仿真模型中复杂三维实体集的选择与交互技术研究

鉴于目前商用图形软件包对于复杂模型中三维实体集显示与选择的局限性，本文提出了一种新的判断点与面域从属关系的方法，此方法借鉴计算机图形学中扫描转换填充算法的射线法，并在此基础上对射线法进行扩充和完善，文章同时对三维复杂实体群的交互手段和技术进行了研究，在解决实际问题中取得了良好的效果。     

解决当前农村面临主要的问题的新思路——农业土地集体租赁模式初探

我国当前农村面临的问题主要有三个：农业发展后劲问题，农村人口老龄化及养老保障问题和农村工业化城市人问题。从这三个问题出发，对目前社会上较为流行的多种农业产业化实现模式的设想进行分析和探讨，在分析和探讨当中发现并提出农村土地集体租赁的产业化实现模式是解决这三个问题的有效途径。     

Two Village Ecosystems in the Upper Minjiang River, China： A Comparison of Emergy Flow

By using the concept of emergy and method of emergy analysis, this paper has studied two mountain settlement (village) ecosystems in two aspects: input and output of energy in the agro-systems and the use of fuel energy. The result reveals that the settlement agro-system in the valley of Minjiang River is better in both structure and function than that at the so-called half-high mountain. The former one is higher than the latter one regarding such indices as emergy yield ratio, labor productivity of emergy and emergy sustainable index, but lower than the latter one regarding environmental loading ratio. In terms of fuel emergy, the settlement in the valley enjoys more diversified sources and is less depending on bio-energy while the settlement at the half-high mountain has only one source (i. e. fuel wood), much depending on bio-energy, may exert a greater pressure on environment.     

我国古代立体农业的理论和实践

本文介绍了人类从事农业生产，从简单到复杂模拟自由界生物群落繁衍，生长的简单历较详细地论述了古代农书中有关立体农业的和实践，供我们进一步建立，发展现代立体农业参考。