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- Guo, Guodong, et al.
(författare)
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Safe multi-agent deep reinforcement learning for real-time decentralized control of inverter based renewable energy resources considering communication delay
- 2023
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 349
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Tidskriftsartikel (refereegranskat)abstract
- The increasing penetration of distributed renewable energy resources brings a great challenge for real-time voltage security of distribution grids. The paper proposes a safe multi-agent deep reinforcement learning (MADRL) algorithm for real-time control of inverter-based Volt-Var control (VVC) in distribution grids considering communication delay to minimize the network power loss, while maintaining the nodal voltages in a safe range. The multi-agent VVC is modeled as a constrained Markov game, which is solved by the MADRL algorithm. In the training stage, the safety projection is added to the combined policy to analytically solve an action correction formulation to promote more efficient and safe exploration. In the real-time decision-making stage, a state synchronization block is designed to impute the data under the latest timestamp as the input of the agents deployed in a distributed manner, to avoid instability caused by communication delay. The simulation results show that the proposed algorithm performs well in safe exploration, and also achieves better performance under communication delay.
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| 2. |
- Jiang, Tao, et al.
(författare)
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Guest Editorial : Special issue on flexible and resilient urban energy systems
- 2023
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Ingår i: International Journal of Electrical Power & Energy Systems. - : Elsevier BV. - 0142-0615 .- 1879-3517. ; 154, s. 109439-
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Forskningsöversikt (refereegranskat)abstract
- This guest editorial summarizes the topics and the papers selected for the Special Issue on Flexible and Resilient Urban Energy Systems. After rigorous reviewing process, 21 papers are accepted for publication. These 21 accepted papers cover various aspects of urban energy systems and are distributed as following: situational awareness of urban energy systems (2 papers), quantification metrics of flexibility and resilience of urban energy systems (3 papers), vulnerability modeling of urban energy systems under various extreme events (3 papers), planning of flexible and resilient urban energy systems (4 papers), robust and resilient operation and control of urban energy systems (4 papers), recovery and restoration strategy of urban energy systems (2 papers), and coordination and interoperability of interconnected energy systems (3 papers). The Guest Editorial Board hopes this Special Issue can provide a valuable information for future research and advancements in the field of flexible and resilient urban energy systems.
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| 3. |
- Li, Hansen, et al.
(författare)
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Chan-Chuang and resistance exercise for drug rehabilitation : a randomized controlled trial among Chinese male methamphetamine users
- 2023
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Ingår i: Frontiers In Public Health. - : World Academic Publishing Co., Limited. - 2296-2565. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To examine the health benefits of Chan-Chuang and resistance exercise.METHODS: We deployed an 8-week randomized controlled trial, in which 76 male methamphetamine users were allocated to control (n = 25), Chan-Chuang (n = 26), and residence exercise groups (n = 25). Our primary outcomes were drug craving, mental wellbeing, sleep quality, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP). Our secondary outcomes were body mass index (BMI), vital capacity, grip strength, balance, and vertical jump.RESULTS: Chan-Chuang exercise resulted in reduced HR, DBP, and MAP, along with improvements in vital capacity, grip strength, and balance compared to the control group. Resistance exercise reduced SBP and MAP, and also improved vital capacity, grip strength, balance, and vertical jump.CONCLUSION: These findings may support the role of Chan-Chuang and resistance exercise in maintaining the physical fitness of methamphetamine users at mandatory detention centers.
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