In the present paper, under investigation is a nonisospectral modified Kadomtsev-Petviashvili equation, which is shown to have two Painleve branches through the Painleve analysis. With symbolic computation, two Lax pa...In the present paper, under investigation is a nonisospectral modified Kadomtsev-Petviashvili equation, which is shown to have two Painleve branches through the Painleve analysis. With symbolic computation, two Lax pairs for such an equation are derived by applying the generalized singular manifold method. Furthermore, based on the two obtained Lax pairs, the binary Darboux transformation is constructed and then the N-th-iterated potential transformation formula in the form of Grammian is also presented.展开更多
The typical features of the coordinate and the curvature as well as the recorded time information were analyzed in the hand-written signatures.In the hand-written signature process 10 biometric features were summarize...The typical features of the coordinate and the curvature as well as the recorded time information were analyzed in the hand-written signatures.In the hand-written signature process 10 biometric features were summarized:the amount of zero speed in direction x and direction y,the amount of zero acceleration in direction x and direction y,the total time of the hand-written signatures,the total distance of the pen traveling in the hand-written process,the frequency for lifting the pen,the time for lifting the pen,the amount of the pressure higher or lower than the threshold values.The formulae of biometric features extraction were summarized.The Gauss function was used to draw the typical information from the above-mentioned biometric features,with which to establish the hidden Markov mode and to train it.The frame of double authentication was proposed by combing the signature with the digital signature.Web service technology was applied in the system to ensure the security of data transmission.The training practice indicates that the hand-written signature verification can satisfy the needs from the office automation systems.展开更多
With the assistance of the symbolic computation system Maple,rich higher order polynomial-type conservation laws and a sixth order t/x-dependent conservation law are constructed for a generalized seventh order nonline...With the assistance of the symbolic computation system Maple,rich higher order polynomial-type conservation laws and a sixth order t/x-dependent conservation law are constructed for a generalized seventh order nonlinear evolution equation by using a direct algebraic method.From the compatibility conditions that guaranteeing the existence of conserved densities,an integrable unnamed seventh order KdV-type equation is found.By introducing some nonlinear transformations,the one-,two-,and three-solition solutions as well as the solitary wave solutions are obtained.展开更多
With the aid of symbolic computation system Mathematica, several explicit solutions for Fisher's equation and CKdV equation are constructed by utilizing an auxiliary equation method, the so called G′/G-expansion met...With the aid of symbolic computation system Mathematica, several explicit solutions for Fisher's equation and CKdV equation are constructed by utilizing an auxiliary equation method, the so called G′/G-expansion method, where the new and more general forms of solutions are also constructed. When the parameters are taken as special values, the previously known solutions are recovered.展开更多
Every day we experience relationships with artefacts, which describe material objects made by humans in order to reach a goal and exploit the human feature to plan ahead. Artefacts bring together cognitive evolution a...Every day we experience relationships with artefacts, which describe material objects made by humans in order to reach a goal and exploit the human feature to plan ahead. Artefacts bring together cognitive evolution and technical enhancement. Although artefacts are conceived as technical, we are now facing a relationship with Information Technology (IT) artefacts. IT artefacts include both hardware and software, as a two-sided entity. The definition of IT artefact corresponds with the Saussurean linguistic sign: a two-sided entity constituted by the signifier (hardware) and the signified (software). I claim that IT artefacts share this ontological trait with the linguistic sign. I will show that IT artefacts are the result of design and planning, while language--which is an institution--is not the fabrication of one human but linked to collective human activity.展开更多
Marx’s profound analysis of such social signs as commodity,money,and capital shows that inversion and negation are universal and rule-governed social signs and that social signs attain historical characteristics in c...Marx’s profound analysis of such social signs as commodity,money,and capital shows that inversion and negation are universal and rule-governed social signs and that social signs attain historical characteristics in certain social formations.The basic contradiction arising from human practice,i.e.,their contradictory movement of objectification and nonobjectification,is determined by the dialectical nature of practice,that is,by the relationship of negativity as a medium,and is the concrete expression of the dialectics of negativity in signs.The critique of social semiotics from the perspective of historical materialism is based on practice and reality,and points to the future;it is revolutionary and constructive.At present,the scientific construction of social semiotics can not only promote the development of semiotics,but can also be an important step in deepening historical materialism.展开更多
基金supported by National Natural Science Foundation of China under Grant Nos.60772023 and 60372095the Key Project of the Ministry of Education under Grant No.106033+3 种基金the Open Fund of the State Key Laboratory of Software Development Environment under Grant No.SKLSDE-07-001Beijing University of Aeronautics and Astronautics,the National Basic Research Program of China (973 Program) under Grant No.2005CB321901by the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20060006024the Ministry of Education
文摘In the present paper, under investigation is a nonisospectral modified Kadomtsev-Petviashvili equation, which is shown to have two Painleve branches through the Painleve analysis. With symbolic computation, two Lax pairs for such an equation are derived by applying the generalized singular manifold method. Furthermore, based on the two obtained Lax pairs, the binary Darboux transformation is constructed and then the N-th-iterated potential transformation formula in the form of Grammian is also presented.
