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Multiple linear regression models of urban runoff pollutant load and event mean concentration considering rainfall variables 被引量:28
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作者 Marla C.Maniquiz Soyoung Lee Lee-Hyung Kim 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第6期946-952,共7页
Rainfall is an important factor in estimating the event mean concentration (EMC) which is used to quantify the washed-off pollutant concentrations from non-point sources (NPSs). Pollutant loads could also be calcu... Rainfall is an important factor in estimating the event mean concentration (EMC) which is used to quantify the washed-off pollutant concentrations from non-point sources (NPSs). Pollutant loads could also be calculated using rainfall, catchment area and runoff coefficient. In this study, runoff quantity and quality data gathered from a 28-month monitoring conducted on the road and parking lot sites in Korea were evaluated using multiple linear regression (MLR) to develop equations for estimating pollutant loads and EMCs as a function of rainfall variables. The results revealed that total event rainfall and average rainfall intensity are possible predictors of pollutant loads. Overall, the models are indicators of the high uncertainties of NPSs; perhaps estimation of EMCs and loads could be accurately obtained by means of water quality sampling or a long term monitoring is needed to gather more data that can be used for the development of estimation models. 展开更多
关键词 event mean concentration (EMC) multiple linear regression model LOAD non-point sources RAINFALL urban runoff
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Influencing Factors of Museum Self-Improvement in China: A Multiple Linear Regression Analysis
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作者 Zhenjing Gu Da Meng +1 位作者 Hui Yang Xiaofei Liu 《Proceedings of Business and Economic Studies》 2024年第6期238-250,共13页
The purpose of this research is to explore the factors influencing the self-improvement process of museums in China and to conduct empirical analyses based on multiple linear regression models.As core institutions for... The purpose of this research is to explore the factors influencing the self-improvement process of museums in China and to conduct empirical analyses based on multiple linear regression models.As core institutions for inheriting and displaying cultural heritage and enhancing public cultural literacy,museums’self-improvement is of great significance in promoting cultural development,optimizing the supply of public cultural services,and enhancing social influence.This paper constructs a multiple linear regression model for the influencing factors of museum self-improvement by integrating several key variables,including emerging cultural and museum business(EF),institutional reform(SR),research and innovation level(RIL),management level(ML),and the museum cultural and creative industry(MCCI).The study employs scientific methods such as literature review,data collection,and data analysis to thoroughly explore the internal logic of museum operations and development.Through multiple linear regression analyses,it quantifies the specific influence and relative importance of each factor on the level of museum self-improvement.The results indicate that the management level(ML)is the dominant factor among the variables studied,exerting the most significant influence on museum self-improvement.Based on these empirical findings,this paper provides an in-depth analysis of the specific factors affecting museum self-improvement in China,offering solid theoretical support and practical guidance for the sustainable development of museums. 展开更多
关键词 Museum self-improvement Influencing factors multiple linear regression model
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Combined model based on optimized multi-variable grey model and multiple linear regression 被引量:12
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作者 Pingping Xiong Yaoguo Dang +1 位作者 Xianghua wu Xuemei Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期615-620,共6页
The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to elimin... The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to eliminate the random fluctuations or errors of the observational data of all variables, and the combined prediction model together with the multiple linear regression is established in order to improve the simulation and prediction accuracy of the combined model. Finally, a combined model of the MGM(1,2) with optimized background value and the binary linear regression is constructed by an example. The results show that the model has good effects for simulation and prediction. 展开更多
关键词 multi-variable grey model (MGM(1 m)) backgroundvalue OPTIMIZATION multiple linear regression combined predic-tion model.
