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A new ultra-wideband MIMO antenna based on metamaterials for 5G

A new ultra-wideband MIMO antenna based on metamaterials for...

International Conference on Numerical Electromagnetic Modeling and Optimization for RF, Microwave, and Terahertz Applications (NEMO)

作者： Yaqin Li Shijie Huang Liang Zhang Xianliang Wu Key Laboratory of Intelligent Computing & Signal Processing Anhui University Hefei China AnHui Province Key Laboratory of simulation and design for Electronic informationKey Laboratory of Intelligent Computing & Signal Processing Hefei Normal university Hefei China

ISBN: (数字)9781728169668

ISBN: (纸本)9781728169675

An improved ultra-wideband low-coupling MIMO antenna based on a metamaterial periodic structure frequency-selective surface wide slot antenna is derived from the basic -shaped resonant ring. The antenna can be implemented without loading any parasitic branches low coupling and high gain, the relative bandwidth exceeds the international standard of ultra-wideband (20%), and at the same time uses metamaterials whose electromagnetic characteristics can be artificially changed as a medium, the element antennas are arranged in a 9 × 9 array and processed at 90° In order to achieve the goal of miniaturization, the structure is more compact. The 37 GHz MIMO antenna with a structure size of 108 mm × 104 mm × 1 mm working in the 5G millimeter wave band is simulated. The results show that the peak gain of the unit antenna bandwidth is 10 dB, the impedance bandwidth is 21%, and the isolation is less than 20 dB. It meets the expected performance requirements of ultra-wideband, low coupling, miniaturization and other performances, and will have important applications in the area of 5G mobile communications.

关键词： Slot antennas Bandwidth Ultra wideband antennas Metamaterials Loaded antennas Antenna arrays Periodic structures

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Effects of Wall Emissivity on Aerodynamic Heating in Scramjets

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Fluid Dynamics & Materials Processing 2020年第6期16卷 206-216页

作者： Yue Zhou Pengfei Ju School of Aeronautical Science and Technology Beihang UniversityBeijing100191China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology) Tianjin300384China

The effects of the wall emissivity on aerodynamic heating in a scramjet are *** supersonic turbulent combustion flow including radiation is solved in the framework of a decoupled strategy where the flow field is determined first and the radiation field *** particular,a finite difference method is used for solving the flow while a DOM(iscrete ordinates method)approach combined with a WSGGM(weighted sum of gray gases)model is implemented for radiative *** nonreactive turbulent channel flows are examined for a DLR hydrogen fueled scramjet changing parametrically the wall *** results indicate that the wall radiative heating rises greatly with increasing the wall *** the wall emissivity rises,the radiative source and total absorption increase,while the incident radiation decreases ***,although the radiative heating can reach a significant level,its contribution to the total aerodynamic heating is relatively limited.

关键词： Scramjet aerodynamic heating wall emissivity radiation

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Hamiltonian Dynamics and Targeted Energy Transfer of a Grounded Bistable Nonlinear Energy Sink

SSRN

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SSRN 2022年

作者： Li, Shuangbao Zhou, Xinxing Chen, Jianen Research Institute of Science and Technology Civil Aviation University of China Tianjin300300 China College of Science Civil Aviation University of China Tianjin300300 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China

A two-degree-of-freedom nonlinear mechanical system describing a damped linear oscillator weakly coupled to a lightweight grounded bistable nonlinear energy sink is proposed to investigate the targeted energy transfer (TET) under asymmetric local nonlinear potentials. The Bogdanov-Takens bifurcations of equilibria are discussed to reflect the bistable and asymmetric characteristics of the system. Through projections of isoenergetic manifolds, the topological features of the Hamiltonian dynamics under $1:1$ internal resonance have been investigated, which induces conditions for energy localization and exchange. In the general case, the topological features of the Hamiltonian dynamics related to the nonlinear normal modes (NNMs) are classified by the Poincare map, the relations between the NNMs and the Hamiltonian dynamics have been interpreted through the frequency energy plots. The results show that introducing the asymmetric characteristics may enhance the TET and realize the complete TET. © 2022, The Authors. All rights reserved.

