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Frequency effect on p-nitrophenol degradation under conditions of strict acoustic and electric control

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Water science and Engineering 2011年第1期4卷 74-82页

作者： chang-ping ZHU Bo HUANG Qing-bang HAN Cai-hua NI Guang-jun ZHU Ming-hua liu Ming-lei SHAN College of computer and lnformation Engineering Hohai University Changzhou 213022 P. R. China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 P. R. China College of Information and electrical Engineering China University of Mining and Technology Xuzhou 221008 P. R. China school of Chemical and Material Engineering Jiangnan University Wuxi 214122 P. R. China

The process of decomposing p-nitrophenol （PNP） with power ultrasound requires strict control of acoustic and electric conditions. In this study, the conditions, including acoustic power and acoustic intensity, but not ultrasonic frequency, were controlled strictly at constant levels. The absorbency and the COD concentrations of the samples were measured in order to show the variation of the sample concentration. The results show significant differences in the trend of the solution degradation rate as acoustic power increases after the PNP solution （with a concentration of ll4 mg/L and a pH value of 5.4） is irradiated for 60 min with ultrasonic frequencies of 530.8 kHz, 610.6 kHz, 855.0 kHz, and 1130.0 kHz. The degradation rate of the solution increases with time and acoustic power （acoustic intensity）. On the other hand, the degradation rate of the solution is distinctly dependent on frequency when the acoustic power and intensity are strictly controlled and maintained at constant levels, The degradation rate of the PNP solution declines with ultrasonic frequencies of 530.8 kHz, 610.6 kHz, 855.0 kHz, and 1 130.0 kHz; the COD concentration, on the contrary, increase.

关键词： ultrasonic treatment frequency effect COD concentration p-nitrophenol

Loop Closure Detection of Visual SLAM Based on Point and Line Features

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Journal of Harbin Institute of technology(New Series) 2020年第2期27卷 58-64页

作者： chang’an liu Ruiying Cheng Lijuan Zhao school of Control and computer Engineering North China Electric Power UniversityBeijing 102206China

For traditional loop closure detection algorithm,only using the vectorization of point features to build visual dictionary is likely to cause perceptual *** addition,when scene lacks texture information,the number of point features extracted from it will be small and cannot describe the image ***,this paper proposes a loop closure detection algorithm which combines point and line *** better recognize scenes with hybrid features,the building process of traditional dictionary tree is improved in the *** features with different flag bits were clustered separately to construct a mixed dictionary tree and word vectors that can represent the hybrid features,which can better describe structure and texture information of *** ensure that the similarity score between images is more reasonable,different similarity coefficients were set in different scenes,and the candidate frame with the highest similarity score was selected as the candidate closed *** show that the point line comprehensive feature was superior to the single feature in the structured scene and the strong texture scene,the recall rate of the proposed algorithm was higher than the state of the art methods when the accuracy is 100%,and the algorithm can be applied to more diverse environments.

关键词： loop closure detection SLAM visual dictionary point and line features

基于构网型控制策略的直驱型风力发电机简化模型研究

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重庆理工大学学报（自然科学） 2024年第2期38卷 295-303页

作者：李琰刘京波郇政林谭延博顾天明王新王谱宇国网冀北电力有限公司电力科学研究院(华北电力科学研究院有限责任公司) 北京100045 南京理工大学自动化学院南京210094

直驱式风力发电作为当前风力发电的普遍形式,随着其容量的增加,将导致受端电网有效惯量不断减少,呈现弱阻尼特性,增加电力系统运行风险。直驱风电场柔直并网过程中采用具有主动支撑能力的构网型控制逐渐成为研究主流,但因其控制技术、... 详细信息

直驱式风力发电作为当前风力发电的普遍形式,随着其容量的增加,将导致受端电网有效惯量不断减少,呈现弱阻尼特性,增加电力系统运行风险。直驱风电场柔直并网过程中采用具有主动支撑能力的构网型控制逐渐成为研究主流,但因其控制技术、工程应用尚处于研究阶段,需要先在仿真软件中进行测试。构网型直驱风电场并网系统需要考虑大量风机的运行特性,多台机组的接入导致仿真运行环境复杂,硬件在环系统的算力不足以达到多台机组的详细仿真要求。为减小计算压力,寻找更适合风电场并网研究的仿真模型,针对构网型控制下的直驱风机机组详细模型进行简化,采用受控电流源替代风机机侧模型的方法,进一步节省计算机算力,从输入功率/直流电压/交流电压波动3个方面进行模型对比,从模型响应曲线误差和仿真耗时2个角度对详细模型及简化模型进行评价。仿真结果表明,简化模型可以反映风电机组网侧的功率输出特性,在节省仿真耗时上具有明显优势。