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A study of the mixed layer of the South China Sea based on the multiple linear regression 被引量:8
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作者 DUAN Rui YANG Kunde +1 位作者 MA Yuanliang HU Tao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第6期19-31,共13页
Multiple linear regression (MLR) method was applied to quantify the effects of the net heat flux (NHF), the net freshwater flux (NFF) and the wind stress on the mixed layer depth (MLD) of the South China Sea ... Multiple linear regression (MLR) method was applied to quantify the effects of the net heat flux (NHF), the net freshwater flux (NFF) and the wind stress on the mixed layer depth (MLD) of the South China Sea (SCS) based on the simple ocean data assimilation (SODA) dataset. The spatio-temporal distributions of the MLD, the buoyancy flux (combining the NHF and the NFF) and the wind stress of the SCS were presented. Then using an oceanic vertical mixing model, the MLD after a certain time under the same initial conditions but various pairs of boundary conditions (the three factors) was simulated. Applying the MLR method to the results, regression equations which modeling the relationship between the simulated MLD and the three factors were calculated. The equations indicate that when the NHF was negative, it was the primary driver of the mixed layer deepening; and when the NHF was positive, the wind stress played a more important role than that of the NHF while the NFF had the least effect. When the NHF was positive, the relative quantitative effects of the wind stress, the NHF, and the NFF were about i0, 6 and 2. The above conclusions were applied to explaining the spatio-temporal distributions of the MLD in the SCS and thus proved to be valid. 展开更多
关键词 mixed layer multiple linear regression South China Sea vertical mixing model
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基于PMF和APCS-MLR模型的会仙湿地沉积物重金属源解析及污染风险评价
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作者 刘涛 沈利娜 +1 位作者 于奭 秦金福 《环境科学》 北大核心 2025年第9期6024-6036,共13页
基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)... 基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)和正定矩阵因子分解(PMF)等多种方法,识别和定量解析污染源及贡献.结果表明:①8种重金属的平均含量均高于背景值,其中Cd超过《土壤环境质量-农用地土壤污染风险管控标准》(GB 15618-2018)筛选值.②地累积指数评价结果表明,Cd属于中度污染,Zn属于偏中度污染,Hg、Ni、Cr和Pb属于轻度污染,As和Cu属于无污染.③潜在风险指数评价结果表明,Cd(245.91)属于很强生态风险,Hg(134.59)属于强生态风险,其它元素均属于轻微生态风险;研究区综合生态风险指数均值为433.33,整体呈现出强的潜在生态风险.④APCS-MLR识别出4个污染源,分别为农业源、自然与农业源、大气沉降与生活源和未识别源(交通与农业源),贡献率分别为33.16%、15.75%、9.50%和41.59%;PMF识别出3个污染源,分别为大气沉降与生活源、自然与农业源和交通与农业源,贡献率分别为21.92%、35.24%和42.84%. 展开更多
关键词 沉积物 重金属 源解析 正定矩阵因子分解(PMF) 绝对主成分-多元线性回归(APCS-mlr)
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Application of Multiple Linear Regression and Manova to Evaluate Health Impacts Due to Changing River Water Quality 被引量:2
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作者 Sudevi Basu K. S. Lokesh 《Applied Mathematics》 2014年第5期799-807,共9页
