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991.
作为推动国民经济增长和促进社会稳定的基础力量,中小企业在市场中扮演着最活跃的经济主体。与大企业相比,中小企业有其鲜明的成长特征,从动态演进视角选取体量规模、生命周期、要素需求三个维度,系统探讨了中小企业的差异化特征。结论显示:体量规模特征反映在个体与群体以及经济板块之间;生命周期特征体现在死亡陷阱和空间格局演变上;要素需求特征会根据阶段创新内容的不同做出适时调整。  相似文献   
992.
[目的]确定农村集体商服用地、工业用地价格的影响因素,为科学评估农村集体经营性建设用地地价、构建城乡统一建设用地市场提供参考。[方法]利用全国农村土地使用制度改革试点之一的江西省余江县179个交易案例,运用特征价格模型分析农村集体商服用地、工业用地价格的影响因素及各类因素的贡献率。[结果](1)农村集体商服用地价格的主要影响因素依次为乡镇财政收入、人均纯收入、到客运站距离、到国道的距离、教育设施;农村集体工业用地价格的主要影响因素依次为人均纯收入、人均农村居民点面积、到客运站的距离、到国道的距离。(2)社会经济因素、区位交通因素和公共设施因素对集体商服用地价格的贡献度分别为69. 0%、20. 4%和10. 6%;社会经济因素和区位交通因素对集体工业用地价格的贡献度分别为52. 8%和47. 2%。[结论]总体上与国有城镇建设用地价格存在共性规律,但存在部分因素与国有建设用地价格规律存在差异,农村集体经营性建设用地估价不宜完全套用城镇建设用地的思路。  相似文献   
993.
土地是最基础与最重要的资源与资产,是国家经济政策拟定的依据,是实施规划纲要与落实方针政策的基础。土地是人类生存的基础,而且是不可再生的,只有加大土地管理的力度,高效合理地利用土地,才能实现我国可持续发展的目标。地籍管理是土地管理工作的重点领域,是土地产权得到保障的前提。目前的土地管理集中在对土地产权的管理,土地产权变化会涉及到地理实体时间、空间及属性的变化,时态GIS正好反映了此变化。目前时态GIS的研究集中在对时空数据模型的建构。时空数据模型决定了时态GIS系统的运行效率。无论是国内还是国外均对时空数据模型进行了研究,通过模型的构建的相应地提出了超过20种模型,而在实际的应用中,不同的模型有不同的特点。文章对典型的6种时空数据模型进行了分析,从模型的建模思路出发,分别探讨了模型的适合环境与优缺点,可以为人们在应用时空数据模型进行土地管理时提供帮助,有利于研究者对模型的进一步研究。  相似文献   
994.
生态红线划定是城市可持续发展的基础,目前的生态红线划定主要采用国家生态红线划分标准来进行,没有考虑与城市建设用地空间的相互协调,为了解决这一问题,以多智能体系统理论为基础构建"城市建设用地—生态保护红线"协调的决策模型,协调城市建设发展与生态环境保护的现实需要,确定不同保护和发展模式下的城市生态红线。以鄂州市作为研究区域进行实验,模拟了不同生态保护模式下的生态保护红线划定情况,结果表明在生态红线划定中考虑多主体的决策因素有助于协调优化城市生态环境保护与城市发展的矛盾。  相似文献   
995.
We examine the impact of typhoons on local economic activity in coastal China. To capture potential damages from an individual typhoon we use historical typhoon track data in conjunction with a detailed wind-field model. We then combine our damage proxy with satellite derived nightlight intensity data to construct a panel data set that allows us to estimate the impact of typhoons at a spatially highly disaggregated level (approx. 1 km). Our results show that typhoons have a negative and significant, but short-term, impact on local activity – a typhoon that is estimated to destroy 50% of the property reduces local economic activity by 20% for that year. Over our period of analysis (1992–2010) total net economic losses are estimated to be in the region of $US 28.34 billion. To assess the damage risk from future typhoons we use simulated probability distributions of typhoon occurrence and intensity and combine these with our estimated effects. Results suggest that expected annual losses are likely to be around $US 0.54 billion.  相似文献   
996.
This paper analyzes the main determinants influencing environmental innovators (i.e. firms developing or adopting environmental innovations) in Spain with respect to non‐environmental innovators. Similarly to other contributions in the literature, our results show that Spanish environmental innovators respond to regulatory stimulus in the form of demand‐pull and technology‐push instruments. They have a high internal technological capability and combine internal and external information sources, mostly in cooperation with knowledge institutions. Environmental innovators are more concentrated in mature, traditionally highly polluting sectors, but new firms are not more environmentally innovative than incumbents. Most importantly, in contrast to other environmental innovation studies, mostly carried out in a German context, we have not found evidence of a market pull from either the domestic or international markets. Furthermore, cost savings are not found to be a distinctive driver for environmental innovators. These differential results are possibly related to the special features of Spain regarding its national innovation system and the degree of stringency of environmental regulation and environmental consciousness of its consumers. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
997.
