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Forest landscape patterns dynamics of Yihe-Luohe river basin 被引量:4
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作者 DINGShengyan SHANGFude +2 位作者 QIANLexiang CAOXinxiang LIShuang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期153-162,共10页
Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of t... Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of the typical region in the middle of the Yihe-Luohe river basin. These indices include patch number, mean patch area, fragment index, patch extension index, etc. The results showed that: (1) There was a rapid increase in the number of patch and total area from 1983 to 1999 in the study area. The fragment degree became very high. (2) The area of all the forest patch types had witnessed great changes. The fractal degree of each forest patch type became big from 1983 to 1999. The mean extension index of Robinia pseudoacacia forest, non-forest, shrub forest, sparse forest, and Quercus species forest increased rapidly, but that of economic forest became zero. The fractal dimension each showed that forest coverage has been promoted. (3) The changes of landscape patterns were different in different geomorphic regions. From 1983 to 1999 the vegetation cover area, the gross number and the density of patch, diversity and evenness of landscape were all reduced greatly in gullies and ravines, but the maximum area and the mean area of patch types were increased. In hilly region, both the forest cover area and the number of patch increased from 1983 to 1999, but the mean area of patch was reduced greatly. In mountain region, even though the area under forest canopy reduced from 1983 to 1999, the patch number was increased greatly, the mean area of all patch types was reduced, the extension index, diversity index and evenness index of landscape were all increased. Furthermore, because of different types of land use, human activity and terrain, the vegetation changes on northern and southern mountain slopes were different. According to these analyses, the main dri 展开更多
关键词 FOREST landscape pattern DYNAMICS geomorphic zone Yihe-Luohe river basin Luoning County CLC number:S718.5 Q948.2 p901
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夏日倾情 NTT DoCoMo FOMA手机五款
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《数字通信》 2005年第12期18-20,共3页
NEC N901iS N901iS由NEC公司生产制造。N901iS产品一改N900i以来的流线设计,回归到NEC传统设计风格,其商品化轮廓与在国内推出的N840等手机有些相似。作为3G手机,N901iS使用了双镜头配置,其中主摄像头为200万偈素(100万有交像素... NEC N901iS N901iS由NEC公司生产制造。N901iS产品一改N900i以来的流线设计,回归到NEC传统设计风格,其商品化轮廓与在国内推出的N840等手机有些相似。作为3G手机,N901iS使用了双镜头配置,其中主摄像头为200万偈素(100万有交像素),而用于双向视频通话的副摄像头则为10万像素,并且都使用了CCD感光器件。 展开更多
关键词 FOMA手机 NEC公司 N901iS 富士通公司 F901iS 松下公司 p901iS
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NXPP89LPC901单片机汽车起动保护控制器设计 被引量:2
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作者 邹红文 马利民 张勇英 《国外电子元器件》 2008年第7期54-56,共3页
在汽车发动机起动时,若发动机起动后起动机不能及时断电,将会烧毁起动机或损坏飞轮齿环;若变速器不在空档位置起动,则起动机的瞬间动力将使汽车位移,还可能引起交通事故和人身安全。为此介绍一种利用NXPP89LPC901单片机控制的汽车起动... 在汽车发动机起动时,若发动机起动后起动机不能及时断电,将会烧毁起动机或损坏飞轮齿环;若变速器不在空档位置起动,则起动机的瞬间动力将使汽车位移,还可能引起交通事故和人身安全。为此介绍一种利用NXPP89LPC901单片机控制的汽车起动保护控制器,通过检测汽车起动开关、变速箱档位、发动机转速,实现对汽车发动机起动过程检测和保护。起动保护控制器在发动机起动过程中通过采用逐个关闭打开负载系统,解决汽车发动机过程中因起动电流大而对汽车电源的冲击影响,延长了电瓶寿命。 展开更多
关键词 汽车 起动机 起动保护 NXp p89LpC901 单片机
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