This work aims to analyze the effect exerted by the initial and continuous training of secondary school teachers in France on their teaching practices.For this,we carried out a secondary analysis of data from the TALI...This work aims to analyze the effect exerted by the initial and continuous training of secondary school teachers in France on their teaching practices.For this,we carried out a secondary analysis of data from the TALIS survey(Teaching and Learning International Survey),conducted in 2013 in 34 countries,including France.In particular,we focus on practices related to the teaching methods used,classroom management,how to communicate,and the evaluative practices of teachers.In support of binary logistic regression models,we showed that the variables related to initial training play a weak role,and even exert a negative effect on certain pedagogic practices,leading to a reflection on the renovation of this training.On the other hand,our analyses highlighted the greater weight played by certain continuing education actions.展开更多
The hybrid dynamics of multi-rigid-body and multi-flexible-body system becomes the mainstream of multi-body dynamics.Currently there lacks a compact approach to model the hybrid dynamics,especially in modern machine t...The hybrid dynamics of multi-rigid-body and multi-flexible-body system becomes the mainstream of multi-body dynamics.Currently there lacks a compact approach to model the hybrid dynamics,especially in modern machine tool application,due to the difficulty of solving the hybrid equations or the limitation of current software when dealing with the hybrid dynamics.The extended transfer matrix method(E-TMM),which extends elements in three-dimensional space with higher matrixes,is proposed to simplify the modeling process of the hybrid dynamics.The E-TMM modeling approaches of 3 basic elements including 3D vibrant rigid body,joint and flexible body are studied in details.A parallel mill-turn tool spindle head unit driven by dual-linear motors is chosen as a plant to demonstrate the E-TMM modeling process.By using E-TMM,the spindle head unit is simplified as a topological network consisting of the three types of element,i.e.,3D vibrant rigid body,joint and flexible body,including 11 rigid bodies,14 joints and 1 3D-Timoshenko beam.Then the dynamic model of the system can be easily obtained by deducing the element-network by means of state vector transformation.The dynamic characteristics of the spindle head,such as natural frequencies,dynamic flexibility,etc.can be predicted by solving the obtained model.Experiment verification indicates that the E-TMM is valid with enough accuracy in the dynamic analysis of the parallel mill-turn tool spindle head.The E-TMM is capable of modeling the dynamics of machine tool structure with no requirements of deducing and solving the sophisticated differential equations.Moreover,the E-TMM provides a simple and elegant tool for hybrid dynamic analysis in future dynamic design of machine tools.展开更多
Recent development on distributed systems has shown that a variety of fairness constraints (some of which are only recently defined) play vital roles in designing self- stabilizing population protocols. Existing mod...Recent development on distributed systems has shown that a variety of fairness constraints (some of which are only recently defined) play vital roles in designing self- stabilizing population protocols. Existing model checkers are deficient in verifying the systems as only limited kinds of fair- ness are supported with limited verification efficiency. In this work, we support model checking of distributed systems in the toolkit PAT (process analysis toolkit), with a variety of fairness constraints (e.g., process-level weak/strong fairness, event-level weak/strong fairness, strong global fairness). It performs on-the-fly verification against linear temporal prop- erties. We show through empirical evaluation (on recent pop- ulation protocols as well as benchmark systems) that PAT has advantage in model checking with fairness. Previously un- known bugs have been revealed against systems which are designed to function only with strong global fairness.展开更多
For surface runoff estimation in the Soil and Water Assessment Tool(SWAT)model,the curve number(CN)procedure is commonly adopted to calculate surface runoff by dynamically updating CN values based on antecedent soil m...For surface runoff estimation in the Soil and Water Assessment Tool(SWAT)model,the curve number(CN)procedure is commonly adopted to calculate surface runoff by dynamically updating CN values based on antecedent soil moisture condition(SCSI)in field.From SWAT2005 and onward,an alternative approach has become available to apply the CN method by relating the runoff potential to daily evapotranspiration(SCSII).While improved runoff prediction with SCSII has been reported in several case studies,few investigations have been made on its influence to water quality output or on the model uncertainty associated with the SCSII method.The objectives of the research were:(1)to quantify the improvements in hydrologic and water quality predictions obtained through different surface runoff estimation techniques;and(2)to examine how model uncertainty is affected by combining different surface runoff estimation techniques within SWAT using Bayesian model averaging(BMA).Applications of BMA provide an alternative approach to investigate the nature of structural uncertainty associated with both CN methods.Results showed that SCSII and BMA associated approaches exhibit improved performance in both discharge and total NO3 predictions compared to SCSI.In addition,the application of BMA has a positive effect on finding well performed solutions in the multi-dimensional parameter space,but the predictive uncertainty is not evidently reduced or enhanced.Therefore,we recommend additional future SWAT calibration/validation research with an emphasis on the impact of SCSII on the prediction of other pollutants.展开更多
文摘This work aims to analyze the effect exerted by the initial and continuous training of secondary school teachers in France on their teaching practices.For this,we carried out a secondary analysis of data from the TALIS survey(Teaching and Learning International Survey),conducted in 2013 in 34 countries,including France.In particular,we focus on practices related to the teaching methods used,classroom management,how to communicate,and the evaluative practices of teachers.In support of binary logistic regression models,we showed that the variables related to initial training play a weak role,and even exert a negative effect on certain pedagogic practices,leading to a reflection on the renovation of this training.On the other hand,our analyses highlighted the greater weight played by certain continuing education actions.
