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Similarity evaluation model for the internal defect detection of strip steel
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作者 ZHANG Yalin WANG Yaojie WANG Xuemin 《Baosteel Technical Research》 CAS 2024年第1期8-13,共6页
An internal defect meter is an instrument to detect the internal inclusion defects of cold-rolled strip steel.The detection accuracy of the equipment can be evaluated based on the similarity of the multiple detection ... An internal defect meter is an instrument to detect the internal inclusion defects of cold-rolled strip steel.The detection accuracy of the equipment can be evaluated based on the similarity of the multiple detection data obtained for the same steel coil.Based on the cosine similarity model and eigenvalue matrix model,a comprehensive evaluation method to calculate the weighted average of similarity is proposed.Results show that the new method is consistent with and can even replace artificial evaluation to realize the automatic evaluation of strip defect detection results. 展开更多
关键词 internal defect INCLUSION similarity evaluation model REPEATABILITY detection equipment strip steel
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Can We Estimate the Impacts of Fixed Links Using Current Transport Models?Experiences from Concept Evaluations of Fixed Links on E39
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作者 Trude Tørset 《Journal of Traffic and Transportation Engineering》 2024年第2期92-106,共15页
Transport analysis and impact evaluations are important input for decisions about infrastructure projects.The impacts on transport from fjord crossing tunnels or bridges are the foundation for the cost benefit analysi... Transport analysis and impact evaluations are important input for decisions about infrastructure projects.The impacts on transport from fjord crossing tunnels or bridges are the foundation for the cost benefit analysis,and also the basis for estimating the income from toll collection.Based on experiences from concept evaluations of several fixed link projects on E39,and an ongoing overall analysis,we question the results from transport analysis made by the official tools for such analysis:the RTM(regional transport model)which estimates the demand for trips below 10 km,the NTM(national transport model),for trips of 10 km or more,and the freight transport model.Both the NTM and the freight transport model are integrated in the RTM in the net assignment stage.We will demonstrate strengths and weaknesses in the transport models by showing contra intuitive or questionable results using the model as it is.The following questions arose as the initial results from the transport model were presented:Are the transport models able to capture immediate as well as long-term impacts?How would different assumptions about the monetary costs on these projects affect the forecasted demand and the cost benefit analysis?Are there other and wider ranges of impacts,if the analysis covers the total coastal highway as a whole,compared to evaluating impacts of each fixed link project individually?Do we have enough data to include transport effects of wider impacts of the fixed link projects?We had to deal with these questions in the concept evaluations carried out for the various fixed links project and in the current overall evaluation.We would like to suggest improvements in the analysis tools and emphasize requirements for knowledge about impacts of fixed links projects. 展开更多
关键词 Transport models transport analysis evaluation
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Study on the Construction and Evaluation System of Clinical Midwifery Teaching Faculty under the New Nursing Model
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作者 Ying Zhou Xiwei Zhang +2 位作者 Lijun Song Yingying Xiao Hua Zhang 《Journal of Clinical and Nursing Research》 2024年第7期35-41,共7页
Objective:To explore the impact of the construction of a clinical midwifery teaching faculty and the development of an evaluation system under the new nursing model on the current teaching quality.Methods:From July 20... Objective:To explore the impact of the construction of a clinical midwifery teaching faculty and the development of an evaluation system under the new nursing model on the current teaching quality.Methods:From July 2022 to March 2023,10 clinical teaching teachers and 20 midwifery interns from Beijing Anzhen Hospital affiliated with Capital Medical University were selected as the subjects of this study.The clinical teaching teachers and midwifery interns were divided into an observation group and a control group,with each group including 5 clinical teaching teachers and 10 midwifery interns.The observation group received daily management and evaluation under the new nursing model,while the control group received management and evaluation under the traditional nursing model.The teaching quality evaluation of clinical midwifery teaching teachers by midwifery interns,the