中国气象卫星的发展及应用

文章回顾了中国气象卫星的发展历史、所提供的服务和应用。中国气象卫星是在全球气象卫星发展的浪潮中发展起来的。经过40多年的发展,极轨和静止两个系列的气象卫星已经业务运行。中国的气象卫星工程由卫星、运载火箭、发射、测控和地面应用5大系统组成。地面系统作为气象卫星工程大系统中的重要组成部分,对卫星应用效益起重要的作用,在卫星发射后对卫星有效荷载进行运行管理,实施从卫星下传数据的接收、处理、分发、应用和服务。中国气象卫星投入业务运行以后,为改善天气预报、环境监测和短期气候预测提供了有用的信息。在天气预报领域,为台风、暴雨、冰雹 、暴雪、沙尘暴、龙卷风等灾害性天气的预报提供了更有力的手段;在短期气候预测领域,提供了更多有用的参数,如海表水温、雪盖、植被指数等;在环境监测领域,在洪涝、森林草原火情、沙尘暴、雪灾和海冰等监测中发挥了重要作用。现阶段,中国气象卫星面临的最大机遇和挑战在于提高产品的精度,为定量应用服务。其内容涵盖气象卫星的空间段和地面段,并且与数值天气预报本身也有密切的关系。气象卫星为数值天气预报提供全球资料,数值预报模式为气象卫星提供定量产品推导的背景场。气象卫星与数值天气预报协同工作,才能促进气象卫星应用水平的提高。     

发展空间科学是建设世界科技强国的重要途径

习近平总书记在2016年提出了建设世界科技强国"三步走"的战略,为我们设立了宏伟的目标。要想实现这个目标,我们国家在前沿基础研究领域就必须加大投入,实现重大突破。长期以来,作为发展中国家,我国在空间科技领域的投入,大都用于应用卫星,比如气象卫星、通信卫星等,而在空间科学卫星领域少有投入。纵观世界科技发展,重大基础前沿的突破逐渐依赖于国家重大科技工程,其一是建设地面大科学装置,如加速器、大型天文望远镜等;其二就是在空间科学领域里的投入,发射科学卫星。1957年以来美国等航天强国在空间科学领域里多次获得诺贝尔奖就充分说明了这一领域在实现基础前沿领域重大突破的作用。由此可见,发展空间科学是建设世界科技强国的一个非常重要的方面和实现途径。     

Simultaneous observation techniques in astronomy

Modern optics and electronics have now reached the stage where various techniques can be adopted to carry out combined and simultaneous astronomical observations of the same objects in order to understand their nature. This requires not only an administrative but also a technical coordination, e.g. to allow the simultaneous acquisition of data from two different satellites or from satellites and telescopes at the earth's surface.     

普通固态硬盘在广播级硬盘播出上载服务器中的应用

在硬盘播出系统中,上载存储服务器是安全播出的重要保障。由于广播电视行业的特殊性,对数据的存储安全、稳定以及读取速度都有着非常苛刻的要求,这也决定了广播电视设备的昂贵与单一性。面对昂贵的广播电视器材价格,一些地方电视台只能通过自行搭建系统成为越来越多地方电视台的选择。在数据存储方面,鉴于广播电视的特殊性,市场上普遍使用的硬盘在这个行业中失去了优势。随着数字信息化时代的到来,存储也迎来了大跨越的新时代,如何让低成本的普通民用硬盘运用到广播电视行业中来?这是目前所有地方电视台都需要解决的问题。现南宁电视台首次尝试将民用普通固态硬盘SSD采用RAID方式组成磁盘阵列使用在上载存储服务器中,该系统搭建两年以来,运行良好,读取速度稳定,安全系数高等优势慢慢展现出来,本文详细分析了该系统的搭建及运行情况。     

European policies on space science and technology 1960–1978

This paper discusses the key political issues involved in current and past attempts to come to a common European space programme. The history of European space policy has been characterised by different perceived interests on the national level. In the 1960s financial and above all political problems shattered the ideal of a unified Europe, and European collaboration in space largely failed. Political disagreement — particularly between the three main European space nations, France, F.R. Germany and the United Kingdom — continued into the 1970s. Finally, a renewed attempt for European technological cooperation was made by the setting up of the European Space Agency. Since its creation, in 1974, Europe's space policy has again been facing political uncertainty. As a result of the divergence of national interests and of inappropriate industrial policies at the European level, Europe is now unable to cope with the reality of competitive space markets (satellites, launchers, ground equipment, tracking stations, etc.). If Europe is to become competitive in the commercial space market, industrial policies will have to be altered — with possible profound consequences for the structure and existence of the European Space Agency. If, alternatively, political disagreements about joint European programmes are not resolved, and if Europe as a consequence fails to make a (already late) start in the commercial space sector, the consequences may be far-reaching. The European countries may then either revert to separate national (or bilateral) programmes or become largely dependent on outside suppliers for space technology products. Europe may thus find itself without any share of the world space market.     

