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61.
基于多目标优化与综合评价的海绵城市规划设计   总被引:1,自引:0,他引:1  
海绵城市源头减排设施已被广泛应用于城市雨水径流削减与污染控制,但仍缺乏一种综合评价方法来实现其科学规划设计.本研究构建了一种基于多目标优化与综合评价相耦合的海绵城市规划设计方法,以建设成本、雨水综合径流系数、污染物综合控制率为目标函数,以源头减排设施建设规模和海绵城市径流控制指标作为边界条件,建立基于快速分类的非支配遗传算法(NSGA-Ⅱ)的多目标优化模型;然后结合层次分析法对优化解集进行综合指标评价,得出最优化设计方案.利用该方法以研究区A为案例,构建了一套建设成本最小化、水文水质效益最大化的设计方案,并通过海绵城市建设前后的暴雨洪水管理模型(SWMM),评估最优化方案的降雨径流控制与径流污染控制效果.研究结果表明,海绵城市建设能大幅削减雨水径流量,年径流总量控制率达70.1%;雨水峰值流量削减率超过40%,同时延后径流峰值出现时间;有效降低雨水径流污染,研究区各类污染物综合削减率均超过30%.本文提出的多目标优化与综合评价方法,能够基于特定的目标与需求,针对性提出适合区域发展的海绵建设方案,为海绵城市规划设计提供技术支持.  相似文献   
62.
防渗型生物滞留中试系统降雨径流水质与三维荧光特征   总被引:1,自引:1,他引:0  
林修咏  王书敏  李强  谢云成 《环境科学》2018,39(10):4539-4546
构建了两套防渗型生物滞留中试系统,在2017年3~4月期间,跟踪监测了系统在低温小强度降雨条件下的径流水质特点,并同步分析了降雨径流的三维荧光光谱特征.系统降雨径流水质监测结果表明,经系统净化后,出水污染物浓度波动较小,对NH_4~+-N和TP均有相对稳定的去除效率,可分别达到78.38%~95.03%和72.04%~76.04%.荧光光谱特征分析表明,生物滞留系统出水中的主要溶解性有机物(dissolved organic matters,DOMs)为蛋白类物质和类腐殖质物质,主要来自生物或水生细菌代谢物;系统对于Ⅰ区、Ⅱ区蛋白类荧光有机物和类富里酸具有较好的去除效果,去除率可分别达到57.33%~61.30%、29.82%~31.28%和35.55%~43.16%.径流水质与DOMs相关性分析表明,系统径流出水中的TN、TP和TOC均与芳香类蛋白质含量呈显著正相关关系,而NO_3~--N和NH_4~+-N与芳香类蛋白质含量呈显著负相关关系;TN浓度均与Ⅳ区DOMs(微生物代谢产物)和V区DOMs(类胡敏酸)呈显著负相关关系.  相似文献   
63.
通过分析近年来生物滞留设施在土壤介质、气候与热冲击、生物多样性、生命周期成本等方面的研究内容得到,优化土壤介质可提高系统的处理性能。增加模型的兼容性与输入端控制可提高模型预测的准确性。小规模设施耐热冲击性能较好。生物滞留设施相比草坪、花园有更丰富的生物多样性,利用植物根系与生物多样性增强设施的性能还有待研究。通过主动性控制指导、加强施工段控制可降低设施的周期成本,成本模型预测的准确性还需加强基础资料的收集与资源的共享。  相似文献   
64.
Facilities life extension has caught the attention among the capital-intensive industries, like oil and gas. By extending the life cycle of the industrial assets, a wide range of benefits is obtained, comparing with other life ending management strategies. This article first contextualizes the implementation of the life extension concept in the oil and gas industry, showing global data about life extension. Despite the importance of the ageing process, due to its great economic impact and the risk it poses to the production sector, regulatory entities, even in countries more advanced in that sector or that have already experienced the extension process, developed only superficial material about the topic without defining a structured methodology for the assessment of the possibility of useful life extension. The available references do not allow a comprehensive analysis of that possibility, which highlights the importance the methodology proposed. Thus, this article proposes a guideline for the life extension process management, strengthening a framework containing the main evaluation stages, aiming to facilitate the analysis of issues related to ageing and to support the decision-making process. Lastly, real case studies regarding current life extension processes submitted to the Brazilian regulatory body were evaluated against the proposed framework stages, evidencing their lack of necessary details to support the decision-making. Upon the realization that the real cases identified do not allow for the assessment of the contribution and adequacy of the proposed framework in its entirety, the same was also applied to a hypothetical case. The latter was developed based on facts reported by a major operator in Brazil. The result was the determination that the use of the proposed methodology transformed the assessment of the possibility of life extension into a systematic and transparent process, leading to easier and better-founded decision-making procedures, and improving the management of the asset during its extended life.  相似文献   
65.
National reports along with numerous statewide studies indicate that the physical infrastructure of American schools is crumbling. At the same time there is emerging evidence that school building quality matters for children's academic achievement. We integrate two separate literatures that have demonstrated that low school building quality as well as high rates of student mobility each contribute to reduced academic achievement by showing that these two variables statistically interact. Elementary school children in 511 New York City public schools have lower achievement scores if they attend schools of poor structural quality and with high rates of student mobility. The significant main and interactive effects of school building quality and student mobility on standardized test scores occur independently of socioeconomic and racial composition of the school.  相似文献   
66.