Rivers are important systems which provide water to fulfill human needs. However, excessive human uses over the years have led to deterioration in quality of river causing, causing health problems from contaminated wa... Rivers are important systems which provide water to fulfill human needs. However, excessive human uses over the years have led to deterioration in quality of river causing, causing health problems from contaminated water. This study focuses on the application of statistical techniques, Multiple Linear Regression model and MANOVA to assess health impacts due to pollution in Cauvery river stretch in Srirangapatna. In this study, using Multiple Linear Regression, it is found that health impact level is 60.8% dependent on water quality parameters of BOD, COD, TDS, TC and FC. The t-statistics and their associated 2-tailed p-values indicate that COD and TDS produces health impacts compared to BOD, TC and FC, when their effects are put together across all the six sampling stations in Srirangapatna. Further Pearson correlation Matrix shows highly significant positive correlation amongst parameters across all stations indicating possibility of common sources of origin that might be anthropogenic. Also graphs are plotted for individual parameters across all stations and it reveals that COD and TDS values are significant across all sampling stations, though their values are higher in impact stations, causing health impacts. 展开更多
关键词 multiple linear regression model MANOVA t-Statistics BOD COD TDS TC FC
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基于MLR与ARDL的城市湖泊溶解氧浓度模拟 被引量:1
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作者 赵洪铖 杨菲 +2 位作者 周鹏 郭家诚 黄金柏 《人民珠江》 2025年第1期32-39,共8页
开展城市湖泊溶解氧模拟研究,对促进湖泊水质模拟研究的进展具有重要作用。选取近扬州市中心附近的一个城市湖泊作为研究的特定区域,利用2020年溶解氧、蓝绿藻浓度、水温、电导率、pH观测结果,构建多元线性回归模型和自回归分布滞后模型... 开展城市湖泊溶解氧模拟研究,对促进湖泊水质模拟研究的进展具有重要作用。选取近扬州市中心附近的一个城市湖泊作为研究的特定区域,利用2020年溶解氧、蓝绿藻浓度、水温、电导率、pH观测结果,构建多元线性回归模型和自回归分布滞后模型,对2020年(2020-01-01至2020-12-31)和该年各季度的溶解氧观测序列值进行模拟,结果表明:前者模拟精度相对较低,后者的模拟精度较高,后者对不同时段溶解氧模拟结果的决定系数R^(2)在0.75~0.99;2种模型对湖泊溶解氧的模拟均有较好的适用性,其中,自回归分布滞后模型对时段变化溶解氧序列模拟的适用性更好。 展开更多
关键词 城市湖泊 溶解氧浓度 多元线性回归模型 自回归分布滞后模型
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基于MLR-DE-LSTM的大坝变形串联组合预测模型 被引量:1
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作者 刘天翼 艾星星 张九丹 《中国农村水利水电》 北大核心 2025年第2期207-212,共6页
为了解决单一模型在大坝变形预测中可能带来的信息损失问题,将差分进化算法(DE)用于长短期记忆神经网络(LSTM)模型的参数优化,并结合多元线性回归(MLR)模型建立MLR-DE-LSTM串联组合模型。基于某重力坝的水平位移原型监测数据,对该模型... 为了解决单一模型在大坝变形预测中可能带来的信息损失问题,将差分进化算法(DE)用于长短期记忆神经网络(LSTM)模型的参数优化,并结合多元线性回归(MLR)模型建立MLR-DE-LSTM串联组合模型。基于某重力坝的水平位移原型监测数据,对该模型进行了验证。结果表明,DE算法可以有效提高LSTM模型的预测精度,LSTM模型可以有效挖掘MLR模型尚未完全解释的信息。相较于单一模型,组合模型在预测位移数据时具有更高的准确度和稳定性,组合模型在充分利用数据信息方面具有更大优势。研究结果为提高大坝变形预测精度提供了参考价值。 展开更多
关键词 大坝变形 差分进化算法 长短期记忆神经网络 多元线性回归 组合模型
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A Universal Selection Method in Linear Regression Models
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作者 Eckhard Liebscher 《Open Journal of Statistics》 2012年第2期153-162,共10页
