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Global open source and international standards promote the inclusive development of large models
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作者 Lin Yonghua 《China Standardization》 2025年第5期25-25,共1页
In the era of AI,especially large models,the importance of open source has become increasingly prominent.First,open source allows innovation to avoid starting from scratch.Through iterative innovation,it promotes tech... In the era of AI,especially large models,the importance of open source has become increasingly prominent.First,open source allows innovation to avoid starting from scratch.Through iterative innovation,it promotes technical exchanges and learning globally.Second,resources required for large model R&D are difficult for a single institution to obtain.The evaluation of general large models also requires the participation of experts from various industries.Third,without open source collaboration,it is difficult to form a unified upper-layer software ecosystem.Therefore,open source has become an important cooperation mechanism to promote the development of AI and large models.There are two cases to illustrate how open source and international standards interact with each other. 展开更多
关键词 open source large model international standards inclusive development iterative innovationit large modelsthe evaluation general large models large models
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Assessment of Indices of Temperature Extremes Simulated by Multiple CMIP5 Models over China 被引量:18
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作者 DONG Siyan XU Ying +1 位作者 ZHOU Botao SHI Ying 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第8期1077-1091,共15页
Given that climate extremes in China might have serious regional and global consequences, an increasing number of studies are examining temperature extremes in China using the Coupled Model Intercomparison Project Pha... Given that climate extremes in China might have serious regional and global consequences, an increasing number of studies are examining temperature extremes in China using the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. This paper investigates recent changes in temperature extremes in China using 25 state-of-the-art global climate models participating in CMIP5. Thirteen indices that represent extreme temperature events were chosen and derived by daily maximum and minimum temperatures, including those representing the intensity (absolute indices and threshold indices), duration (duration indices), and frequency (percentile indices) of extreme temperature. The overall performance of each model is summarized by a "portrait" diagram based on relative root-mean-square error, which is the RMSE relative to the median RMSE of all models, revealing the multi-model ensemble simulation to be better than individual model for most indices. Compared with observations, the models are able to capture the main features of the spatial distribution of extreme temperature during 1986-2005. Overall, the CMIP5 models are able to depict the observed indices well, and the spatial structure of the ensemble result is better for threshold indices than frequency indices. The spread amongst the CMIP5 models in different subregions for intensity indices is small and the median CMIP5 is close to observations; however, for the duration and frequency indices there can be wide disagreement regarding the change between models and observations in some regions. The model ensemble also performs well in reproducing the observational trend of temperature extremes. All absolute indices increase over China during 1961-2005. 展开更多
关键词 temperature extremes China CMIP5 model evaluation
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Greenland Ice Sheet Contribution to Future Global Sea Level Rise based on CMIP5 Models 被引量:6
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作者 YAN Qing WANG Huijun +1 位作者 Ola M.JOHANNESSEN ZHANG Zhongshi 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第1期8-16,共9页
Sea level rise (SLR) is one of the major socioeconomic risks associated with global warming. Mass losses from the Greenland ice sheet (GrIS) will be partially responsible for future SLR, although there are large u... Sea level rise (SLR) is one of the major socioeconomic risks associated with global warming. Mass losses from the Greenland ice sheet (GrIS) will be partially responsible for future SLR, although there are large uncertainties in modeled climate and ice sheet behavior. We used the ice sheet model SICOPOLIS (Simulation COde for POLythermal Ice Sheets) driven by climate projections from 20 models in the fifth phase of the Coupled Model Intercomparison Project (CMIP5) to estimate the GrlS contribution to global SLR. Based on the outputs of the 20 models, it is estimated that the GrIS will contribute 0-16 (0-27) cm to global SLR by 2100 under the Representative Concentration Pathways (RCP) 4.5 (RCP 8.5) scenarios. The projected SLR increases further to 7-22 (7-33) cm with 2~basal sliding included. In response to the results of the multimodel ensemble mean, the ice sheet model projects a global SLR of 3 cm and 7 cm (10 cm and 13 cm with 2~basal sliding) under the RCP 4.5 and RCP 8.5 scenarios, respectively. In addition, our results suggest that the uncertainty in future sea level projection caused by the large spread in climate projections could be reduced with model-evaluation and the selective use of model outputs. 展开更多
关键词 sea level rise Greenland ice sheet ice sheet modeling model evaluation
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Representation of the Arctic Oscillation in the CMIP5 Models 被引量:5
