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Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2, CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, beijing Normal university, beijing 100875, china 2 beijing Radiation center, beijing 100875, china 3 Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, beijing 100080, china 4 Key Laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, tsinghua university, beijing 100084, china 5 beijing national center for electron microscopy, tsinghua university, beijing 100084, china 1. Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing Radiation center Beijing 100875 China 3. Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. beijing national center for electron microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2, 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2+ and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2+, Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2+ and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2+ and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

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2023 Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of Chinese Geriatrics Society,beijing Hypertension Association,national Clinical Research center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina Chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

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Preparation of NiFe binary alloy nanocrystals for nonvolatile memory applications

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Science china(Technological Sciences) 2010年第9期53卷 2320-2322页

作者： WANG Li,SUN HongFang,ZHOU HuiHua & ZHU Jing beijing national center for electron microscopy Laboratory,Department of Materials Science and Engineering,tsinghua university,beijing 100084,china 1. beijing national center for electron microscopy Laboratory Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

In this work,an idea which applies binary alloy nanocrystal floating gate to nonvolatile memory application was *** relationship between binary alloy’s work function and its composition was discussed theoretically.A nanocrystal floating gate structure with NiFe nanocrystals embedded in SiO2 dielectric layers was fabricated by magnetron *** micro-structure and composition deviation of the prepared NiFe nanocrystals were also investigated by TEM and EDS.

关键词： nanocrystal nonvolatile memory work function magnetron sputtering

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Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, Department of Physics, tsinghua university, beijing 100084, china center for Quantum Information, tsinghua university, beijing 100084, china Department of Materials Science and Engineering, beijing Normal university, beijing 100875, china Testing and Analytical center, beijing Normal university, beijing 100875, china Department of Physics, beijing Normal university, beijing 100875, china 1. Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University 100084 Beijing China 2. center for Quantum Information Tsinghua University 100084 Beijing China 3. Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 4. Testing and Analytical center Beijing Normal University 100875 Beijing China 5. Department of Physics Beijing Normal University 100875 Beijing China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

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A measurement error model for microarray data analysis

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Progress in Natural Science:Materials International 2005年第7期15卷 614-620页

作者： ZHOU Yiming and CHENG Jing ( Department of Biological Sciences and Biotechnology, tsinghua university, beijing 100084, china State Key Laboratory of Biomembrane and Membrane Biotechnology, tsinghua university, beijing 100084, china national Engineering Research center for beijing Biochip Technology, 18 Life Science Parkway, beijing 102206, china) Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China. State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing 100084 China. national Engineering Research center for beijing Biochip Technology 18 Life Science Parkway Beijing 102206 China

Microarray technology has been widely used to analyze the gene expression levels by detecting fluorescence intensity in a high throughput fashion. However, since the measurement error produced from various sources in microarray experiments is heterogeneous and too large to be ignored, we propose here a measurement error model for microarray data processing, by which the standard deviation of the measurement error is demonstrated to be linearly increased with fluorescence intensity. A robust algorithm, which estimates the parameters of the measurement error model from a single microarray without replicated spots, is provided. The model and algorithm for estimating of the parameters from a given data set are tested on both the real data set and the simulated data set, and the result has been proven satisfactory. And, combining the measurement error model with traditional Z-test method, a full statistical model has been developed It can significantly improve the statistical inference for identifying differentially expressed genes.

关键词： microarray measurement error model parameter estimation differentially expressed genes.

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Scheduling of Development Projects with Uncertain Iterations

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Journal of Systems Engineering and electronics 2001年第2期12卷 82-86页

作者： Yan Jihong & Wu Cheng national CIMS Engineering Research center, tsinghua university, beijing 100084, P R. china national CIMS Engineering Research center Tsinghua University Beijing 100084 P. R. China

This paper studies the scheduling of design projects in concurrent development process with uncertain number of feedback revisions. An optimization based methodology that combines heuristic algorithm, artificial intelligence (fuzzy, genetic algorithm) and scheduling theory is developed. In the algorithm, weighting values of some key factors are defined by genetic algorithm. In addition, fuzzy logic is used to decide the ability coefficients of different roles taken by designers. Moreover, the process of pre-release and feedback revision is realized. Simulation example is a fraction of practical development project, and satisfied results are obtained.

