期刊文献+
共找到1,008,519篇文章
< 1 2 250 >
每页显示 20 50 100
A novel coupled progressive corrosion-water hammer inrush model for deep coal seam floors
1
作者 Genshui Wu Jianping Zuo Lisong Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期416-440,共25页
The mining industry is frequently subjected to various disasters,one of the major concerns is water-related disasters,particularly seam floor water inrush.These disasters pose significant threats to the safety and pro... The mining industry is frequently subjected to various disasters,one of the major concerns is water-related disasters,particularly seam floor water inrush.These disasters pose significant threats to the safety and production of deep coal mines.The primary reason for this is that the fracturing of the rock mass induces the formation of a fluid(water)with both kinetic and potential energy.In this paper,a novel water inrush mechanism for deep floor failure due to water hammer effects is proposed based on the Xingdong coal mine in China.The water hammer pressure within rock pore channels has a different impact on the surrounding rock,leading to the degradation of the rock mass channel through repeated conduction and instantaneous cutoff.To further investigate this phenomenon,a progressive corrosion fracture mechanics(PCFM)model induced by a water hammer is established.The results show that the water hammer pressure caused by instantaneous channel truncation increases with increasing water flow velocity.The chemical damage factor(i.e.,stress corrosion fracture)is also incorporated into the Dugdale-Barenblatt(D-B)model to analyze the factors influencing the PCFM.These findings indicate that the greater the degree of damage is,the more likely the concealed fault is to experience water inrush.Finally,methods for controlling water inrush caused by the water hammer effects of deep floors are proposed.The failure mechanisms of the water hammer and the PCFM provide theoretical and practical guidance for controlling water inrush from the deep floor. 展开更多
关键词 Water hammer Rock mechanics Fracture mechanics progressive corrosion damage Water inrush
在线阅读 下载PDF
Meso-progressive failure and damage constitutive model of fractured sandstone under uniaxial loading-unloading in freeze-thaw environments
2
作者 Hao Tan Yongjun Song +1 位作者 Huimin Yang Yongxin Che 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第12期7950-7965,共16页
High-altitude cold regions exhibit complex geological and environmental conditions,fostering steep rock slopes with macroscopic joints and mesoscopic freeze-thaw(F-T)damage.Cyclic loading further exacerbates rock inst... High-altitude cold regions exhibit complex geological and environmental conditions,fostering steep rock slopes with macroscopic joints and mesoscopic freeze-thaw(F-T)damage.Cyclic loading further exacerbates rock instability,yet the fracture mechanisms and load response relationships remain poorly understood.This study prepared intact and fractured sandstone specimens,subjected them to F-T cycles and graded loading-unloading,and monitored their structural evolution via X-ray computed tomography.First,the progressive failure process was investigated from both qualitative morphologic features and quantitative void parameters.The results showed that intact and fractured sandstone instability behaviors are determined by F-T damage and joint arrangement,respectively.However,both indicate that precursory localization of failure can only be detected when heterogeneous damage exists in advance.Furthermore,the void parameters of undamaged intact sandstone exhibit power-law acceleration,while damaged sandstones are characterized by a trend of initial decrease followed by an increase.Subsequently,a damage constitutive model for freeze-thawed fractured sandstone under graded loading-unloading was established.This model is based on the Lemaitre strain equivalence hypothesis and defines the coupled damage variable through multivariable indicators.In this framework,the material damage induced by fractures and F-T is unified and characterized by void parameters;while the load-induced damage is integrated with the energy linear allocation law and defined by damage energy.Thus,the stress-strain theoretical relationship is depicted,and the model is validated as reliable.Finally,a conceptual model of rock damage due to F-T and loading-unloading was proposed by combining the microscopic testing results from X-ray diffraction and scanning electron microscopy. 展开更多
关键词 Fractured sandstone FREEZE-THAW Loading-unloading progressive failure Damage constitutive model