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作者 ZUO Jin-Qing LI Wei-Jing REN Hong-Li 《Advances in Climate Change Research》 SCIE 2013年第4期242-249,共8页
The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are... The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are evaluated.Spectral analysis of the monthly AO index indicates that 23 out of the 26 CMIP5 models exhibit no statistically significant spectral peak in the historical experiment,as seen in the observations.These models are able to reproduce the AO pattern in the sea level pressure anomaly field during boreal winter,but the intensity of the AO pattern tends to be overestimated in all the models.The zonal-mean zonal wind anomalies associated with the AO is dominated by a meridional dipole in the mid-high latitudes of the Northern Hemisphere during boreal winter,which is well reproduced by only a few models.Most models show significant biases in both strength and location of the dipole compared to the observation.In considering the temporal variability as well as spatial structures in both horizontal and vertical directions,the MPI-ESM-P model reproduces an AO pattern that resembles the observation the best. 展开更多
关键词 Arctic Oscillation model evaluation coupled climate model CMIP5
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Assessing the Performance of CMIP6 Models in Simulating Droughts across Global Drylands 被引量:2
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作者 Xiaojing YU Lixia ZHANG +1 位作者 Tianjun ZHOU Jianghua ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期193-208,共16页
Both the attribution of historical change and future projections of droughts rely heavily on climate modeling. However,reasonable drought simulations have remained a challenge, and the related performances of the curr... Both the attribution of historical change and future projections of droughts rely heavily on climate modeling. However,reasonable drought simulations have remained a challenge, and the related performances of the current state-of-the-art Coupled Model Intercomparison Project phase 6(CMIP6) models remain unknown. Here, both the strengths and weaknesses of CMIP6 models in simulating droughts and corresponding hydrothermal conditions in drylands are assessed.While the general patterns of simulated meteorological elements in drylands resemble the observations, the annual precipitation is overestimated by ~33%(with a model spread of 2.3%–77.2%), along with an underestimation of potential evapotranspiration(PET) by ~32%(17.5%–47.2%). The water deficit condition, measured by the difference between precipitation and PET, is 50%(29.1%–71.7%) weaker than observations. The CMIP6 models show weaknesses in capturing the climate mean drought characteristics in drylands, particularly with the occurrence and duration largely underestimated in the hyperarid Afro-Asian areas. Nonetheless, the drought-associated meteorological anomalies, including reduced precipitation, warmer temperatures, higher evaporative demand, and increased water deficit conditions, are reasonably reproduced. The simulated magnitude of precipitation(water deficit) associated with dryland droughts is overestimated by 28%(24%) compared to observations. The observed increasing trends in drought fractional area,occurrence, and corresponding meteorological anomalies during 1980–2014 are reasonably reproduced. Still, the increase in drought characteristics, associated precipitation and water deficit are obviously underestimated after the late 1990s,especially for mild and moderate droughts, indicative of a weaker response of dryland drought changes to global warming in CMIP6 models. Our results suggest that it is imperative to employ bias correction approaches in drought-related studies over drylands by using CMIP6 outputs. 展开更多
关键词 DROUGHTS hydrothermal conditions DRYLANDS CMIP6 model evaluation
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Evaluation of Arctic Sea Ice Drift and its Relationship with Near-surface Wind and Ocean Current in Nine CMIP6 Models from China 被引量:3
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作者 Xiaoyong YU Chengyan LIU +3 位作者 Xiaocun WANG Jian CAO Jihai DONG Yu LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第6期903-926,共24页
The simulated Arctic sea ice drift and its relationship with the near-surface wind and surface ocean current during 1979-2014 in nine models from China that participated in the sixth phase of the Coupled Model Interco... The simulated Arctic sea ice drift and its relationship with the near-surface wind and surface ocean current during 1979-2014 in nine models from China that participated in the sixth phase of the Coupled Model Intercomparison Project(CMIP6)are examined by comparison with observational and reanalysis datasets.Most of the models reasonably represent the Beaufort Gyre(BG)and Transpolar Drift Stream(TDS)in the spatial patterns of their long-term mean sea ice drift,while the detailed location,extent,and strength of the BG and TDS vary among the models.About two-thirds of the models agree with the observation/reanalysis in the sense that the sea ice drift pattern is consistent with the near-surface wind pattern.About the same proportion of models shows that the sea ice drift pattern is consistent with the surface ocean current pattern.In the observation/reanalysis,however,the sea ice drift pattern does not match well with the surface ocean current pattern.All nine models missed the observational widespread sea ice drift speed acceleration across the Arctic.For the Arctic basin-wide spatial average,five of the nine models overestimate the Arctic long-term(1979-2014)mean sea ice drift speed in all months.Only FGOALS-g3 captures a significant sea ice drift speed increase from 1979 to 2014 both in spring and autumn.The increases are weaker than those in the observation.This evaluation helps assess the performance of the Arctic sea ice drift simulations in these CMIP6 models from China. 展开更多
