Abstract:

Abstract:

Abstract:一、日本的任务Ⅰ 1.关于日本地球观测计划的综述(H. Shimoda,日本航空与航天开发厅) 2.从先进地球观测卫星2号(AOEOS-Ⅱ)任务中获得的科学知识(T.Y.Nakajima,日本东海大学)

Abstract:对新型半导体器件--超晶格微制冷器进行了综述分析,对其理论、实验及与电子器件、光电子器件的集成等方面进行了介绍,并对其应用前景及领域进行了分析.

Abstract:The optical readout color infrared imaging based on a blaze grating operates on the principle of highly efficient color seperation. The heat on an infrared focal plane cause the deflection of the infrared heat sensitive film which has a metal reflection surface and a decalescence surface. The metal reflection surface of the infrared heat sensitive film with a blaze grating structure seperates the white light illuminated on it into the color light. At this time, if a CCD image record unit is placed at a particular diffraction angle, different colors corresponding to different diffraction angles can be recorded and a color infrared image can be formed. It is estimated by experiment that this imaging has a NETD of 39mK.

Abstract:With the improvement of the resolution and grey bit of CCDs, the mass of the measured image data will be increased and the data processing speed should be affected. If a common dimension reduction method is used, some details of the target in an image will be lost easily. In this paper, a new intelligent dimension reduction method based on LVQ nueral network and fuzzy c-means clustering technology is proposed. First, the target and background in the measured image are clustered respectively in different clusters; then, the nueral network is trained to reduce the dimension of the image evenly. The experimental result shows that this method can greatly reduce the quantity of the image data to be processed without any influence on the target information.

Abstract:The principle of the Elman nueral network and the features of small infrared target detection are presented in this paper. The Elman neural network is used to estimate the background in an infrared image and then the background noise is eliminated according to the principle of background elimination. Thus, the potential small infrared target is detected. The Neural Network Toolbox in Matlab7.0 is used to do an experiment on programming. The experimental result shows that this method is effective for the detection of small infrared targets.

Abstract:本文在分析现有解复用器件存在的一些问题的基础上,提出了基于分层阵列透射式体全息光栅的用于2×4信道波分复用系统中的波长解复用器件的设计方法.以LiNbO3晶体作为记录介质,红外宽带光源作为波长待解复用光源,实验实现了基于分层阵列透射式体全息光栅的2×4信道波分解复用.实验结果表明,基于分层阵列体全息光栅的波长解复用器件,可以在不影响信道强度的情况下使信道数成倍增加.

Abstract:Atmospheric turbulence is one of the main factors that degrade the performance of wireless optical communication. It can result in the scintillation effect in the received optical intensity. In this paper, the scintillation effect is considered as the multiple noise, and then the performance of the optical communication system is simulated, analyzed and compared with that of the system using Turbo coding. The simulated results show that Turbo code is an effective coding to control atmospheric turbulence.

Abstract:给出了掺钕磷酸盐激光玻璃的光谱特性、能级结构、速率方程和传输方程.研究了掺钕磷酸盐玻璃光波导激光器的输出特性.在忽略放大的自发辐射和激发态吸收的基础上,简化了四能级模型的速率-传输方程.而后利用重叠积分法和龙格-库塔法对掺钕磷酸盐玻璃光波导激光器进行了数值模拟,得到了激光器的输出功率与掺杂浓度、传输损耗和长度等参量之间的关系曲线.理论分析的结果表明,用重掺杂、损耗系数较小、长度合适的波导并优化激光器的制作,就可以获得较高的输出功率和斜率效率,此时的泵浦阈值也较低.

Abstract:本文基于热断层的思想,提出了用于分析人体内热源信息的一种新的热像图分析方法.通过建立有内热源的热传导微分方程,得出方程的解.再结合实际,应用叠加原理将体表的正常体温和异常热源的温度叠加起来,得出了有内热源的体表温度分布表达式,利用该表达式对红外热像图上可能的病变区域的温度数据进行了分析处理.处理过程中选择了两个参考变量:热源的深度h和热源的发热强度q.深度h对应于肿瘤解剖位置的深度,发热强度q对应于肿瘤的性质:良、恶性的判断.临床病例证明,这两个参数对肿瘤的定性、定位是很有效的.

Abstract:用短波红外至长波红外HgCdTe制作的电子注入雪崩光电二极管所呈现的增益和过量噪声特性表现出一种单个致电离载流子的增益过程.结果形成一种具有"理想"特性的电子雪崩光电二极管,这些理想特性包括几乎无噪声的增益.本文报导在研制长波、中波和短波截止红外Hg1-xCdxTe电子雪崩光电二极管方面所取得的成果.这些器件采用p围绕n、正面照射和n /n-/p的圆柱形几何结构,这样的几何结构便于电子注入增益区.这些器件具有一种均匀的指数式增益电压特征,这与k=αn/αe为零的空穴与电子电离系数比是一致的.在中波红外电子