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Localization method of subsynchronous oscillation source based on high-resolution time-frequency distribution image and CNN

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Global Energy Interconnection 2024年第1期7卷 1-13页

作者： Hui Liu Yundan cheng yanhui Xu Guanqun Sun Rusi Chen Xiaodong Yu Institute of Electric Power Systems School of Electrical and Electronic EngineeringNorth China Electric Power UniversityBeijing 102206P.R.China Electric Power Research Institute of State Grid Hubei Electric Power Co. Ltd.Wuhan 430077P.R.China Central China Branch of State Grid Corporation of China Wuhan 430077P.R.China

The penetration of new energy sources such as wind power is increasing,which consequently increases the occurrence rate of subsynchronous oscillation events.However,existing subsynchronous oscillation source-identification methods primarily analyze fixed-mode oscillations and rarely consider time-varying features,such as frequency drift,caused by the random volatility of wind farms when oscillations occur.This paper proposes a subsynchronous oscillation sourcelocalization method that involves an enhanced short-time Fourier transform and a convolutional neural network(CNN).First,an enhanced STFT is performed to secure high-resolution time-frequency distribution(TFD)images from the measured data of the generation unit ports.Next,these TFD images are amalgamated to form a subsynchronous oscillation feature map that serves as input to the CNN to train the localization model.Ultimately,the trained CNN model realizes the online localization of subsynchronous oscillation sources.The effectiveness and accuracy of the proposed method are validated via multimachine system models simulating forced and natural oscillation events using the Power Systems Computer Aided Design platform.Test results show that the proposed method can localize subsynchronous oscillation sources online while considering unpredictable fluctuations in wind farms,thus providing a foundation for oscillation suppression in practical engineering scenarios.

关键词： Subsynchronous oscillation source localization Synchronous squeezing transform Enhanced short-time Fourier transform Convolutional neural networks

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A novel method for the green utilization of waste fried oil

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Particuology 2024年第1期84卷 1-11页

作者： Gan cheng Mengni Zhang Yang Lu yanhui Zhang Bin Lin Ee Von Lau College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo454003China Henan Key Laboratory for Green and Efficient Mining&Comprehensive Utilization of Mineral Resources Henan Polytechnic UniversityJiaozuo454003China Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuo454003China School of Engineering Monash University MalaysiaSubang JayaSelangor47500Malaysia

Waste fried oil was studied to prepare three different types of detergent such as soap,liquid soap and soap powder via saponification process.The preparation conditions of soap base were optimized by orthogonal experiment.The specific preparation processes included waste fried oil treatment,orange peel extract preparation,saponification,demoulding and drying.Results showed that the optimal con-ditions for saponification were as follows:ratio of pure waste fried oil to coconut oil=6∶4,alkali liquor(NaOH)mass fraction 30%,saponification temperature 70℃,orange peel extract concentration 15%.The mature soap was then used to make liquid soap and soap powder by surfactant(sodium dodecylbenzene sulfonate,coconut diethanol amide)addition,followed by grinding.The prepared detergent conforms to the production standard of strong decontamination ability,possesses stable performance,is gentle to skin and non-toxic.

关键词： Waste fried oil Detergent Saponification Decolorization

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Dynamic Model and Motion Characteristics of an Underwater Glider with Manta-inspired Wings

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Journal of Bionic Engineering 2022年第1期19卷 1-15页

作者： Yaqiang Zhu Yuhong Liu Lianhong Zhang yanhui Wang Wendong Niu cheng Huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China

An underwater glider with bionic wings controlled by two operating modes is proposed to perform a variety of marine exploration tasks.The system composition of the vehicle and the structural design of wings inspired by manta ray are presented.The bionic wings can keep outstretched or realize oscillating motions according to the operating modes of the vehicle.A universal dynamic model of the vehicle was derived from multibody theory.Gliding,sailing and steering motions were simulated based on the dynamic model to illustrate the dynamic behaviors of the vehicle under different types of propulsion techniques.The results obtained through simulated calculation are basically consistent with the experimental data,which indicate that the developed dynamic model is applicable to describe the motion characteristics of the vehicle.Experiments were conducted in coastal area to analyze the propulsive characteristics of the bionic wings and sea trials involving multifarious motions were carried out,the applicability of the vehicle in marine environment was verified.

