解释学循环与美诺悖论—来自海德格尔思想的启示

美诺悖论构成了解释学与知识论的一个重要联结点,长期以来人们对美诺悖论的探讨大都集中于认识论或知识论,然而站在今天欧陆哲学、尤其是海德格尔的立场,解释学与知识论具有某种内在的关联,但它们不是并列的关系,而是源生与衍生的关系。如此看来,解释学同样要面对美诺悖论。解释学理论的核心之一是解释学循环,而解释学循环发展到海德格尔阶段产生了重要的转折,进入到存在论−生存论的层次,它可为理解乃至化解美诺悖论提供一个很好的、富于启发性的视角。     

Reference Frames and Rigid Motions in Relativity: Applications

The concept of rigid reference frame and of constricted spatial metric, given in the previous work [Class. Quantum Grav. 21, 3067 (2004)] are here applied to some specific space-times: in particular, the rigid rotating disc with constant angular velocity in Minkowski space-time is analyzed, a new approach to the Ehrenfest paradox is given as well as a new explanation of the Sagnac effect. Finally the anisotropy of the speed of light and its measurable consequences in a reference frame co-moving with the Earth are discussed.     

The Lattice Solid Model to Simulate the Physics of Rocks and Earthquakes: Incorporation of Friction

The particle-based lattice solid model developed to study the physics of rocks and the nonlinear dynamics of earthquakes is refined by incorporating intrinsic friction between particles. The model provides a means for studying the causes of seismic wave attenuation, as well as frictional heat generation, fault zone evolution, and localisation phenomena. A modified velocity–Verlat scheme that allows friction to be precisely modelled is developed. This is a difficult computational problem given that a discontinuity must be accurately simulated by the numerical approach (i.e., the transition from static to dynamical frictional behaviour). This is achieved using a half time step integration scheme. At each half time step, a nonlinear system is solved to compute the static frictional forces and states of touching particle-pairs. Improved efficiency is achieved by adaptively adjusting the time step increment, depending on the particle velocities in the system. The total energy is calculated and verified to remain constant to a high precision during simulations. Numerical experiments show that the model can be applied to the study of earthquake dynamics, the stick–slip instability, heat generation, and fault zone evolution. Such experiments may lead to a conclusive resolution of the heat flow paradox and improved understanding of earthquake precursory phenomena and dynamics.     

达朗贝尔与斯托克斯佯谬的对比式教学探索

达朗贝尔佯谬和斯托克斯佯谬是流体力学经典内容之一;也是实际教学中较易混淆的知识点. 本文以无界均匀流场中圆球绕流为例;以对比的方式给出有势流动和低雷诺数流动的核心假设、方程的导出、流场速度和压强分布的解析解等;并以云图量化两种流动的区别;厘清问题的假设如何导致了达朗贝尔佯谬和斯托克斯佯谬的产生. 将生动的佯谬与繁多的公式推导紧密结合;有助于学生激发追本溯源的好奇心、进而深化对理论及其局限性的理解.     

THEORETICAL ANALYSIS AND EXPERIMETNAL VERIFICATION FOR PAINLEV碋 PARADOX

含摩擦的多体系统可能存在Painlevé 疑难奇异性-- 多体系统的后续运动可能存在无解(非协调状态)或者多解(不确定状态). 实际系统总要运动下去, 而对应于非协调奇异性状态的多体系统将经历怎样的运动值得探讨. 从计算、实验和理论证明3 个角度研究Painlevé 疑难问题, 验证和证明了多体系统处于非协调状态时其后续运动的切向冲击特征, 并揭示了切向冲击运动的共同规律.     

零售商主导型供应链渠道管理与悖论机制分析

普遍认为零售企业压榨供应商、但实际上供应商利润率远高于零售商是业界关注的一个热点商业悖论问题。通过构建无退货、一般退货、全额退货、线性回扣等体现零售商不同强势地位的供应链渠道管理模型,研究并比较了退货和回扣等强势契约机制以及销售努力对零售供应链管理绩效的影响。分析表明供应商通过批发价定价可以有效转移强势契约带来的风险和成本支付,零售商不能通过强势契约显著提升零售供应链效益。零售商应该利用渠道优势首先强化对批发价定价权的影响,在此基础上合理采用强势契约机制。本文研究很好地解释了零供双方渠道地位与利润水平矛盾的商业悖论问题。     

受r^n分布载荷的楔：佯谬的解决

对表面受与ｒｎ（ｎ≥０）成正比的分布载荷的楔,当楔顶角２α与ｎ之间满足一定关系时,经典解为无穷大,这是一个佯谬．本文采用复变函数方法,研究了这个佯谬的所有情形,并发现存在二次佯谬,即对某些特定的（ｎ,α）,佯谬解仍为无穷大,对此本文也予以解决     

费曼圆盘佯谬及角动量守恒

简述电磁场中角动量守恒定律和费曼圆盘佯谬;对描述费曼圆盘的模型进行了讨论;最后对静场远区的角动量作了定量计算。