The Group of 20(known as G20)was founded in Germany in 1999with an aim at handling international financial crisis,in particular preventing a regional crisis from spreading and becoming a bigger one.It is unfortunate t...The Group of 20(known as G20)was founded in Germany in 1999with an aim at handling international financial crisis,in particular preventing a regional crisis from spreading and becoming a bigger one.It is unfortunate that this meeting mechanism(forum)designed for tackling future impact has to play its role.The US and Europe both witnessed an unprecedented financial crisis with展开更多
Given certain reactions to the ecological crisis as part of the multiple crisis of capitalism （like the so-called energy transition in Germany）, a new mode of development might emerge which can be called green capit...Given certain reactions to the ecological crisis as part of the multiple crisis of capitalism （like the so-called energy transition in Germany）, a new mode of development might emerge which can be called green capitalism. This would shift the terrain of social critique and emancipatory social struggles. The paper introduces the debate on ＂social-ecological transformation＂ which emerged as a radical part of a more comprehensive debate on ＂great＂ or ＂societal transformation＂ and high- lights its core issues： the issue of a necessary attractive mode of production and living for all, the role of pioneers of change and changing political and economic institutions, the acknowledgment of shifting social practices, the requirement for alternative imaginaries or ＂stories＂ of a good life as part of a contested process which is called ＂futuring.＂ As an example for alternative imaginaries, the current debate on ＂degrowth＂ is outlined and evaluated. The second part of the paper focuses more concretely on issues around the formation and existence of a global green-left. After mentioning a crucial problem for any global alternative--i.e., the structural feature of economic and geopolitical competition which historically divided the global Left and pulled it into compromises at national or regional scales--four requirements or characteristics of a global green-left are highlighted： to weaken and change capitalistically driven competition and competitiveness, to push a social-ecological transformation in democratic ways and not at the back ofordinary people （like conservative and liberal proposals for transformation tend to do）, to link more systematically green issues with labor issues and, finally, to transform the overall dispositive of political action from a ＂distributive＂ to a ＂transformative Left.＂ One dimension of such an enhancement, it is concluded, is a broader understanding of the ＂economy＂ itself by acknowledging the demands and achievements of a ＂care revolution＂ which will be crucial for an alternative mode of production and living.展开更多
In this paper, error modeling and analysis of a typical 3-degree of freedom translational Parallel Kine- matic Machine is presented. This mechanism provides translational motion along the Cartesian X-, Y- and Z- axes....In this paper, error modeling and analysis of a typical 3-degree of freedom translational Parallel Kine- matic Machine is presented. This mechanism provides translational motion along the Cartesian X-, Y- and Z- axes. It consists of three limbs each having an arm and forearm with prismatic-revolute-revolute-revolute joints. The moving or tool platform maintains same orientation in the entire workspace due to its joint arrangement. From inverse kinematics, the joint angles for a given position of tool platform necessary for the error modeling and analysis are obtained. Error modeling is done based on the differentiation of the inverse kinematic equations. Variation of pose errors along X, Y and Z directions for a set of dimensions of the parallel kinematic machine is presented. A non-dimensional performance index, namely, global error transformation index is used to study the influence of dimensions and its corresponding global maximum pose error is reported. An attempt is made to find the optimal dimensions of the Parallel Kinematic Machine using Genetic Algorithms in MATLAB. The methodology presented and the results obtained are useful for predicting the performance capability of the Parallel Kinematic Machine under study.展开更多
文摘The Group of 20(known as G20)was founded in Germany in 1999with an aim at handling international financial crisis,in particular preventing a regional crisis from spreading and becoming a bigger one.It is unfortunate that this meeting mechanism(forum)designed for tackling future impact has to play its role.The US and Europe both witnessed an unprecedented financial crisis with
文摘Given certain reactions to the ecological crisis as part of the multiple crisis of capitalism （like the so-called energy transition in Germany）, a new mode of development might emerge which can be called green capitalism. This would shift the terrain of social critique and emancipatory social struggles. The paper introduces the debate on ＂social-ecological transformation＂ which emerged as a radical part of a more comprehensive debate on ＂great＂ or ＂societal transformation＂ and high- lights its core issues： the issue of a necessary attractive mode of production and living for all, the role of pioneers of change and changing political and economic institutions, the acknowledgment of shifting social practices, the requirement for alternative imaginaries or ＂stories＂ of a good life as part of a contested process which is called ＂futuring.＂ As an example for alternative imaginaries, the current debate on ＂degrowth＂ is outlined and evaluated. The second part of the paper focuses more concretely on issues around the formation and existence of a global green-left. After mentioning a crucial problem for any global alternative--i.e., the structural feature of economic and geopolitical competition which historically divided the global Left and pulled it into compromises at national or regional scales--four requirements or characteristics of a global green-left are highlighted： to weaken and change capitalistically driven competition and competitiveness, to push a social-ecological transformation in democratic ways and not at the back ofordinary people （like conservative and liberal proposals for transformation tend to do）, to link more systematically green issues with labor issues and, finally, to transform the overall dispositive of political action from a ＂distributive＂ to a ＂transformative Left.＂ One dimension of such an enhancement, it is concluded, is a broader understanding of the ＂economy＂ itself by acknowledging the demands and achievements of a ＂care revolution＂ which will be crucial for an alternative mode of production and living.
文摘In this paper, error modeling and analysis of a typical 3-degree of freedom translational Parallel Kine- matic Machine is presented. This mechanism provides translational motion along the Cartesian X-, Y- and Z- axes. It consists of three limbs each having an arm and forearm with prismatic-revolute-revolute-revolute joints. The moving or tool platform maintains same orientation in the entire workspace due to its joint arrangement. From inverse kinematics, the joint angles for a given position of tool platform necessary for the error modeling and analysis are obtained. Error modeling is done based on the differentiation of the inverse kinematic equations. Variation of pose errors along X, Y and Z directions for a set of dimensions of the parallel kinematic machine is presented. A non-dimensional performance index, namely, global error transformation index is used to study the influence of dimensions and its corresponding global maximum pose error is reported. An attempt is made to find the optimal dimensions of the Parallel Kinematic Machine using Genetic Algorithms in MATLAB. The methodology presented and the results obtained are useful for predicting the performance capability of the Parallel Kinematic Machine under study.
