基于逆向工程的前照灯光学仿真模拟及优化设计

在现代汽车中,汽车前照灯反射镜以自由曲面的应用为主,其整个设计及开发一直是一个比较复杂的难点.文中利用逆向软件imageware对前照灯反射面进行实物模型的重构,并运用光学照明仿真软件lucidshape验证了近光灯反射面模型的配光合理性,分析误差存在的原因.对反射镜进行优化设计,分析研究影响车灯光源利用率的因素,并对反射镜进行了调整以提高光源利用率.整个流程运用计算机辅助软件完成,方便简单,有助于提高前照灯的设计效率,同时提高夜间行车照明的准确度以及驾驶员的舒适性.     

异型光控无眩目车灯

现有行走机械照明配光系统为防眩目,均采用双配光方式,即近光配光和远光配光。近光配光在车辆前方有其他车辆时,形成不致使双方眩目的近距离照明光束;远光配光在车辆前方无其他道路使用者时,形成远距离照明光束。近、远光配光系统一般均用手动(或脚动)开关控制。这种双配光方式受人为因素影响很大,使用不便;又由于远光配光会产生强烈眩目,仍会造成各种交通事故。本发明目的在于提供一种无眩目配光装置,以彻底解决行走机械照明系统眩目问题。它是根据惠更斯原理,采用异型光控方式达到此目的的。     

汽车前雾灯结构设计及配光性能

采用PSX24W光源模块设计了汽车前雾灯的机械机构,进行了光通量以及配光性能的研究,通过防水、热循环以及振动试验来测试前雾灯的配光特性,仿真及实验验证了该汽车前雾灯满足设计要求。     

发光二极管辐射模型的快速建立与验证

基于Source Property Generator软件,根据配光曲线图快速获得相应的光源数据,提出运用非线性回归分析阻尼最小二乘(L-M)法,由模拟公式得到的光源数据与由配光曲线(或测量)获得的光源数据之间的误差,以寻求模拟公式参数的变化步长;然后,由误差均方根与归一化互相关两个判断标准来重建辐射模型的精确性.结果显示:误差均方根低于1%,归一化互相关接近100%.该方法只需提供光源的配光曲线图即可以获得相应的光强分布函数和辐射模型,如果前面的函数设置没有出现错误,一般只要一次就能通过验证;而且只要改变某些要求参数,即可便捷地设计出一系列同类型透镜的辐射模型函数.     

光电跟踪系统结构动态特性分析及优化

针对光电跟踪系统在振动冲击环境条件下结构发生变形导致跟踪精度下降的问题,应用Ansys软件对其结构动态特性进行分析和优化.建立了结构有限元模型,通过应用激光测振仪测试系统在约束情况下的固有频率和振型,验证了有限元模型的正确性与合理性.对系统在给定振动冲击环境条件下,反射镜与各姿态轴之间最大相对转角和角速度进行了数值模拟.通过对基座与反射镜进行结构优化,使系统在满足轻量化要求条件下,反射镜与各轴的最大相对角速度满足了指标要求,从而保证了系统的跟踪精度.     

线聚焦菲涅耳聚光器次级反射镜的仿真设计

本文利用TracePro光学设计软件构建了一小型线聚焦菲涅耳聚光器仿真试验装置,理论研究与仿真实验相结合,通过计算和设置平面镜的跟踪倾角、太阳入射光线方向矢量、太阳直射辐射等参数,实现线聚焦菲涅耳聚光器光学仿真实验。在单块平面镜尺寸为4×0.2m2的情况下,通过改变次级反射镜的类型、次级反射镜与集热管间的距离△H等结构参数进行模拟,得出优化数据,提出聚光器次级反射镜的设计方案。     

泛光照明效果的计算机模拟

从实际灯具的配光曲线及被照面材料的反射特性入手,运用光度学和色度学的计算方法,详细介绍了泛光照明效果的计算机模拟程序的设计思想和分析方法,按照这一思想设计的软件在泛光照明设计中将十分有用。     

Sobel算子和最小二乘法在汽车前照灯近光检测中的应用

本文通过对当前汽车前照灯近光图像边缘检测方法的分析,对影响前照灯近光图像边缘测量精度的原因进行了研究。为提高汽车前照灯近光图像边缘的测量精度,设计了一种基于Sobel算子和最小二乘法的边缘检测方法,经实验验证测量精度有了较大提高。     

LED汽车灯配光设计研究

从汽车前照近光灯出发,提出了一种LED设计方案。采用侧发光型LED为光源,对近光灯的配光要求中划分基础面,并合理调整各子面的面型数据。通过搭建实验模型验证该汽车车灯集中控制系统的可行性,根据所测得的实验数据与理论计算的数据向对比,得到该系统中所存在的一些亚待解决的问题,为今后在该项系统的研究与设计提供正确的方向。     

大型LED双面广告灯箱矢量设计方法

针对发光二极管(LED)广告灯箱近距离、大面积、非对称照明的特点,提出一种基于配光曲线的LED广告灯箱反射面矢量设计方法.根据目标面照度分布要求,对比添加反射面前的目标面照度变化,得到满足均匀照明的广告灯箱配光曲线.使用剪裁法确定反射面的斜率,建立直射光线和反射光线的有效叠加和补偿,实现均匀照明的要求.运用LightTools软件对设计进行模拟仿真,结果表明:目标照度均匀度达到85%,能量利用率超过80%.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with