exit exam scores of midwifery interns,and the scores of clinical teaching teachers’internship lectures and teaching rounds were compared between the two groups.Results:In the observation group,the scores for teaching attitude,teaching skills,and teaching management in the teaching quality evaluation of clinical midwifery teaching teachers were higher than those in the control group.The professional theory scores(91.28±3.64)and overall nursing comprehensive scores(92.56±4.38)of midwifery interns in the observation group were higher than those of midwifery interns in the control group(81.58±2.27 and 80.29±3.33,respectively).The scores for internship lectures(89.32±4.15)and teaching rounds(90.64±5.52)in the observation group were also significantly higher than those in the control group(80.46±3.28 and 81.24±4.38,respectively),and the differences were statistically significant(P<0.05).Conclusion:The management of the clinical midwifery teaching faculty under the new nursing model effectively improved the quality of clinical teaching.It significantly enhanced the teaching effectiveness of clinical teaching teachers and the proficiency of midwifery interns in clinical operations,making it worthy of promotion and use. 展开更多
关键词 Clinical teaching Teaching faculty New nursing model evaluation system
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Contribution of the MERISE-Type Conceptual Data Model to the Construction of Monitoring and Evaluation Indicators of the Effectiveness of Training in Relation to the Needs of the Labor Market in the Republic of Congo
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作者 Roch Corneille Ngoubou Basile Guy Richard Bossoto Régis Babindamana 《Open Journal of Applied Sciences》 2024年第8期2187-2200,共14页
This study proposes the use of the MERISE conceptual data model to create indicators for monitoring and evaluating the effectiveness of vocational training in the Republic of Congo. The importance of MERISE for struct... This study proposes the use of the MERISE conceptual data model to create indicators for monitoring and evaluating the effectiveness of vocational training in the Republic of Congo. The importance of MERISE for structuring and analyzing data is underlined, as it enables the measurement of the adequacy between training and the needs of the labor market. The innovation of the study lies in the adaptation of the MERISE model to the local context, the development of innovative indicators, and the integration of a participatory approach including all relevant stakeholders. Contextual adaptation and local innovation: The study suggests adapting MERISE to the specific context of the Republic of Congo, considering the local particularities of the labor market. Development of innovative indicators and new measurement tools: It proposes creating indicators to assess skills matching and employer satisfaction, which are crucial for evaluating the effectiveness of vocational training. Participatory approach and inclusion of stakeholders: The study emphasizes actively involving training centers, employers, and recruitment agencies in the evaluation process. This participatory approach ensures that the perspectives of all stakeholders are considered, leading to more relevant and practical outcomes. Using the MERISE model allows for: • Rigorous data structuring, organization, and standardization: Clearly defining entities and relationships facilitates data organization and standardization, crucial for effective data analysis. • Facilitation of monitoring, analysis, and relevant indicators: Developing both quantitative and qualitative indicators helps measure the effectiveness of training in relation to the labor market, allowing for a comprehensive evaluation. • Improved communication and common language: By providing a common language for different stakeholders, MERISE enhances communication and collaboration, ensuring that all parties have a shared understanding. The study’s approach and contribution to existing research lie in: • Structured theoretical and practical framework and holistic approach: The study offers a structured framework for data collection and analysis, covering both quantitative and qualitative aspects, thus providing a comprehensive view of the training system. • Reproducible methodology and international comparison: The proposed methodology can be replicated in other contexts, facilitating international comparison and the adoption of best practices. • Extension of knowledge and new perspective: By integrating a participatory approach and developing indicators adapted to local needs, the study extends existing research and offers new perspectives on vocational training evaluation. 展开更多
关键词 MERISE Conceptual Data model (MCD) Monitoring Indicators evaluation of Training Effectiveness Training-Employment Adequacy Labor Market Information Systems Analysis Adjustment of Training Programs EMPLOYABILITY Professional Skills
