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Coherent State Projection Operator Representation of Symplectic Transformations as a Loyal Representation of Symplectic Group

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Communications in Theoretical Physics 2002年第8期38卷 147-150页

作者： FAN Hong-yi chen Jun-Hua Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on n... 详细信息

关键词： coherent state projection operator, symplectic transformation, squeezing operator

Calculations of the Spin-Lattice Coupling Coefficients Fij and Zij for MgO:Co2+Crystal

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Communications in Theoretical Physics 2001年第10期36卷 487-490页

作者： ZHENG Wen-chen WU Shao-yi Department of Materials Science Sichuan University Chengdu 610064 China International Centre for Materials Physics The Chinese Academy of Sciences Shenyang 110015 China Department of Materials Science Sichuan University Chengdu 610064 China International Centre for Materials Physics The Chinese Academy of Sciences Shenyang 110015 China

According to a uniform and simple method of calculating spin-lattice coupling coefficients and the pert1rbation formulas of gi factors and hyperfine structure constants Ai based on the cluster approach for 3d7 ions in cubic,tetragonal and trigonal octahedral crystal fields, the spin-lattice coupling coefficients Fij (F11, Fl2, F44), Zij (Z11, Z12,Z44) and also g factor and hyperfine constant A for MgO:Co2+ are calculated by using the parameters obtained from the optical spectra without adjustable parameters. The calculated results show good agreement with the observed *** difiiculty in explaining the coeficients Fij and Zij is therefore removed.

关键词： spin-lattice coupling coefficients, electronic paramagnetic resonance, crystal- and ligand-field theory, Co2+, MgO crystal

A novel adaptive harmonic balance method with an asymptotic harmonic selection

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1887-1910页

作者： Rongzhou LIN Lei HOU yi chen Yuhong JIN N.A.SAEED Yushu chen School of Astronautics Harbin Institute of TechnologyHarbin 150001China Department of Physics and Engineering Mathematics Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Automation Biomechanicsand MechatronicsFaculty of Mechanical EngineeringLodz University of TechnologyLodz 90924Poland Mathematics Department Faculty of ScienceGalala UniversityGalala 43511Egypt

The harmonic balance method(HBM)is one of the most widely used methods in solving nonlinear vibration problems,and its accuracy and computational efficiency largely depend on the number of the harmonics *** adaptive harmonic balance(AHB)method is an improved HBM *** paper presents a modified AHB method with the asymptotic harmonic selection(AHS)*** new harmonic selection procedure selects harmonics from the frequency spectra of nonlinear terms instead of estimating the contribution of each harmonic to the whole nonlinear response,by which the additional calculation is avoided.A modified continuation method is proposed to deal with the variable size of nonlinear algebraic equations at different values of path parameters,and then all solution branches of the amplitude-frequency response are *** experiments are carried out to verify the performance of the AHB-AHS *** typical nonlinear dynamic equations with different types of nonlinearities and excitations are chosen as the illustrative *** with the classical HBM and Runge-Kutta methods,the proposed AHB-AHS method is of higher accuracy and better *** AHB-AHS method proposed in this paper has the potential to investigate the nonlinear vibrations of complex high-dimensional nonlinear systems.

关键词： harmonic balance method(HBM) adaptive harmonic balance(AHB)method harmonic selection nonlinear vibration multi-frequency excitation

Multiscale Fusion Transformer Network for Hyperspectral Image Classification

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Journal of Beijing Institute of Technology 2024年第3期33卷 255-270页

作者： Yuquan Gan Hao Zhang chen yi School of Telecommunication and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

Convolutional neural network(CNN)has excellent ability to model locally contextual ***,CNNs face challenges for descripting long-range semantic features,which will lead to relatively low classification accuracy of hyperspectral *** address this problem,this article proposes an algorithm based on multiscale fusion and transformer network for hyperspectral image ***,the low-level spatial-spectral features are extracted by multi-scale residual ***,an attention module is introduced to focus on the more important spatialspectral ***,high-level semantic features are represented and learned by a token learner and an improved transformer *** proposed algorithm is compared with six classical hyperspectral classification algorithms on real hyperspectral *** experimental results show that the proposed algorithm effectively improves the land cover classification accuracy of hyperspectral images.

