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141.
142.
In this paper we study the families of ETOL and EOL array languages. Standard forms for ETOL and EOL array systems are defined
and closure properties of the families are studied. Relations of these families with other developmental array languages and
other array languages are studied. 相似文献
143.
Numerical analysis indicates that there exists an unexpected new ordered chaos for the bounded one-dimensional multibarrier
potential. For certain values of the number of barriers, repeated identical forms (periods) of the wavepackets result upon
passing through the multibarrier potential. 相似文献
144.
Wiebke S. Diestelkamp 《Designs, Codes and Cryptography》2004,33(3):187-197
An important question in the construction of orthogonal arrays is what the minimal size of an array is when all other parameters are fixed. In this paper, we will provide a generalization of an inequality developed by Bierbrauer for symmetric orthogonal arrays. We will utilize his algebraic approach to provide an analogous inequality for orthogonal arrays having mixed levels and show that the bound obtained in this fashion is often sharper than Raos bounds. We will also provide a new proof of Raos inequalities for arbitrary orthogonal arrays with mixed levels based on the same method. 相似文献
145.
Haiyan Chen Jizhi Dai Yongzhi Liu 《International Journal of Infrared and Millimeter Waves》2004,25(12):1791-1798
IR integrated photonic amplifiers at 1.55m operation will have good foreground in optical phasedarray radars for splitters and signal processing. The saturation gain characteristics of IR integrated photonic waveguide amplifiers (taken Er3+Yb3+ co-doped phosphate glass waveguide amplifiers as an example) are studied theoretically. For the homemade laser glass materials the calculated saturation intensities are 2.22kw /cm2 for signal and 10.15kw/cm2 for pump. The effects of absorption saturation of signal and pump lights on the gain of amplifiers are discussed. 相似文献
146.
线阵CCD拼接技术的应用 总被引:2,自引:0,他引:2
介绍采用性能先进的线阵CCD器件拼接技术实现光学系统的技术要求,给出了使用结果。 相似文献
147.
Changhong Chen Xinjian Yi Jing Zhang Bifeng Xiong 《International Journal of Infrared and Millimeter Waves》2001,22(1):53-58
Mixed vanadium oxide thin films, as VO2 for the main composition are materials for uncooled microbolometer due to their high temperature coefficient of resistance (TCR) at room temperature. This paper describes the design and fabrication of 8-element linear array IR uncooled microbolometers using the films and micromachining technology. The characteristics of the array is investigated in the spectral region of 8–12 m. The fabricated detectors exhibit responsivity of up to 10 KV/W, typical detectivity of 1.89×108 cmHz1/2/W, and thermal time constant of 11 ms, at 296 K and at a frequency of 30 Hz. Furthermore, The uncorrected response uniformity of the linear array bolometers is less than 20%. 相似文献
148.
149.
在构建的光学读出微梁阵列(焦平面阵列FPA)非制冷红外成像系统中,实现了无硅基底FPA置于空气中对人体的热成像. 通过FPA在不同真空度环境条件下的成像结果进行比较,分析了热导和系统噪声值随气压变化的关系,以及对系统成像性能的影响,并对气体分子热运动自由程大于空气传热层特征尺度时的气体热传导模型进行了修正分析和实验验证. 实验结果表明:FPA置于空气中时,气体分子撞击微梁引起的微梁反光板无序振动产生的光学读出噪声成为系统噪声的主要来源. 当真空度小于1Pa时,总热导和光学读出噪声值的变化都趋于平缓;当真空度小于10-2Pa时,空气热导的影响可忽略,总热导降低到微梁感热像素的辐射极限,光学读出噪声也降低到一极小值. 实验结果与理论分析相符合.
关键词:
非制冷红外成像
光学读出
双材料微梁阵列
热导 相似文献
150.
Q. Md. Alfred T. Chakravarty G. Singh S. K. Sanyal 《International Journal of Infrared and Millimeter Waves》2007,28(10):881-887
In radar, planar phased array antenna plays vital role in electronic scanning in the azimuth and elevation direction to the
horizon. In most operations using planar phased array both the coordinates of azimuth and elevation, are steered electronically.
In this paper a conceptual schematic of a phased array antenna with programmable time delay units has been presented. It is
shown that by suitably exploiting the time delay matrix one can have electronic beam rotation around the target axis as required
in conical scan. Thus both the elevation and azimuth motors in conical scan system are replaced by electronic scanning. Heuristically,
we have selected eight consecutive points for beam rotation in a polygon shape and can also be extended almost circular shape
by increasing number of array elements and phase shifter (delays) in the delay matrix. The array requires dual control of
phase gradient and individual phase values. The whole array is controlled by micro-controller. This presents exciting possibilities
in radar operation. 相似文献