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Optical propagation through non-Kolmogorov turbulence

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Science China(Information Sciences) 2013年第4期56卷 69-74页

作者： TANG Hua OU baolin School of Electronic and Information Engineering Beihang University

In this paper,the effects of the generalized exponent,the height and the zenith angle on the log-amplitude variance in the weak fluctuation are *** theoretical results indicate that for the downlink,the log-amplitude variance of the Kolmogorov model is always smaller than that of the three-layer model,while for the uplink,there is a point of intersection in the log-amplitude variance curves of the two *** different phenomena for the downlink and uplink are analyzed in ***,we find a method to ascertain precise values of the boundary layer altitudes for the three-layer model under various atmospheric conditions through the analysis for the point of *** at the point of intersection,the Kolmogorov model can be used to replace the three-layer model to simplify the analysis of the system ***,the log-amplitude variance increases with the increase of the zenith angle.

关键词： atmospheric turbulence three-layer model log-amplitude variance power spectral density generalized exponent

Distributed QoS multicast routing protocol in ad hoc networks

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Journal of Systems Engineering and Electronics 2006年第3期17卷 692-698页

作者： Sun baolin Li Layuan School of Computer Science and Technology Wuhan Univ. of Technology Wuhan 430063 P. R. China Dept. of Mathematics and Physics Wuhan Univ. of Science and Engineering Wuhan 430073 P. R. China

Quality of service （QoS） routing and multicasting protocols in ad hoc networks are face with the challenge of delivering data to destinations through multihop routes in the presence of node movements and topology changes. The multicast routing problem with multiple QoS constraints is discussed, which may deal with the delay, bandwidth and cost metrics, and describes a network model for researching the ad hoc networks QoS multicast routing problem. It presents a distributed QoS multicast routing protocol （DQMRP）. The proof of correctness and complenty analysis of the DQMRP are also given. Simulation results show that the multicast tree optimized by DQMRP is better than other protocols and is fitter for the network situations with frequently changed status and the realtime multimedia application. It is an available approach to multicast routing decision with multiple QoS constraints.

关键词： ad hoc network multicast routing routing protocol QoS.

Numerical investigation of Richtmyer-Meshkov instability driven by cylindrical shocks

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Acta Mechanica Sinica 2006年第1期22卷 9-16页

作者： baolin Tian Dexun Fu Yanwen Ma LNM Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper, a numerical method with high order accuracy and high resolution was developed to simulate the Richtmyer-Meshkov（RM） instability driven by cylindrical shock waves. Compressible Euler equations in cylindrical coordinate were adopted for the cylindrical geometry and a third order accurate group control scheme was adopted to discretize the equations. Moreover, an adaptive grid technique was developed to refine the grid near the moving interface to improve the resolution of numerical solutions. The results of simulation exhibited the evolution process of RM instability, and the effect of Atwood number was studied. The larger the absolute value of Atwood number, the larger the perturbation amplitude. The nonlinear effect manifests more evidently in cylindrical geometry. The shock reflected from the pole center accelerates the interface for the second time, considerably complicating the interface evolution process, and such phenomena of reshock and secondary shock were studied.

关键词： Richtmyer-Meshkov instability Atwoodnumber cylindrical shock

Singularity radius gradient-based rapid singularity-escape steering law for SGCMGs

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Chinese Journal of Aeronautics 2020年第10期33卷 2728-2742页

作者： Tao YI Yunhai GENG baolin WU Research Center of Satellite Technology Harbin Institute of TechnologyHarbin 150080China

In order to visualize singularity of SGCMGs in gimbal angle space,a novel continuous bounded singularity parameter--Singularity Radius,whose sign can distinctly determine singularity type,is *** a rapid singularity-escape steering law is proposed basing on gradient of Singularity Radius and residual base vector to drive the SGCMG system to neighboring singular boundary,and quickly escape elliptic ***,simulation results on Pyramid-type and skew-type configuration demonstrate the effectiveness and rapidness of the proposed steering law.

关键词： Gaussian curvature Rapid singularity escape Single gimbal control moment gyroscope Singularity-escape steering law Singularity parameter Singularity type

Synthetic biodegradable functional polymers for tissue engineering:a brief review

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Science China Chemistry 2014年第4期57卷 490-500页

作者： GUO baolin MA Peter X Center for Biomedical Engineering and Regenerative Medicine Frontier Institute of Science and Technology Xi'an Jiaotong University Department of Biomedical Engineering University of Michigan Department of Biologic and Materials Sciences University of Michigan Macromolecular Science and Engineering Center University of Michigan Department of Materials Science and Engineering University of Michigan

Scaffolds play a crucial role in tissue engineering. Biodegradable polymers with great processing flexibility are the predominant scaffolding materials. Synthetic biodegradable polymers with well-defined structure and without immunological concerns associated with naturally derived polymers are widely used in tissue engineering. The synthetic biodegradable polymers that are widely used in tissue engineering, including polyesters, polyanhydrides, polyphosphazenes, polyurethane, and poly(glycerol sebacate) are summarized in this article. New developments in conducting polymers, photoresponsive polymers, amino-acid-based polymers, enzymatically degradable polymers, and peptide-activated polymers are also discussed. In addition to chemical functionalization, the scaffold designs that mimic the nano and micro features of the extracellular matrix(ECM) are presented as well, and composite and nanocomposite scaffolds are also reviewed.

