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Improved scheme to accelerate support vector regression

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1086-1090页

作者： Zhao Yongping sun jianguo Dept. of Energy and Power Engineering Nanjing Univ. of Aeronautics and Astronautics Nanjing 210016 P. R. China

The computational cost of support vector regression in the training phase is O （N^3）, which is very expensive for a large scale problem. In addition, the solution of support vector regression is of parsimoniousness, which has relation to a part of the whole training data set. Hence, it is reasonable to reduce the training data set. Aiming at the scheme based on k-nearest neighbors to reduce the training data set with the computational complexity O （kMN^2）, an improved scheme is proposed to accelerate the reducing phase, which cuts down the computational complexity from O （kMN^2） to O （MN^2）. Finally, experimental results on benchmark data sets validate the effectiveness of the improved scheme.

关键词： support vector regression parsimoniousness k-nearest neighbors computational complexity.

Regression Analysis of Interval-Censored Data with Informative Observation Times Under the Accelerated Failure Time Model

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Journal of Systems Science & Complexity 2022年第4期35卷 1520-1534页

作者： ZHAO Shishun DONG Lijian sun jianguo Center for Applied Statistical Research School of MathematicsJilin UniversityChangchun130012China Department of Statistics University of MissouriColumbiaMO65211USA

This paper discusses regression analysis of interval-censored failure time data arising from the accelerated failure time model in the presence of informative *** the problem,a sieve maximum likelihood estimation approach is proposed and in the method,the copula model is employed to describe the relationship between the failure time of interest and the censoring or observation *** I-spline functions are used to approximate the unknown functions in the model,and a simulation study is carried out to assess the finite sample performance of the proposed approach and suggests that it works well in practical *** addition,an illustrative example is provided.

关键词： Accelerated failure time model copula models informative censoring interval-censored data splines

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Leaching of aluminum from coal spoil by mechanothermal activation

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Frontiers of Chemical Science and Engineering 2015年第2期9卷 216-223页

作者： Xiaoxue sun Yuzhu sun jianguo YU State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

The process of order to recover aluminum investigated. The CS was activating coal spoil （CS） in as a high value product was first characterized by X-ray fluorescence （XRF）, X-ray diffraction （XRD） and thermo- gravimetric analysis-differential scanning calorimetry （TGA-DSC） in order to determine the chemical and mineral compositions of the CS. Then a mechanothermal activation method was adopted to increase the aluminum activity in the coal spoil. Over 95% of the aluminum in the CS could be extracted using this activation method. The mechanothermal activation process promoted the destruc- tion of kaolinite structures and hindered the formation of amorphous γ-Al2O3. This resulted in a high aluminum leaching activity in the mechanothermally activated CS.

关键词： coal spoil mechanothermal compound activa-tion leaching

Special control system of satellite-gesture simulation

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Journal of Systems Engineering and Electronics 2005年第4期16卷 862-865页

作者： Han jianguo sun Yongwen sun Caihong School of Information Science and Technology Beijing Univ. of Chemical Technology Beijing 100029 P. R. China

To implement a simulation of fir-floating-platform with higher frequency vibration, A satdlite-gesture emulation system with the functions of selectable high-frequency vibration-simulation and high-accuracy stability （with the control resolution within ± 5 × 10^-4 angle-degrees）, controlled by using filtered-feedback and fuzzy-preeminence technology is designed and structured. The system is based on the analysis of dynamic and static composed-force-moment and disturhance factors. Through computational simulation, laboratory experiments and field-demo, it is proved that the system operation is available, practical, and propitious for minifying drive-power. These system structures and control strategies can be widely used in the fields such as astronomy, space navigation, deep-sea operation, high altitude motion, and weightless experiment, where a floating body must be controlled or simulated.

关键词： satellite gesture dimulation forced vibration fuzzy-vorecast feedback filtering vibration center-point control.

A Simulation-Extrapolation Approach to the Analysis of Interval-Censored Failure Time Data with Mis-Measured Covariates

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Journal of Systems Science & Complexity 2024年第6期37卷 2721-2737页

作者： FENG Fan ZHAO Shishun LI Shuwei sun jianguo School of Economics and Statistics Guangzhou UniversityGuangzhou 510006China School of Mathematics Jilin UniversityChangchun 130021China Department of Statistics University of MissouriMO 6521lUSA

Interval-censored failure time data arise frequently in periodical follow-up studies including clinical trials and epidemiological *** addition,some covariates may be subject to measurement errors due to the instrumental contamination,biological variation or other *** the analysis of interval-censored data with mis-measured covariates,the existing methods either assume a parametric model or rely on the availability of replicated surrogate measurements for the error-prone covariate,which both have obvious *** overcome these shortcomings,the authors propose a simulation-extrapolation estimation procedure under a general class of transformation *** resulting estimators are shown to be consistent and asymptotically *** numerical results obtained from a simulation study indicate that the proposed method performs reasonably well in *** particular,the proposed method can reduce the estimation bias given by the naive method that does not take measurement errors into ***,the proposed method is applied to a real data set on hypobaric decompression sickness.

