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phase-shift presaturation for water peak suppression in biomolecular NMR experiments

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Science China(Life Sciences) 1997年第4期40卷 345-350页

作者：毛希安叶朝辉 State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics Chinese Academy of Sciences Wuhan 430071 China

The phase-shift presaturation technique for water suppression is further improved with effective phase cycling. In the two-dimensional NMR COSY, NOESY and HMQC experiments of biosamples, the water sup-pression factor reaches the order of 10 , making it possible to detect 13C NMR signals in extremely diluted (2 mmol/L) aqueous solutions.

关键词： biomolecular NMR water suppression phase-shift presaturation phase cycling.

Information Encryption Based on Using Arbitrary Two-Step phase-shift Interferometry

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Optics and Photonics Journal 2011年第4期1卷 204-215页

作者： Chi-Ching Chang Wen-Ho Wu Min-Tzung Shiu Wang-Ta Hsieh Je-Chung Wang Hon-Fai Yau 不详

A deterministic phase-encoded encryption system is proposed. A lenticular lens array (LLA) sheet with a particular LPI (lenticular per inch) number is chosen as a modulator (key) instead of the random phase molator. The suggested encryption scheme is based on arbitrary two-step phase-shift interferometry (PSI), using an unknown phase step. The encryption and decryption principle is based on an LLA in arbitrary unknown two-step PSI. Right key holograms can be used to theoretically show that the object wavefront is the only one left in the hologram plane and that all accompanying undesired terms are eliminated. The encrypted image can therefore be numerically and successfully decrypted with the right key in the image plane. The number of degrees of freedom of the encryption scheme increases with the distance from the object and the LLA to the CCD, and also with the unknown phase-step and the LLA LPI number. Computer simulations are performed to verify the encryption and decryption principles without a key, with the wrong key and with the right key. Optical experiments are also performed to validate them.

关键词： Deterministic phase-Encoded Encryption Arbitrary Two-Step phase-shift Interferometry Lenticular Lens Array

Numerical study of hydrodynamic mechanism of dynamic tidal power

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Water Science and Engineering 2018年第3期11卷 220-228页

作者： Peng Dai Ji-sheng Zhang Jin-hai Zheng Kees Hulsbergen Gijs van Banning Jeroen Adema Zi-xuan Tang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Harbor Coastal and Offshore Engineering Hohai UniversityNanjing 210098China Hulsbergen Hydraulic Innovation&Design H2iD Dieren6953 CRThe Netherlands ARCADIS Nederland BV Zwolle8017 JSThe Netherlands

Dynamic tidal power is a new way of capturing tidal energy by building a water head using a dike perpendicular to the coast. This study explored the hydrodynamic mechanism of the water head across an intended dynamic tidal power dike system using the Delft3 D-FLOW software module. The propagating wave was simulated in a rectangular domain with a horizontal sea bottom at a 30-m depth. A significant water head was created across the dike by blocking the water. The water head increased with increasing dike length and increasing undisturbed tidal current acceleration. The maximum water head for the dike with a length of 50 km, located 900 km from the western boundary, was 2.15 m,which exceeded the undisturbed tidal range. The time series of the water head behaved in a manner identical to the undisturbed tidal current acceleration. The distribution of the water head over the dike assumed an elliptical shape. A parasitic wave was generated at the attachment and scattered outward. The phase lag across the dike did not behave as a linear function of the detour distance.

关键词： Dynamic tidal power Marine renewable energy Added mass phase-shift Coastal engineering Delft3D

A new method for PQ disturbance detection and identification

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 392-397页

作者：吕干云程浩忠丁屹峰翟海保 Dept.of Information Science and Engineering Zhejiang Normal University Dept.of Electrical Engineering Shanghai Jiaotong UniversityShanghai 200030China Dept.of Electrical Engineering Shanghai Jiaotong University

A new method based on phase-shift and N-1 Support Vector Machines(SVMs)is presented for power quality(PQ)disturbance detection and *** phase-shift and simple algebra operation,the method detects out the PQ disturbances easily and *** a data dealing process is carried out to extract features from the detecting *** SVM theory is introduced into the identification of PQ disturbances.N kinds of PQ disturbances are classified with an N-1 SVMs *** testing results show that the proposed method can detect and classify the PQ disturbances ***,the classifier has a good performance on training speed and correct ratio.