In this paper we consider a linear regression model with fixed design. A new rule for the selection of a relevant submodel is introduced on the basis of parameter tests. One particular feature of the rule is that subj... In this paper we consider a linear regression model with fixed design. A new rule for the selection of a relevant submodel is introduced on the basis of parameter tests. One particular feature of the rule is that subjective grading of the model complexity can be incorporated. We provide bounds for the mis-selection error. Simulations show that by using the proposed selection rule, the mis-selection error can be controlled uniformly. 展开更多
关键词 linear regression model SELECTION multiple TESTS
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Establishment and Effect Evaluation of Prediction Models of Ozone Concentration in Baoding City
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作者 Xiangru KONG Jiajia ZHANG +2 位作者 Luntao YAO Tianning YANG Rongfang YANG 《Meteorological and Environmental Research》 2025年第3期44-50,共7页
Firstly,based on the data of air quality and the meteorological data in Baoding City from 2017 to 2021,the correlations of meteorological elements and pollutants with O_(3)concentration were explored to determine the ... Firstly,based on the data of air quality and the meteorological data in Baoding City from 2017 to 2021,the correlations of meteorological elements and pollutants with O_(3)concentration were explored to determine the forecast factors of forecast models.Secondly,the O_(3)-8h concentration in Baoding City in 2021 was predicted based on the constructed models of multiple linear regression(MLR),backward propagation neural network(BPNN),and auto regressive integrated moving average(ARIMA),and the predicted values were compared with the observed values to test their prediction effects.The results show that overall,the MLR,BPNN and ARIMA models were able to forecast the changing trend of O_(3)-8h concentration in Baoding in 2021,but the BPNN model gave better forecast results than the ARIMA and MLR models,especially for the prediction of the high values of O_(3)-8h concentration,and the correlation coefficients between the predicted values and the observed values were all higher than 0.9 during June-September.The mean error(ME),mean absolute error(MAE),and root mean square error(RMSE)of the predicted values and the observed values of daily O_(3)-8h concentration based on the BPNN model were 0.45,19.11 and 24.41μg/m 3,respectively,which were significantly better than those of the MLR and ARIMA models.The prediction effects of the MLR,BPNN and ARIMA models were the best at the pollution level,followed by the excellent level,and it was the worst at the good level.In comparison,the prediction effect of BPNN model was better than that of the MLR and ARIMA models as a whole,especially for the pollution and excellent levels.The TS scores of the BPNN model were all above 66%,and the PC values were above 86%.The BPNN model can forecast the changing trend of O_(3)concentration more accurately,and has a good practical application value,but at the same time,the predicted high values of O_(3)concentration should be appropriately increased according to error characteristics of the model. 展开更多
