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Chinese Physics B 2018年第5期27卷 534-538页

作者： hang yin ying Shi Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

Time-dependent density functional theory(TDDFT)method is used to investigate the details of the excited state intramolecular proton transfer(ESIPT)process and the mechanism for temperature effect on the Enol^(*)/Keto^(*)emission ratio for the Me_(2)N-substited flavonoid(MNF)*** geometric structures of the S_(0) and S_(1) states are denoted as the Enol,Enol^(*),and Keto*.In addition,the absorption and fluorescence peaks are also *** is noted that the calculated large Stokes shift is in good agreement with the experimental ***,our results confirm that the ESIPT process happens upon photoexcitation,which is distinctly monitored by the formation and disappearance of the characteristic peaks of infrared(IR)spectra involved in the proton transfer and in the potential energy ***,the calculations of highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)reveal that the electronegativity change of proton acceptor due to the intramolecular charge redistribution in the S_(1) state induces the ***,the thermodynamic calculation for the MNF shows that the Enol^(*)/Keto^(*)emission ratio decreasing with temperature increasing arises from the barrier lowering of ESIPT.

关键词： time-dependent density functional theory excited state intramolecular proton transfer intramolecular charge transfer transition state

Free Vibration Analysis of Moderately-Thick Laminated Doubly-Curved Shells with the Modified Higher-Order Theory

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Acta Mechanica Solida Sinica 2023年第1期36卷 132-142页

作者： Yuan Tao Jie Xu Xuegang Yuan hang yin School of Mathematics Boda College of Jilin Normal UniversitySiping 136000China Department of Mechanics Northeastern UniversityShenyang 110819China School of Science Dalian Minzu UniversityDalian 116600China

In this work,the free vibration properties ofmoderately-thick laminated doubly-curved shells are *** model of the natural frequency of the simply-supported laminated doubly-curved shell is formulated via the variational *** on the numerical solutions,the influences of the shell type,the aspect ratio,the lamination angle and the layer number on the free vibration are *** obtained results show that,for the symmetrically laminated curved shells with fixed thickness,when the layer number is greater than 4,the increasing number has no impact on the natural frequency;however,the lamination angle plays a key role in the fundamental frequency of the spherical shell,while it has little effect on the hyperbolic paraboloid ***,a higher-order shear deformation theory with modified parameters is developed for the moderately-thick laminated doubly-curved shells in this work,i.e.,the geometrically nonlinear strain–displacement relationships are derived with a stricter series expansion form,which are more suitable for the moderately-thick curved shells.

关键词： Vibration analysis Laminated doubly-curved shell Modified displacement fields Higher-order shear deformation

Human resource allocation for multiple scientific research projects via improved pigeon-inspired optimization algorithm

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Science China(Technological Sciences) 2021年第1期64卷 139-147页

作者： LIU ChuanBin MA YongHong yin hang YU LeAn School of Economics and Management Harbin Engineering UniversityHarbin 150001China Science and Technology Development Center Ministry of EducationBeijing 100080China

Aiming at the complex and restrictive characteristics of human resource allocation in multiple scientific university research projects, an improved pigeon-inspired optimization(IPIO) algorithm is proposed wherein loss minimization and the shortest project delay time are considered as optimization goals. Firstly, mathematical modelling of the problem is carried out, and the multi-objective optimization problem is transformed into a single-objective optimization problem by means of a weighted solution. In the second step, the traditional pigeon-inspired optimization(PIO) algorithm is discretized, and an adaptive parameter strategy is adopted to improve the shortcomings of the algorithm itself. Finally, by comparing the simulation results with the original algorithm and the genetic algorithm in the optimization of human resource allocation in multiple projects, the feasibility and superiority of the proposed algorithm in the optimization of human resource allocation in multi-scientific research projects is verified.

关键词： human resource allocation multiple scientific research projects improved pigeon-inspired optimization(IPIO)algorithm parameter adaptation

On parametric approach of aerial robots' visual navigation

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Journal of Systems Engineering and Electronics 2008年第5期19卷 1010-1016页

作者： Zhou Yu Huang Xianlin Jie Ming yin hang Harbin Inst. of Technology Harbin 150001 P. R. China

In aerial robots＇ visual navigation, it is essential yet very difficult to detect the attitude and position of the robots operated in real time. By introducing a new parametric model, the problem can be reduced from almost unmanageable to be partly solved, though not fully, as per the requirement. In this parametric approach, a multi-scale least square method is formulated first. By propagating as well as improving the parameters down from layer to layer of the image pyramid, a new global feature line can then be detected to parameterize the attitude of the robots. Furthermore, this approach paves the way for segmenting the image into distinct parts, which can be realized by deploying a Bayesian classifier on the picture cell level. Comparison with the Hough transform based method in terms of robustness and precision shows that this multi-scale least square algorithm is considerably more robust to noises. Some discussions are also given.

