• 黄河流域城市创新能力测度及空间分异研究

    Subjects: Geosciences >> Geography submitted time 2024-05-20 Cooperative journals: 《干旱区地理》

    Abstract:创新在全国现代化建设全局中占据核心地位,城市是创新活动开展的主体区域,科学测度城市创新能力对于提升城市竞争力及制定创新战略具有重要价值。以黄河流经区域中的48个城市作为研究对象,从人才培养能力、科技研发能力、经济支撑能力和环境服务能力4个维度构建了城市创新评价指标体系,运用熵权法、Jenks Natural Breaks分类法、基尼系数、Moran’s I 等数据分析方法,测度了黄河流域城市创新能力,分析了黄河流域城市创新水平的空间分异及主要障碍因素。结果表明:(1)黄河流域整体创新能力不高,少数高值城市与其余城市之间得分差距显著,创新能力呈现上、中、下游阶梯式递增趋势。(2)以朔州—陇南为线,城市创新能力呈现出东南高西北低的分布状态,且各维度的空间分布与总创新能力趋于一致。(3)黄河流域城市创新能力分布处于较不均衡状态,空间集聚特征表现为正向的空间关联,主要属于低值集聚的空间模式。(4)科技研发能力与人才培养能力对黄河流域城市创新能力的提高影响程度较大,其中有效发明数是各城市共同的障碍指标。

  • A minimum-envy location problem for spatial equality of public service: model formulation and case analysis

    Subjects: Geosciences >> Geography Subjects: Mathematics >> Control and Optimization. submitted time 2023-05-13

    Abstract: Location problems have been widely applied to service planning of public health, compulsory education, emergency management, and delivery logistics. However, the mainstream location models are usually to optimize the efficiency objectives such as travel cost, facility cost and the number of customs to be served, rather than the equality objectives. A few location models aim to optimize one of the equality measures, such as the variance of distances, the deviation of distances, the Gini coefficient between the travel distances, and the variance of spatial accessibility indexes. However, the facility locations, capacities and their service areas can be easily distorted by most equality-oriented objective functions. In this paper, a spatially envy objective function for service equality is proposed to overcome the shortcomings of commonly used equality functions. The envy value of customers at a location is determined by their travel distance that beyond a predefined distance. The envy function can be added to mainstream location models in a weighted manner. As a result, the capacitated p-median problem (CPMP) is enhanced as CPMP-envy. The original and improved models were tested on three large instances. Case experiments show that the equality measures, such as maximum travel distance, variance of distances, coefficient of variation, and Gini coefficient between travel distances, can be substantially improved by minimizing the weighted sum of spatial envy and travel cost. It is argued that the envy indicator has theoretical and practical potentials in facility planning towards spatial equality of public service.

  • Research on Evolution of Yellow River Basin Innovation Network and Cultivation of Zhengzhou-Luoyang-Xi’an Innovation Corridor

    Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》

    Abstract: Constructing innovation networks and cultivating innovation corridors are important to realize regional innovation development. Based on the data of patent transfer from 1987 to 2018, this paper analyzes the spatial-temporal evolution of technology transfer network at different scales in the Yellow River Basin, and proposes the cultivation path of Zhengzhou-Luoyang-Xi’an innovation corridor. Firstly, it is found that a majority of technology transfer within the basin is switching from inter-provincial transfer to intra-provincial transfer, with provincial capitals being the main source of technology. Xi’an is the primary source of technology transfer network, and cities, such as Zhengzhou, Qingdao, and Jinan, are secondary sources. Moreover, the technology sources outside the Yellow River Basin are mainly located in the Beijing-Tianjin-Hebei, Yangtze River Delta, Pearl River Delta and other developed urban agglomerations. In addition, Xi’an, Jinan, Qingdao and other high-level central cities have become the main receiving areas of technology transfer. This study concludes that the construction of inter-provincial innovation network should focus on the construction of Zhengzhou-Luoyang-Xi’an innovation corridor, in order to realize the matching and coordination of industrial technological advantages and technological demands of different cities, promote the construction of Zhengzhou-Luoyang-Xi’an high-quality development cooperation belt, and then accelerate the innovation-driven development process of the Yellow River Basin.

  • 塔里木盆地西南缘表土碳同位素组成特征分析

    Subjects: Geosciences >> Geography submitted time 2023-02-02 Cooperative journals: 《干旱区地理》

    Abstract:土壤碳同位素可以反映生长植被的同位素组成,从而进一步反映当时的植被类型以及气候环境状况。已有的研究显示,不同地区碳同位素与气候因子的关系存在显著差异,因此在不同区域开展土壤碳同位素与气候因子之间相关性关系分析对古气候的重建至关重要。通过采集塔里木盆地西缘帕米尔地区和盆地南缘和田地区策勒县的表土沉积物,分析测定后获得其有机碳同位素,并将该表土有机碳同位素数据与气候因子进行相关性分析,以探明研究区有机碳同位素组成特征及其潜在的气候意义。结果表明:帕米尔地区和策勒地区的表土碳同位素变化对气候因子的响应存在明显差异。气温方面,帕米尔地区与气温呈正相关,其中与冷季气温相关性最好(r=0.598,P 碳同位素来重建古气候时应充分考虑区域差异的影响。