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2023 International Applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Fang, Rongzhen Wu, Xianliang Anhui University Key Laboratory of Intelligent Computing and Signal Processing Hefei China Anhui University Department of Education of Anhui Province Hefei China

ISBN: (纸本)9781733509657

In this paper, a broadband 5G MIMO mobile antenna with a shared radiator is proposed. The working band range is 3.3-6.0GHz, covering n77, n78, n79 and WLAN 5G working bands, which can meet a large number of application scenarios of 5G mobile phones. In addition, the antenna is applied to self-decoupling, defect ground, direction diversity and other technologies and principles in the decoupling way, without the use of complex decoupling structure, to ensure that its structure is simple and easy to process, small size is suitable for today's 5G mobile phones. © 2023 Applied Computational Electromagnetics Society (ACES).

关键词： Mobile antennas

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Nonlinear dynamics in Internet congestion control model with TCP Westwood under RED

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 53-58页

作者： DING Da-wei ZHU Jie LUO Xiao-shu HUANG Lin-sheng HU Yan-jun Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China School of Electronic Engineering Guangxi Normal University Guilin 541004 China

This article develops a discrete time dynamic feedback model of a congestion control system for a simple network with TCP Westwood （TCPW） connections and a single bottleneck link with random early detection （RED） gateway. By using this model, the nonlinear dynamics of the TCPW/RED network are analyzed and its parameter sensitivities are studied. It is shown that periodic doubling bifurcation occurs when the RED control parameters or other parameters are varied. By theoretical analysis, the fixed point, the critical value of parameters and the nature of the bifurcation are determined. Moreover, by using bifurcation diagrams and Lyapunov exponent, the result of theoretical analysis is validated and the bifurcation and chaotic phenomena are numerically studied of the congestion control system with TCPW connections and RED gateway.

关键词： nonlinear system bifurcation chaos congestion control TCP Westwood RED

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Perfect plane wave injection into 3D FDTD (2, 4) scheme

Perfect plane wave injection into 3D FDTD (2, 4) scheme

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2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011

作者： Wang, Hui Huang, Zhi-Xiang Wu, Xian-Liang Wu, Lei Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781424497904

In the paper, the authors derive the method of splitting plane wave FDTD (SP-FDTD) method for initiation of plane wave sources in the total-field and scattered-field (TF/SF) formulation of 3D FDTD (2, 4) scheme. By splitting the fields on 1D auxiliary grids, the identical dispersion relation can be obtained between the 1D auxiliary grids and the 3D grids, which is also proved to be using the nature of plane wave. Using 1D auxiliary grids for introducing a plane wave, a perfect plane wave injection can be achieved at any angle forming an integer grid cell ratio. Numerical simulations also indicate the efficiency and validity of the method for FDTD (2, 4) scheme and the leakage error on the order of -300dB for double precision. © 2011 IEEE.

关键词： Numerical methods

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Numerical simulation of GPR based on 3-D high-order FDTD

Numerical simulation of GPR based on 3-D high-order FDTD

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2010 9th International Symposium on Antennas Propagation and EM Theory, ISAPE 2010

作者： Mei, Yi-Cai Huang, Zhi-Xiang Wu, Xian-Liang Ren, Xin-Gang Du, Hong-Mei Key Lab. of Intelligent Computing and Signal Processing Anhui University Ministry of Education Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781424469062

The high-order finite-difference time-domain (HO-FDTD) technique is used in the simulation of ground-penetrating radar modeling in three dimensions (3-D), which can improve accuracy and reduce the error caused by numerical dispersion effectively. To absorb waves reflected from edges we implement convolutional perfectly matched layer (CPML) absorbing boundaries. It can efficiently absorb the reflections and greatly increase the computation efficiency. The surface-based reflection and cross-hole GPR modeling are simulated, and numerical results show the efficiency of the method. ©2010 IEEE.