基金supported by National Key Technology R&D Program of China (Grant No. 2006BAF01B09)the Research Fund for Doctoral Program of Higher Education of China (Grant No. 200800060010)
文摘The hybrid dynamics of multi-rigid-body and multi-flexible-body system becomes the mainstream of multi-body dynamics.Currently there lacks a compact approach to model the hybrid dynamics,especially in modern machine tool application,due to the difficulty of solving the hybrid equations or the limitation of current software when dealing with the hybrid dynamics.The extended transfer matrix method(E-TMM),which extends elements in three-dimensional space with higher matrixes,is proposed to simplify the modeling process of the hybrid dynamics.The E-TMM modeling approaches of 3 basic elements including 3D vibrant rigid body,joint and flexible body are studied in details.A parallel mill-turn tool spindle head unit driven by dual-linear motors is chosen as a plant to demonstrate the E-TMM modeling process.By using E-TMM,the spindle head unit is simplified as a topological network consisting of the three types of element,i.e.,3D vibrant rigid body,joint and flexible body,including 11 rigid bodies,14 joints and 1 3D-Timoshenko beam.Then the dynamic model of the system can be easily obtained by deducing the element-network by means of state vector transformation.The dynamic characteristics of the spindle head,such as natural frequencies,dynamic flexibility,etc.can be predicted by solving the obtained model.Experiment verification indicates that the E-TMM is valid with enough accuracy in the dynamic analysis of the parallel mill-turn tool spindle head.The E-TMM is capable of modeling the dynamics of machine tool structure with no requirements of deducing and solving the sophisticated differential equations.Moreover,the E-TMM provides a simple and elegant tool for hybrid dynamic analysis in future dynamic design of machine tools.
文摘Recent development on distributed systems has shown that a variety of fairness constraints (some of which are only recently defined) play vital roles in designing self- stabilizing population protocols. Existing model checkers are deficient in verifying the systems as only limited kinds of fair- ness are supported with limited verification efficiency. In this work, we support model checking of distributed systems in the toolkit PAT (process analysis toolkit), with a variety of fairness constraints (e.g., process-level weak/strong fairness, event-level weak/strong fairness, strong global fairness). It performs on-the-fly verification against linear temporal prop- erties. We show through empirical evaluation (on recent pop- ulation protocols as well as benchmark systems) that PAT has advantage in model checking with fairness. Previously un- known bugs have been revealed against systems which are designed to function only with strong global fairness.
基金This study was supported in part by the US DA-National Institute of Food and Agriculture grants 2007-51130-03876,2009-51130-06038the Research Program for Agricultural Science&Technology Development(Project No.PJ008566)National Academy of Agricultural Science,Rural Development Administration,Republic of Korea,and the USDA-NRCS Conservation Effects Assessment Project(CEAP)-Wildlife and Cropland components.
文摘For surface runoff estimation in the Soil and Water Assessment Tool(SWAT)model,the curve number(CN)procedure is commonly adopted to calculate surface runoff by dynamically updating CN values based on antecedent soil moisture condition(SCSI)in field.From SWAT2005 and onward,an alternative approach has become available to apply the CN method by relating the runoff potential to daily evapotranspiration(SCSII).While improved runoff prediction with SCSII has been reported in several case studies,few investigations have been made on its influence to water quality output or on the model uncertainty associated with the SCSII method.The objectives of the research were:(1)to quantify the improvements in hydrologic and water quality predictions obtained through different surface runoff estimation techniques;and(2)to examine how model uncertainty is affected by combining different surface runoff estimation techniques within SWAT using Bayesian model averaging(BMA).Applications of BMA provide an alternative approach to investigate the nature of structural uncertainty associated with both CN methods.Results showed that SCSII and BMA associated approaches exhibit improved performance in both discharge and total NO3 predictions compared to SCSI.In addition,the application of BMA has a positive effect on finding well performed solutions in the multi-dimensional parameter space,but the predictive uncertainty is not evidently reduced or enhanced.Therefore,we recommend additional future SWAT calibration/validation research with an emphasis on the impact of SCSII on the prediction of other pollutants.