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A Hybrid BPNN-GARF-SVR Prediction Model Based on EEMD for Ship Motion

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Computer Modeling in Engineering & Sciences 2023年第2期134卷 1353-1370页

作者： hao han Wei Wang School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing100191China

Accurate prediction of shipmotion is very important for ensuringmarine safety,weapon control,and aircraft carrier landing,*** motion is a complex time-varying nonlinear process which is affected by many *** series analysis method and many machine learning methods such as neural networks,support vector machines regression(SVR)have been widely used in ship motion ***,these single models have certain limitations,so this paper adopts amulti-model prediction ***,ensemble empirical mode decomposition(EEMD)is used to remove noise in ship motion *** the randomforest(RF)prediction model optimized by genetic algorithm(GA),back propagation neural network(BPNN)prediction model and SVR prediction model are respectively established,and the final prediction results are obtained by results of three *** the weights coefficients are determined by the correlation coefficients,reducing the risk of prediction and improving the *** experimental results show that the proposed combined model EEMD-GARF-BPNN-SVR is superior to the single predictive model and more *** mean absolute percentage error(MAPE)of the proposed model is 0.84%,but the results of the single models are greater than 1%.

关键词： Back propagation neural network ensemble empirical mode decomposition genetic algorithm random forest SVR ship motion prediction

Travelling Wave Solutions of Integro-differential Equations of One-dimensional Neuronal Networks

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Acta Mathematicae Applicatae Sinica 2015年第3期31卷 767-782页

作者： han hao Rémi VAILLANCOURT Department of Mathematics and Statistics University of Ottawa

Travelling wave solutions of integro-differential equations for modeling one-dimensional neuronal networks, are studied. Under moderate continuity assumptions, necessary and sufficient conditions for the existence and uniqueness of monotone increasing（decreasing） Travelling wave solutions are established. Some faults in previous studies are corrected.

关键词： travelling wave solution neuronal network integral-differential equation

Magnetometer-only linear attitude estimation for bias momentum pico-satellite

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 455-464页

作者： Ke han hao WANG Zhong-he JIN Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Satellite attitude information is essential for pico-satellite applications requiring light-weight,low-power,and fast-computation *** objective of this study is to provide a magnetometer-only attitude estimation method for a low-altitude Earth orbit,bias momentum *** on two assumptions,the spacecraft spherical symmetry and damping of body rates,a linear kinematics model of a bias momentum satellite's pitch axis is derived,and the linear estimation algorithm is *** algorithm combines the linear Kalman filter(KF) with the classic three-axis attitude determination method(TRIAD).KF is used to estimate satellite's pitch axis orientation,while TRIAD is used to obtain information concerning the satellite's three-axis *** tests confirmed that the algorithm is suited to the time-varying model errors resulting from both *** estimate result keeps tracking satellite attitude motion during all damping,stable,and free rotating control *** with nonlinear algorithms,such as extended Kalman filer(EKF) and square root unscented Kalman filer(SRUKF),the algorithm presented here has an almost equal performance in terms of convergence time and estimation accuracy,while the consumption of computing resources is much lower.

关键词： Pico-satellite Attitude estimation Bias momentum Magnetometer Kalman filter(KF)

Pico-satellite Autonomous Navigation with Magnetometer and Sun Sensor Data

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Chinese Journal of Aeronautics 2011年第1期24卷 46-54页

作者： han Ke WANG hao TU Binjie JIN Zhonghe Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

This article presents a near-Earth satellite orbit estimation method for pico-satellite applications with light-weight and low-power requirements. The method provides orbit information autonomously from magnetometer and sun sensor, with an extended Kalman filter （EKF）. Real-time position/velocity parameters are estimated with attitude independently from two quantities： the measured magnitude of the Earth’s magnetic field, and the measured dot product of the magnetic field vector and the sun vector. To guarantee the filter’s effectiveness, it is recommended that the sun sensor should at least have the same level of accuracy as magnetometer. Furthermore, to reduce filter’s computation expense, simplification methods in EKF’s Jacobian calculations are introduced and testified, and a polynomial model for fast magnetic field calculation is developed. With these methods, 50% of the computation expense in dynamic model propagation and 80% of the computation burden in measurement model calculation can be reduced. Tested with simulation data and compared with original magnetometer-only methods, filter achieves faster convergence and higher accuracy by 75% and 30% respectively, and the suggested simplification methods are proved to be harmless to filter’s estimation performance.

关键词： pico-satellite autonomous navigation orbit estimation magnetometer Kalman filter

Applying genetic algorithms to the study of protein mutation theory

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Chinese Science Bulletin 1998年第23期43卷 1977-1982页

作者： Zhirong Sun hao han Wang Tsing Hua Univ Dept Biol Sci & Biotechnol Beijing 100084 Peoples R China

Genetic algorithms were applied to the study of simulation of protein mutation carried out on two_dimensional lattice model; to the study of effects of single mutation and double mutation on protein folding and protein structure stability. It is found that in two_dimensional lattice models, replacement of inner core hydrophobic residue by hydrophilic residue will result in reduction of protein stability; at the same time the number of residues of protein surface relatively grows with increase of protein chain length; and most mutations occur in residues of protein surface, these mutations are all neutral and have no effects on protein natural structure. The two mutations of double mutation are interactive and related to each other.

