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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,university of science and technology Beijing,Beijing 100083,china

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of science and technology Beijing,Beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

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L1/2 regularization

science china(Information sciences) 2010年第6期53卷 1159-1169页

作者： XU ZongBen 1 , ZHANG Hai 1,2 , WANG Yao 1 , CHANG XiangYu 1 & LIANG Yong 3 1 Institute of Information and System science, Xi'an Jiaotong university, Xi'an 710049, china 2 Department of Mathematics, Northwest university, Xi'an 710069, china 3 university of science and technology, macau 999078, china Institute of Information and System science Xi’an Jiaotong University Xi’an China Department of Mathematics Northwest University Xi’an China university of science and technology Macau China

In this paper we propose an L1 /2 regularizer which has a nonconvex *** L 1/2 regularizer is shown to have many promising properties such as unbiasedness, sparsity and oracle properties.A reweighed iterative algorithm is proposed so that the solution of the L 1/2 regularizer can be solved through transforming it into the solution of a series of L 1 *** solution of the L 1/2 regularizer is more sparse than that of the L 1 regularizer, while solving the L 1/2 regularizer is much simpler than solving the L 0 *** experiments show that the L 1/2 regularizer is very useful and efficient, and can be taken as a representative of the Lp(0 < p < 1) regularizer.

关键词： machine learning variable selection regularizer compressed sensing

Image science technology Forecasting on offset printing: A Patent Analysis Approach

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仪器仪表学报 2004年第S3期25卷 43-47+66页

作者： Liu Yaojen (Department of Graphic communication and technology, Shih Hsin university,Taipei, china) Department of Graphic communication and technology Shih Hsin University Taipei China

technology forecasting is a important approach which can help researcher to point out what will be of technology in the future. There are many well-developed approaches and methodologies can do technology forecasting well, for example S-curve *** analysis is another way to analyze technology development trend. Patent is a kind of intellectual property right can help researcher avoid to infringe patent owned by competitor. Patent analysis can help researcher and corporate find out what are major technology trends and point out what field has low patent infringement risk. It will describe what patent analysis is briefly and how to process, and use patent analysis to analysis image reproduction technology trend. Offset printing technology is the main field discussed. When running analysis will follow the international patent classification (IPC) category and use USPTO patent database.

关键词： Offset printing Patent analysis technology technology forecasting

EFFECT OF BIAS STRESS ON NON-LINEAR INTERNAL FRICTION OF Al-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 166-171页

作者： TAN Qi university of science and technology of china,Hefei,china Univ of science and technology of China Hefei China

The influence of longitudinal and torsional bias stresses on anomalous amplitude-dependent internal friction was *** longitudinal bias stress may always weaken the anomalous amplitude-dependent effect,while the torsional one may induce different effects from differ- ent directions *** stress effect exhibits only in properly heat treated and cold worked ahoy *** anomalous amplitude-dependent internal friction peaks,P_3,P_2 and P_1, are found to be related closely to slant dislocation kink ***,the application of bias stress to internal friction would be contributed to the study on dislocation structure.

关键词： internal friction bias stress anomalous amplitude effect dislocation kink

The Theoretical Basis of Modern High Agrobiolgical science and technology

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农业生物技术学报 2004年第2期12卷 119-120页

作者： WU Zhong-Xian(alias J.S.) Ph. D Professor (College of Animal science and technology, china Agricultural university, Beijing 100094, china) College of Animal science and technology China Agricultural University 北京 100094

Philosophy of zero: Zero and its Interactions; O-rigin of 0 and 1. Consciousness: Classification of Consciousness: Consciousness of Stones, Conscious ness of Amoeba, Consciousness of Man, Conscious ness of Angels, Consciousness of God (Monadism of Leibniz). Relations between Man and Consciousness: Logical, birth of Logic, i.e. Deduction, discovered in Greece and perfected by Aristotle. Quantitative, birth of numbers, discovered by Arabians. Discovery of 0, the greatest World Mathematician, supposed to be the Hindus, mentioned by Bramagupta. Birth of Interac tions: Example: Interaction of 0 and 0: 0 + 0, 0 - 0, 0x0,0-^0, the last term indefinite, birth of something new. Discoverer of the Calculus is Newton. Besides, he discovered Universal Gravitation. Interaction of and 2: 1 Absolute; 2 Relative. Relativeness + Universal Gravitation = birth of Einstein's Relativity. Which is greater, Einstein or Newton? Answer: Einstein is greater since he discovered both Relativity and Quantum Theory which changed our entire view of the universe.

