Optimal power flow using an Improved Colliding Bodies Optimization algorithm

This paper proposes Improved Colliding Bodies Optimization (ICBO) algorithm to solve efficiently the optimal power flow (OPF) problem. Several objectives, constraints and formulations at normal and preventive operating conditions are used to model the OPF problem. Applications are carried out on three IEEE standard test systems through 16 case studies to assess the efficiency and the robustness of the developed ICBO algorithm. A proposed performance evaluation procedure is proposed to measure the strength and robustness of the proposed ICBO against numerous optimization algorithms. Moreover, a new comparison approach is developed to compare the ICBO with the standard CBO and other well-known algorithms. The obtained results demonstrate the potential of the developed algorithm to solve efficiently different OPF problems compared to the reported optimization algorithms in the literature.     

回转体头部压力分布规律及其对转捩点的影响

以圆头回转体为研究对象,头部线型采用双参数椭圆曲线,利用面元法求解绕流势流流场,利用F.W.Scholkemeier的积分方法,确定该压力分布下的层流边界层,利用P.S.Granville方法求解边界层转捩点.通过变换头部线型参数,以最小压力系数绝对值的下降方向为搜索方向,研究不同头型压力分布的变化规律及其对转捩点的影响.结果表明:最小压力系数绝对值越小的头型其最小压力点离头部驻点的距离越近;不同头型的转捩点不光与其压力分布有关,而且还与其头部长径比有关.     

A recursive algorithm for generating the equations of motion of spatial mechanical systems with application to the five-point suspension

In this paper, a recursive formulation for generating the equations of motion of spatial mechanical systems is presented. The rigid bodies are replaced by a dynamically equivalent constrained system of particles which avoids introducing any rotational coordinates. For the open-chain system, the equations of motion are generated recursively along the serial chains using the concepts of linear and angular momenta. Closed-chain systems are transformed to open-chain systems by cutting suitable kinematic joints and introducing cut-joint constraints. The formulation is used to carry out the dynamic analysis of multi-link five-point suspension. The results of the simulation demonstrate the generality and simplicity of the proposed dynamic formulation.     

Water Law in Spain After 1985

Abstract

Spain has old and complex legislation with regard to water. The current state of evolution in water law is one of vagueness, with contrasting lines of tension: in some areas, the old focus predominates but there are others in which the so-called new water culture can be detected. There are two legal references to mention and comment on: first, the 1978 Spanish Constitution and second, the European Community regulations.     

国际标准化组织动植物油脂国际标准制定（网络首发、推荐阅读）

Increasing volumes of oils and fats are produced annually with a large section that are traded internationally. The International Organization for Standardization(ISO) body develops international standards covering almost all aspects of technology and manufacturing with 23,882 standards currently published. Standards in the animal and vegetable fats and oils sector is developed by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and oils. Standards are developed through consensus by national members that represent ISO in their country. Each Standard is developed within a determined timeframe and goes through various pre-determined stages such as project proposal, development, national voting and commenting on the draft Standard to final publication. ISO TC34/SC11 Standards range from sampling of oils and fats, sample preparation to analysis of its composition, the minor components, and quality and identity parameters as well as contaminants. The analysis results are used by industry for product development, labelling, research and to provide peace of mind for consumers on its safety. An important future trend is the focus on the safety concerns from either environmental contamination(e.g. mineral oils) or processing contaminants such as esters of 3-MCPDs(3-monochloropropane-1,2-diol or 3-chloropropane-1,2-diol).     

Mean velocity field around prismatic bodies in tandem arrangement

This experimental investigation reports the wind tunnel measurements of the mean velocity fields around (a) an isolated square prismatic body with height to width ratio (h/b) of 3 and (b) the same body in tandem with an identical interfering body. In the case of the studies involving interference, the ratios of the centre to centre distance to the body width (G/b) are 4 and 8. The mean velocity components are measured using a Conrad six-hole probe. The approach flow is atmospheric boundary layer with the velocity profile satisfying th power law. It is observed that the effect of interference is considerably large when G/b is small. Due to interference (i) the re-attachment distance shortens and (ii) the maximum values of transverse and vertical velocities are small. The data should be useful for validating computational codes.     

Singular Surfaces in the Theory of Thermoelasticity with Microtemperatures

This work concerns the behavior of shock waves and higher-order discontinuities which propagate in a thermoelastic body with inner structure and microtemperatures. The response of the material is assumed to be linear. The propagation conditions and growth equations that govern the propagation of singular surfaces of order r ≥ 1 are derived. The coupling between the discontinuities in the mechanical and thermal fields is discussed.     

试论我国市场经济体制下的区域协调发展

作者着重分析在我国市场经济体制下区域发展过程中出现的两种问题（即盲目建设、重复建设和急需建设而没有建设）及其成因,并提出增强区域规划科学性和区域协作实效性的两点设想,从而有效遏制重复建设、促成有利整体发展的建设项目,以利于区域协调发展。     

陶瓷骨灰匣试验总结

主要叙述了骨灰匣的釉料所用原料性质及其配方组成，并对骨灰匣的制作工艺，需要改进的几点作了分析     

STATE-SPACE FORMULATION TO GENERALIZED THERMOVISCOELASTICITY WITH THERMAL RELAXATION

The model of the equation of generalized thermoviscoelasticity with one relaxation time is established. The state-space formulation for these equations is introduced. The formulation is valid for problems with or without heat sources. The resulting formulation together with the Laplace transform technique is applied to a variety of problems. The solutions to a thermal shock problem and to a problem of layer media, both without heat sources, are obtained. Also, the effects of a plane distribution of heat sources on the whole and semi-space are studied. A numerical method is employed for the inversion of the Laplace transforms. Numerical results are given and illustrated graphically for each problem. Comparisons are made with the results predicted by the coupled theory.