If a system is not disturbed (or invaded) by some law, there is no doubt that each system will move according to the expected law and keep stable. Although such a fact often appears, some unknown law breaks into the...If a system is not disturbed (or invaded) by some law, there is no doubt that each system will move according to the expected law and keep stable. Although such a fact often appears, some unknown law breaks into the system and leads it into turbulence. Using function one direction S-rough sets, this article gives the concept of the F-generation law in the system, the generation model of the F-generation law and the recognition method of the system law. Function one direction singular rough sets is a new theory and method in recognizing the disturbance law existing in the system and recognizing the system law.展开更多
Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of...Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of Herglotz type. Birkhoff's equations for both the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are obtained. According to the relationship between the isochronal variation and the nonisochronal variation, the conditions of the invariance for the Pfaff-Birkhoff-d'Alembert principle of Herglotz type are given. Then, the conserved quantities for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are deduced. Furthermore, the inverse theorems of the conservation theorems are also established.展开更多
Two approximation laws of sliding mode for discrete-time variable structure control systems are proposed to overcome the limitations of the exponential approximation law and the variable rate approximation law. By app...Two approximation laws of sliding mode for discrete-time variable structure control systems are proposed to overcome the limitations of the exponential approximation law and the variable rate approximation law. By applying the proposed approximation laws of sliding mode to discrete-time variable structure control systems, the stability of origin can be guaranteed, and the chattering along the switching surface caused by discrete-time variable structure control can be restrained effectively. In designing of approximation laws, the problem that the system control input is restricted is also considered, which is very important in practical systems. Finally a simulation example shows the effectiveness of the two approximation laws proposed.展开更多
The problem of the presence of Cantor part in the derivative of a solution to a hyperbolic system of conservation laws is considered. An overview of the techniques involved in the proof is given, and a collection of r...The problem of the presence of Cantor part in the derivative of a solution to a hyperbolic system of conservation laws is considered. An overview of the techniques involved in the proof is given, and a collection of related problems concludes the paper.展开更多
A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory (CW...A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory (CWENO) reconstruction for one-dimensional cases, which is generalized to two-dimensional cases by the dimension-by-dimension approach. The large stability domain Runge-Kutta-type solver ROCK4 is used for time integration. The resulting method requires neither the use of Riemann solvers nor the computation of Jacobians and therefore it enjoys the main advantage of the relaxation schemes. The high accuracy and high-resolution properties of the present method are demonstrated in one- and two-dimensional numerical experiments.展开更多
Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation fact...Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation factors of the 32 typical natural gas accumulation systemsin China and studies on the laws controlling distribution of gas are collected. The research showsthat the petroleum accumulation system is the basic unit controlling petroleum generation, migrationand accumulation. Generating intensity, generating amount, accumulating efficiency and migrationdistance plays an important role in the distribution of natural gas. Through analysis on results ofresources evaluation, discovered reserves and residual reserves, potential areas in middle-scaledpetroliferous basins in China are forecasted in this paper. Ordos, Sichuan, Tarim and Qaidam basinsare found out to be the main basins developing and enriching gas accumulation systems.展开更多
The conservation law of second_order nonholonomic system of non_Chetaev's type was studied by means of the Jourdain's principle. The invariant condition of Jourdain's principle under infinitesi...The conservation law of second_order nonholonomic system of non_Chetaev's type was studied by means of the Jourdain's principle. The invariant condition of Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators. Then the conservation law of the system is obtained under certain conditions. Finally a calculating example is given.展开更多
The conservation law of nonholonomic system of second-order non-Chataev's type in event space is studied The Jourdain's principle in event space is presented. The invariant condition of the Jourdain's prin...The conservation law of nonholonomic system of second-order non-Chataev's type in event space is studied The Jourdain's principle in event space is presented. The invariant condition of the Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators in event space. Then the conservation law of the system in event space is obtained under certain conditions. Finally a calculating example is given.展开更多
The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is ...The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is studied based on the aerodynamic parameters and actual flying trial data of a certain UAV. The simulation result shows that this system can realize the recovery safely, stably and accurately.展开更多
System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design...System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design activity, to reduce engineering efforts, and to mitigate project risks. The proposed way is to improve information flow during design by adding definitions and some protocols or rules for communicating a specification or design description. This work presented an objective definition of system status (way of interaction with the rest of the world) along other concepts. This work focused in definitions as mind entities and their importance to rationalize work and mitigate project risks during design. This article presented some simple examples to illustrate the advantages of each aspect of proposed definition of system status and discussed limits and exceptions for such definition. The key finding was the proposed definition which was the simplest while keeping completeness at a given product breakdown level. Such definition of status enforced formal segregation of needs and solutions, and eased the inclusion of behavior definition in specifications.展开更多
