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1.
利用历史监测数据建立河流水质数学模型的研究   总被引:3,自引:0,他引:3  
利用河流历史监测数据,采用一维河流输入输出线性水质模型建立了河流水质控制数学模型,证明了河流各水质监测断面水质间的线性关系,推导出了用历史数据估算模型参数的计算公式,以泾河甘肃段为例,介绍了建模过程,采用该方法建立的水质数学模型符合实际,精度高,能满足水质管理的要求。  相似文献   

2.
常用的“实测法”有“历史数据估算法”和“网格法”两种。对于中等城市,往往因常规监测点位少而应用“历史数据估算法”难以满足要求;“网格法”则因其布点多、周期长(一般需进行采暖期和非采暖期的布点监测),投入的人力、物力大而使中等城市的三级站难以胜任。我们采用适量网格布点一次性监测和历史数据相结合的方法,使之相互印证,互补长短。并以确定特征点位突出优化点位的代表性,以严密的统计分析和检验保证优化点位的准确性。  相似文献   

3.
环境背景值反映了环境质量的原始状态,是确定区域环境污染程度的基础,在环境质量评价、政府决策中起着十分重要的作用。对于具有矿产背景的区域,由于其水文地质环境复杂,传统背景值的计算方法存在局限性。笔者以明白河流域为研究对象,利用水文分析工具,结合实际采样检测,将流域内氟化物的来源分为4类,单独进行估算,并利用研究区出境断面处的多年历史数据对估算结果进行验证,预测精度达到89.4%;最后只考虑自然因素对总量的贡献,计算出河流中氟化物的背景值为1.72 mg/L。  相似文献   

4.
以北京市某典型区域作为研究对象,在收集大量相关资料与实测历史噪声数据的基础上,对研究区域内的声环境质量影响因素进行灰色关联度分析,并运用灰色理论建立GM(1,1)模型进行预测。结果表明,影响城市区域声环境质量因素从大到小的排序依次为:机动车辆﹥常住人口数量﹥平均车流量﹥地区生产总值﹥城市道路桥梁﹥基础设施投资﹥治理噪声环保投资;以研究区域内噪声污染实测历史数据建立的GM(1,1)模型精度符合要求标准,根据GM(1,1)模型预测北京市“十二五”期间声环境质量达标且有轻微下降趋势。  相似文献   

5.
基于调查监测数据和历史数据,分析兴凯湖中国区域水质及污染现状。结果表明,兴凯湖为Ⅳ类水质,水质状况为轻度污染,处于轻度富营养化状态。主要污染指标为总磷,浓度呈逐年升高的趋势。分析其原因,穆棱河分洪水是兴凯湖地面水的主要来源,这部分水质远较其他入湖河流水质差,因此穆棱河湖北闸在洪水期的泄洪水是兴凯湖的一个主要污染源。  相似文献   

6.
以广东省珠海市2018年完工的唐家湾沙滩为研究对象,基于OpenGeoSys程序构建海水入侵数值模型,根据水文地质调查数据,建立沙滩修复前地下水运动的数学模型,利用地下水盐度历史数据进行参数率定与模型验证。在该模型基础上,根据填沙的水文地质参数,改变模型相应部分的属性,分析针对不同人工沙滩修复方案情景下的咸淡水界面运移规律。结果表明:人工填沙可加速海水入侵,填沙厚度对海水入侵程度影响较小;增加填沙宽度可以有效缓解海水入侵,当填沙宽度达到50 m时,可驱退咸淡水界面至沙滩修复前的状态。  相似文献   

7.
大数据解析技术在大气环境监测中的应用研究   总被引:3,自引:1,他引:2  
针对近年来新兴的大数据及挖掘、分析技术,对大数据解析技术在环境科学研究中的应用进行了分析和探析。以城市局部地区大气细颗粒污染物PM2.5浓度计算为例,筛选了PM2.5浓度历史数据、气象条件、交通状况、人群活动情况、网格道路状况等数据为影响特征量,分析了用神经网络法进行大数据解析和推演的原理和数学过程,是用数学、计算机、统计等方法研究解决多元、非线性复杂环境问题的一种新的探索。  相似文献   

8.
对建设项目环境影响现状监测历史数据的所有权归属进行了分析,环境监测机构具有现状监测成果的所有权,委托方有使用权.应对环境现状监测数据进行知识产权保护,使监测数据得到更好利用.  相似文献   

