新型激光成像雷达图像匹配处理机的设计与实现

激光成像雷达是一种新型成像雷达,图像匹配处理机的使用是该雷达导航应用的先决务件之一。对激光成像雷达的图像匹配处理机进行分析,再进行设计。采用以高速DSP为主处理器,以大规模FPGA为处理器的图像匹配处理机的硬件方案。该方案计算能力强大且可扩展性强,通信接口多样可靠,算法软件实现可灵活修改。实验结果表明,该系统具有高实时性、高数据吞吐率、高可靠性、结构灵活的特点．为激光成像雷达在图像匹配导航中的应用研究提供了强大的处理平台。     

红外成像引信的计算机仿真

文中提出了红外成像引信的计算机仿真方案：首先是建立飞机垢红外辐射模型,建立不同部位（单层蒙皮、内有热源蒙皮、油箱）的热平衡方程,进而得到相应波长范围内的红外辐射强度;接着提出了弹目交会的数学模型,以获得各种交会状态下的飞机红外图像;然后提取包括边解位置、方位和角度大小的图像特特;最后用神经网络的方法对所得特征集进行模式分类。     

非制冷色散式成像光谱仪辐射传递模型

根据接收信号信噪比,研究了基于非制冷微测辐射热计阵列构造色散式成像光谱仪的可行性.综合考虑目标红外辐射特性、大气传输透过率、仪器接收孔径、色散式光谱仪辐射传递特性、红外阵列探测器参数、数据链传输等环节,建立了完善的色散式长波红外成像光谱仪辐射能量传递模型.选用典型地物红外发射率数据,非制冷微测辐射热计红外焦平面阵列参数,利用低分辨率大气辐射传输计算软件LOWTRAN生成大气红外透过率曲线,依据传递模型,计算了以非制冷微测辐射热计阵列为探测器的色散式长波红外成像光谱仪可达到的光谱分辨率,验证了依据非制冷红外探测器构建小型红外成像光谱遥感器的潜力.     

A digital X-ray imaging system based on silicon strip detectors working in edge-on configuration

We present the energy resolution and imaging performance of a digital X-ray imaging system based on a 512-strip silicon strip detector (SSD) working in the edge-on configuration. The SSDs tested in the system are 300 μm thick with 1 or 2-cm-long strips and 100 μm pitch. To ensure a very small dead area of the SSD working in edge-on configuration, the detector is cut perpendicular to the strips at a distance of only 20 μm from the end of the strips. The 512-strip silicon detector is read out by eight 64-channel integrated circuits called DEDIX [Grybos et al., IEEE Trans. Nucl. Sci. NS-54 (2007) 1207]. The DEDIX IC operates in a single photon counting mode with two independent amplitude discriminators per channel. The readout electronic channel connected to a detector with effective input capacitance of about 2 pF has an average equivalent noise charge (ENC) of about 163 el. rms and is able to count 1 Mcps of average rate of input pulses. The system consisting of 512 channels has an excellent channel-to-channel uniformity—the effective threshold spread calculated to the charge-sensitive amplifier inputs is 12 el. rms (at one sigma level). With this system a few test images of a phantom have been taken in the 10–30 keV energy range.     

数字射线检测技术专题(三)——成像过程基本理论

从一般的成像概念,介绍了成像过程的卷积理论和空间频域分析傅里叶变换方法,给出了调制传递函数概念和瑞利判据,并讨论了射线检测的不清晰度与系统扩散函数关系。     

In-situ monitoring of pharmaceutical and specialty chemicals crystallization processes using endoscopy–stroboscopy and multivariate image analysis

This contribution presents the proof of concept of endoscopy–stroboscopy based in situ low-cost imaging of crystallization processes. This low-cost sensor currently is widely spread in the field of medical diagnosis of human vocal chords and this work presents its application in the context of pharmaceutical and chemical crystallization process monitoring. The model compounds used in this study are the active pharmaceutical ingredient (API) flufenamic acid and citric acid.     

Assessment of a handheld fluorescence imaging device as an aid for detection of food residues on processing surfaces

Contamination of food with pathogenic bacteria can lead to foodborne illnesses. Food processing surfaces can serve as a medium for cross-contamination if sanitization procedures are inadequate. Ensuring that food processing surfaces are correctly cleaned and sanitized is important in the food industry to reduce risks of foodborne illnesses and their related costs. A handheld fluorescence imaging device was assessed for detection of three types of food residues that have been associated with foodborne illness outbreaks, i.e. spinach leaf, milk, and bovine red meat, on two commonly used processing surfaces, i.e. high-density polyethylene and food grade stainless steel. Fluorescence excitation at 405 nm was supplied by 4 × 10 W light emitting diodes. Interchangeable optical filters were selected to optimise the contrast between the food residues and processing surfaces, using hyperspectral fluorescence imaging. The fluorescence imaging plus image analysis differentiated food residues from the processing surfaces more clearly than visual inspection in ambient lighting. This optical sensing device can be used to detect food fouling on food processing surfaces over relatively large areas, and has potential for use in the food industry as an aid for detection of specific food residues.     

Detection and analysis of the microdistribution of uranium in the gills of freshwater Corbicula fluminea by SIMS technique

The microdistribution of uranium in the gills of freshwater bivalve Corbicula fluminea following chronic direct exposure to this radioelement has been investigated using the SIMS technique. Different exposure levels and exposure durations have been studied. The SIMS mass spectra and ²³⁸U⁺ ion images produced with a SIMS CAMECA 4F-E7 show an U accumulation with the lower aqueous U concentration (20 μg/L) and the influence of the exposure levels on the bioaccumulation capacities. Furthermore, the ionic images display a heterogeneous distribution of uranium within the gill structure whatever the exposure conditions are. This study, in keeping with the ENVIRHOM French research program, was led to the conclusion that ion microscopy is an appropriate analytical method for trace elements and can give elemental cartography in a biological tissue section.     

Synthesis, radiolabeling and animal studies of [131I]MPPI: A 5-HT1A imaging agent

The synthesis and biological evaluation of serotonin (5-HT1A) imaging agent [131I]-4-iodo-N-{2-[4-(2-methoxyphenyl)-piperazin-1-yl]-ethyl}-N-pridin-2-yl-benzamide ([131I]MPPI) are reported. The chemical structure of aimed compound and intermediates were confirmed by IR, 1HNMR, and MS. Radiochemical purity was above 99% determined by TLC. Biodistribution of [131I]MPPI in rats displayed high uptake in hippocampus and low uptake in cerebellum. The ratio of the uptake of [131I]MPPI in hippocampus to that in cerebellum was 2.90 at 30 min post injection. The radioactivity in thyroid was 0.069 and 0.128% ID/g organ at 5 min and 120 min,respectively, and it was increased with time, which suggests that in vivo deiodination may be the major route of metabolism. Ex vivo autoradiography of brain section displayed significant decrease of radioactivity in hippocampus when pretreated with 8-OH-DPAT, a selective 5HT1A agonist, compared with control. These findings strongly suggested that 131I-MPPI could be used as an in vivo marker for studies of pharmacology of the 5-HT1A receptor system in animals.     

基于单曝光激光层析图像的粒子速度测量系统

首先对目前的PIV(Particle Imaging Velocimetry)技术进行了总结．针对该系统设备复杂、价格昂贵的现实，提出了一种利用对单次曝光的流场空间域激光层析图像进行两次傅立叶变换后获得的频域图像求得最大互相关系数的二维速度场测量的新思路．实验表明：利用该方案有可能开发出针对小速度测量范围的实用粒子图像测速仪．