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Intelligent Diagnosis of Short Hydraulic Signal Based on Improved EEMD and SVM with Few Low-dimensional Training Samples

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 396-405页

作者： zhang Meijun TANG Jian zhang xiaoming zhang Jiaojiao Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing 210007 China Nanjing University of Aeronautics and Astronautics Nanjing 210007 China

The high accurate classification ability of an intelligent diagnosis method often needs a large amount of training samples with high-dimensional eigenvectors, however the characteristics of the signal need to be extracted accurately. Although the existing EMD（empirical mode decomposition） and EEMD（ensemble empirical mode decomposition） are suitable for processing non-stationary and non-linear signals, but when a short signal, such as a hydraulic impact signal, is concerned, their decomposition accuracy become very poor. An improve EEMD is proposed specifically for short hydraulic impact signals. The improvements of this new EEMD are mainly reflected in four aspects, including self-adaptive de-noising based on EEMD, signal extension based on SVM（support vector machine）, extreme center fitting based on cubic spline interpolation, and pseudo component exclusion based on cross-correlation analysis. After the energy eigenvector is extracted from the result of the improved EEMD, the fault pattern recognition based on SVM with small amount of low-dimensional training samples is studied. At last, the diagnosis ability of improved EEMD＋SVM method is compared with the EEMD＋SVM and EMD＋SVM methods, and its diagnosis accuracy is distinctly higher than the other two methods no matter the dimension of the eigenvectors are low or high. The improved EEMD is very propitious for the decomposition of short signal, such as hydraulic impact signal, and its combination with SVM has high ability for the diagnosis of hydraulic impact faults.

关键词： hydraulic impact fault improved EEMD end effect overshoot-undershoot SVM intelligent fault diagnosis short signal

Dembowski-Ostrom Polynomials from Reversed Dickson Polynomials

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Journal of Systems Science & Complexity 2016年第1期29卷 259-271页

作者： zhang xiaoming WU Baofeng LIU Zhuojun Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of Sciences Beijing 100190 China State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences Beijing 100093 China

This paper gives a full classification of Dembowski-Ostrom polynomials derived from the compositions of reversed Dickson polynomials and monomials over finite fields of characteristic *** authors also classify almost perfect nonlinear functions among all such Dembowski-Ostrom polynomials based on a general result describing when the composition of an arbitrary linearized polynomial and a monomial of the form x^(2+2^α) is almost perfect *** turns out that almost perfect nonlinear functions derived from reversed Dickson polynomials are all extended affine equivalent to the well-known Gold functions.

关键词： Almost perfect nonlinear function Dembowski-Ostrom polynomial linearized polynomial reversed Dickson polynomial

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东亚共同体建设：历史模式与秩序观念

世界经济与政治论坛 2011年第1期 37-47页

作者：张小明北京市海淀区颐和园路5号 100871

在东亚的历史上曾经出现过不同的地区共同体建设模式,其中包含着不同的地区秩序观念。东亚共同体建设,就是如何把东亚塑造成一个地区和建立某种地区秩序的过程,或者说,就是怎么样实现东亚政治、经济、文化的一体化。东亚共同体之成为现... 详细信息

在东亚的历史上曾经出现过不同的地区共同体建设模式,其中包含着不同的地区秩序观念。东亚共同体建设,就是如何把东亚塑造成一个地区和建立某种地区秩序的过程,或者说,就是怎么样实现东亚政治、经济、文化的一体化。东亚共同体之成为现实,需要满足三个基本条件:一系列国家组成一个地理区域、一系列共有的行为规范和制度、共有的地区意识或地区认同。有史以来,东亚地区先后出现过几种不同的模式或秩序,即以中国为中心的东亚"朝贡体系"、以日本为中心的"大东亚共荣圈"以及当代的东亚共同体模式。这些模式具有完全不同的历史背景和具体特征:第一个模式是稳定的,但却是不平等的;第二个模式是征服性的,也是不平等的,并且导致了大规模的武力冲突;第三个模式有着很大的不确定性。当前和未来的东亚共同体建设,必须回答和解决以下几个重要问题:未来的东亚共同体是开放的还是封闭的?是由大国主导的还是成员国完全平等的?东亚地区共同体的共有观念、规则和制度如何形成?因此,东亚国家需要吸取历史经验和教训,在实践中探索符合本地区特点和利益的地区共同体建设模式。

关键词：东亚地区共同体历史模式秩序观念

Optimizing the Gabor Bandwidth of satellite navigation signals by MCS signal expression

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1077-1082页

作者： zhang xiaoming YAO Zheng LU MingQuan Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing Global Information Center Beijing 100094China

Satellite navigation is playing an important role in social *** performances of the services a navigation system provides are the concern of the builders and *** signal structure determines the inherent ability of a satellite navigation system to provide these ***,it is necessary and reasonable to optimize the signal in the initial *** waveforms of signals in satellite navigation chips are an important aspect of the signal's structure,which impact the characteristics of the autocorrelation function and power spectrum in the time domain and frequency *** range accuracy of a navigation system is usually described by its Gabor *** Gabor Bandwidth of the Binary Offset Carrier (BOC) modulation in next-generation GNSS signal systems is not *** paper presents a signal expression based on Multilevel Coded Symbol (MCS) signals,which can describe the fine structure of navigation *** this expression,we can optimize the Gabor Bandwidth of the signal,and find out the corresponding MCS vector and chip waveform,so as to get higher range *** method in this paper,in theory,is of great value in the design of next-generation navigation signals.