9.
在全省城市环境空气质量监测网优化并运行六年的基础上 ,采用历史数据计算法对河南省环境空气质量监测网进行了优化。通过优化方法和监测项目的探索 ,确定了省控站数目 ,特别是提出了系统、完整的优化指标 ,优化结果是令人满意的。  相似文献   

10.
介绍了金山区PM2.5监测概况,并采用2012年环保部颁发的新标准对该区所监测的PM2.5数据进行评价,通过与上海市数据比较,与周围区县比较以及各点位历史数据比较等多方面对该区历史数据进行了分析,结合上述分析讨论了该区PM2.5的主要来源  相似文献   

11.
Most of the existing plotting position formulas have been proposed for use in the analysis of systematic flood records, but little has been reported on the plotting formulas for historical or non-systematic flood samples. In particular, no previous investigations have specifically examined the probability plots for the Pearson type III (P3) distribution in the analysis of historical flood information. The present paper suggests a new plotting position formula for the P3 distribution for use with both systematic and historical flood records. The proposed formula has a simple structure as do most existing formulas, but it is more flexible because in can take explicitly into account the skewness coefficient of the underlying distribution. Further, results of graphical and numerical comparisons have demonstrated that the suggested formula provided the least bias in flood quantile estimation as compared with many available plotting formulas, including the well-known Weibull formula. Finally, results of a numerical example using actual flood data have indicated the practica convenience of the proposed plotting formula. It can be concluded that the formula developed in this study is the most appropriate for the P3 distribution in the analysis of flood records considering historical information.  相似文献   

12.
Nitrate contamination of water sources is a concern where large amounts of nitrogen fertilizers are regularly applied to soils. Ingested nitrate from dietary sources and drinking water can be converted to nitrite and ultimately to N-nitroso compounds, many of which are known carcinogens. Epidemiologic studies of drinking water nitrate and cancer report mixed findings; a criticism is the use of nitrate concentrations from retrospective drinking water data to assign exposure levels. Residential point-of-use nitrate data are scarce; gaps in historical data for municipal supply finished water hamper exposure classification efforts. We used generalized linear regression models to estimate and compare historical raw water and finished water nitrate levels (1960s--1990s) in single source Iowa municipal supplies to determine whether raw water monitoring data could supplement finished water data to improve exposure assessment. Comparison of raw water and finished water samples (same sampling date) showed a significant difference in nitrate levels in municipalities using rivers; municipalities using other surface water or alluvial groundwater had no difference in nitrate levels. A regional aggregation of alluvial groundwater municipalities was constructed based on results from a previous study showing regional differences in nitrate contamination of private wells; results from this analysis were mixed, dependent upon region and decade. These analyses demonstrate using historical raw water nitrate monitoring data to supplement finished water data for exposure assessment is appropriate for individual Iowa municipal supplies using alluvial groundwater, lakes or reservoirs. Using alluvial raw water data on a regional basis is dependent on region and decade.  相似文献   

13.
Compliance with criteria limiting the discharge of pollutants or standards of water quality in the reveiving water body are assessed by monitoring. In order to set limits or standards, the features of the discharge or the water body to be monitored must be characterized. This generally involves the fitting of a probability distribution to historical data or data from preliminary sampling and the choice of a statistic for the limit or standard. Monitoring data collected to assess compliance are assumed to follow data will help to ensure that the assumption is met. Statistical methods which either assume a distribution for the quality variable or involve a transformation to a binary variable are compared. The validity of the underlying assumptions in the application of the methods to water or effluent quality data is discussed.  相似文献   