关键词 Ozone(O_(3)) multiple linear regression model Back propagation neural network model Auto regressive integrated moving average model TS
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基于CEEMDAN及BiGRU-MLR模型的短期负荷预测方法
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作者 王鸿玺 申洪涛 +2 位作者 冯波 王洪莹 阎超 《河北电力技术》 2025年第5期32-40,共9页
随着新型电力系统的快速发展,用户用电行为呈现出多样化和不确定性,实现短期电力负荷的高精度预测已成为保障系统稳定运行的关键。现有短期负荷预测(short-term load forecasting,STLF)方法在处理复杂的非线性和非平稳性数据时存在一定... 随着新型电力系统的快速发展,用户用电行为呈现出多样化和不确定性,实现短期电力负荷的高精度预测已成为保障系统稳定运行的关键。现有短期负荷预测(short-term load forecasting,STLF)方法在处理复杂的非线性和非平稳性数据时存在一定的局限性。为此,提出了一种融合自适应噪声完备集合经验模态分解(complete ensemble empirical model decomposition with adaptive noise,CEEMDAN)、双向门控循环单元(bidirectional gated recurrent unit,BiGRU)与多元线性回归(Multiple Linear Regression,MLR)的混合短期负荷预测模型。首先,利用Spearman秩相关系数分析筛选出对电力负荷影响显著的气象和时间因素。其次,将影响因素与电力负荷数据进行自适应噪声完备集合经验模态分解,通过引入过零率将各分量重构为高频分量和低频分量。然后,针对高频分量构建双向门控循环单元模型进行预测,对于低频分量建立多元线性回归模型进行预测。最后,将各模型所得预测值进行线性叠加,获得最终的预测结果。仿真结果表明,所提方法在多个实际数据集上显著优于传统长短期记忆网络(long short-term memory,LSTM)、门控循环单位(gated recurrent unit,GRU)及其他结合自适应噪声完备集合经验模态分解的预测方法,能够有效提高短期电力负荷预测的精度,具有广泛的应用前景。 展开更多
关键词 短期电力负荷预测 自适应噪声完备集合经验模态分解 高频分量 双向门控循环单元 低频分量 多元线性回归
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基于APCS-MLR和PMF的污灌与工业复合区农田土壤重金属来源解析 被引量:8
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作者 刘德新 孟凡磊 +2 位作者 段海静 李一蒙 马建华 《环境科学》 EI CAS CSCD 北大核心 2024年第8期4812-4824,共13页
基于开封市污灌与工业复合区农田表土样品,测定8种重金属(Cr、Ni、Cu、Zn、Cd、Pb、As和Hg)含量,利用绝对因子得分-多元线性回归(APCS-MLR)模型和正定矩阵因子分解(PMF)模型,结合相关性分析和系统聚类分析对土壤重金属来源和贡献率进行... 基于开封市污灌与工业复合区农田表土样品,测定8种重金属(Cr、Ni、Cu、Zn、Cd、Pb、As和Hg)含量,利用绝对因子得分-多元线性回归(APCS-MLR)模型和正定矩阵因子分解(PMF)模型,结合相关性分析和系统聚类分析对土壤重金属来源和贡献率进行解析.结果表明:①研究区ω(Cr)、ω(Ni)、ω(Cu)、ω(Zn)、ω(Cd)、ω(Pb)、ω(As)和ω(Hg)平均值分别为52.19、25.00、42.03、323.53、1.79、53.45、9.43和0.20 mg·kg^(-1),其中Cr、Ni和As低于潮土背景值,Cu、Zn、Cd、Pb和Hg高于潮土背景值.②8种重金属有4种来源:自然源、农业污水灌溉源、工业大气沉降源和交通运输源,Cr和Ni主要为自然源,Cu、Zn、Cd和Pb主要为农业污水灌溉和交通运输,As主要为自然源和农业污水灌溉,Hg主要为工业大气沉降.③APCS-MLR和PMF源解析结果表明工农业活动是研究区土壤重金属的主要来源.研究区9个采样小区APCS-MLR平均贡献率为76.01%(自然源和农业污水灌溉源)、22.71%(工业大气沉降源和交通运输源)和1.28%(未知源),PMF平均贡献率为59.66%(自然源和农业污水灌溉源)和40.34%(工业大气沉降源和交通运输源),其中LZ、XZ、NLT、PT、YLZ和BC的两种模型源解析结果基本一致,WL在APCS-MLR模型更优,SG和QT在PMF模型更优.研究结果可为土壤重金属污染防治和环境修复提供科学依据. 展开更多
关键词 污灌与工业复合区 农田土壤 绝对因子得分-多元线性回归(APCS-mlr) 正定矩阵因子分解(PMF) 源解析
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基于APCS-MLR模型的城市绿地土壤重金属污染源解析研究 被引量:6
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作者 刘春英 曹依 +1 位作者 李嘉薇 肖长江 《干旱区资源与环境》 CSSCI CSCD 北大核心 2024年第7期146-154,共9页
为探究南昌市绿地土壤重金属的污染状况及污染来源,利用地累积污染指数和潜在生态风险指数评价重金属的污染程度,并采用APCS-MLR模型定量解析土壤重金属的污染来源及其贡献率。研究结果表明,Cu、Pb、Zn、Cd和Cr的平均含量是江西省土壤... 为探究南昌市绿地土壤重金属的污染状况及污染来源,利用地累积污染指数和潜在生态风险指数评价重金属的污染程度,并采用APCS-MLR模型定量解析土壤重金属的污染来源及其贡献率。研究结果表明,Cu、Pb、Zn、Cd和Cr的平均含量是江西省土壤背景值的1.32、1.92、2.26、2.03和1.04倍。Cu、Pb、Zn、Cd和Cr的地累积指数为-0.43、0.07、0.33、0.22和-0.66,Zn、Pb、Cd处于未污染到中等程度污染水平,Pb和Zn的高值区位于市中心区域以及西北部和东部开发区,Cd含量高值区位于西北部和东部产业基地周边。Cu和Cr属于未污染水平。综合潜在生态风险指数为82.96,处于低生态风险水平,但Cd的生态风险指数为60.88,属于中等生态风险水平。由污染源解析可知,交通源对Cu、Zn、Pb的贡献率分别为52.29%、64.41%和38.01%,工业和农业混合源对Cd、Zn的贡献率分别为52.78%和86.33%,自然源对Cr、Cu的贡献率分别为83.72%和45.87%。南昌市绿地土壤重金属含量受交通和工农业活动影响较大,应重点加强交通管控,优化产业结构,降低Zn、Pb、Cd的生态风险水平。 展开更多
