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基于LMDI模型的土地利用碳排放时空差异及影响因素研究——以洞庭湖区为例 被引量:2
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作者 谭洁 刘琴 +2 位作者 唐晓佩 谭雪兰 刘沛 《地域研究与开发》 CSSCI 北大核心 2024年第1期160-166,共7页
运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水... 运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水域和草地次之,耕地和林地的变化程度最小。(2)总净碳排放量呈不断上升趋势,碳排放高值区由中部转向西、东、南部,土地利用碳足迹压力指数始终大于1,以0.54的年均增幅不断上升。(3)人均GDP、单位GDP用地面积和单位土地碳排放强度是影响土地利用碳排放的主要因子,人均GDP和单位GDP用地面积分别成为促进和减缓洞庭湖区碳排放量增长的主要因素。 展开更多
关键词 土地利用 碳排放 时空演变 影响因素 lmdi模型 洞庭湖区
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基于LMDI和系统聚类的电力行业碳排放影响因素分析 被引量:2
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作者 施应玲 余欣玥 《生态经济》 北大核心 2024年第2期22-29,共8页
电力行业作为直接使用一次能源的最大部门,是落实我国碳减排目标的重点行业。为厘清电力行业碳排放的主要驱动或抑制来源,论文构建了LMDI模型,从国家及省域两个层面对2006—2020年电力行业碳排放的影响因素进行了分解。研究结果表明,从... 电力行业作为直接使用一次能源的最大部门,是落实我国碳减排目标的重点行业。为厘清电力行业碳排放的主要驱动或抑制来源,论文构建了LMDI模型,从国家及省域两个层面对2006—2020年电力行业碳排放的影响因素进行了分解。研究结果表明,从国家及省域两个层面来看,经济发展效应均为电力碳排放的主要促进因素,火电燃料转化效应和产业结构效应均为电力碳排放的抑制因素,电源结构效应、工业电耗强度效应在全国层面为电力碳排放的抑制因素,但在各省份中的影响效果及程度各有不同。论文以主要抑制因素为变量,利用系统聚类法将30个省份划分为六大区域,针对各区域影响因素的作用效果提出了因地制宜的减排政策。 展开更多
关键词 电力行业 碳排放 影响因素 lmdi模型 Q系统聚类
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基于LMDI和Tapio脱钩模型的甘肃省碳排放研究
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作者 张爱宁 李滋婷 李宗省 《西北师范大学学报(自然科学版)》 CAS 2024年第3期55-63,共9页
在定量核算2005—2021年甘肃省碳排放量和强度的基础上,预测分析基准情景、高排放情景和低排放情景3种发展情景下甘肃省碳达峰时间及路径.研究表明,甘肃省整体脱钩状态较为理想,贡献主要来源于煤炭碳排放量与经济增长长期处于弱脱钩;经... 在定量核算2005—2021年甘肃省碳排放量和强度的基础上,预测分析基准情景、高排放情景和低排放情景3种发展情景下甘肃省碳达峰时间及路径.研究表明,甘肃省整体脱钩状态较为理想,贡献主要来源于煤炭碳排放量与经济增长长期处于弱脱钩;经济增长具有增排效应,能源强度、能源结构和人口规模具有节能减排效应,尤其是能源强度.从情景预测分析看,基准情景下,甘肃省将在2035年碳排放达到峰值,2035年之后经济与碳排放处于强脱钩状态,很难在2060年之前实现碳中和;高排放情景下,将在2045达到峰值,经济与碳排放一直处于弱脱钩状态,后续实现碳达峰的难度较大;低排放情景下,2030年后经济与碳排放一直处于强脱钩状态,碳排放量下降幅度较大,在2060年之前实现碳中和较为容易. 展开更多
关键词 lmdi模型 Tapio脱钩模型 碳排放 情景设置
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江苏省经济增长与碳排放的脱钩关系研究——基于LMDI因素分解法
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作者 张敏 奚曦 《江苏科技信息》 2024年第13期21-24,共4页
文章基于2005—2020年江苏省的人口、经济发展、能源强度以及二氧化碳排放的相关数据,通过构建LMDI因素分解模型对江苏省碳排放的脱钩状态进行研究,结果表明,在“十一五”至“十三五”期间,江苏省碳排放总体处于弱脱钩状态,未达到稳定... 文章基于2005—2020年江苏省的人口、经济发展、能源强度以及二氧化碳排放的相关数据,通过构建LMDI因素分解模型对江苏省碳排放的脱钩状态进行研究,结果表明,在“十一五”至“十三五”期间,江苏省碳排放总体处于弱脱钩状态,未达到稳定的强脱钩状态;在影响碳排放的各驱动因素中,对碳排放与经济增长的脱钩状态影响最大的是能源强度效应。文章最后提出合理的降低碳排放的策略。 展开更多
关键词 碳排放脱钩 lmdi因素分解模型 Tapio脱钩指数
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基于LMDI和泰尔指数的长江经济带公共建筑碳排放变化研究
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作者 王永坤 张云辉 梁旸 《建筑节能(中英文)》 CAS 2024年第4期119-126,133,共9页
基于LMDI因素分解模型,分析了2010-2019年长江经济带碳排放综合系数、能源强度、产业结构、经济水平和城镇化率对公共建筑碳排放变动的影响,并利用泰尔指数测算了公共建筑碳排放主要影响因素的区域差异。结果表明:(1)经济水平的提高和... 基于LMDI因素分解模型,分析了2010-2019年长江经济带碳排放综合系数、能源强度、产业结构、经济水平和城镇化率对公共建筑碳排放变动的影响,并利用泰尔指数测算了公共建筑碳排放主要影响因素的区域差异。结果表明:(1)经济水平的提高和城镇化的发展是促进公共建筑碳排放增长的主要因素,而产业机构的调整和能源强度的降低则抑制了碳排放的增加。(2)基于能源强度和经济水平的碳排放泰尔指数均表明区域内差异是造成该经济带公共建筑碳排放不平衡的主要原因,各区域阶梯效应削弱,区域内部呈现分化发展的局面。(3)政府应重点关注区域内部互联,建立以经济水平碳排放为约束指标的碳减排协同治理机制,实现长江经济带公共建筑业的协调发展。 展开更多
关键词 公共建筑碳排放 lmdi因素分解 泰尔指数 长江经济带
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Development of a model based on the age-adjusted Charlson comorbidity index to predict survival for resected perihilar cholangiocarcinoma 被引量:6
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作者 Yu Pan Zhi-Peng Liu +15 位作者 Hai-Su Dai Wei-Yue Chen Ying Luo Yu-Zhu Wang Shu-Yang Gao Zi-Ran Wang Jin-Ling Dong Yun-Hua Liu Xian-Yu Yin Xing-Chao Liu Hai-Ning Fan Jie Bai Yan Jiang Jun-Jie Cheng Yan-Qi Zhang Zhi-Yu Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第6期1036-1050,共15页
BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of p... BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of patients with multiple malignancies was recently reported.However,pCCA is one of the most surgically difficult gastrointestinal tumors with the poorest prognosis,and the value of the ACCI for the prognosis of pCCA patients after curative resection is unclear.AIM To evaluate the prognostic value of the ACCI and to design an online clinical model for pCCA patients.METHODS Consecutive pCCA patients after curative resection between 2010 and 2019 were enrolled from a multicenter database.The patients were randomly assigned 3:1 to training and validation cohorts.In the training and validation cohorts,all patients were divided into low-,moderate-,and high-ACCI groups.Kaplan-Meier curves were used to determine the impact of the ACCI on overall survival(OS)for pCCA patients,and multivariate Cox regression analysis was used to determine the independent risk factors affecting OS.An online clinical model based on the ACCI was developed and validated.The concordance index(C-index),calibration curve,and receiver operating characteristic(ROC)curve were used to evaluate the predictive performance and fit of this model.RESULTS A total of 325 patients were included.There were 244 patients in the training cohort and 81 patients in the validation cohort.In the training cohort,116,91 and 37 patients were classified into the low-,moderate-and high-ACCI groups.The Kaplan-Meier curves showed that patients in the moderate-and high-ACCI groups had worse survival rates than those in the low-ACCI group.Multivariable analysis revealed that moderate and high ACCI scores were independently associated with OS in pCCA patients after curative resection.In addition,an online clinical model was developed that had ideal C-indexes of 0.725 and 0.675 for predicting OS in the training and validation cohorts.The calibration curve and ROC curve indicated that the model had a good fit and prediction performance.CONCLUSION A high ACCI score may predict poor long-term survival in pCCA patients after curative resection.High-risk patients screened by the ACCI-based model should be given more clinical attention in terms of the management of comorbidities and postoperative follow-up. 展开更多
关键词 Perihilar cholangiocarcinoma Age-adjusted Charlson comorbidity index RESECTION SURVIVAL model PROGNOSIS
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基于脱钩指数和LMDI的第三产业用水发展研究 被引量:1
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作者 姚园 李海红 +2 位作者 李溦 赵勇 王丽珍 《水资源与水工程学报》 CSCD 北大核心 2024年第1期71-81,共11页
第三产业在我国国民经济中占有重要地位,识别用水与产业发展关系并合理控制用水发展对于未来管控用水增长具有重要意义。基于Tapio脱钩模型和LMDI分解模型,分析我国内地31个省级行政区2000—2020年第三产业经济与用水的脱钩时空演化及... 第三产业在我国国民经济中占有重要地位,识别用水与产业发展关系并合理控制用水发展对于未来管控用水增长具有重要意义。基于Tapio脱钩模型和LMDI分解模型,分析我国内地31个省级行政区2000—2020年第三产业经济与用水的脱钩时空演化及其驱动效应,并基于分析结果对未来第三产业的用水目标和节水压力开展情景分析。结果表明:在时间尺度上,目前我国第三产业实现了稳定弱脱钩,经济年均增长率为12.2%,远高于用水年均变化率3.6%,2012年后全国强脱钩范围扩大;在空间尺度上,不同地区第三产业脱钩状态存在差异,东部和西部地区脱钩状态较好,实现良好脱钩的省市区占比可达到70%~80%;驱动因素方面,第三产业脱钩的负向驱动效应主要是经济规模,正向驱动效应是节水能力,东部和西部地区节水能力效应贡献率达到56.8%、52.6%,中部地区贡献率仅为38.3%,驱动因素作用程度存在差异从而影响脱钩;未来为实现我国第三产业协调可持续发展,在发展经济时将面临一定节水压力,其增长过程具有规模累积效应与时间累积效应,在经济高速发展至2050年时将达到8.8%。在未来长期规划下更应重视强化节水能力,以促进第三产业良好脱钩,从而实现协调可持续发展。 展开更多
关键词 第三产业用水 经济发展 脱钩模型 lmdi分解 用水目标
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Novel Hybrid X GBoost Model to Forecast Soil Shear Strength Based on Some Soil Index Tests 被引量:1
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作者 Ehsan Momeni Biao He +1 位作者 Yasin Abdi Danial Jahed Armaghani 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2527-2550,共24页