关键词： Ground penetrating radar systems

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A split-operator method to simulate the left hand materials

A split-operator method to simulate the left hand materials

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2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011

作者： Ren, Xin-Gang Huang, Zhi-Xiang Wu, Xian-Liang Lu, Si-Long Mei, Yi-Cai Du, Hong-Mei Wu, Lei Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781424497904

The finite difference time domain (FDTD) is a powerful method in electromagnetic simulation and also widely used in research of the metamaterials recently. In this paper a novel FDTD method based on split operator is proposed to simulate the left hand materials, and the lossless Drude dispersive model is taken into account in the proposed scheme. The split perfectly matched layers (SPML) are used to absorb outgoing wave and terminate the computational domain. Focusing and refocusing of the electromagnetic wave in target detection by using the perfect lens is validated, and the inverse Snell effect is also demonstrated. © 2011 IEEE.

关键词： Electromagnetic simulation

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Discovering Temporal User Interest on Twitter by Using Semantic Based Dynamic Interest Finding Model(TUT) 2nd

Discovering Temporal User Interest on Twitter by Using Seman...

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2017 IEEE 2nd Information Technology, Networking, Electronic and Automation Control Conference (ITNEC 2017)

作者： Rashid Abbasi Gohar Rehman Jia lee Farhad Muhammad Riaz Bin Luo School of Computer Science and Technology Anhui University College of Computer Science Chongqing University Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University

ISBN: (纸本)9781509064151;9781509064144

Social media systems are very popular in today's dynamic web. One of the famous social media systems is Twitter, in which peoples used to share their personal ideas about current issues with their friends. This work focuses on the problem of discovering a user's interest over time on twitter. Previous approaches have used to model the user topic of interest on twitter by building the profile of the users, that contain the words which can be used the user in his or her conversions with other users, but on twitter users used the noisy words which does not represent the correct topics or topic related to interest. This model has extended by a novel framework by using twitter user model. This model uses the latent topic variable to indicate the relatedness of the topic with any user. In this work, we propose a Temporal User Topic(TUT) approach which can consider the text of tweet by any user and time of the tweet. The proposed approach is used to discover topically related Users for different time periods. We also show how the interests and relationships of these users are changeovers a time period.

关键词： Topic Model User Interest Twitter Twitter-User Model Social Network Time Topic Modeling

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Simulating Maxwell-Schrodinger Equations by High-Order Symplectic FDTD Algorithm

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IEEE JOURNAL ON MULTISCALE AND MULTIPHYSICS COMPUTATIONAL TECHNIQUES 2019年 4卷 143-151页

作者： Xie, Guoda Huang, Zhixiang Fang, Ming Sha, Wei E., I Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Key Laboratory of Micro-Nano Electronic Devices and Smart Systems of Zhejiang Province College of Information Science and Electronic Engineering Zhejiang University Hangzhou China

A novel symplectic algorithm is proposed to solve the Maxwell Schrodinger (M-S) system for investigating light-matter interaction. Using the fourth-order symplectic integration and fourth-order collocated differences, M-S equations are discretized in temporal and spatial domains, respectively. The symplectic finite-difference time-domain (SFDTD) algorithm is developed for accurate and efficient study of coherent interaction between electromagnetic fields and artificial atoms. Particularly, the Dirichlet boundary condition is adopted for modeling the Rabi oscillation problems under the semiclassical framework. To implement the Dirichlet boundary condition, image theory is introduced, tailored to the high-order collocated differences. For validating the proposed SFDTD algorithm, three-dimensional numerical studies of the population inversion in the Rabi oscillation are presented. Numerical results show that the proposed high-order SFDTD(4, 4) algorithm exhibits better numerical performance than the conventional FDTD(2, 2) approach at the aspects of accuracy and efficiency for the long-term simulation. The proposed algorithm opens up a promising way toward a high-accurate energy-conservation modeling and simulation of complex dynamics in nanoscale light-matter interaction.

