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氟硼铍酸钾晶体深紫外区域倍频的非共线匹配
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作者 宋臻 薛建华 +1 位作者 王爱坤 张鑫 《河北师范大学学报(自然科学版)》 CAS 北大核心 2012年第4期364-368,共5页
根据氟硼铍酸钾(KBe2BO3F2,简称KBBF)晶体最新的色散方程以及非共线匹配的条件,采用FORTAN语言变精度数值计算方法,计算了入射波长为400nm的KBBF晶体的类非共线倍频相位匹配角、有效非线性系数和允许角.计算结果显示:在第1象限内存在... 根据氟硼铍酸钾(KBe2BO3F2,简称KBBF)晶体最新的色散方程以及非共线匹配的条件,采用FORTAN语言变精度数值计算方法,计算了入射波长为400nm的KBBF晶体的类非共线倍频相位匹配角、有效非线性系数和允许角.计算结果显示:在第1象限内存在2个匹配方向,第1个匹配方向对应的基频o光和倍频e光的匹配角范围为51.00°-90.00°,50.83°-66.32°,52.68°-78.16°;第2个匹配方向对应的基频o光和倍频e光匹配角范围分别为51.00°-66.00°,60.41°-89.59°,55.71°-77.79°.第1个匹配方向的相位匹配角范围和相应的有效非线性系数比第2个匹配方向大,第1个匹配方向对应的允许角比第2个匹配方向小.因此非共线相位匹配结构下KBBF晶体的Ⅰ类倍频采用第1个匹配方向. 展开更多
关键词 非线性光学 非共线倍频 变精度计算 KBBF晶体 相位匹配角 有效非线性系数 允许角
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An accurate calculation method of the power harmonic parameters based on the delay time theorem of Fourier transform
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作者 TANG Yi FANG Yong-li +2 位作者 YANG Luo SUN Yu-xin YU Zheng-hua 《Journal of Coal Science & Engineering(China)》 2012年第4期438-442,共5页
A new accurate calculation method of electric power harmonic parameters was presented. Based on the delay time theorem of Fourier transform, the frequency of the electric power was calculated, and then, suing interpol... A new accurate calculation method of electric power harmonic parameters was presented. Based on the delay time theorem of Fourier transform, the frequency of the electric power was calculated, and then, suing interpolation in the frequency domain of the windows, the parameters (amplitude and phase) of each harmonic frequency signals were calculated accurately. In the paper, the effect of the delay time and the windows on the electric power harmonic calculation accuracy was analysed. The digital simulation and the physical measurement tests show that the proposed method is effective and has more advantages than other methods which are based on multipoint interpolation especially in calculation time cost; therefore, it is very suitable to be used in the single chip DSP micro-processor. 展开更多
关键词 FFT harmonic analysis windows interpolation in frequency domain power quality time delay theorem
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A precise and accurate acupoint location obtained on the face using consistency matrix pointwise fusion method 被引量:4
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作者 Yang Xuming Ye Yijun +5 位作者 Xia Yong Wei Xuanzhong Wang Zheyu Ni Hongmei Zhu Ying Xu Lingyu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第1期110-116,共7页
OBJECTIVE: To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located.METHODS: On the face, we used an acupoint location from different acupunct... OBJECTIVE: To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located.METHODS: On the face, we used an acupoint location from different acupuncture experts and obtained the most precise and accurate values of acupoint location based on the consistency information fusion algorithm, through a virtual simulation of the facial orientation coordinate system.RESULTS: Because of inconsistencies in each acupuncture expert's original data, the system error could not be modified using the characteristics ofthe general weight calculation. First, we corrected each expert of acupoint location system error itself,to obtain a rational quantification for each expert of acupuncture and moxibustion acupoint location consistent support degree, to obtain pointwise variable precision fusion results, to put every expert's acupuncture acupoint location fusion error enhanced to pointwise variable precision. Then, we more effectively used the measured characteristics of different acupuncture expert's acupoint location, to improve the measurement information utilization efficiency and acupuncture acupoint location precision and accuracy.CONCLUSION: Based on using the consistency matrix pointwise fusion method on the acupuncture experts' acupoint location values, each expert's acupoint location information could be calculated, and the most precise and accurate values of each expert's acupoint location could be obtained. 展开更多
关键词 Information fusion Face recognition Facial acupoint Acupoint location
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