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131.
软科学与决策咨询研究 总被引:2,自引:0,他引:2
文章比较系统地分析了软科学的概念,提出了软科学研究现象,对探讨了软科学与决策咨询的关系,论述了决策咨询研究的现实意义,认为软科学是决策咨询的学科基础,软科学研究走向市场是大势所趋,而决策咨询是软科学研究成果市场化的基本形式,大力发展咨询产业是我国社会主义市场经济建设的重要组成部分。 相似文献
132.
旅游信息系统建设模式探讨——以佛山市为例 总被引:6,自引:0,他引:6
作为当前旅游信息系统开发的两种主要基础平台,地理信息系统和多媒体制作系统都存在一定的缺陷。多媒体制作系统缺乏旅游地图的有效管理,空间查询,分析和统计功能,旅游地理信息系统则缺乏旅游信息的多媒体表达能力。从实用性和普及性出发,集合二者优点开发模式具有更大的推广应用价值。因此,论文提出在同一界面下基于GIS和多媒体集成的旅游信息系统开发模式;(1)在GIS中增加多媒体信息表达能力,以关系数据库为核心,把多媒体文件名信息存储在地理信息系统属性库,依靠多媒休段实现多媒体数据与地理信息系统图形和属性的关联,实现查询的基本概念;(2)在多媒体系统中开发部分GIS空间查询功能。以此思路,佛山科技学院GIS技术实验室利用VB进行GIS和多媒体二次开发,成功地完成了佛山旅游信息系统的设计和开发。 相似文献
133.
134.
This is the second part of a contribution to the debate on the possibilities of leveraging economic globalisation — through incorporation in international production networks and global commodity chains (GCCs) — as a strategy for developing countries to industrialise and advance their position in the world economy. In the first part, we analysed the experience of the East Asian apparel industry and addressed the issues of sustaining positions, upgrading to more rewarding roles, and advancing to less dependent positions within production networks and GCCs. We developed an analytical framework at both the firm and industry levels, and subsequently identified alternative firm- and industry-level strategies and trajectories. The present paper deals with these issues in the context of the Singapore apparel industry. Based on extensive empirical research, we demonstrate that although the East Asian experience of upgrading and repositioning within the GCC is to some extent emulated in the case of the Singapore apparel industry, the outcomes have been less favourable in terms of the depth, extent and strength of these trajectories. The differing outcomes can be explained in terms of different (systemic) conditions in the Singapore business environment, including the agency of local players, the geography of sourcing networks, and the role of the state and prevailing business attitudes. Our conclusions merit continued attention in both research and policy circles on the development of capabilities at the firm level, and the role of local business and institutional environments in local industry development processes under globalisation. 相似文献
135.
Mordechai Haklay 《Area》2002,34(1):17-28
Public access to environmental information received much attention in the last decade. Recent developments promote access to this information through public telecommunication networks. This paper describes a Web-based survey that explored the requirements and needs of likely users of public environmental information systems for London: educated middle-class members of the public, with high interest in environmental issues and computer literacy. The survey demonstrated current information consumption patterns and the reasons to gather and use such information. 相似文献
136.
On the spatial relationship between landslides and causative factors on Lantau Island, Hong Kong 总被引:8,自引:0,他引:8
This paper presents a statistical approach to study the spatial relationship between landslides and their causative factors at the regional level. The approach is based on digital databases, and incorporates such methods as statistics, spatial pattern analysis, and interactive mapping. Firstly, the authors propose an object-oriented conceptual model for describing a landslide event, and a combined database of landslides and environmental factors is constructed by integrating the various databases within such a conceptual framework. The statistical histogram, spatial overlay, and dynamic mapping methods are linked together to interactively evaluate the spatial pattern of the relationship between landslides and their causative factors. A case study of an extreme event in 1993 on Lantau Island indicates that rainfall intensity and the migration of the center of the rainstorm greatly influence the occurrence of landslides on Lantau Island. A regional difference in the relationship between landslides and topography is identified. Most of the landslides in the middle and western parts of the island occurred on slopes with slope angles of 25–35°, while in the eastern part, the corresponding range is 30–35°. Overlaying landslide data with land cover reveals that a large number of landslides occurred in the bareland and shrub-covered area, and in the transition zones between different vegetation types. The proposed approach can be used not only to analyze the general characteristics of such a relationship, but also to depict its spatial distribution and variation, thereby providing a sound basis for regional landslide prediction. 相似文献
137.