When building geotechnical constructions like retaining walls and dams is of interest,one of the most important factors to consider is the soil’s shear strength parameters.This study makes an effort to propose a nove... When building geotechnical constructions like retaining walls and dams is of interest,one of the most important factors to consider is the soil’s shear strength parameters.This study makes an effort to propose a novel predictive model of shear strength.The study implements an extreme gradient boosting(XGBoost)technique coupled with a powerful optimization algorithm,the salp swarm algorithm(SSA),to predict the shear strength of various soils.To do this,a database consisting of 152 sets of data is prepared where the shear strength(τ)of the soil is considered as the model output and some soil index tests(e.g.,dry unit weight,water content,and plasticity index)are set as model inputs.Themodel is designed and tuned using both effective parameters of XGBoost and SSA,and themost accuratemodel is introduced in this study.Thepredictionperformanceof theSSA-XGBoostmodel is assessedbased on the coefficient of determination(R2)and variance account for(VAF).Overall,the obtained values of R^(2) and VAF(0.977 and 0.849)and(97.714%and 84.936%)for training and testing sets,respectively,confirm the workability of the developed model in forecasting the soil shear strength.To investigate the model generalization,the prediction performance of the model is tested for another 30 sets of data(validation data).The validation results(e.g.,R^(2) of 0.805)suggest the workability of the proposed model.Overall,findings suggest that when the shear strength of the soil cannot be determined directly,the proposed hybrid XGBoost-SSA model can be utilized to assess this parameter. 展开更多
关键词 Predictive model salp swarm algorithm soil index tests soil shear strength XGBoost
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Combining RUSLE model and the vegetation health index to unravel the relationship between soil erosion and droughts in southeastern Tunisia 被引量:1
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作者 Olfa TERWAYET BAYOULI ZHANG Wanchang Houssem TERWAYET BAYOULI 《Journal of Arid Land》 SCIE CSCD 2023年第11期1269-1289,共21页
Droughts and soil erosion are among the most prominent climatic driven hazards in drylands,leading to detrimental environmental impacts,such as degraded lands,deteriorated ecosystem services and biodiversity,and incre... Droughts and soil erosion are among the most prominent climatic driven hazards in drylands,leading to detrimental environmental impacts,such as degraded lands,deteriorated ecosystem services and biodiversity,and increased greenhouse gas emissions.In response to the current lack of studies combining drought conditions and soil erosion processes,in this study,we developed a comprehensive Geographic Information System(GIS)-based approach to assess soil erosion and droughts,thereby revealing the relationship between soil erosion and droughts under an arid climate.The vegetation condition index(VCI)and temperature condition index(TCI)derived respectively from the enhanced vegetation index(EVI)MOD13A2 and land surface temperature(LST)MOD11A2 products were combined to generate the vegetation health index(VHI).The VHI has been conceived as an efficient tool to monitor droughts in the Negueb watershed,southeastern Tunisia.The revised universal soil loss equation(RUSLE)model was applied to quantitatively estimate soil erosion.The relationship between soil erosion and droughts was investigated through Pearson correlation.Results exhibited that the Negueb watershed experienced recurrent mild to extreme drought during 2000–2016.The average soil erosion rate was determined to be 1.8 t/(hm2•a).The mountainous western part of the watershed was the most vulnerable not only to soil erosion but also to droughts.The slope length and steepness factor was shown to be the most significant controlling parameter driving soil erosion.The relationship between droughts and soil erosion had a positive correlation(r=0.3);however,the correlation was highly varied spatially across the watershed.Drought was linked to soil erosion in the Negueb watershed.The current study provides insight for natural disaster risk assessment,land managers,and stake-holders to apply appropriate management measures to promote sustainable development goals in fragile environments. 展开更多