关键词 Arctic sea ice sea ice drift CMIP6 model evaluation
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Evaluation of direct intramural injection to the bladder wall as a method for developing orthotopic tumor models 被引量:3
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作者 Masoud Bitaraf Samad Muhammadnejad +4 位作者 Ashkan Azimzadeh Saman Behboodi Tanourlouee Erfan Amini Masoumeh Majidi Zolbin Abdol-Mohammad Kajbafzadeh 《Animal Models and Experimental Medicine》 CAS CSCD 2022年第6期575-581,共7页
Background:Bladder cancer poses a great burden on society and its high rate of recurrence and treatment failure necessitates use of appropriate animal models to study its pathogenesis and test novel treatments.Orthoto... Background:Bladder cancer poses a great burden on society and its high rate of recurrence and treatment failure necessitates use of appropriate animal models to study its pathogenesis and test novel treatments.Orthotopic models are superior to other types since they provide a normal microenvironment.Four methods are described for developing bladder cancer models inside the animal’s bladder.Direct intramural injection is one of these methods and is widely used.However,its efficacy in model development has not yet been studied.We aimed to evaluate the efficacy and success rate of the direct intramural injection method of developing an orthotopic model for the study of bladder cancer.Method:Tumor cell lines were prepared in four microtubes.Aliquots of 200×10^(3) cells were injected through a 27 gauge needle into the ventral wall of the bladders of 4male and 4 female BALB/c mice following a midline 1 cm laparotomy incision.In addition,1 million cells from each microtube were injected into the flanks of control mice.To prevent infection and alleviate pain,5 mg/kg enrofloxacin and 2.5 mg/kg flunixin meglumine,respectively,were injected subcutaneously.Results:Tumors formed in all mice,resulting in 100% take rate and zero post-operation mortality.Surgery time was≤15 min per mouse.In two mice,tumors were found in the peritoneal space as well.Conclusion:Direct intramural injection is a rapid,reliable,and reproducible method for developing orthotopic models of bladder cancer.It can be done on both male and female mice and only requires readily available surgical tools.However,needle track can result in cell spillage and peritoneal tumors. 展开更多
关键词 animal model bladder cancer bladder wall injection model evaluation orthotopic model
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Evaluation of CMIP5 Climate Models in Simulating 1979–2005 Oceanic Latent Heat Flux over the Pacific 被引量:1
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作者 CAO Ning REN Baohua ZHENG Jianqiu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第12期1603-1616,共14页
The climatological mean state, seasonal variation and long-term upward trend of 1979-2005 latent heat flux (LHF) in historical runs of 14 coupled general circulation models from CMIP5 (Coupled Model Intercomparison... The climatological mean state, seasonal variation and long-term upward trend of 1979-2005 latent heat flux (LHF) in historical runs of 14 coupled general circulation models from CMIP5 (Coupled Model Intercomparison Project Phase 5) are evaluated against OAFlux (Objectively Analyzed air-sea Fluxes) data. Inter-model diversity of these models in simulating the annual mean climatological LHF is discussed. Results show that the models can capture the climatological LHF fairly well, but the amplitudes are generally overestimated. Model-simulated seasonal variations of LHF match well with observations with overestimated amplitudes. The possible origins of these biases are wind speed biases in the CMIP5 models. Inter-model diversity analysis shows that the overall stronger or weaker LHF over the tropical and subtropical Pacific region, and the meridional variability of LHF, are the two most notable diversities of the CMIP5 models. Regression analysis indicates that the inter-model diversity may come from the diversity of simulated SST and near-surface atmospheric specific humidity. Comparing the observed long-term upward trend, the trends of LHF and wind speed are largely underestimated, while trends of SST and air specific humidity are grossly overestimated, which may be the origins of the model biases in reproducing the trend of LHF. 展开更多
关键词 model evaluation CLIMATOLOGY TREND latent heat flux CMIP5
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An evaluation of the simulations of the Arctic Intermediate Water in climate models and reanalyses 被引量:1
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作者 LI Xiang SU Jie ZHAO Jinping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第12期1-14,共14页
The simulations of the Arctic Intermediate Water in four datasets of climate models and reanalyses, CCSM3, CCSM4, SODA and GLORYS, are analyzed and evaluated. The climatological core temperatures and depths in both CC... The simulations of the Arctic Intermediate Water in four datasets of climate models and reanalyses, CCSM3, CCSM4, SODA and GLORYS, are analyzed and evaluated. The climatological core temperatures and depths in both CCSM models exhibit deviations over 0.5°C and 200 m from the PHC. SODA reanalysis reproduces relatively reasonable spatial patterns of core temperature and depth, while GLORYS, another reanalysis, shows a remarkable cooling and deepening drift compared with the result at the beginning of the dataset especially in the Eurasian Basin (about 2°C). The heat contents at the depth of intermediate water in the CCSM models are overestimated with large positive errors nearly twice