关键词： genetic algorithm two_dimensional lattice model single mutation double mutation.

Soil erosion differences in paired grassland and forestland catchments on the Chinese Loess Plateau

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Journal of Mountain Science 2023年第5期20卷 1336-1348页

作者： YANG Si-qi LUO Da han hao JIN Zhao Interdisciplinary Research Center of Earth Science Frontier State Key Laboratory of Earth Surface Processes and Resource EcologyBeijing Normal UniversityBeijing 100875China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China College of Geology Engineering and Geomatics Chang'an UniversityXi'an 710054China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China

In this study,two adjacent gauged catchments on the Chinese Loess Plateau were selected,in which one catchment was afforested and one was restored with natural vegetation in *** distributions of soil erosion rates were estimated between 2010 and 2020 with a high spatial resolution of 2 m in the paired catchments based on the Revised Universal Soil Loss Equation model(RUSLE)and Geographic Information Systems(GIS).The results showed that the simulated soil erosion rates in 2010-2020 averaged 12.58 and 8.56 t ha^(-1)a^(-1)for the grassland and forestland catchment,***,areas with high soil erosion rates(>80t ha^(-1)a^(-1))were mainly distributed in the topography with steep slope gradients(>45°).Comparisons between simulated soil erosion rates and observed annual sediment loads indicated that the simulation results of the grassland catchment were lower than the observed values,while it was reversed in the forestland *** conclude that the RUSLE model cannot simulate the gravity erosion induced by extreme rainfall *** the forestland catchment,insufficient streamflow and dense vegetation coverage are crucial factors resulting in hindering the movement of sediments.

关键词： Catchment comparison Soil erosion RUSLE model Vegetation effect Topography effect Spatial analysis

Vehicle survival patterns in China

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Science China(Technological Sciences) 2011年第3期54卷 625-629页

作者： hao han WANG HeWu OUYANG MingGao CHENG Fei State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China China Automotive Energy Research Center (CAERC) Tsinghua University Beijing 100084 China

The vehicle survival pattern describes the process that the survival ratio of vehicles decreases with the growth of vehicle age. Vehicle average life span and vehicle scrappage intensity are the key features of vehicle survival patterns and are important for the projection of China's vehicle scrappage and ownership. In this study, we modeled the vehicle survival patterns of nine classifications of vehicles in China by employing the Weibull distribution, and obtained the vehicle survival ratio functions. It is estimated that the average life spans of private passenger vehicles, government and business vehicles, non-operating buses, heavy duty, medium duty and light duty trucks are 14.5, 13.1, 11.5, 12.8, 10.1, and 8 years, respectively. The scrappage intensities of these vehicles are similar. Average life spans of taxis, transit buses and non-transit operating buses are 5, 9, and 5.5 years with the pattern of mandatory scrappage. Vehicle scrappages in China are mainly regulated by the upper limits of vehicle distances traveled specified by the compulsory scrappage standards.

关键词： vehicle survival pattern average life span scrappage intensity

A Stochastic Filtering Algorithm Using Schr¨odinger Equation

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自动化学报 2014年第10期40卷 2370-2376页

作者： WU hao-han JIN Fu-Jiang LAI Lian-You WANG Liang College of Information Science and Engineering Huaqiao Universityxiamen 361021China College of Mechanical Engineeringand Automation Huaqiao University Xiamen 361021 China

This paper provides a new adaptive algorithm for single-step prediction by modeling the potential field of a one dimension Schrodinger wave equation using neural *** new architecture is referred to as the recurrent quantum neural network (RQNN).The RQNN can filter the signal embedded with non-stationary noise without any priori knowledge of the shape of the signal and statistical properties of the *** compared the simulation results of the RQNN with a classical adaptive stochastic *** is shown that the RQNN is much more efficient in denoising signals embedded with Gaussian stationary,non-Gaussian stationary and Gaussian nonstationary noise such as DC,sinusoid,staircase and speech *** RQNN can enhance the signal to noise rate (SNR) by 20 dB,which is more than 10 dB given by the traditional technology when it denoising sinusoid signal.

关键词：波动方程滤波算法随机模拟神经网络自适应算法非平稳噪声语音信号量子神经网络

Cable-like Au@SiO2 Janus composite nanorods

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Chinese Chemical Letters 2018年第3期29卷 353-356页

作者： Tian-hao han Fu-Xin Liang Zhen-Zhong Yang State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

Cable-like Au@SiO2 Janus composite nanorods with PS and PEG grafting on both ends respectively are fabricated by skiving in combination of a post favorable modification. The cable-like Au@SiO2 composite nanofibers are synthesized in the channel of porous anodic aluminium oxide （AAO） membrane. After skiving, the corresponding composite nanorods are obtained. Following, PEG-SH and PS-SH are conjugated onto the two ends of the nanorods by a selective partial modification, respectively. Length and diameter of the Au@SiO2 Janus composite nanorods can be tuned controllably. It can be extended to fabricate a variety of different Janus nanorods with different compositions and microstructures.

关键词： AAO membrane Janus Nanomds Skiving Selective modification