关键词： Underwater glider Bionic wing Oscillatory propulsion Dynamic model

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Design,hydrodynamic analysis,and testing of a bioinspired controllable wing mechanism with multi-locomotion modes for hybrid-driven underwater gliders

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Science China(Technological Sciences) 2021年第12期64卷 2688-2708页

作者： SUN TongShuai WANG yanhui YANG ShaoQiong WANG cheng ZHANG LianHong Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China Qingdao Pilot National Laboratory for Marine Science and Technology(QNLM) Qingdao 266237China

Hybrid-driven technology,which can improve the sailing performance of underwater gliders(UGs),has been successfully used in ocean observation.However,a hybrid-driven UG(HUG)with an added tail propeller is still unable to achieve backward and turning motion with a body length radius,and the hydrodynamic pitch moment acting on the HUG that is mainly caused by the fixed-wing makes it difficult to achieve high-precision attitude control during fixed-depth navigation.To solve this problem,a two-degree-of-freedom bioinspired controllable wing mechanism(CWM)is proposed to improve the maneuverability and cruising ability of HUGs.The CWM can realize five motion modes:modifying the dihedral angle or anhedral angle,changing the frontal area of the wing,switching the wing from horizontal to be a vertical rudder,flapping the wing as propulsion,and rotating the wing as a vector propeller.First,the design process of the CWM is provided,and hydrodynamic forces in each motion mode of three CWMs with different trailing edge sweepback angles(TESA)and attitude angles are analyzed through computational fluid dynamics simulation.The relationship between hydrodynamics and the attitude angles or TESA of the CWM is analyzed.Then,experiments are conducted to measure the hydrodynamics of the CWM when it is in a flapping wing mode and rotating the wing as a vector propeller,respectively.The hydrodynamic forces obtained from the simulation are consistent with data measured by a force sensor,proving the credibility of the simulated hydrodynamics.Subsequently,by applying the results of the hydrodynamic force in this study,the flapping trajectory of the wingtip is planned using the cubic spline interpolation method.Furthermore,two underwater demo vehicles with a pair of CWMs are developed,and experiments are conducted in a water tank,further validating and demonstrating the feasibility of the proposed CWM.

关键词： controllable wing mechanism hybrid-driven underwater glider bioinspired design multi-locomotion modes

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Structural biology of SARS-CoV-2:open the door for novel therapies

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Signal Transduction and Targeted Therapy 2022年第2期7卷 423-450页

作者： Weizhu Yan yanhui Zheng Xiaotao Zeng Bin He Wei cheng Division of Respiratory and Critical Care Medicine Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular NetworkState Key Laboratory of BiotherapyWest China Hospital of Sichuan University610041 ChengduChina Department of Emergency Medicine West China Hospital of Sichuan University610041 ChengduChina The First People’s Hospital of Longquanyi District chengdu 610100 ChengduChina

Severe Acute Respiratory Syndrome Coronavirus-2(SARS-CoV-2)is the causative agent of the pandemic disease COVID-19,which is so far without efficacious treatment.The discovery of therapy reagents for treating COVID-19 are urgently needed,and the structures of the potential drug-target proteins in the viral life cycle are particularly important.SARS-CoV-2,a member of the Orthocoronavirinae subfamily containing the largest RNA genome,encodes 29 proteins including nonstructural,structural and accessory proteins which are involved in viral adsorption,entry and uncoating,nucleic acid replication and transcription,assembly and release,etc.These proteins individually act as a partner of the replication machinery or involved in forming the complexes with host cellular factors to participate in the essential physiological activities.This review summarizes the representative structures and typically potential therapy agents that target SARS-CoV-2 or some critical proteins for viral pathogenesis,providing insights into the mechanisms underlying viral infection,prevention of infection,and treatment.Indeed,these studies open the door for COVID therapies,leading to ways to prevent and treat COVID-19,especially,treatment of the disease caused by the viral variants are imperative.

关键词： prevention Acute typically

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A Population-Membrane-System-Inspired Evolutionary Algorithm for Distribution Network Reconfiguration

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Chinese Journal of Electronics 2014年第3期23卷 437-441页

作者： ZHANG Gexiang RONG Haina cheng Jixiang QIN yanhui School of Electrical Engineering Southwest Jiaotong University

This paper proposes a Populationmembrane-system-inspired evolutionary algorithm(PMSIEA), which is designed by using a population P system and a Quantum-inspired evolutionary algorithm(QIEA). PMSIEA uses the population P system with three cells to organize three variants of QIEAs, where communications between cells are performed at the level of genes,instead of the level of individuals reported in the existing membrane algorithms. This work provides a useful framework for synthesizing different algorithms at macro level and exchanging genic information at micro scale. Experimental results conduced on knapsack problems show that PMSIEA is superior to four representative QIEAs and our previous work with respect to the quality of solutions and the elapsed time. We also use PMSIEA to solve the optimal distribution system reconfiguration problem in power systems for minimizing the power loss.

