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Cloud removal of remote sensing image based on multi-output support vector regression 被引量:3
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作者 Gensheng Hu Xiaoqi Sun +1 位作者 Dong Liang Yingying Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1082-1088,共7页
Removal of cloud cover on the satellite remote sensing image can effectively improve the availability of remote sensing images. For thin cloud cover, support vector value contourlet transform is used to achieve multi-... Removal of cloud cover on the satellite remote sensing image can effectively improve the availability of remote sensing images. For thin cloud cover, support vector value contourlet transform is used to achieve multi-scale decomposition of the area of thin cloud cover on remote sensing images. Through enhancing coefficients of high frequency and suppressing coefficients of low frequency, the thin cloud is removed. For thick cloud cover, if the areas of thick cloud cover on multi-source or multi-temporal remote sensing images do not overlap, the multi-output support vector regression learning method is used to remove this kind of thick clouds. If the thick cloud cover areas overlap, by using the multi-output learning of the surrounding areas to predict the surface features of the overlapped thick cloud cover areas, this kind of thick cloud is removed. Experimental results show that the proposed cloud removal method can effectively solve the problems of the cloud overlapping and radiation difference among multi-source images. The cloud removal image is clear and smooth. 展开更多
关键词 remote sensing image cloud removal support vector regression multi-OUTPUT
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Estimating Wheat Grain Protein Content Using Multi-Temporal Remote Sensing Data Based on Partial Least Squares Regression 被引量:4
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作者 LI Cun-jun WANG Ji-hua +4 位作者 WANG Qian WANG Da-cheng SONG Xiao-yu WANG Yan HUANGWen-jiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第9期1445-1452,共8页
Estimating wheat grain protein content by remote sensing is important for assessing wheat quality at maturity and making grains harvest and purchase policies. However, spatial variability of soil condition, temperatur... Estimating wheat grain protein content by remote sensing is important for assessing wheat quality at maturity and making grains harvest and purchase policies. However, spatial variability of soil condition, temperature, and precipitation will affect grain protein contents and these factors usually cannot be monitored accurately by remote sensing data from single image. In this research, the relationships between wheat protein content at maturity and wheat agronomic parameters at different growing stages were analyzed and multi-temporal images of Landsat TM were used to estimate grain protein content by partial least squares regression. Experiment data were acquired in the suburb of Beijing during a 2-yr experiment in the period from 2003 to 2004. Determination coefficient, average deviation of self-modeling, and deviation of cross- validation were employed to assess the estimation accuracy of wheat grain protein content. Their values were 0.88, 1.30%, 3.81% and 0.72, 5.22%, 12.36% for 2003 and 2004, respectively. The research laid an agronomic foundation for GPC (grain protein content) estimation by multi-temporal remote sensing. The results showed that it is feasible to estimate GPC of wheat from multi-temporal remote sensing data in large area. 展开更多
关键词 grain protein content agronomic parameters multi-TEMPORAL LANDSAT partial least squares regression
