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Journal of Hydrodynamics 2019年第4期31卷 669-681页

作者： Ying Guo Li-qin Liu Yan Li Chang-shui Xiao you-gang tang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China

The motions of the floating vertical axis wind turbine (VAWT) with consideration of the coupling between the aerodynamics and the hydrodynamics are calculated in this paper. The surge-heave-pitch coupling nonlinear equations of the floating VAWT are established. The aerodynamic loads are obtained by applying the double-multiple-stream tube theory with consideration of the dynamic stall and the floating foundation motion. The motion performances of a 5 MW Φ - Darrieus type floating VAWT are studied with its foundation of the Spar type with heave plates. It is shown that the amplitude of the heave motion of the floating VAWT is small when the heave plates are equipped. The effects of the wind and wave loads on the floating VAWT motions are assessed. The results show that the mean values of the surge and the pitch of the floating VAWT are mainly related to the wind loads;the standard deviations of the surge, the heave, and the pitch are mainly related to the wave loads. In the regular wave cases, the frequencies of the surge, the heave and the pitch are dominated by the wave frequencies, and the components of the 2P responses (caused by the aerodynamic loads) of the pitch are small. The 2P responses of the pitch are more significant in the irregular wave cases as compared with those in the regular wave cases.

关键词： Floating VAWT truss Spar floating foundation surge-heave-pitch motions aerodynamics regular waves irregular waves

Study of the natural vibration characteristics of water motion in the moon pool by the semi-analytical method

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Journal of Hydrodynamics 2017年第1期29卷 124-134页

作者：刘利琴李妍黄磊唐友刚 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

The three-dimensional natural vibration characteristics of water inside a moon pool of an ocean structures are studied. The governing equations are derived based on the linear potential flow theory, and the boundary condition of the total opening bottom suggested by Molin is adopted. A semi-analytical method is used to solve the governing equations, and the natural frequencies and the motion modes are obtained. Two types of motions are studied：（1） the piston motion in the vertical direction, and （2） the sloshing motion of the free surface. The influences of moon pool＇s structural parameters on the natural frequencies, and the modal shapes are analyzed.

关键词： Moon pool natural vibration characteristics semi-analytical method parameter influences

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曲面射线管在复杂电磁环境预测中的应用

北京邮电大学学报 2018年第1期41卷 103-108页

作者：吕娜石丹姜炜高攸纲唐朝汉北京邮电大学电子工程学院北京100876 温州市铁路与轨道交通投资集团有限公司浙江温州325000

提出了一种新型的曲面射线管应用于射线追踪中的绕射射线路径预测.相比于现有的四边形波前面绕射射线管,曲面射线管能够在追踪的过程中有效地减少计算时间,提高追踪效率.通过理论分析推导,证明该模型相比于四边形射线管,在采用的追踪实... 详细信息

提出了一种新型的曲面射线管应用于射线追踪中的绕射射线路径预测.相比于现有的四边形波前面绕射射线管,曲面射线管能够在追踪的过程中有效地减少计算时间,提高追踪效率.通过理论分析推导,证明该模型相比于四边形射线管,在采用的追踪实例中计算效率提高了约4倍.详细介绍了特殊凹陷地形与射线管求交的处理情况.通过基于四边形波前面射线管和曲面射线管的不同算法计算,对追踪时间和结果进行了对比,曲面射线管的平均计算时间缩短了约18.49%,平均误差仅为2.93%,效率得到了提高,也验证了追踪结果路径的准确性.

关键词：曲面射线管射线追踪射线传播绕射路径电磁仿真

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-tang Liang Yu-gang Ma Xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Internal Resonances for Heave, Roll and Pitch Modes of A Spar Platform Considering Wave and Vortex-Induced Loads in the Main Roll Resonance

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China Ocean Engineering 2017年第4期31卷 408-417页

作者： LI Wei tang you-gang LIU Li-qin LI Yan WANG Bin State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China School of Civil Engineering Tianjin University Tianjin 300072 China Coltabomtive Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240 China

We present a study of the nonlinear coupling internal resonance for the heave roll and pitch performance of a spar platform under the wave and vortex-induced loads when the ratio of the frequencies of heave, roll and pitch are approximately 2：1：1. In consideration of varying wet surface, the three DOFs nonlinear coupled equations are established for the spar platform under the effect of the first-order wave loads in the heave and pitch, and vortex-induced loads in the roll. By utilizing the method of multi-scales when the vortex-induced frequency is close to the natural roll frequency, the first-order perturbation solution is obtained analytically and further validated by the numerical integration. Sensitivity analysis is performed to understand the influence of the damping and the internal detuning parameter. Two cases with internal resonance are shown. The first case is that no saturation phenomenon exists under small vortex-induced loads. The first order perturbation solution illustrates that only the vortex-induced frequency motion in roll and the super-harmonic frequency motion in heave are excited. The second case is that the vortex-induced loads are large enough to excite the pitch and a saturation phenomenon in the heave mode follows. The results show that there is no steady response occurrence for some cases. For these cases chaos occurs and large amplitudes response can be induced by the vortex-induced excitation.

