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Dynamic Event-Triggered Consensus Control for Input Constrained Multi-Agent Systems With a Designable Minimum Inter-Event Time
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作者 Meilin Li Yue Long +2 位作者 Tieshan Li Hongjing Liang C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期649-660,共12页
This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynami... This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach. 展开更多
关键词 Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control
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Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
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作者 Lu Li Zeduan Zhang +5 位作者 Wang Cai Qikang Zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan 《Global Energy Interconnection》 EI CSCD 2024年第2期206-216,共11页
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti... This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances. 展开更多
关键词 Through-type Cophase traction direct power supply system Traction network Empirical wavelet transform(EWT) Longitudinal protection
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Radial solution of the Logarithmic Laplacian system
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作者 ZHANG Li-hong NIE Xiao-feng +1 位作者 WANG Guo-tao Bashir Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期114-124,共11页
The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the ... The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the radial symmetry of the solution of the Logarithmic Laplacian system is obtained. 展开更多
关键词 the Logarithmic Laplacian system radial symmetry the direct method of moving planes
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Community Perception of Riparian Corridors Ecosystem Services and Implications for Environmental Education in Upper Oueme Catchment in Benin, West Africa
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作者 Socrate Mercator Dossou Kinnoumè Serge Adomou +1 位作者 Gérard Nounagnon Gouwakinnou Thierry Dèhouégnon Houéhanou 《Open Journal of Ecology》 2024年第2期125-147,共23页
The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the per... The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors. 展开更多
关键词 Local Knowledge Direct Use Value Soil Formation Migration Importance Value BENIN
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Robust Consensus Tracking Control of Uncertain Multi-Agent Systems With Local Disturbance Rejection 被引量:1
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作者 Pan Yu Kang-Zhi Liu +3 位作者 Xudong Liu Xiaoli Li Min Wu Jinhua She 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期427-438,共12页
In this paper,a new distributed consensus tracking protocol incorporating local disturbance rejection is devised for a multi-agent system with heterogeneous dynamic uncertainties and disturbances over a directed graph... In this paper,a new distributed consensus tracking protocol incorporating local disturbance rejection is devised for a multi-agent system with heterogeneous dynamic uncertainties and disturbances over a directed graph.It is of two-degree-of-freedom nature.Specifically,a robust distributed controller is designed for consensus tracking,while a local disturbance estimator is designed for each agent without requiring the input channel information of disturbances.The condition for asymptotic disturbance rejection is derived.Moreover,even when the disturbance model is not exactly known,the developed method also provides good disturbance-rejection performance.Then,a robust stabilization condition with less conservativeness is derived for the whole multi-agent system.Further,a design algorithm is given.Finally,comparisons with the conventional one-degree-of-freedombased distributed disturbance-rejection method for mismatched disturbances and the distributed extended-state observer for matched disturbances validate the developed method. 展开更多
关键词 Directed graph distributed control disturbance rejection dynamic uncertainties multi-agent systems robust control
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Practical prescribed-time tracking control for uncertain strict-feedback systems with guaranteed performance under unknown control directions 被引量:1
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作者 Zhou Yang Yujuan Wang Frank L.Lewis 《Journal of Automation and Intelligence》 2023年第2期99-104,共6页
In this paper,we consider the practical prescribed-time performance guaranteed tracking control problem for a class of uncertain strict-feedback systems subject to unknown control direction.Due to the existence of unk... In this paper,we consider the practical prescribed-time performance guaranteed tracking control problem for a class of uncertain strict-feedback systems subject to unknown control direction.Due to the existence of unknown nonlinearities and uncertainties,it is challenging to design a controller that can ensure the stability of closed-loop system within a predetermined finite time while maintaining the specified transient performance.The underlying problem becomes further complex as the control directions are unknown.To deal with the above problems,a special translation function as well as Nussbaum type function are introduced in the prescribed performance control(PPC)framework.Finally,a PPC as well as preset finite time tracking control scheme is designed,and its effectiveness is confirmed by both theoretical analysis and numerical simulation. 展开更多