The concept of a university of the world

Abstract

Long‐distance education is now possible because of advancements and improvements in international telecommunications. This paper sets forth the concept of a “University of the World” in which students use computers, radio, and television to take courses in their chosen discipline and, in return, receive course credit and even academic degrees. The author describes the concept, its educational goals and objectives, the availability of courseware, the impact of global instructional technology, and questions of cost and technological capability. The organization, governance, funding, and operation of the University of the World are also described, including remarks on the benefits of membership and the functional value as seen from the student's perspective.     

Information technology in rural emergency management

Abstract

Rural communities face a multitude of hazardous conditions—from blizzards, floods, droughts, and insect infestations caused by nature to hazardous material spills, transportation accidents, and dam failures that result from human activities. Information technology offers to rural emergency managers potentially important tools with which to better plan, alert, and respond to disasters.

Three case studies are presented about uses of different technologies. Each technology is currently in place, but not in widespread use. The first case is the use of a microcomputer in a rural Minnesota county to manage emergency resources, aid planning, and other important tasks. The second case uses cable television as a two‐way alerting link to fire, emergency medical, and police systems. The third case involves the use of satellites to form a statewide communication system among emergency service offices. Each use of information technology clearly contributes to improved emergency management, but widespread application is necessary before the full impact of information technology in rural emergency management can be felt.     

我国广播电视集团改革的路径及目标

我国广播电视集团步报业发展变迁后尘,从＂事业单位企业化管理＂起步,经历事业单位、企事业混合型单位、企业单位的形态变更,从单纯依靠国家财政补贴,逐步开始＂自主经营,自负盈亏,自我积累,自我发展＂,从事业、行业向产业方向发展。本论文对我国广电集团目前普遍采取的节目与广告、宣传与经营＂两分开＂做法带来新的体制性障碍以及我国广电集团在产业化进程中的三次变革进行剖析,论证了广电集团体制改革的路径及目标。     

中国极轨气象卫星遥感技术的发展

中国极轨气象卫星遥感技术的研究始于20世纪70年代。为获取昼夜云图,1974年开始研制48转/分可见红外扫瞄辐射计,可见和红外图像地面分辨率分别为4和5.8毫弧度。1977年“FY-1”气象卫星进入工程研制,开始使用辐射致冷器冷却的HgCdTe红外探测器研制120转/分扫瞄辐射计,图像地面分辨率均提高到3.6毫弧度。随着HgCdTe探测器性能的提高和数字化技术的进步,1982年开始研制360转/分5通道扫瞄辐射计,其中2个可见光通道用于海洋水色观测,图像地面分辨率1.2毫弧度。1988年9月“FY-1A”卫星首次发射,在1990年9月发射的“FY-1B”卫星上,扫描辐射计稳定工作了2年,图像清晰,红外辐射定标精度优于1K。为同时满足气象和海洋水色观测的需要,1989年提出研制十通道扫瞄辐射计,它不仅设有NOAA卫星AVHRR/3的6个探测通道,还有4个通道分别用于海洋水色观测和大气校正。该仪器装载在1999年5月和2002年5月入轨的“FY-1C”和“FY-1D”卫星上,运行寿命分别超过4年和9年。为发展新的遥感仪器和提高观测能力,在2002年发射的“SZ-3”和“SZ-4”飞船上进行了中分辨率成像光谱仪、多模态微波遥感器、太阳紫外光谱探测仪、地球辐射收支仪的遥感试验,并开展了大气红外分光计的研制,为中国极轨气象卫星从二维图像向三维立体观测建立了技术基础。第二代业务气象卫星“FY-3A”和“FY-3B”分别于2008年5月和2010年11月发射,各装载了10台遥感仪器,获取的数据用于天气预报和气候变化研究。中分辨率成像光谱仪有20个探测通道,可对全球表面状况做较精细的快速重复观测。     