关键词： Concurrent engineering Product development process Optimization scheduling.

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RESEARCH ON CAPP/SCHEDULING INTEGRATION MULTI-AGENT SYSTEM MODEL AND IMPLEMENTATION

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Chinese Journal of Mechanical Engineering 2003年第4期16卷 348-351页

作者： Wang YunliXiao TianyuanDuan GuanghongWang Xiankuinational CIMS EngineeringResearch center,tsinghua university,beijing 100084, china national CIMS Engineering Research center Tsinghua University Beijing 100084 China

A design methodology for multi-agent systems is proposed. The systemicframework of CAPP and scheduling integrated multi-agent system according to design methodology isresearched. Agent model, composition model and cooperation model are discussed respectively in themulti-agent system. Static composition model and dynamic running model of CAPP and schedulingintegrated system are presented in composition model. Communication model, language model andprotocol model are discussed in corporation model. CSIMAS, CAPP and scheduling integratedmulti-agent prototype system, is developed to illuminate system model. Multiple non-rotational partsare tested in distributed process planning and scheduling environment of CSIMAS.

关键词： Multi-agent systems Design methodology CAPP Scheduling Integration

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RRM:An incentive reputation model for promoting good behaviors in distributed systems

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Science in china(Series F) 2008年第11期51卷 1871-1882页

作者： ZHANG Hong1,2,DUAN HaiXin1,3 & LIU Wu1,3 1 tsinghua national Laboratory for Information Science and Technology,tsinghua university,beijing 100084,china 2 Department of Computer Science and Technology,tsinghua university,beijing 100084,china 3 Network Research center,tsinghua university,beijing 100084,china 1. tsinghua national Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China 2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China 3. Network Research center Tsinghua University Beijing 100084 China

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the conversational reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to maximize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security

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Extremal eigenvalues of measure differential equations with fixed variation

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Science china Mathematics 2010年第10期53卷 2573-2588页

作者： ZHANG MeiRong 1,2 1 Department of Mathematical Sciences,tsinghua university,beijing 100084,china 2 Zhou Pei-Yuan center for Applied Mathematics,tsinghua university,beijing 100084,china 1. Department of Mathematical Sciences Tsinghua University Beijing 100084 China2. Zhou Pei-Yuan Center for Applied Mathematics Tsinghua University Beijing 100084 China

In this paper we will study eigenvalues of measure differential equations which are motivated by physical problems when physical quantities are not absolutely *** taking Neumann eigenvalues of measure differential equations as an example,we will show how the extremal problems can be completely solved by exploiting the continuity results of eigenvalues in weak* topology of measures and the Lagrange multiplier rule for nonsmooth *** results can give another explanation for extremal eigenvalues of SturmLiouville operators with integrable potentials.

关键词： measure differential equation eigenvalue extremal value weak* topology Frechét derivative sub-differential

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Explicit Classification for Torsion Subgroups of Rational Points of Elliptic Curves

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Acta Mathematica Sinica,English Series 2002年第3期18卷 539-548页

作者： De Rong QIU center for Advanced Study, tsinghua university, beijing 100084. P. R. china Xian Ke ZHANG Department of Mathematical Sciences, tsinghua university, beijing 100084, P. R. china center for Advanced Study Tsinghua University Beijing P. R. China Department of Mathematical Sciences Tsinghua University Beijing P. R. China

We study the classification of elliptic curves E over the rationals Q according to the torsion subgroups E_(tors)(Q). More precisely, we classify those elliptic curves with E_(tors)(Q) being cyclic with even orders. We also give explicit formulas for generators of E_(tors)(Q). These results, together with the recent results of K. Ono for the non-cyclic E_(tors)(Q), completely solve the problem of the explicit classification and parameterization when E has a rational point of order 2.

关键词： Elliptic curve Rational point Torsion group Mordell group Parameterization

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