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Shale gas production evaluation framework based on data-driven models 被引量:3
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作者 You-Wei He Zhi-Yue He +3 位作者 Yong Tang Ying-Jie Xu Ji-Chang Long Kamy Sepehrnoori 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1659-1675,共17页
Increasing the production and utilization of shale gas is of great significance for building a clean and low-carbon energy system.Sharp decline of gas production has been widely observed in shale gas reservoirs.How to... Increasing the production and utilization of shale gas is of great significance for building a clean and low-carbon energy system.Sharp decline of gas production has been widely observed in shale gas reservoirs.How to forecast shale gas production is still challenging due to complex fracture networks,dynamic fracture properties,frac hits,complicated multiphase flow,and multi-scale flow as well as data quality and uncertainty.This work develops an integrated framework for evaluating shale gas well production based on data-driven models.Firstly,a comprehensive dominated-factor system has been established,including geological,drilling,fracturing,and production factors.Data processing and visualization are required to ensure data quality and determine final data set.A shale gas production evaluation model is developed to evaluate shale gas production levels.Finally,the random forest algorithm is used to forecast shale gas production.The prediction accuracy of shale gas production level is higher than 95%based on the shale gas reservoirs in China.Forty-one wells are randomly selected to predict cumulative gas production using the optimal regression model.The proposed shale gas production evaluation frame-work overcomes too many assumptions of analytical or semi-analytical models and avoids huge computation cost and poor generalization for numerical modelling. 展开更多
关键词 Shale gas Production evaluation Production prediction Data-driven models Carbon neutrality
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Evaluation of toppling rock slopes using a composite cloud model with DEMATEL–CRITIC method 被引量:3
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作者 Huan-ling Wang Xu-fei Zhao +3 位作者 Hong-jie Chen Kui Yi Wei-chau Xie Wei-ya Xu 《Water Science and Engineering》 EI CAS CSCD 2023年第3期280-288,共9页
Safety evaluation of toppling rock slopes developing in reservoir areas is crucial. To reduce the uncertainty of safety evaluation, this study developed a composite cloud model, which improved the combination weights ... Safety evaluation of toppling rock slopes developing in reservoir areas is crucial. To reduce the uncertainty of safety evaluation, this study developed a composite cloud model, which improved the combination weights of the decision-making trial and evaluation laboratory (DEMATEL) and criteria importance through intercriteria correlation (CRITIC) methods. A safety evaluation system was developed according to in situ monitoring data. The backward cloud generator was used to calculate the numerical characteristics of a cloud model of quantitative indices, and different virtual clouds were used to synthesize some clouds into a generalized one. The synthesized numerical characteristics were calculated to comprehensively evaluate the safety of toppling rock slopes. A case study of a toppling rock slope near the Huangdeng Hydropower Station in China was conducted using monitoring data collected since operation of the hydropower project began. The results indicated that the toppling rock slope was moderately safe with a low safety margin. The composite cloud model considers the fuzziness and randomness of safety evaluation and enables interchange between qualitative and quantitative knowledge. This study provides a new theoretical method for evaluating the safety of toppling rock slopes. It can aid in the predication, control, and even prevention of disasters. 展开更多
关键词 Toppling rock slope Safety evaluation Composite cloud model DEMATEL CRITIC Huangdeng Hydropower Project
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Method for Evaluating Bolt Competitive Failure Life Under Composite Excitation 被引量:1
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作者 Guangwu Yang Long Yang +3 位作者 Han Zhao Haoxu Ding Bing Yang Shoune Xiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期372-384,共13页
In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode predict... In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode prediction model and“load ratio-life prediction curve”(ξ-N curve)of the bolt competitive failure are established.Given the poor correlation of theξ-N curve,an evaluation model of the bolt competitive failure life is proposed based on Miner’s linear damage accumulation theory.Based on the force analysis of the thread surface and simulation of the bolt connection under composite excitation,a theoretical equation of the bolt competitive failure life is established to validate the model for evaluating the bolt competitive failure life.The results reveal that the proposed model can accurately predict the competitive failure life of bolts under composite excitation,and thereby,it can provide guidance to engineering applications. 展开更多
