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851.
以浙江省为例,基于区位熵方法借助从业人员数据刻画文化创意产业空间格局,并运用主成分分析法与OLS模型,甄别驱动因素佐证文化创意产业区位模型。结果表明:① 市域尺度浙江文化创意产业区位规律不仅具有“资本空间”(杭州)集聚性,还具有“地方空间”(舟山、金华和台州)分异性;② 经济科教、政府支持、市场需求、环境、交通和地方性是重要区位因素,且不同重点行业、不同地理层级所受区位因素不尽相同;③ 浙江文化创意产业全行业区位特征主要是基础设施和管治双要素驱动型,8重点行业区位特征主要是“软因子”驱动型;④ 研究有助于提升城市文化创意产业政策着力点与规划调控协同性。 相似文献
852.
Mobile internet and wireless communication technologies have produced unprecedented location-aware data. Such big geospatial data can be used as a proxy measure of the ‘digital footprints' left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine scales. This study investigated the spatiotemporal variations of human's digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent's location request data. The results showed that human's digital footprints cover less than 5% of Qinghai and Tibet, exhibiting either a U-shaped or an N-shaped temporal change pattern during the major festivals. Spatial changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and Lhasa. Human disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6% of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59, and the disturbance was significantly escalated during the National Day holiday. By contrast, the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1% and 0.1, respectively. 相似文献
853.
针对岩石力学试验声发射时差定位算法中时延估计精度受诸多不确定因素的影响问题,提出全相位相位差法时延估计,通过小波分解与全相位频谱分析相结合求解相位差得到声发射信号的时延估计。利用小波分解找到不同传感器接收到的声发射信号中的同一主频的子带信号;对这些同一主频的子带信号分别做全相位频谱分析,得到每个子带信号中间样点的相位,再根据相位差与时间差的关系求出声发射信号到达不同传感器之间的时间差;进而利用时差定位法反演声发射源,实现了声发射源更精确的定位。在花岗岩(50 mm×100 mm×50 mm)上进行断铅试验,选取10个测点,经声发射监测验证结果表明,该时延估计方法能有效地减小声发射源定位的误差,提高声发射源的定位精度,平均绝对误差比美国PCI-2型声发射仪器定位结果提高约3 mm,该方法为反演声发射源提供了一种有效途径。 相似文献
854.
企业海外集群与新晋企业对外直接投资区位选择——基于浙江省微观企业数据 总被引:1,自引:2,他引:1
企业对外直接投资海外集群和区位选择均是当前理论和政策的热门话题,着眼于研究两者之间的关系。由于东道国国别经济存在较大的差异,因此中国企业在对外直接投资区位选择过程中较为注重特定的国别状况,东道国经济规模、人均收入、贸易开放、资源条件等因素均构成了企业对外直接投资区位选择的影响因素,此外本国企业在东道国的海外集群也是企业对外直接投资区位选择决策的不可忽视因素。利用浙江省微观企业数据构造二值选择模型,并使用浙江省在某东道国的对外直接投资项目数度量在该国的海外集群状况,研究发现:企业海外集群是东道国吸引新晋企业对外直接投资的重要区位优势,并且这种区位优势在资源越丰富和市场规模越大的国家发挥的作用也越大。为了消除回归的内生性问题,使用地理距离作为企业海外集群的工具变量,通过二阶段二值选择模型得出了类似的结论;并且通过分样本实证研究发现无论在发达国家还是发展中国家东道国,企业海外集群吸引新晋企业对外直接投资的正向影响均保持不变。结果说明了企业对外直接投资海外集群具有自我延续性,也反映了信息在企业对外直接投资区位选择中的重要性。 相似文献
855.