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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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Multi-Step Model Predictive Control Based on Online Support Vector Regression Optimized by Multi-Agent Particle Swarm Optimization Algorithm 被引量:2
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作者 TANG Xianlun LIU Nianci +1 位作者 WAN Yali GUO Fei 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第5期607-612,共6页
As optimization of parameters affects prediction accuracy and generalization ability of support vector regression(SVR) greatly and the predictive model often mismatches nonlinear system model predictive control,a mult... As optimization of parameters affects prediction accuracy and generalization ability of support vector regression(SVR) greatly and the predictive model often mismatches nonlinear system model predictive control,a multi-step model predictive control based on online SVR(OSVR) optimized by multi-agent particle swarm optimization algorithm(MAPSO) is put forward. By integrating the online learning ability of OSVR, the predictive model can self-correct and adapt to the dynamic changes in nonlinear process well. 展开更多
关键词 online support VECTOR regression (OSVR) model PREDICTIVE CONTROLLER (MPC) multi-AGENT particleswarm optimization (MAPSO) nonlinear systems
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 multi Spectral Instrument(MSI) logistic regression Songnen Plain China
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Improved the Prediction of Multiple Linear Regression Model Performance Using the Hybrid Approach: A Case Study of Chlorophyll-a at the Offshore Kuala Terengganu, Terengganu
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作者 Muhamad Safiih Lola Mohd Noor Afiq Ramlee +4 位作者 G. Sugan Gunalan Nurul Hila Zainuddin Razak Zakariya MdSuffian Idris Idham Khalil 《Open Journal of Statistics》 2016年第5期789-804,共17页
Efficiency and precision in prediction of Chlorophyll-a using this model is still a pandemic among researchers, due to the natural conditions in ocean water systems itself, which involved chemical, biological and phys... Efficiency and precision in prediction of Chlorophyll-a using this model is still a pandemic among researchers, due to the natural conditions in ocean water systems itself, which involved chemical, biological and physical processes and interaction among them may affect the model performance drastically. Thus, to overcome this problem as well as to improve the strength of MLR, we proposed a hybrid approach, i.e., an Artificial Neural Network to the MLR coins as Artificial Neural Network-Multiple Linear Regression (ANN-MLR). To investigate the performance of the proposed model, we compared Multiple Linear Regression (MLR), Artificial Neural Network (ANN) and proposed hybrid Artificial Neural Network and Multiple Linear Regression (ANN-MLR) in the prediction of chlorophyll-a (chl-a) concentration by statistical measurement which are MSE and MAE. Achieving our objectives of study, we used 4 parameters, i.e. temperature (°C), pH, salinity (ppt), DO (ppm) at the Offshore Kuala Terengganu, Terengganu, Malaysia. The results showed that our proposed model can improve the performance of the model as compared to ANN and MLR due to small errors generated, error reduced, and increased the correlation coefficient for all parameters in both MSE and MAE, respectively. Thus, this result indicated that our proposed model is efficient, precise and almost perfect correlation as compared to ANN and MLR. 展开更多
关键词 multi Linear regression Artificial Neural Network ANN-MLR CHLOROPHYLL-A CORRELATION
