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	A fatigue limit evaluation method based on plastic strain incremental energy dissipation theory 期刊论文 OAI收割 ENGINEERING FRACTURE MECHANICS, 2023, 卷号: 282, 页码: 109173 作者: Zu, Ruili; Zhu, Yingbin; Huang XF(黄先富); Huang, Yao; Zhou, Yizhou \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2023/04/20 Fatigue limit Plastic strain incremental energy dissipation theory Infrared thermal imaging Digital image correlation
	Qualitative analysis of gas detection limit of Fourier infrared spectroscopy br 期刊论文 OAI收割 ACTA PHYSICA SINICA, 2022, 卷号: 71 作者: Wang Yu-Hao; Liu Jian-Guo; Xu Liang; Cheng Xiao-Xiao; Deng Ya-Song \| 收藏 \| 浏览/下载：34/0 \| 提交时间：2022/12/23 Fourier transform infrared spectroscopy spectral simulation detection limit greenhouse gas
	Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文 OAI收割 The Astrophysical Journal, 2020, 卷号: 901, 页码: L7 作者: HXMT \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2022/02/08 Radio transient sources Magnetars Soft gamma-ray repeaters 2008 992 1471 Astrophysics - High Energy Astrophysical Phenomena Astrophysics - Instrumentation and Methods for Astrophysics Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of A_J = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 10¹⁴ Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to R_NIR ? 0.025 (fluence index ?0.35).
	An embedded infrared image enhancement system based on DSP and FPGA (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Manufacturing Engineering and Process, ICMEP 2012, April 21, 2012 - April 22, 2012, Kunming, China 作者: Zhang T. 收藏 \| 浏览/下载：53/0 \| 提交时间：2013/03/25 According to the disadvantage of the large noises of histogram equalization algorithm a new adaptive image enhancement algorithm is presented. First the statistical histogram of the infrared image is done. Then the threshold of plateaus Equalization is calculated and the statistical histogram is modified. Finally the bright values of the pixels of the image are changed. An embedded high speed image enhancement processing system on high performance DSP TMS320DM642 and FPGA was designed. Experimental results with real images shown that the system can improve the contrast of the infrared image limit the noises of the enhancement image and effectively enhance the infrared image the running time of the program is shorter so it can meet the requirements of real-time in the project. (2012) Trans Tech Publications.
	Design of reimaging F/1.0 long-wavelength infrared optical system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：45/0 \| 提交时间：2013/03/25 A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations while low dispersion lenses were used in the reimaging system so the optical system do not need achromatic design for a high image quality. Then to correct high-order aberrations resulting from large relative aperture more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here aspheric is selected for easily manufacture. Finally the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Athermal design of hybrid refractive/harmonic diffractive optical system for far-infrared multi-band (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Liu Y.; Liu Y.; Zhang H.; Zhang H.; Sun Q. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 In order to get enough information about the target avoid big chromatic aberration as a result of wide spectrum and the complexity of optical system and adapt different special environment temperature a hybrid refractive/harmonic diffractive optical system in far-infrared multi-band is described in the paper. This diffractive optical system has been designed an athermalized multi-band imaging system with harmonic diffractive element in 15-50m spectrum based on larger 1dispersion capability and particular thermal dispersive power of harmonic diffractive element. Then at the temperature range from 0C to 40C this design can simultaneously meet with all requirements of the imaging system in five harmonic wave bands including15.8-16.2m 18.5-20m 23-25m 30.5-33.5m and 46-50m. In each harmonic wave band the magnification changes as a function of wavelength which creates image registration error. To compensate this shortcoming a zoom optical system is designed with three lenses by means of optical two- component method. The design results show that the hybrid refractive/harmonic diffractive optical system can realize athermalized and achromatic design and the zoom optical system makes half image height at 3.53mm in every harmonic wave band and still realizes aberration compensation action. In the five harmonic wave bands each optical transfer function approaches the diffraction limit at ambient temperature range of 0C to 40C. Finally the system realizes the requirements of portability mini-type and ease for fabrication. 2009 SPIE.
	The Information acquirement of hyperspectral detection system with harmonic diffractive element in infrared dual band (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang Y.; Gao Y. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 A novel design of combination of hybrid system and zoom system in hyperspectral detection imaging is discribed based on the application of harmonic diffractive element (HDE) compared with conventional system. The principles of HDE and infrared zoom hyspectral detection system are presented and the results of a example design are given. It is show that the resolution of this hybrid system is improved and the light power received by Cassegrain system is enlarged. Wavefront aberrations are less than 1/4 wavelength and Modulation Transfer Function in the dual band on each zoom focus location approaches or attains the diffraction limit on 20 cycles/mm.
	The effective gluon propagator in the global color symmetry model 期刊论文 OAI收割 COMMUNICATIONS IN THEORETICAL PHYSICS, 1999, 卷号: 32, 期号: 3, 页码: 331-334 作者: \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2012/08/29 Non-perturbative Calculation Quantum Chromodynamics Infrared Limit Qcd Lattice Vacuum