Telecommunications in rural America: An appraisal and a prediction

Abstract

Rural America has historically been plagued with a disproportionate shortage of health, education, and other public services. However, the application of rapidly changing telecommunications technologies can alleviate many of the problems associated with these isolated and “technologically undernourished” areas. Technologies such as low‐power television, direct broadcast satellites, and satellite‐fed cable services offer the opportunity for building a rural telecommunications network and thus improving services and the quality of life. However, in order for this goal to be realized, the economic constraints presented by insufficient consumer demand and unprofitable markets must be overcome. Direct government subsidization or increased support of projects may be necessary to encourage the private sector to increase investment in telecommunications facilities in rural communities.     

我国信息产品特征价格模型研究——以有线数字电视产品为例

本文基于特征价格理论,以有线数字电视为例对我国信息产品市场的具体特征进行了分析,建立了我国有线数字电视业务的特征价格模型。并基于该模型,对我国有线数字电视基本包业务价格进行了研究,发现目前我国有线数字电视基本业务价格与模拟电视节目数量和维护费用,以及付费频道的数量之间存在一定的关系。     

塑造电视媒体网站 培育电视媒体品牌——基于美国电视媒体网站的分析

本文从品牌管理的视角对美国电视媒体网站进行深入分析,研究表明电视媒体网站是电视媒体的品牌延伸,专注于电视媒体网站的建设有助于培育电视媒体品牌。本文的观点期望为国内相关理论研究和实践工作提供一点启示。     

Analyzing the public discourse on works of fiction – Detection and visualization of emotion in online coverage about HBO’s Game of Thrones

This paper presents a Web intelligence portal that captures and aggregates news and social media coverage about “Game of Thrones”, an American drama television series created for the HBO television network based on George R.R. Martin’s series of fantasy novels. The system collects content from the Web sites of Anglo-American news media as well as from four social media platforms: Twitter, Facebook, Google+ and YouTube. An interactive dashboard with trend charts and synchronized visual analytics components not only shows how often Game of Thrones events and characters are being mentioned by journalists and viewers, but also provides a real-time account of concepts that are being associated with the unfolding storyline and each new episode. Positive or negative sentiment is computed automatically, which sheds light on the perception of actors and new plot elements.     

The Digital Future of Terrestrial Advertiser-supported Television 1

The digital transmission of signals greatly increases the channel carrying capacity of the broadcast spectrum and provides scope for a substantial increase in the number of television channels transmitted terrestrially in each broadcasting market. A simple model of a hypothetical advertiser-supported television market shows that with increased channel numbers the average audience size for programmes and channels will decline, advertising revenue per channel will decline, programme costs per audience member will increase, and average profit per channel will decline. In practice, with digital terrestrial television the number of new channels licensed will continue to be subject to government regulatory decisions. But even with liberalisation of licensing policy, the economics of advertiser-supported television broadcasting will impose severe limitations on the number of new channels that any market can support. Digital interactive television services offer commercial broadcasters the prospect of a new source of revenue. The financial viability of these services, however, is not yet proven. Another unknown factor is the impact that personal video recorders will have on television advertising revenues. The transition from analogue to digital terrestrial transmission will have wide-ranging effects on commercial television viewing, but probably not on the structure and ownership of the television broadcasting industry.     

中文经典阅读在影视艺术教育中的意义与作用

伴随着影视艺术教育的繁荣发展,历史悠久的中文经典,如诗歌、小说、散文却在视觉时代下成长起来的青少年面前陷入了前所未有的低谷。看似并没有大关联的两者却有着很重要的联系——中文经典阅读对于影视艺术教育的作用具有重大的意义。本文先指出中文经典阅读和影视艺术在几个大方面的一致性,并通过这几种一致性,剖析了中文经典阅读在影视艺术教育中的意义和作用。     

载人航天、深空探测和科学卫星三类任务中的空间科学

为落实习近平总书记关于要推动空间科学、空间技术、空间应用全面发展的指示,我国航天事业在近年来出现了可喜的发展。空间科学成为越来越多从事航天事业的大学和科研机构关注的对象。然而,对于空间科学在载人航天、深空探测和科学卫星这三类任务中如何发挥其作用,仍然有不少疑问和困惑。文章从空间科学发展的起源,以及载人航天、深空探测和科学卫星各自的特点,探讨空间科学在其中所起到的作用,并提出政策建议。     