关键词 BOLT Competitive failure life evaluation model Mode prediction model Composite excitation
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Establishment and evaluation of a risk prediction model for gestational diabetes mellitus 被引量:1
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作者 Qing Lin Zhuan-Ji Fang 《World Journal of Diabetes》 SCIE 2023年第10期1541-1550,共10页
BACKGROUND Gestational diabetes mellitus(GDM)is a condition characterized by high blood sugar levels during pregnancy.The prevalence of GDM is on the rise globally,and this trend is particularly evident in China,which... BACKGROUND Gestational diabetes mellitus(GDM)is a condition characterized by high blood sugar levels during pregnancy.The prevalence of GDM is on the rise globally,and this trend is particularly evident in China,which has emerged as a significant issue impacting the well-being of expectant mothers and their fetuses.Identifying and addressing GDM in a timely manner is crucial for maintaining the health of both expectant mothers and their developing fetuses.Therefore,this study aims to establish a risk prediction model for GDM and explore the effects of serum ferritin,blood glucose,and body mass index(BMI)on the occurrence of GDM.AIM To develop a risk prediction model to analyze factors leading to GDM,and evaluate its efficiency for early prevention.METHODS The clinical data of 406 pregnant women who underwent routine prenatal examination in Fujian Maternity and Child Health Hospital from April 2020 to December 2022 were retrospectively analyzed.According to whether GDM occurred,they were divided into two groups to analyze the related factors affecting GDM.Then,according to the weight of the relevant risk factors,the training set and the verification set were divided at a ratio of 7:3.Subsequently,a risk prediction model was established using logistic regression and random forest models,and the model was evaluated and verified.RESULTS Pre-pregnancy BMI,previous history of GDM or macrosomia,hypertension,hemoglobin(Hb)level,triglyceride level,family history of diabetes,serum ferritin,and fasting blood glucose levels during early pregnancy were determined.These factors were found to have a significant impact on the development of GDM(P<0.05).According to the nomogram model’s prediction of GDM in pregnancy,the area under the curve(AUC)was determined to be 0.883[95%confidence interval(CI):0.846-0.921],and the sensitivity and specificity were 74.1%and 87.6%,respectively.The top five variables in the random forest model for predicting the occurrence of GDM were serum ferritin,fasting blood glucose in early pregnancy,pre-pregnancy BMI,Hb level and triglyceride level.The random forest model achieved an AUC of 0.950(95%CI:0.927-0.973),the sensitivity was 84.8%,and the specificity was 91.4%.The Delong test showed that the AUC value of the random forest model was higher than that of the decision tree model(P<0.05).CONCLUSION The random forest model is superior to the nomogram model in predicting the risk of GDM.This method is helpful for early diagnosis and appropriate intervention of GDM. 展开更多
关键词 Gestational diabetes mellitus Prediction model model evaluation Random forest model NOMOGRAMS Risk factor
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基于24Model-D-ISM的地铁站火灾疏散影响因素研究
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作者 孙世梅 张家严 《中国安全科学学报》 CAS CSCD 北大核心 2024年第4期153-159,共7页
为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾... 为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾人员疏散影响因素指标体系;采用算子客观赋权法(C-OWA)改进决策试验与评价实验法(DEMATEL),确定地铁站火灾人员疏散的重要影响因素;在此基础上,采用解释结构模型(ISM)分析各个因素间的层次结构及相互作用路径,构建地铁站火灾人员疏散影响因素的多级递阶结构模型。研究结果表明:疏散引导、恐慌从众行为、人员拥挤为地铁站火灾人员疏散的关键影响因素;地铁站火灾人员疏散受表层因素、中间层因素、深层因素共同作用的影响,其中,疏散教育与培训、设施维护与检查、疏散预案等因素是根源影响因素,重视根源影响因素的改善有利于从本质上预防和控制事故的发生。 展开更多
关键词 “2-4”模型(24model) 决策试验与评价实验法(DEMATEL) 解释结构模型(ISM) 地铁站 火灾疏散 影响因素
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 FUQIANG XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 evaluATION projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations
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A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China 被引量:19
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作者 YAO Yanbin LIU Dameng TANG Dazhen HUANG Wenhui TANG Shuheng CHE Yao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1253-1270,共18页
Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and meth... Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process (AHP) model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria (including reservoir physical property, storage capacity and geological characteristics), 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank (mean maximum vitrinite reflectance 〉0.5 %) coal districts in China. 展开更多
