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991.
The implementation of new type industrialization and urbanization and agricultural modernization strategies lacks of a major hand grip and spatial supporting platform, due to long-term existed "dual-track" structure of rural-urban development in China as well as un- stable rural development institution and mechanism. It is necessary to restructure rural pro- duction, living and ecological space by carrying out land consolidation, so as to establish a new platform for building new countryside and realizing urban-rural integration development in China. This paper develops the concept and connotation of rural spatial restructuring. Basing on the effects analysis of industrialization and urbanization on rural production, living and ecological space, the mechanism of pushing forward rural spatial restructuring by carry- ing out land consolidation is probed. A conceptualization of the models of rural production, living and ecological spatial restructuring is analyzed combining with agricultural land con- solidation, hollowed villages consolidation and industrial and mining land consolidation. Fi- nally, the author argues that a "bottom-up" restructuring strategy accompanied by a few "top-down" elements is helpful for smoothly pushing forward rural spatial restructuring in China. In addition, the optimization and restructuring of rural production, living and ecological space will rely on the innovations of regional engineering technology, policy and mechanism, and mode of rural land consolidation, and more attentions should be paid to rural space, the foundation base and platform for realizing urban-rural integration development.  相似文献   
992.
The implementation of new type industrialization and urbanization and agricultural modernization strategies lacks of a major hand grip and spatial supporting platform, due to long-term existed "dual-track" structure of rural-urban development in China as well as unstable rural development institution and mechanism. It is necessary to restructure rural production, living and ecological space by carrying out land consolidation, so as to establish a new platform for building new countryside and realizing urban-rural integration development in China. This paper develops the concept and connotation of rural spatial restructuring. Basing on the effects analysis of industrialization and urbanization on rural production, living and ecological space, the mechanism of pushing forward rural spatial restructuring by carrying out land consolidation is probed. A conceptualization of the models of rural production, living and ecological spatial restructuring is analyzed combining with agricultural land consolidation, hollowed villages consolidation and industrial and mining land consolidation. Finally, the author argues that a "bottom-up" restructuring strategy accompanied by a few "top-down" elements is helpful for smoothly pushing forward rural spatial restructuring in China. In addition, the optimization and restructuring of rural production, living and ecological space will rely on the innovations of regional engineering technology, policy and mechanism, and mode of rural land consolidation, and more attentions should be paid to rural space, the foundation base and platform for realizing urban-rural integration development.  相似文献   
993.
该文旨在探讨中分辨率遥感影像的土地覆盖变化对象识别方法。首先基于植被-不透水层-土壤(VIS)模型,参考OIF指数的信息量进行对象特征指标选取,基于过分割和欠分割指数确定最优分割尺度,对两期SPOT影像进行多时相分割,然后利用卡方变换方法自动选择阈值,进行植被、不透水层、土壤和水体4种土地覆盖类型之间的变化对象识别。精度评价表明,随着对象特征指标包含信息量的不断增加,检测结果的总精度不断提高,其中对影像所有特征指标进行主成分分析并选择前3个主成分作为特征指标组合对土地覆盖变化对象进行识别的总精度最高,为93.9%,Kappa系数为0.824,证明了该方法的有效性。  相似文献   
994.
微藻是指1群真核、单细胞、行光合作用的生物。微藻种类多,分布广泛,有关键生态学功能,也有水产、生物能源应用价值。与模式生物和经济动植物一样,新基因克隆是微藻生物学研究的主要内容。基因组注释、转录组分析和基因分离等依据序列和结构同源性,是从已知到已知的过程;而新基因克隆需锁定序列和验证功能,其中,功能验证是基因克隆的最重要内容。已有的基因功能验证方法有基因敲除、基因沉默、插入突变、基因组编辑等。多种微藻已有遗传转化技术,有望直接采用模式生物和经济动植物的基因功能验证技术克隆新基因。本文归纳了已有新基因功能验证技术,并分析了它们在微藻新基因克隆中的适用性,以促进微藻新基因克隆研究。  相似文献   
995.
?????????????????????????????????????????????????????????????????????????????????????????????÷???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????÷??????????????Ч???  相似文献   
996.
??????μ???????????????????????????????Unscented?任???????????????????????????÷?????????????е???????????????????????????????????????????????Unscented?任??????????????ι????????????????????????λ???????????  相似文献   
997.
LONG Hualou 《地理学报》2014,24(2):211-225
The implementation of new type industrialization and urbanization and agricultural modernization strategies lacks of a major hand grip and spatial supporting platform,due to long-term existed "dual-track" structure of rural-urban development in China as well as unstable rural development institution and mechanism. It is necessary to restructure rural production,living and ecological space by carrying out land consolidation,so as to establish a new platform for building new countryside and realizing urban-rural integration development in China. This paper develops the concept and connotation of rural spatial restructuring. Basing on the effects analysis of industrialization and urbanization on rural production,living and ecological space,the mechanism of pushing forward rural spatial restructuring by carrying out land consolidation is probed. A conceptualization of the models of rural production,living and ecological spatial restructuring is analyzed combining with agricultural land consolidation,hollowed villages consolidation and industrial and mining land consolidation. Finally,the author argues that a "bottom-up" restructuring strategy accompanied by a few "top-down" elements is helpful for smoothly pushing forward rural spatial restructuring in China. In addition,the optimization and restructuring of rural production,living and ecological space will rely on the innovations of regional engineering technology,policy and mechanism,and mode of rural land consolidation,and more attentions should be paid to rural space,the foundation base and platform for realizing urban-rural integration development.  相似文献   
998.
随着计算机海量空间信息存储和处理能力的显著提高,我国基础地理信息数据组织已由传统的分幅方式转向了数据库方式,由此大区域GIS数据库坐标系统转换成为一个亟待解决的问题。本文基于实际生产中较易获取的分幅坐标改正量资料,提出了一种利用Delaunay三角网剖分的GIS数据库的坐标系统转换方法,对大区域内GIS数据库坐标系统分区逐点转换的原理、思路与流程进行了深入探讨,并开展区域性实验对该方法的效果进行了验证。  相似文献   
999.
介绍了极坐标放样法在任意点设站测设曲线中线桩的原理和方法,充分利用全站仪和可编程计算器的优点,可一次设站多次放样,该法具有测站选择灵活,测设速度快,放样点位精度高等优点,是一种很好的放样方法。  相似文献   
1000.
离散三角网格系统距离量测方法   总被引:1,自引:0,他引:1  
根据离散三角网格系统的空间分布特征,构建新型的十二连通拓扑空间几何距离量测方法,根据三角网格的边的方向性差异性及空间分布格局特征提出一种新型的三角网格单元三维IJK坐标系统,给出该坐标系统与传统行列坐标系统的坐标转换方法,推导三角网格系统的距离计算公式,为基于三角网格系统构建的柏拉图立体三角网格部分系统的距离计算奠定了...  相似文献   
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