关键词 土壤重金属 空间分布特征 污染源解析 APCS-mlr模型 南昌市
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基于APCS-MLR模型和地理探测器的煤矸山周边土壤污染溯源解析和影响因素分析 被引量:8
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作者 马杰 秦启荧 +2 位作者 王胜蓝 李名升 封雪 《环境科学》 EI CAS CSCD 北大核心 2024年第12期7157-7165,共9页
以重庆市煤矸山周边土壤为研究对象,运用绝对因子得分-多元线性回归(APCS-MLR)模型对土壤重金属开展源解析,考虑坡度、高程、土壤点位与煤矸山、居民点和主干道距离等5个环境因子,运用地理探测器开展土壤影响因素分析.结果表明,研究区... 以重庆市煤矸山周边土壤为研究对象,运用绝对因子得分-多元线性回归(APCS-MLR)模型对土壤重金属开展源解析,考虑坡度、高程、土壤点位与煤矸山、居民点和主干道距离等5个环境因子,运用地理探测器开展土壤影响因素分析.结果表明,研究区土壤ω(Cd)、ω(Hg)、ω(Pb)、ω(Cr)、ω(Cu)、ω(Zn)和ω(Ni)均值分别为1.33、0.29、32.9、142、68.8、118和54.6 mg·kg^(-1),Cd是首要污染物. APCS-MLR模型源解析结果表明,研究区土壤受矿业源影响,贡献率为37.1%,污染因子以Cd、Hg和Pb为主;受农业和交通源影响,贡献率为36.2%,污染因子以Cu、Zn和Ni为主;受自然源影响,贡献率为26.7%,污染因子以Cr为主.地理探测器分析结果表明,Cd、Hg和Pb在环境因子“与煤矸山距离”解释力最强,Cr、Cu、Zn和Ni在环境因子“与居民点距离”解释力最强,因子两两交互后,影响力均有提升,说明土壤重金属空间含量分布特征受多因子复合影响. APCS-MLR模型和地理探测器联用,可以在源解析和影响因素分析上相互验证,使解析结果更加全面、准确和可靠. 展开更多
关键词 土壤 重金属 绝对因子得分-多元线性回归(APCS-mlr)模型 地理探测器 源解析 影响因子
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Predicting the Acute Toxicity of Aromatic Amines by Linear and Nonlinear Regression Methods 被引量:5
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作者 张晓龙 周志祥 +3 位作者 刘阳华 范雪兰 李捍东 王建涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第2期244-252,共9页
In current paper, a quantitative structure-activity relationship (QSAR) study was performed for the prediction of acute toxicity of aromatic amines. A set of 56 compounds was randomly divided into a training set of ... In current paper, a quantitative structure-activity relationship (QSAR) study was performed for the prediction of acute toxicity of aromatic amines. A set of 56 compounds was randomly divided into a training set of 46 compounds and a test set of 10 compounds. The electronic and topological descriptors computed by the Scigress package and Dragon software were used as predictor variables. Multiple linear regression (MLR) and support vector machine (SVM) were utilized to build the linear and nonlinear QSAR models, respectively. The obtained models with five descriptors show strong predictive ability. The linear model fits the training set with R2 = 0.71, with higher SVM values of R2 = 0.77. The validation results obtained from the test set indicate that the SVM model is comparable or superior to that obtained by MLR, both in terms of prediction ability and robustness. 展开更多
关键词 aromatic amines acute toxicity quantitative structure-activity relationship(QSAR) support vector machine (SVM) multiple linear regression mlr
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Gamma generalized linear model to investigate the effects of climate variables on the area burned by forest fire in northeast China 被引量:2
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作者 Futao Guo Guangyu Wang +3 位作者 John L. Innes Xiangqing Ma Long Sun Haiqing Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第3期545-555,共11页
