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Up-conversion emissions of Er^(3.)-Yb^(3.) codoped Al_2O_3.nanoparticles by the arc discharge synthesis method

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, WANG XingJun2, LI ChengRen3.& HUA RuiNian4 1 school of science, Dalian Nationalities university, Dalian 116600,{3. 2 school of Electronics Engineering and computer science, Peking university, Beijing 100871,{3. 3.College of Physics and Electronic technology, Liaoning Normal university, Dalian 116029,{3. 4 College of Life science, Dalian Nationalities university, Dalian 116600,{3. 1. school of science Dalian Nationalities University Dalian 116600 China 2. school of Electronics Engineering and computer science Peking University Beijing 100871 China 3. College of Physics and Electronic technology Liaoning Normal University Dalian 116029 China 4. College of Life science Dalian Nationalities University Dalian 116600 China

The Er3.-Yb3. codoped Al2O3.nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H11/2→4I15/2, 4S3.2→4I15/2 and 4 F9/2→4I15/2 transitions of Er3., were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3.l5O12 and α-(Al,Er,Yb)2O3.phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I11/2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3.)+4I11/2(Er3.)→2F7/2(Yb3.)+4F7/2(Er3.) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3.-Yb3. codoped Al2O3 arc discharge synthesis

User-perceived e-mail service QoS parameters and measurement

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The Journal of china Universities of posts and telecommunications 2010年第3期17卷 85-90页

作者： LI Yong-zhi , LIU Feng, LEI Zhen-ming, CHEN Ling school of Information and Communication Engineering, Beijing university of posts and {3., Beijing 100876, china [a] school of Information Communication Engineering Beijing University of Posts telecommunications Beijing 100876 China

A group of quality of service （QoS） parameters of electronic mail （e-mail） traffic are proposed from users＇ perspective. These parameters cover three fields： delay, throughput and usability. Concept and algorithm of each parameter are presented and its effect on user perceptions is described. In order to evaluate the effectiveness of these parameters, an active measurement system is implemented. Measured results show that the group of QoS parameters we proposed can be used to get a comprehensive view of user-perceived e-mail service QoS.

关键词： user perceptions e-mail service QoS active measurement

Distributed GEP query optimization on grid service

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The Journal of china Universities of posts and telecommunications 2010年第3期17卷 118-122,128页

作者： DENG Yong, WANG Ru-chuan College of computer, Nanjing university of posts and {3., Nanjing 210003. china [a] College of computer Nanjing University of Posts telecommunications Nanjing 210003 China

In order to better solve the problem of distributed query optimization, a query optimization algorithm on gene expression programming （GEP）（QO-GEP） is presented. On the basis of QO-GEP, distributed GEP query optimization on grid service （DGEPQO-GS） is proposed which combines grid service. Simulated experiments show that with the increment of the number of query relation, query time which QO-GEP carries out query decreases apparently. Meanwhile, with the increase of the number of grid nodes, the average querying success rate of DGEPQO-GS increases significantly.

关键词： gene expression programming distributed query grid service query relation

A novel model-free approach for reconstruction of time-delayed gene regulatory networks

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中国科学：生命科学英文版 2006年第2期49卷 190-200页

作者： JIANG Wei1,2, LI Xia1,2,3.4, GUO Zheng1,2,3. LI Chuanxing1, WANG Lihong1 & RAO Shaoqi1,5 1. Department of Bioinformatics, Harbin Medical university, Harbin 150086, china 2. Department of computer {3., Harbin Institute of technology, Harbin 150080, china 3. school of Life {3. and technology, Tongji university, Shanghai 200092, china 4. Biomedical Engineering Institute, Capital university of Medical {3.s, Beijing 100054, china 5. Departments of Cardiovascular Medicine and Molecular Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA Department of Bioinformatics Harbin Medical University Harbin 150086 China Department of computer science Harbin Institute of Technology Harbin 150080 China school of Life science technology Tongji University Shanghai 200092 China Biomedical Engineering Institute Capital University of Medical Sciences Beijing 100054 China Departments of Cardiovascular Medicine Molecular Cardiology Cleveland Clinic Foundation Cleveland Ohio 44195 USA

Reconstruction of genetic networks is one of the key scientific challenges in functional genomics. This paper describes a novel approach for addressing the regulatory dependencies be-tween genes whose activities can be delayed by multiple units of time. The aim of the proposed ap-proach termed TdGRN (time-delayed gene regulatory networking) is to reversely engineer the dy-namic mechanisms of gene regulations, which is realized by identifying the time-delayed gene regu-lations through supervised decision-tree analysis of the newly designed time-delayed gene expres-sion matrix, derived from the original time-series microarray data. A permutation technique is used to determine the statistical classification threshold of a tree, from which a gene regulatory rule(s) is ex-tracted. The proposed TdGRN is a model-free approach that attempts to learn the underlying regula-tory rules without relying on any model assumptions. Compared with model-based approaches, it has several significant advantages: it requires neither any arbitrary threshold for discretization of gene transcriptional values nor the definition of the number of regulators (k). We have applied this novel method to the publicly available data for budding yeast cell cycling. The numerical results demonstrate that most of the identified time-delayed gene regulations have current biological knowledge supports.

