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国外新型一次性运载火箭技术的进展与发展趋势(中)
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作者 孙广勃 《中国航天》 北大核心 2001年第11期18-21,共4页
(三)欧洲 欧洲的阿里安运载火箭在目前的国际商业发射市场上占据着半壁江山,目前正在由阿里安4向阿里安5过渡.截止到2001年9月底,阿里安4火箭已发射106次,并实现了连续64次发射成功.阿里安5也已进行了10次发射.
关键词 欧洲 一次性运载火箭技术 阿里安运载火箭 日本 “海射”系统 发展趋势
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Usage of global navigation systems for detection of dangerous meteorological phenomena 被引量:1
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作者 V F Kravchenko O V Kravchenko +2 位作者 V I Lutsenko I V Lutsenko D O Popov 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期68-74,共7页
The method of dangerous meteorological phenomenon detection using the data of coordinate measurement by receivers of global navigation satellite system (GLONASS) and global positioning system (GPS) is proposed. Th... The method of dangerous meteorological phenomenon detection using the data of coordinate measurement by receivers of global navigation satellite system (GLONASS) and global positioning system (GPS) is proposed. The possibility of thunderstorm courses and strong clouds detection on data of pseudo-distances and altitudes is shown theoretically and confirmed experimentally. 展开更多
关键词 dangerous meteorological phenomenon radio-raying global navigation system PSEUDO-RANGE ALTITUDE
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Effect of mesoscale wind stress-SST coupling on the Kuroshio extension jet
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作者 WEI Yanzhou ZHANG Ronghua +1 位作者 WANG Hongna KANG Xianbiao 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期612-619,共8页
Effect of mesoscale wind stress-SST coupling on the Kuroshio extension jet is studied using the Regional Ocean Modeling System. The mesoscale wind stress perturbation( τ_(MS)) is diagnostically determined from modell... Effect of mesoscale wind stress-SST coupling on the Kuroshio extension jet is studied using the Regional Ocean Modeling System. The mesoscale wind stress perturbation( τ_(MS)) is diagnostically determined from modelled mesoscale SST perturbation(SST_(MS)) by using their empirical relationship derived from corresponding observation. From comparing two experiments with and without the τ_(MS) feedback, it is found that the interactively represented τ_(MS)-SST_(MS) coupling can modulate the kinetic energy along the Kuroshio extension jet, with little effect on the Kuroshio pathway. Similar results are also obtained in three additional sensitivity experiments, which consider half strength of the τ_(MS), and the momentum flux and heat flux effect induced by τ_(MS), respectively. That means simply taking into account the τ_(MS)-SST_(MS) coupling has little effect on improving the simulation of the Kuroshio Current system. 展开更多
关键词 mesoscale wind stress-SST coupling Kuroshio extension surface kinetic energy ocean modeling
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Remote Sensing of Sea Surface Wind of Hurricane Michael by GPS Reflected Signals
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作者 ZHOU Zhaoming FU Yang +1 位作者 XUE Zhengang CUI Hongguang 《Geo-Spatial Information Science》 2006年第1期24-31,54,共9页
In this paper, the propagating geometry and the w av eform of the GPS reflected signals are expatiated in detail. Furthermore, the pr inciple and the method of retrieving sea surface wind are presented. In order to te... In this paper, the propagating geometry and the w av eform of the GPS reflected signals are expatiated in detail. Furthermore, the pr inciple and the method of retrieving sea surface wind are presented. In order to test the feasibility of retrieval, the experiment data obtained by NASA in Hurr icane Michael are used. The result shows that the retrieval accuracy of wind spe ed is about 2 m/s. 展开更多
关键词 GPS reflected signals scattering zone sea surface wind retrieval
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Response of Marine Microalgae,Heterotrophic Bacteria and Their Relationship to Enhanced UV-B Radiation
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作者 ZHOU Wenli TANG Xuexi +2 位作者 XIAO Hui WANG You WANG Renjun 《Journal of Ocean University of China》 SCIE CAS 2009年第1期35-38,共4页
