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国外遥感卫星应用产业发展现状及趋势
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作者 于清川 《军民两用技术与产品》 2018年第20期16-16,共1页
从美国发射其第一颗遥感卫星一陆地卫-1算起的30余年里,世界范围内商业遥感卫星技术已经有了巨大的进步.越来越多的国家和国际团体拥有自己的遥感卫星.除了更多各类的遥感器得以使用外,卫星的图像分辨率和覆盖能力也有了很大的改进.未... 从美国发射其第一颗遥感卫星一陆地卫-1算起的30余年里,世界范围内商业遥感卫星技术已经有了巨大的进步.越来越多的国家和国际团体拥有自己的遥感卫星.除了更多各类的遥感器得以使用外,卫星的图像分辨率和覆盖能力也有了很大的改进.未来的发展更加令人振奋.国外遥感卫星(包括已经发射和计划要发射的卫星)简介是根据从国内外出版物中获得的信息整编而成,旨在给遥感应用提供一个现在和末来图像信息源的总的概念. 展开更多
关键词 遥感卫星 盖范围 地面站
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中国方圆标志认证委员会福建审核中心/福州认证工作站认证公告
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《质量技术监督研究》 2000年第4期44-44,共1页
中国方圆标志认证委员会福建审核中心/福州认证工作是中国方圆标志认证委员会的分支机构,并经中国质量体系认证机构国家认可委员会认可,注册号为SC19。本机构可以同时受理方圆标志产品质量认证和 GB/T19000-ISO 9000质量体系认证,并独... 中国方圆标志认证委员会福建审核中心/福州认证工作是中国方圆标志认证委员会的分支机构,并经中国质量体系认证机构国家认可委员会认可,注册号为SC19。本机构可以同时受理方圆标志产品质量认证和 GB/T19000-ISO 9000质量体系认证,并独立实施质量体系审核。 展开更多
关键词 认证标准 标志认证 GB/T19002 认证工作 核中心 注册编号 公司法人代表 盖范围 产品质量认证 质量体系审核
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On Growth and Covering Theorem for a Kind of Spiral-like Mappings
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作者 LIU Hao CUI Hong-yu LIU Ai-chao 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期488-492,共5页
In this paper, we deduce growth and covering theorem for f(x) by the othermeans where f(x) is strongly spiral-like mapping of type β with order α defined on UnitBall B of complex Banach space and still give gr... In this paper, we deduce growth and covering theorem for f(x) by the othermeans where f(x) is strongly spiral-like mapping of type β with order α defined on UnitBall B of complex Banach space and still give growth upper bound and distortionbound for subordinate mapping. 展开更多
关键词 spiral-like mapping growth and covering theorem subordinate mapping
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Spatial assessment of forest cover and land-use changes in the Hindu-Kush mountain ranges of northern Pakistan 被引量:5
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作者 Sami ULLAH Muhammad FAROOQ +3 位作者 Muhammad SHAFIQUE Muhammad Afra SIYAB Fazli KAREEM Matthias DEES 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1229-1237,共9页
Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and ... Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and forecast forest cover and other land-use changes for the protection and conservation of mountainous environment. The present study deals with the assessment of forest cover and other land-use changes in the mountain ranges of Dir Kohistan in northern Pakistan, using high resolution multi-temporal SPOT-5 satellite images. The SPOT-5 satellite images of years 2004, 2007, 2010 and 2013 were acquired and classified into land-cover units. In addition, forest cover and land-use change detection map was developed using the classified maps of 2004 and 2013. The classified maps were verified through random field samples and Google Earth imagery(Quick birds and SPOT-5). The results showed that during the period 2004 to 2013 the area of forest land decreased by 6.4%, however, area of range land and agriculture land have increased by 22.1% and 2.9%, respectively. Similarly, barren land increased by 1.1%, whereas, area of snow cover/glacier is significantly decreased by 21.3%. The findings from the study will be useful for forestry and landscape planning and can be utilized by the local, provincial and national forest departments; and REDD+ policy makers in Pakistan. 展开更多
关键词 Forest cover changes Land use changes Remote sensing Hindu-Kush Mountain regions SPOT satellite images
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3eta Diversity of Mbuna in Lake Malawi
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作者 L.G. Kanyumba W.J. Changadeya +2 位作者 A.J.D. Ambali L.A. Kamwanja E.K.W. Kaunda 《Journal of Environmental Science and Engineering》 2011年第11期1496-1506,共11页