基金Project(03JJY3102) supported by the Natural Science Foundation of Hunan Province, China
文摘The typical features of the coordinate and the curvature as well as the recorded time information were analyzed in the hand-written signatures.In the hand-written signature process 10 biometric features were summarized:the amount of zero speed in direction x and direction y,the amount of zero acceleration in direction x and direction y,the total time of the hand-written signatures,the total distance of the pen traveling in the hand-written process,the frequency for lifting the pen,the time for lifting the pen,the amount of the pressure higher or lower than the threshold values.The formulae of biometric features extraction were summarized.The Gauss function was used to draw the typical information from the above-mentioned biometric features,with which to establish the hidden Markov mode and to train it.The frame of double authentication was proposed by combing the signature with the digital signature.Web service technology was applied in the system to ensure the security of data transmission.The training practice indicates that the hand-written signature verification can satisfy the needs from the office automation systems.
文摘With the assistance of the symbolic computation system Maple,rich higher order polynomial-type conservation laws and a sixth order t/x-dependent conservation law are constructed for a generalized seventh order nonlinear evolution equation by using a direct algebraic method.From the compatibility conditions that guaranteeing the existence of conserved densities,an integrable unnamed seventh order KdV-type equation is found.By introducing some nonlinear transformations,the one-,two-,and three-solition solutions as well as the solitary wave solutions are obtained.
文摘With the aid of symbolic computation system Mathematica, several explicit solutions for Fisher's equation and CKdV equation are constructed by utilizing an auxiliary equation method, the so called G′/G-expansion method, where the new and more general forms of solutions are also constructed. When the parameters are taken as special values, the previously known solutions are recovered.
文摘Every day we experience relationships with artefacts, which describe material objects made by humans in order to reach a goal and exploit the human feature to plan ahead. Artefacts bring together cognitive evolution and technical enhancement. Although artefacts are conceived as technical, we are now facing a relationship with Information Technology (IT) artefacts. IT artefacts include both hardware and software, as a two-sided entity. The definition of IT artefact corresponds with the Saussurean linguistic sign: a two-sided entity constituted by the signifier (hardware) and the signified (software). I claim that IT artefacts share this ontological trait with the linguistic sign. I will show that IT artefacts are the result of design and planning, while language--which is an institution--is not the fabrication of one human but linked to collective human activity.
文摘Marx’s profound analysis of such social signs as commodity,money,and capital shows that inversion and negation are universal and rule-governed social signs and that social signs attain historical characteristics in certain social formations.The basic contradiction arising from human practice,i.e.,their contradictory movement of objectification and nonobjectification,is determined by the dialectical nature of practice,that is,by the relationship of negativity as a medium,and is the concrete expression of the dialectics of negativity in signs.The critique of social semiotics from the perspective of historical materialism is based on practice and reality,and points to the future;it is revolutionary and constructive.At present,the scientific construction of social semiotics can not only promote the development of semiotics,but can also be an important step in deepening historical materialism.