关键词 coalbed methane reservoir reservoir evaluation reservoir characterization comprehensive model Fuzzy Hierarchy Process Approach (FAHP)
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Evaluating Common Land Model Energy Fluxes Using FLUXNET Data 被引量:4
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作者 Xiangxiang ZHANG Yongjiu DAI +8 位作者 Hongzhi CUI Robert E.DICKINSON Siguang ZHU Nan WEI Binyan YAN Hua YUAN Wei SHANGGUAN Lili WANG Wenting FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1035-1046,共12页
Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the ... Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the eddy covariance measurements from 20 FLUXNET sites spanning more than 100 site-years were utilized to evaluate the performance of the Common Land Model (CoLM) over different vegetation types in various climate zones. A decomposition method was employed to separate both the observed and simulated energy fluxes, i.e., the sensible heat flux, latent heat flux, net radiation, and ground heat flux, at three timescales ranging from stepwise (30 rain) to monthly. A comparison between the simulations and observations indicated that CoLM produced satisfactory simulations of all four energy fluxes, although the different indexes did not exhibit consistent results among the different fluxes, A strong agreement between the simulations and observations was found for the seasonal cycles at the 20 sites, whereas CoLM underestimated the latent heat flux at the sites with distinct dry and wet seasons, which might be associated with its weakness in simulating soil water during the dry season. CoLM cannot explicitly simulate the midday depression of leaf gas exchange, which may explain why CoLM also has a maximum diurnal bias at noon in the summer. Of the eight selected vegetation types analyzed, CoLM performs best for evergreen broadleaf forests and worst for croplands and wetlands. 展开更多
关键词 model evaluation Common Land model FLUXNET
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Assessing the Performance of CMIP6 Models in Simulating Droughts across Global Drylands 被引量:1
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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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An attribute recognition model based on entropy weight for evaluating the quality of groundwater sources 被引量:21
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作者 CHEN Suo-zhong WANG Xiao-jing ZHAO Xiu-jun 《Journal of China University of Mining and Technology》 EI 2008年第1期72-75,共4页
In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by ... In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by Chen Q S. In the model, firstly, the author establishes the attribute space matrix and determines the weight based on Shannon entropy theory; secondly, calculates attribute measure; thirdly, evaluates that with confidence criterion and score criterion; finally, an application example is given. The results show that the water quality of the groundwater sources for the city comes up to the grade II or III standard. There is no pollution that obviously exceeds the standard and the water can meet people’s needs .The results from an evaluation of this model are in basic agreement with the observed situation and with a set pair analysis (SPA) model. 展开更多
关键词 water quality evaluation groundwater sources entropy weigh attribute recognition model
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A general evaluation system for optimal selection performance of radar clutter model
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作者 YANG Wei ZHANG Liang +2 位作者 YANG Liru ZHANG Wenpeng SHEN Qinmu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1520-1525,共6页
The optimal selection of radar clutter model is the premise of target detection,tracking,recognition,and cognitive waveform design in clutter background.Clutter characterization models are usually derived by mathemati... The optimal selection of radar clutter model is the premise of target detection,tracking,recognition,and cognitive waveform design in clutter background.Clutter characterization models are usually derived by mathematical simplification or empirical data fitting.However,the lack of standard model labels is a challenge in the optimal selection process.To solve this problem,a general three-level evaluation system for the model selection performance is proposed,including model selection accuracy index based on simulation data,fit goodness indexs based on the optimally selected model,and evaluation index based on the supporting performance to its third-party.The three-level evaluation system can more comprehensively and accurately describe the selection performance of the radar clutter model in different ways,and can be popularized and applied to the evaluation of other similar characterization model selection. 展开更多
关键词 radar clutter clutter characterization model model selection performance evaluation.
