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Polarization-Induced Proton Adsorption and Charge Separation in Pyrene-Based Conjugated Microporous Polymers Via Substituent Regulation for Efficient Photocatalytic Hydrogen Evolution

SSRN

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SSRN 2023年

作者： Ren, Runtang Jiao, Zhengxu Li, Zhanfeng Tian, Yue Liu, Baoyou Yue, Gang Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan030024 China Institute of Carbon Materials College of Materials Science and Engineering Taiyuan University of Technology Taiyuan030024 China Technology Innovation Center Ningxia Sinostar Display Material Co. Ltd. Yinchuan750003 China

Constructing photocatalysts with efficient light-harvesting abilities and charge separation properties is highly promising but still challenging for boosting photocatalytic hydrogen evolution from water. Herein, we report a simple and general polarization strategy through substituent regulation such as fluorination, chlorination and cyanation, to promote the photon capture and charge separation and unveil the latent structure–property–activity relationship in pyrene-based conjugated microporous polymers (CMPs). Notably, the introduction of fluorine, chlorine and cyano substituents onto the well-known full donor pyrene-benzene-based CMP network (Py-B) could induce a strong dipole along C–F/–Cl/–CN bonds and the backbone local polarization enhancement due to their strong electron-withdrawing ability, which afforded CMPs have a variety of superior effects such as narrowing band gaps, expanding optical absorption, improving interfacial wettability and solid-state morphology, and promoting charge separation inside organic photocatalysts. As a result, 1.73/2.50/4.69-fold increases of the hydrogen evolution rates of the –F/–Cl/–CN modified CMPs under visible light (λ > 420 nm) irradiation without Pt co-catalysts can be obtained in comparison with the counterpart Py-B (28.5/41.3/77.4 mmol g−1 h−1 vs 16.5 mmol g−1 h−1). Impressively, we find that the photocatalytic performance of this series of photocatalysts is linearly related to the dipole moment of polymers. Our studies reveal that the backbone local polarization enhancement induced by the substituent regulation could achieve high-performance organic photocatalysts toward solar-to-chemical energy conversion. © 2023, The Authors. All rights reserved.

关键词： Polarization

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Adaptive Enhancement Technology for Screen Content Photos 17th

Adaptive Enhancement Technology for Screen Content Photos

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17th International Forum on Digital TV and Wireless Multimedia Communication, IFTC 2020

作者： Zhou, Yazhen Kyefondeme, Dakurah Collins Zhou, Huayi Zhao, Min Guo, Nan Wu, Li Faculty of Information Technology Beijing University of Technology Beijing China Key Laboratory of Artificial Intelligence Ministry of Education Shanghai China Engineering Research Center of Intelligent Perception and Autonomous Control Ministry of Education Beijing China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing China Beijing Artificial Intelligence Institute Beijing China

ISBN: (纸本)9789811611933

Recent years have witnessed the widespread applications of mobiles and other portable electronic devices, involving a variety of screen content photos. Different from natural scene photos, screen content photos are composed of more lines, fewer colors and unique text messages. Thus, it is difficult to realize the satisfactory enhancement effect of screen content photos using traditional image enhancement technology since they are designed for the natural scene. In this paper, we develop a novel enhancement model for screen content photos by considering text and picture separately. To be specific, we first use a fully convolutional network to divide a screen content photo into three independent parts: picture region, foreground text region, and background. Second, an optimal modification of histogram is used to automatically enhance the picture region’s contrast, and the guided image filter is used to enhance the foreground text region. Third, the enhanced picture region, the enhanced foreground text region, and background are fused to obtain the final enhanced image. Experimental results show that our model has produced less noise and derived outstanding enhancement effect than the popular enhancement techniques. © 2021, Springer Nature Singapore Pte Ltd.

关键词： Image segmentation

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Probabilistic Planning of Transmission Network Considering Operational Flexibility of Power system

Probabilistic Planning of Transmission Network Considering O...

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Smart Power & Internet Energy systems (SPIES), International Conference on

作者： Jianjie Li Ping Li Peng Li Junshao Guo Mingqiang Wang Binzhou Electric Company Binzhou China Key Laboratory of Power System Intelligent Dispatch and Control Ministry of Education Shandong University Jinan China

The uncertainties about equipment failure will bring great challenges to the operation of transmission network. Therefore, it is important for transmission network to possess sufficient flexibility to accommodate the fluctuation of load and deal with unit failures. This paper proposes a probabilistic planning model of transmission network considering operational flexibility, which makes decision-making optimization for transmission network planning and reduces the influence of uncertainties about equipment failure. Moreover, the proposed model introduces the probability and expectation of up-flexibility-not-supplied (UFNS) and expected-energy-not-supplied (EENS), then uses penalty cost to quantify them, which enhances the reliability and economy of transmission network planning. Furthermore, the absolute value linearization method is used to linearize the expectation of UFNS and EENS, which greatly improves the calculation efficiency. The proposed model is solved using the CPLEX solver in General Algebraic Modeling system (GAMS). The practicality of model is verified by the IEEE-RTS system.