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The Research on and Application of the Multi-regression Technique in the Course of the Marketing Decision-making of Enterprises
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作者 QIU Xiao-dong, ZHAO Ping (School of Economics & Management, Tsinghua University, Beijing 100084 , China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期221-222,共2页
The reformation of the economy system has led the f un ctional department and status of the enterprises into a variable state. Under th e condition of the market economy, the kernel of the enterprises’ functional dep... The reformation of the economy system has led the f un ctional department and status of the enterprises into a variable state. Under th e condition of the market economy, the kernel of the enterprises’ functional dep artment has diverted to that of marketing decision-making, which face to market and meet with the need of consumption. Assuredly, the kernel of marketing decis ion-making is to prognosticate the future market demand of the production of en terprises accurately, so that it can ensure and realize the maximum of the enter prises’ profit increase. Using empirical research and the multi-regression technique, this paper ana lyzes the enterprises’ production demand forecast of the GMC (Global Management Challenge, held every year globally) and changes most of uncontrollable factors of demand forecast to the controllable ones of the enterprises. The method we us ed to forecast demand by using the multi-regression technique is as follows: 1. Look for the main factors which influence the demand of productions; 2. Establish the regression model; 3. Using the historical data, find the resolution of the correlative index an d do the prominent test; 4. Analyze and compare, regression, adjust parameter and optimize the regress ion model. Our method will make the forecast data closer to the actual prices of the future market requirement quantity in the production marketing decision-making of the enterprises and realize the optimizing combination and the working object w ith the minimum of the cost and the maximum of the profit. And it can ensure the realization of the equity maximum of the enterprises and increase the lifecycle of the production. 展开更多
关键词 marketing decision-making demand forecast corr elative index multi-regression technique
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ENHANCING GROUND RESOLUTION OF TM6 BASED ON MULTI-VARIATE REGRESSION MODEL AND SEMI-VARIOGRAM FUNCTION
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作者 MA Hongchao LI Deren 《Geo-Spatial Information Science》 2001年第1期43-49,共7页
It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resoluti... It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resolution compared with the other six bands.Nevertheless,it is useful in the study of rock spectrum reflection,geothermal resources exploration,etc.To improve the ground resolution of TM6 to the level as that of the other six bands is a problem .This paper presents an algorithm based on the combination of multivariate regression model with semivariogram function which can improve the ground resolution of TM6 by "fusing" the data of other six bands.It includes the following main steps: (1) testing the correlation between TM6 and one of TM15,7.If the correlation coefficient between TM6 and another one is greater than a given threshold value,then select the band to the regression analysis as an argument.(2) calculating the size of the template window within which some parameters needed by the regression model will be calculated; (3) replacing the original pixel values of TM6 by those obtained by regression analysis; (4) using image entropy as a measurement to evaluate the quality of the fused image of TM6.The basic mechanism of the algorithm is discussed and the V C ++ program for implementing this algorithm is also presented.A simple application example is given in the last part of this paper,showing the effectiveness of the algorithm. 展开更多
