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Ultrastable and ultrasensitive pH-switchable carbon dots with high quantum yield for water quality identification,glucose detection,and two starch-based solid-state fluorescence materials

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Nano Research 2020年第11期13卷 3012-3018页

作者： Daiyong chao Jinxing Chen qing dong Weiwei Wu Desheng qi Shaojun dong College of Chemistry Jilin UniversityChangchun130012China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

It is attractive and encouraging to develop new fluorescent carbon dots(CDs)with excellent optical properties and promising applications ***,highly-efficient green emissive CDs(m-CDs)with a high quantum yield(QY)of 71.7%in water are prepared through a facile solvothermal ***,the m-CDs exhibit excellent fluorescence stability in the pH range of 1–***,the fluorescence intensity of the m-CDs is almost completely quenched as the pH is increased from 9 to *** mechanism of the unique pH-responsive behavior is discussed in detail and a plausible mechanism is *** to the unique pH-responsive behavior,the m-CDs are used as a on-off fluorescent probe for water quality *** combining the reversible pH-ultrasensitive optical properties of the m-CDs in the pH range of 9–10 with the glucose oxidase-mimicking(GOx-mimicking)ability of Au nanoparticles(AuNPs),glucose can be quantitatively ***,two environment-friendly starch-based solid-state fluorescence materials(powder and film)are developed through green preparation routes.

关键词： carbon dot high quantum yield pH-ultrasensitive optical properties water quality identification glucose detection solid-state fluorescence materials

Control allocation for aircraft with input constraints based on improved cuckoo search algorithm

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Defence Technology（防务技术） 2017年第1期13卷 1-5页

作者： Yao LU chao-yang dong qing wang School of Aeronautic Science and Engineering BUAABeijing 100191China School of Automation Science and Electrical Engineering BUAABeijing 100191China

The control allocation problem of aircraft whose control inputs contain integer constraints is investigated. The control allocation problem is described as an integer programming problem and solved by the cuckoo search algorithm. In order to enhance the search capability of the cuckoo search algorithm, the adaptive detection probability and amplification factor are designed. Finally, the control allocation method based on the proposed improved cuckoo search algorithm is applied to the tracking control problem of the innovative control effector aircraft. The comparative simulation results demonstrate the superiority and effectiveness of the proposed improved cuckoo search algorithm in control allocation of aircraft.

关键词： Control allocation Optimization Cuckoo search algorithm Innovative control effector aircraft Tracking

New Rational Interpolation Basis Functions on the Unbounded Intervals and Their Applications

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 453-488页

作者： dong-qin Gu Zhong-qing wang chao Zhang School of Mathematics and Statistics Xuzhou University of TechnologyXuzhouJiangsu 221111China School of Science University of Shanghai for Science and TechnologyShanghai 200093China School of Mathematics and Statistics Jiangsu Normal UniversityXuzhouJiangsu 221116China

Based on the rational system of Legendre rational functions,we construct two set of new interpolation basis functions on the unbounded *** explicit expressions are derived,and fast and stable algorithms are provided for computing the new basis *** applications,new rational collocation methods based on these new basis functions are proposed for solving various second-order differential equations on the unbounded *** experiments illustrate that our new methods are more effective and stable than the existing collocation methods.

关键词： Rational collocation methods Birkhoff interpolation fast and stable algorithms

Analysis and evaluation of electromagnetic vibration and noise in permanent magnet synchronous motor with rotor step skewing

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Science China(Technological Sciences) 2019年第5期62卷 839-848页

作者： dong qichao LIU XinTian qi HongZhong SUN chao wang YanSong School of Mechanical and Automotive Engineering Shanghai University of Engineering Science Guangzhou Automobile Group CO. LTD Automotive Engineering Institute

In this paper, a multi-physics simulation model capable of electromagnetic noise prediction is established, and the effectiveness of the established simulation model in predicting and evaluating electromagnetic noise is verified. Based on the verified motor model, a rotor step skewing model which can affect electromagnetic noise is proposed, and the influence of the skewing angle on electromagnetic noise is investigated in detail. By studying the spectral characteristics of the low-order radial magnetic force which has a great influence on electromagnetic noise, the distribution of electromagnetic noise characteristics of the permanent magnet synchronous motor(PMSM) with or without the rotor step skewing is compared and analyzed. Therefore, it lays a technological foundation for predicting and suppressing the electromagnetic vibration noise of electric vehicle(EV) driving motor in the electromagnetic design.