关键词 DROUGHTS soil erosion vegetation health index(VHI) revised universal soil loss equation(RUSLE)model southeastern Tunisia
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基于LMDI模型的湖北省农业水足迹时空分布与驱动力研究 被引量:1
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作者 杨润丁 杨冬民 《中国水土保持科学》 CSCD 北大核心 2024年第1期106-113,共8页
结合水足迹理论和传统农业用水核算方法,分析2005—2020年湖北省各市州农业水足迹时空演变特征,并利用LMDI模型对农业水足迹变化量进行驱动力因素分解。结果表明:1)湖北省农业水足迹呈现先上升再下降的波动趋势;湖北省各市州农业水足迹... 结合水足迹理论和传统农业用水核算方法,分析2005—2020年湖北省各市州农业水足迹时空演变特征,并利用LMDI模型对农业水足迹变化量进行驱动力因素分解。结果表明:1)湖北省农业水足迹呈现先上升再下降的波动趋势;湖北省各市州农业水足迹存在明显的时空分布差异,这是自然因素和经济因素共同作用的结果。2)各驱动力对湖北省农业水足迹变化的影响程度为经济效应>技术效应>人口效应,经济效应对农业水足迹变化量的贡献值,达53.72%,技术效应和人口效应的贡献值分别为32.86%和13.42%;其中,经济效应对农业水足迹起正向驱动作用,技术效应和人口效应对农业水足迹起到反向驱动的作用。研究结论拓展了长江流域农业水足迹及驱动力分析,同时对于提高农业可持续发展、增加农业用水效率有指导意义。 展开更多
关键词 农业水足迹 时空分布 lmdi模型 驱动力
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Extreme gradient boosting algorithm based urban daily traffic index prediction model:a case study of Beijing,China 被引量:1
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作者 Jiancheng Weng Kai Feng +2 位作者 Yu Fu Jingjing Wang Lizeng Mao 《Digital Transportation and Safety》 2023年第3期220-228,共9页
The exhaust emissions and frequent traffic incidents caused by traffic congestion have affected the operation and development of urban transport systems.Monitoring and accurately forecasting urban traffic operation is... The exhaust emissions and frequent traffic incidents caused by traffic congestion have affected the operation and development of urban transport systems.Monitoring and accurately forecasting urban traffic operation is a critical task to formulate pertinent strategies to alleviate traffic congestion.Compared with traditional short-time traffic prediction,this study proposes a machine learning algorithm-based traffic forecasting model for daily-level peak hour traffic operation status prediction by using abundant historical data of urban traffic performance index(TPI).The study also constructed a multi-dimensional influencing factor set to further investigate the relationship between different factors on the quality of road network operation,including day of week,time period,public holiday,car usage restriction policy,special events,etc.Based on long-term historical TPI data,this research proposed a daily dimensional road network TPI prediction model by using an extreme gradient boosting algorithm(XGBoost).The model validation results show that the model prediction accuracy can reach higher than 90%.Compared with other prediction models,including Bayesian Ridge,Linear Regression,ElatsicNet,SVR,the XGBoost model has a better performance,and proves its superiority in large high-dimensional data sets.The daily dimensional prediction model proposed in this paper has an important application value for predicting traffic status and improving the operation quality of urban road networks. 展开更多
关键词 Traffic prediction Traffic performance index(TPI) Influencing factor XGBOOST Machine learning model
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Predictive model using four ferroptosis-related genes accurately predicts gastric cancer prognosis 被引量:1
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作者 Li Wang Wei-Hua Gong 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2018-2037,共20页