One of the main factors that affects the performance of MLP neural networks trained using the backpropagation algorithm in mineral-potential mapping isthe paucity of deposit relative to barren training patterns. To overcome this problem, random noise is added to the original training patterns in order to create additional synthetic deposit training data. Experiments on the effect of the number of deposits available for training in the Kalgoorlie Terrane orogenic gold province show that both the classification performance of a trained network and the quality of the resultant prospectivity map increasesignificantly with increased numbers of deposit patterns. Experiments are conducted to determine the optimum amount of noise using both uniform and normally distributed random noise. Through the addition of noise to the original deposit training data, the number of deposit training patterns is increased from approximately 50 to 1000. The percentage of correct classifications significantly improves for the independent test set as well as for deposit patterns in the test set. For example, using ±40% uniform random noise, the test-set classification performance increases from 67.9% and 68.0% to 72.8% and 77.1% (for test-set overall and test-set deposit patterns, respectively). Indices for the quality of the resultant prospectivity map, (i.e. D/A, D × (D/A), where D is the percentage of deposits and A is the percentage of the total area for the highest prospectivity map-class, and area under an ROC curve) also increase from 8.2, 105, 0.79 to 17.9, 226, 0.87, respectively. Increasing the size of the training-stop data set results in a further increase in classification performance to 73.5%, 77.4%, 14.7, 296, 0.87 for test-set overall and test-set deposit patterns, D/A, D × (D/A), and area under the ROC curve, respectively. 相似文献
138.
Use of GIS layers, in which the cell values represent fuzzy membership variables, is an effective method of combining subjective geological knowledge with empirical data in a neural network approach to mineral-prospectivity mapping. In this study, multilayer perceptron (MLP), neural networks are used to combine up to 17 regional exploration variables to predict the potential for orogenic gold deposits in the form of prospectivity maps in the Archean Kalgoorlie Terrane of Western Australia. Two types of fuzzy membership layers are used. In the first type of layer, the statistical relationships between known gold deposits and variables in the GIS thematic layer are used to determine fuzzy membership values. For example, GIS layers depicting solid geology and rock-type combinations of categorical data at the nearest lithological boundary for each cell are converted to fuzzy membership layers representing favorable lithologies and favorable lithological boundaries, respectively. This type of fuzzy-membership input is a useful alternative to the 1-of-N coding used for categorical inputs, particularly if there are a large number of classes. Rheological contrast at lithological boundaries is modeled using a second type of fuzzy membership layer, in which the assignment of fuzzy membership value, although based on geological field data, is subjective. The methods used here could be applied to a large range of subjective data (e.g., favorability of tectonic environment, host stratigraphy, or reactivation along major faults) currently used in regional exploration programs, but which normally would not be included as inputs in an empirical neural network approach. 相似文献
139.
信息产业发展对宁波城市内部结构的影响 总被引:2,自引:1,他引:2
王益澄 《地理与地理信息科学》2003,19(3):80-83
该文从信息产业的概念和分类人手,着重分析信息产业发展对城市产业结构、社会结构和空间结构的影响。对宁波市信息产业与城市产业结构的内在关系进行了量化研究;探讨信息产业对城市内部社会结构分异的变化趋势;提出了信息产业对城市内部空间结构功能置换的两种模式和地域扩张的促动机制。 相似文献
140.
基于网格的空间信息模型与服务技术研究 总被引:12,自引:0,他引:12
空间信息基础设施是实现数字城市的核心与基础,现有的万维网已经不能满足空间信息访问与处理的需要。该文对以空间信息为核心和基础的数据网格——空间信息网格的基础理论及网格中的空间信息模型与服务技术:进行研究。提出了空间信息网格的若干关键技术及网格中的空间信息模型的特点与要求,并对空间信息网格服务进行了初步的探讨。 相似文献