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基于SBM-Undesirable模型的重庆市公立综合医院运行效率评价 被引量:1
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作者 程兆辉 郑艳 +1 位作者 王宇 贺知菲 《卫生软科学》 2025年第3期25-30,共6页
[目的]分析重庆市公立综合医院运行效率现状并对二级、三级医院作对比分析,为提升医院运行效率提供参考。[方法]收集2016-2023年78家样本医院运行数据,采用描述性统计方法分析重点运行指标基本情况,采用SBM-Undesirable模型和Malmquist-... [目的]分析重庆市公立综合医院运行效率现状并对二级、三级医院作对比分析,为提升医院运行效率提供参考。[方法]收集2016-2023年78家样本医院运行数据,采用描述性统计方法分析重点运行指标基本情况,采用SBM-Undesirable模型和Malmquist-Luenberger生产率指数分析医院静态、动态效率和变化趋势。[结果]医院运行效率呈波动变化,2016-2019年为上升期,2020-2021为下降期,2022-2023为回升期,受疫情影响明显;综合效率值最高为2019年(0.832),最低为2016年(0.789),效率水平整体不高;三级医院综合效率和纯技术效率总体优于二级医院,二级医院规模效率总体优于三级医院;生产率指数为0.987,其中技术效率变动指数为1.014,技术变动指数为0.973。[结论]重庆市公立医院运行效率有待提高且受疫情影响明显,医院技术与创新方面的退步是生产率退步的主要原因。 展开更多
关键词 公立医院 运行效率 sbm-undesirable模型 数据包络分析 重庆
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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Do Higher Horizontal Resolution Models Perform Better?
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作者 Shoji KUSUNOKI 《Advances in Atmospheric Sciences》 2026年第1期259-262,共4页
Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(... Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(2025)].In relation to seasonal forecasting and climate projection in the East Asian summer monsoon season,proper simulation of the seasonal migration of rain bands by models is a challenging and limiting factor[section 7.1 in Wang et al.(2025)]. 展开更多
关键词 enhancing model resolution refinement data assimilation systems section climate model climate projection higher horizontal resolution seasonal forecasting simulation seasonal migration rain bands model resolution
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An Optimized Customer Churn Prediction Approach Based on Regularized Bidirectional Long Short-Term Memory Model
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作者 Adel Saad Assiri 《Computers, Materials & Continua》 2026年第1期1783-1803,共21页
Customer churn is the rate at which customers discontinue doing business with a company over a given time period.It is an essential measure for businesses to monitor high churn rates,as they often indicate underlying ... Customer churn is the rate at which customers discontinue doing business with a company over a given time period.It is an essential measure for businesses to monitor high churn rates,as they often indicate underlying issues with services,products,or customer experience,resulting in considerable income loss.Prediction of customer churn is a crucial task aimed at retaining customers and maintaining revenue growth.Traditional machine learning(ML)models often struggle to capture complex temporal dependencies in client behavior data.To address this,an optimized deep learning(DL)approach using a Regularized Bidirectional Long Short-Term Memory(RBiLSTM)model is proposed to mitigate overfitting and improve generalization error.The model integrates dropout,L2-regularization,and early stopping to enhance predictive accuracy while preventing over-reliance on specific patterns.Moreover,this study investigates the effect of optimization techniques on boosting the training efficiency of the developed model.Experimental results on a recent public customer churn dataset demonstrate that the trained model outperforms the traditional ML models and some other DL models,such as Long Short-Term Memory(LSTM)and Deep Neural Network(DNN),in churn prediction performance and stability.The proposed approach achieves 96.1%accuracy,compared with LSTM and DNN,which attain 94.5%and 94.1%accuracy,respectively.These results confirm that the proposed approach can be used as a valuable tool for businesses to identify at-risk consumers proactively and implement targeted retention strategies. 展开更多
