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A general communication performance evaluation model based on routing path decomposition

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Journal of Zhejiang University-Science C(Computers and electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1,Yun PAN 1,2.Xiao-lang YAN 2.Ruo-hong HUAN 3.(1 department of Information Science and {3. Engineering,Zhejiang University,{2. 3.002.,china) (2.institute of VLSI Design,Zhejiang University,{2. 3.002.,china) (3.College of Computer Science and Technology,Zhejiang University of Technology,{2. 3.002.,china) department of Information Science and electronic Engineering Zhejiang University institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 10 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

SrGa_2._4∶Ce blue TFEL in new structure

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Chinese Science Bulletin 1998年第7期43卷 603-605页

作者： XU Chunxiang+1, LOU Zhidong+2. XU Zheng+3.and XU Xurong+3.. National Laboratory of Molecular and Biomolecular electronics, Southeast University, Nanjing 2.0096,{3. {2. of Applied Physics, Tianjin University, Tianjin 3.003.,{3. 3. Institu National Laboratory of Molecular and Biomolecular electronics Southeast University Nanjina China department of Applied Physics Tianjin University Tianjin China institute of Photoelectronic Technology Northern Jiaotong University Beijing China

SrGa-2.-4∶Ce blue TFEL device with a novel structure was prepared by electron beam evaporation. The dielectric constant of insulator layer in this structure is far less than that in the conventional structure, so the hot-electrons can be accelerated in SiO-2.layers. The stable TFEL with good chromaticity was achieved and the basic characteristics were investigated.

关键词： SrGa-2.-4∶Ce bule TFEL low dielectric constant insulator layer.

electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. institute of Nuclear Physics and Chemistry, china Academy of Engineering Physics, Mianyang 62.900, china 2. department of physics, Peking university, Beijing 100871, china 3. institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, china 1. institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. department of physics Peking university Beijing 100871 China 3. institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2. DU Mengli3.& LIN Shenglu1 1. College of Physics and electronics, Shandong Normal University, Jinan 2.0014,{3. {2. of Mathematics and Physics, Shandong institute of Architecture and Engineering, Jinan 2.0014,{3. 3. institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080,{3. 1. College of Physics and electronics Shandong Normal University 250014 Jinan China 2. department of Mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth Sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2. SONG Linhua1 & BAO Haosheng2.1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101,{3. {2. of Geography, Nanjing University, Nanjing 2.0093.{3. 3. School of Earth Sciences and Resources,{3. University of Geosciences, Beijing 100083.{3. institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China department of Geography Nanjing University Nanjing 210093 China School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

Repetitive learning control of nonlinear systems over finite intervals

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Science china(Information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2.& CHEN PengNian3.1College of Information Engineering, Zhejiang University of Technology, hangzhou 3.0014, china 2.chool of Electrical and {2. Engineering, Nanyang Technological University, Singapore 63.794 3.5} of Mathematics, china institute of Metrology, hangzhou 3.0018, china 1. College of Information Engineering Zhejiang University of Technology Hangzhou 310014 China2. School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639794 Singapore3. Department of Mathematics China Institute of Metrology Hangzhou 310018 China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

Comparison study of trapped water in human erythrocytes by EPC and DSC method and its application

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Science china(Technological Sciences) 2004年第3期47卷 343-351页

作者： ZHAO Gang1, HE Liqun1, GUO Xiaojie2. LIU Zhong3. LUO Dawei1,3.& GAO Dayong1,3.1. Cryobiomedical Engineering Research institute, department of Thermal Science and Energy Engineering, University of Science and Technology of{2., Hefei 2.002.,{2. 2. Red Cross Blood Center of Hefei, Hefei 2.002.,{2. 3. department of Mechanical Engineering, University of Kentucky, Lexington, KY 40506-0108, USA Univ Sci & Technol china Cryobiomed Engn Res Inst Dept Thermal Sci & Energy Engn Hefei 230027 Peoples R China Red Cross Blood Ctr Hefei Hefei 230022 Peoples R China Univ Kentucky Dept Mech Engn Lexington KY 40506 USA

The novel differential scanning calorimetry method for determining trapped water volume of human red blood cell during freezing process has been reexamined. Results show that the final erythrocyte volume is 53. of its isotonic volume after freezing to -40℃. An electronic particle counter (MultisizerTM III, Beckman Coulter Inc., USA) was used to measure cell volume changes in response to hypertonic solution. Using this approach, when extracellular solution was 3.86 mOsm, the equilibrium cell volume was found to be 57% of its isotonic value. Both results indicate that 3.%—40% of intracellular water is trapped and cannot respond to osmotic difference between intra- and extracellular solution. These findings are consistent with the published data: at least 2.%—3.1} of the isotonic cell water volume is retained within RBCs during freezing. Some applications of the values of trapped water are addressed.

关键词： differential scanning calorimeter/DSC, electronic particle counter/EPC, cell volumetric change, red blood cell/RBC/erythrocyte

On the TOPS mode spaceborne SAR

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Science china(Information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2., HONG Wen 3.& MAO ShiYi 2.1 department of {3. Engineering, Beijing {2. of Technology, Beijing 100081, china 2.department of {3. Engineering, Beihang University , Beijing 100191, china 3.{2. of electronics,Chinese Academy of Sciences, Beijing 100190, china 1. department of electronic Engineering Beijing Institute of Technology Beijing 100081 China2. Department of Electronic Engineering Beihang University Beijing 100191 China3. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS

Ultrafast excitation relaxation in light-harvesting complex LH2.from *** 601

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Science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2. LIU Yuan3. LIU Weimin2. GUO Junhua1, XU Chunhe3.& QIAN Shixiong2.1. School of Physics and Information Opto{3., Henan University, Kaifeng 475001, china 2. Physics {2., Fudan University, Shanghai 2.043., china 3. Shanghai institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 2.003.0} china 1. School of Physics and Information Optoelectronics Henan University 475001 Kaifeng China 2. Physics department Fudan University 200433 Shanghai China 3. Shanghai institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2.from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.