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“吉林一号”商业卫星组星发射成功
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《数字通信世界》 2015年第S1期12-12,共1页
10月7日12时13分,我国在酒泉卫星发射中心用长征二号丁运载火箭成功将1组"吉林一号"商业卫星发射升空。"吉林一号"商业卫星组星包括1颗光学遥感卫星、2颗视频卫星和1颗技术验证卫星,工作轨道均为高约650公里的太阳... 10月7日12时13分,我国在酒泉卫星发射中心用长征二号丁运载火箭成功将1组"吉林一号"商业卫星发射升空。"吉林一号"商业卫星组星包括1颗光学遥感卫星、2颗视频卫星和1颗技术验证卫星,工作轨道均为高约650公里的太阳同步轨道。其中,"吉林一号"光学A星是我国首颗自主研发的高分辨率对地观测光学成像卫星。 展开更多
关键词 太阳同步轨道 卫星发射 商业卫星 光学成像 卫星技术 对地观测 高分辨率 技术验证 光学遥感 卫星入
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Assessing the genetic integrity of captive and wild populations for reintroduction programs:the case of Cabot's Tragopan in China 被引量:1
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作者 董路 牛文慧 +4 位作者 周祯婷 许育诚 孙岳 Huw Lloyd 张雁云 《Chinese Birds》 2011年第2期65-71,共7页
Reintroduction of captive-bred animals into suitable habitats is an important technique for the long-term conservation and recovery of populations of endangered species in fragmented landscapes.Inbreeding depression i... Reintroduction of captive-bred animals into suitable habitats is an important technique for the long-term conservation and recovery of populations of endangered species in fragmented landscapes.Inbreeding depression is an inherent risk when using captive populations for reintroduction programs and needs to be carefully assessed prior to reintroduction.In this study,we evaluated inbreeding levels within a captive breeding program and one remnant wild population of Cabot's Tragopan (Tragopan caboti),an endangered pheasant species endemic to China,for which reintroduction is now an essential conservation strategy for long-term population persistence.Fifteen highly polymorphic microsatellite loci were developed to genotype individuals.Inbreeding coefficients (FIS) reveal that there is no evidence of inbreeding within the Tragopan Breeding Center of Beijing Normal University (TBCBNU) captive population and the remnant population from the Wuyi-Yandang Mountains.Diversity of origin,large founder population size and a rational breeding strategy are the most critical factors preventing inbreeding depression within the TBCBNU captive population.We suggest that the TBCBNU population is a suitable candidate stock for T.caboti reintroduction programs and that there is an urgent need to better coordinate and strengthen reproduction management of captive T.caboti populations to sustain the long-term ex situ conservation of the species. 展开更多
关键词 Tragopan caboti REINTRODUCTION INBREEDING microsatellites
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Enhanced multiple access schemes for future broadband satellite communications
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作者 贾敏 顾学迈 郭庆 《Journal of Central South University》 SCIE EI CAS 2010年第1期117-122,共6页
A new structure of next generation integrated communication system was proposed, which is composed of space segment based on satellites and terrestrial segment. Moreover, the characteristics of enhanced multiple acces... A new structure of next generation integrated communication system was proposed, which is composed of space segment based on satellites and terrestrial segment. Moreover, the characteristics of enhanced multiple access schemes based on orthogonal frequency division multiplexing (OFDM) technique were analyzed for satellite links. However, OFDM is a doubtful candidate as its higher peak-to-average power ratio (PAPR) that causes the distortion of high power amplifier (HPA). Furthermore, different schemes were evaluated and compared in terms of the HPA nonlinearity and the link level performance in detail. And the pilot-aided channel estimation and equalization techniques were also considered for analyzing the problem. Simulation results show that the bit error rate (BER) and block error rate (BLER) performance of orthogonal frequency division multiple access (OFDMA) outperforms that of single carrier-frequency division multiple access (SC-FDMA) for the satellite links in the proposed structure, though discrete Fourier transform-spread OFDM DFT-S OFDM has low PAPR, especially the BER performance of OFDMA is 3.6 dB larger than that of SC-FDMA at the target BER. 展开更多
