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Chinese Journal of Chemistry 2013年第10期31卷 1250-1256页

作者： Yueqin Cai Gonghua song Xiao Chen School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & Pharmaceuticals East China University of Science and Technology Shanghai 200237 China

The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.

关键词： homogeneous catalysis acylation Heck reaction phosphine-free ligands

Regular Space-like Hypersurfaces in S1^m+1 with Parallel Para-Blaschke Tensors

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Acta Mathematica Sinica,English Series 2017年第10期33卷 1361-1381页

作者： Xing Xiao LI Hong Ru song School of Mathematics and Information Science He'nan Normal UniversityXinxiang 453007P.R.China

In this paper, we give a complete conformal classification of the regular space-like hyper- surfaces in the de Sitter Space S~＋1 with parallel para-Blaschke tensors.

关键词： Conformal form parallel para-Blaschke tensor conformal metric conformal second fun-damental form constant scalar curvature constant mean curvature

Lie Bialgebras of generalized Loop Virasoro Algebras

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Chinese Annals of Mathematics,Series B 2015年第3期36卷 437-446页

作者： Henan WU song WANG Xiaoqing YUE School of Mathematical Sciences Shanxi University Department of Mathematics Tongji University College of Information Technology Shanghai Ocean University

The first cohomology group of generalized loop Virasoro algebras with coefficients in the tensor product of its adjoint module is shown to be trivial. The result is used to prove that Lie bialgebra structures on generalized loop Virasoro algebras are coboundary triangular. The authors generalize the results to generalized map Virasoro algebras.

关键词： Lie bialgebra yang-Baxter equation generalized loop Virasoro algebra generalized map Viarasoro algebra

Robust control of exciting force for vibration control system with multi-exciters

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Science China(Technological Sciences) 2013年第10期56卷 2516-2524页

作者： song QiaoZhi yaNG ZhiChun WANG Wei Institute of Structural Dynamics and Control School of Aeronautics Northwestern Polytechnical University

Due to the dynamical character of electromagnetic exciter and the coupling between structure and exciter(s),the actual output force acting on the structure is usually not equal to the exact value that is supposed to be,especially when multi-exciters are used as actuators to precisely actuate large flexible *** is necessary to consider these effects to ensure the force generated by each exciter is the same as *** this paper,a robust control method is proposed for the multi-input and multi-output(MIMO)structural vibration control system to trace the target actuating force of each exciter.A special signal is designed and put into the coupled mul-ti-exciter-structure system,and the input and output signals of the system are used to build a dynamic model involving both the dynamical characters of the exciters and the structure using the subspace identification *** the uncertainty factors of the multi-exciter/structure system,an H-infinity robust controller is designed to decouple the coupling between structure and exciters based on the identified system model.A MIMO vibration control system combined with a flexible plate and three electromagnetic exciters is adopted to demonstrate the proposed method,both numerical simulation and model experiments showing that the output force of each exciter can trace its target force accurately within the requested frequency band.

关键词： multi-exciters system exciting force control subspace identification robust control experiment modeling

ROLLING BEARING FAULT DETECTION USING CORRELATION TECHNIQUE

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Applied Mathematics and Mechanics(English Edition) 1992年第7期13卷 617-622页

作者： Xu Yin-ge yan Yu-ling Peking Administrative Personnel College of Communications Beijing Keio University Japan

It's known that auto-correlation technique is effective in extracting periodical signals from random *** the case of fault monitoring of rolling element bearing,we can't acquire the fault information directly from the original signal because of the difference of signal *** the signal is shown as the wide band random signal in auto-correlation *** this paper,the signal is pre-processed and the results are proved ***,by taking the auto-correlation function we can obtain the determined and comparable *** is very important for establishing the data base of running condition and for detecting the faults.

关键词： auto-correlation function wave shape factor crest factor impulse factor kurtosis factor

Feasibility Analysis of Crane Automation

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International Journal of Plant Engineering and Management 2006年第1期11卷 30-39页

作者： DONG Ming-xiao MEI Xue-song JIANG ge-dong ZHANG Gui-qing School of Mechanical Engineering Xi＇an Jiaotong University Xi＇an 710049 P. R. China Shandong institute of Architecture and Engineering Jinan 250014 P. R. China

This paper summarizes the modeling methods, open-loop control and closed-loop control techniques of various forms of cranes, worldwide, and discusses their feasibilities and limitations in engineering. Then the dynamic behaviors of cranes are analyzed. Finally, we propose applied modeling methods and feasible control techniques and demonstrate the feasibilities of crane automation.

