回转状态下导管螺旋桨水动力特性的数值模拟

采用滑移网格技术和计算流体力学方法,在导管螺旋桨所在的流域内求解其N-S方程,以此模拟在作回转运动的水下机器人流场作用下导管螺旋桨的推力特性,观察螺旋桨在这一环境下的水动力现象.计算结果表明:当来流从尾部流向机器人时,对于尾导管螺旋桨,有机器人影响时其推力系数比无机器人时要小,对处于机器人舷侧的螺旋桨,有机器人时其推力系数比无机器人时要大;当来流从首部流向机器人时其情形刚好相反;而当机器人轴线与流向大致垂直时,有无机器人对螺旋桨推力系数的影响不大.     

Coordinating pricing and inventory decisions in a bounded production system with uncertain yield

Most inventory researches assume that production level can fluctuate arbitrarily. However, large fluctuation of the production level in many firms may be much costly. This paper addresses the coordinating pricing and inventory control problem in a bounded production system with uncertain yield, in which the production level is constrained between a maximum and minimum level in each period and the price can be adjusted dynamically. We show that the optimal policy is the interval base-stock-list-price policy. Also, we study the impact of the production bounds and uncertainty of the yield on the production system. Numerical experiments are also performed to study the impact of parameters on the system.     

An interval method for studying the relationship between the Australian dollar exchange rate and the gold price

This paper proposes an interval method to explore the relationship between the exchange rate of Australian dollar against US dollar and the gold price,using weekly,monthly and quarterly data.With the interval method,interval sample data are formed to present the volatility of variables. The ILS approach is extended to multi-model estimation and the computational schemes are provided. The empirical evidence suggests that the ILS estimates well characterize how the exchange rate relates to the gold price,both in the long-run and short-run.The comparison between the interval and point methods indicates that the difference between the OLS and the ILS estimates is increasing from weekly data to quarterly data,since the lowest frequency point data lost the most information of volatility.     

新媒体艺术发展的文化思辨

新媒体艺术应用方兴未艾.应该重视对新媒体艺术理论的研究,特别是其学术体系的建立.在进行人文思考时,把它作为艺术展现的一种有效手段,以新媒体艺术的形式表现出来,以适应社会越来越广泛的运用和审美需求.应该改革高校对艺术人才培养的传统模式,跨学科培养新媒体艺术人才,以尽快适应新媒体技术和主流受众群体的发展与变化需求.     

糖蜜酒精废水生物脱色的研究进展

糖蜜酒精废水含有大量难降解有机色素,对环境的污染不容忽视.利用专用微生物(细菌、真菌等)对废水进行生物脱色,有一定的应用前景.本文介绍近年来国内外在糖蜜酒精废水生物脱色的研究现状,重点是新的脱色菌种的发现和脱色机理的阐述,最后对未来糖蜜酒精废水脱色的研究发展做初步预测.     

萍乡傩文化论析

"傩"是中国古老的文化现象,它有着悠久的历史,是中华民族文化不可或缺的一部分,对中华民族的发展具有深厚的影响力。萍乡被誉为"中国傩文化之乡",萍乡傩历史悠久,流传甚广,形态原始,傩文化资源丰富,特色明显,"三宝"俱全,有其独树一帜的风格,是学术界研究古傩的活化石。     

列车动载对采空区稳定性影响

为研究列车动载荷对采空区稳定性的影响.概化运行列车和采空区顶板力学模型,分析采空区顶板在以一定速度运动的常力作用下的运动方程,用移动的恒定载荷模拟理想情况下运行列车对采空区顶板及地表的作用过程,进行动力有限元分析.结果表明:与不受外部载荷影响条件下相比,在列车动载荷作用下,地表最大竖向位移和煤柱所承受的最大压应力都有大幅增加,并随着列车的前行最大值逐渐增大,且相应向前移动,列车运行到采空区中部达到最大,然后随着列车的前行最大值开始逐渐减小.     

Homologous fault monitoring technology of redundant INS in airborne avionics systems

Redundant technology plays an important role in improving the reliability and fault-tolerance of the airborne avionics systems. A Markov state transition model is introduced to the reliability analysis of the redundant inertial navigation system （RINS） in airborne navigation systems. An information processing mechanism based on difference filtering is put forward to strengthen the consistency between the outputs of the equal-precision inertial navigation system （INS）. On this basis, the homologous fault monitoring algorithm is designed to realize the homologous fault monitoring of RINS. The simulation is carried out based on the above algorithms, and the results verify the effectiveness of the proposed fault monitoring algorithm based on difference filtering. Research results have good reference value for the configuration and design of RINS in airborne integrated avionics systems.     

房地产寡头有限理性博弈模型的复杂性分析

根据区域房地产行业的成本结构特点,基于政府地价控制行为建立有限理性房地产寡头动态Coumot模型,并分别用理论和数字模拟的方法对其复杂性加以分析.结果表明,区域房地产寡头完全静态博弈Nash均衡在现实中是通过有限理性、不完全信息动态重复博弈达成的;在房产开发商生产技术和管理水平一定下,政府对地价的控制决定区域房地产寡头动态博弈均衡的性质和路径,从而决定房地产开发市场的类型和均衡稳定性.     

混合实时任务的两级调度策略

面向混合实时任务应用,提出一种两级结构调度策略:对周期性实时任务采用时间触发,非周期性实时任务则采用事件触发.先建立任务模型并定义相关概念,然后给出调度策略的架构,并对调度算法、可调度性、抖动、时标间隔及调度策略优化等进行研究.结合windows CE.NET进行的调度策略实验验证结果表明,该方法能提高混合实时任务的确定性,减小抖动.文中最后讨论了时标间隔对处理器利用率和周期分辨率的影响.