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Dynamics modeling and motion control for high-speed underwater vehicles using H-infinity synthesis with anti-windup compensator

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Journal of Ocean Engineering and Science 2022年第1期7卷 84-91页

作者： Phuc Duc Hong Bui sam-sang you Hwan-Seong Kim sang-Do Lee Department of Mechanical Engineering The University of TulsaTulsaOK 74104United States Division of Mechanical Engineering Korea Maritime and Ocean UniversityBusan 49112Republic of Korea Division of Logistics Engineering Korea Maritime and Ocean UniversityBusan 49112Republic of Korea Division of Navigation and Information System Mokpo National Maritime UniversityMokpoJeollanam-do 58628Republic of Korea

The control synthesis of a high-speed supercavitating vehicle(HSSV)faces many difficulties such as the stability,control,and maneuvering with dynamical uncertainties due to parameter perturbations,exter-nal disturbances,unmodeled dynamics,measurement noises,and actuator *** by the HSSV dynamical analysis,this paper proposes the H∞(i.e."H-infinity")robust control synthesis to gen-erate a robust low-order controller,which is intended for real implementations to ensure active control ***,the presented control scheme includes a feedback component and an anti-windup *** anti-windup synthesis is to provide system stability under actuator ***-tensive simulations show that the designed controller provides good performances with high robustness for vertical plane manoeuver while effectively eliminating planning forces,exogenous disturbances and noises as well as overcoming cavitator saturations.

关键词： Vehicle dynamics Planing force Vertical maneuver H-infinity control Anti-windup Actuator saturation

Autopilot Control Synthesis for Path Tracking Maneuvers of Underwater Vehicles

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China Ocean Engineering 2011年第2期25卷 237-249页

作者： sam-sang you Hyeung-Sik CHOI Hwan-Seong KIM Han-Il PARK School of Mechanical and Energy Systems Engineering Korea Maritime University Department of Logistics System Engineering Korea Maritime University Department of Ocean Engineering Korea Maritime University

This paper is concerned with the robust control synthesis of autonomous underwater vehicle （AUV） for general path following maneuvers. First, we present maneuvering kinematics and vehicle dynamics in a unified framework. Based on H∞ loop-shaping procedure, the 2-DOF autopilot controller has been presented to enhance stability and path tracking. By use of model reduction, the high-order control system is reduced to one with reasonable order, and further the scaled low-order controller has been analyzed in both the frequency and the time domains. Finally, it is shown that the autopilot control system provides robust performance and stability against prescribed levels of uncertainty.

关键词： underwater vehicle path following 2-DOF control synthesis H∞ loop-shaping plant uncertainty model reduction

Observed-based decision-making strategy of supply chain management under business disruptions

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Journal of Control and Decision 2023年第4期10卷 504-513页

作者： Xiao Xu Truong Ngoc Cuong Hwan-Seong Kim sam-sang you Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China Division of Logistics Korea Maritime and Ocean UniversityBusanRepublic of Korea Division of Mechanical Engineering Korea Maritime and Ocean UniversityBusanRepublic of Korea

This paper presents observer-based chaos suppression for a four-echelon supply chain system based on fractional order *** the market information is usually distorted,nonlinear observers for supply chain model are implemented to accomplish chaos suppression using linear matrix inequality(L MI).Sufficient conditions for the observer-based schemes are estab-lished by using Lyapunov stbility *** fractional calculus is utilised to provide superior dynamic performance for the controlled supply chain system over its integer-order *** simulations are performed to validate robust performance and stability of observer-based supply chain ***,it is found that the presented approach can help decision-makers develop effective supply chain networks under disruptions.

