The probability-based covering algorithm(PBCA) is a new algorithm based on probability distribution. It decides, by voting, the class of the tested samples on the border of the coverage area, based on the probability ...The probability-based covering algorithm(PBCA) is a new algorithm based on probability distribution. It decides, by voting, the class of the tested samples on the border of the coverage area, based on the probability of training samples. When using the original covering algorithm(CA), many tested samples that are located on the border of the coverage cannot be classified by the spherical neighborhood gained. The network structure of PBCA is a mixed structure composed of both a feed-forward network and a feedback network. By using this method of adding some heterogeneous samples and enlarging the coverage radius,it is possible to decrease the number of rejected samples and improve the rate of recognition accuracy. Relevant computer experiments indicate that the algorithm improves the study precision and achieves reasonably good results in text classification.展开更多
We propose a strategy for generating unbiased and systematically extendable training data for machine learning interatomic potentials(MLIP)for multicomponent alloys,called Automated Small SYmmetric Structure Training ...We propose a strategy for generating unbiased and systematically extendable training data for machine learning interatomic potentials(MLIP)for multicomponent alloys,called Automated Small SYmmetric Structure Training or ASSYST.Based on exploring the full space of random crystal structures with space groups,it facilitates the construction of training sets for MLIPs in an automatic way without prior knowledge of the material in question.The advantages of this approach are that only cells consisting of few atoms(≈10)are needed for the DFT training set,and the size and completeness of the data set can be systematically controlled with very few parameters.We validate that potentials fitted this way can accurately describe a wide range of binary and ternary phases,random alloys,as well as point and extended defects,that have not been part of the training set.Finally,we estimate the binary phase diagrams with good experimental agreement.We demonstrate that the overall excellent performance is not a coincidence,but a consequence of the extensive sampling in phase space of ASSYST.Overall,this means that ASSYST will enable the largely autonomous generation of highquality DFT reference data and MLIPs.展开更多
Rock-fill dykes are often damaged caused by rapid flow currents in a mountainriver. Based on the relationship between the rock size on cover layer and its incipient velocity,it is found that rock weight is directly pr...Rock-fill dykes are often damaged caused by rapid flow currents in a mountainriver. Based on the relationship between the rock size on cover layer and its incipient velocity,it is found that rock weight is directly proportional to the 6th-9th power of incipient velocity,and 50% increase of the velocity may result in about 40 times increase of the rock weight.Therefore, it is inappropriate to improve the stability of rock-fill dykes by simply increasing therock weight. Some new measures should be used to reach this purpose.展开更多
基金supported by the Fund for Philosophy and Social Science of Anhui Provincethe Fund for Human and Art Social Science of the Education Department of Anhui Province(Grant Nos.AHSKF0708D13 and 2009sk038)
文摘The probability-based covering algorithm(PBCA) is a new algorithm based on probability distribution. It decides, by voting, the class of the tested samples on the border of the coverage area, based on the probability of training samples. When using the original covering algorithm(CA), many tested samples that are located on the border of the coverage cannot be classified by the spherical neighborhood gained. The network structure of PBCA is a mixed structure composed of both a feed-forward network and a feedback network. By using this method of adding some heterogeneous samples and enlarging the coverage radius,it is possible to decrease the number of rejected samples and improve the rate of recognition accuracy. Relevant computer experiments indicate that the algorithm improves the study precision and achieves reasonably good results in text classification.
基金funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through the Collaborative Research Center 1394 (SFB 1394, No. 409476157) and Project No. 405621160MP would like to thank Prince Matthews for setting up the hcp grain boundaries, Sarath Menon for providing support for CALPHY34Bengt Hallstedt for providing plots of the Mg/Ca and Al/Ca phase diagrams from his assessments, Chad Sinclair together with SFB 1394 for funding a research stay at UBC Vancouver where part of this work was conducted, as well Mira Todorova and Ali Tehranchi for fruitful discussions and Ralf Drautz for critical reading of the manuscript.
文摘We propose a strategy for generating unbiased and systematically extendable training data for machine learning interatomic potentials(MLIP)for multicomponent alloys,called Automated Small SYmmetric Structure Training or ASSYST.Based on exploring the full space of random crystal structures with space groups,it facilitates the construction of training sets for MLIPs in an automatic way without prior knowledge of the material in question.The advantages of this approach are that only cells consisting of few atoms(≈10)are needed for the DFT training set,and the size and completeness of the data set can be systematically controlled with very few parameters.We validate that potentials fitted this way can accurately describe a wide range of binary and ternary phases,random alloys,as well as point and extended defects,that have not been part of the training set.Finally,we estimate the binary phase diagrams with good experimental agreement.We demonstrate that the overall excellent performance is not a coincidence,but a consequence of the extensive sampling in phase space of ASSYST.Overall,this means that ASSYST will enable the largely autonomous generation of highquality DFT reference data and MLIPs.
文摘Rock-fill dykes are often damaged caused by rapid flow currents in a mountainriver. Based on the relationship between the rock size on cover layer and its incipient velocity,it is found that rock weight is directly proportional to the 6th-9th power of incipient velocity,and 50% increase of the velocity may result in about 40 times increase of the rock weight.Therefore, it is inappropriate to improve the stability of rock-fill dykes by simply increasing therock weight. Some new measures should be used to reach this purpose.
