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SINE TRANSFORM MATRIX FOR SOLVING TOEPLITZ MATRIX PROBLEMS

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Journal of Computational Mathematics 2001年第2期19卷 167-176页

作者： Li-zhi Cheng (department of Mathematics & System Sciences, National university of Defence Technology, Changsha 410073,{2.) 国防科技大学湖南长沙 410073

Provides information on a study which discussed the properties of eigenvalues for the solutions of symmetric positive definite Toeplitz systems, skew circulant and sine transform based properties. Eigenvalues of various preconditioners; Design of positive sine transform based preconditioners; Clustering property of the preconditioners; Numerical results.

关键词： preconditioner Toeplitz systems the fast sine transform conjugate gradient algorithm

PERFORMANCE AND INITIATION MECHANISM OF ISOPROPYLTHIOXANTHONE IN SURFACE PHOTOGRAFTING

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Chinese Journal of Polymer Science 2000年第5期18卷 431-435页

作者： Wan-tai Yang Mei-zhen Yin Yu-feng Sun College of Material Science and Engineering, beijing university of Chemical Technology, beijing 10002., china beijing Univ Chem Technol Coll Mat Sci & Engn Beijing 100029 Peoples R China

In a polymerization model with low density polyethylene (LDPE) as the substrate and acrylic acid (AA) as the monomer, the performance of isopropylthioxanthone (ITX) in initiating surface photografting polymerization was evaluated. The results show that the reactivity of photopolymerization and photografting of ITX locate between benzophenone (BP) and benzildimethylketal (BDK) for polymerization, BDK > ITX > BP; for surface grafting polymerization, BP > ITX > BDK. These results can be explained by a reaction mechanism of the inter-molecular or intra-molecular hydrogen abstraction reaction of ITX.

关键词： photografting polymerization photopolymerization hydrogen abstraction reaction

A Facile Synthesis of Spin Labeled 4′-Epi-N-Trifuoroactyldaunomycin Derivatives

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Chinese Chemical Letters 2001年第8期12卷 665-666页

作者： Xu Feng LIN, Cheng MA*, Yan Guang WANG department of chemistry, Zhejiang {2., Hangzhou 31002. Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

The spin labeled 4(-Epi-N-trifuoroacetyldaunomycin derivatives 6-7 were conveniently synthesized from daunomycin in middle yield. The key steps were the protection of compd. 5 at 9-position and nucleophilic displaceme... 详细信息

关键词： Spin labeled daunomycin antitumor synthesis.

SPONTANEOUS POLARIZATION AND THE DISTRIBUTION OF INTERNAL STRESS AND ELECTRIC FIELDS AROUND A TRIPLE POINT

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Acta Mechanica Solida Sinica 2000年第1期13卷 1-8页

作者： Zhang Ying (department of Materials Science,Xiamen university,Xiamen 361005,{2.) Xiamen Univ Dept Mat Sci Xiamen 361005 Peoples R China

In this article, distributions of internal stress and internal electric fields around a triple point of ferroelectric polycrystals generated by the spontaneous deformation and spontaneous polarization were investigated. It was found that when all three grains consist of a single domain, the internal stresses and the internal electric fields do not vanish. Though it may be determined according to the principle of energy, the spontaneous configuration will not be unique without involving other conditions due to the symmetry of the crystal structure.

关键词： spontaneous polarization internal stress internal electric field electric domain

Study of OCDs Reliability Estimation System Based on Bio-Immunology

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Journal of Bionic Engineering 2009年第3期6卷 306-310页

作者： Dan-e Wu~1 Qiu-zhan Zhou~1 Ping-ping Liu~2.He-bin Zhang1.College of Communication Engineering,Jilin university,Changehun 13002.,P.R.china2.{2. of Computer Science and Technology,Jilin university,Changchun 130012.P.R.china [a]College of Communication Engineering Jilin University Changchun 130022 P. R. China [b]Department of Computer Science and Technology Jilin University Changchun 130012 P. R. China

We introduce the relationship between excess noise in Optoelectronic Coupled Devices (OCDs) and their interior defects and explain how low-fiequency noise can be used to estimate their *** concepts from the biological immune system and its process of identifying invaders,we present a system for estimation of the reliability of *** system has expressions for the antigen (excess noise),lymphocyte (criterion) and the role of the lymphocyte eliminating unreliable devices. A genetic algorithm was used to estimate the components parameters of the noise spectrum for estimating the reliability of *** experimental results demonstrated that this method is reliable,adaptable and practical.