在线阅读 下载PDF
A New Extension Odd Generalized Exponential Model Using Type-Ⅱ Progressive Censoring and Its Applications in Engineering and Medicine
3
作者 Zohra A.Esaadi Rabab S.Gomaa +2 位作者 Beih S.El-Desouky Ehab M.Almetwally Alia M.Magar 《Computer Modeling in Engineering & Sciences》 2025年第8期2063-2097,共35页
A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical pro... A new extended distribution called the Odd Exponential Generalized Exponential-Exponential distribution(EOEGE-E)is proposed based on generalization of the odd generalized exponential family(OEGE-E).The statistical properties of the proposed distribution are derived.The study evaluates the accuracy of six estimation methods under complete samples.Estimation techniques include maximumlikelihood,ordinary least squares,weighted least squares,maximumproduct of spacing,Cramer vonMises,and Anderson-Darling methods.Twomethods of estimation for the involved parameters are considered based on progressively type Ⅱ censored data(PTⅡC).These methods are maximum likelihood and maximum product of spacing.The proposed distribution’s effectiveness was evaluated using different data sets from various fields.The proposed distribution provides a better fit for these datasets than existing probability distributions. 展开更多
关键词 Odd generalized exponential distribution likelihood and product of spacing progressive censoring progressive typeⅡcensoring
在线阅读 下载PDF
Research and Practice on the Progressive Training Model of Meizhou Hakka Cuisine Cooking Talents Based on the Integration of Industry and Education and Work-Study Alternation
4
作者 Ganhong Chen Yong Liu +1 位作者 Pingping Luo Weirun Liang 《Journal of Contemporary Educational Research》 2025年第9期275-281,共7页
The development of Meizhou Hakka cuisine relies on the role of professional cooking talents.Higher vocational colleges serve as the platform for cultivating cooking talents.Among various training models,the implementa... The development of Meizhou Hakka cuisine relies on the role of professional cooking talents.Higher vocational colleges serve as the platform for cultivating cooking talents.Among various training models,the implementation of the progressive talent training model featuring the integration of industry and education and work-study alternation is conducive to carrying out talent cultivation activities,improving the effectiveness of professional talent development,and effectively meeting the needs of market development.From the perspective of Meizhou Hakka cuisine cooking talents,this paper analyzes the problems existing in the implementation of the industry-education integration and work-study alternation model,and puts forward specific practical strategies for talent cultivation.The purpose is to enhance the training effect of Hakka cuisine cooking talents and provide reference for the subsequent optimization of professional teaching. 展开更多
关键词 Integration of industry and education Work-study alternation Meizhou Hakka cuisine progressive talent training
在线阅读 下载PDF
Therapeutic Potential of Fingolimod and Dimethyl Fumarate in Preclinical Pancreatic Cancer Models
5
作者 Pauline Gousseau Laurie Genest +1 位作者 Guillaume Froget Tristan Rupp 《Oncology Research》 2026年第3期387-405,共19页
Objectives:The five-year survival rate for pancreatic cancer is notably low,posing a significant challenge to patient health.The primary treatments are radiotherapy and chemotherapy,sometimes combined with targeted th... Objectives:The five-year survival rate for pancreatic cancer is notably low,posing a significant challenge to patient health.The primary treatments are radiotherapy and chemotherapy,sometimes combined with targeted therapy;however,their clinical benefits are limited.Therefore,developing new models to evaluate the therapeutic potential of novel molecules is essential.Fingolimod and Dimethyl Fumarate(DMF),currently used to treat multiple sclerosis,have recently been shown to have anti-cancer effects in several preclinical tumor models.This study aims to evaluate the therapeutic potential of Fingolimod and DMF in pancreatic cancer by investigating their respective in vitro cytotoxicity and in vivo antitumor effects.Methods:In this study,we evaluated for the first time these two drugs in pancreatic preclinical models in vitro using 3D spheroid tumor models and in vivo,which are compared to two standard-of-care consisting of Gemcitabine and Erlotinib.Results:In vitro,both Fingolimod and DMF induced cytotoxicity in spheroids from two pancreatic cell lines.Additionally,Fingolimod and DMF displayed anticancer effects in two subcutaneous xenograft models using PANC-1 and CFPAC-1 cells.Conclusions:Although the responses observed with Fingolimod and DMF were similar to those of Gemcitabine and Erlotinib,these findings indicate a potential emerging interest in Fingolimod and DMF for the treatment of pancreatic cancer.However,further work is still necessary to fully characterize how these drugs affect tumor progression. 展开更多
