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Weighted Linear Loss Large Margin Distribution Machine for Pattern Classification

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Chinese Journal of Electronics 2024年第3期33卷 753-765页

作者： Ling LIU maoxiang chu Rongfen GONG Liming LIU Yonghui YANG School of Electronic and Information Engineering University of Science and Technology Liaoning

Compared with support vector machine,large margin distribution machine(LDM) has better generalization performance.The central idea of LDM is to maximize the margin mean and minimize the margin variance simultaneously.But the computational complexity of LDM is high.In order to reduce the computational complexity of LDM,a weighted linear loss LDM(WLLDM) is proposed.The framework of WLLDM is built based on LDM and the weighted linear loss.The weighted linear loss is adopted instead of the hinge loss in WLLDM.This modification can transform the quadratic programming problem into a simple linear equation,resulting in lower computational complexity.Thus,WLLDM has the potential to deal with large-scale datasets.The WLLDM is similar in principle to the LDM algorithm,which can optimize the margin distribution and achieve better generalization performance.The WLLDM algorithm is compared with other models by conducting experiments on different datasets.The.experimental results show that the proposed WLLDM has better generalization performance and faster training speed.

关键词： Training Support vector machines Pattern classification Transforms Fasteners Mathematical models Vectors

Fusion of Ground-Based and Spaceborne Radar Precipitation Based on Spatial Domain Regularization

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Journal of Meteorological Research 2024年第2期38卷 285-302页

作者： Anfan HUANG Leilei KOU Yanzhi LIANG Ying mao Haiyang GAO Zhigang chu School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044

High-quality and accurate precipitation estimations can be obtained by integrating precipitation information measures using ground-based and spaceborne radars in the same target area.Estimating the true precipitation state is a typical inverse problem for a given set of noisy radar precipitation observations.The regularization method can appropriately constrain the inverse problem to obtain a unique and stable solution.For different types of precipitation with different prior distributions,the L_(1) and L_(2) norms were more effective in constraining stratiform and convective precipitation,respectively.As a combination of L_(1) and L_(2) norms,the Huber norm is more suitable for mixed precipitation types.This study uses different regularization norms to combine precipitation data from the C-band dual-polarization ground radar(CDP)and dual-frequency precipitation radar(DPR)on the Global Precipitation Measurement(GPM)mission core satellite.Compared to single-source radar data,the fused figures contain more information and present a comprehensive precipitation structure encompassing the reflectivity and precipitation fields.In 27 precipitation cases,the fusion results utilizing the Huber norm achieved a structural similarity index measure(SSIM)and a peak signal-to-noise ratio(PSNR)of 0.8378 and 30.9322,respectively,compared with the CDP data.The fusion results showed that the Huber norm effectively amalgamate the features of convective and stratiform precipitation,with a reduction in the mean absolute error(MAE;16.1%and 22.6%,respectively)and root-mean-square error(RMSE;11.7%and 13.6%,respectively)compared to the 1-norm and 2-norm.Moreover,in contrast to the fusion results of scale recursive estimation(SRE),the Huber norm exhibits superior capability in capturing the localized precipitation intensity and reconstructing the detailed features of precipitation.

关键词： dual-frequency precipitation radar(DPR) dual-polarization radar data fusion regularization Huber norm

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Single-atom Co alloyed Ru for electrocatalytic nitrite reduction to ammonia

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Nano Research 2024年第5期17卷 3660-3666页

作者： Fuzhou Wang Jiaqi xiang Guike Zhang Kai Chen Ke chu School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

Electrochemical converting NO_(2)^(-)into NH_(3)(NO_(2)RR)holds an enormous prospect to attain efficient NH_(3) electrosynthesis and polluted NO_(2)^(-)mitigation.Herein,we report single-atom Co alloyed Ru(Co_(1)Ru)as an efficient and durable NO_(2)RR catalyst.Extensive experimental and theoretical investigations reveal that single-atom Co alloying of Ru enables the construction of Co_(1)-Ru heteronuclear active sites to synergistically promote NO_(2)^(-)activation/hydrogenation while suppressing the competitive H_(2) evolution,rendering the greatly enhanced activity and selectivity of Co_(1)Ru towards the NO_(2)RR.Consequently,Co_(1)Ru assembled within a flow cell exhibits an impressive NH_(3) yield rate of 2379.2μmol·h^(-1)·cm^(-2) with an NH_(3)-Faradaic efficiency of 92%at a high current density of 415.9 mA·cm^(-2),which is among the highest NO_(2)RR performances reported to date.

