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991.
通过利用喀什市研究区2012年的资源三号卫星影像,使用ERDAS软件首先提取归一化植被指数(NDVI),再使用Arc GIS软件对研究区的植被覆盖度进行估算,最后得出研究区2012年的植被覆盖度分级图,定量地说明了研究区2012年的植被覆盖情况。  相似文献   
992.
采用1 500℃高温熔融水淬制得K2O-(n-x) B2O3-xSiO2玻璃粉,掺入Al2O3陶瓷填充料来制备K2O-(n-x)B2O3xSiO2/Al2O3低温共烧陶瓷介质材料.系统研究了玻璃基中SiO2/B2O3比例变化和玻璃掺入量对玻璃/陶瓷材料结构和性能的影响规律.研究结果表明,B2O3含量增加抑制了玻璃Y中SiO2析晶,使复合材料的介电常数、介电损耗在一定程度上有所减小,复合材料的抗弯强度也有一定程度的减小.  相似文献   
993.
RD资源的投入是企业实现产业升级的重要保障,但关键是RD资源投入多少合适和各企业RD投入的标杆水平如何确定。文章作者将标杆管理运用于RD的资源配置领域,通过建模、评价、及测度分析,确立了最适合企业发展的RD投资的标杆水平,从而为企业在充分利用稀缺资源时,如何达到资源效用最大化,提供了一个学习的标杆。文章以上市公司制造类企业为例,首先构建了评价RD投资标杆水平的模型,进而通过结构方程模型对之进行了测度分析,找出了各行业RD资源投入的标杆水平,最后再进一步利用特征偏离法测算出各企业RD资源投入现状距离标杆水平的差距。  相似文献   
994.
A recent study of R&D alliances between new biotechnology firms (NBFs) and pharmaceutical firms investigated how NBFs deal with the “swimming with sharks” dilemma involved in allying with firms capable of appropriating value. It concludes that NBFs are less likely to select alliance partners with related expertise because of greater appropriation risk. Based on our experience as NBF managers and a survey of NBF executives, we believe that such situations are uncommon, and that the study more likely shows pharmaceutical firms seeking diversification. Thousands of NBFs seek alliances with the top 100 pharmaceutical firms, and the larger company is much more likely to be the one to select among multiple potential partners. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
995.
The sequence of events leading up to the upcoming auction of 1800 MHz spectrum in India has led to the auctions acquiring an extraordinary significance for the future of the Indian mobile industry. A key feature of the auction design proposed by the regulator TRAI is the benchmarking of the reserve price of 1800 MHz to the price of 2100 – 3G spectrum revealed in the 2010 auction. In the context of the low number of LTE devices available and the fragmentation in the 1800 MHz band, this paper proposes reducing the duration of spectrum holding to ten years (from the current level of twenty years), and calibrating the reserve price of 1800 MHz with its value with GSM deployment. An economic model is used to compute the value of startup and incremental 1800 MHz spectrum. The estimated values are shown to differ from the value of 2100 MHz spectrum at a pan-India level and also in their distribution across circles. A new set of reserve prices are computed based on the estimation. The estimated values are also shown to be close to the AGR-adjusted price revealed in the 2001 auction. A reserve price based on the 2001 auction is also provided. Concomitant features of the auction are suggested to give coherence to the auction design.  相似文献   
996.
We propose a semi-cooperative game theoretic approach to check whether a given coalition is stable in a Bayesian game with independent private values. The ex ante expected utilities of coalitions, at an incentive compatible (noncooperative) coalitional equilibrium, describe a (cooperative) partition form game. A coalition is core-stable if the core of a suitable characteristic function, derived from the partition form game, is not empty. As an application, we study collusion in auctions in which the bidders? final utility possibly depends on the winner?s identity. We show that such direct externalities offer a possible explanation for cartels? structures (not) observed in practice.  相似文献   
997.
This study assesses whether the sale method in residential real estate markets – auction versus private treaty – is a determinant of sale price. Utilising a larger and richer dataset than previous research, we test for a price effect in auction sales in Sydney and Christchurch. When self‐selection biases are corrected for, using two‐stage hedonic regression analysis and a matched sampling procedure, we find no significant difference between prices of properties sold at auction to those sold by private treaty. This conflicts with the conclusions of previous research in the Australian and New Zealand housing markets, which have documented a price premium associated with auction sales.  相似文献   
998.
In the present paper, we propose an extension of Spengler's (1950) analysis of successive oligopolies, to study the effects of entry in the downstream and upstream markets. Free entry is analyzed using replica economies à la Debreu and Scarf (1963) . We find that free entry may have different effects in the upstream and in the downstream market. Namely, the usual convergence of the price to the corresponding marginal cost only occurs in the downstream market.  相似文献   
999.
This paper examines the role of external service linkages in the innovation and market peformance of small manufacturing firms (SMFs). Survey data from a technological cross-section of 146 Western New York SMFs are summarized. The data suggest a helpful role for consultants in the product development efforts of innovative firms, especially those that serve foreign export markets. Several multiple discriminant models are presented, each of which suggests an interactive connection between SMF commercial performance, externa) technical links, innovation propensity and in-house R&D. It is argued that innovative SMFs that exploit specialized technical services perform significantly better than comparably sized firms that rely solely on in-house resources. It is also argued that the quality of a region's producer service environment may have a significant bearing on the growth potential of its SMF population. The paper concludes by discussing the main academic and public policy implications that flow from the empirical results.  相似文献   
1000.
La definición estadística «estándar» de desempleo suele criticarse porque excluye a muchas personas, consideradas ocupadas o inactivas, cuya situación es comparable en realidad a la de desempleo. El autor analiza los problemas metodológicos y estadísticos asociados a esta definición, así como su inadecuación a los países en desarrollo, donde el empleo es muy heterogéneo. Demuestra además que la tasa de desempleo tiende a subestimar el excedente de oferta de mano de obra y es un mal indicador del déficit de trabajo decente. Por último, destaca sus límites en tanto que orientador de la política económica.  相似文献   
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