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11.
YANG Ling-zhen WANG Yun-cai CHEN Guo-fu WANG Yi-shan ZHAO Wei 《光电子快报》2007,3(6):401-403
An Ytterbium-doped mode-locked fiber laser using the polarization sensitive isolator and polarization controllers (PC) is reported. In the normal dispersion, the fiber laser can oscillate at the multi-pulse states by adjusting the position of the PC. On the condition that the polarization state isn’t changed, the outputs of Ytterbium-doped mode-locked fiber laser change from single pulse to multi-pulse by increasing the pump power. The fiber laser can achieve different multi-pulse output by adjusting the PC1 and PC2 carefully. 相似文献
12.
BP neural network is introduced to the fault location field of DWDM optical network in this paper. The alarm characteristics of the optical network equipments are discussed, and alarm vector and fault vector diagrams are generated by analyzing some typical instances. A 17 × 14 × 18 BP neural network structure is constructed and trained by using MATLAB. By comparing the training performances, the best training algorithm of fault location among the three training algorithms is chosen. Numerical simulation results indicate that the sum squared error (SSE) of fault location is less than 0.01, and the processing time is less than 100 ms. This method not only well deals with the missing alarms or false alarms, but also improves the fault location accuracy and real-time ability. 相似文献
13.
ZHANG Ming-jiang WANG Yun-cai 《光电子快报》2006,2(4):246-248
Recently there is an increasing interest in generatingshort optical pulses with lowti ming jitter and tuneablemulti-wavelength due toitsi mportant applicationin op-tical ti me division multiplexed(OTDM),wavelength di-vision multiplexed(WDM)systems,and opt… 相似文献
14.
Ming-hong XIAO Xiao-guang YU Hui-shan MENG Xian-zhu 《光电子快报》2006,2(6):422-425
The electromagnetic radiation is sti mulated when anelectron beampasses a metallic periodic structure like adiffraction grating at a fixed distance close to the sur-face.This phenomenon is known as the Smith-Purcelleffect .The radiation mechanism was pred… 相似文献
15.
LI Dai-zong YU Zhuo CHEN Bu-wen HUANG Chang-jun LEI Zhen-lin YU Jin-zhong WANG Qi-ming 《半导体光子学与技术》1999,5(3):134-138
Using double crystal X-rays diffraction (DCXRD) and atomic force microscopy (AFM), the results of Ge x Si 1- x grown by UHV/CVD from Si 2H 6 and SiH 4 are analyzed and compared. Adsorbates can migrate to the energy-favoring position due to the slow growth rate from SiH 4. In this case, a Si buffer that isolates the effect of substrate on epilayer could not be grown, which results in a pit penetrating into epilayer and buffer. The FWHM is 0.055° in DCXRD from SiH 4. The presence of diffraction fringes is an indication of an excellent crystalline quality. The roughness of the surface is improved if grown by Si 2H 6; however, the crystal quality of the Ge x Si 1- x material became worse than that from SiH 4 due to much larger growth rate from Si 2H 6. The content of Ge is obtained from DCXRD, which indicates the growth rate from Si 2H 6 is largest, then GeH 4, and that from SiH 4 is least. 相似文献
16.
TN-LCD的视角特性 总被引:1,自引:2,他引:1
研究TN-LCD显示器的视角特性,分析视角问题产生的原因。最后定性地分析TN-LCD视角特性的优化和应用。 相似文献
17.
结合TN配电系统的基本要求,分析了相线、零线、地线接错,零线接触不良等带来的影响,用电设备带来空气开关、漏电保护开关跳闸的线路分析,并据此给出了合理建议。 相似文献
18.
MA Jun-shan GU Wen-hua 《光电子快报》2006,2(3):192-194
Chaotic communicationis of great interest because ofa potential applications in secure communications andspread spectrumcommunications .Asemiconductor lasersubject to optical feedback is known to have complexdynamic behavior ,and it can produce chaotic wa… 相似文献
19.
Li-xun Zhang Yun Liao Zhi-yong Dai Zhong-hua Ou Yong-zhi Liu Zeng-shou Peng 《光电子快报》2006,2(5):345-347
The optical fiber temperature sensoris one of the dis-tributed measurement apparatus applied to the smartstructures of civil and military engineering.In the dis-tributedfiber Ramantemperature sensor ,the anti-Stokesand Stokes scattering radiation is sensi… 相似文献
20.
Yan Li Wen-cai Jing Jin-long Yu Yi-mo Zhang Ge Zhou Jin Zhang Da-gong Ji Hong-xia Zhang Hai Dong 《光电子快报》2006,2(5):364-368
It is known that the tolerable residual chromatic dis-persionfor 40 Gb/s transmission systemis only 60 ps/nmor even less[1],and the online chromatic dispersionvaries due tofactors like network reconfigurations ,tem-perature fluctuation,laser ' s wavelengt… 相似文献