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Machine Learning-based Identification of Contaminated Images in light Curve Data Preprocessing

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Research in Astronomy and Astrophysics 2024年第4期24卷 287-295页

作者： Hui li Rong-Wang li peng Shu Yu-Qiang li yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Space Object and Debris Observation Chinese Academy of SciencesNanjing 210023China

Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris *** light curves to determine attitude is the most commonly used *** photometric observations,outliers may exist in the obtained light curves due to various ***,preprocessing is required to remove these outliers to obtain high quality light *** statistical analysis,the reasons leading to outliers can be categorized into two main types:first,the brightness of the object significantly increases due to the passage of a star nearby,referred to as“stellar contamination,”and second,the brightness markedly decreases due to cloudy cover,referred to as“cloudy contamination.”The traditional approach of manually inspecting images for contamination is time-consuming and ***,we propose the utilization of machine learning methods as a *** Neural Networks and SVMs are employed to identify cases of stellar contamination and cloudy contamination,achieving F1 scores of 1.00 and 0.98 on a test set,*** also explore other machine learning methods such as ResNet-18 and light Gradient Boosting Machine,then conduct comparative analyses of the results.

关键词： techniques:image processing methods:data analysis light pollution

Probabilistic seismic inversion based on physics-guided deep mixture density network

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Petroleum Science 2024年第3期21卷 1611-1631页

作者： Qian-Hao Sun Zhao-yun Zong Xin li National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Laoshan Laboratory Qingdao266580ShandongChina CNOOC Research Institute Ltd. Beijing100028China

Deterministic inversion based on deep learning has been widely utilized in model parameters *** by logging data,seismic data,wavelet and modeling operator,deterministic inversion based on deep learning can establish nonlinear relationships between seismic data and model ***,seismic data lacks low-frequency and contains noise,which increases the non-uniqueness of the *** conventional inversion method based on deep learning can only establish the deterministic relationship between seismic data and parameters,and cannot quantify the uncertainty of *** order to quickly quantify the uncertainty,a physics-guided deep mixture density network(PG-DMDN)is established by combining the mixture density network(MDN)with the deep neural network(DNN).Compared with Bayesian neural network(BNN)and network dropout,PG-DMDN has lower computing cost and shorter training time.A low-frequency model is introduced in the training process of the network to help the network learn the nonlinear relationship between narrowband seismic data and low-frequency *** addition,the block constraints are added to the PG-DMDN framework to improve the horizontal continuity of the inversion *** illustrate the benefits of proposed method,the PG-DMDN is compared with existing semi-supervised inversion *** synthetic data examples of Marmousi II model are utilized to quantify the influence of forward modeling part,low-frequency model,noise and the pseudo-wells number on inversion results,and prove the feasibility and stability of the proposed *** addition,the robustness and generality of the proposed method are verified by the field seismic data.

关键词： Deep learning Probabilistic inversion Physics-guided Deep mixture density network

Enhanced cycling stability and rate performance of Co-doped and La_(2)O_(3)-coated liNi_(0.9)Mn_(0.1)O_(2) toward power battery

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Rare Metals 2024年第2期43卷 658-670页

作者： Jia-Qi peng Yuan-Yuan Wei Dong-Ming liu yun li Bin Hu Bin Huang Jian-Wen Yang Shun-Hua Xiao Ren-Heng Wang Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Functional Materials College of Chemistry and BioengineeringGuilin University of TechnologyGuilin541004China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(liBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in *** this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above *** doping can effectively widen layer spacing and reduce li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side ***,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) *** capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.

关键词： High nickel cathode material Co doping La_(2)O_(3) coating Electrochemical performance Electrochemical mechanism

Preparation of three-dimensional nanoporous copper foil with high specific surface area

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Rare Metals 2024年第7期43卷 3430-3437页

作者： Ning Song li-Juan Wang Jun-Feng Wang Juan liao Jian Huang peng-Kang Du yun-Zhi Tang Yu-Hui Tan Xiao-Wei Fan Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry School of Chemistry and Chemical EngineeringJiangxi University of Science and TechnologyGanzhou 341000China

The porous copper foil material has the advantages of ultralight and ultra-thin,and can prevent dangers such as thermal runaway and battery fire,which could be regarded as a prospective material for lithium battery **... 详细信息

关键词： copper porous dimensional

Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy

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China Foundry 2024年第3期21卷 213-220页

作者： Ji-peng li De-gao Qiao Jian li Xiao-yang Luo peng peng Xian-tao Yan Xu-dong Zhang Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735111GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China

The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich *** addition,the primary Al dendrites show significant refinement with an increase in the withdrawal *** relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 *** is a combined effect of grain refinement and second-phase strengthening.

关键词： Galvalume alloy directional solidification microstructure length scale microhardness

A state-of-the-art review on delayed expansion of cemented paste backfill materials

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Rare Metals 2024年第8期43卷 3475-3500页

作者： Meng-Yuan li li-Jie Guo Yue Zhao Lei Zhang Kai Yang Xiao-peng peng Andrew Pan BGRIMM Technology Group Beijing 100160China National Centre for International Research On Green Metal Mining Beijing102628China Department of Civil and Mineral Engineering University of TorontoTorontoON M5S 1A4Canada

