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Rethinking attribute localization for zero-shot learning

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Science China(Information Sciences) 2024年第7期67卷 184-196页

作者： Shuhuang chen Shiming chen guo-Sen XIE Xiangbo SHU Xinge YOU Xuelong LI School of Electronic Information and Communication Huazhong University of Science and Technology School of Computer Science and engineering Nanjing University of Science and Technology School of Artificial Intelligence Optics and Electronics Northwestern Polytechnical University

Recent advancements in attribute localization have showcased its potential in discovering the intrinsic semantic knowledge for visual feature representations, thereby facilitating significant visual-semantic interactions essential for zero-shot learning(ZSL). However, the majority of existing attribute localization methods heavily rely on classification constraints, resulting in accurate localization of only a few attributes while neglecting the rest important attributes associated with other classes. This limitation hinders the discovery of the intrinsic semantic relationships between attributes and visual features across all *** address this problem, we propose a novel attribute localization refinement(ALR) module designed to enhance the model's ability to accurately localize all attributes. Essentially, we enhance weak discriminant attributes by grouping them and introduce weighted attribute regression to standardize the mapping values of semantic attributes. This module can be flexibly combined with existing attribute localization *** experiments show that when combined with the ALR module, the localization errors in existing methods are corrected, and state-of-the-art classification performance is achieved.

关键词： zero-shot learning attention mechanism attribute localization image classification

Comparative Analysis of Diagonal and Centrifugal Compressors with Synergy Theory in Compressed Air energy Storage System

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Journal of Thermal Science 2024年第4期33卷 1325-1339页

作者： ZHANG Yuxin ZUO Zhitao ZHOU Xin guo Wenbin chen Haisheng Institute of engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China National energy Large Scale Physical energy Storage Technologies R&D Center of Bijie Bijie551700China Nanjing Institute of Future energy System IETCASNanjing211135China

energy storage technology is an essential part of the efficient energy *** air energy storage(CAES)is considered to be one of the most promising large-scale physical energy storage *** is favored because of its low-cost,long-life,environmentally friendly and low-carbon *** compressor is the core component of CAES,and the performance is critical to the overall system *** importance is not only reflected in the design point,but also in the continuous efficient operation under variable working *** diagonal compressor is currently the focus of the developing large-scale CAES because of its stronger flow capacity compared with traditional centrifugal *** the diagonal compressor has the higher single stage pressure ratio compared with axial *** this paper,the full three dimensional numerical simulation technologies with synergy theory are used to compare and analyze the internal flow *** performance of the centrifugal and diagonal impellers that are optimized under the same requirements for large-scale CAES has been *** relationship between the internal flow characteristics and performance of the centrifugal and diagonal impellers with the change of mass flow rates and total inlet temperature is given qualitatively and *** the cosine value of the synergy angle is high,the local flow loss is *** smaller proportion of the positive area is the pursuit of *** comparative analysis,it is concluded that the internal flow and performance changes of centrifugal and diagonal impellers are *** results confirm the superiority and feasibility of the off-design performance of the diagonal compressor applied to the developing large-scale CAES.

关键词： compressed air energy storage synergy theory diagonal compressor centrifugal compressor comparative analysis

Stabilizing iridium sites via interface and reconstruction regulations for water oxidation in alkaline and acidic media

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Journal of energy Chemistry 2024年第2期89卷 355-363,I0009页

作者： Weibin chen Yanhui Song Lei Li Junjie guo Zhan Lin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006GuangdongChina Key Laboratory of Interface Science and engineering in AdvancedMaterials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

Exploring effective iridium(Ir)-based electrocatalysts with stable iridium centers is highly desirable for oxygen evolution reaction(OER).Herein,we regulated the incorporation manner of Ir in Co_(3)O_(4)support to stabilize the Ir sites for effective *** anchored on the surface of Co_(3)O_(4)in the form of Ir(OH)_6 species,the created Ir-OH-Co interface leads to a limited stability and poor acidic OER due to Ir *** doped into Co_(3)O_(4)lattice,the analyses of X-ray absorption spectroscopy,in-situ Raman,and OER measurements show that the partially replacement of Co in Co_(3)O_(4)by Ir atoms inclines to cause strong electronic effect and activate lattice oxygen in the presence of Ir-O-Co interface,and simultaneously master the reconstruction effect to mitigate Ir dissolution,realizing the improved OER activity and stability in alkaline and acidic *** a result,Ir_(lat)@Co_(3)O_(4)with Ir loading of 3.67 wt%requires 294±4 mV/285±3 mV and 326±2 mV to deliver 10 mA cm^(-2)in alkaline(0.1 M KOH/1.0 M KOH)and acidic(0.5 M H_(2)SO_(4))solution,respectively,with good stability.