关键词： satellite navigation MCS signal Gabor Bandwidth bound

The function of small RNAs in plant biotic stress response

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Journal of Integrative Plant Biology 2016年第4期58卷 312-327页

作者： Juan Huang Meiling Yang xiaoming zhang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences

Small RNAs（s RNAs） play essential roles in plants upon biotic stress. Plants utilize RNA silencing machinery to facilitate pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity to defend against pathogen attack or to facilitate defense against insect herbivores. Pathogens, on the other hand, are also able to generate effectors and s RNAs to counter the host immune response. The arms race between plants and pathogens/insect herbivores has triggered the evolution of s RNAs,RNA silencing machinery and pathogen effectors. A great number of studies have been performed to investigate the roles of s RNAs in plant defense, bringing in the opportunity to utilize s RNAs in plant protection. Transgenic plants with pathogen-derived resistance ability or transgenerational defense have been generated, which show promising potential as solutions for pathogen/insect herbivore problems in the field. Here we summarize the recent progress on the function of s RNAs in response to biotic stress, mainly in plant-pathogen/insect herbivore interaction,and the application of s RNAs in disease and insect herbivore control.

关键词： Small RNA plant immunity transgenerational defense pathogen-derived resistance

Numerical Robust Stability Estimation in Milling Process

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 953-959页

作者： zhang xiaoming ZHU Limin DING Han XIONG Youlun State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China

The conventional prediction of milling stability has been extensively studied based on the assumptions that the milling process dynamics is time invariant. However, nominal cutting parameters cannot guarantee the stability of milling process at the shop floor level since there exists many uncertain factors in a practical manufacturing environment. This paper proposes a novel numerical method to estimate the upper and lower bounds of Lobe diagram, which is used to predict the milling stability in a robust way by taking into account the uncertain parameters of milling system. Time finite element method, a milling stability theory is adopted as the conventional deterministic model. The uncertain dynamics parameters are dealt with by the non-probabilistic model in which the parameters with uncertainties are assumed to be bounded and there is no need for probabilistic distribution densities functions. By doing so, interval instead of deterministic stability Lobe is obtained, which guarantees the stability of milling process in an uncertain milling environment, In the simulations, the upper and lower bounds of Lobe diagram obtained by the changes of modal parameters of spindle-tool system and cutting coefficients are given, respectively. The simulation results show that the proposed method is effective and can obtain satisfying bounds of Lobe diagrams. The proposed method is helpful for researchers at shop floor to making decision on machining parameters selection.

关键词： robust stability estimation sensitivity analysis interval arithmetic decision making

A Combinatorial Condition and Boolean Functions with Optimal Algebraic Immunity

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Journal of Systems Science & Complexity 2015年第3期28卷 725-742页

作者： JIN Qingfang LIU Zhuojun WU Baofeng zhang xiaoming Key Laboratory of System and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences

This paper first proposes an infinite class of 2k-variable Boolean functions with high nonlinearity and high algebraic degree. Then an infinite class of balanced Boolean functions are proposed by modifying the above Boolean functions. This class of balanced Boolean functions have optimal algebraic degree and high nonlinearity. Both classes have optimal algebraic immunity based on a general combinatorial conjecture.

关键词： Algebraic degree algebraic immunity balancedness Bent function Boolean function nonlinearity.

Decoding the complexity of metastasis

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Cancer Biology & Medicine 2022年第3期19卷 284-288页

作者： Yingcheng Wu Tiancheng zhang xiaoming zhang Qiang Gao Department of Liver Surgery and Transplantation Key Laboratory of Carcinogenesis and Cancer Invasion(Ministry of Education)Liver Cancer InstituteZhongshan HospitalFudan UniversityShanghai 200032China The Center for Microbes Development and HealthKey Laboratory of Molecular Virology and ImmunologyInstitute Pasteur of ShanghaiChinese Academy of SciencesShanghai 200031China Key Laboratory of Medical Epigenetics and Metabolism Institutes of Biomedical SciencesFudan UniversityShanghai 200032China State Key Laboratory of Genetic Engineering Fudan UniversityShanghai 200433China

Cancer metastasis remains one of the most confounding questions in oncology1,*** current cutting-edge techniques enable very early detection of tumors,profiling whether a tumor has already begun to spread and where it has attempted to colonize remains a major ***,metastatic seeding events exhibit remarkable temporal and spatial heterogeneity,wherein the origin(primary site)and destination(metastatic site)are highly *** example,liver metastasis is particularly common and remains a leading cause of mortality3.

关键词： metastasis mortality founding

A NOTE ON TWO CLASSES OF BOOLEAN FUNCTIONS WITH OPTIMAL ALGEBRAIC IMMUNITY

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Journal of Systems Science & Complexity 2014年第4期27卷 785-794页

作者： WU Baofeng LIU Zhuojun JIN Qingfang zhang xiaoming State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences Key Laboratory of Mathematics Mechanization.Academy of Mathematics and Systems Science Chinese Academy of Sciences Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of Sciences

Tu and Deng proposed a class of bent functions which are of optimal algebraic immunity under the assumption of a combinatorial *** this paper,the authors compute the dual of the Tu-Deng functions and then show that they are still of optimal algebraic immunity under the assumption of the same *** another class of Boolean functions constructed by Tang,et *** are of optimal algebraic immunity with similar forms to Tu-Deng functions,the authors show that they are not bent functions by using some basic properties of binary complete Kloosterman sums.

关键词： Algebraic immunity bent function Boolean function Kloosterman sums Walsh trans-form.