关键词 Pancreatic cancer preclinical models tumor progression FINGOLIMOD dimethyl Fumarate
暂未订购
Progressive fatigue damage modelling and life prediction of 3D four-directional braided composite I-beam under four-point flexure spectrum loading
6
作者 Dong LI Junjiang XIONG 《Chinese Journal of Aeronautics》 2025年第3期65-84,共20页
This paper aims to experimentally and numerically probe fatigue behaviours and lifetimes of 3D4D(three-dimensional four-directional)braided composite I-beam under four-point flexure spectrum loading.New fatigue damage... This paper aims to experimentally and numerically probe fatigue behaviours and lifetimes of 3D4D(three-dimensional four-directional)braided composite I-beam under four-point flexure spectrum loading.New fatigue damage models of fibre yarn,matrix and fibre–matrix interface are proposed,and fatigue failure criteria and PFDA(Progressive Fatigue Damage Algorithm)are thus presented for meso-scale fatigue damage modelling of 3D4D braided composite I-beam.To validate the aforementioned model and algorithm,fatigue tests are conducted on the 3D4D braided composite I-beam under four-point flexure spectrum loading,and fatigue failure mechanisms are analyzed and discussed.Novel global–local FE(Finite Element)model based on the PFDA is generated for modelling progressive fatigue failure process and predicting fatigue life of 3D4D braided composite I-beam under four-point flexure spectrum loading.Good agreement has been achieved between experimental results and predictions,demonstrating the effective usage of new model.It is shown that matrix cracking and interfacial debonding initially initiates on top surface of top flange of I-beam,and then gradually propagates from the side surface of top flange to the intermediate web along the braiding angle,and considerable fiber breakage finally causes final fatigue failure of I-beam. 展开更多
关键词 Three-dimensional four-directional Braided composite I-BEAM Four-point flexure Fatigue life prediction progressive fatigue damage Fatigue damage Finite element method
原文传递
Functional generalized estimating equation model to detect glaucomatous visual field progression
7
作者 Sanghun Jeong Hwayeong Kim +4 位作者 Sangwoo Moon EunAh Kim Hojin Yang Jiwoong Lee Kouros Nouri-Mahdavi 《International Journal of Ophthalmology(English edition)》 2026年第2期302-311,共10页
AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:... AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:Totally 716 eyes of 716 patients with primary open angle glaucoma(POAG)with at least 5 reliable 24-2 test results and 2y of follow-up were selected.The functional GEE model was used to detect perimetric progression in the training dataset(501 eyes).In the testing dataset(215 eyes),progression was evaluated the functional GEE model,mean deviation(MD)and visual field index(VFI)rates of change,Advanced Glaucoma Intervention Study(AGIS)and Collaborative Initial Glaucoma Treatment Study(CIGTS)scores,and pointwise linear regression(PLR).RESULTS:The proposed method showed the highest proportion of eyes detected as progression(54.4%),followed by the VFI rate(34.4%),PLR(23.3%),and MD rate(21.4%).The CIGTS and AGIS scores had a lower proportion of eyes detected as progression(7.9%and 5.1%,respectively).The time to detection of progression was significantly shorter for the proposed method than that of other algorithms(adjusted P≤0.019).The VFI rate displayed moderate pairwise agreement with the proposed method(k=0.47).CONCLUSION:The functional GEE model shows the highest proportion of eyes detected as perimetric progression and the shortest time to detect perimetric progression in patients with POAG. 展开更多
关键词 functional generalized estimating equation model primary open angle glaucoma perimetric progression
原文传递
A decision framework for rural domestic sewage treatment models and process:Evidence from Inner Mongolia Autonomous Region,China 被引量:1
8
作者 Ying Yan Pengyu Li +5 位作者 Zixuan Wang Yubo Tan Tianlong Zheng Jianguo Liu Xiaoxia Yang Junxin Liu 《Journal of Environmental Sciences》 2026年第1期302-311,共10页