关键词 Customer churn prediction deep learning RBiLSTM DROPOUT baseline models
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When Large Language Models and Machine Learning Meet Multi-Criteria Decision Making: Fully Integrated Approach for Social Media Moderation
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作者 Noreen Fuentes Janeth Ugang +4 位作者 Narcisan Galamiton Suzette Bacus Samantha Shane Evangelista Fatima Maturan Lanndon Ocampo 《Computers, Materials & Continua》 2026年第1期2137-2162,共26页
This study demonstrates a novel integration of large language models,machine learning,and multicriteria decision-making to investigate self-moderation in small online communities,a topic under-explored compared to use... This study demonstrates a novel integration of large language models,machine learning,and multicriteria decision-making to investigate self-moderation in small online communities,a topic under-explored compared to user behavior and platform-driven moderation on social media.The proposed methodological framework(1)utilizes large language models for social media post analysis and categorization,(2)employs k-means clustering for content characterization,and(3)incorporates the TODIM(Tomada de Decisão Interativa Multicritério)method to determine moderation strategies based on expert judgments.In general,the fully integrated framework leverages the strengths of these intelligent systems in a more systematic evaluation of large-scale decision problems.When applied in social media moderation,this approach promotes nuanced and context-sensitive self-moderation by taking into account factors such as cultural background and geographic location.The application of this framework is demonstrated within Facebook groups.Eight distinct content clusters encompassing safety,harassment,diversity,and misinformation are identified.Analysis revealed a preference for content removal across all clusters,suggesting a cautious approach towards potentially harmful content.However,the framework also highlights the use of other moderation actions,like account suspension,depending on the content category.These findings contribute to the growing body of research on self-moderation and offer valuable insights for creating safer and more inclusive online spaces within smaller communities. 展开更多
关键词 Self-moderation user-generated content k-means clustering TODIM large language models
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A Boundary Element Reconstruction (BER) Model for Moving Morphable Component Topology Optimization
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作者 Zhao Li Hongyu Xu +2 位作者 Shuai Zhang Jintao Cui Xiaofeng Liu 《Computers, Materials & Continua》 2026年第1期2213-2230,共18页