关键词 Strict-feedback systems Practical prescribed-time control Prescribed performance control Unknown control direction
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How Generative Adversarial Networks Promote the Development of Intelligent Transportation Systems:A Survey
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作者 Hongyi Lin Yang Liu +1 位作者 Shen Li Xiaobo Qu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第9期1781-1796,共16页
In current years,the improvement of deep learning has brought about tremendous changes:As a type of unsupervised deep learning algorithm,generative adversarial networks(GANs)have been widely employed in various fields... In current years,the improvement of deep learning has brought about tremendous changes:As a type of unsupervised deep learning algorithm,generative adversarial networks(GANs)have been widely employed in various fields including transportation.This paper reviews the development of GANs and their applications in the transportation domain.Specifically,many adopted GAN variants for autonomous driving are classified and demonstrated according to data generation,video trajectory prediction,and security of detection.To introduce GANs to traffic research,this review summarizes the related techniques for spatio-temporal,sparse data completion,and time-series data evaluation.GAN-based traffic anomaly inspections such as infrastructure detection and status monitoring are also assessed.Moreover,to promote further development of GANs in intelligent transportation systems(ITSs),challenges and noteworthy research directions on this topic are provided.In general,this survey summarizes 130 GAN-related references and provides comprehensive knowledge for scholars who desire to adopt GANs in their scientific works,especially transportation-related tasks. 展开更多
关键词 driving TRANSPORTATION DIRECTIONS
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The Impact of Sun Radiation on the Thermal Comfort in Highly Glazed Buildings Equipped with Floor Heating Systems
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作者 Abdelatif Merabtine Abdelhamid Kheiri +1 位作者 Salim Mokraoui Lyes Bellagh 《Fluid Dynamics & Materials Processing》 EI 2023年第4期941-951,共11页
Occupants of highly glazed buildings often suffer from thermal discomfort during the mid-seasons when no shadings are used in such buildings,especially when inertial heating systems are used.The present study is devot... Occupants of highly glazed buildings often suffer from thermal discomfort during the mid-seasons when no shadings are used in such buildings,especially when inertial heating systems are used.The present study is devoted to evaluating the impact of long solar beam exposure on the internal thermal discomfort in glazed spaces when heating is implemented through a floor system.A comprehensive experimental study is carried out using an experimental bi-climatic chamber which is fully monitored and controlled,allowing realistic simulations of the dynamic movement of the sun patch on a heated slab.The findings show that a period of discomfort as long as 8 h can occur,and persist far after the sunbeam exposure stops.During this period,the heating slab’s surface temperature,considered from an average point of view,can attain 34°C while the indoor temperature reaches 26°C.Simulations conducted using a previously developed model display a good fit with the measurements. 展开更多
关键词 Radiant system direct solar radiation thermal performance glazed spaces thermal discomfort
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Minimizing FWM Impact in DWDM ROF DP-DQPSK System for Optical
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作者 Esra Ehsan Razali Ngah Nurul Ashikin Binti Daud 《Computers, Materials & Continua》 SCIE EI 2023年第4期1033-1050,共18页
The demonstration of a higher data rate transmission system was amajor aspect to be considered by researchers in recent years. The most relevantaspect to be studied and analyzed is the need for a reliable system to ha... The demonstration of a higher data rate transmission system was amajor aspect to be considered by researchers in recent years. The most relevantaspect to be studied and analyzed is the need for a reliable system to handlenonlinear impairments and reduce them. Therefore, this paper examines theinfluence of Four-Wave Mixing (FWM) impairment on the proposed highdata rate Dual polarization–Differential Quadrature phase shift keying (DPDQPSK)system using the Optisystem software. In the beginning, the impactof varied input power on the proposed system’s performance was evaluated interms of QF and BER metrics. More power is used to improve system performance.However, increasing power would raise theFWMeffects. Accordingly,a−10dBminput power and the proposed system are used to reduce the impactof FWM. Additionally, a hybrid amplification method is proposed to enhancesystem performance by utilizing the major amplification methods of erbiumdopedfiber amplifier (EDFA): semiconductor optical amplifier (SOA) andRadio optical amplifier (ROA). The evaluation demonstrates that the OAEDFAoutperformed the other two key amplification techniques of (EDFASOA)and (EDFA-ROA) in improving Quality factor (QF) and Bit error rate(BER) system results for all distances up to 720 km. Consequently, the methodcontributes to minimizing the impact of FWM. In the future, other forms ofnonlinearity will be investigated and studied to quantify their impact on theproposed system. 展开更多
