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61.
Forward citations of patents have been used extensively to capture the impact of technological knowledge. However, our understanding of the factors shaping patent citation patterns remains limited. One of the main limitations is the lack of scholarly attention paid to the dynamic influences arising from the evolution of technology fields. From an evolutionary perspective, technological impact is not simply determined by the static attributes of a technology itself; it is also dynamically affected by changes in the external conditions. Drawing on this viewpoint, this study suggests a model for understanding patent citation patterns by reflecting the evolution of the technology fields to which each patent belongs. Four such factors are explored: technology cycle time, potential of technological convergence, popularity of the technology field, and technological novelty. Based on the proposed model, we show how expected citation patterns can change as a result of different scenarios for technology field evolution. We conduct a case study of patents in the information technology and healthcare industries to show citation patterns of patents across heterogeneous industries as well as those within an industry. Contributions to the innovation literature and research investment decisions are discussed. 相似文献
62.
Yanfang Wu 《Journalism Practice》2019,13(5):537-557
American newsrooms are adopting social media as an innovation for greater engagement. However, several organizational and individual factors may affect the extent to which news outlets adopt social media innovations. In particular, there is assumed to be a divide among different age groups of journalists in embracing social media. Utilizing a structural equation modeling (SEM) analysis, the study seeks to understand how social media culture in newsrooms affects journalists’ strategies of taking social media as an innovation, and how journalists of different age groups differ in the SEM model fit. The analyses indicated Twitter engagement mediates social media culture and journalists’ attitude toward social media. However, that was not the case with Facebook. Additionally, while younger journalists favored Twitter, older journalists embraced Facebook and middle-aged journalists adopted both Facebook and Twitter. The analyses showed the more that middle-aged journalists interacted on Twitter, the more they tended to have a positive attitude toward social media. However, the more that younger and older journalists engaged on Twitter, the more they tended to have a negative attitude toward social media. Journalists from all three age groups tended to hold a negative attitude toward social media if they engaged more on Facebook. 相似文献
63.
美国非常重视公共部门信息的再利用。文章在对目前国内相关的研究文献进行综述的基础上,总结了美国推动公共部门信息再利用的主要经验,主要包括:制定严密的法律、实施开放的商业化运作、利用先进的信息技术以及大力倡导开放存取,以便推进公共部门信息再利用。文章以新公共管理为视角,揭示美国公共部门信息再利用对我国的有益启示。 相似文献
64.
65.
The extended unified theory of acceptance and use of technology (UTAUT2) is less than ten years old and has already garnered more than 6000 citations with extensive usage in information systems and beyond. This research employed cited reference search to systematically review studies that cited UTAUT2 originating article. Based on UTAUT2 usage, the downloaded articles were classified into four categories such as: 1) General citation, 2) UTAUT2 application, 3) UTAUT2 integration, and 4) UTAUT2 extensions. Weber's (2012) theory evaluation framework revealed UTAUT2 as a robust theory on most dimensions except for parsimony arising from the complex model. UTAUT2 extensions emerged as popular UTAUT2 utilization category as researchers extended the model with context specific variables. Finally, UTAUT2 extensions were mapped to Johns' (2006) context dimensions to identify various limitations of the existing technology adoption research and to provide multi-level framework for future researchers with libraries of context dimensions. 相似文献
66.
江俊勤 《广东教育学院学报》2014,(5):43-49
基于简并微扰论和Mathematica软件平台,发展了一种简单可靠、全自动的计算方法研究磁场中的原子能级结构.考虑自旋磁矩和感生磁矩,计算了处在较强磁场中氢原子n=2~7的能级和波函数.讨论了简并微扰论的适用条件和能级分裂,绘制了概率角分布图和电子云图.数值结果表明:对于较强磁场,本方法是可靠和快捷的;一般情况下,磁场对能级的一级修正可以使简并完全解除(n=2~7),但在一定条件下,会出现新的简并——偶然简并. 相似文献
67.
区域产业转移有利于转出地的产业结构升级,转入地经济的快速发展和产业结构调整。经过改革开放以来30多年的发展,苏浙沪地区出现大量产业对外转移现象,这对如安徽一样的中部地区是一个难得的发展机会。基于企业、产业、空间三个角度,根据苏浙沪和安徽经济发展现状和实际情况,对比分析了安徽在此次承接苏浙沪产业转移过程中所具有的拉力因素,阐明安徽将成为苏浙沪产业转移的首选地。 相似文献
68.
噪声是图像获取、传输和储存过程中不可避免的现象。去噪作为图像处理的首要步骤与基本问题是后续的高层次图像处理的基础。以加性高斯白噪声为例,综述了P-M扩散方程及TV模型的原理,并从视觉与定量指标两个方面比较了去噪效果。最后,在热扩散方程模型预处理条件下比较了两种模型的去噪效果。 相似文献
69.
以普通Al粉、LiAlH4和Li3AlH6作为Al源,分别与LiBH4进行球磨复合,通过对LiBH4/Al、LiBH4/LiAlH4和LiBH4/Li3AlH6复合物吸放氢过程的物相分析、放氢性能分析和吸氢性能分析,系统研究不同Al源对LiBH4储氢性能的影响,发现Li3AlH6分解提供的活性Al促进LiBH4放氢作用明显,并且其放氢产物的可逆吸氢动力学性能也最好。 相似文献
70.
根据YIN和WANG的方法,结合Fichera-Oleinik理论,研究奇异扩散方程:φ( u)/t =div(ραu p-2u),(x,t)∈QT =Ωx(0,T),其中Ω是RN 中的有界区域,边界Ω充分光滑,ρ(x)=dist(x,Ω), p 〉1,α〉0,φ满足:φ∈C2,且存在δ〉0使得φ′(s)〉δ〉0.证明了α≥p -1时,不需要任何边值条件,方程最多有一个满足初值条件的解;而0〈α〈 p -1时,方程存在唯一满足初边值条件弱解. 相似文献