关键词 multi-variate regression model semi-variogram FUNCTION image fusion TEMPLATE WINDOW V C++ PROGRAMMING
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Monthly Electricity Consumption Forecast Based on Multi-Target Regression
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作者 Haiming Li Ping Chen 《Journal of Computer and Communications》 2019年第7期231-242,共12页
Urban grid power forecasting is one of the important tasks of power system operators, which helps to analyze the development trend of the city. As the demand for electricity in various industries is affected by many f... Urban grid power forecasting is one of the important tasks of power system operators, which helps to analyze the development trend of the city. As the demand for electricity in various industries is affected by many factors, the data of relevant influencing factors are scarce, resulting in great deviations in the accuracy of prediction results. In order to improve the prediction results, this paper proposes a model based on Multi-Target Tree Regression to predict the monthly electricity consumption of different industrial structures. Due to few data characteristics of actual electricity consumption in Shanghai from 2013 to the first half of 2017. Thus, we collect data on GDP growth, weather conditions, and tourism season distribution in various industries in Shanghai, model and train the electricity consumption data of different industries in different months. The multi-target tree regression model was tested with actual values to verify the reliability of the model and predict the monthly electricity consumption of each industry in the second half of 2017. The experimental results show that the model can accurately predict the monthly electricity consumption of various industries. 展开更多
关键词 Forecasting multi-TARGET TREE regression ELECTRICITY MONTHLY ELECTRICITY CONSUMPTION PREDICT
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Multi-Response Variable Optimization in Sensor Drift Monitoring System Using Support Vector Regression
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作者 In-Yong Seo Bok-Nam Ha Won Nam Koong 《通讯和计算机(中英文版)》 2012年第7期752-758,共7页
关键词 支持向量回归 传感器漂移 变量优化 监控系统 传感器信号 灵敏度 正常运行 安全操作
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Logistic Regression在我国河流水系氮污染研究中的应用 被引量:11
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作者 高学民 陈静生 王立新 《环境科学学报》 CAS CSCD 北大核心 2000年第6期676-681,共6页
对四川省岷江、沱江及嘉陵江流域和江西省的赣江流域及鄱阳湖地区共 1 70多个水文站的数据进行了相关分析和多元回归分析 .结果表明 ,河流水中硝态氮浓度与年降雨量、人口密度、氮肥施用量、牲畜饲养量、农作物及粮食作物种植面积等因... 对四川省岷江、沱江及嘉陵江流域和江西省的赣江流域及鄱阳湖地区共 1 70多个水文站的数据进行了相关分析和多元回归分析 .结果表明 ,河流水中硝态氮浓度与年降雨量、人口密度、氮肥施用量、牲畜饲养量、农作物及粮食作物种植面积等因素有较好的相关性 .以以上数据资料为基础 ,将河流水NO3- N的浓度划分为背景浓度 (<0 7mg/L)、受人类活动的显著影响的NO3- N浓度 (>3 0mg/L)以及中间类 (0 7— 3 0mg/L)进行LogisticRegression分析 ,两个Logistic模型的准确度分别达 82 46%和 89 1 9% .运用Logistic模型对整个长江流域河流水中NO3- N浓度进行估计 ,结果与实测值基本相符合 . 展开更多
关键词 河流水 硝态氮 多元回归分析 污染源
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Logistic Regression Analysis of Influencing Factors on Serum ALT and HCV RNA Changes in Patients with Chronic Hepatitis C
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作者 Cheng-bao Wang Jian-jie Chen +3 位作者 Hong-ming Nie Feng Gao Hua Lv Hong-ding Li 《国际感染病学(电子版)》 CAS 2012年第2期80-83,共4页