The purpose of this study was to determine a suitable model for investigating the effects of climate factors on the area burned by forest fire in the Tahe forest region, Daxing'an Mountains, in northeast China. The r... The purpose of this study was to determine a suitable model for investigating the effects of climate factors on the area burned by forest fire in the Tahe forest region, Daxing'an Mountains, in northeast China. The response variables were the area burned by lightning- caused fire, human-caused fire, and total burned area. The predictor variables were nine climate variables collected from the local weather station. Three regression models were utilized, including multiple linear regression, log- linear model (log-transformation on both response and predictor variables), and gamma-generalized linear model. The goodness-of-fit of the models were compared based on model fitting statistics such as R2, AIC, and RMSE. The results revealed that the gamma-generalized linear model was generally superior to both multiple linear regressionmodel and log-linear model for fitting the fire data. Further, the best models were selected based on the criteria that the climate variables were statistically significant at at = 0.05. The gamma best models indicated that maximum wind speed, precipitation, and days that rainfall greater than 0.1 mm had significant impacts on the area burned by the lightning-caused fire, while the mean temperature and minimum relative humidity were the .main drivers of the burned area caused by human activities. Overall, the total burned area by forest fire was significantly influenced by days that rainfall greater than 0.1 mm and minimum rela- tive humidity, indicating that the moisture condition of forest stands determine the burned area by forest fire. 展开更多
关键词 Lightning-caused fire Human-caused fire multiple linear regression Log-linear model Daxing'anmountains
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基于RF和MLR的土壤重金属影响因素分析及生物有效性预测 被引量:4
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作者 潘泳兴 陈盟 +1 位作者 王櫹橦 刘楠 《农业环境科学学报》 CAS CSCD 北大核心 2024年第4期845-857,共13页
为探究影响土壤中重金属累积和生物有效性的因素,以桂北地区某铅锌矿流域为研究对象,综合运用单因子指数法、风险评价编码法(RAC)、多元线性回归模型(MLR)和随机森林模型(RF)进行土壤重金属(Pb、Zn、Cu和Cr)累积影响因素分析及生物有效... 为探究影响土壤中重金属累积和生物有效性的因素,以桂北地区某铅锌矿流域为研究对象,综合运用单因子指数法、风险评价编码法(RAC)、多元线性回归模型(MLR)和随机森林模型(RF)进行土壤重金属(Pb、Zn、Cu和Cr)累积影响因素分析及生物有效性预测。结果表明:研究区Cr含量无超标且空间分布相对均匀(变异系数为0.51);Cu、Pb和Zn的含量均值(分别为52.58、280.31 mg·kg^(-1)和654.71 mg·kg^(-1))均大于广西西江流域土壤重金属背景值,在思的河山前和地下河入口处全量和生物有效性均较大,对土壤生态环境具有一定风险;对于重金属全量分布和生物有效态的影响因素,阳离子交换量(CEC)、黏粒(Clay)、土壤有机质(SOM)和铁铝氧化物对Cr影响较大,SOM、Clay、pH和铁铝氧化物对Cu影响较大,pH、电导率(EC)和Clay对Pb影响较大,CEC、pH、土壤质地和铁铝氧化物对Zn影响较大;生物有效性预测结果显示RF和MLR均可较好地预测土壤重金属的全量与次生相,其中RF预测的R2区间为0.44~0.93,MLR预测的R2区间为0.30~0.72,RF预测结果表现更为准确。 展开更多
关键词 土壤重金属 影响因素 生物有效性预测 随机森林模型(RF) 多元线性回归模型(mlr)
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基于APCS-MLR模型的煤矿开采对地下水的影响定量识别
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作者 刘基 高敏 +1 位作者 陈引锋 靳德武 《中国煤炭地质》 2024年第10期45-51,44,共8页