We construct a nonlinear integrable coupling of discrete soliton hierarchy, and establish the infinite conservation laws (CLs) for the nonlinear integrable coupling of the lattice hierarchy. As an explicit applicati...We construct a nonlinear integrable coupling of discrete soliton hierarchy, and establish the infinite conservation laws (CLs) for the nonlinear integrable coupling of the lattice hierarchy. As an explicit application of the method proposed in the paper, the infinite conservation laws of the nonlinear integrable coupling of the Volterra lattice hierarchy are presented.展开更多
By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-t...By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-ternative refrlgerant R134a have been studied respective-ly.On the basis of all the research results of this paper,the measure used to save energy for vapor-compressionrefrigeration system has been put out.展开更多
A new kind of weak Noether symmetry is obtained that arises in the study of Birkhoffian systems. The conserved quantities, which includes Noether conserved quantity, Hojman type conserved quantity and new type conserv...A new kind of weak Noether symmetry is obtained that arises in the study of Birkhoffian systems. The conserved quantities, which includes Noether conserved quantity, Hojman type conserved quantity and new type conserved quantity, are also calculated from this symmetry. Finally, two examples are presented to illustrated the application of these new results.展开更多
Firstly,conception of farmers' equal material assistance rights is introduced from the aspects of equal rights,material assistance rights,and farmers' equal material assistance rights.Value function of farmers...Firstly,conception of farmers' equal material assistance rights is introduced from the aspects of equal rights,material assistance rights,and farmers' equal material assistance rights.Value function of farmers' equal material assistance rights is pointed out,which can eliminate the partial policies with urban priority orientation.It is a necessary condition for maintaining the legal and institutional authority,as well as an inevitable choice to realize the social justice and harmony.Current status of the law absence of farmers' equal material assistance rights in China is introduced,which is reflected in the lack of theoretical research on farmers' equal material assistance rights in the law circle,the lack of procedural legal system of farmers' equal material assistance rights at present,and the lack of actual law effectiveness of farmers' equal material assistance rights at present.System construction is a turning point to change the law absence of farmers' material assistance rights.Government should promote the economic development,provide material bases for the system construction of farmers' material assistance rights,enhance the legal consciousness of farmers,cultivate the ability of farmers to participate in equal material assistance rights,strengthen the procedural legislation and judicial justice,and ensure the farmers' material assistance rights.展开更多
To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance comman...To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance command is solved, which can operatethe attack aircraft to automatically complete the flight mission of the preceding stage ofthe terminal weapon delivery, and thus the automatic attack is extended from the stage ofthe terminal weapon delivery to the preceding stage of the terminal weapon delivery.展开更多
基金This project was supported by the Ministry of Education of China (206089)Shangdong Provincial Natural Science Foundation of China (Y2004A04)Fujian Provincial Natural Science Foundation of China (Z051049).
文摘If a system is not disturbed (or invaded) by some law, there is no doubt that each system will move according to the expected law and keep stable. Although such a fact often appears, some unknown law breaks into the system and leads it into turbulence. Using function one direction S-rough sets, this article gives the concept of the F-generation law in the system, the generation model of the F-generation law and the recognition method of the system law. Function one direction singular rough sets is a new theory and method in recognizing the disturbance law existing in the system and recognizing the system law.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11572212 and 11272227)the Innovation Program for Postgraduate in Higher Education Institutions of Jiangsu Province,China(Grant No.KYZZ16-0479)the Innovation Program for Postgraduate of Suzhou University of Science and Technology,China(Grant No.SKCX16-058)
文摘Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of Herglotz type. Birkhoff's equations for both the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are obtained. According to the relationship between the isochronal variation and the nonisochronal variation, the conditions of the invariance for the Pfaff-Birkhoff-d'Alembert principle of Herglotz type are given. Then, the conserved quantities for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are deduced. Furthermore, the inverse theorems of the conservation theorems are also established.
基金This work was supported by the National Natural Science Foundation of China (No.60274099) and the Foundation of Key Laboratory of Process Industry Automation, Ministry of Education
文摘Two approximation laws of sliding mode for discrete-time variable structure control systems are proposed to overcome the limitations of the exponential approximation law and the variable rate approximation law. By applying the proposed approximation laws of sliding mode to discrete-time variable structure control systems, the stability of origin can be guaranteed, and the chattering along the switching surface caused by discrete-time variable structure control can be restrained effectively. In designing of approximation laws, the problem that the system control input is restricted is also considered, which is very important in practical systems. Finally a simulation example shows the effectiveness of the two approximation laws proposed.
文摘The problem of the presence of Cantor part in the derivative of a solution to a hyperbolic system of conservation laws is considered. An overview of the techniques involved in the proof is given, and a collection of related problems concludes the paper.
