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Chinese Journal of Aeronautics 2022年第2期35卷 214-234页

作者： Songyan WANG Fei LIU Tao CHAO Ming YANG Control and Simulation Center Harbin Institute of TechnologyHarbin 150001China

For the solid rocket with depletion shutdown system,effective energy management is significant to meet terminal constraints by exhausting excess energy.Several traditional energy management algorithms cannot satisfy the altitude constraint and path constraints are not sufficiently considered.The velocity adjustment capability of these algorithms is limited and the uncertainties are not considered.Based on the on-line programming of velocity capability curve,Spline-Line Energy Management(SLEM)guidance algorithm is proposed.It introduces lateral maneuvers to further consume the available velocity on the basis of longitudinal energy management.After expressing the constraints as several algebraic equations,the closed-loop guidance problem is converted to solving a system of nonlinear equations about the curve parameters in real time.The advantage is that the altitude constraint can be satisfied theoretically.The overload and control variable change rate and amplitude constraints are also considered during the flight by constructing the feasible boundary of velocity capability curve.To improve the robustness,it is further extended by estimating the actual uncertainties.The effectiveness and advantages of SLEM are demonstrated by simulations and comparisons with other energy management algorithms.Simulation results show that the proposed approach can satisfy multiple constraints with high precision under the condition of uncertainties.

关键词： Ascent guidance Energy management Multiple constraints Solid rockets Uncertainty Velocity capability curve

Modified rolling guidance law for single moving mass controlled reentry vehicle against maneuvering target with impact angle constraints

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Chinese Journal of Aeronautics 2022年第6期35卷 226-239页

作者： Guanlin LI Ming YANG Songyan WANG Tao CHAO Control and Simulation Center Harbin Institute of TechnologyHarbin 150001China

This paper deals with the problem of guidance law design for the single moving mass controlled reentry vehicle when impact angle constraints and maneuvering target are taken into consideration.More specifically,a modified rolling guidance law is proposed with the interactive virtual target and the landing point prediction strategy.First,considering the fact that the roll channel can be controlled directly,the relative motion between the single moving mass controlled reentry vehicle and the target is described by the error angle between the relative velocity and the line-ofsight.Second,a nonlinear error angle command is given to reduce the rotation rate.To satisfy impact angle constraints,an interactive virtual target is presented and the‘‘S”formed velocity of the virtual target is given to abate the error angle tracking difficulty at the final stage of the reentry phase.Then,the landing point prediction strategy is employed and the motion variation trend is also taken into consideration.As the maneuvering target is replaced with the predicted landing point,the error angle tracking difficulty caused by the target velocity decreases,which is helpful to meet impact angle constraints and improve guidance accuracy at the same time.Finally,the finite-time rolling guidance law is proposed and proved via Lyapunov stability theorem.Compared with the existing method,lower-speed rotation,smaller missing distance and less impact angle errors are obtained,which can be demonstrated by numerical simulations.

关键词： Reentry vehicles Guidance law Impact angle Maneuvering target Finite-time convergence

High-precision shape approximation low-thrust trajectory optimization method satisfying bi-objective index

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Chinese Journal of Aeronautics 2022年第1期35卷 436-457页

作者： Ruiye JIANG Ming YANG Songyan WANG Tao CHAO Rajan SHANKARAN Control and Simulation Center Harbin Institute of TechnologyHarbin 150080China Department of Computing Macquarie UniversitySydneyNSW 2109Australia

The shape approximation method has been proven to be rapid and practicable in resolving low-thrust trajectory;however,it still faces the challenges of large deviation from the optimal solution and inability to satisfy the specific flight time and fuel mass constraints.In this paper,a modified shape approximation low-thrust model is presented,and a novel constrained optimization algorithm is developed to solve this problem.The proposed method aims at settling the bi-objective optimization orbit involving the twin objectives of minimum flight time and low fuel consumption and enhancing the accuracy of optimized orbit.In particular,a transformed high-order polynomial model based on finite Fourier series is proposed,which can be characterized as a multi-constraint optimization problem.Then,a novel optimization algorithm is specifically developed to optimize the large-scale multi-constraint dynamical equations of shape trajectory.The key performance indicators of the index include minimum flight time,low fuel consumption and bi-objective optimization of the two.Simulation results prove that this approach possesses both the high precision achievable by numerical methods and low computational complexity offered by shape approximation techniques.Besides,the Pareto front of the fuel-time bi-objective optimization orbit is firstly introduced to analyze an intact optimal solution set.Furthermore,we have demonstrated that our proposed approach is appropriate to generate the preliminary orbit for pseudo-spectral method.

