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A Subdivision-Based Combined Shape and Topology Optimization in Acoustics

Computer Modeling in Engineering & Sciences 2024年第4期139卷 847-872页

作者： Chuang Lu Leilei Chen Jinling Luo haibo Chen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei230027China College of Intelligent Construction Wuchang University of TechnologyWuhan430223China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation School of Architecture and EngineeringHuanghuai UniversityZhumadian463000China Beijing Aerospace Technology Institute Beijing100074China

We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision *** existing structural optimization methods mainly contain shape and topology schemes,with the former changing the surface geometric profile of the structure and the latter changing thematerial distribution topology or hole topology of the *** the present acoustic performance optimization,the coordinates of the control points in the subdivision surfaces fine mesh are selected as the shape design parameters of the structure,the artificial density of the sound absorbing material covered on the structure surface is set as the topology design parameter,and the combined topology and shape optimization approach is established through the sound field analysis of the subdivision surfaces boundary element method as a *** topology and shape sensitivities of the approach are calculated using the adjoint variable method,which ensures the efficiency of the *** geometric jaggedness and material distribution discontinuities that appear in the optimization process are overcome to a certain degree by the multiresolution method and solid isotropic material with *** examples are given to validate the effectiveness of the presented optimization approach.

关键词： Subdivision surfaces boundary element method topology optimization shape optimization combined optimization

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Local saliency consistency-based label inference for weakly supervised salient object detection using scribble annotations

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 239-249页

作者： Shuo Zhao Peng Cui Jing Shen haibo Liu School of Computer Science and Technology Harbin University of Science and TechnologyHarbinChina School of Computer Science and Technology Harbin Engineering UniversityHarbinChina

Recently,weak supervision has received growing attention in the field of salient object detection due to the convenience of ***,there is a large performance gap between weakly supervised and fully supervised salient object detectors because the scribble annotation can only provide very limited foreground/background ***,an intuitive idea is to infer annotations that cover more complete object and background regions for *** this end,a label inference strategy is proposed based on the assumption that pixels with similar colours and close positions should have consistent ***,k-means clustering algorithm was first performed on both colours and coordinates of original annotations,and then assigned the same labels to points having similar colours with colour cluster centres and near coordinate cluster ***,the same annotations for pixels with similar colours within each kernel neighbourhood was set *** experiments on six benchmarks demonstrate that our method can significantly improve the performance and achieve the state-of-the-art results.

关键词： label inference salient object detection weak supervision

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A Time Series Short-Term Prediction Method Based on Multi-Granularity Event Matching and Alignment

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Computers, Materials & Continua 2024年第1期78卷 653-676页

作者： haibo Li Yongbo Yu Zhenbo Zhao Xiaokang Tang College of Computer Science and Technology Huaqiao UniversityXiamen361021China

Accurate forecasting of time series is crucial across various *** prediction tasks rely on effectively segmenting,matching,and time series data *** instance,regardless of time series with the same granularity,segmenting them into different granularity events can effectively mitigate the impact of varying time scales on prediction ***,these events of varying granularity frequently intersect with each other,which may possess unequal *** minor differences can result in significant errors when matching time series with future ***,directly using matched events but unaligned events as state vectors in machine learning-based prediction models can lead to insufficient prediction ***,this paper proposes a short-term forecasting method for time series based on a multi-granularity event,MGE-SP(multi-granularity event-based short-termprediction).First,amethodological framework for MGE-SP established guides the implementation *** framework consists of three key steps,including multi-granularity event matching based on the LTF(latest time first)strategy,multi-granularity event alignment using a piecewise aggregate approximation based on the compression ratio,and a short-term prediction model based on *** data from a nationwide online car-hailing service in China ensures the method’s *** average RMSE(root mean square error)and MAE(mean absolute error)of the proposed method are 3.204 and 2.360,lower than the respective values of 4.056 and 3.101 obtained using theARIMA(autoregressive integratedmoving average)method,as well as the values of 4.278 and 2.994 obtained using k-means-SVR(support vector regression)*** other experiment is conducted on stock data froma public data *** proposed method achieved an average RMSE and MAE of 0.836 and 0.696,lower than the respective values of 1.019 and 0.844 obtained using the ARIMA method,as well as the values of 1.350 and 1.172 obtained usin

关键词： Time series short-term prediction multi-granularity event alignment event matching

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Eutrophication of Jiangsu Coastal Water and Its Role in the Formation of Green Tide

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Journal of Ocean University of China 2024年第1期23卷 109-118页