基金the National Natural Science Foundation of China (60134010)The English text was polished by Yunming Chen.
文摘A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory (CWENO) reconstruction for one-dimensional cases, which is generalized to two-dimensional cases by the dimension-by-dimension approach. The large stability domain Runge-Kutta-type solver ROCK4 is used for time integration. The resulting method requires neither the use of Riemann solvers nor the computation of Jacobians and therefore it enjoys the main advantage of the relaxation schemes. The high accuracy and high-resolution properties of the present method are demonstrated in one- and two-dimensional numerical experiments.
文摘Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation factors of the 32 typical natural gas accumulation systemsin China and studies on the laws controlling distribution of gas are collected. The research showsthat the petroleum accumulation system is the basic unit controlling petroleum generation, migrationand accumulation. Generating intensity, generating amount, accumulating efficiency and migrationdistance plays an important role in the distribution of natural gas. Through analysis on results ofresources evaluation, discovered reserves and residual reserves, potential areas in middle-scaledpetroliferous basins in China are forecasted in this paper. Ordos, Sichuan, Tarim and Qaidam basinsare found out to be the main basins developing and enriching gas accumulation systems.
文摘The conservation law of second_order nonholonomic system of non_Chetaev's type was studied by means of the Jourdain's principle. The invariant condition of Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators. Then the conservation law of the system is obtained under certain conditions. Finally a calculating example is given.
文摘The conservation law of nonholonomic system of second-order non-Chataev's type in event space is studied The Jourdain's principle in event space is presented. The invariant condition of the Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators in event space. Then the conservation law of the system in event space is obtained under certain conditions. Finally a calculating example is given.
文摘The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is studied based on the aerodynamic parameters and actual flying trial data of a certain UAV. The simulation result shows that this system can realize the recovery safely, stably and accurately.
文摘System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design activity, to reduce engineering efforts, and to mitigate project risks. The proposed way is to improve information flow during design by adding definitions and some protocols or rules for communicating a specification or design description. This work presented an objective definition of system status (way of interaction with the rest of the world) along other concepts. This work focused in definitions as mind entities and their importance to rationalize work and mitigate project risks during design. This article presented some simple examples to illustrate the advantages of each aspect of proposed definition of system status and discussed limits and exceptions for such definition. The key finding was the proposed definition which was the simplest while keeping completeness at a given product breakdown level. Such definition of status enforced formal segregation of needs and solutions, and eased the inclusion of behavior definition in specifications.
基金Project supported by the Postdoctoral Science Foundation of China (Grant No. 2011M500404 )the Program for Liaoning Excellent Talents in University,China (Grant No. LJQ2011119)
文摘We construct a nonlinear integrable coupling of discrete soliton hierarchy, and establish the infinite conservation laws (CLs) for the nonlinear integrable coupling of the lattice hierarchy. As an explicit application of the method proposed in the paper, the infinite conservation laws of the nonlinear integrable coupling of the Volterra lattice hierarchy are presented.
文摘By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-ternative refrlgerant R134a have been studied respective-ly.On the basis of all the research results of this paper,the measure used to save energy for vapor-compressionrefrigeration system has been put out.
基金Supported by the National Natural Science Foundation of China (11026090,10772025,10932002,11102001)
文摘A new kind of weak Noether symmetry is obtained that arises in the study of Birkhoffian systems. The conserved quantities, which includes Noether conserved quantity, Hojman type conserved quantity and new type conserved quantity, are also calculated from this symmetry. Finally, two examples are presented to illustrated the application of these new results.
文摘Firstly,conception of farmers' equal material assistance rights is introduced from the aspects of equal rights,material assistance rights,and farmers' equal material assistance rights.Value function of farmers' equal material assistance rights is pointed out,which can eliminate the partial policies with urban priority orientation.It is a necessary condition for maintaining the legal and institutional authority,as well as an inevitable choice to realize the social justice and harmony.Current status of the law absence of farmers' equal material assistance rights in China is introduced,which is reflected in the lack of theoretical research on farmers' equal material assistance rights in the law circle,the lack of procedural legal system of farmers' equal material assistance rights at present,and the lack of actual law effectiveness of farmers' equal material assistance rights at present.System construction is a turning point to change the law absence of farmers' material assistance rights.Government should promote the economic development,provide material bases for the system construction of farmers' material assistance rights,enhance the legal consciousness of farmers,cultivate the ability of farmers to participate in equal material assistance rights,strengthen the procedural legislation and judicial justice,and ensure the farmers' material assistance rights.
文摘To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance command is solved, which can operatethe attack aircraft to automatically complete the flight mission of the preceding stage ofthe terminal weapon delivery, and thus the automatic attack is extended from the stage ofthe terminal weapon delivery to the preceding stage of the terminal weapon delivery.