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Reliability analysis of multimodal scene matching based on correlation peaks

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Chinese Journal of Aeronautics 2024年第9期37卷 433-447页

作者： Zhirui YU Bai zhu Zhiqiang HAN Yuanxin Ye Faculty of Geosciences and engineering Southwest Jiaotong UniversityChengdu 611756China

The navigation system plays a pivotal role in guiding aircraft along designated routes,ensuring precise and punctual arrival at *** integration of scene matching with an inertial navigation system enhances the capability of providing a dependable guarantee for success-ful accomplishment of flight ***,assuring reliability in scene matching encoun-ters significant challenges in areas characterized by repetitive or weak *** tackle these challenges,we propose a novel method to assess the reliability of scene matching based on the dis-tinctive characteristics of correlation *** proposed method leverages the fact that the sim-ilarity of the optimal matching result is significantly higher than that of the surrounding area,and three novel indicators(e.g.,relative height,slope of a correlation peak,and ratio of a sub peak to the main peak)are determined to conjointly evaluate the reliability of scene *** pro-posed method entails matching a real-time image with a reference image to generate a correlation surface.A correlation peak is then obtained by extracting the portion of the correlation surface exhibiting a significant ***,the matching reliability is determined by considering the relative height,slope,and ratio of the peak *** experimental results with two sets of data demonstrate that the proposed method significantly outperforms traditional approaches in terms of precision,recall,and *** experiments also establish the efficacy of the proposed method in achieving reliable matching in challenging environments characterized by repetitive and weak *** enhancement holds the potential to significantly elevate scene-matching-based navigation.

关键词： Unmanned aerial vehicle Scene matching navigation Multimodal scene matching Correlation peak Reliabilityanalysis

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic energy estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng Yuan Yuzhong Zhang Shiqiang Liu Rong zhu State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.18%to 14.71%)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

Photodegradation of xylene isomers:Kinetics,mechanism,secondary pollutant formation potential and health risk evaluation

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Journal of environmental Sciences 2024年第2期136卷 658-669页

作者： Xiaoyan Chen Weikun zhu Sufen Feng Jiangyao Chen Guangdong Key Laboratory of environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Photodegradation technology has been widely applied in the purification of industrial aromatic ***,whether this technology efficiently removes the pollutants to prevent secondary pollution and health risk is still ***,the photodegradation processes of three xylenes were compared under designed reaction atmospheres and light *** lamp showed poor photodegradation ability toward xylenes,no matter in N_(2) or N_(2)+O_(2)system,while much higher photodegradation performance of xylenes were obtained under ultraviolet(UV)and vacuum ultraviolet(VUV)irradiation,especially in N_(2)+O_(2)+VUV system,where 97.9%of m-xylene,99.0%of o-xylene or 87.5%of p-xylene with the initial concentration of 860 mg/m^(3) was removed within 240 *** xylenes underwent three processes of photo-isomerization,photodecomposition and photo-oxidation to produce intermediates of aromatics,alkanes and *** them,the photo-isomerization products showed the highest concentration percentage(e.g.,≥50%in o-xylene system),confirming that photo-isomerization reaction was the dominated photodegradation process of ***,these isomerized products not only contributed about 97%and91%to the formation potential of O3(OFP)and secondary organic aerosols(SOAFP),but also displayed obvious non-carcinogenic risk,although one of photodecomposition product—benzene showed the highest occupational exposure ***,the secondary pollution and health risks of photodegradation products of xylenes were non-ignorable,although the OFP,SOAFP and health risks of the generated products reduced at least 4.5 times in comparison with that of the degraded *** findings are helpful for the appropriate application of this technology in the purification of industrial organic waste gas.

关键词： Isomer aromatics Photodegradation Ozone formation Secondary organic aerosols Health risk

DeM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

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Particuology 2024年第2期85卷 198-212页

作者： Minyi zhu Guobin Gong Jun Xia Stephen Wilkinson Department of Civil engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DeM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

Concentration-dependent effects of reductive pulmonary inhalants on ultrafine particle-induced oxidative stress:Insights for health risk assessment

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environmental Science and ecotechnology 2024年第3期19卷 118-124页

作者： Ya-qi Yu Tong zhu BIC-eSAT and SKL-eSPC College of Environmental Sciences and EngineeringPeking UniversityBeijing100871PR China School of environmental Science and engineering Qingdao UniversityQingdao266071PR China

The impact of reductive pulmonary inhalants on ultrafine particles(UFPs)-induced pulmonary oxidative stress remains a crucial consideration,yet the concentration-dependent effects of these inhalants have remained *** we synthesized composite UFPs simulating atmospheric UFPs,primarily composed of metals and *** subjected these UFPs to varying concentrations(0e7000 mM)of two reductive pulmonary inhalants,N-acetylcysteine and salbutamol,to assess their influence on oxidative potential,measured through the dithiothreitol assay(OP^(DTT)).Simultaneously,we analysed the soluble metal content of UFPs to uncover potential relationships between oxidative potential and metal *** results unveil a dual role played by these inhalants in shaping the OPDTT of composite ***,OP^(DTT) generally increased as inhalant concentrations rose from 0 to 300 ***,an intriguing reversal occurred when concentrations exceeded 500 mM,resulting in a decline in *** to untreated UFPs,these inhalants induced promotion and inhibition effects within concentration ranges of 100e500 and>1000 mM,*** no significant correlation emerged between OP^(DTT) and soluble metal content as inhalant concentrations ranged from 0 to 7000 mM,noteworthy positive correlations emerged at lower inhalant concentrations(e.g.,N-acetylcysteine at 0 e300 mM).These findings provide insights into the potential influence of reductive pulmonary inhalants on health risks associated with UFP exposure,further underscoring the need for continued research in this critical area.