作者： XIAO Mingyan SONG Weina ZHANG haibo SHI Xiaoyong SU Rongguo Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China National Marine Environmental Monitoring Center Dalian 116000China National Marine Hazard Mitigation Service Beijing 100194China

Since 2007,the large-scale green tide caused by Ulva prolifera(***)have occurred as a recurrent phenomenon in the southern Yellow Sea of *** surveys and satellite remote sensing showed that the small scattered patches of green tide algae were first observed along the Porphyra agriculture area of the Subei Shoal in late *** this study,we attempted to identify the role of eutrophication in the origin of the green tide in the Subei Shoal and its adjacent *** Shoal and its adjacent area are characterized by rich nutrients,especially NO_(3)^(-)-N,NH_(4)^(+)-N,PO_(4)^(3-)-P,and other bioavailable components(such as urea-N and amino acids).In the spring of 2017,the average concentrations of NO_(3)^(-)-N were 19.01±11.01μmolL^(-1),accounting for 86.68%of the dis-solved inorganic nitrogen(DIN).In addition,the average concentration of NH4^(+)-N was 2.51±1.60μmolL^(-1).PO_(4)^(3-)-P had an average concentration of 0.14±0.13μ*** average concentrations of urea-N and total hydrolyzed amino acids(THAA)were 1.73±1.36μmolL^(-1)and 1.33±0.80μmolL^(-1),*** nutritive substances play a key role in the rapid production of *** and make the Jiangsu coastal water an incubator for green tide.

关键词： green tide nutrients algae Ulva prolifera eutrophication Subei Shoal

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Effect of intermittent joint distribution on the mechanical and acoustic behavior of rock masses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1231-1244页

作者： Shuaiyang Fu haibo Li Liwang Liu Di Wu Ben Wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic *** this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were *** results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the *** uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number ***,the wave velocity grows monotonically as the joint dip angle *** the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip *** wave velocity parallel to the joints is greater than that perpendicular to the *** the dip angle of joints remains unchanged,the UCS and wave velocity are positively *** the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity *** reveal the effect of the joint distribution on the velocity,a theoretical model was also *** to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation ***,a theoretical indicator(*** tensor)was adopted to analyze the variation of the wave velocity and UCS.

关键词： Stochastic joints Intrinsic cohesive zone model Uniaxial compressive strength(UCS) Wave propagation Fabric tensor

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Pr-Tb synergistic strengthening on coercivity of Nd-Ce-Fe-B magnets grain boundary diffused with Pr-Tb-Al-Ga alloys

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Journal of Rare Earths 2024年第9期42卷 1704-1709页

作者： Ruifang Song Hang Zhao haibo Feng Institute of Functional Materials Central Iron & Steel Research Institute

Sintered Nd-Ce-Fe-B magnets were grain boundary diffused（GBDed） with PrxTb80-xAl10Ga10（at%）(x=0,20,40,60,80) *** effect of Pr/Tb content in diffusion source on magnetic properties,microstructure and elements distribution of GBDed magnets was *** Pr is used to substitute for 75% Tb in diffusion source,Tb consumption per unit coercivity improvement of GBDed magnet reduces by 77%,compared with the Tb80Al10Ga10diffused *** element diffuses into magnets and then forms Tb-rich shell with high magneto-crystalline anisotropy field surrounding main phase grains,resulting in substantial coercivity *** with low melting point diffuses deeply along liquid grain boundary phase during GBD *** can eliminate some sharp defects of main phase grains and make grain boundaries smooth,which provides diffusion channels for further diffusion of Tb ***,there are more diffusion channels for Tb and less Tb enriched at surface region,making Tb diffuse more deeply and improving Tb utilization *** method significantly improves the coercivity,and realizes the green,efficient and high-quality utilization of heavy rare earth（HRE）elements.

关键词： Grain boundary diffusion Rare earths Microstructure Synergistic strengthening

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MXene:Promising materials for magnesium-ion batteries

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Chinese Journal of Chemical Engineering 2024年第5期69卷 199-211页

作者： Liuyu Song haibo Li Pengkai Wang Yu Shang Yue Yang Zhaoyu Wu School of Resources and Civil Engineering Northeastern UniversityShenyang 110004China

Magnesium-ion batteries(MIBs)have attracted extensive attention due to their high theoretical capacity,superior safety,and low ***,the development of MIBs is hindered by the lack of cathode materials with long cycle life and rate *** stands out as a prime choice for MIB cathode or collector for anode-free magnesium batteries(AFMBs)because of its larger surface area,adjustable surface properties,and good electrical *** this paper,we summarized the preparation and layering methods of MXene and discussed the prospects of MXene as a cathode or collector for *** review will be immensely beneficial in critically analyzing the synthesis techniques and the applications of MXene material as MIB cathode or AFMB *** addition,the challenges of the preparation and layering were concluded,along with raising the research strategies of MXene for storing Mg ions.

