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1.
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
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在梳理国内外BIM采纳与扩散相关研究的基础上,从新制度主义理论出发,提出了水利水电工程组织场域并分析了其特征;进而运用技术-组织-环境(TOE)框架和匹配理论,分别讨论了水利水电工程组织场域BIM扩散的主要影响因素,形成一个整体的理论分析框架。分析表明,水利水电工程组织场域BIM扩散的影响因素主要包括:相对优势、兼容性和复杂性等技术因素,组织沟通、资源就绪度和高层领导支持等组织因素,以及制度环境、市场环境等环境因素。 相似文献
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Linda Harris Sophie Graham Sharon MacLachlan Alex Exuzides Saiju Jacob 《Journal of medical economics》2019,22(7):691-697
Aims: To examine healthcare resource utilization associated with refractory myasthenia gravis (MG) in England.Materials and methods: This was a retrospective cohort study of linked data from the Clinical Practice Research Datalink and the Hospital Episode Statistics database collected between 1997 and 2016. Included patients were ≥18?years of age at the index MG diagnosis. Patients with refractory MG were identified using an algorithm based on treatments received. Healthcare resource utilization since the index date was compared between refractory and non-refractory cohorts.Results: The study included 1149 patients with MG, of whom 66 (5.7%) were refractory. Sex and age at diagnosis did not significantly differ between the refractory and non-refractory cohorts. Rates of healthcare resource utilization per person-year were significantly higher (p?.05) for patients with refractory compared to non-refractory MG for GP visits, visits to other healthcare professionals, outpatient visits and inpatient hospitalization. Patients in the refractory cohort spent more total days hospitalized since the index visit than patients in the non-refractory cohort (median, 33 vs. 16?days [p?.0001]).Limitations: The algorithm for identifying refractory patients did not include clinical criteria. Also, treatments administered in hospitals or by specialists were not available in the databases.Conclusions: Patients in England with refractory MG more often visit healthcare providers, are hospitalized and visit an emergency room than patients with non-refractory MG. 相似文献
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地基处理技术是近年来我国房屋建筑工程施工中一种较常见的施工处理技术,多见于房屋建筑工程中的软土地基施工环节。通过以往的房屋建筑经验,如果直接在软土地基上进行建筑施工,地基区域软土很容易会影响房屋建筑工程的稳定性,所以,在针对这一部分软土区域的施工环节,需要针对拟施工的地基软土区域进行处理,提升其软土的稳定性。到目前,地基处理技术已经在我国房屋建筑工程施工中广泛应用,这一技术应用过程中存在的不足也逐渐凸显,如何针对这一技术的不足予以完善,以此提升地基处理技术对房屋建筑质量的积极影响,成为了现阶段房屋建筑地基基础施工质量提升的重要环节之一。 相似文献
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水源地突发水污染政府应急预留水量需求预测 总被引:1,自引:1,他引:0
近年来,随着工业化和产业化的快速发展,水源地突发水污染事件频发。为应对紧急情况下的水资源非常规需求,保障经济社会稳定发展,政府需要安排一部分应急预留水量。如何合理预测政府应急预留水量的规模是一个值得探讨的课题。提出了一种基于案例推理技术的政府应急预留水量需求预测方法,具体思路是:借助于案例库,利用主成分分析法从众多影响水源地突发水污染事件的因素中提取出两两不相关的因子,以此作为案例的特征属性,基于加权曼哈顿距离测算相似度,依此得到匹配案例,进而测算政府应急预留水量。以太湖流域常州地区水源地为例,进行政府预留水量需求量的预测与分析。该方法可以为政府应急预留水量的配置、储备等提供相关理论知识。 相似文献
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Assessing cost‐effectiveness when environmental benefits are bundled: agricultural water management in Great Barrier Reef catchments 下载免费PDF全文
John Rolfe Jill Windle Kevin McCosker Adam Northey 《The Australian journal of agricultural and resource economics》2018,62(3):373-393
Using economic analysis to prioritise improvements in environmental conditions is particularly difficult when multiple benefits are involved. This includes ‘bundling’ issues in agricultural pollution management, where a change in management action or farming systems generates multiple improvements, such as reductions in more than one pollutant. In this study, we conceptualise and compare two different approaches to analysing cost‐effectiveness when varying bundles of benefits are generated for a single project investment. Each approach requires data to be transformed in some way to allow the analysis to proceed. The index approach requires the transformation on the benefits side so that the effects of multiple pollutant changes can be combined into a measure for each project which can then be compared to costs. By comparison, the disaggregation approach requires the transformation on the costs side where costs for each project have to be apportioned across the different pollutants involved. The paper provides novel insights with an application to agricultural water quality improvements into the Great Barrier Reef in Australia, demonstrating that while both approaches are effective in prioritising projects by cost‐effectiveness, the disaggregation approach provides more insightful results and values that may be relevant for use as upper value guidelines in future project selection. 相似文献
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Philip S. Wells Anthonie W. A. Lensing Lloyd Haskell Bennett Levitan François Laliberté Michael Durkin 《Journal of medical economics》2018,21(6):587-594
Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment. 相似文献
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松嫩平原北部黑土区水土资源平衡效应研究 总被引:1,自引:0,他引:1
研究目的:分析松嫩平原北部黑土区在土地利用和农业气候资源变化条件下的水土资源平衡效应。研究方法:在傅抱璞假设理论的基础上,通过拟合参数ω回归方程求得实际蒸散量,以此来构建水分盈亏模型,分析水土资源平衡效应。研究结果:(1)1985—2015年,松嫩平原北部土地利用表现为湿地面积大幅度减少,水田和旱地面积不断增加;潜在蒸散量和气温具有较为明显的变化趋势,气温以0.27℃/10 a上升,潜在蒸散量以5.15 mm/a下降;(2)经过拟合参数ω方程求得实际蒸散量可以有效反映土地利用状况、地貌特征和土壤属性;(3)1985—2015年间总体的水分亏缺率均值是0.25、0.2、0.31和0.13,而土地利用的影响使严重缺水面积逐年增加,其增加量是总面积的1.59%,约是原有面积的2倍。研究结论:基于傅抱璞理论改进的参数ω能够提高地区实际蒸散量的估算精度,对区域水土平衡评价具有重要意义,为实现区域资源合理利用提供指导。 相似文献