The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is m... The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is mainly used for finite element analysis at present,and the effectiveness of the surrogate material model has been fully confirmed.However,there are some accuracy problems when dealing with boundary elements using the surrogate material model,which will affect the topology optimization results.In this study,a boundary element reconstruction(BER)model is proposed based on the surrogate material model under the MMC topology optimization framework to improve the accuracy of topology optimization.The proposed BER model can reconstruct the boundary elements by refining the local meshes and obtaining new nodes in boundary elements.Then the density of boundary elements is recalculated using the new node information,which is more accurate than the original model.Based on the new density of boundary elements,the material properties and volume information of the boundary elements are updated.Compared with other finite element analysis methods,the BER model is simple and feasible and can improve computational accuracy.Finally,the effectiveness and superiority of the proposed method are verified by comparing it with the optimization results of the original surrogate material model through several numerical examples. 展开更多
关键词 Topology optimization MMC method boundary element reconstruction surrogate material model local mesh
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Face-Pedestrian Joint Feature Modeling with Cross-Category Dynamic Matching for Occlusion-Robust Multi-Object Tracking
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作者 Qin Hu Hongshan Kong 《Computers, Materials & Continua》 2026年第1期870-900,共31页
To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework ba... To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework based on face-pedestrian joint feature modeling.By constructing a joint tracking model centered on“intra-class independent tracking+cross-category dynamic binding”,designing a multi-modal matching metric with spatio-temporal and appearance constraints,and innovatively introducing a cross-category feature mutual verification mechanism and a dual matching strategy,this work effectively resolves performance degradation in traditional single-category tracking methods caused by short-term occlusion,cross-camera tracking,and crowded environments.Experiments on the Chokepoint_Face_Pedestrian_Track test set demonstrate that in complex scenes,the proposed method improves Face-Pedestrian Matching F1 area under the curve(F1 AUC)by approximately 4 to 43 percentage points compared to several traditional methods.The joint tracking model achieves overall performance metrics of IDF1:85.1825%and MOTA:86.5956%,representing improvements of 0.91 and 0.06 percentage points,respectively,over the baseline model.Ablation studies confirm the effectiveness of key modules such as the Intersection over Area(IoA)/Intersection over Union(IoU)joint metric and dynamic threshold adjustment,validating the significant role of the cross-category identity matching mechanism in enhancing tracking stability.Our_model shows a 16.7%frame per second(FPS)drop vs.fairness of detection and re-identification in multiple object tracking(FairMOT),with its cross-category binding module adding aboute 10%overhead,yet maintains near-real-time performance for essential face-pedestrian tracking at small resolutions. 展开更多
关键词 Cross-category dynamic binding joint feature modeling face-pedestrian association multi object tracking occlusion robustness
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Motion In-Betweening via Frequency-Domain Diffusion Model
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作者 Qiang Zhang Shuo Feng +2 位作者 Shanxiong Chen Teng Wan Ying Qi 《Computers, Materials & Continua》 2026年第1期275-296,共22页
Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frame... Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frames remains a fundamental yet unresolved challenge.Existing methods typically rely on dense keyframe inputs or complex prior structures,making it difficult to balance motion quality and plausibility under conditions such as sparse constraints,long-term dependencies,and diverse motion styles.To address this,we propose a motion generation framework based on a frequency-domain diffusion model,which aims to better model complex motion distributions and enhance generation stability under sparse conditions.Our method maps motion sequences to the frequency domain via the Discrete Cosine Transform(DCT),enabling more effective modeling of low-frequency motion structures while suppressing high-frequency noise.A denoising network based on self-attention is introduced to capture long-range temporal dependencies and improve global structural awareness.Additionally,a multi-objective loss function is employed to jointly optimize motion smoothness,pose diversity,and anatomical consistency,enhancing the realism and physical plausibility of the generated sequences.Comparative experiments on the Human3.6M and LaFAN1 datasets demonstrate that our method outperforms state-of-the-art approaches across multiple performance metrics,showing stronger capabilities in generating intermediate motion frames.This research offers a new perspective and methodology for human motion generation and holds promise for applications in character animation,game development,and virtual interaction. 展开更多
关键词 Motion generation diffusion model frequency domain human motion synthesis self-attention network 3D motion interpolation
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Effects of noninvasive brain stimulation on motor functions in animal models of ischemia and trauma in the central nervous system
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作者 Seda Demir Gereon R.Fink +1 位作者 Maria A.Rueger Stefan J.Blaschke 《Neural Regeneration Research》 2026年第4期1264-1276,共13页
Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of kn... Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation. 展开更多
关键词 noninvasive brain stimulation preclinical modeling STROKE transcranial direct current stimulation transcranial magnetic stimulation traumatic brain injury
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基于SBM-Undesirable模型的1997-2010年中国公路运输效率评价 被引量:41
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作者 杨良杰 吴威 +2 位作者 苏勤 蒋晓威 卫云龙 《地理科学进展》 CSCD 北大核心 2013年第11期1602-1611,共10页
引入非期望产出评价模型SBM-Undesirable,并基于时空演变的视角,对1997-2010年中国公路运输效率进行了分析。结果表明:①1997-2010年间中国公路运输效率水平整体偏低,且效率水平呈波动下降趋势,其中2008年表现较为突出;②公路运输负外... 引入非期望产出评价模型SBM-Undesirable,并基于时空演变的视角,对1997-2010年中国公路运输效率进行了分析。结果表明:①1997-2010年间中国公路运输效率水平整体偏低,且效率水平呈波动下降趋势,其中2008年表现较为突出;②公路运输负外部效应产出降低了中国公路运输效率的整体水平,而纯技术效率的变化则是影响公路运输综合效率变化的主要因素;③中国公路运输效率存在着较为显著的区域差异性,经济发展水平较高的东部地区运输效率较高,经济发展水平较低的中西部地区运输效率较低,且这种差异性有不断扩大的趋势;④在空间视角上,中国公路运输效率均衡性趋于降低,近年来由相对均衡逐步向非均衡甚至极化趋势发展;⑤提高资源利用效率、优化资源配置能力、减少负外部效应产出和增加运输有效产出是改善运输效率的重要途径。 展开更多
关键词 公路运输效率 sbm-undesirable模型 非期望产出 时空演变 中国
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Novel therapies for myasthenia gravis:Translational research from animal models to clinical application
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作者 Benedetta Sorrenti Christian Laurini +4 位作者 Luca Bosco Camilla Mirella Maria Strano Adele Ratti Yuri Matteo Falzone Stefano Carlo Previtali 《Neural Regeneration Research》 2026年第5期1834-1848,共15页
Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in ... Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in their serum, targeting acetylcholine receptor, muscle-specific kinase, or related proteins. Current treatment for myasthenia gravis involves symptomatic therapy, immunosuppressive drugs such as corticosteroids, azathioprine, and mycophenolate mofetil, and thymectomy, which is primarily indicated in patients with thymoma or thymic hyperplasia. However, this condition continues to pose significant challenges including an unpredictable and variable disease progression, differing response to individual therapies, and substantial longterm side effects associated with standard treatments(including an increased risk of infections, osteoporosis, and diabetes), underscoring the necessity for a more personalized approach to treatment. Furthermore, about fifteen percent of patients, called “refractory myasthenia gravis patients”, do not respond adequately to standard therapies. In this context, the introduction of molecular therapies has marked a significant advance in myasthenia gravis management. Advances in understanding myasthenia gravis pathogenesis, especially the role of pathogenic antibodies, have driven the development of these biological drugs, which offer more selective, rapid, and safer alternatives to traditional immunosuppressants. This review aims to provide a comprehensive overview of emerging therapeutic strategies targeting specific immune pathways in myasthenia gravis, with a particular focus on preclinical evidence, therapeutic rationale, and clinical translation of B-cell depletion therapies, neonatal Fc receptor inhibitors, and complement inhibitors. 展开更多
关键词 acetylcholine receptor(AChR) animal models B-cell depletion biological therapies COMPLEMENT IMMUNOTHERAPY muscle-specific kinase(Mu SK) neonatal Fc receptor
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Human cerebral organoids:Complex,versatile,and human-relevant models of neural development and brain diseases
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作者 Raquel Coronel Rosa González-Sastre +8 位作者 Patricia Mateos-Martínez Laura Maeso Elena Llorente-Beneyto Sabela Martín-Benito Viviana S.Costa Gagosian Leonardo Foti Ma Carmen González-Caballero Victoria López-Alonso Isabel Liste 《Neural Regeneration Research》 2026年第3期837-854,共18页
The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cereb... The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cerebral organoids have emerged as valuable tools offering a more complex,versatile,and human-relevant system than traditional animal models,which are often unable to replicate the intricate architecture and functionality of the human brain.Since human cerebral organoids are a state-of-the-art model for the study of neurodevelopment and different pathologies affecting the brain,this field is currently under constant development,and work in this area is abundant.In this review,we give a complete overview of human cerebral organoids technology,starting from the different types of protocols that exist to generate different human cerebral organoids.We continue with the use of brain organoids for the study of brain pathologies,highlighting neurodevelopmental,psychiatric,neurodegenerative,brain tumor,and infectious diseases.Because of the potential value of human cerebral organoids,we describe their use in transplantation,drug screening,and toxicology assays.We also discuss the technologies available to study cell diversity and physiological characteristics of organoids.Finally,we summarize the limitations that currently exist in the field,such as the development of vasculature and microglia,and highlight some of the novel approaches being pursued through bioengineering. 展开更多
