This work presents the static and dynamic analyses of laminated doubly-curved shells and panels of revolution resting on Winkler-Pasternak elastic foundations using the Generalized Differential Quadrature (GDQ) method...This work presents the static and dynamic analyses of laminated doubly-curved shells and panels of revolution resting on Winkler-Pasternak elastic foundations using the Generalized Differential Quadrature (GDQ) method. The analyses are worked out considering the First-order Shear Deformation Theory (FSDT) for the above mentioned moderately thick structural elements. The effect of the shell curvatures is included from the beginning of the theory formulation in the kinematic model. The solutions are given in terms of generalized displacement components of points lying on the middle surface of the shell. Simple Rational Bézier curves are used to define the meridian curve of the revolution structures. The discretization of the system by means of the GDQ technique leads to a standard linear problem for the static analysis and to a standard linear eigenvalue problem for the dynamic analysis. Comparisons between the present formulation and the Reissner-Mindlin theory are presented. Furthermore, GDQ results are compared with those obtained by using commercial programs. Very good agreement is observed. Finally, new results are presented in order to investtigate the effects of the Winkler modulus, the Pasternak modulus and the inertia of the elastic foundation on the behavior of laminated shells of revolution.展开更多
Syria and Iran have formed a special relation in the past four decades. While researchers of international relations have probed deeply into alliance theory in the past half century, current literature in this field c...Syria and Iran have formed a special relation in the past four decades. While researchers of international relations have probed deeply into alliance theory in the past half century, current literature in this field can hardly explain the informal mechanism for Syria-Iran security cooperation. To unravel the puzzle, this paper attempts to put forward a new hypothesis： quasi-alliance. Based on an empirical study of Syria-Iran special relations in the past four decades, it reveals that quasi-alliance is a unique model for security cooperation in international arena paralleling with formal alliance, and its security arrangement has an unique logic, dynamics, mode of management and attributes. In the new framework of analysis, this paper touches down upon the origins, channels, features and tests of Syria-Iran quasi-alliance by focusing on the diplomatic history of their bilateral relations from 1979 to 2017. The bilateral quasi-alliance practice has undergone three stages of combating Iraqi aggression in 1980s, curbing Israel-Turkey axis in 1990s and balancing U.S.-Israel-Saudi-Turkey coalition in the 21st century, particularly since the outbreak of the Syrian civil war.展开更多
The unceasing revolution of the global economy and culture boosts the revolutionary step of the educational circle.Combining the creed of The Guide of College English Teaching in 2016 with the results of investigation...The unceasing revolution of the global economy and culture boosts the revolutionary step of the educational circle.Combining the creed of The Guide of College English Teaching in 2016 with the results of investigation and survey in colleges, a research group in the Institute of Foreign Languages of Hankou University comes up with a revolutionary trial scheme on College English teaching conducted by discovery learning theory, as well as a research method of action research, which is in hope of mending the problems and shortcomings of current College English teaching.展开更多
文摘This work presents the static and dynamic analyses of laminated doubly-curved shells and panels of revolution resting on Winkler-Pasternak elastic foundations using the Generalized Differential Quadrature (GDQ) method. The analyses are worked out considering the First-order Shear Deformation Theory (FSDT) for the above mentioned moderately thick structural elements. The effect of the shell curvatures is included from the beginning of the theory formulation in the kinematic model. The solutions are given in terms of generalized displacement components of points lying on the middle surface of the shell. Simple Rational Bézier curves are used to define the meridian curve of the revolution structures. The discretization of the system by means of the GDQ technique leads to a standard linear problem for the static analysis and to a standard linear eigenvalue problem for the dynamic analysis. Comparisons between the present formulation and the Reissner-Mindlin theory are presented. Furthermore, GDQ results are compared with those obtained by using commercial programs. Very good agreement is observed. Finally, new results are presented in order to investtigate the effects of the Winkler modulus, the Pasternak modulus and the inertia of the elastic foundation on the behavior of laminated shells of revolution.
文摘Syria and Iran have formed a special relation in the past four decades. While researchers of international relations have probed deeply into alliance theory in the past half century, current literature in this field can hardly explain the informal mechanism for Syria-Iran security cooperation. To unravel the puzzle, this paper attempts to put forward a new hypothesis： quasi-alliance. Based on an empirical study of Syria-Iran special relations in the past four decades, it reveals that quasi-alliance is a unique model for security cooperation in international arena paralleling with formal alliance, and its security arrangement has an unique logic, dynamics, mode of management and attributes. In the new framework of analysis, this paper touches down upon the origins, channels, features and tests of Syria-Iran quasi-alliance by focusing on the diplomatic history of their bilateral relations from 1979 to 2017. The bilateral quasi-alliance practice has undergone three stages of combating Iraqi aggression in 1980s, curbing Israel-Turkey axis in 1990s and balancing U.S.-Israel-Saudi-Turkey coalition in the 21st century, particularly since the outbreak of the Syrian civil war.
文摘The unceasing revolution of the global economy and culture boosts the revolutionary step of the educational circle.Combining the creed of The Guide of College English Teaching in 2016 with the results of investigation and survey in colleges, a research group in the Institute of Foreign Languages of Hankou University comes up with a revolutionary trial scheme on College English teaching conducted by discovery learning theory, as well as a research method of action research, which is in hope of mending the problems and shortcomings of current College English teaching.
