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141.
[目的]东北地区大豆干旱严重,构建基于灾变过程的东北地区大豆干旱等级指标,分析研究区域大豆干旱时空分布特征,对大豆干旱灾害进行实时监测预警、区域防旱减灾具有重要意义。[方法]文章利用1961—2020年东北地区101个气象站点逐日气象资料、45个农业气象站的大豆发育期资料以及大豆历史灾情资料,通过历史灾情资料反演,基于水分盈亏指数并进行累计概率分布转换获得大豆干旱样本序列,采用K-S分布拟合检验拟合样本序列概率分布,通过t分布区间估计法确定指标等级阈值,并进行验证。在此基础上,分析大豆干旱时空变化特征。[结果](1)将大豆水分盈亏指数CD50,i=0.56作为大豆干旱过程初始判别值,以CD50,i≥0.56干旱过程持续日数(D)为主导因子,以CD50,i≥0.56逐日累加值(SDI)为辅助因子,构建了基于日尺度气象资料的东北地区大豆干旱等级指标,实现了干旱的动态化判识,指标验证结果显示与灾情记录等级完全符合的样本占全部样本的82.4%。(2)东北地区大豆每站平均总干旱频次最高的年份为1989年,达到1.51次/站,其次是...  相似文献   
142.
目的 寻找农业水土资源耦合研究热点、梳理研究发展历程、统筹和归纳研究体系,明晰未来研究发展方向和突破点,助力农业水土资源可持续利用。方法 文章通过定性与定量研究相结合,借助CiteSpace软件对1992—2022年农业水土资源耦合研究热点、发展历程进行初步分析,之后借助文献归纳法进一步综述研究体系。结果 研究聚焦于农业水土资源利用效率及效用,总体上经历了从土壤理化性质到水土资源优化配置、从小尺度作物种植到大尺度流域治理的发展历程,研究体系由3个研究基本面和6个研究基本点构成,研究基本面分别为水土资源匹配格局、水土资源利用过程、水土资源状态响应,即“格局—过程—响应”的农业水土资源耦合研究体系。结论 水土资源匹配格局方面需进一步明晰水土资源空间分异特征并加强二者物理交互过程和时空变异规律的研究,建议未来聚焦于识别水土资源配置差别并建立实践性的匹配等别标准;水土资源利用过程方面土地利用变化后水文过程响应研究尚待补充,建议未来可深入探索土地利用与水文过程的二元互馈机理;水土资源状态响应方面气候变化下需注意从气象指标入手探究农业生产中水土资源的关系,建议未来加强气候变化背景下低效利用问题的动态监测及预测模拟。  相似文献   
143.
This research examined philanthropy ad messages in terms of four key elements: philanthropy goal, beneficiary, expected fundraising impact, and how the suggested donation is appraised. A content analysis was carried out to systematically study ad messages from nonprofit organizations on the Philanthropy 400 list. Specifically, the frequency of appearance of each type of message elements was analyzed in terms of four theoretical concepts: regulatory focus (promotion vs. prevention goal), egoism/altruism (self vs. others as beneficiary), temporal orientation (present vs. future fundraising impact), and efficacy appraisal (self- vs. response-efficacy in how a donation is appraised). Since past research further suggests that persuasion may be enhanced when message elements are well matched in terms of “compatible fits,” this study further analyzed how the four message elements were combined in usage. The findings of this research show that while most nonprofit organizations actively utilized all four types of elements in their messages, the current practice did not follow the guidelines as would be suggested by compatible fits literature. In this respect, more research is needed to understand the discrepancy and provide better guidelines for future communication strategies in the nonprofit sector.  相似文献   
144.
Aims: This study investigated annual medical costs using real-world data focusing on acute heart failure.

Methods: The data were retrospectively collected from six tertiary hospitals in South Korea. Overall, 330 patients who were hospitalized for acute heart failure between January 2011 and July 2012 were selected. Data were collected on their follow-up medical visits for 1 year, including medical costs incurred toward treatment. Those who died within the observational period or who had no records of follow-up visits were excluded. Annual per patient medical costs were estimated according to the type of medical services, and factors contributing to the costs using Gamma Generalized Linear Models (GLM) with log link were analyzed.

