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(2+1)-Dimensional Spatial Localized Modes in Cubic-Quintic Nonlinear media with the PT-Symmetric Potentials

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Communications in Theoretical Physics 2015年第7期64卷 71-80页

作者：陈翼翔徐周翔蒋云峰史进徐方迁 School of Electronics Information Zhejiang University of Media and Communications Institute of digital media and Communication Technology Zhejiang University of Media and Communications Department of Physics Institute of Optics Zhejiang University Network Center Zhejiang Police College

We obtain exact spatial localized mode solutions of a(2+1)-dimensional nonlinear Schr¨odinger equation with constant diffraction and cubic-quintic nonlinearity in PT-symmetric potential, and study the linear stability of these solutions. Based on these results, we further derive exact spatial localized mode solutions in a cubic-quintic medium with harmonic and PT-symmetric potentials. Moreover, the dynamical behaviors of spatial localized modes in the exponential diffraction decreasing waveguide and the periodic distributed amplification system are investigated.

关键词： 2D spatial localized modes PT-symmetric potential

E-Shop Transshipment Selection Evaluation Based on Cloud Model

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Journal of Shanghai Jiaotong university(Science) 2018年第5期23卷 643-649页

作者： LIU Sainan College of digital media and artistic design Hangzhou Dianzi UniversityHangzhou 310018China

In e-commerce, a critical problem is how to transship the products between different e-shops to lessen the risk of out of stock, especially in network shopping mall of China. Most of importance is how to select the optimal one in the waiting list of e-shops to make the transshipment economical. However, many factors that influence the effect of transshipment are uncertain and fuzzy, such as customer demand, product price and inventory level. Based on the cloud model theory, a novel method for evaluation of e-shop transshipment selection in the same network shopping mall is proposed to solve the problem. The factors that influence the transshipment effect are discussed in detail. An example of selecting the optimal e-shop to transship products to the out of stock e-shop is given on the basis of the steps of our evaluation calculation. Finally, the result shows that it can effectively optimize transshipment in online shopping economically.

关键词： transshipment online shopping evaluation cloud model

Key technologies of light field capture for 3D reconstruction in microscopic scene

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Science China(Information Sciences) 2010年第10期53卷 1917-1930页

作者： WANG Yu, JI XiangYang & DAI QiongHai Broadband Networks & digital media Lab of Automation Department, Tsinghua University, Beijing 100084, China Broadband Networks & digital media Lab of Automation Department Tsinghua University Beijing China

Light field capture for 3D reconstruction in microscopic scene is a very promising and useful technology, which can be extensively applied to life sciences, medicine, materials science, etc. This paper summarizes the key technologies in the evolution of microscopes for capturing 3D information, including wavefrontreconstruction, holography, fluorescence, tomography and so on. To give in-depth insights into them, detailed analyses and comparisons are provided. Finally, some future potential work in terms of light field capture and its application are discussed at length.

关键词： light field 3D reconstruction microscopy

Polling Algorithm Based on Traffic Burst Characteristics of Broadband Wireless Access Systems

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Journal of Shanghai Jiaotong university(Science) 2011年第4期16卷 429-435页

作者：李秀媛李炜吴晓娟张云峰 School of Computer Science and Technology Shandong Economy University School of Information Science and Engineering Shandong University Shandong Provincial Key laboratory of digital media Technology

In this paper,we propose a novel polling algorithm to decrease the number of idle slots and collission slots during the polling cycle by evaluating the bandwidth request of the subscribe stations(SSs) in the next polling cycle for broadband wireless access(BWA) *** firstly analyze the feature of silent time intervals and deduce the Hurst index which symbolizes the degree of self-similarity and long-relative *** we represent the inactive OFF time intervals by the Pareto model and estimate the shape parameterαby the group measured *** we can evaluate the transmission probability of a silent SS before the next polling cycle. By this algorithm,we can find the optimal transmission opportunities for the base station(BS) to achieve the least collision or void timeslots in order to achieve the largest bandwidth *** theoretical analysis and simulation results show that this polling algorithm can improve the performance for BWA system.

