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Non-asymptotic Error Bound for Optimal Prediction of Function-on-Function Regression by RKHS Approach

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Acta Mathematica Sinica,English Series 2022年第4期38卷 777-796页

作者： Hong Zhi TOng Ling fang HU Michael ng School of Statistics University of International Business and EconomicsBeijing 100029P.R.China Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong KongP.R.China Department of Mathematics The University of Hong KongPokfulamHong KongP.R.China

In this paper,we study and analyze the regularized least squares for function-on-function regression *** our model,both the predictors(input data)and responses(output data)are multivariate functions(with d variables andd variables respectively),and the model coefficient lies in a reproducing kernel Hilbert space(RKHS).We show under mild condition on the reproducing kernel and input data statistics that the convergence rate of excess prediction risk by the regularized least squares is minimax *** examples based on medical image analysis and atmospheric point spread function estimation are considered and tested,and the results demonstrate that the performance of the proposed model is comparable with that of other testing methods.

关键词： Regularized least squares function-on-function regression non-asymptotic error bound reproducing kernel Hilbert space integral operator

Neural Network-based Adaptive State-feedback Control for High-order Stochastic Nonlinear Systems

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自动化学报 2014年第12期40卷 2968-2972页

作者： min Hui-fang DUAN Na School of Electrical Engineering & Automation Jiangsu Normal University

This paper focuses on investigating the issue of adaptive state-feedback control based on neural networks(NNs)for a class of high-order stochastic uncertain systems with unknown nonlinearities. By introducing the radial basis function neural network(RBFNN) approximation method, utilizing the backstepping method and choosing an approximate Lyapunov function, we construct an adaptive state-feedback controller which assures the closed-loop system to be mean square semi-global-uniformly ultimately bounded(M-SGUUB). A simulation example is shown to illustrate the effectiveness of the design scheme.

关键词：径向基函数神经网络状态反馈控制器随机非线性系统自适应高阶 Lyapunov函数非线性问题不确定系统

Multi-label local discriminative embedding

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Journal of Systems Engineering and Electronics 2017年第5期28卷 1009-1018页

作者： Jujie Zhang min fang Huimin Chai School of Computer Science and Technology Xidian University

Multi-label classification problems arise frequently in text categorization, and many other related applications. Like conventional categorization problems, multi-label categorization tasks suffer from the curse of high dimensionality. Existing multi-label dimensionality reduction methods mainly suffer from two limitations. First, latent nonlinear structures are not utilized in the input space. Second, the label information is not fully exploited. This paper proposes a new method, multi-label local discriminative embedding (MLDE), which exploits latent structures to minimize intraclass distances and maximize interclass distances on the basis of label correlations. The latent structures are extracted by constructing two sets of adjacency graphs to make use of nonlinear information. Non-symmetric label correlations, which are the case in real applications, are adopted. The problem is formulated into a global objective function and a linear mapping is achieved to solve out-of-sample problems. Empirical studies across 11 yahoo sub-tasks, Enron and Bibtex are conducted to validate the superiority of MLDE to state-of-art multi-label dimensionality reduction methods.

关键词： multi-label classification dimensionality reduction latent structure label correlation

Compressed sensing based channel estimation for fast fading OFDM systems

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Journal of Systems Engineering and Electronics 2010年第4期21卷 550-556页

作者： Xiaoping Zhou y.ng fang min Wang Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information Engineering Shanghai University Shanghai 200072 P. R. China Key Laboratory of Advanced Display and System Applications Shanghai 200072 P. R. China

A compressed sensing（CS） based channel estimation algorithm is proposed by using the delay-Doppler sparsity of the fast fading channel.A compressive basis expansion channel model with sparsity in both time and frequency domains is *** pilots in accordance with a novel random pilot matrix in both time and frequency domains are sent to measure the delay-Doppler sparsity *** relatively nonzero channel coefficients are tracked by random pilots at a sampling rate significantly below the Nyquist *** sparsity channels are estimated from a very limited number of channel measurements by the basis pursuit *** proposed algorithm can effectively improve the channel estimation performance when the number of pilot symbols is reduced with improvement of throughput efficiency.

关键词： compressed sensing sparse channel channel estimation fast fading.

Kernel Density Estimation Based Multiphase Fuzzy Region Competition Method for Texture Image Segmentation

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Communications in Computational Physics 2010年第8期8卷 623-641页

作者： fang Li Michael K.ng Department of Mathematics East China Normal UniversityShanghai 200241China Centre for Mathematical Imaging and Vision and Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong

In this paper,we propose a multiphase fuzzy region competition model for texture image *** the functional,each region is represented by a fuzzy membership function and a probability density function that is estimated by a nonparametric kernel density *** overall algorithm is very efficient as both the fuzzy membership function and the probability density function can be implemented *** apply the proposed method to synthetic and natural texture images,and synthetic aperture radar *** experimental results have shown that the proposed method is competitive with the other state-of-the-art segmentation methods.