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Evaluating Parameterizations for Turbulent Fluxes over the Landfast Sea-Ice Surface in Prydz Bay, Antarctica
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作者 Fangyuan CHENG Qinghua YANG +3 位作者 Changwei LIU Bo HAN Shijie PENG Guanghua HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第10期1816-1832,共17页
It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East Antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes... It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East Antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes over the landfast seaice surface in five numerical models.The Community Noah Land Surface Model with Multi-Parameterizations Options(Noah_mp)best replicates the turbulent momentum flux,while the Beijing Climate System Model(BCC_CSM)produces the optimum sensible and latent heat fluxes.In particular,two critical issues of parameterization schemes,stability functions and roughness lengths,are investigated.Sensitivity tests indicate that roughness lengths play a decisive role in model performance.Based on the observed turbulent fluxes,roughness lengths over the landfast sea-ice surface are calculated.The results,which can provide a basis for setting up model parameters,reveal that the dynamic roughness length(z0m)increases with the increase of frictional velocity(u*)when u*≤0.4 m s^(−1) and fluctuates around 10^(−3 )m when u*>0.4 m s^(−1);thermal roughness length(z0t)is linearly related to the temperature gradient between air and sea-ice surface(ΔT)with a relation of lg(z0t)=−0.29ΔT−3.86;and the mean water vapor roughness length(z0q)in the specific humidity gradient(Δq)range ofΔq≤−0.6 g kg^(−1) is 10^(−6) m,3.5 times smaller than that in the range ofΔq˃−0.6 g kg^(−1). 展开更多
关键词 turbulent fluxes ANTARCTICA landfast sea-ice surface PARAMETERIZATION evaluating numerical models
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Evaluation of global gridded crop models in simulating sugarcane yield in China 被引量:1
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作者 Dezhen Yin Jingjing Yan +1 位作者 Fang Li Tianyuan Song 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第2期49-54,共6页
中国是全球第三大甘蔗生产国,中国甘蔗产量模拟可服务于全球食糖和乙醇的生产和贸易.全球格点作物模式CLM5-crop和LPJmL已实现对甘蔗的模拟,但它们在中国的模拟能力未知.本文评估结果表明:两个模式均严重低估了甘蔗产量,模拟均不足观测... 中国是全球第三大甘蔗生产国,中国甘蔗产量模拟可服务于全球食糖和乙醇的生产和贸易.全球格点作物模式CLM5-crop和LPJmL已实现对甘蔗的模拟,但它们在中国的模拟能力未知.本文评估结果表明:两个模式均严重低估了甘蔗产量,模拟均不足观测的1/4.CLM5-crop能有技巧地模拟产量的空间分布特征,而LPJmL不能.两个模式均不能合理模拟产量的年际变化,且低估了产量的上升趋势.模式低估甘蔗产量的部分原因是模式假设收割的是甘蔗的穗而非茎. 展开更多
关键词 全球格点作物模式 模式评估 甘蔗 产量 中国
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A Dynamic Bayesian-Based Comprehensive Trust Evaluation Model for Dispersed Computing Environment
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作者 Hongwen Hui Zhengxia Gong +1 位作者 Jianwei An Jianzhong Qi 《China Communications》 SCIE CSCD 2023年第2期278-288,共11页
Dispersed computing is a new resourcecentric computing paradigm.Due to its high degree of openness and decentralization,it is vulnerable to attacks,and security issues have become an important challenge hindering its ... Dispersed computing is a new resourcecentric computing paradigm.Due to its high degree of openness and decentralization,it is vulnerable to attacks,and security issues have become an important challenge hindering its development.The trust evaluation technology is of great significance to the reliable operation and security assurance of dispersed computing networks.In this paper,a dynamic Bayesian-based comprehensive trust evaluation model is proposed for dispersed computing environment.Specifically,in the calculation of direct trust,a logarithmic decay function and a sliding window are introduced to improve the timeliness.In the calculation of indirect trust,a random screening method based on sine function is designed,which excludes malicious nodes providing false reports and multiple malicious nodes colluding attacks.Finally,the comprehensive trust value is dynamically updated based on historical interactions,current interactions and momentary changes.Simulation experiments are introduced to verify the performance of the model.Compared with existing model,the proposed trust evaluation model performs better in terms of the detection rate of malicious nodes,the interaction success rate,and the computational cost. 展开更多
