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A preliminary study on pollution characteristics of surfactant substances in fine particles in the Beibu Gulf Region of China

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Journal of Environmental Sciences 2021年第4期33卷 363-372页

作者： Zhengzheng Zhang Hong Li Hongyan Liu Yingchen Bai Jinjuan Li Guorui Zhi Yanting Yu Wenjun Li Hao Zhang Fan meng National Center for Quality Supervision and Test of Building engineering China Academy of Building ResearchBeijing 100013China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100021China college of Resource and Environmental engineering Guizhou UniversityGuiyang 550025China Puyang Institute of Environmental Protection Science Puyang 457000China college of geoscience and surveying engineering Chinese University of Mining&TechnologyBeijing 100083China School of Science Chinese University of GeosciencesBeijing 100083China

The pollution characteristics of surfactant substances in fine particles(PM_(2.5))in spring were studied in the Beibu Gulf Region of China,68 samples of PM_(2.5)were collected at Weizhou Island in Beihai City from March 12 to April 17,*** Anionic Surfactant Substances(ASS)and Cationic Surfactant Substances(CSS)in the samples were analyzed using Byethyl Violet Spectrophotometry and Disulfide Blue Spectrophotometry,*** with the data from backward trajectory simulation,the effects of air pollutants from remote transport on the pollution characteristics of surfactant substances in PM_(2.5)in the Beibu Gulf Region were analyzed and *** results showed that the daily mean concentrations of ASS and CSS in spring in the Beibu Gulf Region were 165.20 pmol/m^(3)and 8.05 pmol/m^(3),and the variation ranges were 23.21–452.55 pmol/m^(3)and 0.65–31.31 pmol/m^(3),accounting for 1.82‰±1.65‰and 0.12‰±0.11‰of the mass concentration of PM_(2.5),*** concentrations were lower than those in comparable regions around the *** was no clear correlation between the concentrations of ASS and CSS in PM_(2.5)and the mass concentrations of PM_(2.5).Tourism and air transport had a positive contribution on the concentrations of *** concentration of surfactant substances in PM_(2.5)was significantly impacted by wind speed and wind *** temperature,air pressure and precipitation had little effect on the concentrations of surfactant *** substances in PM_(2.5)significantly impacted *** also showed that the main sources of surfactant substances were from the southern China and Southeast Asia.

关键词： Fine particles Surfactant substances Pollution characteristics Impact factors Beibu gulf region of China

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Assessment of tomographic window and sampling rate efects on GNSS water vapor tomography

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Satellite Navigation 2023年第1期4卷 155-166,I0005页

作者： Fei Yang Yilin Sun Xiaolin meng Jiming Guo Xu Gong college of geoscience and surveying engineering China University of Mining and Technology-BeijingBeijing 100083China college of Architecture and Civil engineering Beijing University of TechnologyBeijing 100124China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The ground-based Global Navigation Satellite System(GNSS)water vapor tomography is increasingly important in GNSS *** the multi-GNSS and more ground-based GNSS sites can be incorporated into the regional water vapor tomographic model,determining the tomographic window and sampling rate is crucial for the modelling of the water vapor *** two factors afect not only the number of available signal rays from the satellites,but also the number of tomographic voxels crossed by the signal *** study uses Hong Kong as the research area to explore the impact of 12 schemes with diferent tomographic window and sampling rate on the three water vapor tomography methods,including Least squares,Kalman fltering,and Multiplicative Algebraic Reconstruction Technique(MART).Numerical results show that the tomographic results with the three methods get better as the width of the tomographic window decreases and the sampling rate increases in these 12 schemes,and it is found that the Least squares method is most afected by the two factors,followed by Kalman fltering and MART *** is recommended to set a tomographic window width of 10 min and a sampling rate of 300 s in a GNSS water vapor tomographic experiment with dense GNSS site like Hong Kong.

