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41.
基于颠覆性创新、创新扩散、创新模糊前端等相关理论,从全流程角度创新性地构建了颠覆性创新四阶段扩散过程模型,包括颠覆性创意产生、颠覆性创新产品开发、侵蚀非主流市场、占据主流市场4个阶段,各阶段之间相互关联、循环往复,并受到技术、市场、政策、竞争等外部环境因素影响。选取液晶电视机和山寨手机作为高端和低端两个颠覆性创新典型案例,通过对其进行验证性分析,构建具体的高端与低端颠覆性创新四阶段扩散过程模型。  相似文献   
42.
This article studies poverty persistence and the role of social security programmes on poverty among elderly in the US. We use a Latent Markov model to disentangle unobserved heterogeneity and state dependence. Because of its dynamic nature, unobserved heterogeneity is modelled to vary over time. This allows to capture different latent states of poverty that change over time. Result indicates the existence of three unobserved types evolving over time according to their propensity to be poor. Moreover, a strong persistence in poverty especially for women, individuals living alone and ethnic minorities is found. Finally, the estimates indicate that giving social assistance tends to reduce poverty.  相似文献   
43.
When employees are empowered to continuously record their employment-related frustrations—doing so on accessible, visually prominent media—process improvement becomes upgraded to operate in a truly continuous mode. Frustrations are a superior target of process improvement in that they get at deep-seated concerns of people who have first-order process awareness and are most directly impacted by process failings. Recording frustrations not only provides a sound basis for pressing on to solutions, but it is also cathartic. The act of recording frustrations prominently on company-sanctioned media provides a positive outlet for the frustrations themselves.  相似文献   
44.
ABSTRACT

This study discusses how to apply counseling-learning (CL) principles to a particular e-learning solution for teaching a tourism-related subject via a massive open online course (MOOC). Several effective caring patterns in achieving learning-related goals and being part of a community according to the CL principles are presented and discussed using the MOOC “eTourism: Communication Perspectives” as a case study. The study underlines how the MOOC platform can act as a place for contents enjoinment and active learning. Moreover, the active role of social media for increasing the engagement of learners in the proposed activities and for developing a sense of the community is identified. In particular, Facebook and Twitter can act as places for community building and informal social interactions among learners that last beyond the completion of the course, which in turn can be a valid aid for continuing the relationships among instructors/learners and learners/learners, and for reaching new ones.  相似文献   
45.
Academic research suggests a number of technology evaluation models. To ensure effective use, models need to be improved in accordance with changing internal and external environments. However, a majority of previous studies focus on model development, while a few emphasize their implementation or improvement. To fill this research gap, this study suggests a systematic approach to examining the validity of technology evaluation models and improving them. We consider three propositions as criteria for improvement: 1) the coherence of the evaluation results with the evaluation purpose, 2) the appropriateness of the evaluation methods, and 3) the concreteness of the evaluation model. Rather than using expert opinions, this study takes a data-driven approach, wherein we analyze actual evaluation results and determine whether the model produces the intended results. A case study of 291 technology evaluation results, all made by the South Korean government in support of technology-based small and medium-sized enterprises, is conducted to verify the suggested approach's applicability. This is one of the few studies to address issues regarding improvements to a technology evaluation model. Its approach can help to develop and continuously improve a valid technology evaluation model, thus leading to more effective practice.  相似文献   
46.
We propose a novel class of convex risk measures, based on the concept of the Fréchet mean, designed in order to handle uncertainty which arises from multiple information sources regarding the risk factors of interest. The proposed risk measures robustly characterize the exposure of the firm, by filtering out appropriately the partial information available in individual sources into an aggregate model for the risk factors of interest. Importantly, the proposed risks can be expressed in closed analytic forms allowing for interesting qualitative interpretations as well as comparative statics and thus facilitate their use in the everyday risk management process of the insurance firms. The potential use of the proposed risk measures in insurance is illustrated by two concrete applications, capital risk allocation and premia calculation under uncertainty.  相似文献   
47.
何慧爽 《水利经济》2018,36(2):62-67
为准确描述我国公民水素养水平,有针对性地加强水资源宣传教育,提高公民水素养,在科学素养、环境素养的研究基础上,设计包含有水知识、水态度、水行为3个一级指标、10个二级指标、29个三级指标的公民水素养多层级评价指标体系,运用层次分析法和李克特量表分别确立各级指标权重和设计调查问卷,并以北京市为例对公民水素养评价指标体系进行通用性分析。结果表明,水知识、水态度、水行为在水素养评价中各自的权重为9.14%、21.76%和69.10%;水知识、水态度得分相对较高,而水行为得分则相对较低,表明以水行为核心的水素养提升任务任重而道远。  相似文献   
48.
Trade openness is an important determinant of the inflation process. The effect of trade openness on inflation, however, is still an issue of debate at both theoretical and empirical levels. This study tried to provide a contribution to the literature by examining the relationship between inflation and trade openness in Tunisia over the period 1975Q1-2015Q4 using a nonlinear model. The originality of this study stems from the fact that it is the first investigation considering both the Residual-Based Tests for Cointegration in Models with the Regime Shifts and Threshold Regression model. The linear model confirms the existence of a positive relationship between inflation and trade in Tunisia. Yet, considering the nonlinear model, trade openness growth and Consumer Price Index (CPI) inflation growth show a statistically significant negative link as long as the trade openness evolution does not exceed the threshold. Nevertheless, if the trade openness growth is higher than the threshold, integrating the trade positively affects CPI inflation. Furthermore, a positive influence of Money supply growth on this type of inflation was noticed in Tunisia in all the considered regimes proving the effect of monetary factors on inflation level. Consequently, trade openness could be used to control inflation in Tunisia.  相似文献   
49.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
50.
Many experts agree that more agricultural investment is needed in the global South to improve local food security and reduce poverty. However, there is a lack of consensus about the types of investment needed to achieve these goals. This paper contributes to the literature on large agricultural investments and corresponding business models by inventorying and analysing such investments in Kenya’s Nanyuki area. We identify four clusters of business models that differ primarily by type of production and other distinct determinants, namely: demand from markets; access to land; land tenure regime and colonial history; actors involved; biophysical context; labour availability; and governance of the value chain via private standards. The study results shed light on the factors that help or hinder implementation of large agricultural investments and shape their impacts in the context of African land use systems. The way land is accessed represents one of the most-decisive factors determining the risks and opportunities associated with such projects. We find that most investments in the Nanyuki area occur on land bought or leased from private owners.  相似文献   
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