BACKGROUND Gastric cancer(GC)is a common malignancy of the digestive system.According to global 2018 cancer data,GC has the fifth-highest incidence and the thirdhighest fatality rate among malignant tumors.More than 6... BACKGROUND Gastric cancer(GC)is a common malignancy of the digestive system.According to global 2018 cancer data,GC has the fifth-highest incidence and the thirdhighest fatality rate among malignant tumors.More than 60%of GC are linked to infection with Helicobacter pylori(H.pylori),a gram-negative,active,microaerophilic,and helical bacterium.This parasite induces GC by producing toxic factors,such as cytotoxin-related gene A,vacuolar cytotoxin A,and outer membrane proteins.Ferroptosis,or iron-dependent programmed cell death,has been linked to GC,although there has been little research on the link between H.pylori infection-related GC and ferroptosis.AIM To identify coregulated differentially expressed genes among ferroptosis-related genes(FRGs)in GC patients and develop a ferroptosis-related prognostic model with discrimination ability.METHODS Gene expression profiles of GC patients and those with H.pylori-associated GC were obtained from The Cancer Genome Atlas and Gene Expression Omnibus(GEO)databases.The FRGs were acquired from the FerrDb database.A ferroptosis-related gene prognostic index(FRGPI)was created using least absolute shrinkage and selection operator–Cox regression.The predictive ability of the FRGPI was validated in the GEO cohort.Finally,we verified the expression of the hub genes and the activity of the ferroptosis inducer FIN56 in GC cell lines and tissues.RESULTS Four hub genes were identified(NOX4,MTCH1,GABARAPL2,and SLC2A3)and shown to accurately predict GC and H.pylori-associated GC.The FRGPI based on the hub genes could independently predict GC patient survival;GC patients in the high-risk group had considerably worse overall survival than did those in the low-risk group.The FRGPI was a significant predictor of GC prognosis and was strongly correlated with disease progression.Moreover,the gene expression levels of common immune checkpoint proteins dramatically increased in the highrisk subgroup of the FRGPI cohort.The hub genes were also confirmed to be highly overexpressed in GC cell lines and tissues and were found to be primarily localized at the cell membrane.The ferroptosis inducer FIN56 inhibited GC cell proliferation in a dose-dependent manner.CONCLUSION In this study,we developed a predictive model based on four FRGs that can accurately predict the prognosis of GC patients and the efficacy of immunotherapy in this population. 展开更多
关键词 Ferroptosis Gastric cancer Helicobacter pylori infection Immune checkpoint protein Prognostic model Ferroptosis-related gene prognostic index
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中国钢铁产业碳排放脱钩弹性及驱动因素——基于Tapio脱钩模型与LMDI分析 被引量:1
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作者 李汝晴 《绿色矿冶》 2024年第3期1-8,14,共9页
新发展阶段,明晰钢铁碳排放与产业增长的关联,厘清钢铁碳减排路径,将助力实现钢铁产业高质量发展,推动钢铁领域“双碳”进程。基于2000—2019年中国钢铁碳排放测算数据,运用Tapio脱钩模型分析中国钢铁产业碳排放与产业增长的关系,采用... 新发展阶段,明晰钢铁碳排放与产业增长的关联,厘清钢铁碳减排路径,将助力实现钢铁产业高质量发展,推动钢铁领域“双碳”进程。基于2000—2019年中国钢铁碳排放测算数据,运用Tapio脱钩模型分析中国钢铁产业碳排放与产业增长的关系,采用对数平均迪氏指数(LMDI)对碳排放驱动因素进行分解。研究表明,2000—2019年中国钢铁产业碳排放与产业增长的脱钩状态较为稳定,基本上呈现弱脱钩状态。生产规模效应和资源效率效应是碳排放量增加的主要驱动因素,能源结构强度效应和能源消耗强度效应对碳排放具有抑制作用。建议从大幅增加钢铁行业科研投入、调整钢铁行业能源结构、创新工艺流程、制定科学合理的发展规模等方面开展钢铁产业碳减排工作,助力低碳钢铁产业高质量发展。 展开更多
关键词 钢铁产业 碳排放 Tapio脱钩模型 lmdi模型 驱动因素
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Machine Learning for Hybrid Line Stability Ranking Index in Polynomial Load Modeling under Contingency Conditions
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作者 P.Venkatesh N.Visali 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期1001-1012,共12页
In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression f... In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression for fast predicting the severity of the line and clustering by incorporating machine learning aspects.The polynomial load modelling or ZIP(constant impedances(Z),Constant Current(I)and Constant active power(P))is developed in the IEEE-14 and Indian 118 bus systems considered for analysis of power system security.The process of finding the severity of the line using a Hybrid Line Stability Ranking Index(HLSRI)is used for assisting the concepts of machine learning with J48 algorithm,infers the superior affected lines by adopting the IEEE standards in concern to be compensated in maintaining the power system stability.The simulation is performed in the WEKA environment and deals with the supervisor learning in order based on severity to ensure the safety of power system.The Unified Power Flow Controller(UPFC),facts devices for the purpose of compensating the losses by maintaining the voltage characteristics.The finite element analysis findings are compared with the existing procedures and numerical equations for authentications. 展开更多