of that in the PHC. To the contrary, the GLORYS in 2009 show a negative error with a similar magnitude, which means the characteristic of the water mass is totally lost. The circulations in the two reanalyses at the depth of intermediate water are more energetic and realistic than those in the CCSMs, which is attributed to the horizontal eddy-permitting reso-lution. The velocity fields and the transports in the Fram Strait are also investigated. The necessity of finer horizontal resolution is concluded again. The northward volume transports are much larger in the two re-analyses, although they are still weak comparing with mooring observations. Finally, an investigation of the impact of assimilation is done with an evidence of the heat input from assimilation. It is thought to be a reason for the good performance in the SODA, while the GLORYS drifts dramatically without assimilation data in the Arctic Ocean. 展开更多
关键词 Arctic Intermediate Water model evaluation Arctic modeling impact of data assimilation
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Comparative Analysis of Four Stem Taper Models for Quercus glauca in Mount Halla,Jeju Island,South Korea 被引量:1
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作者 LUMBRES Roscinto Ian Canicosa LEE Young Jin +6 位作者 CHOI Hyung Soon KIM Sung Yong JANG Mi Na ABINO Azyleah Caizares SEO Yeon Ok KIM Chan Soo PARK Jung Hwan 《Journal of Mountain Science》 SCIE CSCD 2014年第2期442-448,共7页
This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using fo... This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using four statistical criteria: Fit index (FI), root mean square error (RMSE), bias (),and absolute mean difference (AMD). Results showed that the Kozak02stem taper equation provided the best FI(0.9847), RMSE(1.5745),(-0.0030 cm) and AMD (1.0990 cm) whileMax and Burkhart model had the poorest performance among the four stem taper models based on the four evaluation statistics (FI : 0.9793,RMSE : 1.8272, : 0.3040 cm and AMD : 1.3060 cm). These stem taper equations can serve as a useful tool for forest managers in estimating the diameter outside bark at any given height, merchantable stem volumes and total stem volumesof the standing trees of Quercusglaucain theGotjawal forests located in Mount Halla, Jeju Island, South Korea. 展开更多
关键词 MountHalla Merchantable stem volume Diameter outside bark Kozak model Model evaluation
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Limiting stand density and basal area projection models for even-aged Tecomella undulata plantations in a hot arid region of India
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作者 Vindhya Prasad Tewari 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期13-18,I0001,共7页
This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging... This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging to the path invariant algebraic difference form of a non-linear growth function, were also tested and compared. These models can be used to predict future basal area as a function of stand variables like dominant height and stem number per hectare and are necessary for reviewing different silvicultural treatment options. Data from 22 sample plots were used for modelling. An all possible growth intervals data structure was used. Both, qualitative and quantitative criteria were used to compare alternative models. The Akaike's information criteria differ- ence statistic was used to analyze the predictive ability of the models. Results show that the model proposed by Hui and Gadow performed best and hence this model is recommended for use in predicting basal area development in 12 undulata plantations in the study area. The data used were not from thinned stands, and hence the models may be less accurate when used for predictions when natural mortality is very significant. 展开更多
关键词 model evaluation path invariant algebraic difference form growth function potential density qualitative and quantitative criteria RAJASTHAN
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Ecological Evaluation Models for Environmental Engineering in Taiwan
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作者 Chun-Pin Chang 《Journal of Environmental Science and Engineering》 2010年第1期70-76,共7页
This study is aimed to investigate and analyze the ecological technology around ecological environment resources of engineering in Taiwan. In Taiwan, the natural and artificial material applied in the ecological techn... This study is aimed to investigate and analyze the ecological technology around ecological environment resources of engineering in Taiwan. In Taiwan, the natural and artificial material applied in the ecological technology in internal currently, usually lack of evaluation for applicative conditions. Hence, this study carried on the whole research and identifications to draft the eco-materials of ecological technology. The evaluation models of applied materials for ecological technology were proposed. The quantitative score were obtained by expert's person evaluation. Three models were proposed to quantify the effects of applied materials on the ecological environment. The statistical procedures were adopted to compare the performance of these materials for ecological technology. The results indicated that the comparison of applied materials can be treated by quantitative analysis. For the further analysis, more evaluated data from expert's experience need to be collected then the bias of person subject can be reduced. In addition to reach the benefits in the respects of ecosystem, society, economy and function, also practice the comprehensive effects in ecological technology. 展开更多
关键词 Ecological materials sustainable function evaluation models quantitative analysis life cycle assessment.