关键词 Direct detection DQPSK bit error rate quality factor Dense wavelength division multiplexing(DWDM)
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A systematic printability study of direct ink writing towards high-resolution rapid manufacturing
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作者 Qingyang Zheng Bin Xie +1 位作者 Zhoulong Xu Hao Wu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期500-517,共18页
Direct ink writing(DIW)holds enormous potential in fabricating multiscale and multi-functional architectures by virtue of its wide range of printable materials,simple operation,and ease of rapid prototyping.Although i... Direct ink writing(DIW)holds enormous potential in fabricating multiscale and multi-functional architectures by virtue of its wide range of printable materials,simple operation,and ease of rapid prototyping.Although it is well known that ink rheology and processing parameters have a direct impact on the resolution and shape of the printed objects,the underlying mechanisms of these key factors on the printability and quality of DIW technique remain poorly understood.To tackle this issue,we systematically analyzed the printability and quality through extrusion mechanism modeling and experimental validating.Hybrid non-Newtonian fluid inks were first prepared,and their rheological properties were measured.Then,finite element analysis of the whole DIW process was conducted to reveal the flow dynamics of these inks.The obtained optimal process parameters(ink rheology,applied pressure,printing speed,etc)were also validated by experiments where high-resolution(<100μm)patterns were fabricated rapidly(>70 mm s^(-1)).Finally,as a process research demonstration,we printed a series of microstructures and circuit systems with hybrid inks and silver inks,showing the suitability of the printable process parameters.This study provides a strong quantitative illustration of the use of DIW for the high-speed preparation of high-resolution,high-precision samples. 展开更多
关键词 direct ink writing extrusion mechanism modelling computational fluid dynamic(CFD) printability process parameters high-resolution printing
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Nonlinear direct data-driven control for UAV formation flight system
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作者 WANG Jianhong Ricardo A.RAMIREZ-MENDOZA XU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1409-1418,共10页
This paper proposes the nonlinear direct data-driven control from theoretical analysis and practical engineering,i.e.,unmanned aerial vehicle(UAV)formation flight system.Firstly,from the theoretical point of view,cons... This paper proposes the nonlinear direct data-driven control from theoretical analysis and practical engineering,i.e.,unmanned aerial vehicle(UAV)formation flight system.Firstly,from the theoretical point of view,consider one nonlinear closedloop system with a nonlinear plant and nonlinear feed-forward controller simultaneously.To avoid the complex identification process for that nonlinear plant,a nonlinear direct data-driven control strategy is proposed to design that nonlinear feed-forward controller only through the input-output measured data sequence directly,whose detailed explicit forms are model inverse method and approximated analysis method.Secondly,from the practical point of view,after reviewing the UAV formation flight system,nonlinear direct data-driven control is applied in designing the formation controller,so that the followers can track the leader’s desired trajectory during one small time instant only through solving one data fitting problem.Since most natural phenomena have nonlinear properties,the direct method must be the better one.Corresponding system identification and control algorithms are required to be proposed for those nonlinear systems,and the direct nonlinear controller design is the purpose of this paper. 展开更多
关键词 nonlinear system nonlinear direct data-driven control model inverse control unmanned aerial vehicle(UAV)formation flight.
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Hybrid Optimization Based PID Controller Design for Unstable System
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作者 Saranya Rajeshwaran C.Agees Kumar Kanthaswamy Ganapathy 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1611-1625,共15页
