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1.
技术要素转移与交易对技术中介有较强的依赖性,而技术中介的存在能够有效降低交易过程中的信息失衡,为买方交易提供必要支持,技术中介服务直接影响技术交易效率。当代技术中介服务已经形成较大规模,提供服务的种类也较为全面,整体上适应了技术市场发展需要。但是,由技术中介参与的大量交易都存在低端化倾向,据此提出中介服务下沉化假设,并构建选择影响因素模型。通过对买方企业数据的采集与回归,发现无论是全样本还是分类样本均有效验证了主要假设变量。因此,为保障技术中介合理发展,从政策层面应重点关注如何提升服务质量,使其服务于中高端技术交易需求。  相似文献   
2.
基于2005—2018年中国内地285个地级市数据,对城市科技人才集聚与全要素生产率(简称“TFP”)进行测度分析,实证考察科技人才集聚对TFP的影响。结果表明:①城市科技人才集聚与TFP空间分异特征显著,但二者具有较强的时空一致性,即科技人才集聚特征显著的城市,其TFP也相对稳定;②城市科技人才集聚对TFP的影响呈倒U型,但研究期内大多数城市仍处于集聚效应占主导阶段,科技人才集聚通过提升城市技术进步水平促进TFP增长,而科技人才集聚对技术效率的影响呈倒U型;③不同类型城市科技人才集聚对其TFP影响的异质性显著,且适宜集聚区间也存在差异。省会城市及一、二线城市等优势特征显著的城市所能承受的科技人才集聚规模上限更高,有利于通过释放集聚红利促进TFP增长,而非省会城市、三线及以下城市等则拐点值较低。  相似文献   
3.
Programs to improve water quality do not improve all water bodies equally. Evaluation of the benefits of such programs must account for where improvements occur and the relative magnitude of improvements that occur in different places. This study uses a choice experiment survey to explore how the value to a household of a surface water quality improvement varies as a function of (i) the distance between the household and the affected streams and rivers, (ii) the degree to which the quality of the water has been improved, (iii) how many stream and river miles have been improved, and (iv) the sizes of the affected streams and rivers. Results show evidence that value declines with distance in an approximately linear way, weak evidence that large rivers are worth more than small rivers, and no evidence that willingness-to-pay is nonlinear in either the degree of water quality improvement or the number of stream miles improved. These results indicate that it may be defensible in applied work to value small, spatially-explicit water quality improvement projects independently and then sum over projects.  相似文献   
4.
陈媛  王伟华  王福颖 《科技和产业》2023,23(16):154-159
选取2021年度数据,采用数据包络分析(DEA)方法对中国东部地区10个省份规模以上工业企业的研发投入绩效进行评价,并采用灰关联分析方法分析确定各项研发投入产出指标相对于DEA效率的灰色关联度。研究结果表明,80%的省份规上工业企业研发投入产出处于非DEA有效状态,存在不同程度的投入冗余或产出不足;规上工业企业发明专利申请数与研发投入产出效率的关联度最高,其次是新产品销售收入和R&D经费内部支出。  相似文献   
5.
传统方法在建筑材料供应链质量数据安全共享中应用效果不佳,不仅数据误码率比较高,而且数据共享时延比较长,无法达到预期的数据安全共享效果。为此提出基于区块链技术的建筑材料供应链质量数据安全共享方法。利用区块链技术对建筑材料供应链质量数据属性加密,建立建筑材料供应链质量数据安全共享链,整合建筑材料供应链质量数据加密、解密程序,通过对用户身份验证实现对质量数据安全共享,以此完成基于区块链技术的建筑材料供应链质量数据安全共享。实验证明,设计方法的数据误码率在1%以内,数据共享时延在1s以内,具有良好的数据安全共享效果。  相似文献   
6.
The panic buying behavior under public health emergencies will lead to many adverse consequences, such as material waste, price fluctuation and uneven distribution of epidemic prevention materials, which will pose a threat to the social stability and economic development. In this paper, we construct a tripartite game model to explore the strategic choices of the public, merchants and the government in order to effectively respond to the panic buying behavior in the epidemic. The results demonstrate that: (1) Eight evolutionary stable strategies emerge in the panic buying events. The worst scenario can be improved by adjusting some relevant parameters. (2) The probability of the public choosing the strategy of “not involving in panic buying” depends on the potential benefits and losses of snapping up, rather than the extent of price rising. (3) The probability of merchants choosing the strategy of “not bid up price” depends on the intangible benefits. (4) The probability of the government choosing the strategy of “active supervision” depends on the supervision costs and government credibility, rather than the amount of fines. In addition, strategic suggestions to mitigate panic buying behavior are put forward from the perspective of each stakeholder.  相似文献   
7.
This study aims to establish various market segments based on consumers' attitudinal elements influencing the adoption of mobile payments (m-payments). It also examines the best discriminators between identified clusters of m-payment users. Three hundred and sixty m-payment users participated in the study. Cluster and discriminant analyses were employed for the analysis. The findings suggest that two segments are established, and strategies can be developed accordingly. The study provides marketers with numerous touchpoints to propagate the adoption of m-payment apps. It also comprehensively explains m-payment users in developing economies by superimposing the cohorts to Roger's diffusion of innovation model.  相似文献   
8.
为探究生产安全事故的演化规律,基于长沙市2019—2020年生产安全事故的数据,从事故发生时间、发生区域、行业和领域分布、事故等级等方面进行分析。研究表明:2019—2020年事故数量和死亡人数呈下降趋势,1月、8月、10月事故数量和死亡人数较多,2月事故数量和死亡人数少;非主城区的事故数量和死亡人数高于主城区,事故数量和死亡人数在空间上的分布比较均衡;道路运输和工矿商贸行业在全市生产安全事故中占绝大多数;工矿商贸行业中,建筑施工行业的事故数量和死亡人数最多;一般事故所产生的事故数量和死亡人数最多,重大事故的事故死亡率最高。  相似文献   
9.
Customer satisfaction is the main pillar for convenient and profitable retailing. The retail sector continuously tried to develop new strategies to improve consumer satisfaction. It is impossible to provide each service directly to the consumer by the retailer. In this direction, the retailer establishes customer care to provide the best service to consumers. Consumer care can provide promotional or prevention services, increasing the consumer's satisfaction level. This study is developed to show the impact of retailers' customer care service for an offline-to-online retailing strategy. The demand is consumer support, advertisement, and selling price dependent. For maintaining consumer service, some free home delivery policies are offered, when consumers ordered more than a certain percentage of the amount. Finally, the total profit of this O2O retailing system is calculated by the classical optimization technique. Some special cases are discussed in the numerical section to prove the impact of customer care services. Numerical results prove that customer care support enhances the profit by 48.20%, whereas investment in the advertisement and home delivery strategy helps the retail industry to earn 44.80% and 16.74% more profit, respectively. Finally, from this study, it is clear that customer care activities are essential to increase the profit of the retailing sector.  相似文献   
10.
We collected 469 frontal face images of Ukrainian cabinet ministers who were in office in 2000–2020. For each image, the minister's body mass index was estimated using a computer vision algorithm. The time series of median estimated body mass index of cabinet ministers co-moves over time with two existing measures of corruption – World Bank worldwide governance indicator Control of Corruption, and the discrepancy between the quantity of luxury wristwatches exported from Switzerland to Ukraine (reported by Swiss statistics) and the corresponding quantity imported by Ukraine from Switzerland (reported by Ukrainian statistics).  相似文献   
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