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141.
本文简要介绍LabVIEW开发的射频超导量子干涉器(rf SQUID)自动控制系统的虚拟仪器,系统可对超导量子干涉器的工作点进行调整和显示,实现了LabVIEW软件系统与第三方硬件的结合.本文将对系统工作原理、硬件电路组成和软件的设计做简要介绍.  相似文献   
142.
Xin-Jun Yang  Zhao-Qi Wang  Ru-Lian Fu 《Optik》2005,116(7):351-355
Design of a wide-angle off-axis optical see-through head-mounted display (HMD) becomes a challenge since its weight and size are constrained by human factors. Diffractive optics has the potential to play a key role in several areas of head-mounted display. They can reduce size and weight while providing some unique functions that would be difficult to implement with conventional refractive optics. This paper presents a 67°-diagonal field of view, wide spectral band hybrid diffractive-refractive see-through head-mounted display (HMD) using off-axis optics. It possesses a 10 mm exit pupil and a 22 mm eye relief, and satisfies the requirements of human factors. The whole optical system is suitable for a 20 mm-diagonal color liquid crystal display (LCD) with XGA resolution.  相似文献   
143.
从显示的基本原理出发,对高彩模式下的显示特技和兼容性问题作了讨论,提出了显卡识别、虚拟显卡的实施方法,很好的解决了软件的兼容性问题,同时也大大提高了DOS环境下的图形界面的质量.  相似文献   
144.
刘化斌 《发光学报》1996,17(1):68-73
本文给出了X-Y交叉矩阵荧光字符显示屏的基本结构及工作原理,并对它的特性进行研究.讨论了它的亮度与各电极工作电压之间的关系及调制特性.然后,提出了该种显示屏的驱动方案和周边电路的配置方法.最后介绍用该种显示屏制作的HBM-201高亮度显示组件.它的发光亮度在5000cd/m2以上,加滤色片在阳光下清晰可读.  相似文献   
145.
The role of physical testing in product development is changing due to the requirements for faster new product development, reduced tolerance of failures in the field and the emergence of computer aided engineering (CAE) technologies. To be used most effectively, testing must be seen as an integral part of the process for reducing risks associated with new product introductions. Quality function deployment (QFD) and failure modes and effects analysis (FMEA) can be used to establish effective test and development plans that integrate the use of virtual and physical testing. By effectively integrating virtual and physical test technologies significant improvements in product performance can be achieved within shorter times and with reduced development and manufacturing costs. The approach was illustrated by a process of reducing in-cab noise during the design of a new truck.  相似文献   
146.
峰值能量检测及其在被动声纳显示中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
本文介绍子带峰值能量检测方法及其在被动声纳显示和检测中的应用[2-4],同时提出了波束域宽带峰值能量检测算法。新的波束域算法是在已有波束形成的基础上进行处理,不需对原系统进行较大的修改。通过波束域宽带峰值能量检测处理,可以改善声纳显示效果,更加清晰地显示目标方位。相对于高分辨率波束形成算法,两种峰值能量检测算法的运算量都比较低,具有一定的工程应用前景。通过计算机仿真和实测数据处理,验证了所述两种峰值能量算法在提高显示清晰度,减小测向模糊度方面的优点。  相似文献   
147.
A modified version of the virtual internal bond model (VIB) is presented. This involves the introduction of a R-bond restricting the relative rotation freedom of pairwise mass particle. Such a modification allows the VIB model to consider arbitrary values of the Poisson ratio. A linear elastic cohesive law considering both the R-bond and L-bond are assumed. The constitutive relationship is derived using the Cauchy–Born rules. The derived constitutive associates the bond stiffness with the Young’s modulus and Poisson ratio of materials. This gives the bond stiffness in terms of the Young’s modulus and Poisson ratio of materials.The modified VIB model is then used to analyze the tensile crack behavior. In contrast to the cohesive stress method, the deformation-governed concept will be used. The local materials failure is assumed to coincide with the reduction of the bond density due to the local deformation rather than by the local cohesive stress. A phenomenological relationship between the bond density and the deformation is established. The criterion which is applied to determined crack initiation and propagation is built into the constitutive model. As an example, the method is used to study the crack initiation and propagation behavior under tensile loading.  相似文献   
148.
A highly crosslinked poly(styrene–divinyl benzene–trimethyolpropane trimethacrylate) microsphere containing a polyimide prepolymer (PIP) was prepared by a new emulsification method, Shirasu porous glass (SPG) membrane emulsification, and a subsequent radical suspension polymerization. That is, a mixture of styrene, divinyl benzene, trimethyol propane trimethacrylate (TMPTMA), and PIP containing an initiator was permeated through the uniform pores of the SPG membrane into a continuous phase containing a stabilizer to form uniform droplets. Then, the suspension polymerization was carried out at 65 °C for 24 h. The trifunctional crosslinker TMPTMA was added to enhance the destructive strength of the microsphere, and PIP was incorporated into the microsphere to provide an adhesion force by a known self‐curing reaction at 220 °C. The effects of the feed amounts of TMPTMA and PIP on the monomer conversion, size distribution, and destructive strength of the microsphere were investigated. The monomer conversion increased with an increase in TMPTMA. The particle size distribution became narrower as the TMPTMA feed amount increased, but it became broader with an increase in PIP. The destructive strength increased with increases in TMPTMA and PIP. After a heat treatment at 220 °C, the destructive strength decreased because of the heat degradation of the polymer. The addition of TMPTMA suppressed the heat degradation, and PIP could undergo self‐curing at 220 °C. The obtained highly crosslinked uniform microsphere containing PIP has potential applications in liquid‐crystal displays. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2588–2598, 2003  相似文献   
149.
广角无限视景显示系统后投射屏的设计与研究   总被引:2,自引:0,他引:2  
卢颖  范贤德  王勇亮 《光学技术》2003,29(2):158-160
根据球面反射镜成像理论,利用改变光轴的方法,推导出了广角无限视景显示系统后投射屏面形的计算公式,完成了后投射屏最佳面形的设计。对后投射屏外表面散射层的材料和厚度进行了探讨,给出了最佳的选择方案。首次通过热吹模具成型法研制了高精度的整体投射屏。通过试验验证,该投射屏满足设计要求。使用该投射屏的广角无限显示系统具有图像清晰、视场角大、纵深感强等优点,同时观察者的视点还可在一定的出瞳范围内移动。  相似文献   
150.
张杰  顾畹仪 《光子学报》1997,26(10):915-918
本文提出了一种虚波长路径光网络的启发式路由选择算法,它可以用来解决以最小化网络所需波长数目为目标的资源优化问题.该算法应用了基于最大概率路径的选路优化策略.对一个样例网络的数值分析结果表明该算法是有效的.  相似文献   
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