关键词： Uncertainty Fluctuations Probabilistic logic Software Planning Power system reliability Software reliability

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Robust Finite-Time Stabilization of Stochastic Parabolic PDE systems via Non-Fragile Spatial Sampled-Data control

Robust Finite-Time Stabilization of Stochastic Parabolic PDE...

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IEEE Conference on Decision and control

作者： Xiaofang Hu Feida Song Leimin Wang School of Automation China University of Geosciences Wuhan China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan China

This paper addresses the robust finite-time stabi-lization (FTS) issue for stochastic parabolic PDE systems via non-fragile spatial sampled-data control scheme. First, a class of distributed parameter systems characterized by the delayed stochastic parabolic partial differential equation is developed for analyzing the effects of stochastic disturbance, structural uncertainty, and discrete delay on the system performance. Then, a non-fragile spatial sampled-data control scheme is established by setting sampling points in the spatial domain, which effectively saves communication resources and ensures that the closed-loop system maintains good performance when the controller is perturbed. Moreover, based on the partial differential equation theory, stochastic analysis approach, and the extended Wirtinger's inequality technique, several criteria are provided to ensure the robust FTS of stochastic parabolic PDE systems in the mean square sense. Lastly, a numerical example is provided to verify the feasibility of the suggested stabilization criteria and control scheme.

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Evaluation of Landslide Susceptibility Based on SVM with GWO Algorithm

Evaluation of Landslide Susceptibility Based on SVM with GWO...

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Chinese control Conference (CCC)

作者： Yuxuan Zeng Chengda Lu Yutong Pan Hanqi Qu Min Wu School of Automation China University of Geosciences Wuhan China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China Ministry of Education Engineering Research Center of Intelligent Technology for Geo-Exploration Wuhan China

Since landslide is one of the most universal natural disasters in China, the study of regional landslide susceptibility evaluation is important to protect people's lives and property. This paper analyzes the geospatial characteristics of the Zigui-Badong section in the Three Gorges. By Pearson correlation analysis methodselects, nine impact factors of landslide susceptibility are extracted from the aspects of topography and geomorphology, geological environment, and hydrological conditions, used to establish the evaluation index system of landslide susceptibility. On the above data basis, the paper applies a support vector machine (SVM) model and an SVM model for gray wolf optimization (GWO) to the susceptibility evaluation of landslides, and product landslide susceptibility index maps according to the results. The research area is divided into four regions by jenks method on the map: high-risk, medium-risk, low-risk, and very low-risk areas. Applying the accuracy, confusion matrix, and receiver operating characteristic (ROC) curve to evaluate the model, The prediction accuracy of the GWO-SVM model and the SVM model is 88.55 % and 82.82 % respectively, the comparison proves that the GWO-SVM model is much more accurate, which can provide a reference for the study of regional landslide susceptibility.

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Synchronization Stability of PLL-Based Power Converters Connected to Weak AC Grid 6

Synchronization Stability of PLL-Based Power Converters Conn...

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6th Asia Conference on Power and Electrical Engineering, ACPEE 2021

作者： Mei, Limin Ding, Lei Wang, Zhihao Cai, Deyu Ding, Ran Wang, Jingran Xu, Haixiang Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan China State Grid Jibei Electric Power Company Limited Electric Power Dispatching and Control Center Beijing China

ISBN: (纸本)9781728191591

In this paper, the synchronization stability of converter system based on the phase-locked loop (PLL) is studied, especially when it is connected to a weak AC grid. First, the small signal model considered PLL, power control, current control and voltage feedforward (VFF) control is built. The open-loop transfer function can analyze the stability of the system but hides the dynamic of PLL. So the conjugated circuit is proposed, which describes the dynamics of PLL and the other part separately. Based on the Bode diagrams, we explore how the grid impedance and converter controller parameters influence the stability of the system. In order to verify the analysis results, simulations are conducted in MATLAB/Simulink. © 2021 IEEE.

关键词： Phase locked loops

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control strategy for the rotor position angle of permanent magnet synchronous motor based on error extended state observer

Control strategy for the rotor position angle of permanent m...

