The aim of this work was the behavior analysis when a spell checker was integrated as an extra pre-process during the first stage of the test mining. Different models were analyzed, choosing the most complete one cons...The aim of this work was the behavior analysis when a spell checker was integrated as an extra pre-process during the first stage of the test mining. Different models were analyzed, choosing the most complete one considering the pre-processes as the initial part of the text mining process. Algorithms for the Spanish language were developed and adapted, as well as for the methodology testing through the analysis of 2363 words. A capable notation for removing special and unwanted characters was created. Execution times of each algorithm were analyzed to test the efficiency of the text mining pre-process with and without orthographic revision. The total time was shorter with the spell-checker than without it. The key difference of this work among the existing related studies is the first time that the spell checker is used in the text mining preprocesses.展开更多
During long-term use,the clay checker bricks for regenerators of coke ovens on gas side react with the impurities containing Fe and K20,causing foaming,softening and deformation,which is not only related with the impu...During long-term use,the clay checker bricks for regenerators of coke ovens on gas side react with the impurities containing Fe and K20,causing foaming,softening and deformation,which is not only related with the impurity content and properties of the clay checker bricks,but also related with the type and the composition of the dust in the gas.After long term use,the clay checker bricks of coke ovens on air side have relative lower impurities containing Fe and K20.The inferior clay checker bricks,with high impurity content and high porosity,are easy to pulverize and deteriorate due to the oxidationreduction reaction with the iron oxide and the gas.The gas quality shall be concerned for long service life of the coke oven regenerators.展开更多
As one of the research direction in the field of artificial intelligence, the computer game has a great practical significance. Checkers become a represent of complete knowledge game that because of it has few chess p...As one of the research direction in the field of artificial intelligence, the computer game has a great practical significance. Checkers become a represent of complete knowledge game that because of it has few chess pieces, and moves easily, So it can reflect the thought of the computer game better. First, the recursive algorithm of artificial intelligence can achieve the independent moves and checkmates in draughts game program. Second, the optimization of evaluation function makes the program choose beneficial move ways. Third, the game tree can improve the level of computer in-depth thinking, simplify the search scope, and save computer thinking time by pruning, which improve the level of chess program. In this paper, overall framework of intelligent checkers is built from board representation, game tree, valuation optimization. Based on the accumulation of experience, algorithm upgrade, depth analysis of existing framework,then we give a more optimized system framework and then strengthen the computer game level.展开更多
Password authentication is vulnerable to dictionary attacks.Password strength measurement helps users to choose hard-to-guess passwords and enhance the security of systems based on password authentication.Although the...Password authentication is vulnerable to dictionary attacks.Password strength measurement helps users to choose hard-to-guess passwords and enhance the security of systems based on password authentication.Although there are many password strength metrics and tools,none of them produces an objective measurement with inconsistent policies and different dictionaries.In this work,we analyzed the password policies and checkers of top 100 popular websites that are selected from Alexa rankings.The checkers are inconsistent and thus they may label the same password as different strength labels,because each checker is sensitive to its configuration,e.g.,the algorithm used and the training data.Attackers are empowered to exploit the above vulnerabilities to crack the protected systems more easily.As such,single metrics or local training data are not enough to build a robust and secure password checker.Based on these observations,we proposed Hybritus that integrates different websites'strategies and views into a global and robust model of the attackers with multiple layer perceptron(MLP)neural networks.Our data set is comprised of more than 3.3 million passwords taken from the leaked,transformed and randomly generated dictionaries.The data set were sent to 10 website checkers to get the feedbacks on the strength of passwords labeled as strong,medium and weak.Then we used the features of passwords generated by term frequency-inverse document frequency to train and test Hybritus.The experimental results show that the accuracy of passwords strength checking can be as high as 97.7%and over 94%even if it was trained with only ten thousand passwords.User study shows that Hybritus is usable as well as secure.展开更多
文摘The aim of this work was the behavior analysis when a spell checker was integrated as an extra pre-process during the first stage of the test mining. Different models were analyzed, choosing the most complete one considering the pre-processes as the initial part of the text mining process. Algorithms for the Spanish language were developed and adapted, as well as for the methodology testing through the analysis of 2363 words. A capable notation for removing special and unwanted characters was created. Execution times of each algorithm were analyzed to test the efficiency of the text mining pre-process with and without orthographic revision. The total time was shorter with the spell-checker than without it. The key difference of this work among the existing related studies is the first time that the spell checker is used in the text mining preprocesses.
文摘During long-term use,the clay checker bricks for regenerators of coke ovens on gas side react with the impurities containing Fe and K20,causing foaming,softening and deformation,which is not only related with the impurity content and properties of the clay checker bricks,but also related with the type and the composition of the dust in the gas.After long term use,the clay checker bricks of coke ovens on air side have relative lower impurities containing Fe and K20.The inferior clay checker bricks,with high impurity content and high porosity,are easy to pulverize and deteriorate due to the oxidationreduction reaction with the iron oxide and the gas.The gas quality shall be concerned for long service life of the coke oven regenerators.
文摘As one of the research direction in the field of artificial intelligence, the computer game has a great practical significance. Checkers become a represent of complete knowledge game that because of it has few chess pieces, and moves easily, So it can reflect the thought of the computer game better. First, the recursive algorithm of artificial intelligence can achieve the independent moves and checkmates in draughts game program. Second, the optimization of evaluation function makes the program choose beneficial move ways. Third, the game tree can improve the level of computer in-depth thinking, simplify the search scope, and save computer thinking time by pruning, which improve the level of chess program. In this paper, overall framework of intelligent checkers is built from board representation, game tree, valuation optimization. Based on the accumulation of experience, algorithm upgrade, depth analysis of existing framework,then we give a more optimized system framework and then strengthen the computer game level.
基金supported in part by National Key R&D Program of China(2017YFC0820100.2017YFB0802805)in part by the National Natural Science Foundation of China(Grant No.U1736114).
文摘Password authentication is vulnerable to dictionary attacks.Password strength measurement helps users to choose hard-to-guess passwords and enhance the security of systems based on password authentication.Although there are many password strength metrics and tools,none of them produces an objective measurement with inconsistent policies and different dictionaries.In this work,we analyzed the password policies and checkers of top 100 popular websites that are selected from Alexa rankings.The checkers are inconsistent and thus they may label the same password as different strength labels,because each checker is sensitive to its configuration,e.g.,the algorithm used and the training data.Attackers are empowered to exploit the above vulnerabilities to crack the protected systems more easily.As such,single metrics or local training data are not enough to build a robust and secure password checker.Based on these observations,we proposed Hybritus that integrates different websites'strategies and views into a global and robust model of the attackers with multiple layer perceptron(MLP)neural networks.Our data set is comprised of more than 3.3 million passwords taken from the leaked,transformed and randomly generated dictionaries.The data set were sent to 10 website checkers to get the feedbacks on the strength of passwords labeled as strong,medium and weak.Then we used the features of passwords generated by term frequency-inverse document frequency to train and test Hybritus.The experimental results show that the accuracy of passwords strength checking can be as high as 97.7%and over 94%even if it was trained with only ten thousand passwords.User study shows that Hybritus is usable as well as secure.