Rural domestic sewage treatment is critical for environmental protection.This study defines the spatial pattern of villages from the perspective of rural sewage treatment and develops an integrated decision-making sys... Rural domestic sewage treatment is critical for environmental protection.This study defines the spatial pattern of villages from the perspective of rural sewage treatment and develops an integrated decision-making system to propose a sewage treatment mode and scheme suitable for local conditions.By considering the village spatial layout and terrain factors,a decision tree model of residential density and terrain type was constructed with accuracies of 76.47%and 96.00%,respectively.Combined with binary classification probability unit regression,an appropriate sewage treatment mode for the village was determined with 87.00%accuracy.The Analytic Hierarchy Process(AHP),combined with the Technique for Order Preference(TOPSIS)by Similarity to an Ideal Solution model,formed the basis for optimal treatment process selection under different emission standards.Verification was conducted in 542 villages across three counties of the Inner Mongolia Autonomous Region,focusing on the standard effluent effect(0.3773),low investment cost(0.3196),and high standard effluent effect(0.5115)to determine the best treatment process for the same emission standard under different needs.The annual environmental and carbon emission benefits of sewage treatment in these villages were estimated.This model matches village density,geographic feature,and social development level,and provides scientific support and a theoretical basis for rural sewage treatment decision-making. 展开更多
关键词 Rural domestic sewage Sewage treatment model DECISION-MAKING Environmental-economic benefits Inner Mongolia
原文传递
Description and Evaluation of the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)Model Version 1.0 被引量:1
9
作者 EPICC Model Working Group 《Advances in Atmospheric Sciences》 2026年第4期671-694,I0001-I0006,共30页
We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework... We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework incorporates(1)grid configuration,(2)transport dynamics,(3)chemical mechanisms,(4)aerosol processes,(5)wet/dry deposition parameterizations,and(6)heterogeneous chemistry treatments associated with sulfate,nitrous acid(HONO)chemistry,and aerosol/cloud–photolysis interactions(APIs/CPIs).Openly shared with the atmospheric research community,the model facilitates integration of advanced physicochemical schemes to enhance simulation accuracy.Globally,the model demonstrates realistic representations of ozone(O_(3))and aerosol optical depth.The EPICC model generally demonstrates robust performance in simulating regional concentrations of O_(3) and PM_(2.5)(and its components)in China.It successfully captures vertical profiles of both global and regional O_(3).Notably,the model mitigates frequently reported sulfate underestimations in highly industrialized regions of China.The model accurately captures two regional severe pollution episodes observed in eastern China(January/June 2021).Sensitivity experiments highlight the critical roles of heterogeneous chemical mechanisms associated with sulfate,HONO chemistry,APIs,and CPIs in capturing PM_(2.5) and O_(3) concentrations in China.Improved sulfate mechanisms result in an increase of approximately 32.4%(2.8μg m^(−3))in simulated winter sulfate concentrations when observations exceed 10μg m^(−3).Enhanced HONO elevates winter O_(3) and PM_(2.5) by≤20 and≤10μg m^(−3),respectively.Overall,CPIs dominate over APIs in improving O_(3) and PM_(2.5) simulations across China.Locally,APIs mitigate PM_(2.5) and O_(3) discrepancies in the Sichuan Basin.Seasonal cloud–chemistry coupling explains the weaker impact of PM_(2.5) in summer. 展开更多
关键词 EPICC model PM_(2.5) O_(3) sulfate nitrous acid aerosol/cloud-photolysis interactions
在线阅读 下载PDF
Agri-Eval:Multi-level Large Language Model Valuation Benchmark for Agriculture
10
作者 WANG Yaojun GE Mingliang +2 位作者 XU Guowei ZHANG Qiyu BIE Yuhui 《农业机械学报》 北大核心 2026年第1期290-299,共10页
Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLM... Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLMs.Therefore,in order to better assess the capability of LLMs in the agricultural domain,Agri-Eval was proposed as a benchmark for assessing the knowledge and reasoning ability of LLMs in agriculture.The assessment dataset used in Agri-Eval covered seven major disciplines in the agricultural domain:crop science,horticulture,plant protection,animal husbandry,forest science,aquaculture science,and grass science,and contained a total of 2283 questions.Among domestic general-purpose LLMs,DeepSeek R1 performed best with an accuracy rate of 75.49%.In the realm of international general-purpose LLMs,Gemini 2.0 pro exp 0205 standed out as the top performer,achieving an accuracy rate of 74.28%.As an LLMs in agriculture vertical,Shennong V2.0 outperformed all the LLMs in China,and the answer accuracy rate of agricultural knowledge exceeded that of all the existing general-purpose LLMs.The launch of Agri-Eval helped the LLM developers to comprehensively evaluate the model's capability in the field of agriculture through a variety of tasks and tests to promote the development of the LLMs in the field of agriculture. 展开更多
关键词 large language models assessment systems agricultural knowledge agricultural datasets
在线阅读 下载PDF
Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
11
作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
在线阅读 下载PDF
MRFNet:A Progressive Residual Fusion Network for Blind Multiscale Image Deblurring
12
作者 Wang Zhang Haozhuo Cao Qiangqiang Yao 《Computers, Materials & Continua》 2026年第3期1851-1866,共16页
Recent advances in deep learning have significantly improved image deblurring;however,existing approaches still suffer from limited global context modeling,inadequate detail restoration,and poor texture or edge percep... Recent advances in deep learning have significantly improved image deblurring;however,existing approaches still suffer from limited global context modeling,inadequate detail restoration,and poor texture or edge perception,especially under complex dynamic blur.To address these challenges,we propose the Multi-Resolution Fusion Network(MRFNet),a blind multi-scale deblurring framework that integrates progressive residual connectivity for hierarchical feature fusion.The network employs a three-stage design:(1)TransformerBlocks capture long-range dependencies and reconstruct coarse global structures;(2)Nonlinear Activation Free Blocks(NAFBlocks)enhance local detail representation and mid-level feature fusion;and(3)an optimized residual subnetwork based on gated feature modulation refines texture and edge details for high-fidelity restoration.Extensive experiments demonstrate that MRFNet achieves superior performance compared to state-of-the-art methods.On GoPro,it attains 32.52 dB Peak Signal-to-Noise Ratio(PSNR)and 0.071 Learned Perceptual Image Patch Similarity(LPIPS),outperforming MIMOWNet(32.50 dB,0.075).On HIDE,it achieves 30.25 dB PSNR and 0.945 Structural Similarity Index Measure(SSIM),representing gains of+0.26 dB and+0.015 SSIM over MIMO-UNet(29.99 dB,0.930).On RealBlur-J,it reaches 28.82 dB PSNR and 0.872 SSIM,surpassing MIMO-UNet by+1.19 dB and+0.035 SSIM(27.63 dB,0.837).These results validate the effectiveness of the proposed progressive residual fusion and hybrid attention mechanisms in balancing global context understanding and local detail recovery for blind image deblurring. 展开更多
关键词 Blind deblurring progressive network multi-scale features residual structure
在线阅读 下载PDF
Illusion of inactivity:Revisiting progressive multiple sclerosis treatment paradigms
13
作者 Tal Ganz Tamir Ben-Hur 《Neural Regeneration Research》 2026年第3期1134-1135,共2页
Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory v... Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory versus degenerative dichotomy.This was based on a broad misconception regarding essentially all neurodegenerative conditions,depicting the degenerative process as passive and immune-independent occurring as a late byproduct of active inflammation in the central nervous system(CNS),which is(solely)systemically driven. 展开更多
关键词 inflammatory versus degenerative dichotomythis treatment paradigms illusion inactivity multiple sclerosis traditionallythe central nervous system cns which progressive multiple sclerosis active inflammation progressive multiple sclerosis pms
暂未订购
Special Issue“Recent Developments in Dimension Reduction and Model Checking”——In Honor of Professor Lixing Zhu's Outstanding Contributions in Statistics
14
作者 ZHU Liping XU Wangli LI Yingxing 《Journal of Systems Science & Complexity》 2026年第1期1-2,共2页
The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pil... The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pillars supporting scientific inference and data-driven decisionmaking,have evolved through the collective wisdom of generations of statisticians.This special issue,titled"Recent Developments in Dimension Reduction and Model Checking for regressions",not only aims to showcase cutting-edge advances in the field but also carries a distinct sense of academic homage to honor the groundbreaking and enduring contributions of Professor Lixing Zhu,a leading scholar whose work has profoundly shaped both areas. 展开更多