关键词： hyperspectral image land cover classification multi-scale transformer

Double Enhanced Solution Quality Boosted RIME Algorithm with Crisscross Operations for Breast Cancer Image Segmentation

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Journal of Bionic Engineering 2024年第6期21卷 3151-3178页

作者： Mengjun Sun yi chen Ali Asghar Heidari Lei Liu Huiling chen Qiuxiang He Department of Computer Science and Artificial Intelligence Wenzhou UniversityWenzhou325035China School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehran***Iran College of Computer Science Sichuan UniversityChengdu610065China Department of Pathology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325000China

The persistently high incidence of breast cancer emphasizes the need for precise detection in its ***-aided medical systems are designed to provide accurate information and reduce human errors,in which accurate and effective segmentation of medical images plays a pivotal role in improving clinical *** Threshold Image Segmentation(MTIS)is widely favored due to its stability and straightforward *** when dealing with sophisticated anatomical structures,high-level thresholding is a crucial technique in identifying fine *** enhance the accuracy of complex breast cancer image segmentation,this paper proposes an improved version of RIME optimizer EECRIME,denoted as the double Enhanced solution quality Crisscross RIME *** original RIME initially conducts an efficient optimization to target promising *** double-enhanced solution quality(EESQ)mechanism is proposed for thorough exploitation without falling into local *** contrast,the crisscross operations perform a further local exploration of the generated feasible *** performance of EECRIME is verified with basic and advanced algorithms on IEEE CEC2017 benchmark ***,an EECRIME-based MTIS method in combination with Kapur’s entropy is applied to segment breast Infiltrating Ductal Carcinoma(IDC)histology *** results demonstrate that the developed model significantly surpasses its competitors,establishing it as a practical approach for complex medical image processing.

关键词： Rime optimization algorithm Double-enhanced solution quality mechanism Crisscross optimization algorithm Image segmentation Breast cancer

Microstructure and texture evolution of a near β titanium alloy Ti-7333 during continuous cooling hot deformation

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Progress in Natural Science:Materials International 2019年第1期29卷 50-56页

作者： Jiahao chen Jinshan Li Bin Tang yi chen Hongchao Kou State Key Laboratory of Solidification Processing Northwestern Polytechnical University Key Construction Laboratory of Green Forming and Equipment from Jiangsu Province Jiangsu University of Technology

The microstructure and texture evolution during continuous cooling hot deformation(CCHD) in a near β titanium alloy, named Ti-7Mo-3Nb-3Cr-3Al(Ti-7333), were investigated by using the electron backscattered diffraction(EBSD). The results indicate that the precipitation of secondary α phase was restricted by CCHD, and the morphology of primary α phase nearly had no change with the deformation and temperature drop. In contrast, βphase underwent more deformation and the grains tended to refine. This may be due to the dynamic recrystallization(DRX) of β phase, including continuous dynamic recrystallization(CDRX) and discontinuous dynamic recrystallization(DDRX). In addition, the textures of {110} , {225} and{115} transformed to {100} and {001} during CCHD. Among these, the η-fiber component of {001} was the dominant deformation texture in the deformed Ti-7333 alloy. Finally,continuous cooling has an important effect on the work hardening and softening during CCHD, contributing to the different flow behaviors at different cooling rates.

关键词： Near β titanium alloy Thermo-mechanical processing Texture Dynamic recrystallization

SSC:Gesture-based game for initial dementia examination

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1253-1258页

作者： LIU Jun-fa chen yi-qiang XIE chen GAO Wen Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100080 China College of Software Technology Zhejiang University Hangzhou 310027 China

This paper presents a novel system assisting medical dementia examination in a joyful way: the object just needs to play a popular game SSC against the computer during the examination. The SSC game’s target is to detect the player’s reacting capability, which is related closely with dementia. Our system reaches this target with some advantages: there are no temporal and spatial constraints at all. There is no cost, and it can even improve people’s mental status. Hand talk technology and EHMM gesture recognition approach are employed to realize the human computer interface. Experiments showed that this system can evaluate people’s reacting capability effectively and is helpful for initial dementia examination.

