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Wind turbine clutter mitigation using morphological component analysis with group sparsity

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Journal of Systems Engineering and Electronics 2023年第3期34卷 714-722页

作者： wan xiaoyu SHEN Mingwei WU Di ZHU Daiyin College of Computer and Information Hohai UniversityNanjing 211100China Key Laboratory of Radar Imaging and Microwave Photonics&Ministry of Education Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To address the problem that dynamic wind turbine clutter(WTC)significantly degrades the performance of weather radar,a WTC mitigation algorithm using morphological component analysis(MCA)with group sparsity is studied in this paper.The ground clutter is suppressed firstly to reduce the morphological compositions of radar echo.After that,the MCA algorithm is applied and the window used in the short-time Fourier transform(STFT)is optimized to lessen the spectrum leakage of WTC.Finally,the group sparsity structure of WTC in the STFT domain can be utilized to decrease the degrees of freedom in the solution,thus contributing to better estimation performance of weather signals.The effectiveness and feasibility of the proposed method are demonstrated by numerical simulations.

关键词： weather radar wind turbine clutter(WTC) morphological component analysis(MCA) short-time Fourier transform(STFT) group sparsity

Transient Stability Preventive Control of Wind Farm Connected Power System Considering the Uncertainty

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Energy Engineering 2024年第6期121卷 1637-1656页

作者： Yuping Bian Xiu wan xiaoyu Zhou School of Electric Power Engineering Nanjing Institute of TechnologyNanjing211167China

To address uncertainty as well as transient stability constraints simultaneously in the preventive control of windfarm systems, a novel three-stage optimization strategy is established in this paper. In the first stage, the probabilisticmulti-objective particle swarm optimization based on the point estimate method is employed to cope with thestochastic factors. The transient security region of the system is accurately ensured by the interior point methodin the second stage. Finally, the verification of the final optimal objectives and satisfied constraints are enforcedin the last stage. Furthermore, the proposed strategy is a general framework that can combine other optimizationalgorithms. The proposed methodology is tested on the modified WSCC 9-bus system and the New England 39-bussystem. The results verify the feasibility of the method.

关键词： Transient preventive control chance-constrained programming multi-objective PSO TSCOPF wind farm

Oxygen vacancies confined in porous Co_(3)V_(2)O_(8)sheets for durable and high-energy aqueous sodium-ion capacitors

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Nano Research 2022年第6期15卷 5123-5133页

作者： Anchun Tang Chubin wan Xianhe Meng Xiangcao Li xiaoyu Hu Miaofeng Huang Xin Ju Physics Department University of Science and TechnologyBeijing 100083China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China College of Science Xi’an Aeronautical UniversityXi’an 710077China

Sodium-ion capacitors have the potential to deliver high energy,power density,and excellent cycling stability.In this study,ultrathin Co_(3)V_(2)O_(8)nanosheets are successfully synthesized through an one-pot hydrothermal reaction and a subsequent doping reconfiguration-induced vacancy-forming process.Abundant oxygen vacancies and high porosity are observed in the Co_(3)V_(2)O_(8)electrode and result in excellent electrochemical performance in 1 M NaOH and Na_(2)SO_(4)electrolytes.The cathode has a large specific capacity(@NaOH),high-rate capability(@NaOH),wide voltage window(@Na_(2)SO_(4)),and favorable long-cycle stability.Ex-situ X-ray diffraction and X-ray photoelectron spectroscopy show that the Co_(3)V_(2)O_(8)electrode displays a battery-like behavior related to OH−ions in the alkaline NaOH electrolyte.By contrast,in the neutral Na_(2)SO_(4)electrolyte,Co_(3)V_(2)O_(8)mainly shows an intercalation/extraction behavior with Na+ions.Density functional theory calculation suggests that oxygen vacancy leads to a new state located in the bandgap,which greatly improves the electron transfer efficiency and reduces the sodiation energy barrier of Co_(3)V_(2)O_(8)in the neutral Na_(2)SO_(4)electrolyte.Moreover,when paired with a high-voltage activated carbon(AC)anode,full-cell Co_(3)V_(2)O_(8)//Na_(2)SO_(4)//AC delivers high energy/power densities(89.6 Wh·kg^(−1)/330 W·kg^(−1)).