Switching position and range-domain carrier-smoothing-code filtering for GNSS positioning in harsh environments with intermittent satellite deficiencies

Carrier-smoothing-code filtering (CSCF) is widely used in GNSS signal processing to combine code pseudoranges and carrier phases. Position-domain (PD) CSCF is generally more accurate and less sensitive to visible satellite changes than range-domain (RD) CSCF. However, PD-CSCF necessitates at least four visible satellites. Intermittent satellite deficiency with less than four visible satellites is not uncommon in harsh environments like urban canyons. At such deficiency epochs, the PD-CSCF convergence has to break off. This study aims to bridge intermittent deficiency epochs in PD-CSCF without introducing any external information. The proposed solution is called switching RD and PD CSCF in which PD filter is replaced by RD filter at deficiency epochs. Besides detailing the seamless switching algorithms from PD/RD to RD/PD filters, a global RD filter, different from the conventional one, is developed to preserve the correlations among smoothed pseudoranges corresponding to different satellites. Compared to the conventional PD and RD CSCF algorithms, smoother results can be expected from the proposed switching filter, especially after the intermittent deficiency epochs. Experiments are conducted using real BDS signals. Cases with different kinds of deficiency are considered. Superiority of the proposed method is clearly observed from the results.     

中国科学院与“两弹一星”工程

"两弹一星"的成功,是中国大国地位的奠基石。从1955年我国决定发展原子能,到1970年第一颗人造卫星发射成功,在"两弹一星"的研制过程中,中国科学院承担了与核弹、导弹相关的大量配套科技任务,负责整个卫星系统的技术抓总,完成卫星本体的研制,并建立地面测控系统。中国科学院为我国"两弹一星"工程作出了重大贡献。     

中国遥感卫星地面站及其陆地观测卫星数据接收和处理系统

中国遥感卫星地面站是国家重大科技基础设施之一,具备完整的卫星数据接收、传输、存档、处理、分发体系,是我国对地观测领域的核心基础设施之一。地面站的数据接收范围覆盖全国及亚洲的70%疆土。地面站的数据接收系统由天馈伺分系统、跟踪接收分系统、测试分系统、记录与快视分系统、故障诊断分系统、站监控管理分系统、技术支持分系统组成,性能和指标居于世界同类地面站前列。地面站拥有一批国际先进的卫星数据处理与产品生产系统,其产品质量、规格与全球数据产品一致。地面站一系列重要的装置改造和自主创新项目的完成,使卫星数据的接收、处理、存储、检索等系统能力有了显著的提升,可以保证以近实时的速度为用户提供数据产品。地面站运行20余年来,所接收、处理和分发的国内外对地观测卫星数据广泛应用于我国的遥感应用各领域,其中突出的范例有国家重大灾害的监测与评估、全国生态环境质量评价、西部测图、海洋环境近实时监测等国家重大重点项目等。     

An educational tv satellite for India: a critical assessment

The paper first presents the Indian proposal for an educational TV satellite with countrywide coverage (INSAT), and gives a sketch of the methodology applied in assessing this large-scale communications change in India. Efforts in communications planning should be considered from the point of view of their potential for helping large numbers of people to gain access to information (which is one aspect of the fact that half the Indian population lives in abject poverty). A first overview of the results according to such criteria demonstrates that the Indian proposal will be anything but a success. The satellite system cannot meet the needs of the broad population. On the one hand the project creates a large potential for mobilisation of the masses, on the other it is not in a position to transmit programmers, which in their content are to a minimal degree adapted to the needs of the adults. In the field of school broadcasts and teacher training, sufficient results are only reached by versions of the project which must be ruled out for political reasons. The capacity of the project is too restricted to avoid conflicts between individual states. Furthermore, the project benefits the largest language groups at the expense of the minorities.Some of the results are discussed in detail by way of a comparison of the impressive technical capacities of terms. Alternative projects with greater scope and with a decentralised structure (e.g. radio satellites or cassette systems) would be better than TV satellites, but pose problems of generating the information in suitable form. The bottleneck in communication is as much in the creation of differentiated information, as in the techniques of conveying it to the audiences. The final section discusses the background of the Indian interests in ‘educational satellites’.