关键词： Human computer interface Hand talk Dementia Reaction capability

A multiple template approach for robust tracking of fast motion target

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Applied Mathematics(A Journal of Chinese Universities) 2016年第2期31卷 177-197页

作者： SUN Jun HE Fa-zhi chen yi-lin chen Xiao State Key Laboratory of Software Engineering School of Computer Science Wuhan UniversityWuhan 430072 China Huanggang Polytechnic College Huanggang 438002 China

Target tracking is very important in computer vision and related areas. It is usually difficult to accurately track fast motion target with appearance variations. Sometimes the tracking algorithms fail for heavy appearance variations. A multiple template method to track fast motion target with appearance changes is presented under the framework of appearance model with Kalman filter. Firstly, we construct a multiple template appearance model, which includes both the original template and templates affinely transformed from original one. Generally speaking, appearance variations of fast motion target can be covered by affine transformation. Therefore, the affine tr templates match the target of appearance variations better than conventional models. Secondly, we present an improved Kalman filter for approx- imate estimating the motion trail of the target and a modified similarity evaluation function for exact matching. The estimation approach can reduce time complexity of the algorithm and keep accuracy in the meantime. Thirdly, we propose an adaptive scheme for updating template set to alleviate the drift problem. The scheme considers the following differences： the weight differences in two successive frames; different types of affine transformation applied to templates. Finally, experiments demonstrate that the proposed algorithm is robust to appearance varia- tion of fast motion target and achieves real-time performance on middle/low-range computing platform.

关键词： Target tracking Fast motion target Multiple template match Kalman filter forecast.

The association and underlying mechanism of the digit ratio(2D:4D)in hypospadias

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Asian Journal of Andrology 2024年第4期26卷 356-365页

作者： Yu Ding Zu-Quan chen Wen-Feng Pan Hao-Jie chen Min Wu yi-Qing Lyu Hua Xie yi-chen Huang Zhong-Zhong chen Fang chen Department of Urology Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Urogenital Development Research Center Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Clinical Research Center for Hypospadias Pediatric CollegeShanghai Jiao Tong University School of MedicineShanghai 200062China.

The second-to-fourth digit(2D:4D)ratio is thought to be associated with prenatal androgen ***,the relationship between the 2D:4D ratio and hypospadias is poorly understood,and its molecular mechanism is not *** this study,by analyzing the hand digit length of 142 boys with hypospadias(23 distal,68 middle,and 51 proximal)and 196 controls enrolled in Shanghai Children’s Hospital(Shanghai,China)from December 2020 to December 2021,we found that the 2D:4D ratio was significantly increased in boys with hypospadias(P<0.001)and it was positively correlated with the severity of the *** was further verified by the comparison of control mice and prenatal low testosterone mice model obtained by knocking out the risk gene(dynein axonemal heavy chain 8[DNAH8])associated with ***,the discrepancy was mainly caused by a shift in *** characterization of a mouse model validated that low testosterone levels during pregnancy can impair the growth and development of *** mechanistic explorations revealed that during the androgen-sensitive window,the downregulation of the androgen receptor(AR)caused by low testosterone levels,as well as the suppressed expression of chondrocyte proliferation-related genes such as Wnt family member 5a(Wnt5a),Wnt5b,Smad family member 2(Smad2),and Smad3;mitochondrial function-related genes in cartilage such as AMP-activated protein kinase(AMPK)and nuclear respiratory factor 1(Nrf-1);and vascular development-related genes such as myosin light chain(MLC),notch receptor 3(Notch3),and sphingosine kinase 1(Sphk1),are responsible for the limitation of 4D growth,which results in a higher 2D:4D ratio in boys with hypospadias via decreased endochondral *** study indicates that the ratio of 2D:4D is a risk marker of hypospadias and provides a potential molecular mechanism.

关键词： androgen receptor digit ratio(2D:4D) endochondral ossification hypospadias testosterone level