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101.
Abstract. In this paper we analyse productivity spillovers from foreign direct investment using firm-level panel data for U.K. manufacturing industries from 1992 to 1999. We investigate spillovers through horizontal, backward, and forward linkages; distinguish spillovers from export-oriented vs domestic-market-oriented FDI; and allow for differing effects, depending on domestic firms' export activities. The results suggest that the mechanisms through which spillovers affect domestic firms are very complex and that there are substantial differences in spillover benefits for domestic exporters and non-exporters, and from different types of inward investment. 相似文献
102.
Lichao Xu Vineet R. Kamat Carol C. Menassa 《International Journal of Logistics Research and Applications》2018,21(3):243-258
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
103.
以氰乙酸乙酯、2-萘酚和对氯苯甲醛为反应原料,得到了3-氨基-1-(4-氯苯基)-1氢-苯并[f]色烯-2-碳酸乙酯,通过X-射线单晶衍射对其结构进行表征。结果表明:晶体属于三斜晶体,空间群为P-1。晶胞参数为:Z=2,a=9.2916(7)A°,b=9.4505(8)A°,c=10.9761(7)A°;α=95.077(2)°,β=98.200(2)°,γ=102.892(2)°,V=922.65(12)A°3;R1=0.0466,wR2=0.1326。 相似文献
104.
黄世贤 《江西财经大学学报》2009,(2):47-53
我国现有农村公共服务政策是在特定的经济、政治、文化和国际环境背景下形成的.新世纪以来出台的一号文件及涉农决定凸显了政府提供农村公共服务的内涵,标志着全新的执政理念和政府职责的确立,其政策效果已经和正在发生巨大作用.但要构建一个适应社会主义市场经济体制要求的农村公共服务体系还有很长一段路要走. 相似文献
105.
The objective of this study is to investigate unpacked and packed fluid milk consumption patterns and preferences among Turkish households by using cross‐sectional survey data from 18,278 households. Based on the data, 47.8% of the households consume unpacked milk, 29.3% consume sterilized milk, and 7.9% consume pasteurized fluid milk at least once a month. Results of the multinomial logit model for fluid milk consumption behavior suggest that unpacked fluid milk preference is related positively to household size, income and age of the household head, and negatively to education level of the household head and status of the household wife. Similarly, pasteurized and sterilized fluid milk preferences are related positively to income and the education level of the household head, and negatively to household size and age of the household head. Results from these analyses are used to suggest techniques for marketing fluid milk products to specific segments of the consumer population. 相似文献
106.
Evidence has shown that parental smoking can cause health problems for children. It might be expected that parents who are aware of the harmful effects of second-hand smoke will reduce their smoking, especially as they have more children. However, based on instrumental variable regressions using data from the 2006 and 2008 Vietnam Household Living Standard Surveys, we find a strongly positive and significant effect of the number of children on the probability of tobacco smoking in households in Vietnam. An additional child increases the probability of tobacco consumption in the household by approximately 15%. These findings imply low levels of awareness of the harmful effects of second-hand smoke on children’s health in Vietnam, and indicate the need for policy action to disseminate knowledge on the harmful effects of smoking. 相似文献
107.
Designing and evaluating sustainable development pathways for semi‐subsistence crop–livestock systems: lessons from Kenya
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Achieving the Sustainable Development Goals (SDGs) in African agriculture requires a better understanding why high levels of poverty and resource degradation persist in African agriculture despite decades of policy interventions and development projects. In this article, we hypothesize that policies need to account for the key features of the semi‐subsistence crop–livestock systems (CLS) in the region to become effective. The semi‐subsistence CLS are characterized by a high degree of biophysical and economic heterogeneity and a complex, diversified production system involving a combination of subsistence and cash crops with livestock. We investigated the potential for interventions proposed by the Government of Kenya to meet the SDGs by 2030. The analysis uses an integrated modeling approach designed to deal with the key features of these systems. A strategy that stimulates rural development, increases farm size to a sustainable level, and reduces distortions and inefficiencies in input and output markets could lead to a sustainable development pathway and achieve the SDGs for rural households dependent on CLS. 相似文献
108.
Pseudo panel data estimation technique and rational addiction model: an analysis of cigarette,alcohol and coffee demands
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We use a pseudo‐panel data approach to analyze the relationship between the consumptions of cigarettes, alcohol, and coffee in a rational addiction framework. We find that while cigarette and coffee demands fit well with the rational addiction model, alcohol demand conforms to a model with inventory effects. The results suggest that alcohol consumption increases the marginal utility derived from consumption of cigarettes. Increasing alcohol prices would decrease not only the consumption of alcohol, but also the consumption of cigarettes. On the other hand, increasing cigarette prices do not have the same effect on consumption of alcohol. The cross‐price elasticity of coffee with respect to cigarette price is positive and significant which suggests that coffee substitutes for cigarettes when cigarette prices increase. The cross‐price elasticity of alcohol with respect to coffee price is found to be negative and significant. On the other hand, Morishima elasticities of substitution indicate that cigarette, alcohol and coffee substitute each other along the indifference curve when relative prices change. 相似文献
109.
随着航空飞行器种类和数量的激增以及第五代(5G)移动通信系统和物联网(IoT)时代的到来,下一代航空无线通信系统面临着高安全性、大传输容量、低延时、强鲁棒性、高灵活性和综合业务提供等新的挑战。为此,提出了一种基于L频段数字航空通信系统1(L-DACS1)的滤波正交频分复用(F-OFDM)波形设计方法并探讨了可能的技术演进路径。首先引入了认知无线电、非连续载波干涉码OFDM和滤波器的思想,然后针对不同航空飞行器用户动态自适应配置波形参数。仿真结果表明,该方法得到的系统波形具有较低的带外辐射功率、优良的块误码率性能和较高的吞吐量增益。 相似文献
110.
Nico L. van der Sar 《De Economist》2003,151(3):271-292
For daily data on a value-weighted index of all shares in the Netherlands (1981-1998), we find abnormally high returns in the pre-Christmas period of the second half of December and around the turn of the month, whereas returns are negative and volatility is relatively high on the Mondays where the previous week's return is below zero. Furthermore, our evidence indicates the presence of an ARCH(1) effect. Our intraday results based on an equal-weighted index of the leading shares in the Netherlands (1986-1993) reveal a U-shaped return pattern over each trading day, Monday morning excluded. Moreover, our tests reveal repeated price adjustments mostly in the same direction around and over non-trading periods. We argue that the arrival of private information is affected by strategic and behavioral factors incompatible with the risk-return paradigm. 相似文献