基于悬浮吸收层的热电堆红外探测器结构设计

在这项工作中,设计一种新颖的热电堆红外探测器结构。该检测器利用悬浮吸收层-热电堆双层结构来实现高性能,同时具有相对小的尺寸。该双层结构的实现是通过引入两个分离的牺牲层,分别包括热电堆下方的多晶硅膜和其上方的聚酰亚胺沉积实现。尺寸优化后的仿真结果表明,该红外探测器的探测率、响应率和响应时间分别可以达到2.85e8 cmHz （ 1/2） / W, 1800 V / W和6毫秒。此外,本文提出热电堆红外探测器的制造方法是高度兼容于标准的CMOS工艺,这就使其高产量和低成本的生产成为可能。     

Molecular orientation and relaxation in poly(butylene terephthalate)/polycarbonate blends

Rheo-optical Fourier-transform infrared (FTIR) spectroscopy is based on the simultaneous acquisition of stress-strain data and FTIR spectra on-line to the mechanical treatment of polymers and is frequently applied for the characterization of transient structural changes during deformation and stress-relaxation. In the present communication, this technique has been employed in order to investigate the distribution of molecular orientation and its relaxation in uniaxially drawn solution-cast films of semicrystalline partial miscible blends of poly(butylene terephthalate) (PBT) with polycarbonate (PC) containing 10, 30 and 50 wt% PC. The uniaxial deformation of these blend films having a PBT-crystallinity degree ranging from 31 to 12%, in unstretched blends, leads to a appreciable high segmental orientation for the crystalline PBT due to a structural transformation from lamellae to microfibrils. The formation of this fibrillar structure is attributed to non-reversibility of an extended phase with all-trans conformational sequence of the aliphatic segments of PBT, occurring during elongation. The rate of relaxation of this conformational transition, however, increases with increasing amorphous content in the blends. Also it is observed that even with increasing amorphous content in the PBT/PC blends the crystalline PBT shows significant orientation. In such cases, apart from the few lamellae which transform to microfibrils, it is suggested that a stress induced transformation of PBT chains in amorphous PBT-component to irreversible all-trans extended crystalline form also contributes to PBT crystalline orientation. In contrast with this high crystalline orientation, the amorphous PBT located in the interlamellar regions inside the PBT-spherulites show a lower orientation in blends as compared in pure PBT.On the other hand, an overall segmental orientation of PC chains in blends is of lower order which is attributed mainly to low stretching temperature compared to T_g of pure PC. The results are discussed in terms of the resulting spherulitic morphology and the temporary network formed by the elongated PBT and PC chains inside the interlamellar regions, in blends.     

一种快速、高效的红外摇控软件解码技术

通过分析红外遥控发射器发射码的特征,提出一种快速、高效的红外摇控软件解码技术。这种技术仅对发射码的功能码进行解析、存储、数据处理,降低对单片机存储空间的要求,降低了硬件成本,提高了系统的实时性。经实验测试,该方法能保证红外遥控信号的可靠接收。     

经验模态分解在电力绝缘气体SF6红外光谱去噪中的应用

经验模态分解(EMD)是以信号极值特征尺度为度量的时空滤波器,它充分保留了信号本身的非线性和非平稳特征,在信号去噪中具有较大的优势。本文以电力绝缘气体SF6为研究对象,在介绍E MD分解方法的基础上,首先对含噪的SF6光谱信号做EMD分解,得到各阶本征模态函数(IMF),然后对高频的IMF分量用阈值法进行处理,把经过阈值处理后的高频I MF分量与低频IMF分量叠加重构得到去噪后的信号。分析了在不同噪声水平上与小波阈值去噪方法的处理效果。实验结果表明EMD阈值去噪法有效地去除了噪声,较好地保留了光谱的细节信息,与小波阈值去噪方法相比较具有自适应的优势。     