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Chinese control and Decision Conference, CCDC

作者： Lixiang Ma Susu Yu Bingyou Liu Anhui Institute of Information Technology Wuhu China College of Electrical Engineering Anhui Polytechnic University Key Laboratory of Advanced Perception and Intelligent Control of High-End Equipment Ministry of Education Wuhu China

In order to solve the problems of strong coupling, variable parameters and nonlinearity of permanent magnet synchronous motor (PMSM), an expanded state observer based on error is proposed in this paper to achieve fast response, accurate tracking and strong anti-disturbance control performance of the rotor position and angle of PMSM. Firstly, a new nonlinear function is designed to replace the nonlinear function of the extended state observer (ESO) in the traditional active disturbance rejection controller (ADRC). Secondly, based on the improved nonlinear function, the structure of ESO is improved according to the error principle. Finally, the position and Angle control system based on PMSM is simulated. Simulation results show that the ADRC based on error ESO has better response speed, tracking accuracy and anti-disturbance performance than the traditional ADRC.

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Dynamics Modeling Method of Offshore Drilling Experimental system Based on Double-Layer Stewart Parallel Mechanism

Dynamics Modeling Method of Offshore Drilling Experimental S...

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第42届中国控制会议

作者： Chenxuan Wang Zhejiaqi Ma Chengda Lu Sheng Du Min Wu School of Future Technology China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education School of Automation China University of Geosciences

Establishing the dynamics model of the offshore drilling experimental system can better complete the offshore drilling test in the laboratory environment and reduce the cost of testing.A dynamical modeling method for the offshore drilling experimental system built on the double-layer Stewart parallel mechanism is ***,the kinematic and dynamical characteristics of the double-layer Stewart parallel mechanism are combined with the Lagrange method and the virtual work method to establish the dynamics model of the *** a parameter identification scheme is designed using a nonlinear gray system estimation method based on the trust-domain reflection algorithm,and the model parameters are *** model is downscaled to improve the feasibility of the identification scheme and the accuracy of the identified *** actual experimental system data verify this model's correctness and the model parameters' accuracy.

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Slewing control of Overhead Crane Based on State-enhance Coupling Method

Slewing Control of Overhead Crane Based on State-enhance Cou...

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第43届中国控制会议

作者： Rui Liu Biao Lu Jinyang Dong Weili Ding The 6th Research Institute of China Electronic Corporation Institute of Intelligence Technology and Robotic Systems Shenzhen Research Institute of Nankai University Engineering Research Center of Intelligent Control System and Intelligent Equipment Ministry of Education Yanshan University National Key Laboratory of Key Technologies for Lifting Machinery Yanshan University

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

Cranes which are frequently utilized as sizable machinery, are widely used across a range of settings, including warehouses, distribution hubs, harbors, steel plants, and manufacturing facilities. However, the current researches on cranes have paid insufficient attention to the rotation of loads during transportation. Additionally, some of the proposed control methods fail to effectively integrate information from both actuated DOFs(degrees of freedom) and unactuated DOFs, leading to a loss of controller robustness. In this paper, we establish an overhead crane model with a slewing mechanism, focusing on the analysis of crane's lifting and rotating motion. Based on that, a nonlinear controller is proposed for load slewing control. The stability of the controller is proven using Lyapunov techniques and LaSalle's invariance theorem. The effectiveness and robustness of the controller are validated through numerical simulations.

关键词： Load Rotation Nonlinear controller Robustness

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Semantic Segmentation of Historical Landslide Based on Improved U-Net

Semantic Segmentation of Historical Landslide Based on Impro...

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Chinese control Conference (CCC)

作者： Hanqi Qu Chengda Lu Yutong Pan Yuxuan Zeng Min Wu School of Automation China University of Geosciences Wuhan China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China Engineering Research Center of Intelligent Technology for Geo- Exploration Ministry of Education Wuhan China

Landslide disasters are extremely destructive. Accurate identification of landslides plays an important role in disaster assessment, loss control and post-disaster reconstruction. This paper proposes a semantic segmentation landslide identification method based on improved U-Net. The deep convolution neural network and jump connection method is used for end-to-end semantic segmentation to achieve deep feature extraction and fusion of different receptive fields, thus enriching feature information. SENet modules are adopted to enhance the ability of the model to extract important features, so as to further improve the accuracy of model recognition. Extensive experiments show that our improved U-Net achieves better performance than the original algorithm on our landslide datasets. The results of Iou are improved by 4.12% which demonstrates our work is of great significance for the research of landslide area identification. Finally, the model is deployed to the web and applied to the geological hazard intelligent monitoring system to realize the landslide identification task.

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