粤港澳大湾区城市群作为世界四大湾区城市群之一,在国家发展格局中占有重要的地位。基于多源数据,利用重心迁移模型、扩张演化模型及改进的引力模型探究近20年粤港澳大湾区城市群的演化。结果表明:①在城市演化类型上,澳门、肇庆呈单向型演化,佛山、中山、珠海、惠州、香港呈双向型演化,广州、江门、东莞、深圳呈发散型演化;2008~2017年城市群整体的扩张速度与强度低于1998~2008年。②近20年粤港澳大湾区城市群的城市质量、关联度呈不断上升趋势,并表现出一定的区域性和不平衡性,城市质量与经济发展程度、城市空间呈正相关关系,城市质量高的城市与周边城市的关联度高;③粤港澳大湾区城市群的社会经济区位度存在明显“断层”,缺乏合理的梯度等级,并表现出一定的空间分异且部分城市的区位度演化显著。 相似文献
856.
857.
产业集群的辨识及其特征分析——以浙江省制造业为例 总被引:4,自引:0,他引:4
产业集群是国内非常重要的经济现象, 但是如何辨识产业集群却一直困扰着学术界和政 府部门, 关键问题是产业集群缺乏统一的辨识标准。浙江省拥有数量众多的制造业产业集群, 而 且涉及的产业门类非常广泛, 是我国产业集群发展最为典型的省份之一。本文利用2001 年浙江 省基本单位普查数据, 同时选取浙江省各个邮区的四位数产业就业区位商≥3 以及该产业内的 企业数目≥100 家这两个标准, 进行产业集群的辨识, 共辨识了116 个典型产业集群。结果表明, 按照该辨识标准, 能够辨识出典型的制造业产业集群, 而且每个产业集群都具有明确的产业门类 及地理边界。文章最后部分归纳了浙江省典型制造业集群的空间分布以及规模结构等特征。 相似文献
858.
This paper highlights three major aspects of gender differences in employment in Haifa, Israel (1972 and 1983): commuting distance, place of residence, and employment location. In 1972 working womenaposs residences were more central-city-oriented, whereas in 1983 they were more suburbanized. Commuting distances increased between 1972 and 1983 for both sexes, but more for men than for women. This shorter “female'’distance is related to the location of employment and its occupational segregation. The lower commuting values in Haifa compared to other places relate to the size, housing patterns, and structure of the study area, and to its levels of suburbanization and automobile ownership. 相似文献
859.
At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right
can be transferred and land users must pay the rent to the state according to the quality of land. It is necessary to apply
the theory of rent and location to the economic approaisal of urban land.
China is vast in territory. Is’s geographical condition and economic development vary from place to place, so does the urban
land value. In order to reveal the difference of land value between different cities, the following method is used. (1) Analysing
the factors and elements that affect the quality of urban land. Six factors including 17 elements were selected in this paper:
macrolocation of a city, benefit of urban aggregation, infrastructure investment, output value of urban land, potential of
urban land, and investment intensity. (2) Deciding the weight andvalue of each factor. (3) Appraising each element separately.
(4) Accounting the value of all factors and getting the total appraisal score of each city. (5) Grouping the 430 Chinese cities
into sevencategories according to the appraisal values.
The result shows that all the cities in the category with the highest land output values are in the coast belt, whereas most
cities in the inland and outlying areas are belong to the category with low rank. For example, 87% of the cities in the outlying
regions are belong to the lowest rank. Although there are some relationship between the size of cities and urban land rank,
generally speaking, the larger the city, the higher the urban land rank. In fact, the locational condition is the most important
factor which influences the rank of urban land. 相似文献
860.
祝卓 《中国地理科学(英文版)》1991,1(2):129-140
Cotton is the leading cash crop in China. The cotton sown area accounts for about 30per cent of the total sown area of all the various cash crops. It is the main material used in the textile industry in China. More than 95per cent of textile materials were cotton during the 1950s; and it still occupies 80per cent at present. There are some problems concerning rational location of cotton production in China. In order to solve the problems existing in civil cotton production and supply, in view of strategy, a number of cotton production bases must be selected and built step by step in a planned way. The location of cotton production should be adjusted progressively in accordance with the existing problems. The existing cotton production regions should be consolidated and improved. The cotton production region of the middle and lower reaches of the Huanghe River should be renewed quichly to make it become the largest stable and high-yield cotton preduction region. In the regions with suitable natural condi 相似文献