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21.
A duopoly model is developed in which firms' strategic variables include brand quality, the number of distinct market segments to enter and price. Informative advertising is used to overcome consumer ignorance about brands. In contrast to many existing models in which firms engage in price competition, the subgame perfect equilibria of the game are not characterised by the production of vertically differentiated products. Further, whilst the firms typically produce identical high quality products, in some circumstances the production of homogeneous low quality brands can be an equilibrium strategy.  相似文献   
22.
在理解农民合作的内在机理中,政府的角色是不可或缺的,但政府的介入往往形成一个"悖论"。通过分析新中国成立以来农民的合作历史,展示了政府进退对农民合作的影响。结合目前农民合作的现状,分析由于政府缺位,制度资源供给不足,农民合作陷入困境。因此,由于农民自组织资源的局限性,政府介入农民合作是必要的,但要注意介入的尺度,要在公共决策与私人决策之间保持平衡。  相似文献   
23.
采用Czochralski法生长出一系列不同Ho3+(0.1,0.3,0.5 mol%)摩尔掺杂浓度的Ho:LiNbO3单晶。X射线衍射结果显示了Ho:LiNbO3晶体的结构特性。在550nm光源的激发下,在样品中检测到了由于3D3→5IJ(J=6和8)和5Gk→5I8(k=3,4,5和6)能级跃迁引起的紫外至紫光区域的上转换发光。交叉弛豫5G4+5I8→5F4/5S2+5I6导致了发光强度随着Ho3+掺杂浓度增加而减弱。晶体的紫外-可见光-进红外吸收光谱表明在Ho3+掺杂浓度为0.3mol%和0.5mol%时,Ho3+占据了LiNbO3晶体的Nb位。  相似文献   
24.
25.
再论我国蔬菜出口现状及策略   总被引:5,自引:0,他引:5  
加入WTO后,当我们的出口产品在比较顺利地通过关税壁垒时,进口国为保护本国市场,将以技术壁垒阻弱势企业的加入。而与国际标准相比,我国蔬菜质量标准普遍偏低,向质量要效益是蔬菜行业的当务之急。  相似文献   
26.
This article studies the impact of health insurance on individual out‐of‐pocket health expenditures in China. Using China Health and Nutrition Survey data between 1991 and 2006, we apply two‐part and sample selection models to address issues caused by censored data and selection on unobservables. We find that, although the probability of accessing health care increases with the availability of health insurance, the level of out‐of‐pocket health expenditure decreases. Our results from a selection model with instrumental variables suggest that having health insurance reduces the expected out‐of‐pocket health expenditure of an individual by 29.42% unconditionally. Meanwhile, conditional on being subjected to positive health expenditure, health insurance helps reduce out‐of‐pocket spending by 44.38%. This beneficial effect of health insurance weakens over time, which may be attributable to increases in the coinsurance rates of health insurances in China.  相似文献   
27.
The widespread use of barcodes has significantly contributed to accurate, efficient and economic inventory management in warehouses and distribution centres. However, its efficiency has always been limited by the primary method of reading barcodes with a handheld laser scanner. Compared with this reading by line-of-sight at close proximity, vision-based barcode reading algorithms can further improve efficiency, particularly if accompanied by automated data collection platforms such as drones. This paper introduces algorithms that are able to automatically extract barcodes from video data, and verifies their feasibility and promise for inventory management in warehousing applications. Three key techniques corresponding to different recognition levels are proposed: For a known barcode region, a Harris corner detector and Hough transform-based algorithm is applied to quickly estimate the angle by which the frame area needs to rotate to orient the bars vertically for information extraction. Then, the idea of exploiting connectivity and geometry property of barcode areas is proposed to directly recognise multiple barcode regions in a single video frame to eliminate reading difficulties resulting from interactive influence of multiple juxtaposed barcodes, and to save computation time by only processing frame areas of interest for valid barcodes. In addition, a histogram difference-based fast extraction strategy is designed to further improve efficiency by reducing duplicate information processing. Finally, the performance of each technique is evaluated by analysing video data from a large logistics warehouse, demonstrating satisfactory performance in inventory management applications.  相似文献   
28.
Our paper presents an empirical analysis of entrepreneurial well-being using a large-scale longitudinal household survey from the UK that tracks almost 50,000 individuals across seven waves over the period 2009–2017, as well as a number of exploratory case studies. We contribute to the existing literature by investigating how entrepreneurial well-being varies across locations along the urban-rural continuum, and across wealthy-deprived neighbourhoods. We use a Coarsened Exact Matching (CEM) approach to compare the well-being outcomes of individuals who switch into self-employment from waged employment, and show that entrepreneurial well-being, in the form of job satisfaction, is significantly higher for those living in semi-urban locations, relative to those living in urban and rural locations. We argue that semi-urban locations provide an optimal combination of ease of doing business and quality of life. Our results also show that individuals in wealthy neighbourhoods who switch into self-employment experience higher job satisfaction than otherwise comparable individuals living in materially deprived neighbourhoods, although the latter experience greater levels of life satisfaction following the switch.  相似文献   
29.
During the last few years there has been an increasing trend for companies to market their products or services as green or environmentally friendly as part of their corporate social responsibility. Few studies have analyzed the effects of this recent focus on the environment and its impact on airline passengers. Therefore, we examine passengers' general attitudes towards the green image of different airlines, perceived differences in eco-friendliness among these airlines, and effects on airline choice during booking. We also investigate how passengers' recent experiences with an airline affect perceived eco-friendliness of that airline. In addition we compare passenger ratings of airline eco-friendliness to those published by independent 3rd parties. Our findings show that the green image of airlines does influence airline choice during booking. We observed a passenger willingness to pay extra for a green image, however, not as much as their willingness to pay extra for amenities, such as additional legroom.  相似文献   
30.
It is estimated that world military spending in 2011 amounted to over 2.5% of the world's Gross Domestic Product (GDP). This corresponds to a spending of $233 per person in the world at 2010 constant prices, an amount close to the GDP per capita of the poorest country in the world. Therefore, it is important for economists to understand the allocation of resources to this sector of the economy. I present a model that explores the determinants of a country's level of military spending. I show how greater gains from trade can lead to greater military expenditures to protect them. It is also found that expansion in the demand for a country's tradable commodities, that is, an improvement in that country's terms of trade, will impact defense spending. Several other propositions emerge from the model which are then empirically tested using both pooled and time series data. The statistical results support the model's propositions.  相似文献   
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