关键词 assembloids BIOENGINEERING challenges disease modeling drug screening and toxicology human brain organoids human pluripotent stem cells neurodegenerative diseases NEURODEVELOPMENT VASCULARIZATION
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基于SBM-Undesirable和Meta-frontier模型的城市建设用地利用效率研究 被引量:33
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作者 聂雷 郭忠兴 彭冲 《资源科学》 CSSCI CSCD 北大核心 2017年第5期836-845,共10页
提高建设用地利用效率是今后及未来一段时期满足城市建设用地需求的关键之举。在考虑非期望性产出(环境污染)的情况下,论文基于中国238个地级市2000-2014年的面板数据,利用SBM-Undesirable和Metafrontier模型,考察了共同前沿、群组前沿... 提高建设用地利用效率是今后及未来一段时期满足城市建设用地需求的关键之举。在考虑非期望性产出(环境污染)的情况下,论文基于中国238个地级市2000-2014年的面板数据,利用SBM-Undesirable和Metafrontier模型,考察了共同前沿、群组前沿下不同类型城市的建设用地利用效率。结果表明:(1)不同类型城市之间的建设用地利用效率存在显著差异,在共同前沿下,2000-2010年效率均值从高到低依次为区域综合型城市、工业主导型城市、其他类型城市、资源型城市;在群组前沿下,效率均值没有呈现明显的城市类型分异特征。(2)比较共同前沿与群组前沿下不同类型城市的建设用地利用效率,其他类型城市与区域综合型城市相差较小,分别为0.082、0.106,其次工业主导型城市,为0.118,排在末位的是资源型城市,达到0.267,共同前沿下的差异与群组前沿下的无分异,恰恰印证了本文从城市类型异质性视角下考察建设用地利用效率的科学性与合理性。(3)在将环境污染作为一种非期望性产出的情况下,建设用地利用效率普遍偏低,特别是资源型城市,效率均值不超过0.6,说明在加强生态文明建设的背景下,城市建设用地利用效率存在很大的改善空间。据此提出:在改善城市土地管理工作时,不能简单"一刀切",应考虑城市类型异质性,制定差别化的城市土地管理方案。 展开更多
关键词 城市类型 建设用地利用效率 sbm-undesirable模型 Meta-frontier模型 非期望性产出
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雾霾约束下中国环境技术效率测度及影响因素研究——基于SBM-Undesirable的省际面板数据 被引量:20
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作者 何枫 马栋栋 祝丽云 《研究与发展管理》 CSSCI 北大核心 2016年第5期34-43,共10页
将雾霾这一新的约束条件纳入环境技术效率研究框架,基于2001—2012年省际面板数据,运用SBMUndesirable方法测算了雾霾约束条件下的各地区环境技术效率,重点探讨了技术创新与环境规制强度对环境技术效率的影响.效率测算结果显示:雾霾约... 将雾霾这一新的约束条件纳入环境技术效率研究框架,基于2001—2012年省际面板数据,运用SBMUndesirable方法测算了雾霾约束条件下的各地区环境技术效率,重点探讨了技术创新与环境规制强度对环境技术效率的影响.效率测算结果显示:雾霾约束下中国整体环境技术效率平均值仅为0.616,环境技术效率水平提升空间较大;环境技术效率区域发展不平衡,东、中、西部地区环境技术效率水平依次下降;各省市环境技术效率差异显著;各地区节能减霾潜力巨大.进一步的效率影响因素分析表明,当前的技术创新、环境规制强度并未能显著改变雾霾污染现状以及提升环境技术效率,经济规模、外资依存度、人口密度及地理位置因素均可以促进环境技术效率提升,产业结构和贸易依存度则有负向作用. 展开更多
关键词 雾霾 PM2.5 sbm-undesirable模型 环境技术效率 技术创新 环境规制
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中国农业碳排放绩效评价及随机性收敛研究——基于SBM-Undesirable模型与面板单位根检验 被引量:47
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作者 吴昊玥 何艳秋 陈柔 《中国生态农业学报》 CSCD 北大核心 2017年第9期1381-1391,共11页
当前,全局层面及工业视角下的碳排放绩效评价和收敛性分析已趋于成熟,但农业碳排放方面的研究尚十分薄弱。为补充相关研究,对区域农业碳排放总量、绩效及两者的收敛趋势有更清晰的认识,本文在测算2000—2014年我国30个省市农业碳排放总... 当前,全局层面及工业视角下的碳排放绩效评价和收敛性分析已趋于成熟,但农业碳排放方面的研究尚十分薄弱。为补充相关研究,对区域农业碳排放总量、绩效及两者的收敛趋势有更清晰的认识,本文在测算2000—2014年我国30个省市农业碳排放总量的基础上,运用SBM-Undesirable模型计算农业碳排放绩效,并通过面板单位根检验方法对全国和各区域的农业碳排放总量及绩效进行了随机性收敛检验。结果显示:1)2000—2014年间,全国农业碳排放量整体呈递增趋势,但各区域排放量差异明显。比较中部与全国、东部和西部各年总量均值,发现2000年的差值分别为3.357 4?106 t,3.965 0?106 t和5.904 7?106 t,到2014年,差距扩大至5.244 8?106 t,7.351 2?106 t和7.681 0?106 t,对应增长比例分别为56.2%、85.4%和30.0%。2)各区域农业碳排放绩效存在显著差异。绩效均值折线图显示,东部平均绩效较高,15年来基本稳定在0.8左右;西部和中部绩效均值较低,绝大多数年份处于0.3~0.5,但西部不断改善,中部则持续下降。3)对总量进行收敛性检验,发现全国、西部、中部呈现明显的随机性分异,仅东部出现随机性趋同;在绩效的收敛性检验中,全国范围内不存在随机性收敛,但东部、中部、西部各自呈俱乐部式随机性收敛态势。随机性收敛检验结果表明,中国农业碳排放总量和绩效不会自动降低到稳态水平,有必要进行相关政策干预,以缩小各省市间的差距。本研究为制定区域间差异化和区域内统一性农业减排政策奠定了基础。 展开更多
关键词 农业碳排放 碳排放绩效 sbm-undesirable模型 面板单位根 随机性收敛 俱乐部收敛
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基于SBM-Undesirable模型的我国三大城市群经济增长效率研究 被引量:15