关键词： parametric model aerial robots visual navigation multi-scale least square.

An LMI-based decoupling control for electromagnetic formation flight

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Chinese Journal of Aeronautics 2015年第2期28卷 508-517页

作者： Huang Xianlin Zhang Chun Lu Hongqian yin hang Center for Control Theory and Guidance Technology Harbin Institute of Technology

Electromagnetic formation flight （EMFF） leverages electromagnetic force to control the relative position of satellites. EMFF offers a promising alternative to traditional propellant-based spacecraft flight formation. This novel strategy is very attractive since it does not consume fuel. Due to the highly coupled nonlinearity of electromagnetic force, it is difficult to individually design a controller for one satellite without considering others, which poses challenges to communications. This paper is devoted to decoupling control of EMFF, including regulations, constraints and con- troller design. A learning-based adaptive sliding mode decoupling controller is analyzed to illustrate the problem of existing results, and input rate saturation is introduced to guarantee the validity of frequency division technique. Through transformation, the imposed input rate saturation is con- verted to state and input constraints. A linear matrix inequalities （LMI）-based robust optimal con- trol method can then be used and improved to solve the transformed problem. Simulation results are presented to demonstrate the effectiveness of the proposed decoupling control.

关键词： Decoupling control Electromagnetic forces Electromagnetic formationflight Linear matrix inequalities Satellite control

Dynamic behaviors of the lump solutions and mixed solutions to a(2+1)-dimensional nonlinear model

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Communications in Theoretical Physics 2023年第5期75卷 52-61页

作者： Si-Jia Chen Xing Lü Yu-hang yin Department of Mathematics Beijing Jiaotong UniversityBeijing 100044China Beijing Laboratory of National Economic Security Early-warning Engineering Beijing Jiaotong UniversityBeijing 100044China

In this paper,we propose a combined form of the bilinear Kadomtsev-Petviashvili equation and the bilinear extended(2+1)-dimensional shallow water wave equation,which is linked with a novel(2+1)-dimensional nonlinear *** model might be applied to describe the evolution of nonlinear waves in the *** the effect of a novel combination of nonlinearity and dispersion terms,two cases of lump solutions to the(2+1)-dimensional nonlinear model are derived by searching for the quadratic function solutions to the bilinear ***,the one-lump-multi-stripe solutions are constructed by the test function combining quadratic functions and multiple exponential *** one-lump-multi-soliton solutions are derived by the test function combining quadratic functions and multiple hyperbolic cosine *** behaviors of the lump solutions and mixed solutions are analyzed via numerical *** result is of importance to provide efficient expressions to model nonlinear waves and explain some interaction mechanism of nonlinear waves in physics.

关键词： bilinear form test function mixed solutions dynamic behaviors

Effects of Sealing Flow Supply Configuration with Holes on Sealing Effectiveness of Turbine Rim Seal

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Journal of Thermal Science 2023年第1期32卷 366-386页

作者： GAI Zepeng ZHU Pengfei HU Jianping LIU Zhenxia yin hang School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

This paper proposes a new-designed rim seal configuration with sealing holes based on the conventional radial rim seal,and presents a numerical comparison of the sealing performance between the conventional sealing flow supply configuration and the new sealing flow supply configuration with holes at different sealing flow *** sealing effectiveness and unsteady flow yields at the rim seal are numerically simulated by using the URANS method and SST turbulent model from ANSYS *** influence of the new sealing flow supply configuration on the sealing effectiveness at different sealing flow rates is *** effectiveness of different sealing flow rates in the conventional rim seal is also *** to the conventional rim seal,the increase in the sealing flow rate reduces the degree of gas ingestion induced by the effect of mainstream ingress at the rim clearance,while the unsteady flow characteristics are enhanced,and the number and amplitude of the low-frequency signals *** position of the Kelvin-Helmholtz instabilities vortex structures is left by the increased sealing flow rate,and its strength is *** with the conventional rim seal configuration,the new sealing flow supply configuration with holes could reduce the sealing efficiency by 5.06%at most at sealing flow distribution m_(1):m_(2)=3:1 when Cw=2000,and improve the sealing efficiency by 11.71%at most at sealing flow distribution m_(1):m_(2)=1:1 when Cw=*** shows that the lateral jet from the holes induces a larger-scale Kelvin-Helmholtz vortex structure at Cw=2000,thus the sealing efficiency in the wheel space is also ***,the size of the Kelvin-Helmholtz vortex structures is significantly suppressed by the new sealing flow supply configuration at Cw=7500,which is beneficial to improving the sealing effectiveness of the conventional rim seal.