关键词： GNSS meteorology Water vapor Tomography

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毛乌素沙漠植被的神经网络提取方法研究

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计算机与数字工程 2024年第1期52卷 206-212页

作者：孟健熊文豪周寒张晓倩刘天琦高贤君中国矿业大学(北京)地球科学与测绘工程学院北京100083 长江大学地球科学学院武汉430100 内蒙古自治区测绘地理信息中心呼和浩特010050 新疆大学地质与矿业工程学院乌鲁木齐830047

地表植被作为人类自然生态系统的一个重要组成部分,在减轻土壤侵蚀、维持生态平衡、提高防风固沙能力,以及维持局部区域经济可持续发展等许多方面都发挥着重要的主导作用。近年来,卫星遥感技术凭借其大范围、多尺度、多时相的优势,已经... 详细信息

地表植被作为人类自然生态系统的一个重要组成部分,在减轻土壤侵蚀、维持生态平衡、提高防风固沙能力,以及维持局部区域经济可持续发展等许多方面都发挥着重要的主导作用。近年来,卫星遥感技术凭借其大范围、多尺度、多时相的优势,已经成为一种低成本、高效率的植被覆盖估计算法,在植被提取和变化监测中表现出了重要的应用价值。论文以榆林市毛乌素沙漠地区为主要研究区域,利用手机可视化虚拟图像处理环境(Environment for Visualizing Images,ENVI)分析软件对landsat8遥感影像进行地表植被的信息提取,采用不同的监督分类方法对植被信息进行分类提取,并对不同的监督分类结果进行质量精度分析评定。结果表明,神经网络方法较其他方法在沙漠植被提取方面表现出较优的性能,可以实现对沙漠植被的动态变化监测。

关键词：毛乌素沙漠植被提取神经网络精度评定

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Geostatistical Analysis of Soil Nutrients Based on GIS and Geostatistics in the Typical Plain and Hilly-Ground Area of Zhongxiang, Hubei Province

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Open Journal of Soil Science 2013年第5期3卷 218-224页

作者： Yangbo Xu Donglin Dong Guobin duan Xuetao Yu Zhiwei Yu Wei Huang college of geoscience and surveying engineering China University of Mining & Technology Beijing China college of Resources and Environment Huazhong Agricultural University Wuhan China. State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China college of geoscience and surveying engineering China University of Mining & Technology Beijing China State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China college of geoscience and surveying engineering China University of Mining & Technology Beijing China

Techniques of geostatistics are used to perform traditional statistical analysis and spatial structural analysis with ArcGIS, geostatistical software GS+ and statistical software SPSS in order to obtain the knowledge of characteristics of distribution and spatial variability of soil nutrients in different parts of Zhongxiang, Hubei Province. Some skewed values appeared during the analyses. To decrease the influence of those skewed values, domain processing and Box-Cox transformation were used. The results indicated spatial variability of Total N, Avail. P, rapidly-available potassium (R-Avail. K) and effective zinc (Effect. Zn) was strong, that of organic carbon (Org. C), effective molybdenum (Effect. Mo) and effective copper (Effect. Cu) was medium while that of others was weak. Fitted model of Total N, R-Avail. K and Effect. Mo was spherical model, that of Org. C and Effect. Zn was exponential model, while fitted model of Avail. P and Effect. Cu was Gaussian model. Ratio of variability caused by random factors to overall variability was large. What’s more, the ranges of spatial autocorrelation of soil nutrients had much difference. The smallest value was 3600 m in Effect. Zn while the largest was 77970 m in Org. C. Other characteristics were also included. The study is helpful to soil sampling design, to make people realize the influence of Han River to spatial variability of soil nutrients in this area, and to spatial interpolation and mapping.

关键词： Zhongxiang Soil Nutrients Geostatistical Analysis Geostatistics GIS GS+ SPSS

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基于信息熵的GlobeLand 30和WorldCover耕地破碎区一致性分析

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地球信息科学学报 2023年第5期25卷 1027-1036页

作者：段艳慧赵学胜彭舒中国矿业大学(北京)地球科学与测绘工程学院北京100083 国家基础地理信息中心北京100830

在山地丘陵等地物破碎度较高的地区,分辨率大小对地表覆盖产品质量的影响更大。为此,本文以GlobeLand 30和WorldCover产品的耕地为例,引入信息熵对多源地表覆盖产品进行了一致性分析。首先,计算研究区耕地对应原始影像不同波段的信息熵... 详细信息

在山地丘陵等地物破碎度较高的地区,分辨率大小对地表覆盖产品质量的影响更大。为此,本文以GlobeLand 30和WorldCover产品的耕地为例,引入信息熵对多源地表覆盖产品进行了一致性分析。首先,计算研究区耕地对应原始影像不同波段的信息熵,以反映单一耕地类的总体不确定性;其次,为了描述影像局部区域的不确定性分布,构建局部信息熵;最后,对两产品的不确定性分级叠加,进行一致性分析。结果表明:(1)信息熵可以在产品空间分布的基础上更加细致的反映耕地内部的不确定性变化情况,直观的看出难以判定类别的区域分布;(2)30 m分辨率的GlobeLand 30产品耕地总体不确定性大于10 m分辨率的WorldCover产品。从不确定性分布情况来看,两产品不确定性较大的地区主要围绕耕地与其他地物的交错地区,其混合像元更多,地物类别模糊,不确定性更大;(3)对于两产品不确定性的叠加结果,分辨率差异带来的耕地不确定性差异分别为蓝波段34.54%、绿波段51.13%、红波段46.03%、近红外波段61.48%;(4)对于两产品空间分布不一致的地区,GlobeLand 30产品的不确定性也更大,即受到分辨率的影响较大。