14.
The quality of human life has been increasingly a significant concern, where the public space environment is one of the critical influential factors. The location with historic buildings has been an attractive destination for people to enjoy outdoor activities. Moreover, the building façade, being the boundary element of the public space, plays an important role in deciding human outdoor activities. Whilst many studies focus on building materials, structure, energy consumption and human attitude towards building façade in public spaces, limited studies have been conducted to analyse the influence of the small-scale public space historic building facade on human outdoor activities. Therefore, this study aims to explore whether the façade of historical buildings in small-scale public spaces causes people to aggregate. This study was conducted in the Donglu campus of Yunnan University, Kunming, China. A comprehensive analysis of façade characteristics (e.g. age, structure, materials) of historical buildings, combined with the questionnaire survey data of facade preference of buildings was conducted in this campus in May 6–12, 2019. The method of spatial statistical analysis was adopted to analyse the relationship between historical building façade and human behaviour. The results show that human preference exhibited an aggregation phenomenon, demonstrating that the human behaviour could be influenced by the façade characteristics of historical buildings. The peculiar building façade (e.g. Huize Hall, Zhigong Hall) could attract more human attention, in which architectural style and decoration played a vital role. Nevertheless, the historic building's long history and cultural inherence also affected human preferences. Such results help to improve the protection and use of historical buildings in public spaces, enhance the understanding of impacts about historical buildings on human behaviour, and provide a reference for new building façade design with the consideration of human outdoor activities.  相似文献   

15.
Terrestrial laser scanning is a popular methodology that is used frequently in the process of documenting historical buildings and cultural heritage. The historical peninsula region sprawls over an area of approximately 1,500 ha and is one of the main aggregate areas of the historical buildings in Istanbul. In this study, terrestrial laser scanning and close range photogrammetry techniques are integrated into each other to create a 3D city model of this part of Istanbul, including some of the buildings that represent the most brilliant areas of Byzantine and Ottoman Empires. Several terrestrial laser scanners with their different specifications were used to solve various geometric scanning problems for distinct areas of the subject city. Photogrammetric method was used for the documentation of the facades of these historical buildings for architectural purposes. This study differentiates itself from the similar ones by its application process that focuses on the geometry, the building texture, and density of the study area. Nowadays, the largest-scale studies among 3D modeling studies, in terms of the methodology of measurement, are urban modeling studies. Because of this large scale, the application of 3D urban modeling studies is executed in a gradual way. In this study, a modeling method based on the facades of the streets was used. In addition, the complimentary elements for the process of modeling were combined in several ways. A street model was presented as a sample, as being the subject of the applied study. In our application of 3D modeling, the modeling based on close range photogrammetry and the data of combined calibration with the data of terrestrial laser scanner were used in a compatible way. The final work was formed with the pedestal data for 3D visualization.  相似文献   

16.
选择出11项评价因子,采用单项分指数法和平均分指数法,在涨潮、落潮、涨落潮时分别对伶仃洋东部海域水质进行监测,并与历史资料进行对比,对评价因子超标进行评价和原因分析,提出了补救与预防措施.  相似文献   

17.
道路交通噪声自动监测应用探讨   总被引:3,自引:0,他引:3  
结合城市道路路网状况及实际噪声监测数据和历史实验数据,对道路交通噪声自动监测数据的有效性、监测点位布设进行了研究,对道路交通噪声监测点位优化提出建议。  相似文献   

18.
PCBs have been banned since the late 1970s, but concentrations still exist in sediments and riverine fish and continue to exceed regulatory limits which can result in negative health effects. This study looks at historical records of PCB and Arochlor concentrations in surface water, sediments, and fish tissue for the Lower Leon Creek, Bexar County in Texas. Temporal analysis on the concentrations of PCBs and Arochlors was conducted for detection and exceedance of selected screening criteria. In addition, the half-lives of select PCB congeners were calculated for 2007–2012 data to ascertain differences in PCB concentrations with their hydrophobicity. Source analysis was conducted to determine the potential contributing sources of PCB contamination using source data (landfills, outfalls, etc.) and the PCB exceedance data. For sediment and fish tissue sampling results, historic data shows high concentrations of PCB/Arochlors over the course of several decades. The historical data is characterized as being widely variable for detections in Arochlors and concentrations between years, with a dramatic drop in concentrations detected starting in 2009. Overall, the sampling locations adjacent to and downstream from the former Kelly Air Force Base have the highest concentrations of PCB/Arochlors over the longest period of time. The results of this work will aid regulatory agencies in addressing impairment.  相似文献   

19.
太原地区大气污染物输送特征分析   总被引:8,自引:1,他引:7  
使用太原地区历史气候资料讨论了太原市大气污染物向外输送的规律.通过对飞机航测、地面监测和低空同步气象观测资料的综合研究,对太原市大气污染物向太原盆地中、南部的输送通道和SO2向气溶胶转化等方面提出了进一步的认识.  相似文献   

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