关键词： Degrees of freedom (mechanics)

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A method of terminology alignment in Historical Books based on the correspondence between Pivot language and position

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Journal of Physics: Conference Series 2021年第1期1883卷

作者： Xingchen Xie Xiaoting Wu Xiaopeng Wei Chao Che Key Laboratory of Advanced Design and Intelligent Computing Dalian University Dalian Liaoning 116622 China

In view of the most difficult problem of terminology translation in the translation of historical books, this paper extracts term translation pairs from bilingual parallel corpus as a reference to improve the quality and efficiency of the translation of historical books. However, the small size of the corpus of historical books leads to poor word alignment, which brings a large number of errors to term alignment. At the same time, the special grammar of ancient Chinese will also affect term alignment. In order to solve the above two problems, this paper proposes a method of term alignment of historical books based on pivot language and position correspondence. This method introduces modern Chinese as the pivot language, makes use of the position correspondence between modern Chinese and English terms in sentences, and uses the sliding window method to generate candidate term pairs, which avoids the influence of word alignment errors on term alignment. In addition, if we first align to modern Chinese, the ancient Chinese terminology will complete the omitted characters in modern Chinese and replace the false characters, so as to avoid the influence of the special usage in ancient Chinese on the term alignment. The experimental results in Historical Records show that the accuracy of this method is slightly better than that of the method based on word alignment, which verifies the effectiveness of this method without word alignment.

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Clustering Interval and Triangular Granular Data: Modeling, Execution, and Assessment

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IEEE Transactions on Neural Networks and Learning Systems 2024年第6期36卷 10000-10014页

作者： Yiming Tang Wenbin Wu Witold Pedrycz Jianwei Gao Xianghui Hu Zhaohong Deng Rui Chen Anhui Province Key Laboratory of Affective Computing and Advanced Intelligent Machine School of Computer and Information Hefei University of Technology Hefei China Department of Electrical and Computer Engineering University of Alberta Edmonton AB Canada School of Computer and Information Hefei University of Technology Hefei China Faculty of Automatic Control Electronics and Computer Science Silesian University of Tecghnology Gliwice Poland Research Center of Performance and Productivity Analysis Istinye University Istanbul TÃrkiye School of Computer Science and Engineering Southeast University Nanjing China School of Artificial Intelligence and Computer Jiangnan University Wuxi Jiangsu China

In current granular clustering algorithms, numeric representatives were selected by users or an ordinary strategy, which seemed simple; meanwhile, weight settings for granular data could not adequately express their structural characteristics. Aiming at these problems, in this study, a new scheme called a granular weighted kernel fuzzy clustering (GWKFC) algorithm is put forward. We propose the representative selection and granularity generation (RSGG) algorithm enlightened by the density peak clustering (DPC) algorithm. We build interval and triangular granular data on the strength of numeric representatives obtained by RSGG under the principle of justifiable granularity (PJG), in which we establish some combinations of functions and boundary constraints and prove their properties. Furthermore, we present a novel distance formula via the kernel function for granular data and design new weights to affect the coverage and specificity of granular data. In addition, based upon these factors, we come up with the GWKFC algorithm of granular clustering, and its performance with different granularity is assessed. To sum up, a macro framework involving granular modeling, granular clustering, and assessment has been set up. Lastly, the GWKFC algorithm and ten other granular clustering algorithms are compared by experiments on some artificial and UCI datasets together with datasets with large data or those of high dimensionality. It is found that the GWKFC algorithm can provide better granular clustering results by contrast with other algorithms. The originality is embodied as follows. First, we improve the previous density radius and present the RSGG algorithm to acquire numeric representatives. Second, we propose a new strategy to determine granular data boundaries and further obtain novel weights enlightened by the idea of volume. Lastly, we employ the kernel function to calculate the distance between granular data, which has a stronger spatial division ability than the pr

关键词： Clustering algorithms Data models Computational modeling Numerical models Kernel Phase change materials Granular computing Uncertainty Fuzzy sets Noise

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Finite element analysis of biomechanical effects of oversized total talar prosthesis and collateral ligament reconstruction on total talar replacement

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Foot and Ankle Surgery 2025年