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作者 苑清敏 邱静 冯东 《干旱区资源与环境》 CSSCI CSCD 北大核心 2015年第9期7-12,共6页
文中选取京津冀、长三角和珠三角35个城市2005-2012年的面板数据,运用基于产出角度的SBM-Undesirable模型,对我国三大城市群经济增长效率进行了研究。研究发现,我国三大城市群经济增长效率存在明显异质性,平均效率水平的区域分布为:珠三... 文中选取京津冀、长三角和珠三角35个城市2005-2012年的面板数据,运用基于产出角度的SBM-Undesirable模型,对我国三大城市群经济增长效率进行了研究。研究发现,我国三大城市群经济增长效率存在明显异质性,平均效率水平的区域分布为:珠三角>长三角>京津冀。同时,三大城市群经济增长效率空间分布均呈现不均衡特征,其中京津冀城市群中经济增长效率较高的城市主要集中于环渤海地区;长三角城市群相对有效城市主要集中于江苏以及浙北的绍兴和台州;珠三角城市群在2012年大部分城市均达到相对有效性。 展开更多
关键词 三大城市群 经济增长效率 sbm-undesirable 非期望产出
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雾霾约束下中国省际区间环境技术效率研究——基于SBM-Undesirable区间模型的面板数据分析 被引量:6
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作者 何枫 马栋栋 徐晓宁 《干旱区资源与环境》 CSSCI CSCD 北大核心 2016年第12期28-33,共6页
文中首次将雾霾纳入环境技术效率研究框架,构建了考虑非期望产出的SBM区间模型,测算了2001-2012年雾霾约束下中国省际区间环境技术效率。结果表明:1)中国整体区间环境技术效率不高且在逐渐下降。区间DEA部分有效、有效、无效省份数依次... 文中首次将雾霾纳入环境技术效率研究框架,构建了考虑非期望产出的SBM区间模型,测算了2001-2012年雾霾约束下中国省际区间环境技术效率。结果表明:1)中国整体区间环境技术效率不高且在逐渐下降。区间DEA部分有效、有效、无效省份数依次减少。2)东、中、西部地区区间环境技术效率差异显著,具有明显的不平衡发展态势。3)横截面各省市区间环境技术效率差异明显,具有较大提升空间;纵向时序各省市区间环境技术效率有效年份较少,且有效性省份数呈减少态势。所得评价结果能够反映出中国省际区间环境技术效率真实水平,并可为中国雾霾治理提供决策参考。 展开更多
关键词 雾霾约束 PM2.5 sbm-undesirable区间模型 区间环境技术效率
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中国工业生态全要素能源效率异质性研究——基于SBM-Undesirable和Meta-frontier模型的分析 被引量:14
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作者 陈平 罗艳 《商业研究》 CSSCI 北大核心 2017年第4期154-160,共7页
为了克服以往区域经济研究中的生产技术异质性问题,采用SBM-Undesirable模型和Meta-frontier生产函数测算我国30个省市2004-2014年的工业生态全要素能源效率,同时采用"共同技术比率"测算各地区能源利用的技术差距,并从"... 为了克服以往区域经济研究中的生产技术异质性问题,采用SBM-Undesirable模型和Meta-frontier生产函数测算我国30个省市2004-2014年的工业生态全要素能源效率,同时采用"共同技术比率"测算各地区能源利用的技术差距,并从"管理无效率"和"技术无效率"两个维度分析能源利用无效率的来源及其影响因素。总体上看,我国三大群组共同前沿生态全要素能源效率(MTE)和共同技术比率(MTR)区域差异较为明显,呈现出"东-中-西"依次递减的格局,而群组前沿生态全要素能源效率(GTE)呈现出"西-中-东"依次递减的格局;生态全要素能源利用无效率均值分解来看,东部群组能源利用无效率是因为管理无效率造成的,中部群组技术无效率和管理无效率同时显著存在,而西部群组技术无效率最为明显,产业结构、对外开放、研发投入、环境规制、政府干预对生态全要素能源效率产生显著而有差异的影响。 展开更多
关键词 生态全要素能源效率 sbm-undesirable模型 共同前沿函数 共同技术比率
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基于SBM-undesirable和Meta-frontier模型的APEC能源效率研究 被引量:11
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作者 陶雪萍 王平 朱帮助 《北京理工大学学报(社会科学版)》 CSSCI 2015年第2期20-28,共9页
准确测算能源效率与提升潜力可以为制定有效的节能减排策略提供科学依据。为进一步完善跨国研究中由于技术异质性导致的能源效率测算偏差,采用SBM-Undesirable模型和Meta-frontier生产函数,测算了APEC17个成员1990—2012年期间的能源效... 准确测算能源效率与提升潜力可以为制定有效的节能减排策略提供科学依据。为进一步完善跨国研究中由于技术异质性导致的能源效率测算偏差,采用SBM-Undesirable模型和Meta-frontier生产函数,测算了APEC17个成员1990—2012年期间的能源效率。同时,采用"共同技术比率"定量考察了各成员能源利用的技术差距,并从"生产技术"和"管理"两个维度将能源利用无效率分解为"技术差距无效率"和"管理无效率"来探寻能源效率提升途径。研究发现:发达国家和地区在共同前沿和群组前沿下的能源效率没有差异,发展中国家和地区在两种前沿下的能源效率有显著差异;发展中国家与潜在的最优技术水平的差距有扩大的趋势;发达国家和地区应从管理方面提高能源效率,发展中国家和地区则要从技术和管理双方面来提高能源效率。 展开更多
关键词 sbm-undesirable模型 共同前沿生产函数 共同技术比率 技术差距无效率 管理无效率
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“美丽中国”背景下中国区域产业转移对工业绿色效率的影响研究——基于SBM-undesirable模型和空间计量模型 被引量:9
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作者 呙小明 黄森 《重庆大学学报(社会科学版)》 CSSCI 北大核心 2018年第4期1-11,共11页
区域产业转移一方面促进了地区间产业的协同发展,另一方面也给部分产业承接区域带来了显著的环境问题。在建设人与自然和谐共生的"美丽中国"背景下,如何保证区域产业转移过程中,经济增长与环境保护可持续发展等问题值得深思... 区域产业转移一方面促进了地区间产业的协同发展,另一方面也给部分产业承接区域带来了显著的环境问题。在建设人与自然和谐共生的"美丽中国"背景下,如何保证区域产业转移过程中,经济增长与环境保护可持续发展等问题值得深思。选择绿色经济为切入点,基于SBM-undesirable模型和空间计量模型对2006—2015年中国工业省际数据进行测算,研究表明,中国工业整体发展并没有达到绿色有效的水平,绿色效率呈波动中下降的趋势;空间局域LISA指数显示中国区域间工业绿色效率差异较大,表现出"东优西劣"的集聚格局;空间滞后计量模型表明产业转移和政府规制并未能带动工业绿色效率的提高;最后,据此提出未来中国工业在区域间均衡、可持续发展的相关对策建议。 展开更多
关键词 sbm-undesirable模型 空间计量模型 工业绿色效率 区域产业转移
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