关键词： Constrained optimization Intelligent optimization Low-thrust trajectory Multi-objective optimization Shape approximation method

Linear-quadratic and norm-bounded differential game combined guidance strategy against active defense aircraft in three-player engagement

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Chinese Journal of Aeronautics 2023年第8期36卷 331-350页

作者： Tao CHAO Xintao wang Songyan WANG Ming YANG Control and Simulation Center Harbin Institute of TechnologyHarbin 150080China

A new type of guidance strategy, combining linear quadratic and norm-bounded game theory, is proposed for the scenario of an attacker against active defense aircraft in three-player engagement. The problem involves three players, an attacker, a defender and a target. The differential game theory and the solution of Hamiltonian equation are utilized to obtain the combined guidance strategy for each player with arbitrary-order dynamics. The game process is divided into4 phases, C1-C4, according to the switching time. The linear quadratic differential game guidance scheme is employed to reduce the fuel cost in the game parts of C1 and C3. The norm-bounded game guidance strategy is adopted to satisfy the constraint of control input in the game stages C2 and C4. Furthermore, zero-effort miss distance is introduced to meet the constraints of game space and defender’s killing radius in the guidance strategy, which guarantees that the attacker is able to avoid the interception of the defender and hit the target with lower fuel cost and maximum acceleration. And it is proved that the proposed guidance strategy satisfies the Nash equilibrium condition. Finally, the feasibility and superiority of combined guidance strategy are respectively illustrated by nonlinear numerical simulation and verified by comparing with linear quadratic and norm-bounded differential game guidance strategies.

关键词： Activedefense aircraft Acceleration Energy optimization Game theory Three-player engagement

Implications of Stahl's Theorems to Holomorphic Embedding Part I: Theoretical Convergence

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CSEE Journal of Power and Energy Systems 2021年第4期7卷 761-772页

作者： songyan Li Daniel Tylavsky Di Shi Zhiwei wang School of Electrical Computer and Energy Engineering in Arizona State University TempeAZ 85287USA AINERGY LLC Santa ClaraCA 95051 State Grid Jiangsu Electric Power Company Nanjing 210024China

What is known as StahPs Theorem in power engineering circles is used to justify a convergence guarantee of the Holomorphic Embedding Method(HEM)as it applies to powerflow(PF)problem.In this two-part paper,we examine in more detail the implications of Stahl's theorems to both theoretical and numerical convergence for a wider range of problems to which these theorems are now being applied.We show that the difference between StahPs extremal domain and the function's domain is responsible for theoretical nonconvergence and that the fundamental cause of numerical nonconvergence is the magnitude of logarithmic capacity of the branch cut,a concept central to understanding nonconvergence.We introduce theorems using the necessary mathematical parlance and then translate the language to show its implications to convergence of nonlinear problems in general and specifically to the PF problem.We show that,among other possibilities,the existence of Chebotarev points,which are embedding specific,are a possible theoretical impediment to convergence・The theoretical foundation of Part I is necessary for understanding the numerical behavior of HEM discussed in Part II.

关键词： Analytic continuation holomorphic embedding method power flow Pade approximants HEM Stahl's theorems

Integrated guidance and control design method based on finite-time state observer

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Journal of Systems Engineering and Electronics 2018年第6期29卷 1251-1262页

作者： MA Ping ZHANG Denghui wang songyan CHAO Tao Control and Simulation Center Harbin Institute of Technology

A composited integrated guidance and control(IGC) algorithm is presented to tackle the problem of the IGC design in the dive phase for the bank-to-turn(BTT) vehicle with the inaccuracy information of the line-of-sight(LOS) rate. For the sake of theoretical derivation, an IGC model in the pitch plane is established. The high-order finite-time state observer(FTSO), with the LOS angle as the single input, is employed to reconstruct the states of the system online. Besides, a composited IGC algorithm is presented via the fusion of back-stepping and dynamic inverse. Compared with the traditional IGC algorithm, the proposed composited IGC method can attenuate effectively the design conservation of the flight control system, while the LOS rate is mixed with noise. Extensive experiments have been performed to demonstrate that the proposed approach is globally finite-time stable and strongly robust against parameter uncertainty.

关键词： integrated guidance and control(IGC) finite-time state observer(FTSO) back-to-turn(BTT) vehicle composited control

Analysis of the parathyroid function in maintenance hemodialysis patients from Changchun, China

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Chronic Diseases and Translational Medicine 2017年第3期3卷 181-185页

作者： Juan Du Songyan WANG wangbo Yu Shuang Li Jingbo Xu Department of Endocrinology Jilin Province People's Hospital Changchun 130021 China Department of Nephrology Jilin Province People's Hospital Changchun 130021 China Department of Health Care Changchun Central Hospital Changchun 130021 China Center of Hemodialysis Changchun Nanguan District Hospital Changchun 130021 China