关键词： PQ disturbances phase-shift SVMs classifier identification

3D surface reconstruction based on binocular vision using structured light

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Journal of Beijing Institute of Technology 2016年第3期25卷 413-417页

作者： MA Zhi-feng HAN Fu-hai WANG Teng-fei School of Information and Electronics Beijing Institute of Technology Beijing 100081 China Troop 63600 People's Liberation Army Jiuquan 732750 Gansu China

A 3D surface reconstruction method using a binocular stereo vision technology and a coded structured light,which combines a gray code with phase-shift has been *** accuracy of the 3 D surface reconstruction mainly depends on the decoding of gray code views and phase-shift *** order to find the boundary accurately,gray code patterns and their inverses are projected onto a human eye plaster *** period dislocation between the gray code views and the phase-shift views in the course of decoding has been analyzed and a new method has been proposed to solve *** splicing method is based on feature *** result of the 3D surface reconstruction shows the accuracy and reliability of our method.

关键词： 3D surface reconstruction structured light gray code phase-shift

一种具有宽输入电压范围的集成Buck-Boost LLC级联变换器

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中国电机工程学报 2016年第6期36卷 1667-1673页

作者：孙孝峰仇江峰栗晓华骆志伟电力电子节能与传动控制河北省重点实验室(燕山大学电气工程学院) 河北省秦皇岛市066004 北京航天发射技术研究所北京市海淀区100076

研究一种集成Buck-Boost LLC（integrated Buck-Boost LLC,IBBLLC）变换器。该变换器适用于宽输入电压范围场合的应用,通过开关管的共用变换器减少了开关管数量。通过采用PWM＋phase-shift控制,使得原边各个开关管在全输入电压和全负载... 详细信息

研究一种集成Buck-Boost LLC（integrated Buck-Boost LLC,IBBLLC）变换器。该变换器适用于宽输入电压范围场合的应用,通过开关管的共用变换器减少了开关管数量。通过采用PWM＋phase-shift控制,使得原边各个开关管在全输入电压和全负载范围内均能够实现零电压开通（zero voltage switching,ZVS）。文中首先介绍变换器的拓扑结构及直流增益。其次详细分析变换器的工作模式及前级电感Lb对变换器性能的影响,为变换器参数的选取提供了理论依据。此外,研究变换器的ZVS特性,给出变换器能够实现ZVS的工作区域。最后搭建一台200～450 V输入、14 V/80 A输出的实验样机,实验结果验证了理论分析的正确性及方案的可行性。

关键词： Buck-Boost LLC phase-shift 宽输入电压范围

EFFECTS OF NUCLEAR-FORCE CHARGE-SYMMETRY BREAKING ON LOW ENERGY NN SCATTERING PARAMETERS

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Chinese Science Bulletin 1988年第15期33卷 1241-1245页

作者：曾繁安赵玄滕礼坚王凡 Shanghai Institute of Nuclear Research Academia Sinica Sichuan University Chengdu Nanjing University I.INTRODUCTION In low energy nuclear physics the NN scattering length αand the effective range (?) are two important parameters. They have been studied experimentally and theoretically on the nucleon-meson level. In this work we want to study the

*** In low energy nuclear physics, the NN scattering length α and the effective range (?) are two important parameters. They have been studied experimentally and theoretically on the nucleon-meson level. In this work... 详细信息

关键词： nuclear-force charge-symmetry breaking low energy NN scattering parameters phase-shift

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二维超外差条纹处理技术

实验力学 2002年第Z1期17卷 53-57页

作者：姚正治史红民戴福隆金观昌清华大学工程力学系北京100084

本文从超外差式调频接受机的原理出发,提出一个适合于各种灵敏度测量的二维超外差条纹处理方法.与超外差式调频接受机的优点对应,该条纹处理方法有兼顾各种灵敏度,具有统一的中频处理与鉴相模块等优点.与其它采用条纹骨架的处理方法相比... 详细信息

本文从超外差式调频接受机的原理出发,提出一个适合于各种灵敏度测量的二维超外差条纹处理方法.与超外差式调频接受机的优点对应,该条纹处理方法有兼顾各种灵敏度,具有统一的中频处理与鉴相模块等优点.与其它采用条纹骨架的处理方法相比较,该方法实际上是直接的位相检测,其鉴相部分运用普通的phase-shift原理,因而具有测量精高度、灵敏度高的优点.此外,该方法也便于用硬件实现.

关键词：超外差二维超外差 phase-shift 空间位相鉴相器