Evolutionary algorithms for solving unconstrained multilevel lot-sizing problem with series structure

This paper presents a comparative study of evolutionary algorithms which are considered to be effective in solving the multilevel lot-sizing problem in material requirement planning (MRP) systems. Three evolutionary algorithms (simulated annealing (SA), particle swarm optimization (PSO) and genetic algorithm (GA)) are provided. For evaluating the performances of algorithms, the distribution of total cost (objective function) and the average computational time are compared. As a result, both GA and PSO have better cost performances with lower average total costs and smaller standard deviations. When the scale of the multilevel lot-sizing problem becomes larger, PSO is of a shorter computational time.     

Ontology-based approach for legal provision retrieval

In this paper, we present an ontology-based approach for legal provision retrieval. The approach aims at assisting the man who knows little about legal knowledge to inquire appropriate provisions. Legal ontology and legal concept probability model are main functional components in our approach. Legal ontology is extracted from Chinese laws by the natural language processing (NLP) techniques. Legal concept probability model is built from corpus, and the model is used to bridge the gap between legal ontology and natural language inquiries.     

Mining evolving association rules for e-business recommendation

Association analysis is an effective data mining approach capable of unveiling interesting associations within a large dataset. Although widely adopted in e-business areas, it still has many difficulties when applied in practice. For instance, there is a mismatch between the static rules discovered and the drifting nature of the user interests, and it is difficult to detect associations from a huge volume of raw user data. This paper presents an effective approach to mine evolving association rules in order to tackle these problems. It is followed by a recommendation model based on the evolving association rules unveiled. Experimental results on an online toggery show that it can effectively unveil people’s shifting interests and make better recommendations accordingly.     

大学生就业预期结构研究

在回顾文献的基础上,开发了大学生就业预期问卷,并用此问卷调查了6所高校1000名大学生,采用探索性和验证性因素分析探讨大学生的就业预期结构.结果表明:大学生的就业预期由个人发展、声望地位、收入报酬和工作环境4个维度构成.而且大学生就业预期的四维结构模型通过了验证性因子分析的验证.最后,论文对研究的结果和意义进行了探讨.     

浅析地铁市郊线物业开发

通过对上海地铁物业开发进行分析与总结,并研究世界地铁与物业开发相结合的成功经验,提出地铁市郊线物业开发模式和开发原则,为上海新建市郊线和其他城市制定适合自己的开发模式提供参考.     

边坡平台大孔径微型桩孔潜孔锤施工工艺研究

分析了潜孔锤钻进、排渣工艺的能量守恒通式,结合湖北通城至湖南平江高速公路边坡拳300mm大孔径微型抗滑桩施工,介绍了设备选型、施工工艺对地质环境条件的调控方法,提出了潜孔锤成孔的极限成孔结构．设计的潜孔锤施工最佳工况对平台微型抗滑桩机械成孔作业具有指导意义．     

Added resistance acting on hull of a non ballast water ship

In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp0.6, are assumed.     

沥青路面预防性养护后评价体系研究

本文结合公路建设项目后评价体系和预防性养护自身的特点,建立了预防性养护后评价体系,提出了预防性养护过程后评价、社会后评价、环境后评价的主要内容、评价方法及评价指标。本文的研究能更加科学地对整个路网进行预防性养护及维修规划,更加合理地使用资金,有效地实现资金费用管理的优化。     

3003铝合金A-TIG焊表面活性剂实验

对3003铝合金进行交流活性钨极氩弧焊(A-TlG)焊接实验,选用氧化物SiO2,TiO2和卤化物MnCl2,NaCl,CaF2作为活性剂,研究了单一成分表面活性剂对焊接熔深的影响。实验结果表明:涂敷活性剂可以一定程度的增加焊缝熔深;氧化物增加焊缝熔深的作用比卤化物大;TiO2作用最显著,熔深增加约80%,且焊缝无裂纹、气孔、夹渣等缺陷。     

Design of fuzzy controller for direct drive wind turbines

Based on the research results of these years, this paper proposes a design of 3MW direct-driven wind generation inverter, and takes much effort in the control algorithm research and MATLAB simulation. Some wonderful results are obtained. All this may provide the reference for practical application. The fuzzy controllers are designed, based on fuzzy logic control theory, which can perfect control of wind generation system with no mathematic model. Models of permanent magnet synchronous generator (PMSG) and dual pulse width modulation (PWM) converter with their controllers are set by MATLAB/Simulink. In addition, experiments are made on the simulation platform of variable speed constant frequency (VSCF) wind power generation system. The behavior of dual PWM converter is demonstrated by simulations and experiment, and the control strategy is valid and correct.