关键词： MXene Nanomaterials Electrochemistry Optimization Magnesium-ion batteries(MIBs)

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航空用负压方舱环境检测仪的研制

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中国医学装备 2024年第8期21卷 187-189页

作者：雍伟张慕哲李法林周海亮姜媛媛薛兵杰田甜江妍杜海波郭磊江琅空军军医大学空军特色医学中心研究部航空救生研究室北京100142

为在航空转运过程中检测机载负压隔离方舱的环境数据,研制一款航空用负压方舱环境检测仪,由壳体、差压变送器、压力传感器、二氧化碳浓度传感器、氧气浓度传感器、温湿度传感器、数据处理模块、液晶显示屏与通用串行总线(USB)数据接口... 详细信息

为在航空转运过程中检测机载负压隔离方舱的环境数据,研制一款航空用负压方舱环境检测仪,由壳体、差压变送器、压力传感器、二氧化碳浓度传感器、氧气浓度传感器、温湿度传感器、数据处理模块、液晶显示屏与通用串行总线(USB)数据接口等部件组成负压方舱环境检测仪,可实时检测二氧化碳浓度、氧气浓度、温度、相对湿度、舱内与舱外压差和舱外气压等环境数据,数据处理模块收集数据处理后,由液晶显示屏实时显示数据与数据变化曲线,并通过USB数据接口提取检测数据。在航空环境使用时,该检测仪可无故障连续工作时间≥300 h,故障平均修复时间约为30 min,性能良好,检测精度较高,可为负压方舱的环境数据检测提供便利。

关键词：负压舱环境检测压差温湿度

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Design methodology,synthesis,and control strategy of the high-speed planetary rover

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Frontiers of Mechanical Engineering 2024年第2期19卷 59-74页

作者： Renchao LU haibo GAO Zhen LIU Runze YUAN Zongquan DENG State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

The planned missions to explore the surfaces of the Moon and Mars require high exploration efficiency,thus imposing new demands on the mobility system of planetary *** this paper,a design method for a high-speed planetary rover(HPR)is proposed,and the representative configurations are modeled and ***,the influence of the planetary surface environment on the design of HPRs is analyzed,and the design factors for HPRs are determined by studying a single-wheel ***,a design methodology for HPRs is *** adaptive suspension mechanisms of a four-wheeled rover are synthesized using the all-wheel-attachment condition and position and orientation characteristics theory,which are expressed in the form of a graph theory for the increase in elastic components and active ***,a dynamic model is built,and a simulation is carried out for the proposed *** validity of the proposed method and rover is verified,thus highlighting their potential application in future planetary exploration.

关键词： design methodology spectrum analysis high-speed planetary rover type synthesis

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Hierarchical porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy ceramics prepared by a self-foaming method for thermal insulation

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Journal of Advanced Ceramics 2024年第7期13卷 956-966页

作者： Cuiyan Li Ruinan Gao haibo Ouyang Tianzhan Shen Zihao Chen Yanlei Li Key Laboratory for Green Manufacturing&Functional Application of Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi’an 710021China

To meet the emerging demands for thermal protection materials for hypersonic aircraft,developing porous ultrahigh-temperature ceramics with both robust mechanical properties and superior thermal insulation performance is a critical ***,we report novel porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy carbide(PHEC)ceramics fabricated by a self-foaming method using commercially available metal chloride and furfuryl alcohol(FA)as *** PHEC ceramics are constructed of microspheres with a size of 2µm,leading to a high porosity of 91.3%and an interconnected *** microspheres consist of high-entropy carbide grains(20 nm),resulting in abundant interfaces and nanosized pores in the PHEC *** to its unique hierarchical structure,the prepared PHEC ceramics have outstanding compressive strength(28.1±2 MPa)and exceptionally low thermal conductivity(κT,0.046 W·m^(-1)·K^(-1))at room *** makes it a promising thermal insulation materials for ultrahigh temperature *** work provides a cost-effective and facile strategy for producing porous ultrahigh-temperature ceramics.

关键词： porous ceramics high-entropy carbides hierarchical structure thermal insulation self-foaming

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