Cavitation characteristics of pit structure in ultrasonic field

Bubble collecting, bubble holding and micro-bubble ejecting characteristics of pit structure and the influence of cavitation bubble on the development of erosion pit are investigated by means of high-speed photography experiments. Pits tend to collect and hold wandering cavitation bubbles. The air holding phenomenon of pits can be a destination of the incubation period in the process of cavitation erosion. The holding bubble tends to eject micro-bubbles from the top of holding cavitation bubble, making the pit a source of nuclei. With bubbles being held in pits, the diameters of pits increase rapidly. But in the given experiment condition, there is a specific stable value beyond which the diameter of pits will not increase. This characteristic will be helpful in understanding and predicting the cavitation erosion process. Supported by the National Basic Research Program of China (“973” Program) (Grant No. 2007CB714105) and the National Natural Science Foundation of China (Grant No. 50539060)     

红外光通信装置的设计与实现

介绍2013年大学生电子设计竞赛F题红外光通信装置的设计与实现。整个系统采用两个LM567（PLL）音频锁相环集成电路来完成红外光通信,性价比高,结构简单。     

Ion-dipole interactions between adsorbed CO and support cations in Pt/K-LTL

The adsorption of carbon monoxide on a non-acidic Pt/K-LTL catalyst has been studied by diffuse reflectance and transmission IR spectroscopy. The CO spectrum is strongly dependent on the experimental conditions. Adsorption on the small Pt clusters in the presence of water gives linear-CO bands between 2060 and 1990 cm^–1 and a bridging-CO band around 1800 cm^–1. In the absence of water, the linear bands are red shifted to about 1940 and 1720 cm^–1, respectively. The frequency shift is attributed to an ion-dipole interaction between adsorbed CO and support cations. The ion-dipole interaction is screened by the adsorbed water leading to a smaller red shift in the CO stretching frequency.     

256元线阵PtSi SB-IRCCD热成像技术研究

本文简述了256元线阵PtSi肖特基势垒红外电荷耦合器件(以下简称SB-IRCCD)的基本工作原理,介绍了IRCCD热成像总体方案及该线阵图像传感器热成像系统的设计。系统设计采用了微机技术,利用Z80—CPU作为摄像机控制处理核心,配合专门的图像帧存贮器来进行图像处理,补偿器件均匀性,抑制固定图像噪声(FPN)及提高信噪比(S/N),降低最小可分辨温差。摄像机系统采用慢存快读的方式,实现显示标准化,与标准电视制式兼容,便于直接与标准视频记录,处理或分析设备接口。最后介绍模拟红外热成像实验情况。     

红外成像导引头抗干扰性能评价指标体系

目前,各类红外成像制导导弹面临的主要问题是抗干扰能力的强弱,包括自然环境干扰和人工干扰两种;因此红外导引头的抗干扰性能成为各类红外制导导弹的关键性能,极大地影响到导弹的作战性能;为了能够合理的评价红外成像导引头的抗干扰性能,就必须制定合理的红外成像导引头抗干扰性能评价指标;为此,笔者根据红外成像导引头的抗干扰工作过程及其特点,以及传统的评价指标,并借鉴深度学习的评价指标,提出了由截获能力、识别能力、跟踪能力和命中精度能力这四方面组成的抗干扰性能评价指标体系;明确了四项指标下的二级指标内涵和计算方法,根据红外仿真与数据处理结果表明,这4种评价指标均可以有效地体现出导引头抗干扰性能的强弱,而且识别能力和命中精度这两个指标更加突出,故笔者所提出的红外成像导引头抗干扰性能指标体系及其计算方法,均可成为红外成像制导导弹抗干扰性能评估的判断依据.     

空地融合的城市道路基础设施数字化技术研究

城市道路基础设施三维模型的重构,在城市道路BIM应用与数字化领域具有重大意义;针对城市交通基础设施数字化重构的需求,对车载激光扫描与无人机倾斜摄影采集技术进行综合运用,提出一套从信息采集、空地点云配准、点云分割到三维重构的完整技术方法;首先使用车载激光扫描技术和无人机倾斜摄影技术对交通基础设施信息进行采集,并使用运动恢复结构算法(SfM,structure from motion)生成基础设施空地点云;其次使用迭代最近点法(ICP,iterative closest point)对空地点云进行精配准,然后利用基于PointNet网络的方法对融合点云进行语义分割;最后对分割出的交通基础设施对象进行三维重构;提出的空地融合的城市交通基础设施数字化技术能够高效地实现交通基础设施重构,为城市交通基础设施数字化提供基础、为后续交通专业领域的应用研究提供便利.