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Strategic Investment in Transmission and Energy Storage in Electricity Markets

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Journal of Modern power Systems and Clean Energy 2022年第1期10卷 179-191页

作者： Kunpeng Tian Weiqing sun dong Han Department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghaiChina Department of Electrical Engineering University of Shanghai for Science and TechnologyShanghaiChina

The variability of renewable energy and transmission congestion provide opportunities for arbitrage by merchants in deregulated electricity *** strategically invest to maximize their *** paper proposes a joint investment framework for renewable energy,transmission lines,and energy storage using the Stackelberg game *** the upper level,merchants implement investment and operation strategies for deregulated transmission and energy storage to maximize *** the middle level,central planners seek to maximize social welfare through investments in centralized renewable energy and energy *** the lower level,independent system operators jointly optimize the energy and reserve markets to minimize the total operating *** are remunerated through financial rights,which are a settlement method based on locational marginal *** trilevel optimization problem is reformulated as a tractable single-level one using Karush-Kuhn-Tucker(KKT)conditions and strong duality *** interaction between merchants and central planners is studied with an example based on the IEEE 30-bus test *** assignment of weight coefficients to the corresponding stochastic scenarios can help merchants avoid investment risk,and their effectiveness is verified with the IEEE 118-bus test system.

关键词： Strategic investment Stackelberg game model financial right locational marginal price merchant central planner

Investigation on Active Thermal Control Method with pool Boiling Heat Transfer at Low Pressure

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Journal of Thermal Science 2018年第3期27卷 277-284页

作者： sun Chuang GUO dong WANG Zhengyu sun Fengxian School of Energy Science and Engineering Harbin Institute of Technology School of power and Energy Engineering Harbin Engineering University

In order to maintain a desirable temperature level of electronic equipment at low pressure, the thermal control performance with pool boiling heat transfer of water was examined based on experimental measurement. The total setup was designed and performed to accomplish the experiment with the pressure range from 4.5 kPa to 20 kPa and the heat flux between 6 kW/m^2 and 20 kW/m^2. The chosen material of the heat surface was alu- minium alloy and the test cavity had the capability of varying the direction for the heat surface from vertical to horizontal directions. Through this study, the steady and transient temperature of the heat surface at different pressures and directions were obtained. Although the temperature non-uniformity of the heat surface from the centre to the edge could reach 10℃ for the aluminium alloy due to the varying pressures, the whole temperature results successfully satisfied with the thermal control requirements for electronic equipment, and the temperature control effect of the vertically oriented direction was better than that of the borizontally oriented direction. Moreover, the behaviour of bubbles generating and detaching from the heat surface was recorded by a high-resolution camera, so as to understand the pool boiling heat transfer mechanism at low-load heat flux. These pictures showed that the bubbles departure diameter becomes larger, and departure frequency was slower at low pressure, in contrast to 1.0 atm.

关键词： pool Boiling Heat Transfer Water Low Pressure Low-load Heat Flux Experiment Measurement

Event-triggered receding horizon control via actor-critic design

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Science China(Information Sciences) 2020年第5期63卷 131-145页

作者： Lu dong Xin YUAN Changyin sun School of Automation Southeast University College of Electronics and Information Engineering Tongji University Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast University

In this paper, we propose a novel event-triggered near-optimal control for nonlinear continuoustime systems. The receding horizon principle is utilized to improve the system robustness and obtain better dynamic control performance. In the proposed structure, we first decompose the infinite horizon optimal control into a series of finite horizon optimal problems. Then a learning strategy is adopted, in which an actor network is employed to approximate the cost function and an critic network is used to learn the optimal control law in each finite horizon. Furthermore, in order to reduce the computational cost and transmission cost, an event-triggered strategy is applied. We design an adaptive trigger condition, so that the signal transmissions and controller updates are conducted in an aperiodic way. Detailed stability analysis shows that the nonlinear system with the developed event-triggered optimal control policy is asymptotically *** results on a single-link robot arm with different noise types have demonstrated the effectiveness of the proposed method.

关键词： event-triggered control receding horizon control actor-critic design optimal control nonlinear systems neural networks

Day-ahead scheduling based on reinforcement learning with hybrid action space

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Journal of Systems Engineering and Electronics 2022年第3期33卷 693-705页

作者： CAO Jingyu dong Lu sun Changyin School of Automation Southeast UniversityNanjing 210096China School of Cyber Science and Engineering Southeast UniversityNanjing 211189China

Driven by the improvement of the smart grid,the active distribution network(ADN)has attracted much attention due to its characteristic of active *** making full use of electricity price signals for optimal scheduling,the total cost of the ADN can be ***,the optimal dayahead scheduling problem is challenging since the future electricity price is ***,in ADN,some schedulable variables are continuous while some schedulable variables are discrete,which increases the difficulty of determining the optimal scheduling *** this paper,the day-ahead scheduling problem of the ADN is formulated as a Markov decision process(MDP)with continuous-discrete hybrid action ***,an algorithm based on multi-agent hybrid reinforcement learning(HRL)is proposed to obtain the optimal scheduling *** proposed algorithm adopts the structure of centralized training and decentralized execution,and different methods are applied to determine the selection policy of continuous scheduling variables and discrete scheduling *** simulation experiment results demonstrate the effectiveness of the algorithm.

