. This fact can be explained by the action of the critical ionization velocity mechanism.  相似文献   

13.
VERICUT是美国CGTECH公司开发的世界上先进的数控加工仿真软件。本文以VERICUT6.1.2软件为平台,构建了VMC10数控加工仿真系统。通过一个典型实例展现了仿真、优化的全过程,这将为构建其它数控加工仿真系统提供参考。  相似文献   

14.
Using the data of the Russian KORONAS-F satellite and American GOES spacecraft on solar cosmic ray fluxes associated with powerful events which occurred on the Sun at the end of October - the beginning of November, 2003, calculations of ionization of high-latitude (70° N) atmosphere were carried out. The calculations have shown that the maximum values of ionization for the chosen latitude lie in the range of 50–70 km. The largest ionization was caused by the flare on November 28, 2003. Based on a numerical photochemical simulation it is shown that, as a result of intensification of catalytic cycles with participation of ozone-destroying NO and OH, the concentration of ozone decreased by 30% at ionization maximum altitudes.Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 653–662.Original Russian Text Copyright © 2004 by Krivolutsky, Kuminov, Vyushkova, Kuznetsov, Myagkova.  相似文献   

15.
SVET Space Greenhouse (SG)--the first automated facility for growing of higher plants in microgravity was designed in the eighty years to be used for the future BLSS. The first successful experiment with vegetables was carried out in 1990 on the MIR Space Station (SS). The experiments in SVET SG were resumed in 1995, when an American Gas Exchange Measurement System (GEMS) was added. A three-month wheat experiment was carried out as part of MIR-SHUTTLE'95 program. SVET-2 SG Bulgarian equipment of a new generation with optimised characteristics was developed (financed by NASA). The new SVET-GEMS equipment was launched on board the MIR SS and a successful six-month experiments for growing up of two crops of wheat were conducted in 1996 - 97 as part of MIR-NASA-3 program. The first of these "Greenhouse" experiments (123 days) with the goal to grow wheat through a complete life cycle is described. Nearly 300 heads developed but no seeds were produced. A second crop of wheat was planted and after 42 days the plants were frozen for biochemical investigations. The main environmental parameters during the six-month experiments in SVET (substrate moisture and lighting period) are given. The results and the contribution to BLSS are discussed.  相似文献   

16.
基于光谱特性的高光谱图像压缩方案   总被引:5,自引:2,他引:3  
根据干涉型高光谱成像仪成像特点,提出了一种针对干涉型光谱仪所获得高光谱图像的基于光谱特性的图像压缩方案。由于光谱信息最终从“点”十涉图像中恢复,因此方案中首先通过高精度匹配技术将原始“像面”干涉图像序列“重组”成“点”干涉图像,然后针对“点”干涉图像序列进行压缩。在重组过程中采取基于光流的亚像素级匹配和基于梯度的三角插值算法,实现了高精度的图像匹配重组;在压缩环节利用“点”干涉图像与光谱信息之间的傅立叶变换关系,提出一种能够很好保持频谱特性的基于一维DCT的压缩算法。实验证明,压缩算法总体性能远高于针对“像而”干涉圈序列的压缩算法.很好地控制了光谱信息的失真。  相似文献   

17.
The results of experiments with the DAKON-M convection sensor onboard the Russian orbital segment of the International Space Station are described. A comparison of the sensor measurements with the results of calculation of the quasistatic microacceleration component at the point of installation is made. For this comparison we have used three measurement intervals of the experiments in 2009, during which spacecraft were docked with the station, undocked from it, and actuation of jet engines of the attitude control system took place. When calculating microacceleration, we use the measurement data of the low-frequency MAMS accelerometer, installed on the American segment, and the telemetry data on the ISS rotational motion. This information allowed one to convert the MAMS measurements to the point of installation of the DAKON-M convection sensor. A comparison of sensor measurements with calculated microaccelerations showed sufficiently accurate coincidence between the calculated and measured data.  相似文献   

18.
The use of the Internet has been grown tremendously within the last decade to more than one billion subscribers. The other five billion people on Earth cannot enjoy the possibilities offered by the Internet.The digital divide is everywhere: in the developing as well as in the developed part of the world.In the developing countries basic communication needs (voice, IP access) need to be provided to a large population not living in cities.In the developed part of the world people residing outside the large cities, on the nice country side, have still difficulties to get broadband access. The reason being, that the investment to install the network infrastructure to this minority part of the population is a major part of the total investment for the network. The benefit for the telecom operators is marginal to get these customers on board.In this paper an analysis of the Internet and satellite development is being presented and based on these historical data a prediction of a possible evolution of satellite communications and broadband access is performed.One result is that the capacity of the GEO ring at the Ka-band alone would allow to provide to each individual on Earth in 2050 (assumed to be 10 billion people) a monthly capacity of about 1 Gbyte for a charge of 1$ per month.  相似文献   

19.
The American idea of a Solar Power Satellite was proposed for the first time in 1968 by Peter Glaser in a famous article in Science. This concept has since been the subject of many theoretical studies, and of some limited practical studies (mainly about microwave energy transmission) in the USA with funding from NASA and the Department of Energy (DOE). Some evaluations have been also conducted in Western Europe, particularly within the European Space Agency (ESA). But very little is generally known about the attitude towards SPS of the second main space power: the USSR. Soviet literature on SPS is much less abundant, but it does exist. Very interesting articles on the subject have been written by leading Soviet space experts. Some of these articles are analysed here, and the practical meanings of the ex[ressed opinions, generally very favourable, are investigated in view of the growing Soviet space capability.  相似文献   

20.
The new discipline of astrobiology addresses fundamental questions about life in the universe: "Where did we come from?" "Are we alone in the universe?" "What is our future beyond the Earth?" Developing capabilities in biotechnology, informatics, and space exploration provide new tools to address these old questions. The U.S. National Aeronautics and Space Administration (NASA) has encouraged this new discipline by organizing workshops and technical meetings, establishing a NASA Astrobiology Institute, providing research funds to individual investigators, ensuring that astrobiology goals are incorporated in NASA flight missions, and initiating a program of public outreach and education. Much of the initial effort by NASA and the research community was focused on determining the technical content of astrobiology. This paper discusses the initial answer to the question "What is astrobiology?" as described in the NASA Astrobiology Roadmap.  相似文献   

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