关键词： Interface effect Reconstruction Ir dissolution Ir-O-Co Oxygen evolution reaction

Nonlinear dynamics of a circular curved cantilevered pipe conveying pulsating fluid based on the geometrically exact model

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Applied Mathematics and Mechanics(english Edition) 2024年第2期45卷 261-276页

作者： Runqing CAO Zilong guo Wei chen Huliang DAI Lin WANG Department of engineering Mechanics School of Aerospace EngineeringHuazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for engineering Structural Analysis and Safety Assessment Wuhan 430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Due to the novel applications of flexible pipes conveying fluid in the field of soft robotics and biomedicine,the investigations on the mechanical responses of the pipes have attracted considerable *** fluid-structure interaction(FSI)between the pipe with a curved shape and the time-varying internal fluid flow brings a great challenge to the revelation of the dynamical behaviors of flexible pipes,especially when the pipe is highly flexible and usually undergoes large *** this work,the geometrically exact model(GEM)for a curved cantilevered pipe conveying pulsating fluid is developed based on the extended Hamilton's *** stability of the curved pipe with three different subtended angles is examined with the consideration of steady fluid *** attention is concentrated on the large-deformation resonance of circular pipes conveying pulsating fluid,which is often encountered in practical *** constructing bifurcation diagrams,oscillating shapes,phase portraits,time traces,and Poincarémaps,the dynamic responses of the curved pipe under various system parameters are *** mean flow velocity of the pulsating fluid is chosen to be either subcritical or *** numerical results show that the curved pipe conveying pulsating fluid can exhibit rich dynamical behaviors,including periodic and quasi-periodic *** is also found that the preferred instability type of a cantilevered curved pipe conveying steady fluid is mainly in the flutter of the second *** a moderate value of the mass ratio,however,a third-mode flutter may occur,which is quite different from that of a straight pipe system.

关键词： curved pipe conveying fluid pulsating fluid geometrically exact model(GEM) nonlinear dynamics parametric vibration flutter

Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence Technology（防务技术） 2024年第4期34卷 282-294页

作者： Wei Wang Yuchen Wang Shiwei chen Yongcang guo Zhongjiao Shi School of Aerospace engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries Group CO. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate second-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a constant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed composite control framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude control Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

A dual-mode optical thermometer based on dual-excitation Bi^(3+),Sm^(3+)co-doped Y_(4)GeO_(8) phosphors

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Journal of Rare Earths 2024年第8期42卷 1437-1446,I0002页

作者： Danyu Zhang Yuxuan Luo Junyu chen Lianjie Li Hai guo Department of Physics Zhejiang Normal UniversityJinhua321004China

Dual-excitation and dual-emission Y_(4)GeO_(8):Bi^(3+),Sm^(3+)phosphors were manufactured by traditional solidphase sintering *** X-ray diffraction,morphology,photoluminescence,energy transfer process and temperature sensing properties of Y_(4)GeO_(8):Bi^(3+),Sm^(3+)samples were comprehensively *** Y4GeO_(8):Bi^(3+),Sm^(3+)phosphors exhibit characteristic emissions of Bi^(3+)(^(3)P_(1)→^(1)S_(0)) and Sm^(3+)(^(4)G_(5/2)→^(6)H)under both 290 and 347 nm *** fluorescence intensity ratio and Commission International de L'Eclairage coordinates modes,Y_(4)GeO_(8):Bi^(3+),Sm^(3+)samples present excellent temperature measurement *** maximum relative sensitivity(S_(r-max)) values of the former are 1.55%/K(460 K,290 nm excitation) and 0.82%/K(506 K,347 nm excitation).The S_(r-max)(x) values of the latter are 0.21 %/K(437 K,290 nm excitation) and 0.15%/K(513 K,347 nm excitation).These results illustrate that Y_(4)GeO_(8):Bi^(3+),Sm^(3+)phospho rs can be used as a candidate material for a dual-mode optical thermometer under dual-excitation.

