超低空航拍技术在输变电环评工作中的应用研究

分析了环评工作中收集的影像资料存在的问题，提出了超低空航拍的解决方法。通过对比分析，选择了多旋翼无人机作为超低空航拍平台。该设备具有携带方便，飞行稳性的优点。从实际应用效果来看，基于该技术获得的影像信息含量全面、工作效率高、评价结果更客观可信，为提高环评工作质量提供了一个可靠的技术方案。     

2014年北京市CO浓度水平和时空分布

对北京市地面监测站点的CO浓度进行分析，探讨其浓度水平、变化趋势和时空分布特征。2014年春、夏、秋、冬四季北京市CO平均浓度分别为1.06、0.87、1.34、2.17 mg/m³。CO浓度均呈双峰型变化，第一个峰值出现在07：00-09：00，主要由交通早高峰的排放引起；第二个峰值出现在23：00左右，主要受交通晚高峰排放和夜间边界层高度降低的挤压效应的共同影响。从空间分布来看，全年整体呈现南高北低的分布特征，尤其是秋、冬季较为明显，体现了工业布局和区域传输对CO的影响。从全年来看，湿度对CO浓度的影响最大。对2014年冬季北京市的一次高CO浓度分析结果表明，此次过程是由本地排放和区域传输共同造成的，气象要素中地面气压对CO浓度影响最大。     

冷空气在北上台风“利奇马”致灾暴雨中的作用分析

利用NCEP逐6 h再分析资料、地面加密观测、探空、雷达资料,分析得出“利奇马”致灾暴雨是在长时间稳定维持的天气尺度环流背景下形成的。冷空气在降水所起的作用表现在:(1)长时间维持的弱冷空气与偏南暖湿气流交汇形成了边界层辐合线,辐射升温和暖湿气流的输送加大了辐合线两侧的温度和露点梯度,在高温高湿的有利环境下,对流在辐合线附近强烈发展。(2)高空槽后冷空气由“利奇马”环流西北侧渗入,先后形成3个冷平流中心,分别对应3个阶段的降水。(3)冷暖空气在降水区的持续辐合抬升作用增强了降水,最强降水时段发生在锋区垂直方向坡度最大的时段。(4)水平锋生有利于水汽输送和辐合抬升,垂直锋生有利于对流不稳定能量的累积和触发。冷空气形成的水平辐合和抬升造成大范围上升运动,使得锋生和垂直锋消同时存在,最强降水时段发生在水平锋生最强的时段。     

大气细颗粒物在线源解析方法研究进展

基于对国内外关于PM2.5化学组分特征、二次气溶胶生成机理、源解析模型的研究综述,引入实现PM2.5在线源解析的2种可能方法,即气溶胶质谱+解析算法与3类化学组分组合观测+受体模型。重点阐述了气溶胶质谱及在线水溶性离子、EC/OC和金属元素仪器的应用研究现状,并分析了不同仪器测定结果的可靠性、优势及缺陷,在此基础上提出加强城市尺度的大气化学二次反应机理及关键技术参数研究、大气颗粒物化学组分连续观测应用于在线源解析的研究、基于多种信息来源和技术手段的在线源解析方法集成研究等建议。     

“T”型地铁换乘站多点火灾工况下综合火灾危险性研究

为探究大型地铁站多线路火灾场景中的综合危险性，采用火灾动力学软件FDS构建“T”型换乘站全尺寸模型，对不同火源位置、不同火源功率以及是否开启地铁排烟风机等12组工况进行数值模拟；采用性能化方法确定可用疏散时间，并通过综合火灾风险评估方法计算各工况总安全指数。结果表明:1号线站厅层和2号线站台层双点火灾为最不利火灾场景；1号线站台层和2号线站厅层双点火灾为相对安全火灾场景；火源功率的增大会增加地铁火灾危险性，但不同火源位置工况中的安全指数变化趋势相似；排烟模式开启前，1号线站厅层火灾会导致较大的火灾危险性；排烟模式开启后，地铁总安全指数显著上升且安全指数变化趋势改变，此时2号线站台层火灾会导致较大的火灾危险性。     

Social network theory in the behavioural sciences: potential applications

Social network theory has made major contributions to our understanding of human social organisation but has found relatively little application in the field of animal behaviour. In this review, we identify several broad research areas where the networks approach could greatly enhance our understanding of social patterns and processes in animals. The network theory provides a quantitative framework that can be used to characterise social structure both at the level of the individual and the population. These novel quantitative variables may provide a new tool in addressing key questions in behavioural ecology particularly in relation to the evolution of social organisation and the impact of social structure on evolutionary processes. For example, network measures could be used to compare social networks of different species or populations making full use of the comparative approach. However, the networks approach can in principle go beyond identifying structural patterns and also can help with the understanding of processes within animal populations such as disease transmission and information transfer. Finally, understanding the pattern of interactions in the network (i.e. who is connected to whom) can also shed some light on the evolution of behavioural strategies.     