关键词： mesoporous Co_(3)V_(2)O_(8) oxygen vacancy aqueous hybrid capacitors sodium ion storage electrochemical mechanism

Transdermal delivery of Chinese herbal medicine extract using dissolvable microneedles for hypertrophic scar treatment

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Acta Pharmaceutica Sinica B 2021年第9期11卷 2937-2944页

作者： xiaoyu Ning Christian Wiraja wan Ting Sharon Chewa Chen Fan Chenjie Xu NTU Institute for Health Technologies Interdisciplinary Graduate GroupNanyang Technological UniversitySingapore 639798Singapore School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore 637459Singapore Skin Research Institute of Singapore 8A Biomedical GroveSingapore 138648Singapore Department of Biomedical Engineering City University of Hong KongHong Kong SAR 999077China

Hypertrophic scars are unfavorable skin diseases characterized by excessive collagen deposition.Although systemic treatments exist in clinic to manage hypertrophic scars,they pose significant side effects and tend to lose efficacy over prolonged applications.Traditional Chinese medicine(TCM)offers as a promising candidate to treat pathological scars.A large number of TCMs have been studied to show anti-scarring effect,however,the natural barrier of the skin impedes their penetration,lowering its therapeutic efficacy.Herein,we reported the use of dissolvable hyaluronic acid(HA)microneedles(MNs)as a vehicle to aid the transdermal delivery of therapeutic agent,a model TCM called shikonin for the treatment of hypertrophic scars.Here,shikonin was mixed with HA to make MNs with adequate mechanical strength for skin penetration,making its dosage controllable during the fabrication process.The therapeutic effect of the shikonin MNs was studied in vira using HSFs and then further verified with quantitative reverse transcriptase polymerase chain reaction.Our data suggest that the shikonin HA MNs significantly reduce the viability and proliferation of the HSFs and downregulate the fibrotic-related genes(i.e.,TGFβ1,FAP-αand COL1 A1).Furthermore,we observed a localized therapeutic effect of the shikonin HA MNs that is beneficial for site-specific treatment.

关键词： Traditional Chinese medicine Shikonin Hyaluronic acid Microneedle Hypertrophic scarring Drug delivery Transdermal delivery Skin

Wave Azimuth Cutoff Compensation Method and the Multisatellite Networking Mode of SAR

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Journal of Ocean University of China 2023年第3期22卷 683-696页

作者： wan Yong CUI Kun QU Ruozhao DAI Yongshou LI Ligang QU Xiaojun ZHANG xiaoyu College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China China College of Control Science and Engineering China University of PetroleumQingdao 266580China

Synthetic aperture radars(SARs)encounter the azimuth cutoff problem when observing sea waves.Consequently,SARs can only capture the waves with wavelengths larger than the cutoff wavelength and lose the information of waves with smaller wavelengths.To increase the accuracy of SAR wave observations,this paper investigates an azimuth cutoff compensation method based on the simulated multiview SAR wave synchronization data obtained by the collaborative observation via networked satellites.Based on the simulated data and the equivalent multiview measured data from Sentinel-1 virtual networking,the method is verified and the cutoff wavelengths decrease by 16.40%and 14.00%.The biases of the inversion significant wave height with true values decrease by 0.04 m and 0.14 m,and the biases of the mean wave period decrease by 0.17 s and 0.22 s,respectively.These results demonstrate the effectiveness of the azimuth cutoff compensation method.Based on the azimuth cutoff compensation method,the multisatellite SAR networking mode for wave observations are discussed.The highest compensation effect is obtained when the combination of azimuth angle is(95°,115°,135°),the orbital intersection angle is(50°,50°),and three or four satellites are used.The study of the multisatellite networking mode in this paper can provide valuable references for the compensation of azimuth cutoff and the observation of waves by a multisatellite network.

关键词： synthetic aperture radar(SAR) compensation effect cutoff wavelength multisatellite networking mode

OStme: Online consensus survival analysis web server for tumor microenvironment components of pan-cancers

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Genes & Diseases 2023年第6期10卷 2256-2259页

作者： Longxiang Xie Qiang wang xiaoyu Ma Guo Zhao Zhongyi Yan Huimin Li wan Zhu Zhanjie Zuo Xiangqian Guo Department of Preventive Medicine Institute of Biomedical InformaticsBioinformatics CenterHenan Provincial Engineering Center for Tumor Molecular MedicineAcademy for Advanced Interdisciplinary StudiesSchool of SoftwareSchool of Basic Medical SciencesHenan UniversityKaifengHenan 475004China Department of Anesthesia Stanford UniversityStanfordCA 94305United States Thoracic Cancer Treatment Center Armed Police Beijing Corps HospitalBeijing 100027China

Tumor microenvironment(TME)is the environment around the tumor cells,consisting of extracellular matrix,nonmalignant stromal cells,and various types of immune cells(like macrophages,B and T lymphocytes).1 TME has been recurrently reported to play important roles in the progression of cancers.1 The mechanism study of TME may offer opportunities for targeted/immune therapies.However,how TME components impact the prognosis of cancer patients remains to be determined.