关键词： low-frequency noise artificial immunity genetic algonthm device reliability

Micromagnetic Simulation of Demagnetization Curves for Single-Phase Nanocrystalline Nd-Fe-B Magnet

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Journal of Materials Science & Technology 2000年第2期16卷 107-108页

作者： Hanmin JIN, Sufen ZHAO and Xuefeng WANG (department of Physics, Jinn university, Changchun 130012.{2.) department of Physics Jilin University Changchun 130012 China

The demangetization curves for the nanocrystalline Nd-Fe-B magnets of the stoichiometric composition were calculated by using the finite element technique of micromagnetism. The curve, especially iHc become smaller with increase of *** most small iHc from a series of the curves along different field directions is closer to that for N=∞. iHc increases with increase of L, and are close cr some what smaller than that the experimental values should be.

关键词： Simulation Nd Fe

Low-temperature optical spectra and zero-phonon transition of color centers in γ-rayed lithium fluoride crystals

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Chinese Journal of Lasers 1993年第5期B2卷 59-63页

作者： Honggen Gu (department of Physics, Tianjin university, Tianjin 300072.{2.) Tianjin Univ Tianjin China

The zero-phonon lines on R2. R~+, N1and R′2.enters and some new narrow lines have been observed in bivalent-metal-doped and air-grown LiF crystals irradiated by γ-ray in the temperature range of 9.5—130K. The spect... 详细信息

关键词： low-temperature spectra zero-phonon transition color-centers in LiF2

COUPLED SOLUTION FOR ANISOTROPIC PIEZOELECTRIC MATERIALS WITH CRACKS

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Acta Mechanica Solida Sinica 1999年第1期12卷 83-90页

作者： Hou Mishan (department of Mechanical Engineering,university of Petroleum,Dongying 2.7062.{2.) department of Mechanical Engineering University of Petroleum Dongying 257062 China

The coupled elastic and electric fields for anisotropic piezoelectric materials with electrically permeable cracks are analyzed by using Stroh formula in anisotropic elasticity. It is shown from the solution that the tangent component of the electric field strength and the normal component of the electric displacement along the faces of cracks are all constants, and the electric field intensity and electric displacement have the singularity of type (1/2. at the crack tip. The energy release rate for crack propagation depends on both the stress intensity factor and material constants. The electric field intensity and electric displacement inside electrically permeable cracks are all constants.

关键词： piezoelectric material crack stress intensify factor energy release rate

A LOW POWER TIME-TO-DIGITAL CONVERTER FOR ALL-DIGITAL PHASE-LOCKED LOOP

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Journal of Electronics(china) 2011年第3期28卷 402-408页

作者： Yu Guangming Wang Yu Yang Huazhong department of Electronic Engineering Tsinghua National Laboratory for Information Science and Technology （ TNList） Tsinghua University Beijing 100084 China

Time-to-Digital Converter (TDC) is a key block used as the phase/frequency detector in an All-Digital Phase-Locked Loop (ADPLL). Usually, it occupies a large proportion of ADPLL's total power consumption up to about 30% to 40%. In this paper, the detailed power consumption of different components in the TDC is analyzed. A Power Management Block (PMB) is presented for the TDC to reduce its power consumption. A 2.-bits TDC core with the proposed PMB is implemented in HJTC 0.18 μm CMOS technology. Simulation results show that up to 84% power reduction is achieved using our proposed technique.

关键词： Low power Power management All-Digital Phase-Locked Loop (ADPLL) Time-to-Digital Converter (TDC)