PID controllers play an important function in determining tuning para-meters in any process sector to deliver optimal and resilient performance for non-linear,stable and unstable processes.The effectiveness of the pre... PID controllers play an important function in determining tuning para-meters in any process sector to deliver optimal and resilient performance for non-linear,stable and unstable processes.The effectiveness of the presented hybrid metaheuristic algorithms for a class of time-delayed unstable systems is described in this study when applicable to the problems of PID controller and Smith PID controller.The Direct Multi Search(DMS)algorithm is utilised in this research to combine the local search ability of global heuristic algorithms to tune a PID controller for a time-delayed unstable process model.A Metaheuristics Algorithm such as,SA(Simulated Annealing),MBBO(Modified Biogeography Based Opti-mization),BBO(Biogeography Based Optimization),PBIL(Population Based Incremental Learning),ES(Evolution Strategy),StudGA(Stud Genetic Algo-rithms),PSO(Particle Swarm Optimization),StudGA(Stud Genetic Algorithms),ES(Evolution Strategy),PSO(Particle Swarm Optimization)and ACO(Ant Col-ony Optimization)are used to tune the PID controller and Smith predictor design.The effectiveness of the suggested algorithms DMS-SA,DMS-BBO,DMS-MBBO,DMS-PBIL,DMS-StudGA,DMS-ES,DMS-ACO,and DMS-PSO for a class of dead-time structures employing PID controller and Smith predictor design controllers is illustrated using unit step set point response.When compared to other optimizations,the suggested hybrid metaheuristics approach improves the time response analysis when extended to the problem of smith predictor and PID controller designed tuning. 展开更多
关键词 Direct multi search simulated annealing biogeography-based optimization stud genetic algorithms particle swarm optimization SmithPID controller
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Open banking and inclusive finance in the European Union:perspectives from the Dutch stakeholder ecosystem
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作者 Massimo Preziuso Franziska Koefer Michel Ehrenhard 《Financial Innovation》 2023年第1期2752-2778,共27页
In the European Union(EU),the revised Payment Services Directive(PSD2)aims to provide more convenient and customized financial products through open banking(OB)platforms.However,little attention has been paid to the r... In the European Union(EU),the revised Payment Services Directive(PSD2)aims to provide more convenient and customized financial products through open banking(OB)platforms.However,little attention has been paid to the role of OB in improving the financial well-being of the growing number of the EU’s underserved groups,which currently constitute approximately a quarter of its population.This study examines how the PSD2 and OB impact inclusive finance in the EU based on the perspectives of the Netherlands’ecosystem,one of the leaders in the EU’s financial technology(FinTech)landscape.A fundamental distinction can be drawn between the OB users and the ecosystem’s players.Regarding the impact of financial services on the users’inclusivity,while the PSD2 strengthens the infrastructure necessary for financial inclusion,many challenges remain,mainly because it was not designed for this purpose.This study identifies several areas of improvement that include adjustments to the know your customer and anti-money laundering processes for underserved customers,innovative ways to communicate the PSD2’s potential,and the regulation of technology providers’activities to build trust.Meanwhile,from the ecosystem’s position,there is a need to strengthen and improve microfinance regulation according to the opportunities provided by the PSD2 to support microfinance institutions(MFIs)in scaling up and reaching underserved clients across borders with innovative services.OB improvements can also be achieved by organizations formed by MFIs and FinTechs in collaboration with banks.Such hybrid institutions will combine the best features of each of them:knowledge of the needs of local underserved clients from MFIs,technological innovations from FinTechs,and large and trusted customer bases,infrastructures,and access to institutional investments and governments from banks.Finally,an EU inclusive OB sector depends on the centrality of trusted regulators as coordination bodies.The PSD2 requires adjustments for underserved populations’specific needs.OB improvements can be achieved by organizations formed by MFIs and Fin-Techs in collaboration with banks.Regulated technical service providers(TSPs)are crucial to building trust and customer adoption in OB.The European Banking Authority(EBA)may function as coordination body to design inclusive rules by engaging with OB stakeholders.As inclusive finance moves into open-finance and data eras,an increasing regulatory complexity and scope will require networks of innovative and trusted regulators. 展开更多
关键词 The Revised Payment Services Directive(PSD2) Open banking Inclusive finance ECOsystemS FinTech The Netherlands The European Union
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Rooted Tree Optimization for Wind Turbine Optimum Control Based on Energy Storage System
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作者 Billel Meghni Afaf Benamor +7 位作者 Oussama Hachana Ahmad Taher Azar Amira Boulmaiz Salah Saad El-Sayed M.El-kenawy Nashwa Ahmad Kamal Suliman Mohamed Fati Naglaa K.Bahgaat 《Computers, Materials & Continua》 SCIE EI 2023年第2期3977-3996,共20页
