Modelling the first- and third-order properties of conceptual thick lenses by using three air-spaced thin lenses

A virtual thick-lens module comprising three air-spaced thin lenses is proposed, which is able to have the identical first-order quantities and third-order Seidel aberrations for just real thick lenses, or groups or components within any thick lens, hence it is capable of studying the aberration behaviours of conceptual lenses without detailed structures. The three thin-lens powers are first evaluated to match the required first-order quantities. Then the aberrations of each thin lens are solved to satisfy the given total aberrations. When the incident rays are changed, each thin lens will induce new aberrations according to the thin-lens formulae. The new system aberrations of the thick module are obtained by adding individual thin-lens aberrations. The module can be directly applied to finite and infinite conjugates, focal and afocal lenses, as well as telecentric and non-telecentric lenses. Examples are given to simulate two real lenses and to optimise the balanced aberrations of a conceptual zoom lens.     

光谱共焦显微镜中色散物镜材料的优化选择

色散物镜是光谱共焦显微镜的关键组件,其轴向色散线性度和色散范围会影响光谱共焦显微镜的性能。在线性轴向色散的理论基础上,研究了优化选择材料组合的方法,给出了优化模型和求解方法,得到了具有最大色散的材料组合及其光焦度分配,并使用光学设计软件对优化结果进行了模拟。模拟结果表明,使用本文优化方法得到的材料组合,波长与轴向色散成线性关系,而且具有最大的轴向色散。使用得到的最大色散材料组合进行色散物镜设计,得到了较好线性度的色散物镜,并具有较短的有效焦距。本文给出的优化选择材料组合的方法可以为设计光谱共焦显微镜提供指导,有效缩短镜筒长度,提高光谱共焦显微镜的性能。     

应用圆二色光谱研究真空对超氧化物歧化酶二级结构的影响

超氧化物歧化酶经真空处理不同时间,利用圆二色光谱研究不同真空时间对超氧化物歧化酶二级结构的影响.结果表明:在3～15 min范围,不同真空处理时间对超氧化物歧化酶的α-螺旋、β-折叠、β-转角及无规卷曲相对含量的影响程度不同.与对照组相比,处理组的α-螺旋、β-转角和无规卷曲含量降低,降幅范围分别为26.1%～41.3%、52.1%～68.8%和2.1%～3.8%;β-折叠增加,增幅范围分别为6.5%～9.2%,表明真空作用使超氧化物歧化酶的二级结构中α-螺旋、β-转角及无规卷曲向β-折叠转化.     

压力式中空超滤膜组件集成与运行分析

以中空纤维超滤膜为出发点,深入分析超滤膜材料的微观和宏观性能、集成膜组件的影响因素。详细阐述了超滤组件的操作和运行方式,并简单介绍了超滤组件膜污染形成机理及清洗的方法,以翔实的数据全面展示了超滤膜集成组件及其工业化应用情况。     

地震动广义动力放大系数谱及其特性研究

传统地震动力放大系数谱是根据地震动最大加速度和结构最大加速度而确定的,没有充分虑及时域非平稳性.通过比较不同周期结构最大反应出现时刻和地震动峰值出现时刻,验证极大峰值对结构反应同样有重要的作用.提出考虑若干极大峰值作用的等效动力放大系数谱的概念,计算不同场地类型下的统计谱并验证其保守性.鉴于考虑频域非平稳性的动力放大系...     

Measurement of the sensitivity and directivity pattern of hydroacoustic measuring modules in artificial tanks

A method of measuring the sensitivity and directivity pattern of hydroacoustic measuring modules of considerable dimensions in artificial tanks is considered. The method is based on the use of a pseudonoise signal. The results of the mathematical modeling and practical application of the method are presented. __________ Translated from Izmeritel’naya Tekhnika, No. 10, pp. 68–70, October, 2006.     