关键词 SATELLITE orthogonal frequency division multiplexing discrete Fourier transform high power amplifier channel estimation
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High Throughput Satellite System Capacity Analysis and Application Forecast 被引量:2
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作者 DENG Heng PENG Fei +2 位作者 YUAN Jun SHEN Yufei Pan Ji 《Aerospace China》 2016年第4期30-40,共11页
With the development of large numbers broadband Internet access,global satellite communications is moving towards High Throughput Satellites(HTS).Now,USA,Canada,Europe,Thailand,Japan,United Arab Emirates,Australia hav... With the development of large numbers broadband Internet access,global satellite communications is moving towards High Throughput Satellites(HTS).Now,USA,Canada,Europe,Thailand,Japan,United Arab Emirates,Australia have already developed HTS systems.However,there is little research to analyze the factors influencing high throughput.Thus,from the design perspective,the throughput of HTS and influencing factors are calculated and compared at a system level.Finally,the application of HTS is analyzed and forecasted. 展开更多
关键词 HTS Ka broadband telecommunication satellite Q/V band
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THE IMPROVEMENT OF INFARCTED MYOCARDIAL CONTRACTILE FORCE AFTER AUTOLOGOUS SKELETAL MUSCLE SATELLITE CELL IMPLANTATION
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作者 钟竑 朱洪生 张臻 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2002年第1期11-15,共5页
Objective To study the improvement of infarcted myocardial contractile force after autologous skeletal muscle satellite cell implantation via intracoronary arterial perfusion. Methods Skeletal muscle cells were harves... Objective To study the improvement of infarcted myocardial contractile force after autologous skeletal muscle satellite cell implantation via intracoronary arterial perfusion. Methods Skeletal muscle cells were harvested from gluteus max of adult mongrel dogs and the cells were cultured and expanded before being labeled with DAPI (4’, 6-diamidino-2-phenylindone). The labeled cells were then implanted into the acute myocardial infarct site via the ligated left anterior descending (LAD) coronary artery. Specimens were taken at 2nd, 4th, 8th week after myoblast implantation for histologic and contractile force evaluation, respectively. Results The satellite cells with fluorescence had been observed in the infarct site and also in papi- llary muscle with consistent oriented direction of host myocardium. A portion of the implanted cells had differen- tiated into muscle fibers. Two weeks after implantation, the myocardial contractile force showed no significant difference between the cell implant group and control group. At 4 and 8 week, the contractile force in the cell implant group was better than that in control group. Conclusion The skeletal muscle satellite cells, implanted into infarct myocardium by intracoronary arterial perfusion, could disseminate through the entire infarcted zone with myocardial regeneration and improve the contractile function of the infarcted myocardium. 展开更多
关键词 acute myocardial infarction skeletal muscle satellite cell cell implantation myocardial regeneration myocardial contractile force
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政府涉入型对外卫星电视与NWICO
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作者 冯建三 《西南民族大学学报(人文社会科学版)》 CSSCI 北大核心 2014年第10期160-167,共8页
CNN英语国际频道开台,象征了新闻不平衡已由文字电讯延伸到了影音视讯。但其后新兴的跨境卫星视频群起亮相,固然没有根本挑战其地位,却已提供了新来源,既让不同国家得以自行在国际间发声,也对各国事件的分析与解释,提供了有别于CNN的内... CNN英语国际频道开台,象征了新闻不平衡已由文字电讯延伸到了影音视讯。但其后新兴的跨境卫星视频群起亮相,固然没有根本挑战其地位,却已提供了新来源,既让不同国家得以自行在国际间发声,也对各国事件的分析与解释,提供了有别于CNN的内容与角度。其中拉美的TeleSur视频有别于欧亚非中东等国,它的成立与运作从一开始就清楚地继承了NWICO的古典关怀:由政府代表人民出资、朝向公共治理而成立的非商业之区域合作事业。 展开更多
关键词 新世界信息 传播秩序 政府涉型对外卫星电视 南方电视台 新华社 传播学
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