Results: On average, total annual medical costs for each patient were USD 6,199 (±9,675), with hospitalization accounting for 95% of the total expenses. Hospitalization cost USD 5,904 (±9,666) per patient. Those who are re-admitted have 88.5% higher medical expenditure than those who have not been re-admitted in 1 year, and patients using intensive care units have 19.6% higher expenditure than those who do not. When the number of hospital days increased by 1?day, medical expenses increased by 6.7%.

Limitations: Outpatient drug costs were not included. There is a possibility that medical expenses for AHF may have been under-estimated.

Conclusion: It was found that hospitalization resulted in substantial costs for treatment of heart failure in South Korea, especially in patients with an acute heart failure event. Prevention strategies and appropriate management programs that would reduce both frequency of hospitalization and length of stay for patients with the underlying risk of heart failure are needed.  相似文献   
145.
Lee  Sang M.  Lee  DonHee 《Service Business》2020,14(1):1-22
Service Business - The Industry 4.0 era has brought a shift in consumers’ purchasing behaviors from traditional retailing to online and/or mobile channels, triggered by advanced digital...  相似文献   
146.
The service sector has become the most important part of the global economy. Thus, Service Business: An International Journal (SB) was launched in 2007 to deliver innovative studies that can provide resonating insights to researchers and practitioners in services. This study analyzed 311 articles published in SB during the past 10+ years (2007–2017) by conducting network text analysis (NTA). The published papers’ keywords link relations were analyzed to create network maps of research topics, ranging from traditional to emerging ideas of researchers. Influential research topics and their clusters were identified using centrality and community analyses. Research trends were identified for the first 5 years (Volume 1–5) and later years (Volume 6–11) separately through NTA. The results reveal interesting change in research topics over time. Common keywords of studies published in the first 5 years were: Service, Innovation, Customer, Strategy, Tourism, and Quality. The primary frequent keywords of articles published during 2012–2017 were: Customer, Quality, Satisfaction, Innovation, Mobile, and Technology. The results of the study shed valuable insights to the researchers and practitioners in the service sector. Applications of keyword network building and analysis methods provided in this study would be helpful to researchers who are interested in exploring trends of emerging new topics.  相似文献   
147.
This article develops a computational framework to analyze dynamic auctions and uses it to investigate the impact of information sharing among bidders. We show that allowing for the dynamics implicit in many auction environments enables the emergence of equilibrium states that can only be reached when firms are responding to dynamic incentives. The impact of information sharing depends on the extent of dynamics and provides support for the claim that information sharing, even of strategically important data, need not be welfare reducing. Our methodological contribution is to show how to adapt the experience-based equilibrium concept to a dynamic auction environment and to provide an implementable boundary-consistency condition that mitigates the extent of multiple equilibria.  相似文献   
148.
<正> 24年来,深圳经济特区依赖“以开放促改革,以改革促发展” 的独特成长道路,创造了持续高速增长的经济奇迹。外商投资经济不仅构成深圳经济特区重要的微观基础,而且外商投资作为对外开放的最重要内容,有力促动了经济特区的体制改革和经济社会发展。加入世贸后,我国根据对外经济贸易政策统一性原则所作出的承诺,使经济特区利用特殊的政策吸引外商投资的作法受到一定约束,虽然经济特区的一些特殊经济政策仍然可以保留,但必须转换思路,主要依靠先行优势和移民城市具有的大量战略性资产,参加跨国公司本土化,培育深圳经济特区核心竞争力,建成世界经济中心之一。  相似文献   
149.
With the rapid pace of economic integration, the productivity of a country depends not only on domestic R&D, but also on foreign R&D through technology diffusion across countries. The advancement of information technology (IT) has made the international transmission of knowledge faster and more efficient, providing an important channel for international R&D spillovers. This paper investigates three channels of international R&D spillovers: trade, FDI, and information technology. Applying panel cointegration and dynamic OLS analysis to the data for 21 OECD countries plus Israel during the period from 1981 to 1998, we find that bilateral trade remains an important conduit for international R&D spillovers. Although bilateral FDI is found to be positively related to international R&D spillovers, their impact on productivity growth is relatively small. We also find that the development of information technology has played a more important role in international R&D spillovers and productivity growth in recent years.  相似文献   
150.
我国上市公司中存在着先股权融资、后债权融资、最后内源性融资这一有悖于西方财务理论与实践的融资顺序。本文从直接动因和根源动因两方面予以剖析,并在公司治理、内部运行机制等方面提出改进建议,以期啄食顺序在我国上市公司中早日实现,使之更好地服务于我国企业的持续发展。  相似文献   
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