关键词： spar platform three DOFs nonlinear equations multiple scales super-harmonic response energy infiltration

Studies on Stochastic Parametric Roll of Ship with Stochastic Averaging Method

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China Ocean Engineering 2020年第2期34卷 289-298页

作者： WANG Li-yuan tang you-gang LI Yan ZHANG Jing-chen LIU Li-qin School of Civil Engineering Tianjin UniversityTianjin 300072China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

The paper studies the parametric stochastic roll motion in the random *** differential equation of the ship parametric roll under random wave is established with considering the nonlinear damping and ship *** sea surface is treated as a narrow-band stochastic process,and the stochastic parametric excitation is studied based on the effective wave *** nonlinear restored arm function obtained from the numerical simulation is expressed as the approximate analytic *** using the stochastic averaging method,the differential equation of motion is transformed into Ito’s stochastic differential *** steady-state probability density function of roll motion is obtained,and the results are validated with the numerical simulation and model test.

关键词： parametric roll random wave stochastic averaging method probability density function

A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves

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China Ocean Engineering 2018年第1期32卷 74-84页

作者： LIU Li-qin LIU Ya-liu XU Wan-hai LI Yan tang you-gang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

The PDFs(probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA(2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship’s manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas.

关键词： ship random rolling parametric and forced excitations stochastic energy envelope averaging method probability density function parameter influence analysis

A Novel Belief Rule-Based Fault Diagnosis Method with Interpretability

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1165-1185页

作者： Zhijie Zhou Zhichao Ming Jie Wang Shuaiwen tang you Cao Xiaoxia Han gang Xiang Rocket Force University of Engineering Xi’an710025China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Beijing Aerospace Automatic Control Institute Beijing100070China

Fault diagnosis plays an irreplaceable role in the normal operation of equipment.A fault diagnosis model is often required to be interpretable for increasing the trust between humans and the *** to the understandable knowledge expression and transparent reasoning process,the belief rule base(BRB)has extensive applications as an interpretable expert system in fault *** is an effective means to weaken the subjectivity of experts in BRB,where the interpretability of BRB may be ***,to obtain a credible result,the weakening factors of interpretability in the BRB-based fault diagnosis model are firstly analyzed,which are manifested in deviation from the initial judgement of experts and over-optimization of *** these two factors,three indexes are proposed,namely the consistency index of rules,consistency index of the rule base and over-optimization index,tomeasure the interpretability of the *** both the accuracy and interpretability of amodel,an improved coordinate ascent(I-CA)algorithmis proposed to fine-tune the parameters of the fault diagnosis model based on *** I-CA,the algorithm combined with the advance and retreat method and the golden section method is employed to be one-dimensional search ***,the random optimization sequence and adaptive step size are proposed to improve the accuracy of the ***,a case study of fault diagnosis in aerospace relays based on BRB is carried out to verify the effectiveness of the proposed method.

关键词： Fault diagnosis belief rule base interpretability weakening factors improved coordinate ascent

Review on artificial intelligence techniques for improving representative air traffic management capability

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1123-1134页

作者： tang Jun LIU gang PAN Qingtao College of Systems Engineering National University of Defense TechnologyChangsha 410073China School of InformationScience and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

The use of artificial intelligence(AI)has increased since the middle of the 20th century,as evidenced by its applications to a wide range of engineering and science *** traffic management(ATM)is becoming increasingly automated and autonomous,making it lucrative for AI *** paper presents a systematic review of studies that employ AI techniques for improving ATM capability.A brief account of the history,structure,and advantages of these methods is provided,followed by the description of their applications to several representative ATM tasks,such as air traffic services(ATS),airspace management(AM),air traffic flow management(ATFM),and flight operations(FO).The major contribution of the current review is the professional survey of the AI application to ATM alongside with the description of their specific advantages:(i)these methods provide alternative approaches to conventional physical modeling techniques,(ii)these methods do not require knowing relevant internal system parameters,(iii)these methods are computationally more efficient,and(iv)these methods offer compact solutions to multivariable *** addition,this review offers a fresh outlook on future *** is providing a clear rationale for the model type and structure selection for a given ATM *** is to understand what makes a specific architecture or algorithm effective for a given ATM *** are among the most important issues that will continue to attract the attention of the AI research community and ATM work teams in the future.

关键词： artificial intelligence(AI) air traffic management(ATM) air traffic services(ATS) airspace management(AM) air traffic flow management(ATFM) flight operations(FO)

A Review on Representative Swarm Intelligence Algorithms for Solving Optimization Problems:Applications and Trends

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IEEE/CAA Journal of Automatica Sinica 2021年第10期8卷 1627-1643页

作者： Jun tang gang Liu Qingtao Pan College of Systems Engineering National University of Defense TechnologyChangsha 410000China School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

Swarm intelligence algorithms are a subset of the artificial intelligence(AI)field,which is increasing popularity in resolving different optimization problems and has been widely utilized in various *** the past decades,numerous swarm intelligence algorithms have been developed,including ant colony optimization(ACO),particle swarm optimization(PSO),artificial fish swarm(AFS),bacterial foraging optimization(BFO),and artificial bee colony(ABC).This review tries to review the most representative swarm intelligence algorithms in chronological order by highlighting the functions and strengths from 127 research *** provides an overview of the various swarm intelligence algorithms and their advanced developments,and briefly provides the description of their successful applications in optimization problems of engineering ***,opinions and perspectives on the trends and prospects in this relatively new research domain are represented to support future developments.

关键词： Ant colony optimization(ACO) artificial bee colony(ABC) artificial fish swarm(AFS) bacterial foraging optimization(BFO) optimization particle swarm optimization(PSO) swarm intelligence