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A SCREW DISLOCATION IN A THREE-PHASE COMPOSITE CYLINDER MODEL WITH INTERFACIAL RIGID LINES 被引量:2
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作者 Fang Qihong Liu Youwen Jiang Chiping 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第4期283-294,共12页
The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex mul... The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex multiply connected region is developed, with which explicit series form solutions of the complex potentials in the matrix, and the interphase layer and inclusion regions are derived. Based on the complex potentials, the image force on the screw dislocation is then calculated by using the Peach-Koehler formula. The equilibrium position of the dislocation is discussed in detail for various rigid line geometries, interphase layer thicknesses and material property combinations. The main results show that the interracial rigid lines exert a significant perturbation effect on the motion of the screw dislocation near the circular inclusion surrounded by an interphase layer. 展开更多
关键词 screw dislocation interfacial rigid lines interphase layer complex potential method image force
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Imaging Ultrafast Plasmon Dynamics within a Complex Dolmen Nanostructure Using Photoemission Electron Microscopy
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作者 秦将 郎鹏 +5 位作者 季博宇 N.K.Alemayehu 陶海岩 高勋 郝作强 林景全 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期82-86,共5页
We report direct nanoscale imaging of ultrafast plasmon in a gold dolmen nanostructure excited with the 7is laser pulses by combining the interferometric time-resolved technology with the three-photon photoemission el... We report direct nanoscale imaging of ultrafast plasmon in a gold dolmen nanostructure excited with the 7is laser pulses by combining the interferometric time-resolved technology with the three-photon photoemission electron microscopy (PEEM). The interferometric time-resolved traces show that the plasmon mode beating pattern appears at the ends of the dimer slabs in the dolmen nanostructure as a result of coherent superposition of multiple localized surface plasmon modes induced by broad bandwidth of the ultrafast laser pulses. The PEEM measurement further discloses that in-phase of the oscillation field of two neighbor defects are surprisingly observed, which is attributed to the plasmon coupling between them. Furthermore, the control of the temporal delay between the pump and probe laser pluses could be utilized for manipulation of the near-field distribution. These findings deepen our understanding of ultrafast plasmon dynamics in a complex nanosystem. 展开更多
关键词 of on as in Imaging Ultrafast Plasmon Dynamics within a Complex Dolmen Nanostructure Using Photoemission Electron Microscopy that ITR
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A Fast and Accurate Method for the Analysis of Multi-conductor Coplanar Wave-Guide Transmission Lines
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作者 Ting Chen Xia Zhou Ying Li 《Advances in Manufacturing》 2000年第3期220-224,共5页
This paper introduces the complex image concept, and uses the method to analyze multi conductor coplanar waveguides. The method of spectral domain Green's function for modeling point charge and line charge struct... This paper introduces the complex image concept, and uses the method to analyze multi conductor coplanar waveguides. The method of spectral domain Green's function for modeling point charge and line charge structures is studied, in which Chebyshev polynomials are used as basis functions to solve the integral equation by the Galerkin's method. It is believed that the complex method has the features of accuracy and rapid convergence, and it is possible to make the technique useful as CAD tool for coplanar waveguide design. 展开更多
关键词 multiconductor coplanar waveguide complex image method Galerkin's method
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Adapting Nanotech Research as Nano-Micro Hybrids Approach Biological Complexity,A Review
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作者 Sascha Vongehr Shaochun Tang Xiangkang Meng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第5期387-401,共15页
Today's emergence of nano-micro hybrid structures with almost biological complexity is of fundamental interest. Our ability to adapt intelligently to the challenges has ramifications all the way from fundamentally ch... Today's emergence of nano-micro hybrid structures with almost biological complexity is of fundamental interest. Our ability to adapt intelligently to the challenges has ramifications all the way from fundamentally changing research itself, over applications critical to future survival, to posing globally existential dangers. Touching on specific issues such as how complexity relates to the catalytic prowess of multi-metal compounds, we discuss the increasingly urgent issues in nanotechnology also very generally and guided by the motto 'Bio Is Nature's Nanotech'. Technology belongs to macro-evolution; for example integration with artificial intelligence (AI) is inevitable. Darwinian adaptation manifests as integration of complexity, and awareness of this helps in developing adaptable research methods that can find use across a wide range of research. The second half of this work reviews a diverse range of projects which all benefited from 'playful' programming aimed at dealing with complexity. The main purpose of reviewing them is to show how such projects benefit from and fit in with the general, philosophical approach, proving the relevance of the 'big picture' where it is usually disregarded. 展开更多
关键词 Complex hybrid structures Catalysis Macro-evolution Optimization image analysis Simulation Statistical analysis Error analysis Critique of technology
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A Method to Estimate the Steganographic Capacity in DCT Domain Based on MCUU Model
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作者 MAO Jiafa HUANG Yanhong +3 位作者 NIU Xinxin XIAO Gang ZHU Linan SHENG Weiguo 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第4期283-290,共8页
In order to estimate maximum steganographic capacity of discrete cosine transform(DCT) domain in JPEG image, this paper presents a method based on the maximize capacity under undetectable model(MCUU). We analyze t... In order to estimate maximum steganographic capacity of discrete cosine transform(DCT) domain in JPEG image, this paper presents a method based on the maximize capacity under undetectable model(MCUU). We analyze the relation between steganographic capacity and affecting factors(image size, steganography operator, loading band, embedding intensity and image complexity). Then we design a steganography analyzer architecture and a steganographic algorithm which can dynamically increase the steganographic capacity. Compared with other methods of embedding capacity estimation in DCT domain, the proposed methods utilizes general steganalysis methods rather than one specific steganalysis technique and takes five essential factors into account, which improves the commonality and comprehensiveness of capacity estimation, respectively. The experimental results show that steganographic capacity for quantization index modulation(QIM) is almost twice that of spread spectrum(SS) based on MCUU model. 展开更多