关键词： electrochemical converting NO_(2)-into NH3 single-atom alloys theoretical computations industrial-level current density

Biomineralization and mineralization using microfluidics:A comparison study

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 661-669页

作者： Yang Xiao xiang He Guoliang Ma Chang Zhao Jian chu Hanlong Liu Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400045China School of Civil Engineering Chongqing UniversityChongqing400045China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore

Biomineralization through microbial process has attracted great attention in the field of geotechnical engineering due to its ability to bind granular materials,clog pores,and seal fractures.Although minerals formed by biomineralization are generally the same as that by mineralization,their mechanical behaviors show a significant discrepancy.This study aims to figure out the differences between biomineralization and mineralization processes by visualizing and tracking the formation of minerals using microfluidics.Both biomineralization and mineralization processes occurred in the Y-shaped sandcontaining microchip that mimics the underground sand layers.Images from different areas in the reaction microchannel of microchips were captured to directly compare the distribution of minerals.Crystal size and numbers from different reaction times were measured to quantify the differences between biomineralization and mineralization processes in terms of crystal kinetics.Results showed that the crystals were precipitated in a faster and more uncontrollable manner in the mineralization process than that in the biomineralization process,given that those two processes presented similar precipitation stages.In addition,a more heterogeneous distribution of crystals was observed during the biomineralization process.The precipitation behaviors were further explained by the classical nucleation crystal growth theory.The present microfluidic tests could advance the understanding of biomineralization and provide new insight into the optimization of biocementation technology.

关键词： Microbially induced carbonate precipitation (MICP) Biocementation Crystal Calcium carbonate Nucleation

A data-driven approach to RUL prediction of tools

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Advances in Manufacturing 2024年第1期12卷 6-18页

作者： Wei Li Liang-Chi Zhang chu-Han Wu Yan Wang Zhen-xiang Cui Chao Niu Department of Mechanical Engineering University College LondonLondonWC1E 7JEUK Shenzhen Key Laboratory of Cross-Scale Manufacturing Mechanics Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China SUSTech Institute for Manufacturing Innovation Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China School of Mechanical and Manufacturing Engineering The University of New South WalesKensingtonNSW2052Australia Baoshan Iron&Steel Co. Ltd.Shanghai200941People’s Republic of China

An effective and reliable prediction of the remaining useful life(RUL)of a tool is important to a metal forming process because it can significantly reduce unexpected maintenance,avoid machine shutdowns and increase system stability.This study proposes a new data-driven approach to the RUL prediction for metal forming processes under multiple contact sliding conditions.The data-driven approach took advantage of bidirectional long short-term memory(BLSTM)and convolutional neural networks(CNN).A pre-trained lightweight CNN-based network,WearNet,was re-trained to classify the wear states of workpiece surfaces with a high accuracy,then the classification results were passed into a BLSTM-based regression model as inputs for RUL estimation.The experimental results demonstrated that this approach was able to predict the RUL values with a small error(below 5%)and a low root mean square error(RMSE)(around 1.5),which was more superior and robust than the other state-of-the-art methods.

关键词： Remaining useful life(RUL) Bidirectional long short-term memory(BLSTM) Data-driven approach Metal forming

Heterophase junction engineering-induced Co spin-state modulation of CoSe2 for large-current hydrogen evolution reaction

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Rare Metals 2024年第6期43卷 2660-2670页

作者： Bao-Chai Xu Ya-Ping Miao Min-Qin mao Dong-Lian Li Song Xie Wei-Hong Jin Shu Xiao Jing Wen Zaenab Abd-Allah Zhi-Tian Liu xiang Peng Paul K.chu Hubei Key Laboratory of Plasma Chemistry and Advanced Materials School of Materials Science and EngineeringWuhan Institute of Technology School of Textile Science and Engineering Xi'an Polytechnic University Institute of Advanced Wear and Corrosion Resistant and Functional Materials Jinan University Institute of Safety Science and Engineering South China University of Technology Department of Engineering Manchester Metropolitan University Department of Physics Department of Materials Science and Engineeringand Department of Biomedical EngineeringCity University of Hong Kong

Efficient electrocatalysts are vital to large-current hydrogen production in commercial water splitting for green energy generation.Herein,a novel heterophase engineering strategy is described to produce polymorphic CoSe2electrocatalysts.The composition of the electrocatalysts consisting of both cubic CoSe2（c-CoSe2） and orthorhombic CoSe2（o-CoSe2） phases can be controlled precisely.Our results demonstrate that junction-induced spin-state modulation of Co atoms enhances the adsorption of intermediates and accelerates charge transfer resulting in superior large-current hydrogen evolution reaction（HER）properties.Specifically,the CoSe2-based heterophase catalyst with the optimal c-CoSe2content requires an overpotential of merely 240 mV to achieve 1,000 mA·cm-2as well as a Tafel slope of 50.4 mV·dec-1.Furthermore,the electrocatalyst can maintain a large current density of 1,500 mA·cm-2for over 320 h without decay.The results reveal the advantages and potential of heterophase junction engineering pertaining to design and fabrication of low-cost transition metal catalysts for large-current water splitting.