The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical networks.Therefore,in order to avoid this issue,WTs hybridization with a storage syst... The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical networks.Therefore,in order to avoid this issue,WTs hybridization with a storage system is a mandatory.This paper investigates WT system operating at variable speed.The system contains of a permanent magnet synchronous generator(PMSG)supported by a battery storage system(BSS).To enhance the quality of active and reactive power injected into the network,direct power control(DPC)scheme utilizing space-vector modulation(SVM)technique based on proportional-integral(PI)control is proposed.Meanwhile,to improve the rendition of this method(DPC-SVM-PI),the rooted tree optimization technique(RTO)algorithm-based controller parameter identification is used to achieve PI optimal gains.To compare the performance ofRTO-based controllers,they were implemented and tested along with some other popular controllers under different working conditions.The obtained results have shown the supremacy of the suggested PIRTO algorithm compared to competing controllers regarding total harmonic distortion(THD),overshoot percentage,settling time,rise time,average active power value,overall efficiency,and active power steadystate error. 展开更多
关键词 Rooted tree optimization(RTO)method direct power control(DPC) wind turbine(WT) proportional integral(PI) PMSG
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Systemic right ventricle complications in levo-transposition of the great arteries: A case report and review of literature
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作者 Mohamed Ramzi Almajed Abdulla Almajed +2 位作者 Naoshin Khan Mark S Obri Karthikeyan Ananthasubramaniam 《World Journal of Cardiology》 2023年第10期542-552,共11页
BACKGROUND Congenitally corrected levo-transposition of the great arteries(L-TGA)is a congenital heart disease in which the ventricles and great arteries are transposed from their typical anatomy.In L-TGA,the double d... BACKGROUND Congenitally corrected levo-transposition of the great arteries(L-TGA)is a congenital heart disease in which the ventricles and great arteries are transposed from their typical anatomy.In L-TGA,the double discordance,atrioventricular and ventriculoarterial,create an acyanotic milieu which allows patients to survive their early decades,however,progressive systemic right ventricle(sRV)dys-function creates complications later in life.sRV dysfunction and remodeling predisposes patients to intracardiac thrombus(ICT)formation.CASE SUMMARY A 40-year-old male with L-TGA presented with symptoms of acute decom-pensated heart failure.In childhood,he had surgical repair of a ventricular septal defect.In adulthood,he developed sRV dysfunction,systemic tricuspid valve(sTV)regurgitation,and left-bundle branch block for which he underwent cardiac resynchronization therapy.Transthoracic echocardiogram showed a sRV ejection fraction of 40%,severe sTV regurgitation,and a newly identified sRV ICT.ICT was confirmed by ultrasound-enhancing agents and transesophageal echocardio-graphy.Our patient was optimized with guideline-directed medical therapy and diuresis.Anticoagulation was achieved with a vitamin K antagonist(VKA)and he was later referred for evaluation by advanced heart failure and heart transplant services.CONCLUSION Anticoagulation with VKA is the mainstay of treatment in the absence of conclusive data supporting direct oral anticoagulant use in ICT in patients with congenital heart disease.This case illustrates the natural history of L-TGA and highlights the importance of surveillance and monitoring with dedicated cardiac imaging to identify complications. 展开更多
关键词 Levo-transposition of the great arteries systemic right ventricle Congenital heart disease Intracardiac thrombus ANTICOAGULATION Direct oral anticoagulant Case report
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Design and Implementation of Smart Power Voltage and Frequency Synchroniser in Power Distribution System
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作者 Isaac Kofi Mensah Prah Joseph Cudjoe Attachie 《Journal of Power and Energy Engineering》 2023年第4期1-16,共16页
Voltage and frequency are usually considered and assessed independently in the design and operation of electrical networks. However, these two are linked. Each and every malfunctioning electrical system has an impact ... Voltage and frequency are usually considered and assessed independently in the design and operation of electrical networks. However, these two are linked. Each and every malfunctioning electrical system has an impact on both voltage and frequency. This paper presents the opportunity for monitoring the distributed electrical energy by means of a system that monitors, controls, and provides a breakpoint based on high or low voltage and frequency tripping mechanism that avoids any damage to the load. The designed system comprised a switch mode power supply (SMPS), a direct digital synthesizer (DDS), and PIC16F876A microcontroller techniques for stable voltage and frequency outputs. Proteus design suite version 8.11 software and Benchcope SDS1102CN were used for modeling and simulation. The hardware prototype was implemented at a telecom cell site for data capturing and analysis. Test results showed that the implementation of the prototype provided stable and constant outputs of 222 V/50 Hz and 112 V/60 Hz which constituted 99% and 99.8% efficiency for voltage and frequency performance respectively. The paper also discusses different technologies that can be adopted by the system to mitigate voltage and frequency effects on customer appliances. 展开更多
关键词 Switch Mode Power Supply Direct Digital Synthesis Pulse Width Modulation H-Bridge Mosfet MICROCONTROLLER FILTERING and Rectification
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Linear System Solutions of the Navier-Stokes Equations with Application to Flow over a Backward-Facing Step
