Social media approaches to modeling wildfire smoke dispersion: spatiotemporal and social scientific investigations

Wildfires have significant effects on human populations, economically, environmentally, and in terms of their general well-being. Smoke pollution, in particular, from either prescribed burns or uncontrolled wildfires, can have significant health impacts. Some estimates suggest that smoke dispersion from fire events may affect the health of one in three residents in the United States, leading to an increased incidence of respiratory illnesses such as asthma and pulmonary disease. Scarcity in the measurements of particulate matter responsible for these public health issues makes addressing the problem of smoke dispersion challenging, especially when fires occur in remote regions. Crowdsourced data have become an essential component in addressing other societal problems (e.g., disaster relief, traffic congestion) but its utility in monitoring air quality impacts of wildfire events is unexplored. In this study, we assessed if user-generated social media content can be used as a complementary source of data in measuring particulate pollution from wildfire smoke. We found that the frequency of daily tweets within a 40,000?km² area was a significant predictor of PM2.5 levels, beyond daily and geographic variation. These results suggest that social media can be a valuable tool for the measurement of air quality impacts of wildfire events, particularly in the absence of data from physical monitoring stations. Also, an analysis of the semantic content in people’s tweets provided insight into the socio-psychological dimensions of fire and smoke and their impact on people residing in, working in, or otherwise engaging with affected areas.     

空气污染治理的地方政府角色研究——以北京市顺义区为例

公共事务现代经济学理论中的公共物品理论认为政府应成为公共物品的主要提供者,中外各国空气污染治理实践也都以政府为主导展开。空气污染治理成为我国政府目前进行生态文明建设需要解决的重要议题。以北京市顺义区政府为代表的地方政府在空气污染治理工作中表现出令人印象深刻的政策执行能力和公共事务管理能力,并在区域生态治理、保障辖区空气质量方面扮演关键角色,发挥重要作用。但是地方政府也面临缺乏与其他治理主体的联动、缺乏有效政策制定工具和治理手段单一等问题。     

新形势下能动类专业大气污染控制工程教改探索

“大气污染控制工程”是能源与动力工程类专业重要的专业课。为了深入切合专业设置的侧重与特色,结合新形势下能源动力类典型工科本科生培养要求和目标,从内容设置、教学方式尤其是工程课程设计和双语及全英教学方面进行了该课程教学改革的尝试和探索,以期对相近专业同类课程的教学改革起到参考作用。     

论夏商时期的时间意识

基于长期观察和实践,原始社会晚期已经萌生原始时间概念。商王朝时期,时间概念已非常丰富和成熟,并应用于季节记时、年月日记时以及时刻记时。夏商时间意识特征：一是具有季节变化的周期性色彩,并与农业活动和人们社会生活密切相关。二是已形成了较完整的体系和管理与运作制度,带有原始宗教色彩。三是开始出现了客观时间向主观心理时间的转换,对时间迟滞状态和时光飞逝现象的认识已经呈现。     

五道水库污染对延吉市饮用水的影响及其对策

新建的五道水库是延吉市主要的供水水源,其水质对市民身体健康和全市经济持续发展至关重要.然而,由于五道水库区存在自身潜在污染源和水库上游居民区的污染源,因此提出超前防治污染源,建立生态保护区,以保护水库生态系统,使之成为永久性优质水源.     

利用湿热空气处理繁殖无病毒无籽红江橙苗木的研究

国内外研究证明：利用４８ ～５０ ℃的湿热空气处理柑桔枝条６０ｍｉｎ ,可完全杀死枝条内的黄龙病病原类立克次体,然后嫁接繁殖无病毒苗木．但由于湿热空气处理对枝条的损伤,嫁接成活率很低．试验结果表明,湿热空气处理的相对湿度可明显提高嫁接成活率．另外,延长湿热空气处理时间对枝条的损伤明显小于由于提高处理温度对枝条的损伤,因此,为了保证脱毒效果,可适当延长处理时间,而不需提高处理温度．利用湿热空气处理枝条,采用预热处理,即逐渐提高处理的温度,以及处理完后,逐步降温,可提高嫁接成活率．特别注意湿热空气处理后的枝条,不能当天进行嫁接,应沙藏２４ｈ 后,开始嫁接     

采用气升式反应器葡萄糖母液流加发酵红曲色素的研究

以葡萄糖母液为原料 ,对在气升式生物反应器中流加发酵生产红曲色素进行了研究 ,建立了简单的数学模型控制流加 .结果表明 ,当总葡萄糖母液浓度为 1 50 g/L时 ,以 90 g/L初始葡萄糖母液开始发酵 ,当流加因子 K=0 .0 0 1 3时 ,变速流加发酵组的色素浓度比非流加发酵组的色价增加 32 % .     

The Bumpy Road to a Tobacco-Free Community: Lessons from Well City

Over 880 communities have put regulations in place to reduce or eliminate tobacco use in buildings used by the public. This study examines the experience of one such community—Well City, Ohio. The nonsmoker protection efforts in Well City help us identify and discuss eight important considerations affecting policy development and implementation: (1) anticipate community opposition, (2) identify and collaborate with a support network, (3) control the community hearing process, (4) anticipate outside interests, (5) recognize the potential for legal challenges, (6) address life with legal limbo, (7) start strong, and (8) watch the mix of politics and public health. Current clean indoor air efforts seem to focus on establishing coalitions and encouraging employers to voluntarily establish tobacco-free workplaces and restaurants. These efforts certainly need to continue but as a basic part of a comprehensive program which recognizes the importance and fosters the development of strong nonsmoker protection regulations developed at the local level by health boards, county boards of supervisors, and/or city councils.     

珠三角城市空气质量的时空变化特征及影响因素

珠江三角洲是我国人口、经济高度聚集的区域之一,环境问题凸显,城市空气质量备受关注。基于2002~2011年珠三角9城市空气污染指数,运用空间统计分析方法描述珠三角城市空气质量的时空分布特征,采用格兰杰因果检验探究珠三角地区城市间空气质量溢出特征,并结合灰色关联分析珠三角空气质量的影响因素。结果显示:珠三角2002~2011年空气质量有所好转,具有显著的季节性特征,冬季污染较严重,夏季污染较轻;空间上呈现出空气污染以广州为中心向四周递减的分布模式,并且存在城市间空气质量的相互影响效应,位于珠三角中部的广州和佛山的空气质量对东、南部的深圳和珠海空气质量产生影响;工业SO2排放量、人均绿地面积和城镇房屋施工面积是影响珠三角城市空气质量的主要因素。     

发电厂海勒式空冷系统的变工况特性

本文建立了海勒式空冷系统的数学模型，编制了该系统的变工况模拟程序，以２００ＭＷ海勒系统为例作了实时模拟计算，计算结果与实际运行数据相当接近，揭示了海勒系统变工况运行的基本特征．