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1.
科技金融是"第一生产力"与"第一助推力"的有机结合,承担着带动地区经济高质量发展的重要使命.基于当前我国科技金融结合不断推进的背景,文章以2007—2016年我国共285个地级市的面板数据为例,运用双重差分法(DID)对科技部、中国人民银行等五部门推行的科技金融结合试点政策对试点地区经济增长的带动效应及机制进行检验.结果表明:第一,科技金融结合试点政策能够有效带动试点地区经济增长,这一结论具有稳健性;第二,科技金融结合试点政策对试点地区经济增长的带动作用存在显著的地域性差异,东部最强、中部次之、西部最弱;第三,进一步的机制检验表明科技金融结合试点政策能够通过提升地区科技创新水平和推动产业结构合理化的双重路径带动地区经济增长.为了进一步推动科技与金融相结合,提升地区经济发展水平,各地政府应高度重视科技金融结合试点政策对地区经济发展的正外部性,积极申报试点城市建设.同时,应结合各地市情社情制定差异化试点政策,大力提升科技创新与产业结构合理化水平,充分发挥其对地区经济增长的中介作用.  相似文献   
2.
资本创造模型(CC模型)忽视了要素流动对产业空间分布的影响。而发展的新的资本创造模型则认为资本集聚的过程必然伴随着工业劳动力的流动过程。另外,是资本的实际收益而不是名义收益决定资本是否创造。研究结果表明,随着贸易自由度、工业品支出份额及资本贴现率的变大,替代弹性及资本折旧率的变小,将降低对称结构的稳定性,而提高中心-外围结构的稳定性;经济地理空间的产业均衡是集聚力和分散力相互作用的结果。当企业生产工业品的规模报酬递增程度足够显著,或者工业品支出份额很高时,市场拥挤效应将彻底消失,并转化成为促进产业集聚的动力;突破点与持续点的大小比较可以形成不同的关系,这意味着随着贸易自由度的变化,本文发展的资本创造模型可以体现出多样化的产业空间动态演化行为。  相似文献   
3.
BackgroundSupporting women to continue breastfeeding is a global challenge. The Milky Way Program is an effective face to face intervention to increase breastfeeding rates up to six months postpartum. The sustainability and access to the Milky Way Program could be enhanced by transforming it into a mobile application allowing women to access relevant information from their own place at a convenient time.AimTo explore the process of transforming the Milky Way Program into an acceptable and usable mobile health application.MethodStakeholders including multidisciplinary researchers and end-users designed the application based on the Milky Way Program by using Persuasive System Design principles. A mixed-method approach was used in the development and evaluation process. Seven women were recruited through convenience sampling to pilot test the application. The women’s feedback was collected through an online survey six weeks after birth and individual interviews at four months postpartum.FindingsWomen in the pilot study reported that the breastfeeding application was well designed, easy to use, interactive, reassuring and evidence-based with credible sources of information.ConclusionThe Persuasive System Design model combined with end-user engagement can feasibly inform the development of an acceptable and usable mobile health application for breastfeeding based on a proven clinical intervention. Further rigorous testing is required to evaluate the effectiveness of the application on breastfeeding initiation and duration.  相似文献   
4.
ABSTRACT

Correlated bilateral data arise from stratified studies involving paired body organs in a subject. When it is desirable to conduct inference on the scale of risk difference, one needs first to assess the assumption of homogeneity in risk differences across strata. For testing homogeneity of risk differences, we herein propose eight methods derived respectively from weighted-least-squares (WLS), the Mantel-Haenszel (MH) estimator, the WLS method in combination with inverse hyperbolic tangent transformation, and the test statistics based on their log-transformation, the modified Score test statistic and Likelihood ratio test statistic. Simulation results showed that four of the tests perform well in general, with the tests based on the WLS method and inverse hyperbolic tangent transformation always performing satisfactorily even under small sample size designs. The methods are illustrated with a dataset.  相似文献   
5.
Strong orthogonal arrays (SOAs) were recently introduced and studied as a class of space‐filling designs for computer experiments. An important problem that has not been addressed in the literature is that of design selection for such arrays. In this article, we conduct a systematic investigation into this problem, and we focus on the most useful SOA(n,m,4,2 + )s and SOA(n,m,4,2)s. This article first addresses the problem of design selection for SOAs of strength 2+ by examining their three‐dimensional projections. Both theoretical and computational results are presented. When SOAs of strength 2+ do not exist, we formulate a general framework for the selection of SOAs of strength 2 by looking at their two‐dimensional projections. The approach is fruitful, as it is applicable when SOAs of strength 2+ do not exist and it gives rise to them when they do. The Canadian Journal of Statistics 47: 302–314; 2019 © 2019 Statistical Society of Canada  相似文献   
6.
The case-cohort design is widely used as a means of reducing the cost in large cohort studies, especially when the disease rate is low and covariate measurements may be expensive, and has been discussed by many authors. In this paper, we discuss regression analysis of case-cohort studies that produce interval-censored failure time with dependent censoring, a situation for which there does not seem to exist an established approach. For inference, a sieve inverse probability weighting estimation procedure is developed with the use of Bernstein polynomials to approximate the unknown baseline cumulative hazard functions. The proposed estimators are shown to be consistent and the asymptotic normality of the resulting regression parameter estimators is established. A simulation study is conducted to assess the finite sample properties of the proposed approach and indicates that it works well in practical situations. The proposed method is applied to an HIV/AIDS case-cohort study that motivated this investigation.  相似文献   
7.
通过对抗性设计方法解决项目评审中的社会伦理问题,为专家、申请者、大众提供争论和表达异议的民主环境。项目自动评价平台完成民主环境的构建,呈现专家、申请者、平台的争胜性关系,揭示霸权,旨在重塑自由、平等、公平、正义、特权等的项目评审中的社会伦理。  相似文献   
8.
构建以国内大循环为主体、国内国际双循环相互促进的新发展格局,是对未来中国经济发展路径做出的重大战略部署,作为连接国内国际双循环的纽带,双向直接投资的发展战略和路径面临重塑和调整。研究认为,应当以推动新时代科技创新和产业升级为目标,提高双向直接投资的质量,畅通供应链和产业链; 以“一带一路”倡议为依托,通过更高水平的双向投资带动中国与沿线国家贸易水平的提高; 建设高水平自贸区和自贸港,提高对外开放标准,更高质量吸引外资,提升参与国际大循环的技术含量和自主性; 在畅通要素流动领域,建立更加完善的现代化物流体系,建设更高标准的要素流通市场体系,降低制度性交易费用,提高生产率和对高质量外资的吸引能力。  相似文献   
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10.
Business Modelling has evolved as a key activity to reflect new business venture strategy by framing the way a firm will operate and how it will function in achieving its goals (e.g., profitability, growth, innovation, social impact). However, scholars and practitioners have criticized the adoption of a too static perspective in the design and use of conventional Business Model representations. Such a static perspective prevents nascent entrepreneurs experimenting with their Business Models and, as a result, identifying the most effective strategies, especially in terms of business sustainability and profitability. In this paper, we argue that combining conventional Business Model schemas with System Dynamics modelling results in a strategy design tool that may overcome several limitations related to a static view of Business Model representation. Mapping the different key elements underlying value creation processes into a system of causal interdependencies – through the use of simulation – allows strategy analysts and entrepreneurs to experiment and learn how the business reacts to strategic and organizational changes in terms of performance, innovation and value creation. As such, Dynamic Business Models provide useful insights to strategy formulation and business venturing by capturing how critical Business Model elements interact to produce enduring competitive advantages over time.  相似文献   
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