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基于旅游开发的宏观环境因子系统分析   总被引:2,自引:0,他引:2  
本文试图在建立旅游开发环境分析的框架对和旅游环境系统分层的基础上,采聚系统整体观来综合探讨外部宏观环境因子对旅游开发的独立或综合影响以及各因子之间的相互关系,旨在拓宽旅游研究人员以及旅游开发和管理人员的思路,并提供一种综合全面认识旅游环境的分析方法。  相似文献   
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长江中下游地区夏季降水的水汽路径的客观定量化研究   总被引:6,自引:4,他引:2  
叶敏  封国林 《大气科学》2015,39(4):777-788
本文根据中国台站降水资料和NCEP/NCAR再分析资料, 研究了长江中下游地区夏季降水的水汽路径并给出了客观定量化的定义。结果表明:(1)影响长江中下游地区夏季降水的水汽路径主要是来自南界的水汽输送, 据此定义了南界水汽路径的面积、中心强度、向东延伸格点的位置以及边界强度等指标;(2)对各个指标的时间演化特征进行了分析, 南界水汽路径的面积指标和中心强度指标有下降的趋势, 各个指标在20世纪90年代前后都有一个明显的转折, 面积指标、中心强度指标、边界纬向强度指标都有明显的年代际的变化;(3)对各指标与中国夏季降水和前冬海表温度进行相关分析, 夏季南界水汽路径影响我国不同地区的降水, 南界水汽路径的面积指标、中心强度指标与前一年冬季西太平洋的海温呈显著负相关, 与赤道中太平洋和东太平洋前一年冬季的海温呈显著正相关, 即前冬东太平洋发生El Ni?o时, 有利于夏季西太平洋水汽输送增强, 进而有利于长江中下游地区夏季降水偏多。  相似文献   
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近年来,福建省以构建“党委领导、政府负责、部门协同、上下联动、群众参与”的国土资源执法监管共同责任机制为抓手,大力探索将国土资源违法违规行为“发现在初始,解决在萌芽”的新举措,不断创新国土资源执法监管手段,在构建对国土资源违法违规行为做到早发现、早报告、早制止、早查处的新机制上勇于先行先试,取得了喜人成果.2012年,省国土资源厅在莆田、晋江等市(县)探索推行“违法行为即拍即传,查处过程短信预警”的手机执法信息平台试点;2013年,将试点扩大到厦门、长乐、武夷山等9个市(县).2014年年初,省国土资源厅在总结试点经验的基础上,以“科技+制度”为创新要点,以信息化为导向,以一张图为支撑,统一构建集土地和矿产执法于一体的国土资源移动执法监察系统,统一构建新常态下的国土资源执法监察流程.  相似文献   
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A hydraulic power unit(HPU) is the driving "heart" of deep-sea working equipment.It is critical to predict its dynamic performances in deep-water before being immerged in the seawater,while the experimental tests by simulating deep-sea environment have many disadvantages,such as expensive cost,long test cycles,and difficult to achieve low-temperature simulation,which is only used as a supplementary means for confirmatory experiment.This paper proposes a novel theoretical approach based on the linear varying parameters(LVP) modeling to foresee the dynamic performances of the driving unit.Firstly,based on the varying environment features,dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing.Secondly,models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer,and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration.Thirdly,dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters.Finally,the developed HPU is tested in a deep-sea imitating hull,and the experimental results are well consistent with the theoretical analysis outcomes,which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU.The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump.  相似文献   
5.
党的十八届三中全会闭幕后,河南省国土资源系统广大干部职工认真学习贯彻十八届三中全会精神,以十八届三中全会精神为动力,促进当前各项重点工作扎实开展。  相似文献   
6.
面对本国人口的急剧减少,为了确保全国和广域规划体系能最大限度地满足新时期的需要,日本国土交通省决定彻底修改之前的综合国土开发法案,并以新的可持续国土规划来取代全国综合发展规划。本文将介绍日本新的可持续国土规划的制定情况。  相似文献   
7.
叶敏  张宏  泽柏 《山地学报》2006,24(B10):288-293
人类活动、小型哺乳动物行为活动以及自然因素是引起高寒草甸植物群落物种多样性变化的主要因子。一般情况下,高寒草甸植物群落物种多样性与放牧、施肥强度呈单峰曲线。长期过牧使高寒草甸退化严重,而围栏封育能使这种情况受到一定程度的控制,但围栏封育有时不符合“放牧优化假说”。工程活动,小型哺乳动物的活动、冻土退化使高寒草甸植物群落发生演替,物种多样性也随之变化。此外,地形引起水、热、养分的再分配,使不同的生境有着不同的物种多样性。概述各干扰因子及不同干扰频率的不同作用。为保护高寒草甸植物群落物种多样性及制定合理的草地利用制度提供科学依据。  相似文献   
8.
城市现状建筑容积率的分类提取对于有效把握城市用地开发强度以及制定科学合理的控制性详细规划具有重要参考意义。提出了一种主成分分量、主方向、边界指数以及矩形拟合度等多特征分量相结合的超高分辨率卫星影像建筑容积率贝叶斯分类提取方法。基于分类结果,采用阴影面积法与阴影长度法计算容积率并进行精度对比验证。利用WorldView-3卫星影像进行提取实验,并对实验区建筑逐一进行实地调查,结果表明,在容积率计算中,阴影面积法总体精度为93.90%,阴影长度法总体精度为85.19%,阴影面积法较阴影长度法在容积率分类提取精度上优势更突出。  相似文献   
9.
A hydraulic power unit (HPU) is the driving “heart” of deep-sea working equipment. It is critical to predict its dynamic performances in deep-water before being immerged in the seawater, while the experimental tests by simulating deep-sea environment have many disadvantages, such as expensive cost, long test cycles, and difficult to achieve low-temperature simulation, which is only used as a supplementary means for confirmatory experiment. This paper proposes a novel theoretical approach based on the linear varying parameters (LVP) modeling to foresee the dynamic performances of the driving unit. Firstly, based on the varying environment features, dynamic expressions of the compressibility and viscosity of hydraulic oil are derived to reveal the fluid performances changing. Secondly, models of hydraulic system and electrical system are accomplished respectively through studying the control process and energy transfer, and then LVP models of the pressure and flow rate control is obtained through the electro-hydraulic models integration. Thirdly, dynamic characteristics of HPU are obtained by the model simulating within bounded closed sets of varying parameters. Finally, the developed HPU is tested in a deep-sea imitating hull, and the experimental results are well consistent with the theoretical analysis outcomes, which clearly declare that the LVP modeling is a rational way to foresee dynamic performances of HPU. The research approach and model analysis results can be applied to the predictions of working properties and product designs for other deep-sea hydraulic pump.  相似文献   
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