关键词： Maxwell Schrodinger (M-S) equations nanoscale light-matter interaction Rabi oscillation symplectic finite-difference time-domain (SFDTD)

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MedBLIP: A Multimodal Method of Medical Question-Answering Based on Fine-Tuning Large Language Model

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Computerized Medical Imaging and Graphics 2025年

作者： Lejun Gong Jiaming Yang Shengyuan Han Yimu Ji Jiangsu Key Lab of Big Data Security & Intelligent Processing School of computer science Nanjing University of Posts and Telecommunications Nanjing210023 China Institute of High Performance Computing and Bigdata Nanjing University of Posts and Telecommunications Nanjing 210023 China

Medical visual question answering is crucial for effectively interpreting medical images containing clinically relevant information. This study proposes a method called MedBLIP (Medical Treatment Bootstrapping Language-Image Pretraining) to tackle visual language generation tasks related to chest X-rays in the medical field. The method combine an image encoder with a large-scale language model, and effectively generates medical question-answering text through a strategy of freezing the image encoder based on the BLIP-2 model. Firstly, chest X-ray images are preprocessed, and an image sample generation algorithm is used to enhance the text data of doctor-patient question-answering, thereby increasing data diversity. Then, a multi-layer convolutional image feature extractor is introduced to better capture the feature representation of medical images. During the fine-tuning process of the large language generation model, a new unfreezing strategy is proposed, which is to unfreeze different proportions of the weights of the fully connected layer to adapt to the data in the medical field. The image feature extractor is responsible for extracting key features from images, providing the model with rich visual information, while the text feature extractor accurately captures the essential requirements of the user's question. Through their synergistic interaction, the model can more effectively integrate medical images and user inquiries, thereby generating more accurate and relevant output content. The experimental results show that unfreezing 31.25% of the weights of the fully connected layer can significantly improve the performance of the model, with ROUGE-L reaching 66.12%, and providing a more accurate and efficient answer generation solution for the medical field. The method of this study has potential applications in the field of medical language generation tasks. Although the proposed model cannot yet fully replace human radiologists, it plays an indispensable role

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Study of periodic dispersive structures at oblique incidence by split-field FDTD method

Study of periodic dispersive structures at oblique incidence...

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2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012

作者： Lu, Si-Long Wu, Bo Huang, Zhi-Xiang Wu, Xian-Liang Ren, Xin-Gang Mei, Yi-Cai Du, Hong-Mei Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781467321839

In this paper, the periodic structures are simulated by the split-field finite difference time domain (FDTD) method. By using this method, a set of auxiliary elements are introduced to represent the discretization of the Floquet transformed Maxwell's equations with oblique incidence. We here extend the split-field method to the study of 2D dispersive structures of Drude model combining with the Z transformation method. Some numerical experiments are presented to validate the code, and the obtained results are in good with the analytic results. © 2012 IEEE.

关键词： Finite difference time domain method

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EPAS: Efficient privacy-preserving authentication scheme for VANETs-based emergency communication

Journal of Software

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Journal of Software 2013年第8期8卷 1914-1922页

作者： Jia, Xuedan Yuan, Xiaopeng Meng, Lixia Wang, Liangmin School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang China School of Electronic Engineering and Optoelectronic Techniques NUST Nanjing China Key Laboratory of Intelligent Computing and Signal Processing MOE Anhui University Hefei China

Vehicular Ad Hoc Networks (VANETs) can provide participants with security services and entertainment information during the driving. To guarantee correct and smooth operations of VANETs, it is necessary to achieve efficient authentication with user privacy preserving. Current solutions either cannot satisfy privacy requirements, or are not efficient in message verification. Moreover, all the existing schemes are RSU-based. We, for the first time, apply VANETs to emergency communication during disaster rescue, and effective authentication scheme is proposed in accordance with the actual environment, where there is no fixed road-side unit (RSU). In this paper, we present an efficient identity based signature scheme EPAS, which satisfies conditional privacy requirements through software solution. In aspect of efficiency, both lightweight signature and batch verification are employed to provide effective authentication. Extensive theoretical and experimental analyses demonstrate the security and efficiency of EPAS in terms of privacy-preserving and low authentication delay. © 2013 ACADEMY PUBLISHER.

关键词： Vehicular ad hoc networks

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