关键词：地表覆盖信息熵一致性分析耕地不确定性 GlobeLand30 WorldCover Landsat 8 Sentinel-2

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Porosity Calculation of Tight Sand Gas Reservoirs with GA-CM Hybrid Optimization Log Interpretation Method

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Journal of geoscience and Environment Protection 2014年第3期2卷 92-98页

作者： Ya-Nan duan Bao-Zhi Pan Xue Han Hai-Tao Zhang Xiao-Ming Yang college of Earth Exploration Science and Technology Jilin University Changchun China Exploration and Development Institute of Changqing Oilfield PetroChina Xi’an China Shengli Petroleum engineering Co. Ltd. the First Branch of the Logging Company Dongying China

Tight sand gas reservoirs are our country’s fairly rich unconventional natural gas resources, and their exploration and development is of prime importance. Sulige Gas Field which located in the northern Ordos Basin is tight sand gas reservoirs. It is typically featured by low porosity and low permeability, and the error of porosity calculation by traditional methods is larger. Multicomponent explanation model is built by analyzing the thin slice data, and the objective function is got according to the concept of optimization log interpretation method. This paper puts the Genetic Algorithm and the Complex Algorithm together to form the GA-CM Hybrid Algorithm for searching the optimal solution of the objective function, getting the porosity of tight sandstone gas reservoirs. The deviation got by this method is lesser compared with the core porosity, with a high reliability.

关键词： Porosity Tight Sand Gas Reservoirs Low Porosity and Low Permeability GA-CM Optimization Multicomponent Explanation Model

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The Spatial Distribution Pattern Analysis of City Infrastructure Cases of Urban Management

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Journal of geoscience and Environment Protection 2018年第12期6卷 21-42页

作者： Jiwei Hou Jianhua Liu Siyu Li Shiran Song Congcong Li Yueming duan Baoshan Zeng Key Laboratory for Urban Geomatics of National Administration of surveying Mapping and Geoinformation Beijing China School of Geomatics and Urban Spatial Information Beijing University of Civil Engineering and Architecture Beijing China

The effective disposal of daily city infrastructure cases is an important issue for urban management. To more effectively utilize a large amount of historical cases data collected and accumulated in the urban grid management system, and to analyze their spatial distribution pattern information for city managers, this study used the comparative kernel density analysis method in two types of cases (i.e. power facilities and traffic guardrail) in Xicheng District, Beijing for the year 2016 and 2017. This research analyzes them at different scales (300 m, 600 m, 1,200 m), and the experiment results show that the method of comparative kernel density analysis is able to provide an intuitively spatial visualization distribution analysis of city infrastructure related cases. The quantitative information of spatial agglomeration degree is helpful for city managers making decision.

关键词： City Management Cases Spatial Distribution Analysis Distribution Scale Hotspot Distribution

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多功能视角下县域乡村发展水平评价与类型划分研究

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江西农业大学学报 2020年第4期42卷 829-838页

作者：田超程琳琳殷婷婷中国矿业大学(北京)地球科学与测绘工程学院北京100083

【目的】开展乡村发展水平评价和类型划分的综合研究,对厘清乡村发展的内部差异和主导因素,助力乡村振兴具有重要意义。【方法】以北京市门头沟区为研究区域,选择多功能视角下生产、生活和生态功能在内的19个指标,通过综合评价法对各乡... 详细信息

