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1.
专利作为技术和知识的重要载体,是研究技术演进和产业发展的重要信息源。目前缺乏针对专利集群网络中关键节点与关键路径中节点的比较分析和技术知识挖掘。构建基于关键节点和关键路径的专利集群网络演进模型,从两个层面综合分析技术演进特征。检索德温特数据库(Derwent Innovation Index)得到碳化硅肖特基势垒二极管(SiC-SBD)相关专利作为实证数据,时间跨度为1986-2017年。结果表明,SiC-SBD专利集群网络经历了萌芽期、成长期、成熟期和衰退期,其中,萌芽期专利主要涉及基础技术,成长期为器件结构,以完善器件结构、改进二极管性能为主要研究方向。近年来SiC-SBD专利年增长率下降,技术发展速度放缓,专利价值更多体现在其商业价值上。SiC-SBD专利集群网络关键节点与关键路径中节点重合度较高,核心专利识别可通过多视角分析得到。通过关键节点与关键路径分析专利集群网络演进过程,有助于更全面呈现技术演进过程,为决策者识别核心专利、预测技术发展提供参考。  相似文献   
2.
以我国各省知识产权保护制度为研究对象,创新性地将探索性空间数据分析方法与社会网络分析方法相结合,基于地理邻近视角,验证了区域知识产权保护的空间相关性、空间集聚特征和空间溢出效应。同时,突破地理近邻效应的局限,解析区域知识产权保护的空间关联特征。结果表明:我国各省知识产权保护具有全局自相关性,相似地区间存在空间集聚效应,不同发展程度地区的空间关联性质不同;网络化后的区域知识产权保护各节点间联系紧密、网络结构稳定,并且可以确定核心行动者和边缘行动者角色;长三角、珠三角、环渤海等较发达地区与其它地区之间存在较多溢出关系。  相似文献   
3.
国家高新区是培育经济增长新动能,实现区域经济高质量发展的重要政策载体,文章利用2001-2014年我国261个城市面板数据,通过渐进双重差分法研究国家高新区设立对城市全要素生产率的影响。研究发现:研究期内国家高新区的设立对城市全要素生产率造成显著的负面影响;从TFP的分解项来看,高新区设立促进了所在城市规模效率提高,却抑制了技术进步和技术效率提高;异质性分析结果表明上述作用具有显著城市等级异质性,在高行政等级城市设立高新区对城市全要素生产率具有促进作用。进一步运用工业企业数据库、微观土地转让数据、城市专利数据等进行机制分析发现,企业间资源错配和土地价格扭曲降低了技术效率,而技术创新下降和产业升级钝化是抑制技术进步的主要机制。  相似文献   
4.
The travel, tourism and hospitality industries have been the worst affected of the world's major economic sectors during the COVID19 pandemic, which has had a devastating effect on both destinations and organisations. Drawing from a sample (N = 385) of adult permanent residents of Athens, Greece, the study examines the impact of COVID19 upon holiday intention. The chaordic systems are evaluated through the use of fuzzy-set Qualitative Comparative Analysis, whilst the study also used Necessary Condition Analysis for the calculation of the size effects of the examined conditions. The findings reveal two sufficient complex configurations leading to holiday intention: (i) holiday risks, and (ii) impact of COVID19. Based on the results, the article also offers a set of managerial implications. The contribution of the study is to both theoretical and methodological tourism domains.  相似文献   
5.
New product activity is critical for sustained success of consumer packaged goods (CPG) brands. However, the impact of new SKUs on the perceived quality, quality uncertainty and subsequent choice of the brand as a whole is, as of yet, not well understood. The authors study how new additions to the brand line shape consumers’ quality perceptions, and how this – next to the mere line length effect – influences their choice of brands over time. They do so in the setting of an emerging market (China), where new product activity is particularly pervasive. Using a unique scanner panel dataset of Chinese households over the period 2011–2014, they estimate a Bayesian learning model that accommodates varying quality, on two CPG categories, and for two types of new-product additions (new sensory SKUs vs. new non-sensory SKUs). They show that while adding new SKUs may lift the brand’s perceived quality level, it also makes consumers more uncertain about the quality of the brand – dampening their brand choice. This holds especially for light customers – an important part of the brand clientele. Managerial implications are discussed.  相似文献   
6.
The “industry nurturing agriculture” reforms and World Trade Organization accession led to dramatic growth in public expenditure and international trade in China’s agricultural sector. This article aims to estimate the effects of public expenditure and trade on agricultural productivity in China for 2004–2015. A semi-parametric production function with shape constraints is introduced to derive more accurate productivity before the productivity determinants are analyzed with an emphasis on public expenditure and trade. The empirical result shows that public expenditure and exports can effectively improve agricultural productivity, while imports have no significant effects. Policy implications are discussed in the context of supply-side reforms.  相似文献   
7.
Islamic equity portfolios work with a smaller investment universe given the filtering of non-Shari’ah compliant stocks. It has been theoretically argued that this culminates in suboptimal portfolio diversification, which in turn adversely affects risk-adjusted returns. We offer empirical evidence that such a conceived portfolio diversification “penalty” is far from a foregone conclusion, at least empirically. Our results tend to indicate that Islamic portfolios are not invariably handicapped in terms of portfolio diversification. We also explored dimensions that may account for differences in the relative investment performance between Islamic and conventional portfolios, such as portfolio constraints, short selling and market conditions. We believe this paper is among the first to apply substantial empirical analysis specifically with respect to the portfolio diversification perspective on Islamic equity investments.  相似文献   
8.
This paper proposes a new framework for the estimation of product-level global and interregional feedback and spillover (FS) factor multipliers. The framework is directly based on interregional supply and use tables (SUTs) that could be rectangular and gives a possibility of taking account of the inherent input–output data uncertainty problems. A Bayesian econometric approach is applied to the framework using the first version of international SUTs in the World Input–Output Database. The obtained estimates of the global and intercountry FS output effects are discussed and presented at the world, country and product levels for the period of 1995–2009.  相似文献   
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10.
Abstract

This research investigates the persistence of price–cost margin (PCM) and technical efficiency (TE) of firms and the relation between these two factors in 44 subsectors of the Indonesian food and beverage industry in the period 1980–2014. Data envelopment analysis with a bootstrapping approach is applied to estimate TE. An autoregressive model, accounting for endogeneity, is applied to estimate the persistence coefficients of PCM and TE. A cross-sectional regression model is also applied to estimate the relation between the persistence of the PCM and the persistence of TE. The results show that for these food and beverage firms, high PCM and low TE persist. Furthermore, the persistence of PCM negatively affects the persistence of TE in the industry.  相似文献   
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