Objective This study was undertaken to investigate the influencing factors on serum ALT level and hepatitis C virus(HCV)RNA titer in chronic hepatitis C(CHC)patients.Methods All patients enrolled into this study were ... Objective This study was undertaken to investigate the influencing factors on serum ALT level and hepatitis C virus(HCV)RNA titer in chronic hepatitis C(CHC)patients.Methods All patients enrolled into this study were anti-HCV positive.Retrospective tracing method was applied to detect serum ALT level and HCV RNA titer and to collect general information of the patients such as genders,age groups,interferon medication history,infection pathways,height and weight.Then the multi-factor analysis was adopted with the application of binominal logistic regression mode.Results The abnormal rate of ALT level was positively correlated to HCV RNA and gender while negatively correlated to interferon medication history and age group,with Wald value of the 4 factors as 39.604,11.823,18.991 and 7.389,respectively.The positive rate of HCV RNA was negatively correlated to interferon medication history and gender while positively correlated to ALT level,with corresponding Wald value of the 3 factors as81.394,7.618 and 27.562,respectively.Conclusions The normal ALT level in HCV infected patients was associated with viral load,age,gender and interferon medication history,while the normal rate of HCV RNA titer was closely associated with gender,interferon medication history and ALT level. 展开更多
关键词 multi-factor logistic regression analysis Hepatitis C virus Chronic Hepatitis C Serum ALT level HCV RNA
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不确定环境下多机器人协同区域搜索与覆盖方法
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作者 曹凯 陈阳泉 +3 位作者 魏云博 高嵩 阎坤 丁羽菲 《北京航空航天大学学报》 北大核心 2026年第2期404-414,共11页
针对未知环境下的多机器人协同搜索和源定位问题,提出一种基于Voronoi图的分布式协同区域搜索和覆盖方法。该方法考虑机器人的实际尺寸和定位误差引起的碰撞问题,根据每个机器人的定位不确定性半径构造Voronoi缓冲区域以保障安全性。利... 针对未知环境下的多机器人协同搜索和源定位问题,提出一种基于Voronoi图的分布式协同区域搜索和覆盖方法。该方法考虑机器人的实际尺寸和定位误差引起的碰撞问题,根据每个机器人的定位不确定性半径构造Voronoi缓冲区域以保障安全性。利用稀疏高斯过程回归和引入不确定正则项的质心Voronoi划分(CVT)算法重建未知浓度场的分布,并进行协同覆盖;提出一种自适应环境探索策略,实现无先验信息下的环境探索。仿真实验表明:所提方法能够快速完成对未知环境的探索,并准确定位到污染源的位置。 展开更多
关键词 多机器人 VORONOI划分 源定位 稀疏高斯过程回归 协同覆盖
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地级市尺度下中国物流企业空间格局演化特征及影响因素
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作者 戢晓峰 李子歆 +2 位作者 曹瑞 李武 陈方 《干旱区地理》 北大核心 2026年第1期176-185,共10页
物流企业在区域经济中发挥着至关重要的作用,其分布情况直接影响区域经济的资源配置和市场竞争力,研究地级市物流企业空间格局演化特征及影响因素,有助于揭示物流企业集聚的形成机制。基于2006—2023年中国地级市物流企业地理位置数据,... 物流企业在区域经济中发挥着至关重要的作用,其分布情况直接影响区域经济的资源配置和市场竞争力,研究地级市物流企业空间格局演化特征及影响因素,有助于揭示物流企业集聚的形成机制。基于2006—2023年中国地级市物流企业地理位置数据,运用核密度分析、标准差椭圆、平均最近邻、空间自相关等空间分析方法,获取地级市尺度下物流企业时空格局及演化特征,并使用多尺度地理加权回归模型分析影响物流企业空间格局的因素及其空间分异特征。结果表明:(1)中国物流企业空间分布始终保持集聚特征,其空间格局经历了“一核带动、多点集聚”转变为“多核”,再逐渐转变为“双核”的演化过程,且存在廊道扩散和邻近扩散效应。(2)物流企业发展存在显著的正向溢出效应,发展较快的城市能够带动周边城市的发展。欠发达城市受发达城市的“虹吸效应”影响,处于“虹吸潮”的低洼地带具有显著的负向溢出效应。(3)第三产业就业人数和进出口总额为物流企业空间格局的主要影响因素。其中,进出口总额、外资企业数量为全局影响因素;第三产业就业人数和人均GDP为局部影响因素。 展开更多
关键词 物流企业 空间演化 影响因素 多尺度地理加权回归 地级市 产业集聚
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珠三角地区知识复杂性的格局演化与影响因素研究
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作者 刘玉亭 姚维新 陈清怡 《地理科学进展》 北大核心 2026年第3期542-558,共17页
知识复杂性是衡量区域创新质量、预测经济增长潜力的核心变量,但现有研究对其在镇(街)等微观尺度下的时空异质性特征与影响因素分析不足。论文基于1990—2022年珠三角镇(街)尺度的发明专利数据测度知识复杂性指数(knowledge complexity ... 知识复杂性是衡量区域创新质量、预测经济增长潜力的核心变量,但现有研究对其在镇(街)等微观尺度下的时空异质性特征与影响因素分析不足。论文基于1990—2022年珠三角镇(街)尺度的发明专利数据测度知识复杂性指数(knowledge complexity index,KCI),结合空间自相关及多尺度地理加权回归模型,探究知识复杂性的时空动态演化规律。结果表明:①知识领域总体呈现“ICT主导—多元协同”的演化特征,生物医药与新能源等战略性新兴产业知识领域形成突破性布局;②知识复杂性的空间格局遵循“核心集聚—边缘滞后”的梯度分异规律,由早期散点式逐步演化为以广深科技创新走廊为核心区域的多中心网络结构;③知识结构驱动效应存在显著时空异质性,相关多样性通过技术关联持续强化知识复杂性的正向效应,而非相关多样性呈现先促进后分化的阶段性演变规律,在初期对珠三角地区知识复杂化具有普遍促进作用,后期仅在广佛核心区发挥正向作用;④创新要素的空间配置对知识复杂性分异有关键作用。地方政府需兼顾梯度适配策略,核心区应强化技术关联网络,外围区需优先培育集群的专业化优势。研究可为珠三角地区破解低端锁定、重塑高质量创新格局、构建空间协同机制等提供科学参考。 展开更多