The emission concentrations of several chlorofluorocarbons (CFCs) were measured from a municipal waste treatment facility (located in Seoul, Republic of Korea) to investigate the emission characteristics of CFCs in the urban environment. To this end, a total of five CFCs (CFC-10, CFC-11, CFC-20, CFC-30, and CFC-113) were analyzed by the thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method. The results of this study indicate that the formation of CFC-11 (8.21 ± 1.68 ppb in spring) and CFC-20 (3.92 ± 3.93 ppb in spring) proceeded very actively within the facility. Moreover, CFC-113 was also found in relatively high concentrations (3.34 ± 1.31 ppb in spring) in the treatment facility. Unlike other CFCs, CFC-10 was observed mainly at ambient (and reference) locations and one point inside the treatment facility. In conclusion, emissions of some important CFCs are a prominent process, as they were measured either frequently or abundantly both in winter and spring. It is further indicated that certain CFCs (like CFC-11 and CFC-30) are subject to highly significant seasonal variations.  相似文献   
67.
Medical isotope production facilities (MIPF) have recently been identified to emit the major part of the environmental radioxenon measured at many globally distributed monitoring sites deployed to strengthen the radionuclide component of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification regime. Efforts to raise a global radioxenon emission inventory revealed that the yearly global total emission from MIPF’s is around 15 times higher than the total radioxenon emission from nuclear power plants (NPP's).Given that situation, from mid 2008 until early 2009 two out of the ordinary hemisphere-specific events occured:1) In the Northern hemisphere, a joint temporary suspension of operations of the three largest MIPF's made it possible to quantify the effects of the emissions related to NPP’s. The average activity concentrations of 133Xe measured at a monitoring station close to Freiburg, Germany, went down significantly from 4.5 ± 0.5 mBq/m3 to 1.1 ± 0.1 mBq/m3 and in Stockholm, Sweden, from 2.0 ± 0.4 mBq/m3 to 1.05 ± 0.15 mBq/m3.2) In the Southern hemisphere the only radioxenon-emitting MIPF in Australia started up test production in late November 2008. During eight test runs, up to 6.2 ± 0.2 mBq/m3 of 133Xe was measured at the station in Melbourne, 700 km south-west from the facility, where no radioxenon had been observed before, originating from the isotopic production process.This paper clearly confirms the hypothesis that medical isotope production facility are at present the major emitters of radioxenon to the atmosphere. Suspension of operations of these facilities indicates the scale of their normal contribution to the European radioxenon background, which decreased two to four fold. This also gives a unique opportunity to detect and investigate the influence of other local and long distance sources on the radioxenon background. Finally the opposing effect was studied: the contribution of the start-up of a renewed radiopharmaceutical facility to the build up of a radioxenon background across Australia and the Southern hemisphere.  相似文献   
68.
This research investigated the under-explored area of safety in multi-purpose recreation facilities (MPRFs). Facility managers and other managerial staff (key informants) from four MPRFs in Victoria, Australia participated in semi-structured interviews. Safety was considered important from Occupational Health and Safety (OH&S), business viability and legal liability perspectives but not from a health promotion or public health point of view. Most implemented injury prevention measures required gymnasium and pool staff or users to change their behaviours. Awareness of safety standards was higher for some operational areas (e.g. aquatics, child-care) than others (e.g. gymnasium, group fitness activities). Key informants struggled to keep abreast of legislation changes and they relied on commercial, regulatory, and industry information sources rather than evidence of best practice. Reported factors influencing safety in MPRFs were classified into three types: internal (e.g. training, culture); external (e.g. weather, demographic change); and governance (e.g. insurance, industry standards). Comprehensive, relevant and accessible industry safety standards, which focus not only on OH&S but equally on health promotion principles and public health perspectives linked to injury prevention, are required. Training is needed to reflect these broader and equally important perspectives. Health/injury, fitness/recreation and insurance sector links should be improved to ensure a consistent, sustainable approach to safety.  相似文献   
69.
The origin of a series of atmospheric radioxenon events detected at the Comprehensive Test Ban Treaty Organisation (CTBTO) International Monitoring System site in Melbourne, Australia, between November 2008 and February 2009 was investigated. Backward tracking analyses indicated that the events were consistent with releases associated with hot commission testing of the Australian Nuclear Science Technology Organisation (ANSTO) radiopharmaceutical production facility in Sydney, Australia. Forward dispersion analyses were used to estimate release magnitudes and transport times. The estimated 133Xe release magnitude of the largest event (between 0.2 and 34 TBq over a 2 d window), was in close agreement with the stack emission releases estimated by the facility for this time period (between 0.5 and 2 TBq). Modelling of irradiation conditions and theoretical radioxenon emission rates were undertaken and provided further evidence that the Melbourne detections originated from this radiopharmaceutical production facility. These findings do not have public health implications. This is the first comprehensive study of atmospheric radioxenon measurements and releases in Australia.  相似文献   
70.
油气生产过程中集输设施安全管理问题研究   总被引:2,自引:0,他引:2  
针对油气生产中集输设施安全问题导致的油气泄漏引发的问题,以系统的方法分析其观念、技术、方法对集输设施管理的影响。围绕石油企业降本增效和可持续发展战略目标,从投资、建设、管理、养护各环节,管理体制、运行机制、管理方式等各方面系统研究,通过明确职能、落实责任、制定标准、严格程序、科学奖惩、强化管理等手段,从而树立正确管理理念,完善设施投入机制、监督考核机制、激励约束机制,强化企业管理基础工作等方面,提出与该系统工艺流程相适应的管理模式和方法,以管理优化保障工艺优化,延长设施使用寿命,提高系统运行效率,确保安全生产。  相似文献   
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