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Science China(Technological Sciences) 2019年第4期62卷 569-577页

作者： wang hongbo LI HaoFei WU YuanHao YANG JianHai LIU WenGuang School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The fibrotic response plays an important role in the performance and longevity of implantable devices. Thus, development of effective anti-inflammatory and anti-fibrosis biomaterial implants has become an urgent task. In this work, we developed a novel supramolecular polymer hydrogel through the copolymerization of N-acryloyl glycinamide(NAGA) and carboxybetaine acrylamide(CBAA) in the absence of any chemical crosslinker, which the mechanical properties being tunable through changing the monomer concentration and the monomer ratio over a broad scope. The hydrogel possessed the superior mechanical performances: high tensile strength(～1.13 MPa), large stretchability(～1200%), and excellent compressive strength(～9 MPa) at high monomer concentration and NAGA/CBAA ratio. Introduction of CBAA could promote the self-healability, thermoplasticity of suparmolecular polymer hydrogels at lower temperatures, meanwhile dramatically improving anti-fouling *** analysis and in vitro cytotoxicity assays testified the excellent biocompatibility of the hydrogel. This high strength supramolecular polymer hydrogel with integrated multiple functions holds promising potentials as a scaffold biomaterial for treating degenerated soft supporting tissues.

关键词： supramolecular polymer hydrogel self-healing anti-protein absorption fibrotic response

Flamelet-like models applied in scramjet combustors:A state of art and prospect

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Chinese Journal of Aeronautics 2023年第10期36卷 24-43页

作者： Tao TANG Zhenguo wang Yuhui HUANG Mingbo SUN hongbo wang Guoyan ZHAO Jiangfei YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Equipment Project Management Center Equipment Development DepartmentBeijing 100089China

Developing supersonic combustion models with efficiency,accuracy and practicality is important foundation to deeply understand the complex combustion processes in scramjet *** by efficiency and intuition,the flamelet-like models are widely used models in computational combustion ***,the supersonic combustion flow field has the nature of strong compressibility,multiple modality,and multiple scales,which poses a great challenge to the traditional flamelet-like models with fixed boundary conditions,and then the complex chemical reaction mechanisms that may face will impose additional computational *** this context,this paper reviews the flamelet-like models used in scramjet engines,and summarizes prominent issues in the application practice,including modeling partially premixed combustion,defining progress variable,solving temperature efficiently,evaluating assumed Probability Density Function(PDF)models,and treating mixture fraction ***,possible prospects and directions of improvements are proposed and highlighted for the flamelet-like *** fully describe the physicochemical scenario and address the raised challenges,these improvements are dedicated to dealing with the compressibility,temperature rise,time-scales,species of interest,multi-inlet combustion,the progress variable definition,and the higher Mach number flight condition.

关键词： Combustion model Flamelet-like model Model improvements Supersonic combustion Scramjet

Virtual Machine Scheduling for Improving Energy Efficiency in laaS Cloud

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China Communications 2014年第3期11卷 1-12页

作者： DONG Jiankang wang hongbo LIYangyang CHENG Shiduan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876China

In IaaS Cloud,different mapping relationships between virtual machines(VMs) and physical machines(PMs) cause different resource utilization,so how to place VMs on PMs to reduce energy consumption is becoming one of the major concerns for cloud *** existing VM scheduling schemes propose optimize PMs or network resources utilization,but few of them attempt to improve the energy efficiency of these two kinds of resources *** paper proposes a VM scheduling scheme meeting multiple resource constraints,such as the physical server size(CPU,memory,storage,bandwidth,etc.) and network link capacity to reduce both the numbers of active PMs and network elements so as to finally reduce energy *** VM scheduling problem is abstracted as a combination of bin packing problem and quadratic assignment problem,which is also known as a classic combinatorial optimization and NP-hard ***,we design a twostage heuristic algorithm to solve the issue,and the simulations show that our solution outperforms the existing PM- or network-only optimization solutions.

关键词： IaaS cloud virtual machinescheduling energy efficiency bin packingproblem quadratic assignment problem

Large eddy simulation of supersonic flow in ducts with complex cross-sections

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Theoretical & Applied Mechanics Letters 2023年第6期13卷 432-440页

作者： Huifeng Chen Mingbo Sun Dapeng Xiong Yixin Yang Taiyu wang hongbo wang Hypersonic Technology Laboratory National University of Defense TechnologyChangsha 410073China

Large Eddy Simulation(LES)has been employed for the investigation of supersonic flow characteristics in five ducts with varying cross-sectional *** numerical results reveal that flow channel configurations exert a considerable influence on the mainstream flow and the near-wall flow *** contrast to straight ducts,square-to-circular and rectangular-to-circular ducts exhibit thicker boundary layers and a greater presence of vortex *** the same inlet area,rectangular-to-circular ducts lead to higher flow drag force and total pressure loss than square-to-circular *** by the substantial flow separation and shock waves,the"S-shaped duct shows significant vertically-asymmetric characteristics.