关键词 CONTINGENCY hybrid line stability ranking index(HLSRI) machine learning(ML) unified power flow controller(UPFC) ZIP load modelling
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应用LMDI模型的江西省交通运输业碳排放驱动力分析 被引量:2
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作者 刘安 习明星 +1 位作者 邵志超 李雪洁 《华侨大学学报(自然科学版)》 CAS 2024年第2期276-282,共7页
通过统计分析江西省2011-2020年公路运输、水路运输、铁路运输和民航运输总的能源消耗数据,确定了江西省交通运输业二氧化碳排放的变化趋势。利用对数平均权重(LMDI)法,分析了模式分担、能源结构、规模效应、能源强度、经济效应对江西... 通过统计分析江西省2011-2020年公路运输、水路运输、铁路运输和民航运输总的能源消耗数据,确定了江西省交通运输业二氧化碳排放的变化趋势。利用对数平均权重(LMDI)法,分析了模式分担、能源结构、规模效应、能源强度、经济效应对江西省交通运输部门碳排放变化产生的不同影响。研究结果表明:2011-2020年,江西省能源使用最多的是汽油和柴油;公路运输部门是江西省交通运输部门碳排放最多的部门;对碳排放的增长起推动作用的是模式分担与经济效应,起抑制作用的是能源结构与规模效应,而能源强度波动较大。 展开更多
关键词 碳排放 交通运输业 驱动力因素 对数平均权重(lmdi)法 公路运输 江西省
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基于LMDI模型的黄河中游城市群水土资源利用影响因素分析 被引量:1
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作者 鲁仕宝 王少华 +2 位作者 裴亮 邓伟升 唐鸿磊 《水土保持学报》 CSCD 北大核心 2024年第1期140-148,共9页
[目的]水土资源是城市发展的重要生产要素,是探索黄河中游城市群水土资源利用过程中的关键因素,对科学促进黄河中游城市群经济快速发展具有重要意义。[方法]以黄河中游三大城市群为例,通过运用LMDI加法模型对2010—2019年黄河中游三大... [目的]水土资源是城市发展的重要生产要素,是探索黄河中游城市群水土资源利用过程中的关键因素,对科学促进黄河中游城市群经济快速发展具有重要意义。[方法]以黄河中游三大城市群为例,通过运用LMDI加法模型对2010—2019年黄河中游三大城市群分别构建影响水资源消耗量变化及城市建设用地数量变化的因素分解模型,计算并比较不同驱动因素的效应值。[结果](1)水资源利用效率提高和产业结构的优化能够抑制水资源消耗量的增加,而经济规模和人口规模扩大则促进其增加。(2)产业规模、经济规模及人口规模扩大对建设用地扩张存在推动作用,而城市建设用地消耗强度对建设用地扩张具有抑制作用。(3)对于水资源利用量变化,黄河中游不同城市之间产业结构优化水平存在较大差距;对于城市建设用地变化,三大城市群总效应值比较结果为关中平原城市群>中原城市群>晋中城市群。[结论]基于区域差异和时间差异角度探讨黄河中游城市群水土资源利用的影响因素,有助于丰富水土资源可持续利用的相关研究,为黄河中游城市群的可持续发展提供理论指导。 展开更多
关键词 lmdi模型 黄河中游城市群 水资源 土地资源
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Spatio-temporal evolution analysis of landscape pattern and habitat quality in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 based on InVEST model
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作者 ZHENG Guoqiang Li Cunxiu +3 位作者 LI Runjie LUO Jing FAN Chunxia ZHU Hailing 《Journal of Arid Land》 SCIE CSCD 2024年第9期1183-1196,共14页
Habitat quality is an important indicator for evaluating the quality of ecosystem.The Qinghai Province section of the Yellow River Basin plays an important role in the ecological protection of the upper reaches of the... Habitat quality is an important indicator for evaluating the quality of ecosystem.The Qinghai Province section of the Yellow River Basin plays an important role in the ecological protection of the upper reaches of the Yellow River Basin.To comprehensively analysis the alterations of habitat quality in the Qinghai Province section of the Yellow River Basin,this study utilized the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to calculate the habitat quality index and analyze the spatio-temporal variation characteristics of habitat quality in the study area from 2000 to 2022,and calculated seven landscape pattern indices(number of patches,patch density,largest patch index(LPI),landscape shape index(LSI),contagion index(CONTAG),Shannon diversity index,and Shannon evenness index)to research the variation of landscape pattern in the study area.The results showed that the number of patches,patch density,LPI,LSI,Shannon diversity index,and Shannon evenness index increased from 2000 to 2022,while the CONTAG decreased,indicating that the landscape pattern in the Qinghai Province section