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基于关节臂和高清摄影进行重庆大足千手观音现状信息留取和精细三维重建具有现状的真实、完整记录,可为现场修复提供参考,为此,提出一种新的基于关节臂高精度扫描的文物精细三维信息获取方法,利用关节臂对文物进行扫描,获得高精度几何数据,在此基础上建立超精细三维建模,同时利用人工选取控制点来获取高分辨率影像。基于本方法所获得的精细三维信息可以用于三维统计、虚拟修复和变化检测等方面,为文物的现场保护修复工作提供科学依据,并为其他文物精细三维重建提供参考。最后以重庆大足石刻造像为例,验证了该方法的可行性与有效性。  相似文献   
13.
图们江地区物流长期预测研究的理论与方法   总被引:5,自引:2,他引:3  
本文运用路线比较模型与重力模型,对通过图们江地区的港口与相关路线的物流状况(2000~2020)进行了预测与研究,深入探讨了影响图们江地区物流的主要障碍因素,对不同障碍因素的变化及其对图们江地区物流的影响进行了分析。  相似文献   
14.
何光强  宋秀琚 《人文地理》2014,29(2):113-122
地缘政治分析离不开地图。在全球地缘政治分析中,作为世界地图基本空间框架的地图投影通过变形为人们架起了一座"认知的桥梁"--一种空间认知的视角,包括结构、中心方位、距离和面积四种认知。它们在人脑中组合成世界意象地图,为全球地缘政治分析营造了一个多维的空间思维条件。世界观念研究、地缘动态研究,地区研究和全球性问题研究都离不开全球地图投影。总之,地图投影对于国际关系研究具有重要价值。  相似文献   
15.
Abstract

The cordiform projection employed by Oronce Fine, Gerard Mercator and Abraham Ortelius may have had a hermetic meaning. The focus in this paper is on Ortelius, for recent studies have suggested connections between Ortelius, Christopher Plantin and a clandestine religious sect in Antwerp, called the Family of Love (Family of Charity), whose emblem was the heart, source of divine illumination and of Free Will. It is argued that Ortelius's contemporaries in the radical religious circles of northern Europe would have perceived the Theatrum orbis terrarum in such a light. As Guillaume Postel's evaluation of Ortelius's work demonstrates, the atlas was considered a talismanic book based on the power of the images.  相似文献   
16.
This paper estimates China’s future population and labour force by developing a novel forecasting model for population. It combines information about age-specific parameters on fertility and mortality for both rural and urban areas using information about rural–urban migration and the transformation of rural areas into urban ones. This model takes into account the effects of urbanisation on changes in the age structure of the Chinese population; and provides separate projections on the rural and urban populations. Our findings show that (i) the shares of people aged 65 and over, in China’s rural and urban populations, will double between 2010 and 2030; this implies that the ageing problem in rural areas will continue to be more serious than in urban areas; (ii) the rural labour force will shrink by 45 per cent, between 2010 and 2030, while the urban labour force will grow by 34 per cent; and (iii) China’s urbanisation rate will increase to 71 per cent by 2030.  相似文献   
17.
利玛窦与非欧氏几何在中国的传播   总被引:3,自引:0,他引:3  
明朝末年,利玛窦通过翻译《几何原本》将欧氏几何传人我国,同时,也通过各种活动传人了当时流行于欧洲的非欧氏几何。这些几何知识主要有圆锥曲线、平行正投影、球极投影、画法几何和透视法等。这些几何知识的传人,更加丰富了我国当时的数学研究,也更直接有力地促进了我国科学技术的发展。  相似文献   
18.
Using adjusted 2000 population census data, this paper conducts projections of China's population up to 2050. Three fertility and four mortality scenarios yield 12 sets of results. Even though fertility is below replacement, China's population will continue growing for many years. One of the notable trends is the rapid ageing of the population. By the end of 2050, one-fifth to one-third of China's population will be aged 65 and over. The demographic dividend is expected to continue in next 10 to 20 years depending on future fertility which, in turn, is determined by changes in China's one-child policy. The Chinese government should be aware of all possible situations of population change, and particularly population ageing in the first half of the century, and be well prepared for all possible challenges that may arise.  相似文献   
19.
ABSTRACT

This article reviews Alan Wilson's research on population and migration in the 1970s and the 2010s, which supplements his principal contribution - mathematical modelling of urban and regional systems. In the 1970s, drawing on input-output models of economies and working with Philip Rees, Wilson established the accounting basis for Andrei Rogers' multi-regional projection model, adding international migration. Innovative methods were developed to complete demographic accounts, where there were data gaps. In the 2010s, working with Adam Dennett, Wilson systematized methods for estimating migration flows between regions in Europe, employing his family of spatial interaction models. The key aim of both research strands was to ensure that no information was ignored to ensure consistency in population and migration models. The influence of Wilson's contributions to research on population and migration is traced through a survey of subsequent research.  相似文献   
20.
论文基于历年马来西亚官方的统计数据,对当前"少子化"背景下马来西亚华人人口发展现状进行系统描述;在人口转变理论框架下对马来西亚华人人口比重下降这一现象进行归因分析;并利用人口队列预测方法预测分析马来西亚中长期人口发展状况。研究发现:由于较早开始人口转变进程,马来西亚华人具有低生育率、高老龄化程度等特征;人口转变进程中的族群"堕距",是当前华人人口比重下降的根本原因。伴随马来西亚各族群人口转变进程的推进,未来华人人口比例下降速度将逐步趋缓,但老龄化程度将快速提高。  相似文献   
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