空分膜组件的使用效果与其联接方式间的关系

从串联与并联的角度，对不同联接方式下的空分膜组件的使用效果进行了比较。在试验数据分析的基础上，发现复合型空分膜组件的使用效果跟其联接方式有关，在产氮纯度较高时，串联的效果明显优于并联的，但对于均质型空分膜则不成立；同时要求在采用串联时，须综合考虑温降和压降的影响。     

A tool for the conceptual design of production and operations systems

This paper proposes a conceptual design tool, based upon inferential design theory. It has been specifically developed for the design of production and operations systems, but its use can be extended to other engineering areas, such as mechanical and structural systems. Inferential design theory and its foundation in the inferential theory of learning are briefly outlined. Both theories are based on the idea of using specialised knowledge operators in learning and design, termed knowledge transmutations and design knowledge transmutations respectively. The 24 transmutations existing in the two theories are outlined, and a further 12 design-specific transmutations are proposed. These have been developed as a result of our research. A conceptual design process is proposed, in which design knowledge transmutations are used. A software tool for design, CREDO, is also described and an example of its use in the generation of design concepts for an after-sales service facility is presented. The conclusions discuss the initial methodological experience of using CREDO to generate design concepts. They are based on the introductory use of CREDO at Technion in Israel for teaching purposes. Directions for further research are also provided.     

Development and validation of kurtosis response spectrum analysis for antivibration packaging design taking into consideration kurtosis

In current antivibration packaging designs, transport vibrations are generally assumed to be Gaussian random vibrations, and the cushioning material is designed so that the acceleration root mean square (RMS) transmitted to a product is low. However, transport vibrations are often non-Gaussian random vibrations, and therefore, it is necessary to carry out antivibration packaging design, taking into consideration the non-Gaussianity characteristics and acceleration RMS of the transport vibrations. In this study, a kurtosis response spectrum was proposed, which is an antivibration packaging design index, taking into account the non-Gaussianity of transport vibrations. A kurtosis response spectrum is a plot of the kurtosis of the acceleration response for a series of single degree of freedom (SDOF) systems to the base acceleration input, assuming that the packaged product is the SDOF system. The kurtosis response spectrum was applied to the actual transportation data, and the results confirmed that the kurtosis of product response acceleration is different, depending on the natural frequency of the packaged product. Experiments were conducted using a dummy packaged product, and the experimental results showed good agreement with those of the kurtosis response spectrum analysis. It can be concluded that the kurtosis response spectrum is useful to clarify the effect of natural frequency on the kurtosis response. By referring to the kurtosis response spectrum, packaging engineers can obtain the necessary information to perform antivibration packaging design, taking into account the non-Gaussianity of transport vibrations.     

运用X射线荧光光谱法对石榴石分类鉴定

本文介绍了运用X射线荧光光谱法对石榴石的化学组成元素进行剖析（定性及半定量分析）,通过化学组分的不同来对石榴石进行分类、鉴定。     

二次生长中间相炭微球的粒度分析和结构研究

为研究添加中间相炭微球(MCMB)生球的煤焦油沥青中炭质中间相的发展情况,实验中以热缩具方法于420 ℃下反应12 h得到二次生长的MCMB.对比发现,MCMB的收率较未添加条件下制得的球体有了大幅度的提高.在光学显微镜下观察二次生长后的中间相沥青,发现MCMB的生长具有双向性,即分别向两个尺寸(大球和小球)发展,且随着MCMB加入量的增加,中间相沥青中大球的比例明显提高.粒度分析和扫描电子显微镜(SEM)对MCMB的形貌表征结果也印证了这一结论.同时,SEM下的微观表征还显示大球和小球具有相同的断面结构特征.     

动态图形的设计与信息传播特性解析

目的探讨动态图形设计的基本概念、设计要点及信息传播特性,以期寻求动态图形设计及其信息传播的多元综合方式。方法依据传播学和心理学的基本原理,结合具有代表性的典型案例,从动态图形的元素构成、运动设计及镜头语言等几个方面,对动态图形的信息传播特性及相关的设计要点进行分析和探究。结论动态图形设计是图形设计和影视动画创作的综合,其创作及信息传播具有图形设计与影视动画设计的双重特征,作为一种独特的信息传播方式,动态图形设计综合了图形设计与影视动态设计的信息传播优势,有效提升了信息传播的效果,增强了受众的信息体验。     

次级通路特性及对有源控制算法的影响

在有源噪声控制研究中,次级通路特性对保持系统稳定及快速实现多通道自适应算法具有关键性的作用。首先研究了次级通路特性与自适应有源控制算法及实现的关系,然后对典型的次级通路特性进行了深入研究,最后以封闭空间声场多通道有源控制为例,对次级通路建模及应用进行了仿真研究。     

锂离子二次电池负极用碳材料及其储锂机理

碳和石墨用作锂离子二次电池的负极,其性能很大程度上取决于碳、石墨负极材料的微结构和结晶度。介绍了负极碳材料及其储锂机理,并对今后的发展进行了展望。     

Probabilistic and testing analysis for the variability of load spectrum damage in a fleet