关键词 知识复杂性 知识基础 多样性 多尺度地理加权回归 珠三角地区
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基于CT影像学评估的颌面颈部间隙感染并发症预测模型及临床应用
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作者 侯大为 苟学立 +1 位作者 边勤疆 刘瑞敏 《兰州大学学报(医学版)》 2026年第2期39-43,52,共6页
目的构建并验证一个结合计算机断层扫描影像特征与临床指标的预测模型,用于早期评估颌面颈部间隙感染患者发生严重并发症的风险。方法回顾性纳入2022年6月—2024年6月于甘肃省人民医院口腔颌面外科收治的96例颌面颈部间隙感染患者。收... 目的构建并验证一个结合计算机断层扫描影像特征与临床指标的预测模型,用于早期评估颌面颈部间隙感染患者发生严重并发症的风险。方法回顾性纳入2022年6月—2024年6月于甘肃省人民医院口腔颌面外科收治的96例颌面颈部间隙感染患者。收集患者的影像学资料(包括由于感染累及的间隙数量、病灶体积、强化特征等)与临床指标(包括年龄、糖尿病史、C反应蛋白、白细胞计数)。比较并发症组与非并发症组患者各项指标的差异。将单因素分析中差异具有统计学意义的变量纳入多因素Logistic回归分析,筛选独立危险因素并构建预测模型。采用受试者操作特征曲线及曲线下面积评估模型的区分效能。结果并发症组患者在年龄、糖尿病患病率、C反应蛋白、白细胞计数、多间隙感染比例、感染灶体积、病灶强化程度,以及影像学上气体生成与液气平面出现的比例等方面,均显著高于非并发症组。多因素Logistic回归分析显示,年龄、合并糖尿病、C反应蛋白升高、白细胞计数升高、多间隙感染、感染体积增大,以及病灶强化是并发症发生的独立危险因素。结论整合计算机断层扫描影像特征与临床指标的预测模型,有助于早期识别颌面颈部间隙感染中易发生并发症的高危患者。 展开更多
关键词 感染 多间隙 预测模型 糖尿病 LOGISTIC回归分析 风险评估 预后
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轴流式止回阀结构参数对抗水锤能力的影响
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作者 张立强 施青甫 +1 位作者 左竣仁 金俊坤 《液压气动与密封》 2026年第3期79-91,共13页
针对轴流式止回阀止回过程中存在的水锤问题,利用Fluent动网格技术对轴流式止回阀的关阀过程进行研究,通过改进轴流式止回阀阀芯型线,阀体内流道的结构参数来提升阀门的抗水锤能力。选取轴流式止回阀不同的结构参数,利用正交试验并通过... 针对轴流式止回阀止回过程中存在的水锤问题,利用Fluent动网格技术对轴流式止回阀的关阀过程进行研究,通过改进轴流式止回阀阀芯型线,阀体内流道的结构参数来提升阀门的抗水锤能力。选取轴流式止回阀不同的结构参数,利用正交试验并通过多元线性回归找到影响轴流式止回阀抗水锤能力的主要结构参数,以其作为优化对象。利用高斯过程回归构建代理模型,再通过非支配排序算法II对主要结构参数进行多目标优化,得到Pareto前沿解,最终确定了抗水锤能力最强的结构参数:阀瓣丰满系数α_(1)为0.69613,通孔半径R为6.9 mm。相比未优化前轴流式止回阀的抗水锤能力提高了14.37%,且止回过程中止回阀的反应速度仅下降了1.13%。 展开更多
关键词 轴流式止回阀 抗水锤能力 动网格 高斯过程回归 多目标优化
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基于MSVR-MOPSO的水驱开发油藏注采优化方法研究
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作者 宋微 孟繁明 +4 位作者 李艳春 王素玲 董康兴 封兆辉 任传晓 《石油机械》 北大核心 2026年第3期43-54,共12页
针对高含水油田开发过程中面临的含水体积分数上升与产量递减矛盾,以及传统数值模拟优化计算耗时大、单输出模型难以兼顾多变量关联性等问题,提出了一种基于多输出支持向量回归(MSVR)与多目标粒子群优化(MOPSO)的注采闭环优化技术方案... 针对高含水油田开发过程中面临的含水体积分数上升与产量递减矛盾,以及传统数值模拟优化计算耗时大、单输出模型难以兼顾多变量关联性等问题,提出了一种基于多输出支持向量回归(MSVR)与多目标粒子群优化(MOPSO)的注采闭环优化技术方案。该方案利用MSVR构建包含产油量与含水体积分数的多变量同步预测代理模型,替代高耗时的数值模拟计算;构建以累计产油量最大化与综合含水体积分数最小化为双目标的优化模型,引入MOPSO算法进行全局寻优。该方法解决了复杂油藏系统快速建模与多目标协同优化的难题,克服了传统单输出模型独立建模导致的维度冗余与误差累积,实现了“增油”与“控水”冲突目标的智能决策。研究及试验结果表明:MSVR代理模型预测性能优异,经过超参数优化后,其平均绝对误差(E_(MA))从6000左右大幅降至1000左右,各关键指标决定系数(R^(2))均大于0.96,预测精度与稳定性显著优于传统SVR模型;MOPSO算法能够有效处理多目标冲突,搜索到的帕累托(Pareto)前沿清晰揭示了不同注采方案下产油量与含水体积分数的制约关系,高效获取了非支配解集。在杏十区油藏实际井组应用中,优化后的注采方案使综合含水体积分数降低了0.5823%,累计产油量增加了325.91 m^(3),验证了该方法在实际生产中的有效性。所得结论可为我国老油田二次开发提供一种可复制、高效率的智能化解决方案与技术支撑。 展开更多
关键词 高含水油田 注采优化 代理建模 多输出支持向量回归 多目标优化
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基于GPR模型的多保真气动力建模方法
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作者 罗希 黄俊 +1 位作者 唐磊 王庆凤 《空气动力学学报》 北大核心 2026年第3期22-34,共13页
通过整合不同保真度的数据,多保真气动力建模能够有效提升飞行器气动特性分析的计算效率和预测精度。为了更好处理高低保真数据之间同时存在的线性和非线性的混合复杂相关性,本文在非线性自回归高斯过程(nonlinear autoregressive Gauss... 通过整合不同保真度的数据,多保真气动力建模能够有效提升飞行器气动特性分析的计算效率和预测精度。为了更好处理高低保真数据之间同时存在的线性和非线性的混合复杂相关性,本文在非线性自回归高斯过程(nonlinear autoregressive Gaussian process,NARGP)模型的基础上,提出了一种新的多保真高斯过程回归模型(multi-fidelity Gaussian process regressive,MFGPR)。该模型通过结合线性核函数和非线性核函数,扩展了NARGP的能力,能够同时处理多保真数据中复杂的非线性关系和线性依赖性。为验证MFGPR的有效性,本文选取两类经典解析函数进行数值测试,并与Cokriging、NARGP和MFDNN三种传统多保真方法进行了对比分析。结果表明,在处理线性相关关系时,MFGPR的预测性能与CoKriging基本一致;而在非线性相关关系建模中,MFGPR相较于其他三种方法表现出更高的预测精度,同时在建模效率方面更具优势。进一步地,本文将MFGPR应用于ONERA M6机翼的压力分布预测和NACA2414翼型的阻力系数预测问题上,验证了其在气动力建模中的应用潜力和优越性能。 展开更多
关键词 多保真气动力建模 气动特性 高斯过程回归 线性核函数 建模效率
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