关键词： Supply chain system decision making fractional order calculus state observer chaos suppression linear matrix inequality

Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction

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Carbon Energy 2024年第4期6卷 79-90页

作者： Kyung‐Jong Noh Byoung Joon Park Ying Wang Yejung Choi sang‐Hoon you Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)PohangGyeongbukRepublic of Korea Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)PohangGyeongbukRepublic of Korea Pohang Accelerator Laboratory(PAL) Beamline DivisionPohangGyeongbukRepublic of Korea

Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction ***,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains ***,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal ***‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus *** studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH *** research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions.

关键词： atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst

Sparse Reconstructive Evidential Clustering for Multi-View Data

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 459-473页

作者： Chaoyu Gong Yang you School of Computing National University of SingaporeSingapore

Although many multi-view clustering(MVC) algorithms with acceptable performances have been presented, to the best of our knowledge, nearly all of them need to be fed with the correct number of clusters. In addition, these existing algorithms create only the hard and fuzzy partitions for multi-view objects,which are often located in highly-overlapping areas of multi-view feature space. The adoption of hard and fuzzy partition ignores the ambiguity and uncertainty in the assignment of objects, likely leading to performance degradation. To address these issues, we propose a novel sparse reconstructive multi-view evidential clustering algorithm(SRMVEC). Based on a sparse reconstructive procedure, SRMVEC learns a shared affinity matrix across views, and maps multi-view objects to a 2-dimensional humanreadable chart by calculating 2 newly defined mathematical metrics for each object. From this chart, users can detect the number of clusters and select several objects existing in the dataset as cluster centers. Then, SRMVEC derives a credal partition under the framework of evidence theory, improving the fault tolerance of clustering. Ablation studies show the benefits of adopting the sparse reconstructive procedure and evidence theory. Besides,SRMVEC delivers effectiveness on benchmark datasets by outperforming some state-of-the-art methods.

关键词： Evidence theory multi-view clustering(MVC) optimization sparse reconstruction

Non-Deterministic Liveness-Enforcing Supervisor Tolerant to Sensor-Reading Modification Attacks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 240-248页

作者： Dan you Shouguang Wang IEEE the School of Information and Electronic Engineering Sussex Artificial Intelligence InstituteZhejiang Gongshang UniversityHangzhou 310018China

In this paper, we study the supervisory control problem of discrete event systems assuming that cyber-attacks might occur. In particular, we focus on the problem of liveness enforcement and consider a sensor-reading modification attack(SM-attack) that may disguise the occurrence of an event as that of another event by intruding sensor communication channels. To solve the problem, we introduce non-deterministic supervisors in the paper, which associate to every observed sequence a set of possible control actions offline and choose a control action from the set randomly online to control the system. Specifically, given a bounded Petri net(PN) as the reference formalism and an SMattack, an algorithm that synthesizes a liveness-enforcing nondeterministic supervisor tolerant to the SM-attack is proposed for the first time.

关键词： Cyber-attacks cyber-physical system(CPS) liveness non-deterministic supervisors Petri net(PN)

Theoretical study on the synergistic mechanism of Fe–Mn in sodium-ion batteries

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Particuology 2024年第10期93卷 284-290页

作者： Yang you Mingliang Yuan School of Mineral Processing and Bioengineering Central South UniversityChangsha410083China

This article conducts first-principles calculations to initially explore the construction of two configurations,NaFeO_(2)(NFO)and NaMnO_(2)(NMO),and studies the mixing enthalpies under different Fe–Mn *** results indicate that NaFe3/8Mn5/8O_(2)(NFMO)exhibits the most thermodynamically stable *** calculations on the mixing enthalpies and volume changes during the sodium extraction process for NFO,NMO,and NFMO configurations are presented,along with the partial density of states(PDOS)and Bader charges of transition metals(TM)and *** calculations reveal the synergistic mechanism of Fe and *** and Mn can engage in more complex electron exchanges during sodium extraction,optimizing the internal electron density distribution and overall charge balance,thereby stabilizing the crystal structure and reducing the migration of Fe^(3+)to the sodium layers during deep sodium *** interaction between Fe’s 3d electrons and Mn’s 3d electrons through the shared oxygen atoms’2p orbitals occurs in the Fe–Mn–O *** interaction can lead to a rebalancing of the electron density around Mn³⁺atoms,mitigating the asymmetric electron density distribution caused by the d4 configuration of the lone Mn³⁺and suppressing the Jahn-Teller effect of Mn^(3+).Moreover,the synergistic effects between Fe and Mn can provide a more balanced charge distribution,reducing extreme changes to the charge state of oxygen atoms and decreasing the irreversible oxygen release caused by anionic redox reactions during deep sodium extraction,thereby enhancing the material’s *** in-depth study of the interaction mechanism at the microscopic level when co-doping Fe and Mn offers valuable insights for the rational design and development of high-performance cathode materials.