作者： Li, Hao Xie, Haitao Li, Yuanqiang Chen, Wan Xie, Haiqiong Cai, Xu Wei, Kai Key Laboratory of Advanced Design and Simulation Techniques for Special Equipment Ministry of Education Hunan University Changsha China XingGuo people's Hospital Jiangxi China School of Advanced Manufacturing Engineering Chongqing University of Posts and Telecommunications Chongqing China Chongqing Institute of Bio-Intelligent Manufacturing Chongqing China Sports Medicine Center First Affiliated Hospital of The Army Medical University Chongqing China Department of Orthopedics The Third Xiangya Hospital of Central South University Department of Spinal Surgery Hunan Xiangya Boai Rehabilitation Hospital Changsha China

Background: Total talar replacement (TTR) using a personalized customized total talar prosthesis (TTP) is an emerging and promising surgical option for the treatment of ankle problems. However, how to solve ankle instability after total talar replacement, and the influence of related solutions on foot biomechanics has not been investigated. Methods: Our preliminary studies have found that enlarging a personalized total talar prosthesis (TTP0) by 1.5 % along the coronal axis (TTP-FP1.5) and reconstructing the anterior talofibular ligament (ATFL) significantly can enhance ankle stability. However, there is a lack of insight into the effect of the two options on biomechanics. Consequently, this work constructed anatomically detailed finite element models of the foot, including an intact model and four surgical models, including replacement of TTP0, replacement of TTP-FP1.5, and two models of TTP-coupled ATFL reconstruction. Biomechanical differences were evaluated by numerical simulation of a balanced-standing and three characteristic instants of the stand phase. Results: Changes in plantar pressure distribution, joint contact pressure and force transmission, von Mises stress on bone, and prosthesis stress were predicted and analyzed. It was found that significant changes in foot biomechanics occurred after TTP-FP1.5 replacement compared to TTP0 replacement. In contrast, no ligament reconstruction versus ATFL reconstruction exerts a minor effect on biomechanics. Conclusion: The findings indicate that the shape of the prosthesis is the primary factor affecting foot biomechanics after total talar replacement. In contrast, reconstruction of the ATFL has only a minimal effect on the biomechanics of the foot. The above findings will provide a solid basis for the improvement of TTR surgical plans in clinical. © 2025 European Foot and Ankle Society

关键词： Ankle stability Biomechanics Finite element analysis Total talar replacement

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The Effect of the Number of Sensor Coils on Sensitivity in Electromagnetic Tomography 4

The Effect of the Number of Sensor Coils on Sensitivity in E...

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4th International Symposium on Image computing and Digital Medicine, ISICDM 2020

作者： Xu, Siqi Zhao, Qian Li, Liu Li, Nan Tan, Wenjun College of Physical Science and Technology Shenyang Normal University Shenyang China Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen China Key Laboratory of Intelligent Computing in Medical Image Ministry of Education Northeastern University Shenyang China

ISBN: (纸本)9781450389686

Electromagnetic tomography (EMT) is a process tomography based on the principle of electromagnetic induction. It has the advantages of non-intrusive, non-contact and low harm. In the process of image reconstruction, the sensitivity matrix reflects the influence of tiny disturbance on the measured value, which is an important index of image quality. Base on the traditional "O"sensor array structure in this article, Comsol Multiphysics finite element simulation software is used to divide the measured field into several tiny elements. A simulated perturbation method is used to investigate the effect of the number of EMT sensors' midline coils on sensitivity. The sensitivity matrix of sensor arrays with 4 coils ,8 coils ,12 coils ,16 coils and 20 coils is compared by using the method of separation variables. The sensitivity matrix of different coils is imaged by Matlab software. Through comparative analysis, it is concluded that the sensitivity band shape of the coil in the same position is same in different models. All of them are distributed along the arc type between the excitation and detection coils, which presents the middle strong and gradually weakens to the outside. With the increase of the number of coils, the sensitivity band is widened, but the sensitivity value of the central part is slightly weakened. According to this characteristic, it lays a foundation for the practical application of EMT technology and image reconstruction. © 2020 Owner/Author.