中国煤炭与水资源储量呈逆向分布,煤炭基地水资源相对短缺,生态环境脆弱。随着煤炭资源的大规模和高强度开发,区域地下水环境问题越发凸显。为定量识别煤矿开采对地下水的影响程度,以蒙东能源基地某矿区为例,通过采集矿区周边地下水化... 中国煤炭与水资源储量呈逆向分布,煤炭基地水资源相对短缺,生态环境脆弱。随着煤炭资源的大规模和高强度开发,区域地下水环境问题越发凸显。为定量识别煤矿开采对地下水的影响程度,以蒙东能源基地某矿区为例,通过采集矿区周边地下水化学样品进行测试,系统分析了研究区地下水水化学特征,采用相关性分析、PCA等多元统计方法确定了地下水的影响因子,据此建立了基于绝对因子得分-多元线性回归法(APCS-MLR)的定量识别模型,对研究区地下水受煤矿开采的影响贡献进行了计算分析。结果显示:研究区浅层地下水pH值为6.52~7.86,平均7.27,TDS为126.14~2240.34mg/L,平均为638.18 mg/L。主要阳离子平均含量Na^(+)>Ca^(2+)>Mg^(2+)>K^(+),主要阴离子平均含量HCO_(3)^(-)>Cl^(-)>SO_(4)^(2-)>NO_(3)^(-)。其中Cl^(-)和SO_(4)^(2-)的含量分别为4.25~779.77 mg/L和0~483.20 mg/L,其变异系数均大于100%。SO_(4)^(2-)与Na^(+)、Ca^(+)、Mg^(2+)、Cl^(-)存在显著正相关关系(r>0.72,P<0.01),TDS与SO_(4)^(2-)、Na^(+)、Ca^(+)、Mg^(2+)、Cl^(-)存在显著正相关关系。多项指标显示研究区地下水水质已经受到了煤矿开采的影响。主成分分析(PCA)解析了4个地下水影响因子,分别为煤炭开采影响因子、自然因素的硅酸盐溶解因子、自然因素的反硝化作用和农业活动的化肥使用,其占总荷载的37.061%、16.067%、14.807%和8.775%。以SO_(4)^(2-)作为煤矿开采对地下水影响的表征因子,构建了SO_(4)^(2-)来源计算分析的APCS-MLR定量识别模型。通过最小二乘法计算得到模型的各项参数,确定SO_(4)^(2-)的实际浓度和预测浓度拟合曲线为y=0.9716x+2.9702(R^(2)=0.9759),说明构建的回归方程符合实际,效果良好。据此计算了4个地下水影响因子的贡献比分别为79.3%、6.06%、2.00%和9.96%,其他未识别的因子占比2.67%。分析了煤矿开采影响地下水水质的主要方式为形成降落漏斗影响周边水化学场以及外排含有特殊组分的矿井水进而影响地下水水质。因此需要采取合理措施控制煤矿开采产生的降落漏斗范围继续扩大,必要时对已经产生的漏斗进行恢复治理,同时加强对高盐、高SO_(4)^(2-)矿井水的处理和排放管理,研究成果可为煤炭绿色开发和环境高质量发展提供技术支持。 展开更多
关键词 煤矿开采 地下水 绝对因子得分-多元线性回归(APCS-mlr) 定量识别 影响因子
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Regression analysis and its application to oil and gas exploration:A case study of hydrocarbon loss recovery and porosity prediction,China
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作者 Yang Li Xiaoguang Li +3 位作者 Mingyu Guo Chang Chen Pengbo Ni Zijian Huang 《Energy Geoscience》 EI 2024年第4期240-252,共13页
In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not... In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery. 展开更多
关键词 regression analysis Oil and gas exploration multiple linear regression model Nonlinear regression model Hydrocarbon loss recovery Porosity prediction
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Analysis and Evaluation of Housing Price Factors Using Mathematical Modeling
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作者 Xing Lyu 《Proceedings of Business and Economic Studies》 2024年第6期17-23,共7页
In recent years,the real estate industry has achieved significant progress,driving the development of related sectors and playing a crucial role in economic growth.However,rapid real estate market expansion has led to... In recent years,the real estate industry has achieved significant progress,driving the development of related sectors and playing a crucial role in economic growth.However,rapid real estate market expansion has led to challenges,particularly concerning housing prices,which have drawn widespread societal attention.This article explores the theories of housing prices,analyzes factors influencing them,and conducts an empirical investigation of the impact of representative factors on ordinary residential prices.Using regression analysis and the entropy weight method,a mathematical model was developed to examine how various factors affect housing prices. 展开更多
关键词 Mathematical modeling regression analysis Housing price Formation factors multiple linear regression H ypothesis testing multiple decision coefficients
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