关键词： PMSM electromagnetic noise step skewing multi-physics simulation model spectrum analysis

Effect of Different Raft Shapes on Hydrodynamic Characteristics of the Attenuator-Type Wave Energy Converter

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China Ocean Engineering 2023年第4期37卷 645-659页

作者： wang Jin wang Shu-qi JIANG qing-dian XU Yun-xin SHI Wei-chao School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgowG40LZUK

A numerical simulation method based on CFD has been established to simulate the fully coupled motion for an atten-uator-type wave energy converter(WEC).Based on this method,a detailed parametric analysis has been conducted to investigate the design of the *** effects of different parameters(wave parameters,structural parameters and PTO parameters)on the hydrodynamic characteristics of the attenuator-type WEC were studied in *** results show that in terms of wave parameters,there is an optimal wave period,which makes the relative pitching angle amplitude of the WEC reach the maximum,and the increase of wave height is conducive to the relative pitching angle amplitude of wave *** different wave conditions,the relative pitch angle of the parallelogram raft device is the *** terms of structural parameters,the parallelogram attenuator-type device has the optimal values in different relative directions,different distances and different apex angle,which makes the relative motion amplitude of the device reach the maximum,and the spacing and the apex angle have influence on the motion frequency of the device,while the relative direction has almost no influence on *** terms of PTO parameters,there is an optimal damping coefficient,which makes the power generation efficiency of the WEC reach the *** research results provide a valuable reference for future research and design of the attenuator-type WEC.

关键词： wave energy converter attenuator-type shape hydrodynamic analysis power generation efficiency

Solitary Wave Simulated by the Water Column Collapsing Method

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China Ocean Engineering 2022年第3期36卷 395-402页

作者： wang Jin dong Chang-ming LIU qing-jun ZUO qi-hua School of Marine Sciemces Nanjing University of Information Science&TechnologyNanjing 210044China Southern Ocean Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Nanjing Xinda Institute of Safety and Emergency Management Nanjing 210044China Nanjing Hydraulic Research Institute Nanjing 210029China

Although solitary waves with large ratio of wave height to water depth are difficult to produce in laboratory settings by traditional wave generating methods,a water column collapsing(WCC)method can be *** study uses the WCC method to produce large solitary waves and through a series of experiments,an empirical equation is developed that considers wave height and water depth in addition to water column height and *** solitary waves are studied through wavelet *** from this analysis demonstrate that the ratios between the initial lab-oratory-generated solitary wave and its theoretical counterpart range from 0.2−*** using the results,a new solitary wave generating law is derived and can be applied to future solitary wave laboratory studies.

关键词： water column collapsing solitary wave wavelet spectrum waveform evolution generating law

Enhancement of comprehensive properties of Nb-Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： Wei Wei qi wang Rui-Run Chen chao-Wen Zheng Yan-qing Su National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

This study examines the microstructure,mechanical properties(with a focus on room-temperature toughness),and oxidation resistance of Ho-doped NbDSi based in-situ *** base alloy consists of the coarse primary Nb_(5)Si_(3)phase and the Nb_(5)Si_(3)+Nbss(Nb solid solution)eutectic *** doping influences the solidification *** the Ho doping is higher than0.2 at%,the alloys transform into eutectic *** can be solid-solved in trace amounts in the Nbss ***,most of Ho forms a stable Ho oxide phase,which alleviates oxygen contamination problem to some ***,the interface separation between Ho oxide and other phases reduces the plastic deformation ***,with 0.4 at%Ho doping,the K_(Q)value is18.03 MPa·m^(1/2),which is 31.1%higher than that of the base *** strength of the Ho-doped alloys does not deteriorate with an increase in ***,the large network-like Ho_(2)O_(3)in the 0.8Ho alloy causes a decrease in toughness and *** addition,the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping,the oxidation mass gain per unit area is 10.16 mg·cm^(2),which is 39.7%lower than that of the base alloy.