关键词： Scramjet LES Complex cross-section Boundary layer

A Bacterial Cytochrome P450 Enzyme Catalyzes Multistep Oxidation Reactions in Pyrroindomycin Biosynthesis

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Chinese Journal of Chemistry 2023年第19期41卷 2439-2445页

作者： Jiabao wang Yu Xu Dandan Chen Jiang Tao hongbo wang Wen Liu Department of Chemistry Shanghai Normal University100 Guiling RoadShanghai200233 China State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences345 Lingling RoadShanghai200032 China Department of General Dentistry Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Research Institute of Stomatology639 Zhizaoju RoadShanghai200011 China

Cytochrome P450 enzymes (P450s) belong to a large family of oxidative hemeproteins and catalyze highly diverse oxygenation reactions that are involved in the biosynthesis of various natural products. Here, we report a multifunctional cytochrome P450 enzyme, PyrE2, which catalyzes the regioselective, successive 6-electron oxidation of an inert methyl group to produce a carboxyl product through formation of the hydroxyl and aldehyde intermediates in pyrroindomycin biosynthesis. The time-course biotransformation was characterized by the presence of the hydroxyl and aldehyde intermediates, the lag of the formation of the carboxyl product, and the subsequent loss of both intermediates, indicating that each 2-electron oxidation exhibits the distributive mechanism that requires substrate binding and product releasing. Bioinformatics analysis shows that the homologs of pyrE2 are common in the gene clusters of the spirotetronates varying in the oxidative state of the corresponding exocyclic carbon, indicating the generality and diversity of P450-catalyzed oxygenation in related biosynthetic pathways.

关键词： Cytochrome P450 enzyme Pyrroindomycin Multistep oxidation reactions Enzyme catalysis Selectivity

Application of Improved Multi-Objective Ant Colony Optimization Algorithm in Ship Weather Routing

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Journal of Ocean University of China 2021年第1期20卷 45-55页

作者： ZHANG Guangyu wang hongbo ZHAO Wei GUAN Zhiying LI Pengfei State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China CRRC Changchun Railway Vehicles Co. Ltd.Changchun 130000China

This paper presents a novel intelligent and effective method based on an improved ant colony optimization(ACO)algorithm to solve the multi-objective ship weather routing optimization problem,considering the navigation safety,fuel consumption,and sailing *** the improvement of the ACO algorithm is mainly reflected in two ***,to make the classical ACO algorithm more suitable for long-distance ship weather routing and plan a smoother route,the basic parameters of the algorithm are improved,and new control factors are ***,to improve the situation of too few Pareto non-dominated solutions generated by the algorithm for solving multi-objective problems,the related operations of crossover,recombination,and mutation in the genetic algorithm are introduced in the improved ACO *** final simulation results prove the effectiveness of the improved algorithm in solving multi-objective weather routing optimization *** addition,the black-box model method was used to study the ship fuel consumption during a voyage;the model was constructed based on an artificial neural *** parameters of the neural network model were refined repeatedly through the historical navigation data of the test ship,and then the trained black-box model was used to predict the future fuel consumption of the test *** with other fuel consumption calculation methods,the black-box model method showed higher accuracy and applicability.

关键词： multi-objective optimization weather routing ACO algorithm fuel consumption

Effect of injection scheme on asymmetric phenomenon in rectangular and circular scramjets

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Chinese Journal of Aeronautics 2023年第1期36卷 216-230页

作者： Guangwei MA Mingbo SUN Guoyan ZHAO Changhai LIANG hongbo wang Jiangfei YU Science and Technology on Scramjet Laboratory National University of Defense TechnologyChangsha 410073China

The asymmetric separation has a crucial effect on the performance of the *** this study,the asymmetric separation and combustion in both rectangular and circular scramjets are investigated numerically,and the effect of injection scheme is *** characteristics of the flow field are analyzed based on sufficient code *** the rectangular scramjet,the separation tends to occur in the corner due to the corner boundary-layer *** separation is asym-metric and only two corners have serious *** fuel penetration depth in the separation zone increases and the combustion is *** the injection scheme is uniform,both the combustion and separation become *** the circular scramjet,the separation and combustion are basically axisymmetric in the scramjet with one-row injection *** asymmetric combustion becomes obvious in cases with multi-row injection *** the injection orifices distribute intensively on the top and bottom sides,the strongest and weakest separations occur near these two sides *** the distribution of orifices becomes uniform,the direction of separation cannot be *** multi-row cases,the nonuniform injection scheme could result in violent combustion and asymmetric flow structures compared with the uniform injection scheme.