关键词： Image reconstruction

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A Protein Embedding Model for Drug Molecular Screening

A Protein Embedding Model for Drug Molecular Screening

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International Conference on Big Data and Smart computing (BIGCOMP)

作者： Chao Che Min Zhu Yongjun Zhu Qiang Zhang Dongsheng Zhou Bin Wang Key Laboratory of Advanced Design and Intelligent Computing Ministry of Education Dalian University Dalian China Department of Library and Information Science Sungkyunkwan University Seoul Republic of Korea

ISBN: (数字)9781728160344

ISBN: (纸本)9781728160351

Application of machine learning method in new drug development can greatly shorten the process of experimental discovery and reduce the risk of clinical failure. However, the feature extraction of proteins sequence is very difficult due to the large dimension. To this end, we propose a Protein Embedding Model(PEM) for drug molecular screening to predict the interaction between proteins and small molecules. Specifically, PEM first classifies 20 kinds of amino acids into 6 categories to reduce the dimension and learns the representation of protein borrowing the idea of word embedding. Then the model uses multiple imputation to fill the physical and chemical properties of small molecule compounds. Finally, the model uses LightGBM model to predict the affinity value Ki between proteins and small molecules. Experiments show that the model can effectively extract the features of proteins and small molecules and outperforms other traditional methods on the data provided by a drug discovery and development company.

关键词： Amino acids Feature extraction Drugs Protein sequence Chemicals Compounds

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Segmentation of pulmonary vessels based on MSFM method

Segmentation of pulmonary vessels based on MSFM method

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International Conference on e-health Networking, Applications and Services (HealthCom)

作者： Xiaowei Wang Liying Cheng Danyang Huang Xuanshuang Gao Daili Liang Liuye He Zhimei Zhang Nan Li Wenjun Tan School of Physical Science and Technology Shenyang Normal University Shenyang China Chinese Academy of Sciences Shenzhen Institutes of Advanced Technology China Key Laboratory of Intelligent Computing in Medical Image Northeastern University Shenyang China

ISBN: (数字)9781728162676

ISBN: (纸本)9781728162683

Accurate segmentation of pulmonary blood vessels from CT images is of great significance for lung disease detection and segmentation of other lung structures. Manual segmentation is difficult to accurately segment vascular tissue for various reasons. Therefore, in view of the existing problems and shortcomings of the existing lung vessel segmentation method, a more efficient lung vessel segmentation algorithm is proposed, that is, the multi-template fast marching method (MSFM algorithm). Firstly, it used the hole filling and maximum inter-class variance algorithm for preprocess. In the process, the lung parenchyma is extracted from the chest CT, and then the lung blood vessels are extracted in the lung parenchymal area using the MSFM algorithm. In the extraction process, the threshold and gradient are used to limit the progress of the process and the lung blood vessels are more accurately segmented. Through experimental verification, the accuracy of lung blood vessel segmentation based on MSFM algorithm is improved.

关键词： Image segmentation Computed tomography Pulmonary diseases Lung Surface morphology Blood vessels Biomedical imaging

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Speech Emotion Recognition Based on Image Enhancement 14

Speech Emotion Recognition Based on Image Enhancement

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14th IEEE International Conference on intelligent Systems and Knowledge Engineering, ISKE 2019

作者： Wang, Dongyan Dong, Jing Zhou, Dongsheng Wei, Xiaopeng Zhang, Qiang Ministry of Education Dalian University Key Laboratory of Advanced Design and Intelligent Computing Dalian China Dalian University of Technology School of Computer Science and Technology Dalian China

ISBN: (纸本)9781728123486

The performance of an emotion recognition system is determined by the quality of emotional features. In this paper, we propose a feature optimization algorithm based on image enhancement and present a convolutional recurrent model to realize emotional recognition of natural speech. For three-dimensional (3-D) log-Mel spectrum and 3-D spectrogram features, the fast gamma transformation with an adaptive threshold is adopted for feature enhancement to make full use of the dynamic characteristics of non-stationary speech signals. Meanwhile, the model combining Convolutional Neural Network (CNN) with the rectangular kernels and Long Short-Term Memory (LSTM) is used to complete speech emotion recognition tasks. Experiments are carried out on two public emotional datasets, and results demonstrate the good generalization ability and recognition performance of our proposed model. © 2019 IEEE.

关键词： Image enhancement

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