of the Yellow River Basin changed in the direction of distribution fragmentation,shape complexity,and heterogeneity.The average value of the habitat quality index in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 was 0.90.Based on the value of habitat quality index,we divided the level of habitat quality into five categories:lower(0.00-0.20),low(0.20-0.40),moderate(0.40-0.60),high(0.60-0.80),and higher(0.80-1.00).Most areas were at the higher habitat quality level.The lower habitat quality patches were mainly distributed in Longyang Gorge and Yellow River-Huangshui River Valley.From 2000 to 2022,the habitat quality in most areas was stable;the increase areas were mainly distributed in Guinan County,while the decrease areas were mainly distributed in Xining City,Maqen County,Xinghai County,Qumarleb County,and Darlag County.To show the extent of habitat quality variation,we calculated Sen index.The results showed that the higher habitat quality area had a decrease trending,while other categories had an increasing tendency,and the decreasing was faster than increasing.The research results provide scientific guidance for promoting ecological protection and high-quality development in the Qinghai Province section of the Yellow River Basin. 展开更多
关键词 InVEST model landscape pattern index habitat quality largest patch index landscape shape index Shannon evenness index
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基于LMDI模型的辽宁省农业碳排放影响因素研究
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作者 刘波涛 曲睿婷 +3 位作者 乔林 郭美洁 郭紫璇 王体朋 《农业工程》 2024年第10期58-63,共6页
在“十四五”规划指导下,辽宁省加快推进农业农村现代化,推动辽宁省由农业大省向农业强省跨越,需明确辽宁省农业碳排放影响因素,寻找农业碳减排侧重点。基于2012—2021年辽宁省农业碳排放历史数据,通过LMDI模型因素分解法识别农业碳排... 在“十四五”规划指导下,辽宁省加快推进农业农村现代化,推动辽宁省由农业大省向农业强省跨越,需明确辽宁省农业碳排放影响因素,寻找农业碳减排侧重点。基于2012—2021年辽宁省农业碳排放历史数据,通过LMDI模型因素分解法识别农业碳排放主要驱动因素,并利用STIRPAT模型定向定量分析各变量数量关系。通过LMDI模型因素分解方法将辽宁省农业碳排放分解为农业碳排放系数、能源强度、农业产业结构、农业经济发展水平及人口规模,其中农业碳排放系数、能源强度和人口规模对农业碳排放存在负向影响,农业产业结构和农业经济发展水平存在正向影响;STIRPAT模型显示,当其他因素保持不变时,农业碳排放系数、能源强度、农业产业结构、农业经济发展水平和人口规模分别变化1%,辽宁省农业碳排放分别变化0.4997%、0.0140%、-0.0735%、-0.0241%和0.2418%,并且模型分析与LMDI模型因素分解呈现相同结果。在“双碳”目标背景下,建议控制化肥施用量、改善农村人口生活环境、稳定保持农村经济持续增长及促进辽宁省农业有效碳减排。 展开更多
关键词 农业碳排放 lmdi模型 驱动因素 节能减排
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Developments in the study of Chinese herbal medicine's assessment index and action mechanism for diabetes mellitus
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作者 Xin-Yue Liu Han-Wen Zheng +3 位作者 Feng-Zhong Wang Tul-Wahab Atia Bei Fan Qiong Wang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第4期433-443,共11页
In traditional Chinese medicine(TCM),based on various pathogenic symptoms and the‘golden chamber’medical text,Huangdi Neijing,diabetes mellitus falls under the category‘collateral disease’.TCM,with its wealth of e... In traditional Chinese medicine(TCM),based on various pathogenic symptoms and the‘golden chamber’medical text,Huangdi Neijing,diabetes mellitus falls under the category‘collateral disease’.TCM,with its wealth of experience,has been treating diabetes for over two millennia.Different antidiabetic Chinese herbal medicines re-duce blood sugar,with their effective ingredients exerting unique advantages.As well as a glucose lowering effect,TCM also regulates bodily functions to prevent diabetes associated complications,with reduced side effects compared to western synthetic drugs.Chinese herbal medicine is usually composed of polysaccharides,saponins,al-kaloids,flavonoids,and terpenoids.These active ingredients reduce blood sugar via various mechanism of actions that include boosting endogenous insulin secretion,enhancing insulin sensitivity and adjusting key enzyme activity and scavenging free radicals.These actions regulate glycolipid metabolism in the body,eventually achiev-ing the goal of normalizing blood glucose.Using different animal models,a number of molecular markers are available for the detection of diabetes induction and the molecular pathology of the disease is becoming clearer.Nonetheless,there is a dearth of scientific data about the pharmacology,dose-effect relationship,and structure-activity relationship of TCM and its constituents.Further research into the efficacy,toxicity and mode of action of TCM,using different metabolic and molecular markers,is key to developing novel TCM antidiabetic formulations. 展开更多