关键词： secondary air system rim seal ingestion and seal unsteady flow discrete sealing holes

Body-Fitted Momentum Source Method for Predicting Rotor Aerodynamics Characteristics in Hover

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第4期36卷 641-651页

作者： LI Peng KONG Xiaojun yin hang Zhang Guangjun Shanghai Institute of Mechanical and Electrical Engineering Shanghai 201109P.R.China

To gain high efficiency for the simulation of the aerodynamic characteristics of the rotor in hover,body?fitted momentum source(BFMS)method is *** this method,the actual blade geometry is represented by the single layer of volume grid surrounding the *** at correctly simulating the aerodynamic characteristics of the discrete cells along the chordwise of blade airfoil section,a new distributed force model is *** comparison,the RANS method with S?A turbulence model and the steady rotor momentum source(SRMS)method based on embedded grid systems are established,*** the grid connecting methodology is improved to embed the blade into the background grids for the three ***,simulations are performed for the hovering Caradonna?Tung rotor by these methods,and the calculated results are compared with the available experimental ***,the pressure distributions along the blade are compared with the conventional momentum source *** is demonstrated that the BFMS method can be employed as an effective approach to predict rotor aerodynamic characteristics with a low computational resource and reasonable accuracy.

关键词： rotor momentum source body⁃fitted CFD embedded grid system

Efects of idle time on biological phosphorus removal by sequencing batch reactors

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Journal of Environmental Sciences 2013年第12期25卷 2396-2402页

作者： Dawen Gao hang yin Lin Liu Xing Li Hong Liang School of Forestry Northeast Forestry University State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Institute of Urban Environment Chinese Academy of Sciences

Three identical sequencing batch reactors （SBRs） were operated to investigate the effects of various idle times on the biological phosphorus （P） removal. The idle times were set to 3 hr （R1）, 10 hr （R2） and 17 hr （R3）. The results showed that the idle time of a SBR had potential impact on biological phosphorus removal, especially when the influent phosphorus concentration increased. The phosphorus removal efficiencies of the R2 and R3 systems declined dramatically compared with the stable R1 system, and the Prelease and P-uptake rates of the R3 system in particular decreased dramatically. The PCR-DGGE analysis showed that uncultured Pseudomonas sp. （GQ183242.1） and β-Proteobacteria （AY823971） were the dominant phosphorus removal bacteria for the R1 and R2 systems, while uncultured γ-Proteobacteria were the dominant phosphorus removal bacteria for the R3 system. Glycogen-accumulating organisms （GAOs）, such as uncultured Sphingomonas sp. （AM889077）, were found in the R2 and R3 systems. Overall, the R1 system was the most stable and exhibited the best phosphorus removal efficiency. It was found that although the idle time can be prolonged to allow the formation of intracellular polymers when the phosphorus concentration of the influent is low, systems with a long idle time can become unstable when the influent phosphorus concentration is increased.

关键词： biological phosphorus removal polyphosphate-accumulating organisms idle time microbial community

Hierarchical Dragonfly Wing： Microstructure-Biomechanical Behavior Relations

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Journal of Bionic Engineering 2012年第2期9卷 185-191页

作者： yinglong Chen Xishu Wang Huaihui Ren hang yin Su Jia Department of Engineering Mechanics AML School of Aerospace Tsinghua University Beijing 100084 P. R. China Beijing Aeronautical Engineering Technology Center Beijing 100076 P. R. China

The dragonfly wing, which consists of veins and membrane, is of biological hierarchical material. We observed the cross-sections of longitudinal veins and membrane using Environmental Scanning Electron Microscopy （ESEM）. Based on the experiments and previous studies, we described the longitudinal vein and the membrane in terms of two hierarchical levels of organization of composite materials at the micro- and nano-scales. The longitudinal vein of dragonfly wing has a complex sandwich structure with two chitinous shells and a protein layer, and it is considered as the first hierarchical level of the vein. Moreover, the chitinous shells are concentric multilayered structures. Clusters of nano-fibrils grow along the circumferential orientation embedded into the protein layer. It is considered as the second level of the hierarchy. Similarly, the upper and lower epidermises of membrane constitute the first hierarchical level of organization in micro scale. Similar to the vein shell, the membrane epidermises were found to be a paralleled multilayered structure, defined as the second hierarchical level of the membrane. Combining with the mechanical behavior analysis of the dragonfly wing, we concluded that the growth orientation of the hierarchical structure of the longitudinal vein and membrane is relevant to its biomechanical behavior.

关键词： dragonfly wing longitudinal vein membrane hierarchical structure biomechanical behavior