检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
机构地区:[1]黄淮学院农林科学系,河南驻马店463000 [2]驻马店市园林管理处,河南驻马店463000
出 处:《生态科学》2008年第6期474-477,共4页Ecological Science
基 金:基金:国家科技支撑计划项目(2007BAO57B02);驻马店科技攻关计划项目(0610007)
摘 要:基于投影寻踪回归方法,对李小食心虫Grapholitha funebrana在美国杏李上分布的多维数据进行投影降维和寻优处理,结果表明美国杏李园李小食心虫的空间分布与美国杏李的方位和层次有密切关系,李小食心虫的幼虫主要聚集在美国杏李的中部和外部,并以东面和北面为重,南西两面和内部轻。在方位层次和方位上对李小食心虫的密度进行预测,预测结果与真实值符合优度较高。基于投影寻踪回归方法可以减少因变量太多所带来的误差影响,自变量越多估计值越精确变量之间微小的差距都能显示出很高的权重值。Projction dimension reduction and optimaztion of dimentional data about the distribution of Grapholithafunebrana in U.S.A plum orchard were done based on projection pursuit(PP) technology. The result showed that spatial distribution of Grapholitha funebrana and directions and direction-levels were closely related on U.S apricot and plum. The larvae of Grapholitha funebrana aggregated on the centre and external of U.S plum, with much more larvae on the east and north. The density of Grapholitha funebrana forecasted in directions and direction-levels showed that the forecast and reality were in high optimization. The errors due to variables could be reduced by projection pursuit technology. Besides, the estimate could be much more accurate when there were more variables; and the tiny gap could show a very high weight value.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.94