关键词： crane automation dynamics control modeling

Absolute stabilization of singular systems with ferromagnetic hysteresis nonlinearity

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Science China(Information Sciences) 2013年第7期56卷 259-272页

作者： ZHANG HuaGuang WANG YingChun song Zheng School of Information Science and Engineering Northeastern University Stake Key Laboratory of Synthetical Automation of Process Industies (Northeasten University) Beijing Institute of Spacecraft System Engineering

This paper is concerned with the absolute stabilization problem of a class of singular systems with feedback connected ferromagnetic hysteresis nonlinearities. Firstly, a novel differential-integral loop transformation framework is developed to achieve an augmented singular system model. Secondly, by constructing a new passive output derivative operator of hysteresis nonlinearity and establishing the bound condition of the solution of ferromagnetic hysteresis model, the equivalent absolute stability criterion of singular systems with hysteresis feedback is derived based on KYP method and LMIs technique. Furthermore, the strict LMIs conditions for absolute stabilization are obtained, which can easily be checked by the LMI toolbox in MATLAB. Finally, two examples are given to illustrate the effectiveness of the proposed method.

关键词： ferromagnetic hysteresis singular systems absolute stability extended Popov criterion

Empirical Likelihood Based Goodness-of-fit Testing for generalized Linear Mixed Models

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 37-48页

作者： song-qiao WEN Li-xing ZHU College of Mathematics and Computational Science Shenzhen University School of Statistics Renmin University of China

In this paper, we propose a bias-corrected empirical likelihood （BCEL） ratio to construct a goodness- of-fit test for generalized linear mixed models. BCEL test maintains the advantage of empirical likelihood that is self scale invariant and then does not involve estimating limiting variance of the test statistic to avoid deteri- orating power of test. Furthermore, the bias correction makes the limit to be a process in which every variable is standard chi-squared. This simple structure of the process enables us to construct a Monte Carlo test proce- dure to approximate the null distribution. Thus, it overcomes a problem we encounter when classical empirical likelihood test is used, as it is asymptotically a functional of Gaussian process plus a normal shift function. The complicated covariance function makes it difficult to employ any approximation for the null distribution. The test is omnibus and power study shows that the test can detect local alternatives approaching the null at parametric rate. Simulations are carried out for illustration and for a comparison with existing method.

关键词： Empirical likelihood bias correction monte carlo test generalized linear mixed model

Tightly Secure Public-Key Cryptographic Schemes from One-More Assumptions

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Journal of Computer Science & Technology 2019年第6期34卷 1366-1379页

作者： ge Wu Jian-Chang Lai Fu-Chun Guo Willy Susilo Fu-Tai Zhang School of Cyber Science and Engineering Southeast UniversityNanjing 211189China Institute of Cybersecurity and Cryptology School of Computing and Information Technology University of WollongongWollongong 2522Australia Purple Mountain Laboratories Nanjing 211111China School of Mathematics and Computer Science Fujian Normal UniversityFuzhou 350117China School of Computer Science and Technology Nanjing Normal UniversityNanjing 210023China

A tightly secure cryptographic scheme refers to a construction with a tight security reduction to a hardness assumption,where the reduction loss is a small constant.A scheme with tight security is preferred in practice since it could be implemented using a smaller parameter to improve ***,Bader et al.(EUROCRYPT 2016)have proposed a comprehensive study on the impossible tight security reductions for certain(e.g.,key-unique)public-key cryptographic schemes in the multi-user with adaptive corruptions(MU-C)setting built upon non-interactive *** assumptions of one-more version,such as one-more computational Diffie-Hellman(n-CDH),are variants of the standard assumptions and have found various ***,whether it is possible to have tightly secure key-unique schemes from the one-more assumptions or the impossible tight reduction results also hold for these assumptions remains *** this paper,we give affirmative answers to the above question,i.e.,we can have efficient key-unique public-key cryptographic schemes with tight security built upon the one-more ***,we propose a digital signature scheme and an encryption scheme,both of which are key-unique and have tight MU-C security under the one-more computational Diffie-Hellman(n-CDH)*** results also reflect from another aspect that there indeed exists a gap between the standard assumptions and their one-more version counterparts.

关键词： public-key cryptography multi-user setting tight security one-more assumption

A Novel Edge Computing Based Area Navigation Scheme

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Computers, Materials & Continua 2020年第12期65卷 2385-2396页

作者： Jianzhong Qi Qingping song Jim Feng School of Information Science and Technology North China University of TechnologyBeijing100144China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Science and Technology on Information Systems Engineering Laboratory Beijing Institute of Control and Electronic TechnologyBeijing100038China Amphenol Global Interconnect Systems San JoseCA 95131USA

The area navigation system,discussed in this paper,is composed of ground responders and a navigation terminal and can position a high-velocity aircraft and measure its *** navigation system is silent at ordinary *** sends out a request signal when positioning is required for an aircraft,and then the ground responders send a signal for resolving the *** the direct sequence spread spectrum and frequency hopping,the concealed communication mode is used in the whole communication process,with short communication pulses as much as possible,so the system has strong concealment and anti-interference *** the transmission delay is apparent in the response communication mode,there is a big error where the common navigation algorithm is used for the positioning and velocity measurement of a high-velocity *** this paper,a new algorithm is proposed,which can eliminate the influence of response communication delay on the positioning of a high-velocity moving target to realize the precise positioning and velocity measurement of a high-velocity aircraft.

关键词： Navigation pseudo-noise code ranging positioning velocity measurement edge computing