关键词 dispersed computing trust evaluation model malicious node interaction success rate detection rate
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Sorghum Yield Response to Changing Climatic Conditions in Semi-Arid Central Tanzania: Evaluating Crop Simulation Model Applicability 被引量:2
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作者 Barnabas Msongaleli Filbert Rwehumbiza +1 位作者 Siza D. Tumbo Nganga Kihupi 《Agricultural Sciences》 2014年第10期822-833,共12页
Decision Support System for Agrotechnology Transfer (DSSAT) and Agricultural Production Systems SIMulator (APSIM) were calibrated and evaluated to simulate sorghum (Sorghum Bicolor L. Moench) var. Tegemeo under curren... Decision Support System for Agrotechnology Transfer (DSSAT) and Agricultural Production Systems SIMulator (APSIM) were calibrated and evaluated to simulate sorghum (Sorghum Bicolor L. Moench) var. Tegemeo under current and future climate in central Tanzania. Simulations for both current and future periods were run assuming present technology, current varieties and current agronomy packages to investigate rain-fed sorghum yield response. Simulations by both crop models using downscaled weather data from eight General Circulation Models (GCMs) under the Coupled Model Intercomparison Project phase 5 (CMIP5) and Representative Concentration Pathway (RCP 4.5) by mid-century show a mixture of increase and decrease in median sorghum yields. Four GCMs project yields to increase by 5% - 23.0% and one GCM show a decrease by 2% - 9%. Model simulations under the remaining three GCMs give contrasting results of increase and decrease. Adjustment of crop duration to mimic the choice of growing local cultivars versus improved cultivars seems a feasible option under future climate scenarios. Our simulation results show that current open-pollinated sorghum cultivars would be resilient to projected changes in climate by 2050s but things seem better with long duration cultivars. We conclude that crop simulation models show their applicability as tools for assessing possible impacts of climate change on sorghum due to agreement in the direction of crop yield predictions in five out of eight selected GCMs under projected climate scenarios. The findings provide useful guidance and motivation to government authorities and development agencies dealing with food security issues to prioritize adaptations policies geared to ensuring increased and sustained sorghum productivity in Tanzania and elsewhere. 展开更多
关键词 YIELD Prediction CLIMATE Change ADAPTATION model evaluation
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Zoning Evaluation of Hourly Precipitation in High-resolution Regional Numerical Models over Hainan Island
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作者 冯箫 吴俞 +1 位作者 杨薇 李勋 《Journal of Tropical Meteorology》 SCIE 2023年第4期460-472,共13页
This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequen... This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequency,intensity,duration,and diurnal cycle are examined through zoning evaluation.The results show that the China Meteor-ological Administration Guangdong Rapid Update Assimilation Numerical Forecast System(CMA-GD)tends to forecast a higher occurrence of light precipitation.It underestimates the late afternoon precipitation and the occurrence of short-duration events.The China Meteorological Administration Shanghai Numerical Forecast Model System(CMA-SH9)reproduces excessive precipitation at a higher frequency and intensity throughout the island.It overestimates rainfall during the late afternoon and midnight periods.The simulated most frequent peak times of rainfall in CMA-SH9 are 0-1 hour deviations from the observed data.The China Meteorological Administration Mesoscale Weather Numerical Forecasting System(CMA-MESO)displays a similar pattern to rainfall observations but fails to replicate reasonable structure and diurnal variation of frequency-intensity.It underestimates the occurrence of long-duration events and overestimates related rainfall amounts from midnight to early morning.Notably,significant discrepancies are observed in the predictions of the three models for areas with complex terrain,such as the central,southeastern,and southwestern regions of Hainan Island. 展开更多
关键词 Hainan Island hourly precipitation regional numerical model zoning evaluation
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