基于遗传算法车辆传动系统优化

本文采用遗传算法,以汽车的动力性和燃油经济性最优为目标,同时考虑一定的约束条件,对汽车的传动系参数进行优化,并通过仿真进行验证。     

建材企业绩效考核优化分析

本文首先探讨了建材企业绩效考核工作中面临的主要问题,从考核定位、指标设置、考核主体和结果应用等角度进行了深入分析,最后提出了建材企业绩效考核优化对策。     

Research on Optimizing the Hidden Layer Structure of ANN-Based Model and Its Application in Predicting End-Quench Curves of Steels

IotroductionArtificialneurainetWork(ANN)isahadofinformatboProcessingsystem.ItconsistsofrnanprocessingwtwhichareWandsbolyconnectedoneanothetarerstudying,AN'NcangetinfbrmatiofromtrainjngdaaandcancoirectiyfulunthenoIiljnarmappinghominPuttooutPu.Furthrmore,theest8blishedmodelofANNcanbeusedtopredicttheinfluenceofinputparamt6rsonoutPutvaines.AN'NtechnulgyhasbeenwidelyusedinmaterialandheatndelltdisciPllnebecauseofthepropertieswttonedabove.VNaIayanatai[llusedaneurainetWorktOestirnatehottorsi…     

Modeling techniques for periodic vehicle routing problems

This paper presents a continuous approximation model for the period vehicle routing problem with service choice (PVRP-SC). The PVRP-SC is a variant of the period vehicle routing problem in which the visit frequency to nodes is a decision of the model. This variation can result in more efficient vehicle tours and/or greater service benefit to customers. We present a continuous approximation model to facilitate strategic and tactical planning of periodic distribution systems and evaluate the value of service choice. Further, results from the continuous model can provide guidelines for constructing solutions to the discrete PVRP-SC.     

Optimization and integration of ground vehicle systems

This article deals with the optimal design of ground vehicles and their subsystems, with particular reference to 'active' safety and comfort. A review of state-of-the-art optimization methods for solving vehicle system design problems, including the integration of electronic controls, is given, thus further encouraging the use of such methods as standard tools for automotive engineers. Particular attention is devoted to the class of methods pertaining to complex system design optimization, as well as approaches for the optimal design of complex systems under uncertainty. Some examples of design optimizations are given in the fields of vehicle system dynamics, powertrain/internal combustion engine design, active safety and ride comfort, vehicle system design and lightweight structures, advanced automotive electronics, and smart vehicles.     

多年冻土区天然地面耦合热管的数值传热分析及优化

为了青藏铁路多年冻土路基耦合热管优化设计的需要,建立多年冻土区天然地面耦合热管的相变传热模型,利用该模型研究不同热管管径、气候条件和冷凝段与蒸发段长度比对热管传冷量的影响。结果表明:大管径的热管对于提高热管的传冷量是有利的;在冷凝段与蒸发段长度比大于0.9的条件下,热管传冷量随长度比增大得并不明显,因此建议优化的冷凝段与蒸发段长度比取为稍大于0.9的值;与年平均气温较高的多年冻土区相比,年平均气温较低的多年冻土区更有利于热管的传冷。对比模型计算值和现场实验值表明,提出的模型与实际拟合良好。     

Preparing highway emissions inventories for urban scale modeling: A case study in Philadelphia

Highway emissions represent a major source of many pollutants. Use of local data to model these emissions can have a large impact on the magnitude and distribution of emissions predicted and can significantly improve the accuracy of local scale air quality modeling assessments. This paper provides a comparison of top–down and bottom–up approaches for developing emission inventories for modeling in one urban area, Philadelphia, in calendar year 1999. A bottom–up approach relies on combining motor vehicle emission factors and vehicle activity data from a travel demand model estimated at the road link level to generate hourly emissions data. This approach can result in better estimates of levels and spatial distribution of on-road motor vehicle emissions than a top–down approach that relies on more aggregated information and default modeling inputs.     

软件过程改进的动态建模仿真

给出了一种软件过程改进的动态集成框架，将传统的评估模型与软件过程的动态仿真模型结合起来，为软件过程改进和决策提供定性和定量的评估，并依照能力成熟度模型获得更高的软件开发过程能力。     

翼剖面优化理论在螺旋桨设计和减荷切削中的应用

用Epller的叶剖面设计方法与螺旋浆升力面理论相结合的方法进行了水翼剖面的优化，并将其应用到螺旋桨减振降噪设计中获得了显著的效果，在螺旋桨减荷切削中用优化水翼剖面获得了出奇制胜的成功。     

Future aspects in marine ecosystem modelling

Existing ecosystem models are briefly presented and summarised. The problem of coupling physical and biological models as well as aspects of prediction and predictability are discussed. The general perception that marine ecosystems are inherently unpredictable due to non-linearity becomes questionable if the response of climate variability in marine ecosystems is analysed. Many authors have shown correlations between climate variability and the variability of abundance or biomass of marine organisms such as phytoplankton, zooplankton, benthos or fish recruitment in different parts of the world ocean. In the northern hemisphere, certain species show a linear response to climate variability mainly during winter and spring. However, the underlying mechanisms are not well understood. Often, a phase lag can be observed between climate variability and the reaction of organisms. The identification of a plausible mediator between climate and biology is difficult, since all possible physicochemical mechanisms having a direct or indirect influence on the variability of abundance or biomass of marine organisms have to be considered as mediator.The understanding of the reason of the phase lag, which possibly implies a “biological memory”, and the identification of all possible mediators are necessary to predict the response of marine organisms to climate variability. The identification of mediators will result in an improvement of coupled models, a deeper understanding of physical–biological interaction and the improvement of predictive capability of marine ecosystem models.