Establishmen and vertification of an improved similitude law for dynamic ice force model test

To study the similitude laws for dynamic ice force model test which is a hot problem in ice mechanics.In this paper,a new modified similitude law for dynamic ice force model test is proposed based on ice-induced virbration theory and two reasonable assumptions.And the new law is vertified with an ice-induced pier virbration example.The numerical calculation results show that,firstly,the error of frequency factor between test value and theory value is small as well as that of displacement and velocity;Secondly,the time scale completely meet the similitude relation,the waveforms anastomotic well,and the phenomenon of offset and omit do not occur;Thirdly,as the damping ratio between prototype and model is nearly equal,the improved similitude law will still be applied.Therefore,the new modified similitude law is feasible to study dynamic ice force model test and can provide reference for the ice mechanics.     

磁弹性理论中的守恒定律和路径无关积分

守恒定律与路径无关积分是传统力学中的重要工具,在位错、断裂力学和其他缺陷理论中具有重要的应用价值。由于力场和磁场的共同作用,以及磁弹性材料本身的耦合性质,所以磁弹性体具有更为广泛的守恒定律和路径无关积分。文中通过定义4种不同的热力学函数,应用电磁场理论中的能量矩概念,建立了磁弹性理论中对偶形式的守恒定律,并由这些对偶形式的守恒定律得到了相应的路径无关积分。文中建立的守恒定律和路径无关积分,对研究磁弹性体中的缺陷理论将起到十分重要的作用。     

利用变频调速器对砂布砂纸生产线进行恒张力控制

本文根据弹性力学中的虎克定律，结合砂布砂纸生产特点，分析计算了生产线中基体、应变、速度、张力、转速等参数之间的关系，建立了砂布砂纸生产线中传动辊转速（频率）运动方程。然后利用此规律通过交流变频调速器对电机转速的控制，实现了砂布砂纸生产线的恒定张力控制。系统控制简捷、稳定，调节方便，节约能耗，重复性好，实用性强。     

单榫头叶片精锻成形规律三维热力耦合有限元模拟研究

单榫头叶片是航空发动机中的一类重要叶片.本文以单榫头叶片精锻过程为研究对象,采用热力耦合方法,利用自行开发的面向叶片精锻过程的三维刚粘塑性热力耦合有限元数值模拟系统3D-CTM,模拟分析了不同工艺参数(变形速度、摩擦因子以及坯料锻造温度)下的单榫头叶片精锻过程,研究了不同工艺参数对叶片精锻成形规律的影响.该研究对制定叶片精锻工艺以及发展叶片精锻技术具有重要的理论意义和实用价值.     

Improving the Control Energy in Model Reference Adaptive Controllers Using Fractional Adaptive Laws

This paper presents the analysis of the control energy consumed in model reference adaptive control (MRAC) schemes using fractional adaptive laws, through simulation studies. The analysis is focused on the energy spent in the control signal represented by means of the integral of the squared control input (ISI). Also, the behavior of the integral of the squared control error (ISE) is included in the analysis. The orders of the adaptive laws were selected by particle swarm optimization (PSO), using an objective function including the ISI and the ISE, with different weighting factors. The results show that, when ISI index is taken into account in the optimization process to determine the orders of adaptive laws, the resulting values are fractional, indicating that control energy of the scheme might be better managed if fractional adaptive laws are used.      

Territorial targeting in EU private law

In a series of rulings given in the last few years, the Court of Justice of the European Union (EU) has made use of the concept of targeting by a trader of a particular territorial market as a device for determining the scope of European legislation on private law. The concept is of particular importance in the context of trading activities conducted by means of the Internet, though its significance is not confined to such activities. In particular, the European Court has used the concept of targeting for the purpose of restricting the substantive ambit of intellectual property rights created or harmonised by EU legislation. On the other hand, it has avoided use of the concept of targeting in the context of EU legislation allocating jurisdiction between the courts of the Member States, even in respect of disputes involving intellectual property, except where a legislative text specifically invokes such a concept. The instant paper endeavours to review the position as currently established by the European case-law, and to predict the likely further developments.     

ADALINE based robust control in robotics: a Riemann-Liouville fractional differintegration based learning scheme

This paper presents an approach to improve the performance of intelligent sliding model control achieved by the use of a fundamental constituent of soft computing, named Adaptive Linear Element (ADALINE). The proposed scheme is based on the fractional calculus. A previously considered tuning scheme is revised according to the rules of fractional order differintegration. After a comparison with the integer order counterpart, it is seen that the control system with the proposed adaptation scheme provides (1) better tracking performance, (2) suppression of undesired drifts in parameter evolution and (3) a very high degree of robustness and insensitivity to disturbances. The claims are justified through some simulations utilizing the dynamic model of a two degrees of freedom (DOF) direct drive robot arm and overall, the contribution of the paper is to introduce the fractional order calculus into a robust and nonlinear control problem with some outperforming features that are absent when the integer order differintegration operators are adopted.     

全民健康和医药卫生教育及法规体系研究

我国医药卫生体制改革取得重大进展,但在全民健康教育、卫生人才培养及卫生法律体系建设等方面仍存在巨大挑战。本文总结国内外已有经验,分析我国全民健康和医药卫生教育及法规体系现状和面临的挑战,提出了完善全民健康和医药卫生教育及法规体系的政策建议:构建全民健康教育体系,加强全民健康教育的强制性;根据社会需求培养适宜卫生人才,加强全科医生培养,提高基层医疗卫生服务水平和可及性;尽快推动医药卫生"母法"的出台,并对现行医药卫生相关的法律、规章和规范性文件进行梳理和修订。     

A kinetic flux-vector splitting method for the shallow water magnetohydrodynamics

A kinetic flux-vector splitting (KFVS) scheme for the shallow water magnetohydrodynamic (SWMHD) equations in one- and two-space dimensions is formulated and applied. These equations model the dynamics of a thin layer of nearly incompressible and electrically conducting fluids for which the evolution is nearly two-dimensional with magnetic equilibrium in the third direction. The proposed numerical scheme is based on the direct splitting of macroscopic flux functions of the SWMHD equations. In two-space dimensions the scheme is derived in a usual dimensionally split manner; that is, the formulae for the fluxes can be used along each coordinate direction. The high-order resolution of the scheme is achieved by using a MUSCL-type initial reconstruction and Runge-Kutta time stepping method. Both one- and two-dimensional test computations are presented. For validation, the results of KFVS scheme are compared with those obtained from the space-time conservation element and solution element (CE/SE) method. The accuracy, efficiency and simplicity of the KFVS scheme demonstrate its potential in modeling SWMHD equations.     

Multirate Explicit Adams Methods for Time Integration of Conservation Laws

This paper constructs multirate linear multistep time discretizations based on Adams-Bashforth methods. These methods are aimed at solving conservation laws and allow different timesteps to be used in different parts of the spatial domain. The proposed family of discretizations is second order accurate in time and has conservation and linear and nonlinear stability properties under local CFL conditions. Multirate timestepping avoids the necessity to take small global timesteps—restricted by the largest value of the Courant number on the grid—and therefore results in more efficient computations. Numerical results obtained for the advection and Burgers’ equations confirm the theoretical findings. This work was supported by the National Science Foundation through award NSF CCF-0515170.