关键词： day-ahead scheduling active distribution network(ADN) reinforcement learning hybrid action space

Experimental investigation on SPS casing treatment with bias flow

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Chinese Journal of Aeronautics 2014年第6期27卷 1352-1362页

作者： dong Xu Liu Xiaohua sun Dakun sun Xiaofeng School of Energy and power Engineering Beihang University Aeroengine Airworthiness Certification Center Preparatory Office China Academy of Civil Aviation Science and Technology

Generally, casing treatment（CT） is a passivity method to enhance the stall margin of fan/compressor. A novel casing treatment based on the small disturbance theory and vortex and wave interaction suggestion is a method combining passive control and active control, which has been proved effective at enhancing the stall margin of fan/compressor in experiment. In order to investigate the mechanism of this kind of casing treatment, an experimental investigation of a stall precursor-suppressed（SPS） casing treatment with air suction or blowing air is conducted in the present paper. The SPS casing treatment is designed to suppressing stall precursors to realize stall margin enhancement in turbomachinery. The experimental results show that the casing treatment with blowing air of small quantity can improve the stall margin by about 8% with about 1% efficiency loss. By contrast, the SPS casing treatment with micro-bias flow does not improve the stall margin much more than that without bias flow, even worse. Meanwhile, the present investigation has also attempted to reveal the mechanism of stall margin improvement with the casing *** is found that the stall margin improvements vary with the modification of the unsteady shedding flow and the unsteady wall boundary impedance. The experimental results agree fairly well with the theoretical prediction using a flow stability model of rotating stall.

关键词： Air blowing Air suction Casing treatment Fan stability Rotating stall

Characteristics of Mechanical Properties and Microstructure for 316L Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2011年第11期18卷 53-59页

作者： SONG Ren-bo XIANG Jian-ying HOU dong-po School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

A comparative study on mechanical properties and microstructure of 316L austenitic stainless steel between solution treated specimen and hot rolled specimen was conducted. After a specimen was subjected to solution treatment at 1 050 ℃ for 6 min, its mechanical properties were determined through tensile and hardness tests. Based on the true stress vs true strain and engineering stress vs engineering strain flow curves, the work hardening rate has been explored. The results show that the solution treated specimen has an excellent combination of strength and elongation, and that this steel is easy to work-hardening during deformation. Optical microscope, scanning electron micro- scope, transmission electron microscope and X-ray diffraction examinations were conducted, these reveal that twins in 316L austenitic stainless steel can be divided into suspended twin and transgranular twin which have different for mation mechanisms in growth, and that the deformation induced martensite nucleated and grown in the shear band intersections can be observed, and that the fracture surfaces are mainly composed of dimples and exhibit a tough fracture character.

关键词： 316L mechanical property twin martensite fracture morphology

Occupancy of rooms in urban residential buildings by users in cold areas of China

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Building Simulation 2023年第3期16卷 483-497页

作者： Qi dong Zikai Ma Cheng sun School of Architecture Harbin Institute of TechnologyHarbin 150006China Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologyHarbin 150006China

Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption *** study investigated eight families in cold areas of China based on occupancy measurements obtained in four main rooms,i.e.,living room,bedroom,kitchen,and *** particular,we analyzed the duration of user occupancy and hourly mean occupancy,and characterized their regular and random *** to the results,we developed an event-based occupancy model using an inhomogeneous Markov chain,where the rooms were modeled and daily events were divided into three categories according to their *** established a new method for conversion between event characteristic parameters and a transition probability matrix,as well as an overlap avoidance method for active *** model was then validated using real *** results showed that the model performed well in terms of two evaluation *** model should improve the accuracy of simulations of occupancy.

关键词： event occupancy urban residential building simulation cold areas of China

Data-Based Optimal Tracking of Autonomous Nonlinear Switching Systems

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 227-238页

作者： Xiaofeng Li Lu dong Changyin sun the School of Automation Southeast UniversityNanjing 210096 the Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China the College of Electronics and Information Engineering Tongji UniversityShanghai 201804China

In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching *** system state is forced to track the reference signal by minimizing the performance ***,the problem is transformed to solve the corresponding Bellman optimality equation in terms of the Q-function(also named as action value function).Then,an iterative algorithm based on adaptive dynamic programming(ADP)is developed to find the optimal solution which is totally based on sampled *** linear-in-parameter(LIP)neural network is taken as the value function *** the presence of approximation error at each iteration step,the generated approximated value function sequence is proved to be boundedness around the exact optimal solution under some verifiable ***,the effect that the learning process will be terminated after a finite number of iterations is investigated in this paper.A sufficient condition for asymptotically stability of the tracking error is ***,the effectiveness of the algorithm is demonstrated with three simulation examples.

关键词： Adaptive dynamic programming approximation error data-based control Q-learning switching system

Heart failure research in China： current status and future direction

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Science Bulletin 2016年第23期61卷 1793-1801页

作者： Yuangui Zhu Ruijuan sun Erdan dong Department of Health Sciences The National Natural Science Foundation of China Beijing 100085 China

Heart failure is a major public health problem worldwide. Despite advances in the therapy and care of heart failure, morbidity and mortality remain persistently high. Recent years have witnessed major breakthroughs in the investigations of pathogenesis, prevention, and treatment of heart failure in China. It is noteworthy that the continuing and growing support from funding agencies in China including the National Natural Science Foundation of China has yielded substantial effects on the basic and clinical research in heart failure in the last decade. In this review, we provide an update on the current status of heart failure research, both basic and translational/clinical, in China, including funding and publications. We also discuss the future challenges and possible strategies in improving our understanding and management of heart failure in China.

关键词： Heart failure Basic research Translational research Clinical research China