关键词： The Theoretical Basis of Modern High Agrobiolgical science and technology 遗传学报

Dynamic behavior of micro-diaphragms and its characterized description

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science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1345-1356页

作者： GE LiFeng School of Electronic science and technology, Anhui university, Hefei 230039, china School of Electronic science and technology Anhui University Hefei China

Diaphragm structures with micron scale play a significant role in microtransducers and micro-nano devices, and the performance of these devices depends mainly on the dynamic behaviour of diaphragms. Micro-diaphragms are treated commonly as membranes and in some cases as plates or plates in tension (called TD plates for short), but they also show in many cases the behaviour of plates in tension and supported by air spring (called TDK plates for short). Therefore, it is necessary to perform systematic research on the dynamic behaviour of micro-diaphragms, and establish a characterized mathematical description. This paper focuses on the TDK plates since they possess universality, gives the corresponding basic equations, and then derives analytical solutions of TDK circular plates under clamped and simply supported boundary conditions. This paper also gives a 3D plot representation of characteristic curved surfaces, revealing the transition from the TDK and TD plate to the pure plate or pure membrane behaviour; and further uses the value φ to determine the property of diaphragms. Its two extreme cases, i.e. φ = 0 and φ = ∞ , correspond to pure plate or pure membrane, respectively. Thus, membrane, plate and TD plate can be treated as special cases of TDK plate. In addition, this paper reveals that the presence of air-spring not only enhances the restoring force of diaphragm such that increases its natural frequencies, but also results in the resonance of a dynamic system consisting of diaphragm and air-spring. These analytical and computational results are significant for the understanding of the operation mechanism of capacitive microtransducers and their optimized design.

关键词： micro-diaphragm membrane and plate TD plate and TDK plate dynamic behaviour characterized description

Epidemic dynamics on complex networks

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Progress in Natural science:Materials International 2006年第5期16卷 452-457页

作者： ZHOU Tao , FU Zhongqian, and WANG Binghong (Department of Electronic science and technology, university of science and technology of china, Hefei 230026, china Department of Modern Physics, university of science and technology of china, Hefei 230026, china) Department of Electronic science and technology University of Science and Technology of China Hefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

Recently, motivated by the pioneer work in revealing the small-world effect and scale-free property of various real-life networks, many scientists devote themselves to studying complex networks. One of the ultimate goals is to understand how the topological structures affect the dynamics upon networks. In this paper, we give a brief review on the studies of epidemic dynamics on complex networks, including the description of classical epidemic models, the epidemic spread on small-world and scale-free networks, and network immunization. Finally, perspectives and some interesting problems are proposed.

关键词： epidemic dynamics complex networks critical value immunization small-world effect scale-free property.

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science School, university of science and technology Beijing, Beijing 100083, china) Applied science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

Production of O' -sialon-SiC Composites by Carbon Reduction-Nitridation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 26-30页

作者： Haijun Zhang Wenchao Li Xiangcong Zhong (Applied science School, university of science and technology Beijing, Beijing 1 0008 3, china) Applied science School University of Science and Technology Beijing Beijing 100083 China

The effect of temperature, soak times, carbon and addition on composites was discussed in the process ofsynthesizing O'-sialon-SiC by carbonthermal reduction-nitration from nature kaolin. It showed that the fracturestrength (MOR) of composites sintered under certain conditions can be up to 140MPa at room temperature. Thetarget parameter optima regions with good mechanical properties of this material were also indicated by usingcomputer pattern recognition program.

关键词： O'-sialon-SiC compostites carbonthermal reduction-nitration pattern recognition program