关键词： Membrane computing Membrane-inspired evolutionary algorithm Population P system Distribution system reconfiguration

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Epidemiological and Virological Surveillance of Seasonal Influenza Viruses—China,2020–2021

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China CDC weekly 2021年第44期3卷 918-922页

作者： Weijuan Huang Xiyan Li Minju Tan Yanhui Cheng Tao Chen Hejiang Wei Xiaoxu Zeng Yiran Xie Jia Liu Ning Xiao Lei Yang Dayan Wang National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionWHO Collaborating Centre for Reference and Research on InfluenzaKey Laboratory for Medical VirologyNational Health CommissionBeijingChina

Introduction:During the coronavirus disease 2019(COVID-19)pandemic,the circulation of seasonal influenza virus declined globally and remained below previous seasonal levels.We analyzed the results of the epidemiology,antigenic,and genetic characteristics,and antiviral susceptibilities of seasonal influenza viruses isolated from the mainland of China during October 5,2020 through September 5,2021,to better assess the risk of influenza during subsequent influenza season in 2021–2022.Methods:Positive rates of influenza virus detection during this period were based on real-time polymerase chain reaction(PCR)detection by the Chinese National Influenza Surveillance Network laboratories,and isolated viruses from influenza positive samples were submitted to the Chinese National Influenza Center.Antigenic analyses for influenza viruses were conducted using the hemagglutination inhibition assay.Next-generation sequencing was used for genetic analyses.Viruses were tested for resistance to antiviral medications using a phenotypic assay and next-generation sequencing.Results:In southern China,the influenza positivity rate was elevated especially after March 2021 and was higher than the same period the previous year with the COVID-19 pandemic.In northern China,influenza positive rate peaked at Week 18 in 2021 and has declined since then.Nearly all isolated viruses were B/Victoria lineage viruses during the study period,and 37.3%of these viruses are antigenically similar to the reference viruses representing the vaccine components for the 2020–2021 and 2021–2022 Northern Hemisphere influenza season.All seasonal influenza viruses were susceptible to neuraminidase inhibitors and endonuclease inhibitors.Conclusions:Influenza activity has gradually increased in the mainland of China in 2021,although the intensity of activity is still lower than before the COVID-19 pandemic.The diversity of circulating influenza types/subtypes decreased,with the vast majority being B/Victoria lineage viruses.The surveillance data from this study sug

关键词： mainland season prevention

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Characterization of Influenza Viruses-China, 2019−2020

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China CDC weekly 2020年第44期2卷 856-861页

作者： Weijuan Huang Yanhui Cheng Tao Chen Xiyan Li Minju Tan Hejiang Wei Xiaoxu Zeng Yiran Xie Jia Liu Ning Xiao Lei Yang Dayan Wang National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionWHO Collaborating Center for Reference and Research on InfluenzaKey Laboratory for Medical VirologyNational Health CommissionBeijingChina

Introduction:Influenza surveillance is necessary for detection of emerging variants of influenza viruses and determining their epidemiological and clinical significance.Vaccination and antiviral drugs remain the most useful ways to protect against seasonal influenza and its potentially severe consequences.This study describes the epidemiology,antigenic and genetic characteristics,and antiviral susceptibilities of influenza viruses isolated from the mainland of China during the April 1,2019 through October 4,2020.Methods:All viruses analyzed were isolated and submitted by Chinese National Influenza Surveillance Network laboratories.The Chinese National Influenza Center performed antigenic analysis,sequencing,and antiviral resistance testing after propagation of the viruses.Antigenic characterizations were determined by hemagglutinin inhibition assay;next-generation sequencing was used for genetic analyses;phenotypic assay and next-generation sequencing were used for determining antiviral resistance.Results:The influenza positivity rate declined significantly starting in late January 2020 and has remained low.There was no summer influenza peak season in south China.Influenza A(H3N2)and B/Victoria lineage viruses were the dominant subtype/lineage during April 1,2019 through October 4,2020.The majority of influenza viruses were antigenically and genetically similar to reference viruses representing components of vaccines for the 2020–2021 northern hemisphere influenza season.Nearly all seasonal influenza viruses were susceptible to oseltamivir and zanamivir.Conclusions and Implications for Public Health Practice:Since the outbreak of COVID-19,the influenza positivity rate declined with implementation of strong COVID-19 control measures.The majority of circulating viruses are well matched with the current 2020–2021 northern hemisphere influenza vaccine viruses.Circulating seasonal influenza viruses were sensitive to neuraminidase inhibitors and Baloxavir marboxil.This study provided evidence for World Health Organizat

