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随着经济的快速增长和改革的逐渐深入,我国重大突发事件屡见不鲜,事件突发性强、社会关注度高,且部分事件受天气制约因素大,因此做好决策气象保障工作对重大突发事件管理起着非常关键的作用;同时,其服务产品领导阅读率较高,关注度和重要性不可小觑。因此立足于业务实践,对国家级气象部门的重大突发事件应急决策气象服务进行总结、分析和探讨,旨在不断提升决策气象服务产品的质量,展现气象行业的重要性,更好地服务政府和人民。 相似文献
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麦秆酸预处理后与猪粪混合发酵提高产气量的效应研究 总被引:1,自引:0,他引:1
为了研究不同水平的酸处理对麦秆混合发酵过程中各指标变化的影响,本试验通过测定不同醋酸浓度、时间处理后的麦秆与猪粪混合厌氧发酵进程中还原糖、挥发性脂肪酸(VFA)含量,以及p H值变化和甲烷产量,探究各指标的关系并优化得出最佳醋酸处理组合,以期为酸预处理混合发酵实现高甲烷产量提供可靠的理论依据.结果表明,醋酸处理后的麦秆通过与猪粪混合发酵可明显提高甲烷单位产量,增幅为124.28%~207.40%.发酵过程中还原糖、VFA、p H值间相互影响.通过响应面法建立模型,得到醋酸处理的最优组合为浓度3.35%、时间6.75d,最大甲烷单位产量751.97 m L·g-1(以VS计). 相似文献
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Stefan Candefjord Helen Fagerlind András Bálint Claudia Wege Bengt Arne Sjöqvist 《Traffic injury prevention》2015,16(7):S190-S196
Objective: The aim of this study is to develop an on-scene injury severity prediction (OSISP) algorithm for truck occupants using only accident characteristics that are feasible to assess at the scene of the accident. The purpose of developing this algorithm is to use it as a basis for a field triage tool used in traffic accidents involving trucks. In addition, the model can be valuable for recognizing important factors for improving triage protocols used in Sweden and possibly in other countries with similar traffic environments and prehospital procedures.Methods: The scope is adult truck occupants involved in traffic accidents on Swedish public roads registered in the Swedish Traffic Accident Data Acquisition (STRADA) database for calendar years 2003 to 2013. STRADA contains information reported by the police and medical data on injured road users treated at emergency hospitals. Using data from STRADA, 2 OSISP multivariate logistic regression models for deriving the probability of severe injury (defined here as having an Injury Severity Score [ISS] > 15) were implemented for light and heavy trucks; that is, trucks with weight up to 3,500 kg and ??16,500 kg, respectively. A 10-fold cross-validation procedure was used to estimate the performance of the OSISP algorithm in terms of the area under the receiver operating characteristic curve (AUC).Results: The rate of belt use was low, especially for heavy truck occupants. The OSISP models developed for light and heavy trucks achieved cross-validation AUC of 0.81 and 0.74, respectively. The AUC values obtained when the models were evaluated on all data without cross-validation were 0.87 for both light and heavy trucks. The difference in the AUC values with and without use of cross-validation indicates overfitting of the model, which may be a consequence of relatively small data sets. Belt use stands out as the most valuable predictor in both types of trucks; accident type and age are important predictors for light trucks.Conclusions: The OSISP models achieve good discriminating capability for light truck occupants and a reasonable performance for heavy truck occupants. The prediction accuracy may be increased by acquiring more data. Belt use was the strongest predictor of severe injury for both light and heavy truck occupants. There is a need for behavior-based safety programs and/or other means to encourage truck occupants to always wear a seat belt. 相似文献
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针对影响油气管道安全运营的落石冲击问题,基于弹塑性力学、Cowper-Symonds本构模型和有限元方法,建立了球形落石冲击油气管道的计算模型,对管道动态响应过程进行了数值模拟。对冲击速度、落石半径、管道内压力和落石冲击位置进行了参数敏感性分析,研究了各参数对管道冲击变形的影响规律。结果表明:落石的冲击能量主要用于管道塑性变形;冲击过程中,落石与管道的接触区域由初始的椭圆斑逐渐变成了椭圆环;管道塑性变形随着冲击速度和落石半径的增大而增大,随内压和落石偏移度的增大而减小。该研究工作为油气管道的安全评价及防护工程的设计提供了参考依据,对保障油气安全运输具有重要的工程意义。 相似文献
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Planning,governance and rural futures in Australia and the USA: revisiting the case for rural regional planning 总被引:2,自引:0,他引:2
T.H. Morrison Marcus B. Lane Michael Hibbard 《Journal of Environmental Planning and Management》2015,58(9):1601-1616
Rural regions in post-industrial countries confront significant new challenges, particularly in relation to climate, biodiversity, unconventional resource development and energy. Yet at a time when the contours of these challenges are still being sketched, and preliminary, planned interventions undertaken, the practice of rural planning finds itself at a low ebb. We examine two ‘critical cases’, one each from Australia and the USA, to explore the issues and options for capacity of rural regional planning to surmount these new challenges. Our examination indicates the urgent need for a renewed discourse on rural regional planning. 相似文献
89.
Comparing Green and Grey Infrastructure Using Life Cycle Cost and Environmental Impact: A Rain Garden Case Study in Cincinnati,OH 总被引:1,自引:0,他引:1 下载免费PDF全文
Donald Vineyard Wesley W. Ingwersen Troy R. Hawkins Xiaobo Xue Bayou Demeke William Shuster 《Journal of the American Water Resources Association》2015,51(5):1342-1360
Green infrastructure (GI) is quickly gaining ground as a less costly, greener alternative to traditional methods of stormwater management. One popular form of GI is the use of rain gardens to capture and treat stormwater. We used life cycle assessment (LCA) to compare environmental impacts of residential rain gardens constructed in the Shepherd's Creek watershed of Cincinnati, Ohio to those from a typical detain and treat system. LCA is an internationally standardized framework for analyzing the potential environmental performance of a product or service by including all stages in its life cycle, including material extraction, manufacturing, use, and disposal. Complementary to the life cycle environmental impact assessment, the life cycle costing approach was adopted to compare the equivalent annual costs of each of these systems. These analyses were supplemented by modeling alternative scenarios to capture the variability in implementing a GI strategy. Our LCA models suggest rain garden costs and impacts are determined by labor requirement; the traditional alternative's impacts are determined largely by the efficiency of wastewater treatment, while costs are determined by the expense of tunnel construction. Gardens were found to be the favorable option, both financially (~42% cost reduction) and environmentally (62‐98% impact reduction). Wastewater utilities may find significant life cycle cost and environmental impact reductions in implementing a rain garden plan. 相似文献
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为了提高空气质量改善进程,2013 年国家发布了《大气污染防治行动计划》。本文基于空气污染与健康效益评估模型(BenMAP),对人口分布资料、大气污染与人体健康影响的暴露反应关系等进行了本土化修正,采用“支付意愿法”与“疾病成本法”相结合的方法,系统评估了《大气污染防治行动计划》实施后,PM2.5 污染变化引起的环境健康效益。研究结果表明,《大气污染防治行动计划》的实施将在一定程度上降低PM2.5 环境浓度,改善环境空气质量。如果《大气污染防治行动计划》空气质量目标全面实现,可以避免城镇8.9 万居民的过早死亡,减少12 万人次住院治疗以及941 万人次的门诊和急诊病例,实现的全国健康效益约为867 亿元/ 年,说明了《大气污染防治行动计划》实施的健康有益性。本文对政府部门开展污染损失评估及制定环境健康政策具有重要的参考价值。 相似文献