关键词： Interval censoring measurement error regression analysis semiparametric model SIMEX

Regression Analysis of Misclassified Current Status Data with Informative Observation Times

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Journal of Systems Science & Complexity 2023年第3期36卷 1250-1264页

作者： WANG Wenshan XU Da ZHAO Shishun sun jianguo Center for Applied Statistical Research School of MathematicsJilin UniversityChangchun 130012China Key Laboratory of Applied Statistics of MOE and School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China Department of Statistics University of MissouriColumbiaMO 65211USA

Misclassified current status data arises if each study subject can only be observed once and the observation status is determined by a diagnostic test with imperfect sensitivity and *** the situation,another issue that may occur is that the observation time may be correlated with the interested failure time,which is often referred to as informative censoring or observation *** is well-known that in the presence of informative censoring,the analysis that ignores it could yield biased or even misleading *** this paper,the authors consider such data and propose a frailty-based inference *** particular,an EM algorithm based on Poisson latent variables is developed and the asymptotic properties of the resulting estimators are *** numerical results show that the proposed method works well in practice and an application to a set of real data is provided.

关键词： Current status data EM algorithm informative censoring misclassification proportional hazard model

The influence of irregular seafloor topography on the seismic wave field and migration imaging

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Acta Oceanologica Sinica 2019年第3期38卷 151-158页

作者： Fuxing Han Kun Wang jianguo sun College for Geoexploration Science Technology Jilin University Jilin Communications Polytechnic

One of the problems experienced in marine geophysical exploration is that the layered features in the migration imaging profile are blurred and the seismic energy reflected is weaker in the middle or lower parts. In this study we model the seismic wavefield records in the undulating seafloor when there is both a slight change and significant change in seafloor topography to analyze its influence on the seismic reflection data and migration imaging profiles. We compare and analyze the wave field records collected at the same point on the original and modified velocity models, and the cross-bonding resulting migration imaging profiles. The results show that whether the seismic reflection data collection is performed along the direction of the survey line or against the direction of the survey line, slight changes in the seafloor topography have little effect on the wave field records and the migration profile, while significant changes in the seafloor topography have great effect on both the wave field records and migration profile.

关键词： seafloor topography seismic wave field seismic reflections migration imaging

Wavelet neural network based watermarking technology of 2D vector maps

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High Technology Letters 2011年第3期17卷 259-262页

作者： sun jianguo Men Chaoguang School of Computer Science and Technology Harbin Engineering University Harbin 150001 P. R. China

A novel lossless information hiding algorithm based on wavelet neural network for digital vector maps is introduced. Wavelet coefficients being manipulated are embedded into a vector map, which could be restored by adjusting the weights of neurons in the designed neural network. When extracting the watermark extraction, those coefficients would be extracted by wavelet decomposition. With the trained multilayer feed forward neural network, the watermark would be obtained finally by measuring the weights of neurons. Experimental results show that the average error coding rate is only 6% for the proposed scheme and compared with other classical algorithms on the same tests, it is indicated that the proposed algorithm hashigher robustness, better invisibility and less loss on precision.

关键词： information hiding digital watermarking vector map neural network

An integrated approach to improve the performance of lean–electrolyte lithium–sulfur batteries

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Journal of Energy Chemistry 2022年第4期31卷 585-592页

作者： Hualin Ye jianguo sun Yun Zhao Jim Yang Lee Department of Chemical and Biomolecular Engineering National University of Singapore119260Singapore Department of Mechanical Engineering National University of Singapore117575Singapore

While the sulfur conversion reaction kinetics in Li–S batteries is nowadays improved by the use of appropriate electrocatalysts,it remains a challenge for the batteries to perform well under the lean electrolyte condition where polysulfide shuttle,electrode passivation and the loss of electrolyte due to side reactions,are *** challenges are addressed in this study by the tandem use of a polysulfide conversion catalyst and a redox–targeting mediator in a gel sulfur ***,the gel cathode reduces the polysulfide mobility and hence the polysulfide shuttle and the passivation of the lithium anode by the crossover *** redox mediator restrains the deposition of inactive sulfur species in the cathode thereby enabling the Fe–N and Co–N co–doped carbon catalyst to prolong its catalytic ***,the integrated catalytic system is able to increase the discharge capacity of high–loading (6.8 mg cm^(-2)) lean–electrolyte (4.0μL mg^(-1)) Li–S batteries from~630 to~1316 m Ah g^(-1),concurrently with an improvement of the cycle life (600 cycles with 46%capacity retention at 1.0 m A cm^(-2)).Redox mediator assisted catalysis in a gel cathode is therefore an effective strategy to extend the application of the sulfur conversion catalyst in lean electrolyte Li–S batteries.

关键词： Redox mediators Gel electrolytes Polysulfide catalysis Lean electrolyte Lithium–sulfur batteries