关键词 maximize capacity under undetectable(MCUU) model steganographic capacity steganography steganalysis image complexity
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Functional organization of complex brain networks modulated by acupuncture at different acupoints belonging to the same anatomic segment 被引量:12
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作者 CHEN Shang-jie MENG Lan +6 位作者 YAN Hao BAI Li-jun WANG Fang HUANG Yong LI Jian-ping PENG Xu-ming SHI Xue-min 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第15期2694-2700,共7页
Background Noninvasive functional magnetic resonance imaging (fMRI) techniques have opened a "window" into the brain, allowing us to investigate the anatomical and physiological function involving acupuncture need... Background Noninvasive functional magnetic resonance imaging (fMRI) techniques have opened a "window" into the brain, allowing us to investigate the anatomical and physiological function involving acupuncture needling. Imaging its sustained effect rather than acute effect on the brain networks may further help elucidate the mechanisms by which acupuncture achieves its therapeutic effects. In this study, we aimed to investigate the functional brain networks during the post-resting state following acupuncture at KI3 in comparison with acupuncture at GB40. Methods Needling at acupoints GB40 and KI3 was performed in twelve subjects. Six minutes of scanning at rest were adopted before and after acupuncture at different acupoints. Then we divided the whole brain into 39 regions and constructed functional brain networks during the post-acupuncture resting states (PARS). Results For direct comparisons, increased correlations during post-resting state following acupuncture at KI3 compared to resting state (RS) were primarily located between the dorsolateral prefrontal cortex (DLPFC) and post temporal cortex, ventromedial prefrontal cortex (vmPFC) and post temporal cortex. These brain regions were all cognitive-related functions. In contrast, the increased connections between the anterior insula and temporal cortex mainly emerged following acupuncture at GB40 compared with the RS. Conclusions The present study demonstrates that acupuncture at different acupoints belonging to the same anatomic segment can exert different modulatory effects on the reorganizations of post-acupuncture RS networks. The heterogeneous modulation patterns between twoconditions may relate to the functional specific modulatory effects of acupuncture. 展开更多
关键词 ACUPUNCTURE functional magnetic resonance imaging complex brain networks
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Efficient approach and application of the Green's functions in spatial domain in multilayered media
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作者 ZHANG Min LI LeWei +1 位作者 LI LiangChao WU ZhenSen 《Science in China(Series F)》 2008年第4期394-407,共14页
Based on the dipole source method, all components of the Green's functions in spectral domain are restructured concisely by four basis functions, and in terms of the two-level discrete complex image method (DCIM) w... Based on the dipole source method, all components of the Green's functions in spectral domain are restructured concisely by four basis functions, and in terms of the two-level discrete complex image method (DCIM) with the high order Sommerfeld identities, an efficient algorithm for closed-form Green's functions in spatial domain in multilayered media is presented. This new work enjoys the advantages of the surface wave pole extraction directly carried out by the generalized integral path without troubles of that all components of Green's function in spectral domain should be reformed respectively in transmission line network analogy, and then the Green's functions for mixed-potential integral equation (MPIE) analysis in both near-field and far-field in multilayered media are obtained. In addition, the curl operator for coupled field in MPIE is avoided conveniently. It is especially applicable and useful to characterize the electromagnetic scattering by, and radiation in the presence of, the electrically large 3-D objects in multilayered media. The numerical results of the S-parameters of a microstrip periodic bandgap (PBG) filter, the radar cross section (RCS) of a large microstrip antenna array, the characteristics of scattering, and radiation from the three-dimensional (3-D) targets in multilayered media are obtained, to demonstrate better effectiveness and accuracy of this technique. 展开更多
关键词 Green's functions in spatial domain mixed potential integral equation multilayered media discrete complex image method sommerfeld identity
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FIFA-Fast Interpolation and Filtering Algorithm for Calculating Dyadic Green’s Function in the Electromagnetic Scattering of Multi-Layered Structures
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作者 Tiejun Yu Wei Cai 《Communications in Computational Physics》 SCIE 2006年第2期229-260,共32页
The dyadic Green’s function in multi-layer structures for Maxwell equations is a key component for the integral equation method,but time consuming to calculate.A novel algorithm,the Fast Interpolation and Filtering A... The dyadic Green’s function in multi-layer structures for Maxwell equations is a key component for the integral equation method,but time consuming to calculate.A novel algorithm,the Fast Interpolation and Filtering Algorithm(FIFA),for the calculation of the dyadic Green’s function in multi-layer structures is proposed in this paper.We discuss in specific details,ready for use in practical calculations of scattering in layer media,how to apply FIFA to calculate various components of the dyadic Green’s function.The algorithm is based on two techniques:interpolation of Green’s function both in the spectral domain and spatial domain,and low pass filter window based acceleration.Compared to the popular Complex Image Method(CIM),FIFA provides the same speed and overcomes several difficulties associated with CIM while being more general and robust.Specifically,there are no limitations on the frequency range,the number of layers in the structure and the type of Green’s functions to be calculated,and moreover,no need to extract surface wave poles from the spectral form of the Green’s function.Numerical results are given to demonstrate the efficiency and robustness of the proposed method. 展开更多
关键词 Fast interpolation and filtering algorithm(FIFA) complex image method(CIM) low pass filter window(LPFW) interpolation table(IT) electromagnetic(EM)
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