关键词： Texture multiphase region competition kernel density estimation fuzzy membership function total variation

Microstructure and phase transformation of Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys

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Rare Metals 2024年第11期43卷 6048-6053页

作者： Cui-fang Dong Jing-min Wang Laboratory of Aerospace Materials and Performance(ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys were studied with the phase structure and magnetic *** martensitic transformation was observed over the whole composition *** martensitic transformation starting temperature(M_(s))increases from 256 K for x=15 to 350 K for x=18 and then decreases from 350 K for x=18 to333 K for x=20 by increasing substitution of Fe for *** austenitic Curie temperature((?))is observed for15≤x≤16 and 18≤x≤20,*** the martensitic Curie temperature(T^(A)_(X))is observed for x=*** 18ng in a relationship between martensite transformation temperature and Curie temperature as T^(A)_(C)

关键词： Ni-Fe-Ga Dual-phase Martensitic transformation Magnetic transition

Chinese Built-up Land in Floodplains Moving Closer to Freshwaters

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International Journal of Disaster Risk Science 2021年第3期12卷 355-366页

作者： y.ngqiang fang Shiqiang Du Jiahong Wen min Zhang Jiayi fang min Liu Key Laboratory of Geographic Information Science Ministry of EducationSchool of Geographic SciencesEast China Normal UniversityShanghai 200241China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China Institute for Environmental Studies Vrije Universiteit Amsterdam1081 HV AmsterdamNetherlands

Human proximity to water and its dynamics are important to understanding the socio-hydrological dilemma between using floodplains and avoiding flood ***,previous studies have not distinguished between the water proximity of built-up land in floodplains(BLF)and the water proximity of built-up land outside floodplains(BLOF).This article provides a new and spatiotemporal perspective of the BLF water proximities for understanding the changing flood risk in *** results show that China’s BLFs had an average water proximity of 5.41 km in *** of the BLFs(62%,25.889103 km2)were located within 3 km of *** 1990 to 2014,China’s BLFs increased rapidly by 81%from23.069103 km2 to 41.749103 km2,of which a large portion(57%)was concentrated in water surroundings(≤km),shortening the distance between BLFs and waterbodies by 169 *** BLF growth concentrated in water surroundings even in areas where BLFs have an overall increasing distance from *** the increases in the BLFs and their proximity to waterbodies can increase flood exposure and exacerbate flood *** scientific community and policymakers should pay attention not only to the volume of BLF growth,but also its spatial relationship with waterbodies.

关键词： China Floodplains Flood exposure Landscape sustainability Socio-hydrology Urbanization

Hybrid transmit antenna selection and maximal-ratio transmission systems

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Journal of Systems Engineering and Electronics 2007年第2期18卷 229-235页

作者： Zhu yaolin fang y.ng Wang min School of Communication and Information Engineering Shanghai Univ. Shanghai 200072P.R.China

Maximal-ratio transmission systems with transmit antenna selection is investigated. According to the order statistics of channel fiat fading coefficients, the closed-form expressions axe derived for average SNR with any amount of RF chains and average BER with two RF chains, respectively. The algorithm for calculating the minimum of total transmit antennas is presented in terms of reduced RF chains. The method of quantizing transmit precoders is employed in this study to decrease feedback information. Simulation results demonstrate the superiority of the proposed systems under full and quantized transmit precoders. The SNR of the proposed systems has been less degraded by the quantization of transmit precoder than that of pure maximal-ratio transmission systems.

关键词： Maximal-ratio transmission transmit antenna selection Lloyd quantization.

Collaborative multi-agent reinforcement learning based on experience propagation

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Journal of Systems Engineering and Electronics 2013年第4期24卷 683-689页

作者： min fang Frans C.A. Groen School of Computer Science and Technology Xidian University Informatics Institute University of Amsterdam

For multi-agent reinforcement learning in Markov games, knowledge extraction and sharing are key research problems. State list extracting means to calculate the optimal shared state path from state trajectories with cycles. A state list extracting algorithm checks cyclic state lists of a current state in the state trajectory, condensing the optimal action set of the current state. By reinforcing the optimal action selected, the action policy of cyclic states is optimized gradually. The state list extracting is repeatedly learned and used as the experience knowledge which is shared by teams. Agents speed up the rate of convergence by experience sharing. Competition games of preys and predators are used for the experiments. The results of experiments prove that the proposed algorithms overcome the lack of experience in the initial stage, speed up learning and improve the performance.

关键词： multi-agent Q learning state list extracting experience sharing.