Schematising hospitality: Ai WeiWei’s activist artwork as a form of dark travel

The article provides a holistic appraisal of activist-artist Ai WeiWei’s work. It argues that, despite its topical innovations and evolution, it continues to be informed by narratives of ‘hospitality’ as an experiential form of engagement with variations of otherness (father, migrant, tourist and refugee). Dividing Ai’s artwork into two overlapping phases of development (national and international/global), it considers the artist’s construction of a cosmopolitan identity with uses of ‘technology’ as embodied and communal property. As Ai’s work on the refugee crisis on Lesbos attests, his (dark) artistic cosmopolitan symbolisations use geo-political imaginaries of justice and hospitality in subsequent projects.     

Complexity: Some Remarks about a Classical Aesthetic Concept

The connection between autonomous art and complexity has been extensively and deeply studied in literary theories in the 20th century. The rise of aesthetic autonomy implies the complexity of literary work as the concept of a sealed container arises from the relationship between the parts that make it up. In this model, the interpretation subject works to directly face literary texts. Instead of pursuing the author’s intention, it aims to reproduce the richness and subtlety of the aesthetic state, and consider the richness and subtlety revealed in the maximum amount of text details in literary works, even if procedurally deviating from the way of mainstream understanding. There is increasing skepticism about the consequences of the autonomous aesthetics, which has been coerced by the development of contemporary capitalism, and it is necessary to develop new forms of aesthetics to reflect the changing social situation.     

介观神经动力学的新探索

文章从认识论和方法论角度分析了神经科学的一个新的探索纲领,美国神经科学家Walter J.Freeman教授用非线性随机混沌理论来处理介观脑神经动力学现象的工作,认为Freeman的神经网络的突现模式对于摆脱身心问题二元论和还原论有重要的启发意义     

The Steiner Tree Problem in Kalmanson Matrices and in Circulant Matrices

We investigate the computational complexity of two special cases of the Steiner tree problem where the distance matrix is a Kalmanson matrix or a circulant matrix, respectively. For Kalmanson matrices we develop an efficient polynomial time algorithm that is based on dynamic programming. For circulant matrices we give an -hardness proof and thus establish computational intractability.     

On the Complexity of Constructing Evolutionary Trees

In this paper we study a few important tree optimization problems with applications to computational biology. These problems ask for trees that are consistent with an as large part of the given data as possible. We show that the maximum homeomorphic agreement subtree problem cannot be approximated within a factor of , where N is the input size, for any 0 in polynomial time unless P = NP, even if all the given trees are of height 2. On the other hand, we present an O(N log N)-time heuristic for the restriction of this problem to instances with O(1) trees of height O(1) yielding solutions within a constant factor of the optimum. We prove that the maximum inferred consensus tree problem is NP-complete, and provide a simple, fast heuristic for it yielding solutions within one third of the optimum. We also present a more specialized polynomial-time heuristic for the maximum inferred local consensus tree problem.     

Defining Problems Fast and Slow: The U‐shaped Effect of Problem Definition Time on Project Duration

This study examines how time spent in problem definition affects problem solving in projects such as Six Sigma projects. Our hypotheses are tested using data collected from 1558 Six Sigma projects in a company. The results show evidence of a U‐shaped relationship between the amount of time spent in the Define phase and project duration. This finding suggests that spending too little time on problem definition potentially causes poor problem formulation, which leads to deficient problem solving and lengthens overall project time. On the other hand, too much time spent on problem definition can lead to unneeded delays in project completion due to diminishing returns on problem definition efforts. Furthermore, the optimal balance between spending too little and too much time depends on prior project experience and project complexity. Prior project experience reduced project completion time and weakened the U‐shaped effect. Conversely, complex projects took longer and appeared to show some evidence of a stronger U‐shaped effect; this suggests balancing the time spent in the Define phase was more challenging for complex projects. Our study also underscores the importance of managing project duration, as projects that were completed faster tended to be associated with higher project savings.     

Hard‐to‐Solve Bimatrix Games

The Lemke–Howson algorithm is the classical method for finding one Nash equilibrium of a bimatrix game. This paper presents a class of square bimatrix games for which this algorithm takes, even in the best case, an exponential number of steps in the dimension d of the game. Using polytope theory, the games are constructed using pairs of dual cyclic polytopes with 2d suitably labeled facets in d‐space. The construction is extended to nonsquare games where, in addition to exponentially long Lemke–Howson computations, finding an equilibrium by support enumeration takes on average exponential time.     

产品扩散策略对企业绩效的影响

从市场需求理论和消费者行为理论出发,引入产品复杂度的调节作用,以中国汽车企业作为研究样本,选取32家中国车企2008～2012年的面板数据,对多次级市场和同一市场两种不同的产品扩散策略与企业绩效关系及产品复杂度在策略-企业绩效关系中的调节作用进行分析.实证结果表明,两种产品扩散策略与绩效之间由负向关系转为正向关系,即两种产品扩散策略与企业绩效呈U型关系;产品复杂度加强了多次级市场产品扩散策略与绩效之间的关系,而弱化了同一市场产品扩散策略与绩效的关系.企业应根据自身的情况,选择合适的扩散方式,合理灵活地利用产品复杂度的调节作用,对企业绩效会起到事半功倍的效果.