This article extends earlier efforts at redating the US industrial cycles for the prewar period (1890–1938) using the methodologies proposed by Bry and Boschan (1971) and Hamilton (1989) and based on the monthly industrial production index constructed by Miron and Romer (1990) and modified by Romer (1994). The alternative chronology detects 90% of the peaks and troughs identified by the NBER and Romer (1994), but the new dates are consistently dated earlier for more than 50% of them, especially as regards the NBER troughs. The new dates affect the comparison of the average duration of recessions and expansions in both pre-WWI and interwar eras. Whereas the NBER reference dates show an increase in average duration of the expansions between the pre-WWI and interwar periods, the new dates show evidence of shortened length of expansions. However, the new dates confirm the traditional finding that contractions lasted longer in the post-war period than during the pre-war period.  相似文献   
998.
我国农村集体建设用地空间布局混乱,而现有关于农村集体建设用地空间研究方面存在理论与方法缺陷。文章对农村集体建设用地空间格局及机制、农村集体建设用地的空间优化、城乡建设用地统一空间研究领域相关研究进展进行综述,结论为现有研究存在理论体系尚未建立、研究内容不健全、研究方法以定性描述和空间描述为主等问题。建议未来该领域研究应跳出传统土地管理相关理论,多学科交叉,探索地理学、经济学在农村集体建设用地空间研究方面的理论框架;基于空间格局—演变机制—优化配置的思路,构建农村集体建设用地空间格局演变动力模型、农村集体建设用地空间与人口/产业的相互影响模型、城乡建设用地统一空间模型,从农村集体建设用地空间格局及其演变机制、农村集体建设用地空间与人口/产业的协调机制、城乡联系机制下的农村集体建设用地空间优化3方面来开展农村集体建设用地空间研究。  相似文献   
999.
Agricultural applications of nanotechnology are at a relatively early stage and little is known about consumer responses to the technology. Canadian consumer responses to food nanotechnology are examined through the lens of the Food Value Scale. Data from a survey of Canadian consumers are used to evaluate the relative importance of eleven food values to food purchase decisions. We find that taste, safety, nutrition, and price are among the most important food values to Canadians, however, consumers exhibit considerable heterogeneity with respect to the priority placed on these values. A discrete choice experiment (DCE) explores the effect of food values on choice behavior. The DCE is positioned as a sliced apple product with non-browning and antioxidant-enhanced features introduced through the use of nanocoating or a conventional coating method. Random parameters logit (RPL) and latent class models (LCM) confirm the existence of significant preference heterogeneity. The LCM identifies three classes of consumers: “supporters,” “doubters,” and “opponents” who differ in their reaction to nanotechnology and in the relative importance placed on food values such as naturalness, novelty, and convenience. The analysis shows that food values provide additional insights into consumers’ food choices and their attitudes toward novel food technologies.  相似文献   
1000.
Forest ecosystems deliver valuable services to humanity. However, many forests are being degraded and their services have been undervalued. The main problem lies in the inadequate institutional arrangements for forest governance. This paper aims to assess the effects of alternative forest governance arrangements on the provision and economic values of forest ecosystem services (FES) in Vietnam. The study presents a framework for mapping land use and land cover (LULC) change stemming from actual and hypothetical changes in forest governance regimes, quantifies the resulting changes in the provision of FES, and estimates the associated economic values. In the context of the study site in the North Western uplands of Vietnam, we test three alternative forest governance scenarios: business as usual, with a dominant government role; a community-based governance regime; and a private, individual-based forestry governance regime. Scenarios are based quite closely on the way these regimes are (or might be expected to be) implemented in Vietnam. For each forest governance scenario, we map LULC changes based on land suitability analysis and transition likelihood for the period 2010 − 2020. The resulting maps are used as inputs into the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) model, which is used to estimate the quantity of three specific FES: carbon storage/sequestration, sediment yield, and water yield. We apply economic valuation methods to value these services: the social cost of carbon is used to estimate the economic values of carbon storage/sequestration; the cost of removing sediment deposited in reservoirs is applied for valuing the reduction of sediment yield, and the residual value of water supply for hydropower generation is used for valuing water yield. The results show that forest governance regimes have a significant effect not only on forest LULC, but also on the quantity and values of FES derived from forests. The FES are differentially affected by alternative forest governance regimes: some FES increase in quantity and value under some governance regimes and decrease under others. Of the three forest governance regimes examined, there is no one regime that will always be ‘better’ than the others in terms of provisioning all considered FES. For the specific context of Vietnam, we find that the private forest governance scenario is inferior to the community-based governance scenario, as an alternative to the current state-based governance. Because our results pertain to the scenarios as constructed, rather than generally to broad categories of governance regimes, there remains the possibility that regimes can be constructed that outperform all of those examined here.  相似文献   
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