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排序方式: 共有7710条查询结果,搜索用时 15 毫秒
101.
通过分析授权发明专利的发明人相关数据来发现研发人才分布特征是一种新探索,解决了战略性新兴产业分类、专利IPC分类和研发人才领域分类对应关系复杂的问题,完成了对15个副省级城市专利发明人分领域相关数据的提取建库和一个样本城市细分领域研发人才的数据建库,进而比较分析研发人才分布特征,并耦合分析相关新兴产业发展态势。  相似文献   
102.
We examine policy‐related economic uncertainty effects on the availability of credit, non‐performing loans and loan loss provisions using a panel of 18 countries. We provide significant evidence that uncertainty reduces the availability of credit while leading to increases in banks' non‐performing loans and loan loss provisions, distorting sectoral stability. Our findings are economically meaningful.  相似文献   
103.
This paper studies entry decisions in contests with private values. Potential contestants observe their value and the common opportunity cost of entry, and make entry decisions simultaneously. Theory predicts that whether or not contestants are informed of the number of entrants prior to choosing their expenditures has no effect on entry or aggregate expenditures. We test these assertions in our experiments. We find substantial over-entry in both information structures. However, entry is higher when contestants are informed. Since expenditures do not, on average, differ across information structures, aggregate expenditure is also higher when contestants are informed. Contestants earn on average less than the opportunity cost of entry.  相似文献   
104.
While most major reforms of health systems fail, those that succeed are motivated by politicians' quest for reducing the health burden on their budget in response to a shift in voters' preferences away from public health. An Edgeworth box is used to depict their preferences, in addition to those of (potential) patients and health‐care providers. Politicians are found to severely constrain the area of mutual advantage, suggesting that only minor reforms are possible unless they promise to lower health‐care expenditure. An efficiency‐enhancing change that would enlarge the box and hence the area of mutual advantage would be to suppress the requirement imposed on health insurers to purchase domestically, rather than being free to directly import health‐care services and drugs.  相似文献   
105.
This study analyses the effect of the spatial factor, location, and interaction effects among peer companies, on the productivity growth of agri‐food companies in Spain. With this aim, we build a productivity growth index and apply a multiequational Seemingly Unrelated Regression on a sample of 344 Spanish cooperatives and investor‐owned firms for the period 2010–2012. Our findings show that agri‐food firms are influenced by spatial factors finding interesting differences between cooperatives and investor‐owned firms. With regard to the geographical location, cooperatives in the western of Spain show higher productivity growth rates, whereas investor‐owned firms in the northeast of Spain present better results. The interaction effect among closer peer companies is also a relevant factor to determine the productivity growth in agri‐food companies. This factor is more relevant for cooperatives than for investor‐owned firms.  相似文献   
106.
This article estimates the pass‐through rates between diesel fuel and retail milk prices at the product brand level. Using a random coefficient logit demand model and taking the direct and indirect impacts of energy prices, this research identifies changes in pass‐through rates before and after the great recession in 2008. Empirical results show that diesel prices significantly impacted the retail prices of milk products and are an important determinant of food price inflation. Pass‐through rates are estimated to range from 0.16 to approximately 0.60 through 2008 with an average of 0.22 for the whole period. Statistical tests indicate that pass‐through rates before June 2008 were significantly higher than after June 2008 when they dropped significantly to 0.04 to 0.17. Interestingly, private label brands have the lowest pass‐through rates, implying that compared to manufacturer brands, private label prices are more insulated from diesel price shocks.  相似文献   
107.
We examine the effects of broadband speed on county unemployment rates in the U.S. state of Tennessee. We merge the older National Broadband Map dataset and the newer FCC dataset in lengthening our broadband access data over the period 2011–2015. Extending the dataset improves the precision of the estimates. Our panel regressions control for potential selection bias and reverse causality and show that broadband speed matters: unemployment rates are about 0.26 percentage points lower in counties with high speeds compared to counties with low speeds. Ultra-high speed broadband also appears to reduce unemployment rates; however, we are unable to distinguish between the effects of high and ultra-high speed broadband. We document beneficial effects of the early adoption of high speed broadband on unemployment rates. Better quality broadband appears to have a disproportionately greater effect in rural areas.  相似文献   
108.
刘艳 《科技和产业》2018,(11):49-52
Catapults(弹射中心)作为一种新型研发组织形式,在英国创新发展战略的实施中扮演着重要角色。精准的组织功能定位、高效的组织管理运作模式和紧密的网络化组织关系,是Catapults组织管理模式创新的重要三大重要内容。为我国新型研发机构的培育和发展提供了良好的参考样本。  相似文献   
109.
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   
110.
In December 2014, the U.S. and Mexico agreed to a suspension agreement that set a $22.25/cwt import price floor on U.S. sugar imports from Mexico. A partial equilibrium trade model was developed to estimate the economic impact the agreement would have had if it had been in effect from 2008 to 2014. In years when the price floor would have been binding, on average, U.S. producers would have gained $138 million and Mexican producers would have lost $218 million. However, total Mexican welfare would have actually increased by $11.5 million. Furthermore, the average price floor that would have maximized total Mexican welfare over that period is $22.76/cwt. Also, under certain supply and demand elasticity conditions, the average price floor that would have maximized joint U.S. and Mexican producer welfare over that period is $21.91/cwt. The latter two estimates are both close to the actual price floor agreed to in the 2014 Suspension Agreement.  相似文献   
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