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11.
孙克威  李斌  单莉 《低温与特气》2011,29(6):10-15,25
结合目前国情,以青岛市某地区为例,介绍应用大型海水源热泵满足冬季区域供暖和夏季区域供冷的需求,阐述利用大型水源热泵系统实现区域供暖供冷的主要原理,将项目能源运行成本、环境收益与直燃溴化锂系统方案,传统锅炉房+冷水机组方案进行比较,从不同角度论证应用海水源热泵实现区域供暖供冷的可行性.  相似文献   
12.
从加大对建筑行业的综合监管,缓解市场过度竞争的局面;加强对建设单位行为的规范和监督,保障企业的合法权益;完善对中介机构的规范和监管机制,确保其执业行为的公平、公正等十个方面提出了提高当前中小建筑企业利润率的建议。  相似文献   
13.
Motivating dairy producers to financially invest in the improvement of their animals' comfort and welfare can pose some challenges, especially when financial returns are uncertain. Economic advantages for dairy producers associated with increased animal welfare are likely to come from either a premium paid for the milk or increased productivity. The aim of the current study was to evaluate the associations between measures of herd productivity and farm profitability and animal-, management-, and resource-based indicators of cow welfare and comfort. The cow welfare measures were collected during a cow comfort assessment conducted on 130 Canadian freestall dairy farms, including 20 using an automatic milking system. Herd productivity and farm profitability measures were retrieved or calculated from data collected by the regional dairy herd improvement programs, and included milk production and quality, longevity, and economic margins over replacement costs. Univariable and multivariable linear regression models were used to assess the associations between welfare indicators and productivity and profitability measures. Increased yearly corrected milk production was associated with reduced prevalence of cows with knee lesions [β = 7.40; 95% confidence interval (CI): 2.6, 12.2], dirty flanks (β = 26.9; 95% CI: 7.4, 46.5), and lameness (β = 11.7; 95% CI: 3.3, 20.1). The farms' economic margin per cow, calculated over replacement costs, was associated with the within farm average lying time standard deviation (β = ?7.2; 95% CI: ?12.7, ?1.7), percent of stalls with dry bedding (β = 6.4; 95% CI: 1.4, 11.4), and prevalence of cows with knee lesions (β = ?5.1; 95% CI: ?8.9, ?1.3). Some of the relationships found were complex, including several interactions between the animal-, management-, and resource-based measures. Overall, the results suggest that improved cow comfort and welfare on freestall farms is associated with increased herd productivity and profitability, when the latest is calculated by the margins over the replacement costs.  相似文献   
14.
The purpose of this study is to develop a modification of the model developed by Chen and Zhu in 2004. Calculating stage and overall efficiencies precisely and consistently has become a major challenge of the two‐stage DEA model. However, most other models do not calculate the optimality of intermediates. Although the model developed by Chen and Zhu measures the optimality of intermediates, the calculated efficiency scores still have some shortfalls. The modified model, named the hybrid two‐stage DEA model, fills the gap between calculating the optimality of intermediates and the consistency of overall efficiency scores. In addition to obtaining an accurate measurement for the optimality of intermediates, the model confines efficiency scores to a range from zero to one (a ratio efficiency score). In an empirical evaluation, we use data from 64 medical manufacturing firms to test the performance of the hybrid model and offer recommendations for the industry.  相似文献   
15.
The effects of a rural roads programme depend on labour mobility, how the programme is financed, and agglomeration economies. If financed by a rural poll tax and cross-price effects and agglomeration economies are sufficiently small, the wage will rise, with some return migration. Taxes on trade act as countervailing distortions, yielding urban households some relief. Rural-urban commuting promotes the exploitation of agglomeration economies; taxes on international trade are then inferior to a poll tax. The change in the value, at producer prices, of the rural sector's net supply vector can be a poor measure of the programme's social profitability.  相似文献   
16.
文章选取企业盈利能力作为企业财务预警指标,运用粒子群优化算法,对样本进行指标分析,得出企业财务预警模型的分析结论,对企业经营决策起到重要的参考和指导性作用。  相似文献   
17.
中国建筑与房地产企业归核化经营收益能力研究   总被引:1,自引:0,他引:1  
本文选取了我国沪深两市1999年之前上市、至2003年未退市的建筑与房地产业中实施归核化经营的27家A股上市公司作为研究样本,以改进的Jacquemin-Berry熵值测量法度量企业的归核化程度,并采用两种非参数检验的方法对样本企业归核化前后的收益能力进行了检验分析和相关性考察.得出的基本结论是,我国建筑与房地产业中的多业务企业,在实施归核化经营后,其收益能力获得了显著的提升,归核化经营之后的企业收益能力显著优于归核化之前的收益能力,并且企业收益能力的提升幅度与其归核化程度之间呈现出显著的正相关关系.  相似文献   
18.
针对目前国内建筑企业项目成本控制的现状,深入分析其存在的问题,并提出了旨在改善和提高施工企业成本控制能力和管理水平的相关对策.  相似文献   
19.
通过对全球55家上市铜铁公司的财务、营运状况、企业的获利能力、投资回报、偿债能力的分析,得出了在原料丰富地区的企业的获利能力很强的结论。因此,炼钢原料价格的大幅上涨影响着钢铁企业的经营战略及未来发展方向,保证上游炼钢原料稳定供应,以及向下游加工延伸,贴近终端消费市场,已经成为钢铁企业的当务之急。  相似文献   
20.
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