Scatter of fatigue life of a fleet is mainly caused by the variability in structures and load spectra. To ensure the safety in service, the probabilistic characterization of load spectrum variability should be researched in durability analysis and testing work. This paper investigates the variability of load damage rate of a fleet. Based on the flight historical parameters measured by individual aircraft tracking (IAT) from hundreds of aircrafts for a certain type of fighter in China, SWT formula and linear damage rule are used to evaluate the load damage, and then, one average and four other individual load spectra are selected corresponding to different damage severities. Fatigue tests are conducted with the Aluminum alloy 7B04-T74 specimens under five spectra and the Titanium alloy TA15M specimens under three of them. The engineering crack initiation lives are measured and the mean lives are estimated assuming the fatigue life following a log-normal distribution. An obvious difference of at least 2.4 times in the load damage rates is found in the fleet. The fatigue lives of a fleet of aircrafts are calculated by Neuber’s approach, and the probabilities refer to damage severities of those 5 load spectra in a fleet are evaluated. The statistical analysis of the fatigue lives and the probabilities shows that a lognormal distribution can be used to describe the variability of load damage rate of a fleet. The variation of the load damage rate is in the same order of magnitude with that in structural properties.     

5G异构接入网系统频谱资源的统一化表示及动态分配

针对5G通信网络系统提供以大容量、高速率、低时延为主要特征的服务导致频谱资源紧缺现象日趋严重的问题,进行了5G频谱资源动态分配的研究,给出了5G异构接入网频谱资源特征描述、表达方法和一种基于双层优化的动态频谱分配方案。仿真实验结果表明,给出的动态频谱分配方案在系统吞吐量和分配公平性两个指标上均有较好表现,具有较好应用价值。     

臭氧预氧化对城市二级处理水中残留有机物分子量分布的影响及超滤膜阻力变化分析

利用对城市二级处理水进行了臭氧预氧化,测定了水中残留有机物的分子量分布,并采用PVDF超滤膜对不同分子量分布的二级处理水进行了过滤.结果发现,水中有机物的分子量分布对膜的阻力构成影响很大,堵孔阻力和滤饼阻力对膜污染阻力起控制作用,有机物分子量分布与膜阻力之间有如下关系:1)2/151特别是d/>5/3的有机物则是形成膜表面滤饼的主体.     

最小二乘法拟合压力传感器二次曲线及精度分析

提出了用最小二乘法拟合压力传感器输入输出关系二次曲线的方法.文中对这两种方法作了比较,并用实例说明二次多项式拟合结果可大大提高测量的精度;其次,采用矩阵运算及MATLAB编程可提高计算效率.     

Ti缓冲层对ZnO薄膜吸收特性和荧光光谱的影响

采用射频磁控溅射法在Si衬底和玻璃衬底上制备了ZnO/Ti薄膜,利用紫外-可见分光光度计和荧光分光光度计等技术表征了ZnO/Ti薄膜的光学特性,研究了Ti缓冲层的厚度对ZnO薄膜的影响。透射吸收光谱显示所有ZnO薄膜在可见光区域的平均透过率超过80%,当引入缓冲层后,薄膜的紫外吸收边先向长波方向移动,且随着缓冲层厚度的增加紫外吸收边向短波方向移动。薄膜的荧光光谱显示,所有样品出现了位于390nm的紫外发光峰,435和487nm的蓝光双峰以及525nm的绿光峰,并对各发光峰的来源进行了探讨。     

断层带影响下隧道二衬结构爆破振动特性与安全判据

针对隧道爆破开挖穿越断层破碎带时,围岩松散、破碎,易造成隧道结构失稳的问题。以龙南隧道爆破施工为工程背景,依据现场爆破振动测试结果,建立ANSYS/LS-DYNA动力有限元数值模型,研究了断层带影响下隧道二衬结构爆破振动特性,提出了以应力为控制标准的振速安全判据。结果表明:隧道拱脚处振速衰减最快,破碎带内隧道各部位振速衰减幅度普遍大于相邻围岩段;隧道二衬剪应力峰值位于拱顶处,拉应力峰值位于拱脚处;结合应力与振速关系,建立基于二衬极限强度的爆破振动安全判据,分析得到隧道衬砌在断层带影响下更容易失稳,在龙南隧道爆破条件下衬砌爆破安全振速为10 cm/s,爆破施工单段最大药量为23.89 kg。