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关于萨满教原始形态问题的若干探讨 被引量:4
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作者 胡树 《内蒙古社会科学》 北大核心 2003年第1期10-14,共5页
从宗教组织发展的角度上讲 ,萨满教应该是一种形成最早的宗教组织形式 ,而且是一种形成最早的具有普遍性质的宗教形式。对“天”的原始认识构成了此后萨满教“三界”、“九天”等概念形成的基础 ,并且随着社会从氏族走向部族联盟的进化... 从宗教组织发展的角度上讲 ,萨满教应该是一种形成最早的宗教组织形式 ,而且是一种形成最早的具有普遍性质的宗教形式。对“天”的原始认识构成了此后萨满教“三界”、“九天”等概念形成的基础 ,并且随着社会从氏族走向部族联盟的进化发展 ,必然会导致产生出对“天神”的崇拜。从起源地域上看将萨满教仅限定为北方原始宗教 ,其理由并不十分充足。因为从萨满教的原始特征来看 ,她应该是一种存在于更为广泛区域的 。 展开更多
关键词 萨满教 原始形态 普遍 非传播性
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Contrast enhancement of medical ultrasound imaging with reversal phase-inversion pulse technology 被引量:1
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作者 李琴 谭冠政 A.S.M.Libda 《Journal of Central South University》 SCIE EI CAS 2013年第3期696-701,共6页
A new ultrasound contrast imaging technique was proposed for eliminating the harmonic components from the emission signal transmitted by the broadband ultrasonic system.Reversal phase-inversion pulse was used for the ... A new ultrasound contrast imaging technique was proposed for eliminating the harmonic components from the emission signal transmitted by the broadband ultrasonic system.Reversal phase-inversion pulse was used for the first time to separate the contrast harmonics from the harmonics in the emission signal to improve the detection of contrast micro-bubbles.Based on the nonlinear acoustic theory of finite-amplitude effects and the associated distortion of the propagating wave,the Bessel-Fubini series model was applied to describe the nonlinear propagation effects of the reversal phase-inversion pulse,and the Church's equation for zero-thickness encapsulation model was used to produce the scattering-pulse of the bubble.For harmonic imaging,the experiment was performed using a 64-element linear array,which was simulated by Field II.The results show that the harmonic components from the emission signal can be completely cancelled,and the harmonics generated by the nonlinear propagation of the wave through the tissue,can be reduced by 15-30 dB.Compared with the short pulse,the reversal phase-inversion pulse can improve the contrast and definition of the harmonic image significantly. 展开更多
关键词 reversal pulse phase inversion Church model ultrasound imaging CONTRAST
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