Objective: To evaluate the parathyroid function in maintenance hemodialysis patients from 4 hemodialysis centers and to analyze the cause of the dysfunction. Methods: This cross-sectional study included patients with chronic renal disease undergoing maintenance hemodialysis treatment at 4 hemodialysis centers in Changchun, China, between March 2014 and August 2015. A total of 337 patients were asked to complete a questionnaire including their name, gender, age, hemodialysis duration, the use of calcium carbonate and vitamin D3 supplements, health education status, hemofiltration frequency, appetite, and education level. Serum intact parathyroid hormone (iPTH), phosphorus, total calcium, blood urea nitrogen (BUN), and creatinine (Cre) levels were obtained from clinical information. Patients with iPTH data were divided into 2 groups: Normal group: the patients with an iPTH level 100 pg/ml (136 subjects). Intergroup differences were analyzed using the t -test. The enumeration data were analyzed by the χ 2 test. Results: The iPTH levels were not monitored for 173 maintenance hemodialysis patients (51.3%) but for 164 patients (48.7%). Of the 164 patients, 28 (17.1%) had a normal serum iPTH level, while the other 136 (82.9%) had an abnormal iPTH level. The maintenance hemodialysis duration and phosphorus levels in the Abnormal group were higher than those in the Normal group ( P < 0.05). The appetites of patients in the Abnormal group were better than those of patients in the Normal group ( P < 0.05). Conclusions: A lower proportion of patients on hemodialysis had a normal iPTH level. The phosphorus levels of patients on hemodialysis should be controlled via dietary interventions.

关键词： Maintenance hemodialysis Intact parathyroid hormone Serum phosphorus

Research on Credibility Evaluation for Radio Frequency Guided Hardware-In-the-Loop Simulation System

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Research on Credibility Evaluation for Radio Frequency Guide...

Reprocessing 12-yr Microwave Humidity Sounder Historical Data of Fengyun-3 Satellites

第36届中国控制会议

作者： Yuxiao wang Tao Chao Chaolei wang Songyan WANG Harbin Institute of Technology Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

ISBN: (纸本)9781538629185

To ensure the effectiveness of the RF（Radio Frequency） guided HILS（Hardware-In-the-Loop Simulation） system,the credibility evaluation was necessary.At present,most of the methods were applied in the case of the simulation system input being consistent with the real system input,which is difficult to achieve in some subsystem of the RF guided HILS system.In this paper,the relative complete system reliability evaluation index system was established.Subsystems were classified,for different categories of subsystem,corresponding reliability assessment methods were studied.In particular,reliability evaluation methods based on performance level were put forward,when certain subsystems cannot be evaluated by consistency analysis methods.A simple example was given to show the evaluation process.

关键词： Radio Frequency Guided Hardware-In-the-Loop Simulation Credibility Evaluation Index System Performance Index

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Journal of Meteorological Research 2022年第2期36卷 261-270页

作者： Yang GUO Fangli DOU Qiong WU Jieying HE Shengwei ZHANG Zhenzhan wang songyan GU Peng ZHANG Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081 Innovation Center for Fengyun Meteorological Satellite(FYSIC) China Meteorological AdministrationBeijing 100081 National Space Science Center Chinese Academy of SciencesBeijing 100190

Atmospheric water vapor is an essential climate variable(ECV)with extensive spatial and temporal variations.Microwave humidity observations from meteorological satellites provide important information for climate system variables,including atmospheric water vapor and precipitable water,and assimilation in numerical weather prediction(NWP)and reanalysis.As one of the payloads onboard China’s second-generation polar-orbiting operational meteorological Fengyun-3(FY-3)satellites,the Microwave Humidity Sounder(MWHS)has been continuously observing the global humidity since 2008.The reprocessing of historical FY-3 MWHS data is documented in detail in this study.After calibrating and correcting the data,the quality of the reprocessed dataset is evaluated and the improvement is shown in this study.The results suggest that MWHS observations bias is reduced to approximately 0.8 K,compared with METOP-A Microwave Humidity Sounder(MHS).The temporal variability of MWHS is highly correlated with the instrument temperature.After reprocessing,the scene temperature dependency is mitigated for all 183 GHz channels,and the consistency and stability between FY-3A/B/C are also improved.

关键词： Fengyun-3 Microwave Humidity Sounder historical data reprocessing

Implications of Stahl's Theorems to Holomorphic Embedding Part II: Numerical Convergence

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CSEE Journal of Power and Energy Systems 2021年第4期7卷 773-784页

作者： Abhinav Dronamraju songyan Li Qirui Li Yuting Li Daniel Tylavsky Di Shi Zhiwei wang School of Electrical Computer and Energy Engineering in Arizona State University TempeAZ 85287USA Southwest Electric Power Design Institute Co. Ltd.of China Siemens 8850 Fallbrook Dr.HoustonTexas 77064United States AINERGY LLC Santa ClaraCA 95051 State Grid Jiangsu Electric Power Company Nanjing 210024China

What has become known as Stahl's Theorem in power-engineering circles has been used to justify a convergence guarantee of the Holomorphic Embedding Method(HEM)as it applies to the power-flow problem.In this,the second part of a two-part paper,we examine implications to numerical convergence of the HEM and the numerical properties of a Pade approximant algorithm.We show that even if the point of interest is within the convergence domain,numerical convergence of the sequence of Pade approximants computed with finite precision is not guaranteed.We propose a convergence factor equation that can be used to both estimate the convergence rate and the capacity of the branch cut.We also show that the study of convergence properties of the Pade approximant is the study of the location of the branch-points of the function,which in turn dictate branch-cut topology and capacity and,therefore,convergence rate.

关键词： Analytic continuation HEM holomorphic embedding method power flow Pade approximants StahPs theorems