关键词： broadband wireless access(BWA) systems polling algorithm bandwidth allocation self-similarity

Formula for computing knots with minimum stress and stretching energies

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Science China(Information Sciences) 2018年第5期61卷 171-185页

作者： Xuemei LI Fan ZHANG Guoning CHEN Caiming ZHANG School of Computer Science and Technology Shandong University School of Computer Science and Technology Shandong Technology and Business University Department of Computer Science University of Houston Shandong Provincial Key laboratory of digital media Technology

Computing knots for a given set of data points in a plane is one of the key steps in the construction of fitting curves with high precision. In this study, a new method is proposed for computing a parameter value(knot) for each data point. With only three adjacent consecutive data points, one may not determine a unique interpolation quadratic polynomial curve, which has one degree of freedom(a variable). To obtain a better curve, the stress and stretching energies are used to optimize this variable so that the quadratic polynomial curve has required properties, which ensure that when the three consecutive points are co-linear, the optimal quadratic polynomial curve constructed is the best. If the position of the mid-point of the three points lies between the first point and the third point, the quadratic polynomial curve becomes a linear polynomial curve. Minimizing the stress and stretching energies is a time-consuming task. To avoid the computation of energy minimization, a new model for simplifying the stress and stretching energies is presented. The new model is an explicit function and is used to compute the knots directly, which greatly reduces the amount of computation. The knots are computed by the new method with minimum stress and stretching energies in the sense that if the knots computed by the new method are used to construct quadratic polynomial,the quadratic polynomial constructed has the minimum stress and stretching energies. Experiments show that the curves constructed using the knots generated by the proposed method result in better interpolation precision than the curves constructed using the knots by the existing methods.

关键词： parameter stress and stretching energies polynomial precision curve construction

Hyperspectral anomaly detection via memory‐augmented autoencoders

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1274-1287页

作者： Zhe Zhao Bangyong Sun Faculty of Printing Packaging Engineering and Digital Media TechnologyXi'an University of TechnologyXi'anChina Norwegian Colour and Visual Computing laboratory Norwegian University of Science and TechnologyGjovikNorway

Recently,the autoencoder(AE)based method plays a critical role in the hyperspectral anomaly detection ***,due to the strong generalised capacity of AE,the abnormal samples are usually reconstructed well along with the normal background ***,in order to separate anomalies from the background by calculating reconstruction errors,it can be greatly beneficial to reduce the AE capability for abnormal sample reconstruction while maintaining the background reconstruction performance.A memory‐augmented autoencoder for hyperspectral anomaly detection(MAENet)is proposed to address this challenging ***,the proposed MAENet mainly consists of an encoder,a memory module,and a ***,the encoder transforms the original hyperspectral data into the low‐dimensional latent ***,the latent representation is utilised to retrieve the most relevant matrix items in the memory matrix,and the retrieved matrix items will be used to replace the latent representation from the ***,the decoder is used to reconstruct the input hyperspectral data using the retrieved memory *** this strategy,the background can still be reconstructed well while the abnormal samples *** conducted on five real hyperspectral anomaly data sets demonstrate the superiority of the proposed method.

关键词： anomaly detection hyperspectral images memory autoencoder

LotusMenu: a 3D menu using wrist and elbow rotation inspired by Chinese traditional symbol

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Science China(Information Sciences) 2021年第10期64卷 242-244页

作者： Fei LYU Yujie LIU Jin HUANG Zhaolin ZHANG School of digital media and Design Arts Beijing University of Posts and Telecommunications Beijing Key laboratory of Network System and Network Culture Beijing University of Posts and Telecommunications State Key laboratory of Computer Science Institute of Software Chinese Academy of Sciences

Three-dimensional rotation, including pitching, yawing and rolling, is an important gesture in 3D interaction, with the potential to extend the selection capability in large screen interaction system. For 3D rotation interaction, researchers indicated the design space of pen tilt [1] and wrist tilt as input modality [2, 3]. However, the combination of freehand 3D rotation gesture has not been fully utilized for menu control.

关键词： interaction 3D menu freehand gesture selection technology 3D rotation

An optimal quality adaptation mechanism for end-to-end FGS video transmission

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 119-124页

作者： ER Gui-hua Broadband Networks & digital media laboratory Department of Automation Tsinghua UniversityBeijing 100084China

In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS)stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quality variation and increasing available bandwidth usage rate. Under the condition that the whole bandwidth evolution is known, we design an optimal algorithm to select layer. When the knowledge of future bandwidth is not available, we also develop an online algorithm based on the optimal algorithm. Simulation showed that both optimal algorithm and online algorithm can offer smoothed video quality evolution.

关键词： MPEG-4 fine granular scalability (FGS), Video streaming, Transmission, Quality adaptation

Large margin deep embedding for aesthetic image classification

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Science China(Information Sciences) 2020年第1期63卷 229-231+259-264页

作者： Guanjun GUO Hanzi WANG Yan YAN Liming ZHANG Bo LI Fujian Key laboratory of Sensing and Computing for Smart City School of Information Science and EngineeringXiamen University Faculty of Science and Technology University of Macau Beijing Key laboratory of digital media School of Computer Science and EngineeringBeihang University

Dear editor,The problem of aesthetic image classification has attracted much attention during the past few years. The recently proposed methods [1–4] based on the deep convolutional neural network (CNN)[5,6]have achi... 详细信息

关键词： net CNN image Large margin deep embedding for aesthetic image classification