关键词 animal model Chinese herbal medicine diabetes mellitus evaluation index mechanism of action
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Developing and validating a predictive model of delivering large-forgestational-age infants among women with gestational diabetes mellitus
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作者 Yi-Tian Zhu Lan-Lan Xiang +3 位作者 Ya-Jun Chen Tian-Ying Zhong Jun-Jun Wang Yu Zeng 《World Journal of Diabetes》 SCIE 2024年第6期1242-1253,共12页
BACKGROUND The birth of large-for-gestational-age(LGA)infants is associated with many shortterm adverse pregnancy outcomes.It has been observed that the proportion of LGA infants born to pregnant women with gestationa... BACKGROUND The birth of large-for-gestational-age(LGA)infants is associated with many shortterm adverse pregnancy outcomes.It has been observed that the proportion of LGA infants born to pregnant women with gestational diabetes mellitus(GDM)is significantly higher than that born to healthy pregnant women.However,traditional methods for the diagnosis of LGA have limitations.Therefore,this study aims to establish a predictive model that can effectively identify women with GDM who are at risk of delivering LGA infants.AIM To develop and validate a nomogram prediction model of delivering LGA infants among pregnant women with GDM,and provide strategies for the effective prevention and timely intervention of LGA.METHODS The multivariable prediction model was developed by carrying out the following steps.First,the variables that were associated with LGA risk in pregnant women with GDM were screened by univariate analyses,for which the P value was<0.10.Subsequently,Least Absolute Shrinkage and Selection Operator regression was fit using ten cross-validations,and the optimal combination factors were se-lected by choosing lambda 1se as the criterion.The final predictors were deter-mined by multiple backward stepwise logistic regression analysis,in which only the independent variables were associated with LGA risk,with a P value<0.05.Finally,a risk prediction model was established and subsequently evaluated by using area under the receiver operating characteristic curve,calibration curve and decision curve analyses.RESULTS After using a multistep screening method,we establish a predictive model.Several risk factors for delivering an LGA infant were identified(P<0.01),including weight gain during pregnancy,parity,triglyceride-glucose index,free tetraiodothyronine level,abdominal circumference,alanine transaminase-aspartate aminotransferase ratio and weight at 24 gestational weeks.The nomogram’s prediction ability was supported by the area under the curve(0.703,0.709,and 0.699 for the training cohort,validation cohort,and test cohort,respectively).The calibration curves of the three cohorts displayed good agreement.The decision curve showed that the use of the 10%-60%threshold for identifying pregnant women with GDM who are at risk of delivering an LGA infant would result in a positive net benefit.CONCLUSION Our nomogram incorporated easily accessible risk factors,facilitating individualized prediction of pregnant women with GDM who are likely to deliver an LGA infant. 展开更多
关键词 Large-for-gestational-age Gestational diabetes mellitus Predictive model NOMOGRAM Triglyceride-glucose index
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