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31.
随着我国经济的发展,电力对煤炭资源的需求以及对环境产生的污染问题已经越来越受到人们的关注。为研究电力——经济——环境系统的协调问题,从科技水平、管理水平、经济效益和协调水平四个方面建立了电力企业可持续发展评价指标体系。采用空间距离综合评价法对电力企业可持续发展能力进行了评价,结果证实:与理想点的差距越大,电力企业可持续水平越差。  相似文献   
32.
在武汉天兴洲大桥铁路江北引桥滠口左线引桥1#桥施工中,为满足施工现场混凝土运输的需要.采取以下措施:8-9#墩处上游附近搭设施工便桥1座;便桥桥面板采用2500×1000×200mm钢筋混凝土槽型板;纵向主梁采用8片H600×200mm型钢横向排列,且每两片一组用1cm厚铜板进行抱箍:每墩采用2片36a工字钢做横抬梁;便桥基础采用铜管排桩基础。经对纵梁、横抬梁、桥面板及基础铜管桩受力进行分析.检算合格,经实践证明以上措施及方案安全可行。  相似文献   
33.
We contribute to the debate on high-powered versus low-powered incentives in regulation by studying their heterogeneous impacts on different subpopulations, using data from the introduction of a high-powered prospective payment system (PPS) for hospital reimbursement in Germany. While no overall effect on quality or cost saving is found, our results support hypotheses drawn from an incentive and selection perspective: PPS reduces the length of stay of older relative to younger patients, of more severe relative to less severe cases, and in smaller relative to larger hospitals. Hospitals which adopted PPS earlier provide higher quality under PPS as proxied by the case-specific readmission rate. Our study also contributes to the health economic literature on hospital reimbursement as our data permits us to identify the treatment effect via different timings of adoption of PPS and to use a more accurate quality measure by following patients even when readmitted to other hospitals.  相似文献   
34.
王海宇  王小宁 《科技和产业》2023,23(12):210-217
为了提高过程质量监控效率和降低过程质量控制成本,针对过程质量特性分布未知情形,利用Burr分布近似未知分布,研究可变样本容量和抽样间隔(VSSI)的指数加权移动平均(EWMA)控制图的统计经济多目标优化设计问题。首先,建立基于Burr近似的未知分布VSSI EWMA图,采用平均产品长度、单位产品质量成本分别作为统计和经济指标,构造该图的统计经济多目标优化设计模型 。之后,采用NSGA-Ⅱ算法对模型进行算例求解和灵敏度分析。最后,将该方案与已有几种EWMA图设计方案比较。结果表明,在总体分布未知时,该方案在统计监控效率和过程监控成本两方面都要优于VSSI EWMA图的单一性设计,以及EWMA图多目标优化设计。  相似文献   
35.
本文参考Antrs et al(2012)方法,利用中国1997年、2002年、2007年、2012年和2017年投入产出表测度30个省份17个细分行业的产业链长度,并在此基础上分析服务外包对延伸产业链长度的作用。实证结果表明:第一,从整体上看,服务外包对我国产业链长度攀升具有显著促进作用,服务外包每提高10%,可以促进我国产业链长度提升062%。第二,从细分类型的服务外包看,交通仓储外包对产业链长度延伸的促进作用最大。第三,分地区研究发现,服务外包对中部地区产业链长度提升最大,其次是西部地区,东部地区最小。第四,分行业后发现,服务外包对制造业和服务业产业链长度均有提升作用,但是对服务业促进作用是制造业的近2.7倍。  相似文献   
36.
ABSTRACT

Water has been seen as a healing source of life for centuries. Even the placebo effect of thermal therapies increases consumers’ well-being. Especially with easy traveling options demand for thermal therapies are on the rise. Users of thermal therapies are mostly composed of seniors. Even though age groups in the senior market have heterogeneous needs, managers assume them to be homogenous. Measuring thermal tourism demand by the length of stay, this study analyzed the determinants affecting the length of stay of older thermal tourists. The length of stay is predicted to have been affected by age, purchasing power, physical distance, and seasonal preferences. Even though all of the above have an effect on the length of stay, we find that age is the main determinant deciding the duration. These results may serve as a starting point for policymakers and tourism managers to tailor strategies to increase income streams associated with length of stay.  相似文献   
37.
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   
38.
Using a research model based on customer value theory, this study investigates the determinants of customer post-purchase price comparison searches in the context of online price-matching guarantees (PMG). Data collected from 222 eligible respondents are tested against the proposed research model using partial least squares structural equation modeling (PLS-SEM). The results indicate two PMG characteristics, refund length and refund scope, influence utilitarian benefit (i.e., refund depth) and hedonic benefit (i.e., playfulness). These two benefits subsequently contribute to customer perceived value, which leads to price search intentions. This study pioneers the exploration of online PMGs and the determinants of customer post-purchase price search intentions. Several important theoretical and practical implications can be drawn from the findings to guide online retailers’ PMG strategies.  相似文献   
39.
Consumer-generated restaurant reviews are important sources in consumers’ purchase decisions. The purpose of this study is to explore the impact of emotional intensity on perceived review usefulness as well as the moderating effects of review length and reviewer expertise. Data from 600,686 reviews of 300 popular restaurants in the US were obtained from Yelp. Using a text mining approach and econometric analysis, empirical results show that (1) positive emotional intensity has a negative impact on perceived review usefulness, whereas negative emotional intensity has a positive impact on perceived review usefulness; (2) among the two most prevalent discrete negative emotions in online reviews (i.e., anger and anxiety), reviews expressing anger are more useful than those expressing anxiety; and (3) review length and reviewer expertise can moderate the effect of emotional intensity on perceived review usefulness.  相似文献   
40.
崔乃枭 《价值工程》2014,(23):126-128
研究了确定霍州煤电集团辛置矿310轨道巷松动圈的范围的方法,为的合理长度长度确定以及注浆加固围岩注浆孔深度的确定提供了数据基础。介绍了松动圈测定的基本原理和测试方法。  相似文献   
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