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作者 Achraf Badahmane 《Open Journal of Fluid Dynamics》 2023年第3期133-143,共11页
Many applications in fluid mechanics require the numerical solution of sequences of linear systems typically issued from finite element discretization of the Navier-Stokes equations. The resulting matrices then exhibi... Many applications in fluid mechanics require the numerical solution of sequences of linear systems typically issued from finite element discretization of the Navier-Stokes equations. The resulting matrices then exhibit a saddle point structure. To achieve this task, a Newton-based root-finding algorithm is usually employed which in turn necessitates to solve a saddle point system at every Newton iteration. The involved linear systems being large scale and ill-conditioned, effective linear solvers must be implemented. Here, we develop and test several methods for solving the saddle point systems, considering in particular the LU factorization, as direct approach, and the preconditioned generalized minimal residual (ΡGMRES) solver, an iterative approach. We apply the various solvers within the root-finding algorithm for Flow over backward facing step systems. The particularity of Flow over backward facing step system is an interesting case for studying the performance and solution strategy of a turbulence model. In this case, the flow is subjected to a sudden increase of cross-sectional area, resulting in a separation of flow starting at the point of expansion, making the system of differential equations particularly stiff. We assess the performance of the direct and iterative solvers in terms of computational time, numbers of Newton iterations and time steps. 展开更多
关键词 Navier-Stokes Equation ΡGMRES Direct Solver Schur Approach PRECONDITIONER
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ENTIRE SOLUTIONS OF HIGHER ORDER DIFFERENTIAL EQUATIONS WITH ENTIRE COEFFICIENTS HAVING THE SAME ORDER
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作者 冯子恒 黄志波 李叶舟 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期355-368,共14页
In this paper,we consider entire solutions of higher order homogeneous differential equations with the entire coefficients having the same order,and prove that the entire solutions are of infinite lower order.The prop... In this paper,we consider entire solutions of higher order homogeneous differential equations with the entire coefficients having the same order,and prove that the entire solutions are of infinite lower order.The properties on the radial distribution,the limit direction of the Julia set and the existence of a Baker wandering domain of the entire solutions are also discussed. 展开更多
关键词 entire solutions radial order Julia limiting direction Baker wandering domain transcendental direction
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临床药师参与1例心力衰竭、心肌梗死合并房颤患者的药物治疗
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作者 受国徽 苏会源 李波霞 《海峡药学》 2024年第3期95-98,共4页
目的梳理复杂治疗方案后的抗栓方案,重整抗栓药物和疗程,纠正不合理用药,促进合理用药。方法临床药师介入1例心力衰竭、多次因心肌梗死植入多枚支架,合并房颤,行射频消融和左心耳封堵患者的药物治疗,重整抗栓药物方案,并全程监控治疗药... 目的梳理复杂治疗方案后的抗栓方案,重整抗栓药物和疗程,纠正不合理用药,促进合理用药。方法临床药师介入1例心力衰竭、多次因心肌梗死植入多枚支架,合并房颤,行射频消融和左心耳封堵患者的药物治疗,重整抗栓药物方案,并全程监控治疗药物,就不合理用药提出警示。结果患者明显好转,住院及出院随访期间未发生不良事件。结论临床药师的参与有助于精细化管理患者的药物治疗方案,并及时纠正不合理用药,更好的为患者服务。 展开更多
关键词 心力衰竭 心肌梗死 PCI支架植入术 直接口服抗凝药物(DOAC Direct oral anticoagulants) 利伐沙班 新活素(注射用重组人脑利钠肽) 沙库巴曲缬沙坦
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Ascertaining the influences of auxiliary qubits on the Einstein–Podolsky–Rosen steering and its directions
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作者 邢玲玲 杨欢 +1 位作者 张刚 孔敏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期213-221,共9页
Einstein–Podolsky–Rosen(EPR) steering is an example of nontrivial quantum nonlocality and characteristic in the non-classical world.The directivity(or asymmetry) is a fascinating trait of EPR steering,and it is diff... Einstein–Podolsky–Rosen(EPR) steering is an example of nontrivial quantum nonlocality and characteristic in the non-classical world.The directivity(or asymmetry) is a fascinating trait of EPR steering,and it is different from other quantum nonlocalities.Here,we consider the strategy in which two atoms compose a two-qubit X state,and the two atoms are owned by Alice and Bob,respectively.The atom of Alice suffers from a reservoir,and the atom of Bob couples with a bit flip channel.The influences of auxiliary qubits on EPR steering and its directions are revealed by means of the entropy uncertainty relation.The results indicate that EPR steering declines with growing time t when adding fewer auxiliary qubits.The EPR steering behaves as damped oscillation when introducing more auxiliary qubits in the strong coupling regime.In the weak coupling regime,the EPR steering monotonously decreases as t increases when coupling auxiliary qubits.The increases in auxiliary qubits are responsible for the fact that the steerability from Alice to Bob(or from Bob to Alice) can be more effectively revealed.Notably,the introductions of more auxiliary qubits can change the situation that steerability from Alice to Bob is certain to a situation in which steerability from Bob to Alice is certain. 展开更多
关键词 auxiliary qubits EPR steering DIRECTIONS influence
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