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21.
现代战争对作战所涉及的军事地理问题不仅需要定性分析 ,更需要定量分析。建立恰当的数学模型是实现定量分析的关键。文中对城市类战役要点进行了研究并建立了相应的数学模型。 相似文献
22.
城市交通与房地产开发的关联与协调——以广州市为例 总被引:2,自引:0,他引:2
分析广州市房地产开发与交通发展的特征和城市交通与房地产开发间的相互关系,论述了房地产开发对交通的诱导作用和交通对房地产开发的影响.在此基础上,提出城市交通与房地产业开发协调发展的策略. 相似文献
23.
地震应急通讯保障系统的设计与思考 总被引:2,自引:0,他引:2
以华东地震应急联动协作区地震应急演练为例,探讨了演练现场与指挥中心之间异地会商、现场音视频实况转播和测震波形实时显示的主要通讯实现方法;通过比较试验,确定采用WiMAX无线通讯方式传输现场本地数据、采用编解码器传输音视频信号时,双向视频传输需使用2对编解码器,但1对编解码器上就能完全实现异地音频的互通,AV-1600e型编解码器在地震系统目前的卫星应急通讯信道下采用600 kpbs的视频编码率,能提供相对稳定的画面。实践表明,WiMAX无线通讯能较好地扩大野外本地网络通讯半径,编解码器能实现异地音视频互通,但对信道要求较高,效果较难保证。 相似文献
24.
Previous studies of the Green River kerogen only provide apparently contradictory conclusions about the size of the straight-chain aliphatic structures as well as the manner in which these structures form part of the kerogen matrix.The present investigation is an attempt to resolve this contradiction. A mild stepwise oxidation procedure was followed so that extensive degradation of kerogen-derived intermediates could be prevented. Products isolated from each oxidation step were analyzed by conventional GLC techniques, GC-MS, and proton-NMR measurements in order to ascertain the significance of the straight-chain aliphatic structures present in the Green River kerogen.The following results were obtained: (a) Green River kerogen contains a substantial portion (ca 2–4 carbons out of every 10) of straight-chain aliphatic structures which are longer than C4, (b) the kerogen matrix forms a three-dimensional network of non-straight-chain clusters interconnected by long polymethylene cross-links, (c) the ‘core’, in comparison with the ‘periphery’ of the kerogen matrix, contains a greater proportion of straight-chain and branched aliphatic structures which are attached to the kerogen matrix at one terminus, (d) some of the straight-chain structures may exist as physically entrapped components in the kerogen matrix. 相似文献
25.
Anna Belehaki Ljiljana Cander Bruno Zolesi Juergen Bremer Christer Juren Iwona Stanisławska Dimitris Dialetis Michael Hatzopoulos 《Acta Geophysica》2007,55(3):398-409
There are two main objectives of the DIAS (European Digital Upper Atmosphere Server) project. First, it establishes a pan-European repository of raw and derived digital data describing the
state of ionospheric part of the upper atmosphere, which is capable of ingesting real-time information and maintaining historical
data collections provided by most operating ionospheric stations in Europe. Second, the DIAS system produces and distributes,
based on the raw data collection, several operational products required by various user groups for ionospheric nowcasting,
prediction and forecasting purposes. The project completed on May 2006 and the DIAS server operates since then continuously.
The basic products that are delivered are real-time and historical ionograms from all DIAS-affiliated ionospheric stations,
frequency plots and maps of the ionosphere over Europe based on the foF2, M(3000)F2, MUF and electron density parameters, as well as long term prediction and short term forecasting up to 24 hour ahead.
The paper describes use of the ionospheric measurements in the DIAS modelling techniques for specification, predict-tion and
forecasting of the ionosphere over the European region, and details the final products available to the DIAS user community. 相似文献
26.
应急指挥车是气象部门应急系统的重要组成部分。本方案所设计的3G气象应急指挥车通信系统,不仅可以实现多种通信网络的互连互通,还能实现与远程指挥中心的实时数据、语音和视频通信,具有易于部署、应用灵活、性价比高的特点,能有效提高气象部门应对气象灾害和突发公共事件的快速反应能力。 相似文献
27.
The aim of FLOODNET is to provide a communications and data distribution facility specifically designed to meet the demanding temporal requirements of flood monitoring within the European Union (EU). Currently, remotely sensed data are not fully utilized for flood applications because potential users are not familiar with the procedure for acquiring the data and do not have a defined route for obtaining help in processing and interpreting the data. FLOODNET will identify the potential user groups within the EU and will, by demonstration, education and the use of telematics, increase the awareness of users to the capabilities of earth observation (EO) and the means by which they can acquire EO data. FLOODNET will act as a filter between users and satellite operation planners to help assign priorities for data acquisition against previously agreed criteria. The network will encourage a user community and will facilitate cross-sector information transfer, particularly between ‘flood experts’ and administrative decision makers. The requirement for two levels of flood mapping is identified: (1) a rapid, ‘broad-brush’ approach to assess the general flood situation and identify areas at greatest risk and in need of immediate assistance; (2) a detailed mapping approach, less critical in time, suitable for input to hydrological models or for flood risk evaluation. A likely networking technology is outlined, the basic functionality of a FLOODNET demonstrator is described and some of the economic benefits of the network are identified. © 1997 John Wiley & Sons, Ltd. 相似文献
28.
This paper investigates trust in the scientists, government authorities and wider risk management team during the ongoing
volcanic crisis in Montserrat, WI. Identifying the most trusted communicator and how trust in information can be enhanced
are considered important for improving the efficacy of volcanic risk communication. Qualitative interviews, participant observations
and a quantitative survey were utilised to investigate the views and attitudes of the public, authorities and scientists.
Trust was found to be dynamic, influenced by political factors made more complex by the colonial nature of Montserrat’s governance
and the changing level of volcanic activity. The scientists were viewed by the authorities as a highly trusted expert source
of volcanic information. Mistrust among some of the local authorities towards the scientists and British Governor was founded
in the uncertainty of the volcanic situation and influenced by differences in levels of acceptable risk and suspicions about
integrity (e.g. as a consequence of employment by the British Government). The public viewed friends and relatives as the
most trusted source for volcanic information. High trust in this source allowed competing messages to reinforce beliefs of
lower risk than were officially being described. The scientists were the second most trusted group by the public and considered
significantly more competent, reliable, caring, fair and open than the authorities. The world press was the least trusted,
preceded closely by the British Governor’s Office and Montserratian Government officials. These results tally well with other
empirical findings suggesting that government ministers and departments are typically distrusted as sources of risk-related
information. These findings have implications for risk communication on Montserrat and other volcanic crises. The importance
and potential effectiveness of scientists as communicators, because of, and despite, the existence of political, cultural
and institutional barriers, is exemplified by this study.
相似文献
Katharine HaynesEmail: Email: |
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