关键词： gene regulatory networks, time delayed, decision tree.

Structure splitting framework for data-layout optimization

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The Journal of china Universities of posts and telecommunications 2009年第5期16卷 107-113页

作者： FU Xiong , WANG Ru-chuan College of computer, Nanjing university of posts and {3., Nanjing 210003. china [a]College of computer Nanjing university of posts and telecommunications Nanjing 210003 china

To improve data cache performance, optimizing program data layout by data reorganization has become an important method of decreasing the impact of increasing gap of speed between processor and memory. In this article, a structure splitting framework with an analysis model named structure field relation graph （SFRG） is presented to optimize program data layout. The SFRG can be used to quantify relationship between fields. It helps to find an optimal layout for structure as well as the optimal program data layout. And the data cache performance is improved through SFRG-based structure splitting. Experiments show that this framework is effective in optimizing program data layout and improving the performance of data cache and whole program.

关键词： program optimization structure splitting data layout cache performance

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

Automatic composition of information-providing web services based on query rewriting

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science china(Information sciences) 2012年第11期55卷 2428-2444页

作者： ZHAO WenFeng,LIU ChuanChang & CHEN JunLiang State Key Laboratory of Networking and Switching technology,Beijing university of posts and {3.,Beijing 100876,china 1. State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing 100876 China

Compared with normal web services,information-providing services have unique features that have seldom been considered in existing research on the automatic composition of web *** this paper,we present a simple,yet well-formed,semantic-based capability model for information-providing web services,which can express such features as not modifying the world state and not requiring all input/output parameters to be supplemented with class information as *** then present a corresponding automatic composition method derived from a query rewriting algorithm,MiniCon,used in the data integration *** method adequately utilizes previous features,enables primitive semantic reasoning,and can generate executable BPEL scripts *** of the method is complementary to traditional search-based *** on a typical type of problem show that the method is usable in practice.

关键词： web services automatic composition query rewriting data integration ontology semantic web

QoS routing based on mobile agent for LEO satellite IP networks

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The Journal of china Universities of posts and telecommunications 2009年第6期16卷 57-63页

作者： RAO Yuan,WANG Ru-chuan College of computer,Nanjing university of posts and {3.,Nanjing 23.001,china [a] College of computer Nanjing university of posts and telecommunications Nanjing 23.001 china

Current quality of service（QoS） routing schemes for low earth orbit（LEO） satellites IP networks either neglect the varying population density or fail to guarantee end-to-end *** a remedy,QoS routing protocol based on mobile agent（QoSRP-MA） is ***-MA is a source-based routing *** connection requests arrive,QoS mobile agents are dispatched from ingress satellite to explore routes,which migrate using satellite routing *** arriving in egress satellite,QoS mobile agents migrate back towards ingress satellite to reserve *** construct satellite routing tables,load balancing routing algorithm based on mobile agent（LBRA-MA） is *** LBRP-MA,at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing ***,path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link（ISL） ***,ISL congestion index is considered to update routing *** simulations on a Courier-like constellation,it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput,lower connection failing ratio and signaling overhead compared to high performance satellite routing（HPSR） scheme.

关键词： QoS routing load balancing mobile agent satellite IP networks

Restoration method of characters on Jiagu rubbings based on Poisson distribution and fractal geometry

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science china(Information sciences) 2010年第7期53卷 1296-1304页

作者： GU ShaoTong1,2,3. FENG GeFei1,2,3. MA XiaoHu1,2,4 & YANG YiMing1,2,3.1Institute of Linguistics, Xuzhou Normal university, Xuzhou 221009, china 2Jiangsu College Key Lab of Linguistic sciences and Neuro-cognition Engineering, Xuzhou Normal university, Xuzhou 221009, china 3.inguistic science College, Xuzhou Normal university, Xuzhou 221009, china 4school of computer science and technology, Soochow university, Suzhou 215006, china 1. Institute of Linguistics Xuzhou Normal University Xuzhou 221009 China2. Jiangsu College Key Lab of Linguistic Sciences and Neuro-cognition Engineering Xuzhou Normal University Xuzhou 221009 China3. Linguistic Science College Xuzhou Normal University Xuzhou 221009 China4. School of Computer Science and Technology Soochow University Suzhou 215006 China

A scheme for character restoration of Jiagu rubbings based on Poisson distribution and fractal geometry is proposed in this paper. The distribution characteristics of the connected regions on Jiagu rubbings is analyzed, and all the connected regions are recognized according to differences between these and their mathematical expectations. Regions are recognized as noise regions and filled if the differences are negative, while stroke regions are reserved. The attributes of the character image edges on Jiagu rubbings are also analyzed. The fractal dimensions of the character edge of Jiagu rubbings are calculated by means of statistics. The feature points are obtained using the cosine of the angle between the two vectors of the point and the consecutive two points. Different compression transformations with weighted coordinates are performed on different strokes and segments of the characters so as to smoothen the character edge of Jiagu rubbings images. Experimental results show that our scheme could successfully clear noise regions and polish the character edge of Jiagu rubbings.

关键词： Jiagu rubbings Poisson distribution fractal geometry fractal dimension compression transformation character restoration