关键词： Heterophase junction Spin-state Hydrogen evolution reaction Large current electrochemical hydrogen production Water splitting

S1-supported Pd@CeO_(2) quasi-core@shell materials as advanced catalysts for selective hydrogenation of furfural

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Chinese Chemical Letters 2024年第3期35卷 493-496页

作者： xiang chu Lingling Zhang Ke Wang Rui Zhang Xiao Wang Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Bare Pd metal nanoparticles invariably suffer from poor selectivity in furfural hydrogenation by forming flat configurations,with the aromatic ring of the substrate molecules parallel to the metal surface.Herein,we put forward a promising solution by using CeO_(2)as promoters to modify Pd nanoparticles for modulating the adsorption behaviors of furfural molecules.To achieve the highly-desired ultra-small Pd@CeO_(2)core@shell nanostructure,a“constrained auto-redox”synthesis is developed,in which silicalite-1 supports play the key role of providing their surface as the landing place of PdO_(x)precursors for inhibiting the overgrowth and the deformation.To the best of our knowledge,this is one of the smallest core@shell materials obtained from aqueous synthesis.When evaluated as catalysts,Pd@CeO_(2)/S-1 gives 98.9%conversion of furfural with 94.3%selectivity for furfural alcohol in 15 h,which is much better than that of Pd/S-1(88.6%conversion with 44.3%selectively).The DFT simulation reveals a strong interaction between the defects of CeO_(2)and the oxygen atom of the–CHO group in furfural molecules,which benefits the selective hydrogenation occurred in the–CHO group rather than the furan ring.

关键词： Core@shell Palladium Ceria Auto-redox synthesis Hydrogenation

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A High-Contrast Autolysosome Probe for Detecting Interaction between Autophagosomes and Autolysosomes in Mitophagy

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Chinese Journal of Chemistry 2024年第8期42卷 858-866页

作者： Weihua Wang chu Han Shengjie Xie Zisong Cong Zixuan Yang Yuxin Feng Limin xiang Heng Song College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,Autophagy is a multi-step cell metabolism process in which cells remove damaged and unwanted materials.During autophagy,autophagosomes fuse with lysosomes to form autophagosomes.Autophagosomal membrane components are recycled from autolysosomes through the autophagosomal components recycling(ACR),while lysosomal components circulate on the autolysosomal surface through the autophagic lysosome reformation(ALR)process.Autolysosomes contain components from autophagosomes and lysosomes.However,whether there is a fusion between autolysosome and autophagosome or lysosome at the organelle level remains unknown.In this study,a pH and viscosity dual-controlled mitochondria-targeting fluorescent probe Mito-Q was designed based on an asymmetric norcyanine to achieve the high-contrast imaging of mitochondria-containing autolysosomes.Mito-Q not only effectively detected mitochondrial viscosity changes and mitophagy with high sensitivity,but more importantly,the fusion of mitochondria-containing autolysosomes and autophagosomes(FMAA)was observed during autophagy by the real-time confocal imaging of HeLa cells.

关键词： Mitophagy Autolysosomes Bioimaging Biosensors Fluorescence imaging

Bi^(3+)-activated dual-wavelength emitting phosphors toward effective optical thermometry

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Chinese Chemical Letters 2024年第3期35卷 486-492页

作者： Yu Xue Yuqi Chen Guixian Li Weixi Xia Qinan mao Lang Pei Meijiao Liu Liang chu Jiasong Zhong Center of Advanced Optoelectronic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310018China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China

Optical thermometry as an important local temperature-sensing technique,has received increasing attention in scientific and industrial areas.However,it is still a big challenge to develop luminescent materials with self-activated dual-wavelength emissions toward high-sensitivity optical thermometers.Herein,a novel ratiometric thermometric strategy of Bi^(3+)-activated dual-wavelength emission band was realized in the same lattice position with two local electronic states of La_(3)Sb_(1-x)Ta_xO_(7):Bi^(3+)(0≤x≤1.0)materials based on the different temperature-dependent emission behaviors,benefiting from the highlysensitive and regulable emission to the coordination environment of Bi^(3+).The structural and spectral results demonstrate that the emission tremendously shifted from green to blue with 68 nm and the intensity was enhanced 2.6 times.Especially,the visual dual-wavelength emitting from two emission centers was presented by increasing the Ta^(5+)substitution concentration to 20%or 25%,mainly originating from the two local electronic states around the Bi^(3+)emission center.Significantly,the dual-wavelength with different thermal-quenching performance provided high-temperature sensitivity and good discrimination signals for optical thermometry in the range between 303 and 493 K.The maximum relative sensitivity reached 2.64%/K(La_(3)Sb_(0.8)Ta_(0.2)O_(7):0.04Bi^(3+)@383 K)and 1.91%/K(La_(3)Sb_(0.75)Ta_(0.25)O_(7):0.04Bi^(3+)@388 K).This work reveals a rational design strategy of different local electronic states around the singledoping multiple emission centers towards practical applications,such as luminescence thermometry and white LED lighting.

关键词： Dual-wavelength emitting Cationic substitution Two local electronic states Optical thermometry Bi^(3+)-doped phosphor

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