关键词 scientific inference model checking model checkingas complex models dimension reduction high dimensional data
原文传递
Ecosystem service models are indeed being validated:A response to Pereira et al.(2025)
15
作者 James M.Bullock Danny A.P.Hooftman +1 位作者 John W.Redhead Simon Willcock 《Geography and Sustainability》 2026年第1期247-248,共2页
In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation ... In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation is provided”and that“the validation step is largely overlooked”.This assertion may have been true several years ago,for example,when Ochoa and Urbina-Cardona(2017)made a similar observation.However,there has been much work on ES model validation over the last decade. 展开更多
关键词 evaluation MAPPING modeling es model ecosystem services VALIDATION
在线阅读 下载PDF
Efficient Model Reduction of Linear Time-varying Systems via Shifted Legendre Polynomial Approximations
16
作者 XIAO Zhihua TANG Man ZHU Zhihui 《应用数学》 北大核心 2026年第2期481-493,共13页
This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramia... This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramians directly from the expansion coefficients of impulse responses.Leveraging these factors,we develop two model reduction algorithms that integrate the low-rank square root method with dominant subspace projection.Our method is computationally efficient and flexible,requiring only a few matrix-vector operations and a singular value decomposition of a low-dimensional matrix,thereby avoiding the need to solve differential Lyapunov equations.Numerical experiments confirm the effectiveness of the proposed approach. 展开更多
关键词 model reduction Time-varying systems Low-rank Gramians Balanced truncation Shifted Legendre polynomials
在线阅读 下载PDF
Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
17
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
在线阅读 下载PDF
Preferences of Chinese Dermatologists for Large Language Model Responses in Clinical Psoriasis Scenarios:A Nationwide Cross-Sectional Survey in China
18
作者 Jungang Yang Jingkai Xu +6 位作者 Xuejiao Song Chengxu Li Lili Chen Lingbo Bi Tingting Jiang Xianbo Zuo Yong Cui 《Health Care Science》 2026年第1期40-48,共9页
Background:Large language models(LLMs)have shown considerable promise in supporting clinical decision-making.However,their adoption and evaluation in dermatology remains limited.This study aimed to explore the prefere... Background:Large language models(LLMs)have shown considerable promise in supporting clinical decision-making.However,their adoption and evaluation in dermatology remains limited.This study aimed to explore the preferences of Chinese dermatologists regarding LLM-generated responses in clinical psoriasis scenarios and to assess how they prioritize key quality dimensions,including accuracy,traceability,and logicality.Methods:A cross-sectional,web-based survey was conducted between December 25,2024,and January 22,2025,following the Checklist for Reporting Results of Internet E-Surveys guidelines.A total of 1247 valid responses were collected from practicing dermatologists across 33 of China's provincial-level administrative divisions.Participants evaluated responses to five categories of clinical questions(etiology,clinical presentation,differential diagnosis,treatment,and case study)generated by five LLMs:ChatGPT-4o,Kimi.ai,Doubao,ZuoYiGPT,and Lingyi-agent.Statistical associations between participant characteristics and model preferences were examined using chi-square tests.Results:ChatGPT-4o(Model 1)emerged as the most preferred model across all clinical tasks,consistently receiving the highest number of votes in case study(n=740),clinical presentation(n=666),differential diagnosis(n=707),etiology(n=602),and treatment(n=656).Significant variation in model preference by professional title was observed only for the differential diagnosis task(χ^(2)=21.13,df=12,p=0.0485),while no significant differences were found across hospital tiers(p>0.05).In terms of evaluation dimensions,accuracy was most frequently rated as“very important”(n=635).A significant association existed between hospital tier and the most valued dimension(χ^(2)=27.667,df=9,p=0.0011),with dermatologists in primary hospitals prioritizing traceability more than their peers in higher-tier hospitals.No significant associations were found across professional titles(p=0.127).Conclusions:Chinese dermatologists suggest a strong preference for ChatGPT-4o over domestic LLMs in psoriasis-related clinical tasks.While accuracy remains the primary criterion,traceability and logicality are also critical,particularly for clinicians in lower-tier hospitals.These findings suggest that future clinical LLMs should prioritize not only content accuracy but also source transparency and structural clarity to meet the diverse needs of different clinical settings. 展开更多