关键词： synthetic biodegradable polymers functional polymers scaffolds tissue engineering

Transport diffuse interface model for simulation of solid-fluid interaction

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 321-330页

作者： Li LI Qian CHEN baolin TIAN Institute of Applied Physics and Computational Mathematics

For solid-fluid interaction, one of the phase-density equations in diffuse interface models is degenerated to a "0 = 0" equation when the volume fraction of a certain phase takes the value of zero or unity. This is because the conservative variables in phasedensity equations include volume fractions. The degeneracy can be avoided by adding an artificial quantity of another material into the pure phase. However, nonphysical waves,such as shear waves in fluids, are introduced by the artificial treatment. In this paper,a transport diffuse interface model, which is able to treat zero/unity volume fractions, is presented for solid-fluid interaction. In the proposed model, a new formulation for phase densities is derived, which is unrelated to volume fractions. Consequently, the new model is able to handle zero/unity volume fractions, and nonphysical waves caused by artificial volume fractions are prevented. One-dimensional and two-dimensional numerical tests demonstrate that more accurate results can be obtained by the proposed model.

关键词： solid-fluid interaction diffuse interface model phase-density equation Mie-Gruneisen equation of state(EOS) Eulerian method

Using two-pass friction stir processing to produce nanocrystalline microstructure in AZ61 magnesium alloy

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Science China(Technological Sciences) 2009年第6期52卷 1751-1755页

作者： XingHao Du baolin Wu Department of Materials Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

Despite their interesting properties,nanostructured materials have found limited use as a result of the cost of preparation and the difficulty in scaling ***,a two-pass friction stir processing(FSP)technique is employed to refine grain sizes to a *** AZ61 Mg alloy with an av-erage grain size of less than 100nm was successfully obtained using *** to this,the highest microhardness of the nano-grained region reached triple times that of AZ61 *** prin-ciple,by applying multiple overlapping passes,it should be possible to produce any desired size thin sheet of nanostructure using this *** expect that the FSP technique may pave a way to large-scale structural applications of nanostructured metals and alloys.

关键词： AZ61 Mg alloy friction stir processing nano-grained microstructure microhardness

Relationship of Old World Pseudoxenodon and New World Dipsadinae,with Comments on Underestimation of Species Diversity of Chinese Pseudoxenodon

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Asian Herpetological Research 2013年第3期4卷 155-165页

作者： baolin ZHANG Song HUANG College of Life and Environment Sciences Huangshan University School of Life Sciences Yunnan University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences Institute of Biodiversity and Geobiology Department of Life SciencesTibet University

Assessment of the relationship between Pseudoxenodon and Dipsadinae has been hampered by lack of adequate samples. In this paper, we conducted phylogenetic analyses using two mitochondrial genes （12S and 16S rRNA） and one nuclear gene （c-mos） from thirteen specimens representing two species of Pseudoxenodon, together with 84 sequences of caenophidians and an outgroup sequence of Boa constrictor. Our study suggests that the Southeast Asian genus, Pseudoxenodon forms a robust genetic subclade within South American xenodontines, indicating that at least one lineage within this genus entered or returned to the Old World （OW） from the New World （NW） across the Beringian Land Bridge during the early Tertiary and the warm mid-Miocene. It also reveals the high intraspecific genomic variation within the populations of Pseudoxenodon macrops, indicating that species diversity of Pseudoxenodon in China is likely underestimated.

关键词： phylogenetic position 12S rRNA 16S rRNA Beringian Land Bridge cryptic species

Anti-plane pull-out of a rigid line inclusion from an elastic medium

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Applied Mathematics and Mechanics(English Edition) 2023年第5期44卷 809-822页

作者： Yansong WANG baolin WANG Youjiang CUI Kaifa WANG Harbin Institute of Technology Shenzhen Campus Harbin Institute of TechnologyHarbin 150001China

The transient and static anti-plane problem of a rigid line inclusion pulled out from an elastic medium is *** singular integral equation method is used to solve the stress *** the static load,the stress intensity factor(SIF)at the inclusion tips increases with the medium *** problem becomes equivalent to an inclusion in a medium with an infinite length when the length of the medium is 3.5times longer than that of the ***,under the transient load,the maximum value of the SIF occurs when the medium length is about two times the inclusion ***,the relation between the pull-out force and the anti-plane displacement is *** conclusions are useful in guiding the design of fiber reinforced composite materials.

关键词： pull-out rigid line inclusion anti-plane stress intensity factor(SIF) stress singularity