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1.
周滔  张璞洁 《人文地理》2023,38(1):118-129+157
乡村振兴要求走乡村内生性发展道路,客观认知乡村发展能力的时空分异格局和交互关系对乡村振兴战略实施具有重要意义。本文从农业产业发展、农村基础建设和农民社会生活三个维度构建测度指标体系,并引入面板向量自回归模型识别影响乡村发展能力的敏感因素,以此测度乡村发展能力指数,进而采用探索性时空数据分析方法揭示乡村发展能力的时空交互特征。结果表明:(1)我国中部地区多维乡村发展能力提升,但呈明显的空间异质性,不同维度间差异化显著;(2)中部地区多维乡村发展能力局域空间格局呈现较强的动态性并整体表现出较强的空间依赖关系;(3)邻接地级市多维乡村发展能力的时空交互网络以正向关联为主,局部空间呈差异化的竞合态势。  相似文献   
2.
现代化城市具有总体布局合理、基础设施完善、环境质量优良、第三产业发达等基本特征;国际性城市则主要以经济实力雄厚、国际投资与金融机构众多、科技教育事业发达、城市风貌独特、连接国内与世界经济等为其标志。  相似文献   
3.
Deceptively Similar. Remarks on the History of Model Experiments. The article argues for a reconsideration of what has been called ‘model experiments’ or ‘mimetic experiments’. After providing a short overview of the historical developments and the occurences of such types of experiments, three aspects pertaining to their practical functions are discussed. First, the aspect of control: Model experiments are often employed to get a grasp on phenomena that are otherwise beyond the control of human actors. Second, their aesthetic dimension: Model experiments often employ aesthetic strategies that, far from being epistemic obstacles, establish their function as models and may generate new areas of research. Third, meta‐theories: The practice of experimenting on models is often accompanied by discussions about their representativeness. Albeit triggered by problems in local contexts, this self‐reflective discourse did acquire a more general relevance with the formulation of scaling laws in the 19th century.  相似文献   
4.
Using a compiled list of the vascular flora for 21 islands in the western basin of Lake Erie, Preston's resemblance measure and Connor and Simberlof's Null Hypothesis I were applied to native and alien species subsets in order to examine how these findings fit within the equilibrium theory. Based on Preston's measure, it was found that the similarity of species between island pairs was more likely to fit with MacArthur and Wilson's equilibrium theory when native species were considered than when alien species were considered. Native species have restricted distributions - especially those found on the smaller islands - and appear to be less randomly distributed about the islands. This study also found that a large component of the alien flora is widespread in its distribution, and appears to be randomly distributed among most of the islands.  相似文献   
5.
The acetabular crease is a linear indentation located in the antero‐superior quadrant of the surface of the acetabulum at the level of the Byers Feature 17. Considered by palaeoanthropologists as a discrete trait, it has received scarce attention and the mechanisms underlying its formation and variations according to sex and age remain largely unclear. The purpose of this study, carried out on a large sample from a historic population in France, was to (i) analyse variations according to side, sex and estimated age at death; (ii) assess diachronic variations; and (iii) compare prevalence in various prehistoric and historic populations. Hip bones from a total of 425 subjects of both sexes and all ages were studied. Specimens were from two French historic samples dating from the 11th to 13th centuries and 16th to 17th centuries. The proportion of subjects that died young was higher in the 11th to 13th century group, but the prevalence of the acetabular crease was comparable between the two groups regardless of site or laterality (unilateral or bilateral). No sexual dimorphism or correlation with age was noted at either period. The acetabular crease appears to be a stable anatomical trait throughout adult life, with no predominant side and no correlation with sex. The significantly higher prevalence of the acetabular crease in some historic French samples and in prehistoric native Canadian populations could be linked to greater biomechanical stress during childhood in rural medieval populations and in the prehistoric period. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
6.
基于SEA的AGA-SVR节假日客流量预测方法研究   总被引:2,自引:0,他引:2  
节假日旅游客流量由于游客在短期内大量集中于同一地点、不同节假日休假时间长短、所处季节等不同,呈现复杂非线性特征和明显季节性特点.本文提出一种基于季节指数调整(Seasonal Exponential Adjustment,SEA)的自适应遗传算法(Adaptive Genetic Algorithm,AGA)-支持向量回归 (Support Vector Regression,SVR)预测模型,即基于SEA的AGA-SVR模型,并用国内著名5A级风景区黄山2008~2012年节假日客流量数据对模型进行验证.研究结果表明,基于SEA的AGA-SVR预测模型能够准确处理节假日旅游客流量预测中的非线性和季节性问题,较AGA-SVR和GA-SVR等方法具有更高的预测精度,在旅游预测领域应用前景广阔.  相似文献   
7.
为了对壁画颜料种类进行无损识别,根据不同的物质对光的吸收特性不同,决定着光谱反射率不同这一特性,提出一种基于可见光谱的颜料识别方法,并对敦煌壁画所用颜料进行了分析。提取可见光谱曲线二阶导数负数部分表征曲线峰值区域的几何轮廓,利用中值金字塔对提取结果进行三层分辨率表征以突出曲线峰值位置信息,归一化三种表征尺度并组合构建特征空间F,以欧氏距离为准则对壁画采样点与颜料库样本进行相似度判别,从而识别出壁画用颜料信息。结果表明,本研究构建的识别方法能够对壁画颜料种类进行无损识别,在壁画数字存档及修复领域具有一定的应用前景。  相似文献   
8.
王维国 《攀登》2005,24(4):129-130
唐宋古文运动是分别兴起于唐、宋时期的重要文学革新运动。它们的共同之处在于.都同当时的社会政治形势紧密相联;均打着复古的旗号为现实服务;文学观点比较接近,文学创作都取得了很高的成就。其相异之处在于,宋代古文运动有唐代古文运动作为借鉴,从而使宋人少走了许多弯路,使宋代古文创作在唐代的基础上取得了更加辉煌的成果。  相似文献   
9.
采用矿山考古、模拟实验等方法,对中国古代采矿技术的起源与发展进行系统论证后,得出三个论点:一是关于中国古代采矿工程技术的历史进程,可分为萌芽期(史前时期)、形成期(商代中期)、初步发展期(西周时期)、创新期(春秋至战国中期)、充实提高期(秦汉至元代)、全面发展期(明清时期)这六个发展阶段。二是中国古代采矿工程技术有着浓重的中国特色并具独特的发展体系,其多种技术的配合,在很大程度上基于中国古代各种社会要素的综合。三是中国古代采矿技术观是一种有机的、整体和综合的“和”的技术观,“和”明白地表述了采矿技术观的本质特征。  相似文献   
10.
Industrial land is under transition globally. Insights into this transition are important to plan a sustainable future. Since industrial land follows parcel shapes and the transition process requires multi-year data to observe the impacts of such changes, multi-year vector data should be used to analyse industrial land transition. This paper presents a framework to analyse path-dependent regional industrial land transition processes using vector data. A step by step instruction is presented. In the analysis, the changed percentages of land use in the surroundings of appeared or disappeared industrial land are visualized. The visualized surrounding land use compositions give planners an idea on what causes land use transitions, the most frequent transition forms and their impacts on the surroundings, purely from a land use point of view to reduce data collection efforts. The North Brabant region in the Netherlands is used as a case study. The region is split into urban and non-urban areas to show the generic applicability of this framework.  相似文献   
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