Neural network forecasting of air pollutants hourly concentrations using optimised temporal averages of meteorological variables and pollutant concentrations

The new method for the forecasting hourly concentrations of air pollutants is presented in the paper. The method was developed for a site in urban residential area in city of Zagreb, Croatia, for four air pollutants (NO₂, O₃, CO and PM₁₀). Meteorological variables and concentrations of the respective pollutant were taken as predictors. A novel approach, based on families of univariate regression models, was employed in selecting the averaging intervals for input variables. For each variable and each averaging period between 1 and 97 h, a separate model was built. By inspecting values of the coefficient of correlation between measured and modelled concentrations, optimal averaging periods for each variable were selected. A new dataset for building the forecasting model was then calculated as temporal moving averages (running means) of former variables. A multi-layer perceptron type of neural networks is used as the forecasting model. Index of agreement, calculated for the entire dataset including the data for model building, ranged from 0.91 to 0.97 for the respective pollutants. As suggested by the analysis of the relative importance of the input variables, different agreements for different pollutants are likely due to different sources and production mechanisms of investigated pollutants. A comparison of the new method with more traditional method, which takes hourly averages of the forecast hour as input variables, showed similar or better performance. The model was developed for the purpose of public-health-oriented air quality forecasting, aiming to use a numerical weather forecast model for the prediction of the part of input data yet unknown at the forecasting time. It is to expect that longer term averages used as inputs in the proposed method will contribute to smaller input errors and the greater accuracy of the model.     

高原环境对直升机旋翼性能的影响分析

针对高原环境直升机旋翼性能的估算,建立了一个基于自由涡理论的旋翼尾迹模型,并推导了旋翼拉力和功率的计算方法。以UH-60黑鹰直升机为算例,分别计算了其在海平面及高原环境的旋翼性能,探讨了海拔高度对直升机旋翼性能的影响规律。计算结果表明,高原环境的气候条件对直升机旋翼性能有显著影响,旋翼拉力较海平面环境减小约30%。     

峨眉河乐山市中区段水环境污染及防治对策

为了确保峨眉河乐山市中区段水环境质量满足社会经济的发展，在全面调查峨眉河流域污染现状的基础上，对该流域水环境进行系统的分析和评价，得出乐山市中区段水环境质量达到国家《地表水环境质量标准》（GB3838—2002）中Ⅱ类水质标准，流域的主要污染为城镇生活污染源。同时，计算出峨眉河的水环境容量，提出对污染源施行总量控制方案。并根据峨眉河流域污染源的实际情况，针对城镇生活污染源、工业污染源和面源的不同特点提出具体的防治对策。     

Hg concentrations and related risk assessment in coral reef crustaceans, molluscs and fish from New Caledonia

There is a dramatic lack of data on Hg levels in marine organisms from tropical areas, and in particular from New Caledonia. For the first time, this study reports the total Hg concentrations in the tissues of several marine taxa from the New Caledonian lagoon. Seafood from both wild and farmed populations was considered. Hg concentrations varied over three orders of magnitudes according to factors including species, age (size/weight), trophic level, lifestyle and geographical origin. Taking into account the edible tissues, estimations of the amount of flesh that should be consumed by a 60-kg person to reach the Hg Provisional Tolerable Weekly Intake (PTWI) reveal acceptable risk for Human health in general. However, a risk was clearly identified in one site of the lagoon (i.e. Grande Rade) where high Hg concentrations were measured. These concentrations were higher than values reported in the current literature.     

地下水位下降对塔里木河下游绿洲生态环境的影响——以34团为例

塔里木河地处我国西北干旱区，是我国最长的内陆河。过去50a来由于大规模的不合理的水土资源开发和人类活动，导致塔里木河在以水资源开发利用为核心的大强度人类经济、社会活动的作用下，流域自然生态过程发生了显著变化。分析了塔里木河下游地下水位下降对绿洲农业生态环境的影响，提出了保障该地区生态和经济发展的对策与建议。     

论焦化行业环境风险防范措施及应急预案

本文对焦化行业的原辅材料及产品的理化性质、生产过程中潜在的环境风险进行了识别，并在此基础上有针对性的提出了焦化行业环境风险防范措施及应急预案。     

生态岛建设过程中环境类指标构建研究——以崇明岛为例

提出了将压力 状态 响应（PSR）模型与系统分析法理论集成起来构建生态岛建设过程中环境类指标的方法和步骤。指标构建过程分为4个步骤：（1）首先利用已有生态区域（岛）相关环境类指标确定备选指标集；（2）利用PSR模型对指标逻辑关系进行分析筛选；（3）以2010年为近期目标年，利用系统分析法确定指标核心要素，得到二次筛选指标；（4）以2030年为远期目标年，以综合性和动态性为依据确定最终指标。以上海市崇明岛为例，确定水、气、土为核心考核要素，构建了基于崇明生态岛建设过程的近期及远期目标的环境类考核指标体系。指标评价结果表明，崇明生态岛建设过程中环境类综合指数为72，其中环境压力指数、环境质量指数、环境保护指数分别为85、80和51，与崇明岛实际较为吻合。部分研究结果已在崇明岛生态建设过程中得到实际应用。     

Perspectives on utilising Community Land Trusts as a vehicle for affordable housing provision

With lack of affordable housing being clearly identified as a social and economic exclusion issue for most communities, innovative ways of addressing this deficiency should be considered. Increasingly local communities are engaging with the possibility of direct provision themselves and discussion around this notion has profound implications for community cohesion. One community-based solution gaining popular support within communities, and with government ministers, is the Community Land Trust mechanism. This involves control and ownership of land to help ensure affordable housing is built and remains affordable in perpetuity for the community. The language and difficulties with definition of terms, together with the complexity of engaging relevant stakeholders in a changing policy and legislative framework can be problematic. This may lead to apparent lack of consensus within communities on the way forward. Perceptions of local housing issues and ways to address them are sometimes vague, sometimes diverse but rarely apathetic. This paper includes data from two case studies in North East England, which are examined using interviews with key players, as a means of seeking some practical solutions.     

江苏省能源可持续发展模式初探

针对目前江苏省能源可持续发展面临的挑战，以保障江苏能源综合供需平衡和实现能源 经济 环境协调发展为目标，以调整能源结构、优化能源供给体系、提高能源转化效率和清洁性为立足点，以充分利用省内不同区位的能源发展优势为主线，因地制宜地提炼出江苏省能源可持续发展的基本模式，包括自有资源优化开发模式和外部资源导入开发模式两大类型。其中，自有资源优化开发模式又可分为徐州煤炭工业综合体、苏北石油工业基地和沿海滩涂型可再生能源基地3种子模式；外部资源导入开发模式可分为沿江电力生产基地、苏南电力负荷中心和沿海临港型能源基地3种子模式。各种模式协同发展，有利于增强江苏省的能源可持续发展能力.     

金海水库夏季浮游植物群落结构与水质调查

2012年夏季对金海水库水体物理和化学指标和浮游植物的群落结构组成进行了调查。结果表明，水库整体水质状态较为良好,金海水库夏季综合营养状态指数为42.34，水库水体在一定程度上已经呈现中营养水平向轻度富营养化转化的趋势。通过夏季对金海水库浮游植物的调查，共检出浮游植物27种，其中绿藻门14种，硅藻门7种，甲藻门2种，蓝藻门2种，裸藻门2种。优势种属为绿藻门和硅藻门，其中绿藻门的种类和数量均居于首位。