关键词： Nb-Si based composites Rare earth elements Ho Microstructure Properties

Microstructure and properties of ultrafine WC-Co-VC cemented carbides with different Co contents

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Rare Metals 2022年第6期41卷 1955-1960页

作者： Kai-HuaShi Ke-chao Zhou Zhi-You Li Xiu-qi Zan Kai-Lin dong qing Jiang State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Precision Parts Department Zigong Cemented Carbide Corporation LimitedZigong 643011China

Ultrafine WC-Co-VC cemented carbides are used extensively in a variety of industrial environments due to their excellent mechanical properties and outstanding wear *** content affects the service performance of the cemented *** the present study,the influ-ences of Co content on microstructure,physical,and mechanical properties were investigated *** WC-Co-VC cemented carbides with Co content varying from 4 wt%and 7 wt%and assistance of VC(0.35 wt%)as inhibitor of WC grain growth were *** physical and mechanical properties were tested and the microstructure characteristics were observed by optical microscope(OM)and scanning electron microscopy(SEM).From the results,it is found that with Co content increasing,both the cobalt magnetism and bending strength increase,while the coercive force,Rockwell hardness,density,and abrasive wear resistance *** addition,the OM and SEM results show that the increase of Co content in WC-Co-VC cemented carbides tends to reduce the quantity and size of micro-pores,and make the fracture mode change from brittle fracture to ductile fracture.

关键词： Ultrafine Cemented carbide Co content Microstructure Properties

SAM-drivenMAE pre-training and background-awaremeta-learning for unsupervised vehicle re-identification

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Computational Visual Media 2024年第4期10卷 771-789页

作者： dong wang qi wang Weidong Min Di Gai qing Han Longfei Li Yuhan Geng School of Software Nanchang UniversityNanchang 330047China School of Mathematics and Computer Science Nanchang UniversityNanchang 330031China Institute of Metaverse Nanchang UniversityNanchang 330031China Jiangxi Key Laboratory of Smart City Nanchang 330031China School of Public Health University of MichiganAnn Arbor 48109USA

Distinguishing identity-unrelated background information from discriminative identity information poses a challenge in unsupervised vehicle re-identification(Re-ID).Re-ID models suffer from varying degrees of background interference caused by continuous scene *** recently proposed segment anything model(SAM)has demonstrated exceptional performance in zero-shot segmentation *** combination of SAM and vehicle Re-ID models can achieve efficient separation of vehicle identity and background *** paper proposes a method that combines SAM-driven mask autoencoder(MAE)pre-training and backgroundaware meta-learning for unsupervised vehicle *** method consists of three ***,the segmentation capacity of SAM is utilized to separate the vehicle identity region from the *** cannot be robustly employed in exceptional situations,such as those with ambiguity or ***,in vehicle Re-ID downstream tasks,a spatiallyconstrained vehicle background segmentation method is presented to obtain accurate background segmentation ***,SAM-driven MAE pre-training utilizes the aforementioned segmentation results to select patches belonging to the vehicle and to mask other patches,allowing MAE to learn identity-sensitive features in a self-supervised ***,we present a background-aware meta-learning method to fit varying degrees of background interference in different scenarios by combining different background region *** experiments demonstrate that the proposed method has state-of-the-art performance in reducing background interference variations.

关键词： unsupervised re-identification(Re-ID) vehicles segmentation autoencoder meta-learning