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为从更微观角度分析人群疏散过程中疏散行为及路网设计对疏散效果的影响,基于腾龙芳烃(漳州)有限公司“4·6”爆炸着火重大事故,构建多智能体人群应急疏散模型,模拟人群中个体群组、惯性、就近、从众、信息传播的行为决策及相互交互影响。结果表明:群组行为会严重影响应急疏散效果,在疏散路网两端避难所附近会出现明显拥堵现象,在疏散路网设计和避难所选择时,应尽可能避免出现极端汇流路段或节点;在应急培训中,应告知群众减少群组行为。研究结果可为人群应急疏散提供借鉴。 相似文献
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Fouling behavior along the length of membrane module was systematically investigated by performing simple modeling and lab-scale experiments of forward osmosis (FO) membrane process. The flux distribution model developed in this study showed a good agreement with experimental results, validating the robustness of the model. This model demonstrated, as expected, that the permeate flux decreased along the membrane channel due to decreasing osmotic pressure differential across the FO membrane. A series of fouling experiments were conducted under the draw and feed solutions at various recoveries simulated by the model. The simulated fouling experiments revealed that higher organic (alginate) fouling and thus more flux decline were observed at the last section of a membrane channel, as foulants in feed solution became more concentrated. Furthermore, the water flux in FO process declined more severely as the recovery increased due to more foulants transported to membrane surface with elevated solute concentrations at higher recovery, which created favorable solution environments for organic adsorption. The fouling reversibility also decreased at the last section of the membrane channel, suggesting that fouling distribution on FO membrane along the module should be carefully examined to improve overall cleaning efficiency. Lastly, it was found that such fouling distribution observed with co-current flow operation became less pronounced in counter- current flow operation of FO membrane process. 相似文献
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森林生态系统土壤呼吸时空异质性及影响因子研究进展 总被引:5,自引:0,他引:5
土壤呼吸是全球碳循环的一个重要流通途径,是大气CO2的重要来源之一,是陆地碳循环的重要环节,对温室气体的排放产生直接影响,且关系到科学把握全球变化背景下CO2的排放动态,在全球碳收支中占据重要地位,越来越受到各国学者的广泛关注。在全球变化背景下研究土壤呼吸的时空异质性及其影响因子,可为探索陆地生态系统在碳循环方面的碳源/碳汇功能和揭示“碳失汇之迷”,以及减缓气候变暖等方面提供有力的依据。作为一个复杂的生物学与生态学过程,土壤呼吸受到气候、生物以及非生物等因子的影响而呈现时空异质性,并随着各种干扰因子影响的增强,人为因素的作用亦越来越大,该文阐述了森林生态系统土壤呼吸作用的时空动态变化规律、并探讨了影响土壤呼吸速率的各种影响因子,剖析了导致土壤呼吸时空异质性的影响因子,指出自然因子、生物因子和干扰因子共同驱动着土壤呼吸的时空动态变化。并对森林生态系统土壤呼吸作用的模型模拟方面的研究进展进行了综述。最后讨论了森林土壤呼吸时空异质性研究中存在的相关问题,同时提出了今后土壤呼吸研究中应关注的问题,同时对森林生态系统土壤呼吸时空异质性及影响因子的研究方向进行了展望。 相似文献
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ADMS模型解析城区总悬浮颗粒物来源 总被引:1,自引:1,他引:1
以污染源排放数据为基础,应用ADMS-城市扩散模型模拟分析了鞍山市尘各污染源对空气环境质量的贡献。结果表明,来自污染源的浓度贡献值占总量的52%;二次尘及外来尘浓度贡献占48%;矿山开采二次尘的浓度贡献占16%;鞍钢炼铁厂的浓度贡献占19.6%;鞍钢化工总厂浓度贡献占5.6%;供暖锅炉浓度贡献占9.3%。低、中、高架源浓度贡献百分比分别为68.1%、29.0%、2.9%。低架源吨排放量浓度贡献为高架源的2.4倍。 相似文献
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基于田间原位测定结果,作者建立了不同水分管理方式下稻田N2O排放估算的统计模型.在模型验证和输入参数检验的基础上,本研究应用模型估算了20世纪50~90年代我国稻田水稻生长季N2O直接排放量.结果表明,由于水稻种植面积和氮输入量的增加、以及水分管理方式的变化,稻田N2O-N季节排放量从20世纪50年代平均每年9.55 Gg增加到了90年代每年32.26 Gg,同期伴随着水稻单产的增加.在20世纪50~90年代间,我国水稻生产的N2O-N排放量以平均每10 a 6.74 Gg的速度递增.20世纪50年代和90年代稻田N2O-N季节排放通量平均分别为0.32 kg·hm-2和1.00 kg·hm-2,相当于季节氮输入总量的0.37%和0.46%.本研究模型估算50~90年代间稻田N2O季节排放量的不确定性为59.8%~37.5%.就全国稻田的不同种植区域而言,长江中下游地区稻田水稻生长季N2O排放量占全国稻田N2O排放总量的51%~56%.20世纪90年代水稻生长季N2O排放量约占我国农田N2O年总排放量的8%~11%.相对于旱地作物而言,过去几十年水稻生产的发展在很大程度上减缓了我国农业生产的N2O排放.然而,随着水稻生产中节水灌溉的推广和氮肥施用量的增加,我国稻田N2O季节排放量预计将相应增加. 相似文献
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Yen-Ping Peng Kang-Shin Chen Hsin-Kai Wang Chia-Hsiang Lai Ming-Hsun Lin Cheng-Haw Lee 《环境科学学报(英文版)》2011,23(5):790-797
Ozone sensitivity was investigated using CAMx simulations and photochemical indicator ratios at three sites (Pingtung City, Chao-
Chou Town, and Kenting Town) in Pingtung County in southern Taiwan during 2003 and 2004. The CAMx simulations compared
fairly well with the hourly concentrations of ozone. Simulation results also showed that Pingtung City was mainly a volatile organic
compounds (VOC)-sensitive regime, while Chao-Chou Town was either a VOC-sensitive or a NOx-sensitive regime, depending on
the seasons. Measurements of three photochemical indicators (H2O2, HNO3, and NOy) were conducted, and simulated three transition
ranges of H2O2/HNO3 (0.5–0.8), O3/HNO3 (10.3–16.2) and O3/NOy (5.7–10.8) were adopted to assess the ozone sensitive regime at
the three sites. The results indicated that the three transition ranges yield consistent results with CAMx simulations at most times at
Pingtung City. However, both VOC-sensitive and NOx-sensitive regimes were important at the rural site Chao-Chou Town. Kenting
Town, a touring site at the southern end of Taiwan, was predominated by a NOx-sensitive regime in four seasons. 相似文献
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松花江流域水污染防治规划决策支持系统构建与应用 总被引:1,自引:0,他引:1
采用SOA C/S架构,按照数据层、应用层和表现层的规范设计开发了松花江流域水污染防治规划决策支持系统。系统的数据层包括基础地形数据、水文数据、重点污染源监测数据、水质监测数据、气象数据以及经济效益数据等。应用层包括数据处理和分析、GIS查询分析服务等功能应用。表现层包括模型模拟结果展示、决策支持应用展示等。该系统为松花江流域的水环境管理提供了实用的工具。通过流域水环境形势诊断、流域水质模拟预测两个子系统,模拟了2011—2014年松花江流域水环境质量的变化情况,对比了"十二五"与"十三五"期间嫩江流域水质的改善效果,为决策者制定流域环境管理措施和方案提供有力支持。 相似文献