【目的】开展乡村发展水平评价和类型划分的综合研究,对厘清乡村发展的内部差异和主导因素,助力乡村振兴具有重要意义。【方法】以北京市门头沟区为研究区域,选择多功能视角下生产、生活和生态功能在内的19个指标,通过综合评价法对各乡村三生功能、发展水平及类型划分进行研究,进而根据各县域乡村主导功能类型的识别结果,探索各乡村差异化发展的有效路径。【结果】各乡村发展水平差异相对较大,存在显著的空间分异特征,空间分布呈现东西部发展水平较高,中部相对较低的态势。三生功能指数的变化与其生产、生活、生态条件密切相关。根据主导功能的识别结果,将研究区划分为生产建设区、生活保障区、生态保育区和综合发展区,其中,生态保育区和综合发展区所占比例最大,为33.30%,生产建设区所占比例最小,仅为11.10%。【结论】研究结果可为明确乡村功能定位,探究区域内部发展差异,优化主导功能区划,促进乡村可持续发展和乡村振兴提供科学依据。

关键词：多功能县域乡村发展水平类型划分主导功能

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Analysis of Geographical Distribution of Missing Children Based on the Missing Children Mobile GIS Mutual Assistance System of China

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Journal of geoscience and Environment Protection 2017年第12期5卷 117-134页

作者： Xiaodong Gong Hao Cheng Lu Yang Yueming duan Yuan Yao Yafei Feng Le Fu Jianhua Liu Mingyi Du Key Laboratory for Urban Geomatics of National Administration of surveying Mapping and Geoinformation Beijing China college of surveying and Mapping engineering Beijing University of Civil Engineering and Architecture Beijing China

The Missing Children Mobile GIS Mutual Assistance System of China (MCMAS) is a mobile service software based on mobile GIS platform software, and it is committed to providing the most convenient and efficient system of personally mutual tracing services for missing children family and society. Relying on collaborative utilization of location-based service technology, face image intelligent recognition technology, cloud computing technology, public big data sharing technology, and mobile GIS technology, the MCMAS has achieved prominent application effects since it was deployed. At present, the MCMAS is running soundly, and it has received and released the information about 1011 missing children from May 25, 2016 to May 25, 2017. In order to explore the geographical distribution features and the influencing factors of missing children, the data of missing children are used for spatial and visual analysis by the data mining and GIS technologies. At the same time, we have built the spatial thermodynamic diagram of the big data of China missing children. By comparing provinces and cities with a higher proportion of missing children, the results showed that: 1) The high proportion of missing children spatially concentrated in the eastern part of the China. 2) The number of missing children was significantly correlated with the population density and economic status of the city. Furthermore, the paper macro-levelly presents a basic basis for rescuing the missing children from two aspects: regionally spatial characteristics and influencing factors.

关键词： Missing Children Mobile GIS Location Based Service Spatiotemporal Big Data Mining

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基于循环神经网络的煤层气井产气量预测方法研究

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煤炭科学技术 2021年第9期49卷 176-183页

作者：董维强孟召平沈振宗志敏陈涛中国矿业大学(北京)地球科学与测绘工程学院北京100083

煤层气井产气量是衡量一口煤层气井产气能力和工程开发效果的重要指标,准确预测日产气量是保证煤层气高效生产的一个关键问题。以沁水盆地南部郑庄区块3号煤层为研究对象,选取煤层气井排采动态参数,如井底流压、液柱高度、套压、日产水... 详细信息

煤层气井产气量是衡量一口煤层气井产气能力和工程开发效果的重要指标,准确预测日产气量是保证煤层气高效生产的一个关键问题。以沁水盆地南部郑庄区块3号煤层为研究对象,选取煤层气井排采动态参数,如井底流压、液柱高度、套压、日产水量和冲次作为自变量,分析了日产气量与这些排采参数之间的相关性,建立了基于循环神经网络的煤层气井产气量预测模型与方法。研究结果表明,煤层气井日产气量与冲次呈正相关性,日产气量与井底流压、套压、液柱高度和日产水量呈负相关性。基于深度学习随机森林算法中的特征重要性分析,研究了排采动态参数与日产气量之间的非线性关系以及预测模型中对日产气量的贡献率,得到了排采参数对日产气量影响的重要性排序表现为:井底流压>液柱高度>套压>日产水量>冲次。在此基础上,基于循环神经网络改进的长短时记忆神经网络预测模型,将Z4-026井排采数据代入模型计算,预测了煤层气井未来60 d产气量情况,并将预测结果与传统的支持向量机回归模型、随机森林回归模型以及BP神经网络模型对比,发现改进的长短时记忆神经网络预测模型,拟合效果相对较好,实际日产气量与预测日产气量之间的误差小于5%。在郑庄区块5口煤层气井的产气量预测分析中,相对误差小于10%。因此该方法将为煤层气井产气量预测和制定合理的排采制度提供了有效途径。

关键词：煤层气井产气量预测排采参数循环神经网络

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