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Development and Innovation of College English Curriculum Evaluation Models
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作者 Guangfeng Zhao 《International Journal of Technology Management》 2013年第12期125-127,共3页
Teaching evaluation is an important and essential part of teaching, is an important means of detecting teaching effect. The traditional way of teaching evaluation only concerned with results of student learning, which... Teaching evaluation is an important and essential part of teaching, is an important means of detecting teaching effect. The traditional way of teaching evaluation only concerned with results of student learning, which is not conducive to reforms of English teaching methods and content. Our school s implemented English curriculum evaluation method combining formative assessment and summative assessment, which reflects the times, openness and flexibility of English teaching, but help to improve the overall quality of students, greatly promoting the reform of English teaching and development. 展开更多
关键词 College English CURRICULUM Evaluation models.
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Evaluation of Some Stem Taper Models for Camellia japonica in Mount Halla, Korea
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作者 Sung Cheol JUNG Yeon Ok SEO +1 位作者 Hyun Kyu WON Roscinto Ian C.LUMBRES 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1395-1402,共8页
This study was conducted to evaluate the performance of the four stem taper models on Camellia japonica in Jeju Island, Korea using fit statistics and lack-of-fit statistics. The five statistical criteria that were us... This study was conducted to evaluate the performance of the four stem taper models on Camellia japonica in Jeju Island, Korea using fit statistics and lack-of-fit statistics. The five statistical criteria that were used in this study were standard error of estimate(SEE), mean bias( E), absolute mean difference(AMD), coefficient of determination(R2), and root mean square error(RMSE). Results showed that the Kozak model 02 stem taper had the best performance in all fit statistics(SEE: 3.4708, E : 0.0040 cm, AMD : 0.9060 cm, R2 : 0.9870, and RMSE : 1.2545). On the other hand, Max and Burkhart stem taper model had the poorest performance in each statistical criterion(SEE: 4.2121, E : 0.2520 cm, AMD : 1.1300 cm, R2 : 0.9805, and RMSE: 1.5317). For the lack-of-fit statistics, the Kozak model 02 also provided the best performance having the best AMD in most of the relative height classes for diameter outside bark prediction and in most of the DBH classes for total volume prediction while Max and Burkhart had the poorest performance. These stem taper equations could help forest managers to better estimate the diameter outside bark at any given height, merchantable stem volumes and total stem volumes of the standing trees of Camellia japonica in the forests of Jeju Island, Korea. 展开更多
关键词 Mount Halla Stem volume Diameter outside bark Kozak model Model evaluation
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Research Progress of Evaluation Models of Cosmetic Anti-Allergy Safety
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作者 Cai Yiwen Liu Yuan +1 位作者 Song Chuang Li Huiqiong 《China Detergent & Cosmetics》 2021年第2期60-68,共9页
YiwenAbstractThe aim of this study was to explore the mechanism of skin allergic reactions,and the role of skin allergic mediators in different types of allergic reactions.Further,we reviewed and classified anti-aller... YiwenAbstractThe aim of this study was to explore the mechanism of skin allergic reactions,and the role of skin allergic mediators in different types of allergic reactions.Further,we reviewed and classified anti-allergic safety evaluation models of cosmetics based on skin allergic media.In addition,the study explored in vitro experiments,cell experiments and animal experiments performed using anti-allergic safety evaluation model.The findings of this study provide information on the importance of anti-allergic safety evaluation models in cosmetics industry,and guides on selection of anti-allergic raw materials.Moreover,the findings of this study provide a basis for further research on development of mild cosmetics. 展开更多
关键词 COSMETICS ALLERGY anti-allergy safety evaluation model
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Evaluation of the Eta Simulations Nested in Three Global Climate Models
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作者 Sin Chan Chou André Lyra +13 位作者 Caroline Mourao Claudine Dereczynski Isabel Pilotto Jorge Gomes Josiane Bustamante Priscila Tavares Adan Silva Daniela Rodrigues Diego Campos Diego Chagas Gustavo Sueiro Gracielle Siqueira Paulo Nobre José Marengo 《American Journal of Climate Change》 2014年第5期438-454,共17页