关键词 DERMATOLOGY large language model model evaluation
暂未订购
Modeling reaction between high-Al steel and slag with consideration of MgO-refractory dissolution into slag
19
作者 Rong-Zhen Mo Chi-Hao Zhang +1 位作者 Ying Ren Li-Feng Zhang 《Journal of Iron and Steel Research International》 2026年第3期106-115,共10页
The dissolution of MgO-refractory into the slag had an obvious influence on the steel-slag reaction and the slag property,especially for high-aluminum steels.The dissolution behavior of MgO-refractory was investigated... The dissolution of MgO-refractory into the slag had an obvious influence on the steel-slag reaction and the slag property,especially for high-aluminum steels.The dissolution behavior of MgO-refractory was investigated under various conditions,including the temperature,the initial steel composition,and the initial slag composition.A steel-slag-refractory kinetic model for high-aluminum steel was developed,which incorporated the process of MgO-refractory dissolution.The dependence of the MgO mass transfer coefficient k_(MgO)^(r)on temperature T during MgO-refractory dissolution process was established,as described by ln k_(MgO)^(r)=63,754/T+24.38524.It was indicated that the MgO dissolution rate was significantly influenced by the temperature.A higher temperature increased the dissolution rate of MgO.The initial steel composition had a slight impact on the MgO dissolution rate.Additionally,the initial slag composition strongly impacted the MgO saturation concentration and the dissolution rate.A lower initial Al_(2)O_(3)/SiO_(2)ratio increased the MgO dissolution rate.The steel-slag-refractory kinetic model accurately predicted the dissolution of MgO-refractory and the influence of dissolved MgO on the viscosity and composition change during steel-slag-refractory reactions.It was suggested that a higher temperature can hardly reduce the viscosity due to the dissolution of the MgO-refractory. 展开更多
关键词 MgO-refractory Steel-slag-refractory model Kinetic model High-aluminum steel Mold flux
原文传递
Stability of k-ε model in Kolmogorov flow
20
作者 Jiashuo GUO Le FANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期165-184,共20页
The Reynolds-averaged Navier-Stokes(RANS)technique enables critical engineering predictions and is widely adopted.However,since this iterative computation relies on the fixed-point iteration,it may converge to unexpec... The Reynolds-averaged Navier-Stokes(RANS)technique enables critical engineering predictions and is widely adopted.However,since this iterative computation relies on the fixed-point iteration,it may converge to unexpected non-physical phase points in practice.We conduct an analysis on the phase-space characteristics and the fixed-point theory underlying the k-ε turbulence model,and employ the classical Kolmogorov flow as a framework,leveraging its direct numerical simulation(DNS)data to construct a one-dimensional(1D)system under periodic/fixed boundary conditions.The RANS results demonstrate that under periodic boundary conditions,the k-ε model exhibits only a unique trivial fixed point,with asymptotes capturing the phase portraits.The stability of this trivial fixed point is determined by a mathematically derived stability phase diagram,indicating the fact that the k-ε model will never converge to correct values under periodic conditions.In contrast,under fixed boundary conditions,the model can yield a stable non-trivial fixed point.The evolutionary mechanisms and their relationship with boundary condition settings systematically explain the inherent limitations of the k-ε model,i.e.,its deficiency in computing the flow field under periodic boundary conditions and sensitivity to boundary-value specifications under fixed boundary conditions.These conclusions are finally validated with the open-source code OpenFOAM. 展开更多
关键词 k-εmodel Kolmogorov flow INSTABILITY turbulence model
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部