伽利略望远镜与柱面镜组合式长焦综合测量系统

为了实现定距离、较大视场范围某低速点的快速方位角及高程测量要求,采用点型光源、伽利略望远镜与柱面镜组合式长焦光学系统及双正交线阵CCD,搭建了一种复合柱面镜长焦光学测量系统.该组合式长焦光学系统无一次成像面,系统光学长度短,系统前组为伽利略型望远镜型式,接近无焦.在一定测量范围内,选择合适的前组角放大倍率和前组口径等参量,使得在不同位置的点所成线像均与双线阵CCD正交.有针对性地优化光学系统设计、选择合适的系统评价函数并对系统装调及测量原理进行准确度分析.结果表明,该系统在测量距离为10m,视场范围1.5°×1.5°内时,方位角测量误差在±2.5″以内,且系统长度较短,公差较宽松.该系统解决了光源合作目标尺寸严格受限的问题,探测器尺寸较大且成本较低.     

硫系玻璃在无热化长波红外广角镜头中的应用

设计了一种工作波段为8~12μm、有效焦距为5mm、F数为2、视场角为110°的无热化长波红外广角镜头.根据红外无热化光学设计的基本原理,用了常规红外材料硫化锌、硒化锌和硫系玻璃材料制备的六片镜片,通过合理地分配各个镜片的光焦度以及相互间空气间隔等参量,在全视场角为110°的范围内实现接近衍射极限的成像效果.为了更好地控制系统像差,设计利用了硫系玻璃易于精密模压制备非球面的优点,在两片硫系玻璃镜片上设计了3处非球面.设计结果显示:系统在-40℃~60℃的温度范围内均可实现品质良好的红外成像,光学调制函数全视场内均大于0.4,同时在110°视场角时畸变控制在5%以下;实现了在较大视场角条件下控制红外广角镜头的畸变以及系统无热化等设计要求.该系统体积紧凑、质量较轻,整体设计符合民用红外车载镜头的使用要求.     

静态应力作用下预测光学系统性能的计算方法

本文通过计算预测光学性能的方法表征在光学系统组装和外界环境因素影响下的光学系统灵敏度。该方法即通过调制传递函数来表征静态机械应力对光学物镜性能的影响。采用光学干涉仪对经过加工、组装且存在机械应力的光学物镜进行测试,并比较实验调制传递函数与计算模拟分析的调制传递函数。结果表明,计算结果与实验结果相符,证实了本文方法的有效性。     

Angular vibrations of cryogenically cooled double‐crystal monochromators

The effect of angular vibrations of the crystals in cryogenically cooled monochromators on the beam performance has been studied theoretically and experimentally. A simple relation between amplitude of the vibrations and size of the focused beam is developed. It is shown that the double‐crystal monochromator vibrations affect not only the image size but also the image position along the optical axis. Several methods to measure vibrations with the X‐ray beam are explained and analyzed. The methods have been applied to systematically study angular crystal vibrations at monochromators installed at the PETRA III light source. Characteristic values of the amplitudes of angular vibrations for different monochromators are presented.     

Light induced gradient refractive index materials

Controlled and patterned variation of refractive index (wavefront) across a lens surface was obtained via the use of “phase mask”. Gradient interpenetrating network was selected to screen the acrylate and epoxy monomer to obtain necessary refractive index change over the lens surface. The best photoinitiator system was determined to give a stable and transparent wavefront as a mixture of 2 wt% Irgacure 250 (I 250), 1 wt% Isopropylthoxanthone (ITX) and 0.5 wt Irgacure 184 (I 184). It is found that a dipropylene glycol diacrylate (SR 508) and a triethylene glycol dimethacrylate (TGDM) improved the stability of the transparent wavefront because of higher Tg of the network. Haze problem, a consequence of diffusion of one monomer to other network because of the rate differences, was eliminated with IPN composed of TGDM (an acrylate with slow polymerization rate) and bis (3,4‐epoxy cyclohexylmethyl)adipate (BECMA, an epoxy with fast polymerization rate). A high refractive index additive, bromonaphthalene, resulted the best wavefront with lens power when incorporated into BECMA and TGDM IPN. Copyright © 2015 John Wiley & Sons, Ltd.     

Global Solution Approach for a Nonconvex MINLP Problem in Product Portfolio Optimization

The rigorous and efficient determination of the global solution of a nonconvex MINLP problem arising from product portfolio optimization introduced by Kallrath (2003) is addressed. The objective of the optimization problem is to determine the optimal number and capacity of reactors satisfying the demand and leading to a minimal total cost. Based on the model developed by Kallrath (2003), an improved formulation is proposed, which consists of a concave objective function and linear constraints with binary and continuous variables. A variety of techniques are developed to tighten the model and accelerate the convergence to the optimal solution. A customized branch and bound approach that exploits the special mathematical structure is proposed to solve the model to global optimality. Computational results for two case studies are presented. In both case studies, the global solutions are obtained and proved optimal very efficiently in contrast to available commercial MINLP solvers.     

On the Multilevel Structure of Global Optimization Problems

In this paper we will discuss the multilevel structure of global optimization problems. Such problems can often be seen at different levels, the number of which varies from problem to problem. At each level different objects are observed, but all levels display a similar structure. The number of levels which can be recognized for a given optimization problem represents a more complete measure of the difficulty of the problem with respect to the standard measure given by the total number of local minima. Moreover, the subdivision in levels will also suggest the introduction of appropriate tools, which will be different for each level but, in accordance with the fact that all levels display a similar structure, will all be based on a common concept namely that of local move. Some computational experiments will reveal the effectiveness of such tools.     

On Method for Uncertain Multiple Attribute Decision Making Problems with Uncertain Multiplicative Preference Information on Alternatives

The uncertain multiple attribute decision making (UMADM) problems are investigated, in which the information about attribute weights is known partly and the attribute values take the form of interval numbers, and the decision maker (DM) has uncertain multiplicative preference information on alternatives. We make the decision information uniform by using a transformation formula, and then establish an objective-programming model. The attribute weights can be determined by solving the developed model. The concept of interval positive ideal point of alternatives (IPIPA) is introduced, and an approach based on IPIPA and projection to ranking alternatives is proposed. The method can avoid comparing and ranking interval numbers, and can reflect both the objective information and the DMs subjective preferences.     

A theory of complex open resonators in the form of cavity chain

The previous theory ((2,6)) of microwave open resonators has been improved, which can be applicable not only to simple cavities, but also to complex cavities. The comparison between calculations and experimental results shows tha the diffraction Q value of an open resonator may be obtained more precisely from the modified theory than one from the previous theory. According to the theory suggested here, many complex cavities, e.g. a complex cavity with a fourcavity chain, have been analyzed and calculated. It is seen that a variety of field profile forms can exist in complex cavities by adjustment of their cavity geometry.