关键词： cancers microenvironment prognosis

Engineering single atomic ruthenium on defective nickel vanadium layered double hydroxide for highly efficient hydrogen evolution

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Nano Research 2023年第4期16卷 4612-4619页

作者： xiaoyu Chen Jiawei wan Meng Zheng Jin wang Qinghua Zhang Lin Gu Lirong Zheng Xianzhu Fu Ranbo Yu College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science and Technology Beijing InstitutionBeijing 100083China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Advanced Material Processing&Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002China

Fabricating single-atom catalysts(SACs)with high catalytic activity as well as great stability is a big challenge.Herein,we propose a precise synthesis strategy to stabilize single atomic ruthenium through regulating vanadium defects of nickel vanadium layered double hydroxides(NiV-LDH)ultrathin nanoribbons support.Correspondingly,the isolated atomically Ru doped NiV-LDH ultrathin nanoribbons(NiVRu-R)were successfully fabricated with a super-high Ru load of 12.8 wt.%.X-ray absorption spectrum(XAS)characterization further confirmed atomic dispersion of Ru.As catalysts for electrocatalytic hydrogen evolution reaction(HER)in alkaline media,the NiVRu-R demonstrated superior catalytic properties to the commercial Pt/C.Moreover,it maintained exceptional stability even after 5,000 cyclic voltammetry cycles.In-situ XAS and density functional theory(DFT)calculations prove that the Ru atomic sites are stabilized on supports through forming the Ru-O-V structure,which also help promote the catalytic properties through reducing the energy barrier on atomic Ru catalytic sites.

关键词： hydrogen evolution reaction layered double hydroxide ruthenium atomic site ultrathin nanoribbons

Influence of laser shock peening on surface integrity and tensile property of high strength low alloy steel

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Chinese Journal of Aeronautics 2021年第6期34卷 199-208页

作者： Yong wanG xiaoyu PAN Xibin wanG Zhibing LIU Shuyao LIU Wenjuan wan Puyi wanG School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Laser Shock Peening(LSP)is a well-established surface treatment commonly used to improve mechanical properties of material’s surfaces.To further understand the relationship between tensile property and fatigue life improvement of high strength low alloy steel in the LSP process,LSP treatment of 32 CrNi high strength low alloy steel was carried out by YAG laser with pulse energy of 15 J,and tensile property was tested by electronic universal material testing machine.Surface morphology,residual stress and tensile fracture of the specimens before and after LSP were observed by white light interferometer(WLI),X-ray measuring apparatus and scanning electron microscope(SEM).Result shows that LSP did not change tensile strength of 32 CrNi steel but cause yield characteristic transform from obvious yield point to no yield phenomenon which is the only factor benefiting fatigue life,indicating that the increment of fatigue life was probably related to the disappearance of yield phenomenon.Formation mechanisms of tensile fractures and yield phenomenon induced by LSP at room temperature were also discussed and completely revealed.Deeper compressive residual stress and flat grains contributed to the transition of yield characteristic and lower elongation rate of 32 CrNi steel subjected to LSP.

关键词： 32CrNi steel Laser shock peening Residual stress Tensile property Yield characteristic

Metal-organic framework-derived Ni/ZnO nano-sponges with delicate surface vacancies as anode materials for high-performance supercapacitors

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Nano Research 2021年第11期14卷 4063-4072页

作者： Anchun Tang Chubin wan xiaoyu Hu Xin Ju School of Mathematics and Physics University of Science and Technology BeijingBeijing100083China

Ni/ZnO nano-sponges have been successfully synthesized through optimized annealing of Ni/Zn-based organic framework (Ni/Zn-MOF). The annealed MOF provides the stable carbon structure with 3D interconnection and prevents structural collapse during the charging and discharging process. The annealing causes the incorporation of intrinsic Ni^(3+) in the surface of NiO nanoparticles, providing more reaction active sites. The oxygen vacancies in ZnO and heterostructure interfaces between NiO and ZnO promote the charge transformation. Based on the aforementioned advantages, the Ni/ZnO nanocomposites exhibit excellent electrocatalytic performances for supercapacitors. The specific capacitance can reach to 807 F·g^(−1) at 1 A·g^(−1) in the studied electrodes. After 5,000 cycles at 10 A·g^(−1), the cyclic stability remains excellent at 86% of the initial capacitance. Moreover, the as-prepared asymmetric supercapacitor exhibits a high energy density of 30.6 W·h·kg^(−1) at power density of 398 W·kg^(−1). This study is expected to provide new insights into exploring the potential mechanism of catalyst action.

关键词： metal-organic frameworks ZnO-based nano-sponges surface vacancies supercapacitor electrochemical performance