关键词：直驱风机构网型控制详细/简化模型仿真耗时

An in-situ defect passivation through a green anti-solvent approach for high-efficiency and stable perovskite solar cells

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science Bulletin 2021年第14期66卷 1419-1428,M0004页

作者： chang liu lei Huang Xianyong Zhou Xingzhu wang Jianxi Yao Zhike liu Shengzhong Frank liu Wanli Ma Baomin Xu Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Department of Materials science and Engineering and Shenzhen Engineering Research and Development Center for Flexible Solar Cells Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Energy Conversion and Storage Technologies(Southern university of science and technology) Ministry of EducationShenzhen 518055China Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-electrical Energy Materials and Devices Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Alternate electrical power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education) Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Laborartory for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Institute of Functional Nano&Soft Materials Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesJoint International Research Laboratory of Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China

Surface and grain boundary defects in halide perovskite solar cells are highly detrimental,reducing efficiencies and *** halide anion and organic cation defects usually aggravate ion diffusion and material degradation on the surfaces and at the grain boundaries of perovskite *** this study,we employ an in-situ green method utilizing nontoxic cetyltrimethylammonium chloride(CTAC)and isopropanol(IPA)as anti-solvents to effectively passivate both surface and grain boundary defects in hybrid *** vacancies can be readily passivated by the chloride group due to its high electronegativity,and cation defects can be synchronously passivated by the more stable cetyltrimethylammonium *** results show that the charge trap density was significantly reduced,while the carrier recombination lifetime was markedly *** a result,the power conversion efficiency of the cell can reach 23.4%with this in-situ green *** addition,the device retains 85%of its original power conversion efficiency after 600 h of operation under illumination,showing that the stability of perovskite solar cells is improved with this in-situ passivation *** work may provide a green and effective route to improve both the stability and efficiency of perovskite solar cells.

关键词： Perovskite solar cells In-situ defect passivation Green anti-solvent

Improved RMPC Based on Piece-wised Uncertain Model for UTSG Water Level Control 25th

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Improved RMPC Based on Piece-wised Uncertain Model for UTSG ...

A new improvement of TCP based on adaptive filtering

第25届中国控制与决策会议

作者： Fuhe wang Xiangjie liu school of Control and computer Engineering North China Electric Power University

ISBN: (纸本)9781467355322

More and more attention has been drawn to hunt for better control method of the nuclear steam generator (SG) water level because poor control can lead to frequent reactor shut downs and serious accidents even. Moreover, as power level changing, the dynamic of a nuclear steam generator is also varying. In this paper, we develop an improved robust MPC based on piece-wised LPV model with polytopic uncertainty. The optimization problem adopted here is min-max strategy based on the linear matrix inequality (LMI) technique. In order to improve the dynamic of the water level, we introduce the idea of soft constraints. Finally, we show the effectiveness of the proposed control method by simulation.

关键词： Robust model predictive control U-tube steam generator Level control Linear matrix inequality

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High technology Letters 2012年第1期18卷 59-63页

作者： Li Guodong Zhao Na Jiao Dujuan Zhang Yingjie liu chang＇an school of Control and computer Engineering North China Electric Power University Beijing 102206 P.R. China National science Library Chinese Academy of Sciences Beijing 100190 P.R. China

On the basis of studying the standard TCP retransmission mechanism, this paper proposes a method to adopt the theory of adaptive filtering in the field for the estimation of round trip time （RTT）. Then this method is embedded in TCP for estimation of RTT, and defined as RTT-AF TCP. In the schemes with Only-TCP flow and with TCP and UDP flow fighting for the link, the experiment results were made and analyzed by using the standard TCP and the RTT-AF TCP. The experimental results show higher throughput and lower loss rate of packets by using RTT-AF TCP for data transmission, and achieve excellent effect.

关键词： roundtrip time (RTT) adaptive filtering RTT-AF transmission control protocol(TCP)

Detecting Icing on the Blades of a Wind Turbine Using a Deep Neural Network

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computer Modeling in Engineering & sciences 2023年第2期134卷 767-782页

作者： Tingshun Li Jiaohui Xu Zesan liu Dadi wang Wen Tan school of Control and computer Engineering North China Electric Power UniversityBeijing102206China R&D State Grid Information&Telecommunication Group Co.Beijing102211China

