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151.
In this paper we compare conceptualising single factor technical and allocative efficiency as indicators of a single latent variable, or as separate observed variables. In the former case, the impacts on both efficiency types are analysed by means of structural equation modeling (SEM), in the latter by seemingly unrelated regression (SUR). We compare estimation results of the two approaches based on a dataset on single factor irrigation water use efficiency obtained from a survey of 360 farmers in the Guanzhong Plain, China. The main methodological findings are that SEM allows identification of the most important dimension of irrigation water efficiency (technical efficiency) via comparison of their factor scores and reliability. Moreover, it reduces multicollinearity and attenuation bias. It thus is preferable to SUR. The SEM estimates show that perception of water scarcity is the most important positive determinant of both types of efficiency, followed by irrigation infrastructure, income and water price. Furthermore, there is a strong negative reverse effect from efficiency on perception. 相似文献
152.
自来水经过一定的处理工艺,然后经过配送管网输送至各户。水在配送管网中流动的过程中,往往会受到管网、供水管道及附属设备的影响,造成二次污染。因此,要切实做好城市供水二次污染的防治工作,提高人们的生活质量。基于此,本文提出了城市供水二次污染的几点原因和一般性的治理对策。 相似文献
153.
Michael Heller 《Business History》2016,58(7):1034-1054
In the 1930s, the General Post Office (GPO) in Britain became one of the nation’s most innovative pioneers of marketing communication. Following criticism of the organisation in the 1920s for its conservative use of publicity, the GPO embarked upon a series of creative publicity campaigns that applied, amongst other methods, advertising, public relations, promotions, cinema, events and artistic posters. Through an overview of its publicity, and through a narrative of three case-studies, this article argues that one of the most important innovations of the GPO was its integration of marketing communication, both in terms of techniques used and in relation to its emphasis in promoting the organisation and the services it provided. 相似文献
154.
从企业孵化网络本身以及环境视角分析了企业孵化网络治理绩效的影响因素,通过企业孵化网络治理机制对治理绩效关系的实证分析,验证了环境不确定下企业孵化网络的契约治理机制、管理治理机制对治理绩效的影响。结果表明:企业孵化网络治理机制中的契约治理机制、关系治理机制对治理绩效具有正向调节作用;环境不确定性会扩大或缩小治理机制对治理绩效的作用强度。企业孵化网络在高市场不确定性环境下,采用关系治理机制的绩效较好;在高技术不确定性环境下,采用契约治理机制的绩效较好。 相似文献
155.
Demand projections for civil aviation have forecast increases in operations in future decades. Increases in demand are beneficial to the growth and advancement of the aviation industry, but also come with the threat of significant increase in environmental impacts. In response, the industry is focusing on programs to develop technologies for reductions in fuel burn, NOx emissions, and noise. While aircraft-level impacts are an obvious metric of success, it is difficult to make informed robust technology investment decisions with respect to noise without understanding the fleet-level impacts. Fleet-level predictions of noise for technology explorations are especially complicated because it is computationally expensive, highly combinatorial, and airport-specific. Recently, rapid automated airport noise models have been developed, which can be simulated using Design of Experiments (DOE). The results of these simulations are used to generate surrogate models for airport noise contour area, which can be summed to yield a fleet-level impact. These models make use of simplifying assumptions to provide estimates of airport-level noise that are substantially cheaper to compute. They can be used to perform parametric trade-off analyses in conjunction with the equivalency assumption. Equivalency asserts that environmental impacts of a technology infused aircraft can be represented by scaled operations of the baseline aircraft in the same class. This simple assumption allows for the modeling of technology and market penetration factors under the same units: operations. This research uses surrogate models in conjunction with the equivalency assumption to examine two potential technology scenarios in a target forecast year, simulating technology and market performance factors to identify vehicle classes that could have the greatest impact in reducing contour area. Results show that technology and market performance of future notional Small Single Aisle and Large Single Aisle vehicle aircraft have the highest positive correlations with potential reductions in contour area. 相似文献
156.
Although productivity spillovers have long been recognized to be a major benefit of foreign direct investment (FDI), such spillovers have not yet been systematically studied in the context of the hotel industry. This paper investigates hotel-related FDI spillover effects as well as moderating factors (geographic region, star rating classification, ownership type and foreign capital origin) in China. Evidence from province-level panel data reveals the existence and significance of intra-industry spillovers from foreign to domestic hotels in China, although the nature and magnitude vary based on different moderating factors. Domestic hotels in eastern and western China and those with alliance and limited liability ownership structures benefit significantly from productivity spillovers. Foreign-invested three-star hotels transfer a significant amount of positive productivity, whereas domestic three- and five-star hotels benefit the most from productivity spillovers. Moreover, foreign-invested hotels from Hong Kong, Macau, and Taiwan (HMT) and non-HMT countries generate positive spillovers of similar magnitudes. 相似文献
158.
基于高层梯队理论,利用深圳证券交易所2008-2014年上市企业的数据,探讨了女性高管参与对企业R&D投入的影响,以及所有权性质的调节作用。研究结果显示:女性高管参与对企业R&D投入二者之间呈现出显著的负相关关系;民营企业的所有权性质将显著调节女性高管参与对R&D投入的抑制效应。 相似文献
159.
随着网络用户的日益增长,互联网记录着大量的用户个人信息和由智能终端产生的图片和信息,这些信息爆炸性的增长,并不断涌入网络海洋,产生海量的数据信息。在电子商务环境中大数据处理将会发展出更多强大和多元的功能。本文以淘宝网为例,分析研究如何合理利用数据,为企业的经营模式做出相应调整,并且在变化中不断进行企业新技术、新方法和新思路的探索。同时指出数据泄露的隐患,并给出相应建议。 相似文献
160.
We develop a structural risk‐neutral model for energy market modifying along several directions the approach introduced in Aïd et al. In particular, a scarcity function is introduced to allow important deviations of the spot price from the marginal fuel price, producing price spikes. We focus on pricing and hedging electricity derivatives. The hedging instruments are forward contracts on fuels and electricity. The presence of production capacities and electricity demand makes such a market incomplete. We follow a local risk minimization approach to price and hedge energy derivatives. Despite the richness of information included in the spot model, we obtain closed‐form formulae for futures prices and semiexplicit formulae for spread options and European options on electricity forward contracts. An analysis of the electricity price risk premium is provided showing the contribution of demand and capacity to the futures prices. We show that when far from delivery, electricity futures behave like a basket of futures on fuels. 相似文献