Molecular and field studies suggest that Mbuna have limited migration range and are restricted by habitat discontinuities especially in areas where rocky habitats are separated by stretches of sand. This study estimat... Molecular and field studies suggest that Mbuna have limited migration range and are restricted by habitat discontinuities especially in areas where rocky habitats are separated by stretches of sand. This study estimated regional diversity of Mbuna in Lake Malawi. The estimated fl-diversity for all sites was 114.5 Mbuna suggesting that there was high level of allopatrism for the species complex. Sympatric index was low in the two regions of southern and northern lake and the observed high-end richness strongly correlated with minimum species richness. The sympatric index for the whole lake was 0.8, with non-monotypic species complexes showing declining values of sympatric index and the decline was dependent on the geographical scale of the area covered. The northern region sites had mean habitat ranking of 84.5% while the southern sites had habitat ranking of 56.7% supporting the observation that there are more rocky habitats in the northern part of the lake than in the southern. Implications of habitat ranking are discussed in terms of species abundance and richness. 展开更多
关键词 Mbuna beta diversity species richness species abundance
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Effectiveness of Nature Reserves for Natural Forests Protection in Tropical Hainan: a 20 Year Analysis 被引量:4
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作者 YU Bowei CHAO Xuelin +2 位作者 ZHANG Jindong XU Weihua OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2016年第2期208-215,共8页
The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, ... The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, the world′s most populous nation supporting some of the most valuable biodiversity hotspots in the world. In this study, we conducted a long-term and large-scale analysis of the effectiveness of 20 of the earliest nature reserves established in Hainan Province, an island home to among the highest concentration of plants and animals in China. Remote sensing imagery from 1988, 1998, and 2008 were analyzed to investigate the temporal and spatial changes of natural forests in these nature reserves and surrounding areas. We also conducted transition matrix analysis and principle component analysis to identify the driving factors that affect the protection effectiveness of nature reserves. The results were as follows: 1) During the 20-year period from 1988 to 2008, natural forests coverage of the 20 studied nature reserves dropped 2.34 percentage points, whereas the natural forests coverage dropped 11.31 percentage points in a 0–5 km outside reserve buffer and 9.36 percentage points in a 5–10 km outside reserve buffer, indicating a significant inhibitory effect of the nature reserves on the loss of natural forests. 2) Natural forests coverage dropped in 60% of the studied nature reserves during the 20-year period, suggesting a poor protection effectiveness of these reserves, while the coverage proportion showed some increase(0%/yr–5%/yr) in other reserves. 3) Expansion of rubber and pulp forests as part of a booming economy were the main factors affecting the effectiveness of the nature reserves for conserving natural forests in Hainan Province. The results of this study provide an important empirical basis for the protection of natural forests in Hainan Province, which can be used as a blueprint for nature reserve evaluation in other places in China. 展开更多
关键词 nature reserve natural forests reserve effectiveness Hainan Province China
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CDMA与GSM之比较
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作者 彭容 《黑龙江通信技术》 1996年第3期12-17,共6页
CDMA数字蜂窝通信技术具有系统容量大,抗干扰性能强、话音质量好、功耗低的优点,目前被人们所关注。本文就覆盖范围、系统容量、话音质量等方面对CDMA和GSM做了比较。
关键词 CDMA GSMN 盖范围 系统容量 话音清晰度 满意度
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未来的手机做什么
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《新世纪周刊》 2007年第15期147-147,共1页
手机已经成为人们生活的一部分,甚至已经成为身体官能的延伸。现在的手机,不再只是打电话或拍照片。
关键词 智能手机 上网 全球定位系统 热点 无线互联 无线技术 超文本链接 浏览器 盖范围 官能
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