关键词： Dual-mode optical thermometer Luminescent properties Y_(4)GeO_(8):Bi^(3+) Sm^(3+)phosphors Rare earths

Progress and prospects of Mg-based amorphous alloys in azo dye wastewater treatment

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Journal of Magnesium and Alloys 2024年第3期12卷 873-889页

作者： Yanan chen Fengchun chen Liang Li chen Su Bo Song Hongju Zhang Shengfeng guo Fusheng Pan School of Materials and energy Southwest UniversityChongqing 400715China Analytical and Testing Center Southwest UniversityChongqing 400715China College of Materials Science and engineering Chongqing UniversityChongqing 400044China

Mg-based amorphous alloys exhibit efficient catalytic performance and excellent biocompatibility with a promising application probability,specifically in the field of azo dye wastewater ***,the problems like difficulty in preparation and poor cycling stability need to be *** present,Mg-based amorphous alloys applied in wastewater degradation are available in powder and *** amorphous alloy powder fabricated by ball milling has a high specific surface area,and its reactivity is thousands of times better than that of gas atomized alloy *** the development is limited due to the high energy consumption,difficult and costly process of powder *** single roller melt-spinning method is a new manufacturing process of amorphous alloy *** to amorphous powder,the specific surface area of amorphous ribbon is relatively lower,therefore,it is necessary to carry out surface modification to enhance *** is a way that can form a pore structure on the surface of the amorphous alloys,increasing the specific surface area and providing more reactive sites,which all contribute to the catalytic *** the optimal conditions for Mg-based amorphous alloys in wastewater degradation by adjusting amorphous alloy composition,choosing suitable method to preparation and surface modification,reducing cost,expanding the pH range will advance the steps to put Mg-based amorphous alloys in industrial environments into practice.

关键词： Mg-based amorphous alloys Azo dyes Dealloying Surface modification Wastewater degradation.

Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation

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Chinese Journal of Chemical engineering 2024年第5期69卷 167-176页

作者： Jinnan guo Daoyin Liu Jiliang Ma Cai Liang Xiaoping chen Key Laboratory of energy Thermal Conversion and Control of Ministry of Education Southeast UniversityNanjing 210096China

The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)*** details of the gas-solid flow behaviors of PCFB are *** on the gas-solid flow pattern,the particles tend to move more orderly under elevated *** an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient *** an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence *** back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient.

关键词： Pressurized circulating fluidized bed MP-PIC method Residence time distribution Axial dispersion coefficient

Design Strategy of Diagonal Compressors in Compressed Air energy Storage System

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Journal of Thermal Science 2024年第3期33卷 872-887页

作者： ZHANG Yuxin ZUO Zhitao guo Wenbin LIANG Qi chen Haisheng Institute of engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China National energy Large Scale Physical energy Storage Technologies R&D Center of Bijie Bijie551700China Nanjing Institute of Future energy System IETCASNanjing211135China

As a kind of large-scale physical energy storage,compressed air energy storage(CAES)plays an important role in the construction of more efficient energy system based on renewable energy in the *** with traditional industrial compressors,the compressor of CAES has higher off-design performance *** the perspective of design,it needs to pay attention not only to the performance of the design point,but also to the performance of all the stable working ***,from the previous literature,no diagonal compressor was used in CAES which can meet the requirements,which also reflects the design program can be further ***,this paper studies the design strategy of high efficient diagonal compressor for large-scale CAES,and gives the complete strategy algorithms used for different program *** pressure ratio,isentropic efficiency and stable working range are comprehensively *** the design process,the criteria for the key parameters of the diagonal flow angle of the diagonal compressor are given for the first *** results show that the isentropic efficiency at the design point is 92.7%,the total pressure ratio is1.97,and the stable working range exceeds 20%,which meets the design requirements of the compressor for CAES and exceeds the overall performance of the previous compressors in the entire working range.

关键词： compressed air energy storage design strategy diagonal compressor optimal selection design procedure