Ozone depletion in the stratosphere has enhanced solar UV-B radiation reaching the Earth surface and has brought about significant effects to marine ecosystems. The effects of enhanced UV-B radiation on marine microal... Ozone depletion in the stratosphere has enhanced solar UV-B radiation reaching the Earth surface and has brought about significant effects to marine ecosystems. The effects of enhanced UV-B radiation on marine microalgae, heterotrophic bacteria and the interaction between them are discussed. The effects on marine microalgae have been proved to occur at molecular, cellular and population levels. Enhanced UV-B radiation increases microalgal flavonoid content but decreases their chlorophyll content and pho- tosynthesis rate; this radiation induces genetic change and results in DNA damage and change of protein content. There have been fewer studies on the effects of UV-B radiation on marine heterotrophic bacteria. Establishment of a microalgal ecological dynamic model at population and commuity levels under UV-B radiation has gradually become a hotspot. The effects of enhanced UV-B radiation on microalgae commtmities, heterotrophic bacterial populations and interaction between them will become a focus in the near future. This paper will make an overview on the studies concerning the effects of enhanced UV-B radiation on marine microalgae and heterotrophic bacteria and the interaction between them. 展开更多
关键词 UV-B radiation EFFECT MICROALGAE heterotrophic bacteria
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Thermal Analyses of Combined Utilization Process of Seawater by Solar Chimney
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作者 王一平 方振雷 朱丽 《Transactions of Tianjin University》 EI CAS 2009年第6期393-399,共7页
It is promising to simultaneously develop multiple products through the combined utilization of seawater by solar chimney technology. A small scale experimental system was set up. The collector temperature, the seawat... It is promising to simultaneously develop multiple products through the combined utilization of seawater by solar chimney technology. A small scale experimental system was set up. The collector temperature, the seawater temperature, and the temperature and humidity of the airflow under the collector were measured. Thermal network analysis of the system was carried out. The results show that the airflow is nearly saturated at the entrance of the chimney, and the mean dry-bulb and wet-bulb temperatures of the airflow have increased by 8.4 ℃ and 9.6 ℃, respectively. The radiation heat transfer between the collector and the sky is the biggest heat loss in the system, which is up to 29.1% on average of the solar energy. However, the water evaporation heat is about 23.6% on average of the solar energy. To reduce the heat loss and enhance the water evaporation, it is necessary to reduce the emissivity and thermal conductivity of the collector and increase the evaporation areas. 展开更多
关键词 solar chimney combined utilization of seawater thermal network enhanced evaporation
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Oil spill detection on the ocean surface using hybrid polarimetric SAR imagery 被引量:2
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作者 LI HaiYan PERRIE William +1 位作者 ZHOU YuanZe HE YiJun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第2期249-257,共9页
Hybrid-polarimetric SAR(synthetic aperture radar) is a new SAR mode, with relatively simple architecture, low cost, and wide swath, which will be carried by several Earth-observing systems from now to the near future.... Hybrid-polarimetric SAR(synthetic aperture radar) is a new SAR mode, with relatively simple architecture, low cost, and wide swath, which will be carried by several Earth-observing systems from now to the near future. Here, we show how the second Stokes parameter of hybrid-polarimetric SAR can be employed to detect oil on the ocean surface using the classic well-known Otsu threshold methodology, in relation to contributions from different polarizations and dampening effects on backscatter intensity, neglecting the specific scattering mechanisms and oil types for an oil-covered surface. The detection methodology is demonstrated to be reliable in three example cases: oil-on-water experiments conducted by the Norwegian Clean Seas Association, natural oil seeps from the Gulf of Mexico, and observations from the Deep Water Horizon oil spill disaster in 2010. 展开更多
关键词 Oil spill detection Hybrid polarization Compact polarimetric SAR Stokes parameters Otsu threshold
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