Roads and Landscape Pattern in Northern Wisconsin Based on a Comparison of Four Road Data Sources

Abstract:  Roads are important components of landscapes; they fragment habitat, facilitate invasive species spread, alter hydrology, and influence patterns of land use. Previous research on the ecological impacts of roads may have underestimated their effect because currently available sources of road data do not include the full road network. We compared differences in road density and landscape pattern among U.S. Census Bureau TIGER line files, U.S. Geological Survey 1:100,000-scale digital line graphs, and U.S. Geological Survey 1:24,000-scale digital raster graphics in northern Wisconsin to road data derived from 1:40,000-scale digital orthophotos. Road density measured from digital orthophotos (2.82 km/km²) was significantly greater than that of digital raster graphics (1.62 km/km²) and more than double that of digital line graphs (1.21 km/km²) and TIGER (1.27 km/km²) data. The increased road densities in raster graphics and orthophoto data were mainly due to the addition of minor roads. When all roads were used to define patch boundaries, landscape metrics produced with orthophoto data showed significantly greater levels of fragmentation than those based on line or raster graphics. For example, maximum patch size was 1074 ha and total edge was 109 km for line graphs, compared with 686 ha and 211 km for orthophoto data. Roads are missing in commonly used data, primarily because mapping standards systematically exclude minor roads. These standards are not ecologically based and may result in false assumptions about the ecological effects of roads. We recommend that future studies take special consideration of the completeness of road data and consider whether all ecologically relevant roads are included.     

天津市机动车污染评估方法

依据城市机动车空气污染评价方法确立了天津市空气污染物机动车污染的评价体系。该评价体系具有准确性、先进性和实用性，采用科学的方法估算天津市城区机动车排气污染物的排放浓度及总量对环境空气污染的分担率。科学地给出了天津市现阶段机动车污染的现状及发展趋势，为环境保护决策提供了科学依据。     

Mark-recapture estimators for dual frame population size of prominent nesting structures: the effect of uncertain detection probability

The combined mark-recapture and line transect sampling methodology proposed by Alpizar-Jara and Pollock [Journal of Environmental and Ecological Statistics, 3(4), 311–327, 1996; In Marine Mammal Survey and Assessment Methods Symposium. G.W. Garner, S.C. Amstrup, J.L. Laake, B.F.J. Manly, L.L. McDonald, and D.C. Robertson (Eds.), A.A. Balkema, Rotterdam, Netherlands, pp. 99–114, 1999] is used to illustrate the estimation of population size for populations with prominent nesting structures (i.e., bald eagle nests). In the context of a bald eagle population, the number of nests in a list frame corresponds to a pre-marked sample of nests, and an area frame corresponds to a set of transect strips that could be regularly monitored. Unlike previous methods based on dual frame methodology using the screening estimator [Haines and Pollock (Journal of Environmental and Ecological Statistics, 5, 245–256, 1998a; Survey Methodology, 24(1), 79–88, 1998b)], we no longer need to assume that the area frame is complete (i.e., all the nests in the sampled sites do not need to be seen). One may use line transect sampling to estimate the probability of detection in a sampled area. Combining information from list and area frames provides more efficient estimators than those obtained by using data from only one frame. We derive an estimator for detection probability and generalize the screening estimator. A simulation study is carried out to compare the performance of the Chapman modification of the Lincoln–Petersen estimator to the screening estimator. Simulation results show that although the Chapman estimator is generally less precise than the screening estimator, the latter can be severely biased in presence of uncertain detection. The screening estimator outperforms the Chapman estimator in terms of mean squared error when detection probability is near 1 wheareas the Chapman estimator outperforms the screening estimator when detection probability is lower than a certain threshold value depending on particular scenarios.     

石材废水处理工程实例

介绍了石材废水集约化处理的一个成功实例,分析、总结了混凝沉淀法处理石材废水的可行性及注意事项,并通过比较得出石材废水集约化处理较分散治理具备明显优势的结论.