The blades of wind turbines located at high latitudes are often covered with ice in late autumn and winter,where this affects their capacity for power generation as well as their *** identifying the icing of the blades of wind turbines in remote areas is thus important,and a general model is needed to this *** paper proposes a universal model based on a Deep Neural Network(DNN)that uses data from the Supervisory Control and Data Acquisition(SCADA)*** datasets from SCADA are first preprocessed through undersampling,that is,they are labeled,normalized,and *** features of icing of the blades of a turbine identified in previous studies are then used to extract training data from the training dataset.A middle feature is proposed to show how a given feature is correlated with icing on the *** indicators for the model,including a reward function,are also designed to assess its predictive ***,the most suitable model is used to predict the testing data,and values of the reward function and the predictive accuracy of the model are *** proposed method can be used to relate continuously transferred features with a binary status of icing of the blades of the turbine by using variables of the middle *** results here show that an integrated indicator systemis superior to a single indicator of accuracy when evaluating the prediction model.

关键词： DNN predicting blade icing SCADA data wind power reward function

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基于深度学习的光谱图像超分辨率综述

中国图象图形学报 2024年第8期29卷 2113-2136页

作者：张涛王彬沣付莹刘松荣叶吉超单培红颜成钢杭州电子科技大学通信工程学院杭州310018 杭州电子科技大学丽水研究院丽水323000 北京理工大学计算机学院北京100081 浙江交投高速公路运营管理有限公司丽水323000 国网浙江省电力有限公司丽水323000 浙江省公众信息产业有限公司杭州310000

光谱图像超分辨率技术的目的是从低空间分辨率和光谱分辨率的图像中恢复高空间分辨率和光谱分辨率的图像,在植被调查、地质勘探、环境保护、异常检测和目标追踪等遥感领域有着广泛应用。随着深度学习的兴起,基于深度学习的光谱图像超分... 详细信息

光谱图像超分辨率技术的目的是从低空间分辨率和光谱分辨率的图像中恢复高空间分辨率和光谱分辨率的图像,在植被调查、地质勘探、环境保护、异常检测和目标追踪等遥感领域有着广泛应用。随着深度学习的兴起,基于深度学习的光谱图像超分辨率算法如雨后春笋般涌现,特别是卷积神经网络、Transformer、生成对抗网络以及深度展开网络等技术的出现使图像融合性能产生了质的飞跃。本文全面探讨和分析了不同光谱图像超分辨率任务场景下的前沿深度学习算法。首先,介绍了光谱图像超分辨率的基本概念,以及不同超分辨率场景的定义。针对单图超分辨率和融合超分辨率两大场景,从超分辨率维度、数据类型、基本框架和监督方式等多个角度详细阐述了各类方法的基本思想和特点。其次,总结了各类算法存在的局限性,并提出了进一步改进的方向。然后,简要介绍了不同融合场景中常用的数据集,并明确了各种评估指标的具体定义。对于每种超分辨率任务,从定性评估、定量评估等多个角度全面比较了代表性算法的性能。最后,总结了研究结果,并探讨了光谱图像超分辨率领域所面临的一些严峻挑战,同时对未来可能的研究方向进行了展望。所提及的算法和数据集已汇总至https://***/ColinTaoZhang/DL-based-spectral-super-resolution。

关键词：深度学习超分辨率光谱图像单图超分辨率融合超分辨率

基于GPU加速的分布式水文模型并行计算性能

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南水北调与水利科技（中英文） 2024年第1期22卷 33-38页

作者：庞超周祖昊刘佳嘉石天宇杜崇王坤于新哲黑龙江大学水利电力学院哈尔滨150080 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

针对具有物理机制的分布式水文模型对大流域、长序列模拟计算时间长、模拟速度慢的问题,引入基于GPU的并行计算技术,实现分布式水文模型WEP-L(water and energy transfer processes in large river basins)产流过程的并行化。选择鄱阳... 详细信息

针对具有物理机制的分布式水文模型对大流域、长序列模拟计算时间长、模拟速度慢的问题,引入基于GPU的并行计算技术,实现分布式水文模型WEP-L(water and energy transfer processes in large river basins)产流过程的并行化。选择鄱阳湖流域为实验区,采用计算能力为8.6的NVIDIA RTX A4000对算法性能进行测试。研究表明:提出的基于GPU的分布式水文模型并行算法具有良好的加速效果,当线程总数越接近划分的子流域个数(计算任务量)时,并行性能越好,在实验流域WEP-L模型子流域单元为8712个时,加速比最大达到2.5左右;随着计算任务量的增加,加速比逐渐增大,当实验流域WEP-L模型子流域单元增加到24897个时,加速比能达到3.5,表明GPU并行算法在大尺度流域分布式水文模型计算中具有良好的发展潜力。

关键词：基于GPU的并行算法物理机制分布式水文模型 WEP-L模型计算性能