关键词： First-principles calculations Sodium-ionbatteries Layered oxides NaFe_(3/8)Mn_(3/8)O_(2)

Shaping the Spatial Coherence of Quantum Source

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Chinese Physics Letters 2024年第9期41卷 38-39页

作者： Chenglong you Quantum Photonics Laboratory Department of Physics and AstronomyLouisiana State UniversityBaton RougeLouisiana 70803USA

There has been immense research interest in quantum entanglement due to its ability to generate stronger-thanclassical nonlocal correlations.^([1,2])These strong,nonlocal correlations form the backbone of various quantum information *** of the core principles of quantum entanglement is quantum coherence,which provides deep insights into the statistical correlations among quantum particles.^([3–5])Quantum coherence reflects the wavelike properties of quantum particles,enabling them to exhibit interference and unique quantum behaviors.

关键词： particles. quantum backbone

Chemical and mechanical properties of stainless, environment-friendly, and nonflammable Mg alloys (SEN alloys): A review

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Journal of Magnesium and Alloys 2024年第3期12卷 841-872页

作者： Jong Un Lee Hyun Ji Kim sang-Cheol Jin Ye Jin Kim young Min Kim Bong Sun you Jun Ho Bae Sung Hyuk Park Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Missile Research Institute Agency for Defense DevelopmentDaejeon 34060Republic of Korea

This review article provides overall understanding of stainless,environment-friendly,and nonflammable Mg alloys(SEN alloys)recently developed at the Korea Institute of Materials *** alloys are produced by adding small amounts of Ca and Y(each<1 wt%)into commercial Mg–Al based alloys,resulting in exceptional ignition and corrosion resistances and impressive mechanical *** main advantages of SEN alloys are as follows.(1)A dense multi-oxide layer of SEN alloys comprising MgO,CaO,and Y_(2)O_(3) impedes the outward dispersion of Mg vapor and the inward penetration of O_(2) during oxidation,thereby enhancing the oxidation and ignition resistances.(2)The presence of Ca-and Y-based second-phase particles in SEN alloys can enhance their corrosion resistance because Ca-containing particles prevent the spread of corrosion,and the replacement of Al-containing particles with less noble ones containing Y(e.g.,Al–Mn–Y or Al–Y particles)retards corrosion.(3)The addition of minor amounts of Ca and Y renders excellent mechanical properties due to improved strengthening *** enhanced properties are attributed to more pronounced dynamic recrystallization and grain refining behaviors caused by the second-phase particles during extrusion.(4)Despite the presence of various types of second-phase particles,the fatigue properties of SEN9 alloys are similar to those of commercial AZ91 alloys.(5)Simultaneous introduction of Ca and Y suppresses the formation of Mg17Al12 discontinuous precipitates during aging,leading to the enhanced elongation of aged SEN alloys.(6)Adding mischmetal into the SEN9 alloy leads to a six-fold enhancement in ***,the studies conducted on SEN alloys demonstrate their excellent ignition and corrosion resistances and mechanical properties,which broaden the industrial applications of Mg alloys by addressing their inherent weaknesses.

关键词： SEN magnesium alloy Corrosion resistance Ignition resistance Mechanical properties Extrudability.