To provide long-term simulations of climate change at higher resolution, Regional Climate Models (RCMs) are nested in global climate models (GCMs). The objective of this work is to evaluate the Eta RCM simulations dri... To provide long-term simulations of climate change at higher resolution, Regional Climate Models (RCMs) are nested in global climate models (GCMs). The objective of this work is to evaluate the Eta RCM simulations driven by three global models, the HadGEM2-ES, BESM, and MIROC5, for the present period, 1961-1990. The RCM domain covers South America, Central America, and Caribbean. These simulations will be used for assessment of climate change projections in the region. Maximum temperatures are generally underestimated in the domain, in particular by MIROC5 driven simulations, in summer and winter seasons. Larger spread among the simulations was found in the minimum temperatures, which showed mixed signs of errors. The spatial correlations of temperature simulations against the CRU observations show better agreement for the MIROC5 driven simulations. The nested simulations underestimate precipitation in large areas over the continent in austral summer, whereas in winter overestimate occurs in southern Amazonia, and underestimate in southern Brazil and eastern coast of Northeast Brazil. The annual cycle of the near-surface temperature is underestimated in all model simulations, in all regions in Brazil, and in most of the year. The temperature and precipitation frequency distributions reveal that the RCM and GCM simulations contain more extreme values than the CRU observations. Evaluations of the climatic extreme indicators show that in general hot days, warm nights, and heat waves are increasing in the period, in agreement with observations. The Eta simulations driven by HadGEM2-ES show wet trends in the period, whereas the Eta driven by BESM and by MIROC5 show trends for drier conditions. 展开更多
关键词 South America Climate Downscaling Model Evaluation Climatic Extreme Indicators Eta Model
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A hybrid coupled model for the tropical Pacific constructed by integrating ROMS with a statistical atmospheric model 被引量:2
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作者 Rong-Hua ZHANG Wenzhe ZHANG +4 位作者 Yang YU Yinnan LI Feng TIAN Chuan GAO Hongna WANG 《Journal of Oceanology and Limnology》 2025年第4期1037-1055,共19页
Numerical models are crucial for quantifying the ocean-atmosphere interactions associated with the El Niño-Southern Oscillation(ENSO)phenomenon in the tropical Pacific.Current coupled models often exhibit signifi... Numerical models are crucial for quantifying the ocean-atmosphere interactions associated with the El Niño-Southern Oscillation(ENSO)phenomenon in the tropical Pacific.Current coupled models often exhibit significant biases and inter-model differences in simulating ENSO,underscoring the need for alternative modeling approaches.The Regional Ocean Modeling System(ROMS)is a sophisticated ocean model widely used for regional studies and has been coupled with various atmospheric models.However,its application in simulating ENSO processes on a basin scale in the tropical Pacific has not been explored.For the first time,this study presents the development of a basin-scale hybrid coupled model(HCM)for the tropical Pacific,integrating ROMS with a statistical atmospheric model that captures the interannual relationships between sea surface temperature(SST)and wind stress anomalies.The HCM is evaluated for its capability to simulate the annual mean,seasonal,and interannual variations of the oceanic state in the tropical Pacific.Results demonstrate that the model effectively reproduces the ENSO cycle,with a dominant oscillation period of approximately two years.The ROMS-based HCM developed here offers an efficient and robust tool for investigating climate variability in the tropical Pacific. 展开更多
关键词 Regional Ocean Modeling System(ROMS) statistical atmospheric model hybrid coupled model El Niño-Southern Oscillation(ENSO) model evaluation tropical Pacific
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Evaluating vector winds over eastern China in 2022 predicted by the CMA-MESO model and ECMWF forecast 被引量:1
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作者 Fang Huang Mingjian Zeng +4 位作者 Zhongfeng Xu Boni Wang Ming Sun Hangcheng Ge Shoukang Wu 《Atmospheric and Oceanic Science Letters》 2025年第4期41-47,共7页
Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the eva... Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the evaluation of numerical weather prediction models.In this study,the authors treat vector winds as a whole by employing a vector field evaluation method,and evaluate the mesoscale model of the China Meteorological Administration(CMA-MESO)and ECMWF forecast,with reference to ERA5 reanalysis,in terms of multiple aspects of vector winds over eastern China in 2022.The results show that the ECMWF forecast is superior to CMA-MESO in predicting the spatial distribution and intensity of 10-m vector winds.Both models overestimate the wind speed in East China,and CMA-MESO overestimates the wind speed to a greater extent.The forecasting skill of the vector wind field in both models decreases with increasing lead time.The forecasting skill of CMA-MESO fluctuates more and decreases faster than that of the ECMWF forecast.There is a significant negative correlation between the model vector wind forecasting skill and terrain height.This study provides a scientific evaluation of the local application of vector wind forecasts of the CMA-MESO model and ECMWF forecast. 展开更多
关键词 Model evaluation Vector winds CMA-MESO ECMWF Forecasting skill
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Mining-induced fracture network reconstruction and anisotropic mining-enhanced permeability evaluation using fractal theory
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作者 Zeyu Zhu Jing Xie +5 位作者 Yingxu Zhang Yuze Du Li Ren Ting Ai Bengao Yang Mingzhong Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2256-2275,共20页
In the concurrent extraction of coal and gas,the quantitative assessment of evolving characteristics in mining-induced fracture networks and mining-enhanced permeability within coal seams serves as the cornerstone for... In the concurrent extraction of coal and gas,the quantitative assessment of evolving characteristics in mining-induced fracture networks and mining-enhanced permeability within coal seams serves as the cornerstone for effective gas extraction.However,representing mining-induced fracture networks from a three-dimensional(3D)sight and developing a comprehensive model to evaluate the anisotropic mining-enhanced permeability characteristics still pose significant challenges.In this investigation,a field experiment was undertaken to systematically monitor the evolution of borehole fractures in the coal mass ahead of the mining face at the Pingdingshan Coal Mining Group in China.Using the testing data of borehole fracture,the mining-induced fracture network at varying distances from the mining face was reconstructed through a statistical reconstruction method.Additionally,utilizing fractal theory,a model for the permeability enhancement rate(PER)induced by mining was established.This model was employed to quantitatively depict the anisotropic evolution patterns of PER as the mining face advanced.The research conclusions are as follows:(1)The progression of the mining-induced fracture network can be classified into the stage of rapid growth,the stage of stable growth,and the stage of weak impact;(2)The PER of mining-induced fracture network exhibited a typical progression that can be characterized with slow growth,rapid growth and significant decline;(3)The anisotropic mining-enhanced permeability of the reconstructed mining-induced fracture networks were significant.The peak PER in the vertical direction of the coal seam is 6.86 times and 4446.38 times greater than the direction perpendicular to the vertical thickness and the direction parallel to the advancement of the mining face,respectively.This investigatione provides a viable approach and methodology for quantitatively assessing the anisotropic PER of fracture networks induced during mining,in the concurrent exploitation of coal and gas. 展开更多
关键词 Fracture networks reconstruction FRACTAL ANISOTROPY Permeability enhancement rate(PER) Evaluation model
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Identification and Countermeasures for China’s Oil Security Risks under the Dual Carbon Goals
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作者 Wang Nengquan 《China Oil & Gas》 2025年第3期11-21,共11页
This paper reviews the history and lessons of global oil crises while exploring the establishment of a quantitative evaluation model for oil security with Chinese characteristics.Using principal component analysis,it ... This paper reviews the history and lessons of global oil crises while exploring the establishment of a quantitative evaluation model for oil security with Chinese characteristics.Using principal component analysis,it constructs an oil security evaluation indicator system for China with two main-level indicators:foreign oil dependency and its impacts,and market intervention and security assurance. 展开更多
关键词 establishment quantitative evaluation model dual carbon goals principal component analysisit quantitative evaluation model foreign oil dependency market intervention security assurance principal component analysis oil security
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