Utilizing delayed expansion cemented paste backfill materials(DECPB) in mine backfill operations offers an effective solution to the challenge of achieving proper contact between the in-situ cemented backfill mass and the roof in mined-out areas(backfill-roof contact).This article presents recent progress in both theoretical and experimental research concerning *** types and mechanisms of expansive additives,including expansive agents,foaming agents,and expansive mineral materials relevant to DECPB,are explained,along with their impact on the expansive properties and mechanical characteristics of *** composition,material characteristics,preparation methods,and controlled release mechanisms of microcapsules are *** methods for measuring the volume change rate of paste backfill slurries are *** indicates that an appropriate content of expansive additives not only enhances the expansive properties of cemented paste backfill materials but also contributes to improving their mechanical *** foaming agents and bentonite are found to be more suitable for preparing DECPB compared to expansive *** delayed expansion of cemented paste backfill material is influenced by microcapsules,with their wall materials,preparation parameters,and the alkaline slurry environment affecting their controlled release *** and optimizing precise measurement devices and methods forfor the volume change rate of cemented paste backfill materials is essential requirement for studying the performance of *** delayed expansion technology with retarding techniques in cemented paste backfill materials can provide a reliable solution for achieving proper backfill-roof contact in the future.

关键词： Paste backfill Delayed expansion Mining with backfill Expansive additives Tailings

Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau

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Journal of Forestry Research 2024年第1期35卷 72-82页

作者： Teng li Jianfeng peng Tsun Fung Au Jingru li Jinbao li Yue Zhang School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006People’s Republic of China College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Institute for Global Change Biology School for Environment and SustainabilityUniversity of MichiganAnn ArborMIUSA Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMIUSA Department of Geography University of Hong KongHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan ***-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although *** was more sensitive than *** strong-est correlation was between *** chronology and regional mean temperatures from June to *** on this relationship,a regional mean temperature from June to November for the period 1605-2016 was *** explained 37.3%of the temperature variance during th period *** major warm periods and five major cold periods were *** analysis detected significant interannual and multi-decadal *** also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau.

关键词： Tree-ring analysis Mixed forests Dendroclimatology Qionglai Mountains

Defective Nickel-Iron Layered Double Hydroxide for Enhanced Photocatalytic NO Oxidation with Significant Alleviation of NO2 Production

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Engineering 2024年第5期36卷 276-284页

作者： Xiaoyu li Xiaoshu Lv Jian Pan peng Chen Huihui peng Yan Jiang Haifeng Gong Guangming Jiang li’an Hou Engineering Research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Technology and Business UniversityChongqing 400067China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Environmental Technology Innovation Center of Jiande Hangzhou Bertzer Catalyst Co.Ltd.Hangzhou 310058China Chongqing Key Laboratory of Green Synthesis and Application College of ChemistryChongqing Normal UniversityChongqing 401331China

Photocatalysis offers a sustainable means for the oxidative removal of low concentrations of NOx(NO,NO2,N2O,N2O5,etc.)from the *** double hydroxides(LDHs)are promising candidate photocatalysts owing to their unique layered and tunable chemical structures and abundant surface hydroxide(OH)moieties,which are hydroxyl radical(OH)***,the practical applications of LDHs are limited by their poor charge-separation ability and insufficient active ***,we developed a facile N_(2)H_(4)-driven etching approach to introduce dual Ni^(2+)and OHvacancies(Niv and OHv,respectively)into NiFe-LDH nanosheets(hereafter referred to as NiFe-LDH-et)to facilitate improved charge-carrier separation and active Lewis acidic site(Fe^(3+)and Ni^(2+)exposed at OHv)*** contrast to inert pristine LDH,NiFe-LDH-et actively removed NO under visible-light ***,Ni_(76)Fe_(24)-LDH-et etched with 1.50 mmol·L^(-1)N_(2)H_(4)solution removed 32.8%of the NO in continuously flowing air(NO feed concentration:500 parts per billion(ppb))under visible-light illumination,thereby outperforming most reported *** and theoretical data revealed that the dual vacancies promoted the production of reactive oxygen species(O_(2)·^(-)andOH)and the adsorption of NO on the *** situ spectroscopy demonstrated that NO was preferentially adsorbed at Lewis acidic sites,particularly exposed Fe^(3+)sites,converted into NO+,and subsequently oxidized to NO3without the notable formation of the more toxic intermediate NO2,thereby alleviating risks associated with its production and emission.

关键词： Vacancie Layered double hydroxide NO+ Photocatalysis NO removal

A rare missense PAX6 mutation causes atypical aniridia in a three-generation Chinese family

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 466-472页

作者： Zhi-Bo lin Chun-yun Feng Jin li An-peng Pan Hai-Sen Sun A-Yong Yu Shi-Hao Chen National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Ophthalmology the Quzhou Affiliated Hospital of Wenzhou Medical UniversityQuzhou People’s HospitalQuzhou 324000Zhejiang ProvinceChina

●AIM:To investigate the molecular diagnosis of a threegeneration Chinese family affected with aniridia,and further to identify clinically a PAX6 missense mutation in members with atypical aniridia.●METHODS:Eleven family members with and without atypical aniridia were *** family members underwent comprehensive ophthalmic examinations.A combination of whole exome sequencing(WES)and direct Sanger sequencing were performed to uncover the causative mutation.●RESULTS:Among the 11 family members,8 were clinically diagnosed with congenital aniridia(atypical aniridia phenotype).A rare heterozygous mutation c.622C>T(***208Trp)in exon 8 of PAX6 was identified in all affected family members but not in the unaffected members or in healthy control subjects.●CONCLUSION:A rare missense mutation in the PAX6 gene is found in members of a three-generation Chinese family with congenital atypical *** result contributes to an increase in the phenotypic spectrum caused by PAX6 missense heterozygous variants and provides useful information for the clinical diagnosis of atypical aniridia,which may also contribute to genetic counselling and family planning.

关键词： PAX6 gene atypical aniridia missense mutation mutation