关键词： Asymmetric phenomenon Cavity Combustion Injection scheme Scramjet Supersonic

Cold Start Problem of Vehicle Model Recognition under Cross-Scenario Based on Transfer Learning

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Computers, Materials & Continua 2020年第4期63卷 337-351页

作者： hongbo wang Qian Xue Tong Cui Yangyang Li Huacheng Zeng State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China National Engineering Laboratory for Public Safety Risk Perception and Control China Academy of Electronics and Information TechnologyBeijing100041China University of Louisville LouisvilleKY40292US

As a major function of smart transportation in smart cities,vehicle model recognition plays an important role in intelligent *** to the difference among different vehicle models recognition datasets,the accuracy of network model training in one scene will be greatly reduced in another ***,if you don’t have a lot of vehicle model datasets for the current scene,you cannot properly train a *** address this problem,we study the problem of cold start of vehicle model recognition under *** the condition of small amount of datasets,combined with the method of transfer learning,load the DAN(Deep Adaptation Networks)and JAN(Joint Adaptation Networks)domain adaptation modules into the convolutional neural network AlexNet and ResNet,and get four models:AlexNet-JAN,AlexNet-DAN,ResNet-JAN,and ResNet-DAN which can achieve a higher accuracy at the *** experiments,transfer the vehicle model recognition from the network image dataset(source domain)to the surveillance-nature dataset(target domain),both Top-1 and Top-5 accuracy have been improved by at least 20%.

关键词： Vehicle model recognition transfer learning cold start and artificial intelligence

Effect of kerosene injection states on mixing and combustion characteristics in a cavity-based supersonic combustor

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Chinese Journal of Aeronautics 2024年第4期37卷 308-320页

作者： Xu LIU Peibo LI Fei LI hongbo wang Mingbo SUN Chao wang Yixin YANG Dapeng XIONG Yanan wang Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

It has been found that the static pressure distribution along the axial direction of liquid kerosene is lower than that of the gaseous kerosene under the same flow condition and overall equivalent ratio from previous *** further investigate this phenomenon,a compressible two-phase parallel simulation method is utilized to analyze the mixing and combustion characteristics of gaseous and liquid kerosene jets in a cavity-based supersonic *** numerical results are consistent with the experiments and demonstrate that gaseous injection leads to a cavity shear layer that dives deeper into the cavity,forming two recirculation zones in the front and rear of the *** contrast,the cavity shear layer is closer to the mainstream during liquid injection,and only a large recirculation zone is formed in the rear of the *** a result of the cavity shear layer and the recirculating flow,the fuel vapor of gaseous injection accumulates in the front of the cavity,while for the liquid injection,the fuel vapor disperses in the cavity,cavity shear layer,and the region above,and the rear of the cavity has a higher fuel vapor concentration than the *** unique fuel distribution causes the combustion area to be concentrated in the cavity during the gaseous injection but dispersed inside and downstream of the cavity during the liquid *** a result,forming a thermal throat under the same conditions is more challenging during liquid injection,and the generated static pressure distribution is lower than that during the gaseous injection.

关键词： Gaseous injection Liquid injection Mixing process Combustion Supersonic flow

Kinetic modeling of dilute solid-liquid two-phase flows with inelastic collisions

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Chinese Science Bulletin 2009年第23期54卷 4358-4364页

作者： FU XuDong SUN QiCheng wang GuangQian MA hongbo State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

A kinetic model was presented for dilute solid-liquid two-phase flows with inelastic collisions by modeling the inelastic collisions with the revised BGK model (Santos and Astillero, 2005) and particle turbulence interactions with the Fokker-Planck operator. The formulated model kinetic equation was solved with the Chapman-Enskog method and the obtained approximate solution was further adopted to derive the constitutive relationships for the conservation equations of the particle phase. The new constitutive relationships would be suitable for the study on dilute solid-liquid two-phase flows such as sediment-laden flows in open channels or rivers.

关键词：非弹性碰撞动力学建模固液两相流动动力学模型方程模型本构关系 BGK模型