关键词： Concentration-dependent effects Oxidative potential Reductive pulmonary inhalants Soluble metals Simulated atmospheric ultrafine particles

efficient ammonia production over e_(g)-occupancy-optimized perovskite electrocatalysts

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Nano Research 2024年第6期17卷 4682-4686页

作者： Mingfa Chen Yu Zhang Fulong Liu Zhenbao Zhang Yuming Dong Yongfa zhu Heqing Jiang Jiawei zhu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China School of Chemistry and Chemical engineering Linyi UniversityLinyi 276005China Department of Chemistry Tsinghua UniversityBeijing 100084China

Renewable-energy-driven nitrate(NO_(3)^(−))electroreduction to ammonia(NH_(3))(NeRA)has been an attractive technology for decarbonizing NH_(3)production and wastewater *** NeRA efficiency requires electrocatalysts that are earth-abundant and show fantastic *** we report a semiempirical activity descriptor of eg occupancy(of surface B-site cations)for identifying inexpensive perovskite oxides with extremely high efficacy toward *** establish the descriptor by systematic investigations of more than 10 perovskite *** investigations demonstrate that their intrinsic NeRA activities display a volcano-shaped dependence on eg occupancy and the optimized intrinsic activities are accessible at near-1 eg *** could plausibly be attributed to the favorable overlaps between surface adsorbates and vertically-oriented eg *** importantly,utilizing this descriptor,we predict a highly active,selective,and durable NeRA electrocatalyst with a composition of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3−δ)(BSCF).Because of its close-to-1 e_(g)occupancy(i.e.~1.2),the BSCF features a superior NH_(3)production rate of 0.12 g·h^(−1)·mg_(cat.)^(−1)(Faradaic efficiency of 97.8%)that is at top of the volcano plot,and substantially outperforms most NeRA electrocatalysts reported in literature.

关键词： perovskite oxide nitrate electroreduction ammonia electrosynthesis eg occupancy

A single atom photocatalyst co-doped with potassium and gallium for enhancing photocatalytic hydrogen peroxide synthesis

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Nano Research 2024年第8期17卷 7027-7038页

作者： Wenan Cai Yuichiro Tanaka Xing zhu Teruhisa Ohno Department of Applied Chemistry Faculty of EngineeringKyushu Institute of TechnologyKitakyushu 804-8550Japan College of Bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXi’an 710021China

Polymer carbon nitride(PCN)is widely used in ***,pristine PCN has disadvantages such as insufficient visible light absorption and low photogenerated carrier separation efficiency that greatly limited the photocatalytic *** a non-toxic metal,gallium has the potential to solve the defects of *** ions coordinated with nitrogen in carbon nitride to form Ga-N active sites and improved the photocatalytic *** doped potassium ions form a transmission channel for charge redistribution and transfer between adjacent layers,which is beneficial for better separation of photoexcited *** this study,a series of PCN co-doped with gallium and potassium(Ga-K-PCN)were *** experimental results indicated photocatalytic generation of hydrogen peroxide proceeds through the 2e−oxygen reduction reaction ***,Nyquist plots and photocurrent results further proved that the presence of Ga-N sites and potassium ion doping could significantly improve the separation/transfer of intra-planar and interlayer charge carriers and thus enhance photocatalytic *** Ga10-K3-PCN photocatalysts promoted yield of H_(2)O_(2),with reactivity at 28.2μmol/(g·h)and solar-to-chemical conversion efficiency at 0.64%,surpassed that of a typical photo-catalyst based on PCN(0.18%).

关键词： photocatalysis gallium oxygen reduction reaction H_(2)O_(2) production

Growth process,defects,and dopants of bulkβ-Ga_(2)O_(3)semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： Yan-shen Wang Ming-zhi zhu Yuan Liu School of Materials Science and engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-sizeβ-Ga_(2)O_(3)single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3)are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3)single crystals are summarized and compared in ***,the defects ofβ-Ga_(2)O_(3)single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3)are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3)single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

Bifunctional two-carbon reagent made from acetylene via 1,2-difunctionalization and its applications

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Science China Chemistry 2024年第3期67卷 936-944页

作者： Bo Yang Kangkui Li Yongdong Wang Shifa zhu Key Laboratory of Functional Molecular engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Singfar Laboratories Guangzhou 510670China

There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(e)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.

关键词： acetylene 1 2-difunctionalization photocatalysis vinylsulfone