关键词： epidemiology prevention mainland

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基于支路模型的交直流混合配电网统一潮流计算

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电网技术 2023年第10期47卷 4302-4310页

作者：李国庆赵妍辉成龙现代电力系统仿真控制与绿色电能新技术教育部重点实验室(东北电力大学) 吉林省吉林市132012

交直流混合配电网潮流计算是交直流混合配电网规划和运行调控策略设计的重要基础。为实现对高比例电力电子设备集成的复杂混合配电网的精确潮流计算,提高潮流模型的统一性和普适性,提出基于支路模型的交直流混合配电网统一潮流计算方法... 详细信息

交直流混合配电网潮流计算是交直流混合配电网规划和运行调控策略设计的重要基础。为实现对高比例电力电子设备集成的复杂混合配电网的精确潮流计算,提高潮流模型的统一性和普适性,提出基于支路模型的交直流混合配电网统一潮流计算方法。首先,对混合网络中包含的电压源型变流器(voltage source converter,VSC)和DC/DC变换器的稳态模型进行了详细分析。然后,建立不同场景下任意节点间可能接线方案的支路潮流模型。在此基础上,通过拓展定义网络矩阵,建立混合配电网统一功率平衡方程。进而,根据雅克比矩阵修正,基于牛顿–拉夫逊算法对变流器不同控制方式下的交直流混合配电网潮流进行求解。最后,通过算例分析,并将潮流计算结果与电磁仿真结果进行对比,验证了所提潮流计算模型的正确性和灵活性,并通过改变配电线路R/X比和负荷功率验证了该潮流算法的鲁棒性。

关键词：交直流混合配电网网络矩阵 DC/DC变换器支路潮流模型控制策略潮流计算

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Clinical feature and waveform in infantile nystagmus syndrome in children with FRMD7 gene mutations

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Science China(Life Sciences) 2017年第7期60卷 707-713页

作者： Dayong Bai Wei Shi Zhan Qi Wei Li Aihua Wei yanhui Cui cheng Li Li Li Department of Ophthalmology Beijing Children's Hospital Capital Medical UniversityNational Center for Children's Health Beijing Pediatric Research Institute Beijing Children's Hospital Capital Medical UniversityNational Center for Children's Health Department of Dermatology Beijing Tongren Hospital Capital Medical University

Infant nystagmus sydrome presents as involuntary eye movement disorder and can affect seriously ocular function. We performed a retrospective study of clinical data and FRMD7 genetic test results in 12 cases of infantile nystagmus syndrome to correlate waveform, stereopsis, and visual acuity. The patients(age 6.40±2.67 years) had FRMD7 mutations as follows: missense in eight cases, shear in two cases, frameshift in one case, and non-frameshift in one case. Horizontal jerk waveform was observed in six cases, versus horizontal pendulum in five cases and dual jerk in one case. The uncorrected visual acuity(24 eyes) was 0.21±0.12,compared with a corrected visual acuity(24 eyes) of 0.32±0.14. All patients had simultaneous perception, versus fusion function in 10 cases(83.33%) and stereoscopic vision in seven cases(58.33%) using the synoptophore. Eleven cases(91.67%) detected the stereo fly, compared with five cases(41.67%) for stereoscopic circles and seven cases(58.33%) for stereoscopic animals by Titmus test. Stereoscopic vision using the synoptophore did not correlate with the frequency, amplitude, or intensity of nystagmus or with corrected binocular visual acuity. The infantile nystagmus syndrome with FRMD7 mutations in our cases was caused primarily de novo and missense mutations. Visual acuity and binocular visual function were significant impaired, and the waveform was generally horizontal jerk. Also, an infrared videonystagmogram can record the frequency, amplitude, and intensity of nystagmus accurately.

关键词：基因突变临床资料综合征震颤眼球婴儿致病波形

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