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Biderivations of Hom-Lie Algebras and Superalgebras

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2337-2358页

作者： la Mei YUAN Jia Xin LI School of Mathematics Harbin Institute of Technology

On Hom-Lie algebras and superalgebras, we introduce the notions of biderivations and linear commuting maps, and compute them for some typical Hom-Lie algebras and superalgebras,including the q-deformed W(2, 2) algebra... 详细信息

关键词： 17A30 17A60 17B05 17B60 17B70 biderivations Hom-Lie algebras linear commuting maps q-deformed W(2 2) algebra q-deformed Witt algebra q-deformed Witt superalgebra

Truly optimal semi-active damping to control free vibration of a single degree of freedom system

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 142-145页

作者： Viet Duc la Ngoc Tuan Nguyen Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and *** pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping.

关键词： Analytical optimization Quadratic integral Lyapunov equation Pontryagin maximum principle

A convolutional neural network to detect possible hidden data in spatial domain images

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Cybersecurity 2024年第1期7卷 37-52页

作者： Jean De la Croix Ntivuguruzwa Tohari Ahmad Department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African Center of Excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the ***,attackers with a steganalysis technique may break *** steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of Convolutional Neural Network(CNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based *** the existing CNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training *** research proposes a new method with a CNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain *** proposed method comprises three phases:pre-processing,feature extraction,and ***,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax *** results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis Deep learning Convolutional neural network Infrastructure

ZnSb/Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction for flexible near-infrared photodetector arrays

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Journal of Semiconductors 2024年第5期45卷 99-105页

作者： Chuqiao Hu Ruiqing Chai Zhongming Wei la Li Guozhen Shen State Key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China

Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)***,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography *** single ZnSb/Ti_(3)C_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)C_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals *** polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)C_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending ***,the ZnSb/Ti_(3)C_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application.

关键词： ZnSb nanoplates Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction flexible photodetector image sensing

High Seebeck Coefficient Thermally Chargeable Supercapacitor with Synergistic Effect of Multichannel Ionogel Electrolyte and Ti_(3)C_(2)T_(x)MXene-based Composite Electrode

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Energy & Environmental Materials 2024年第6期7卷 367-377页

作者： Zhongming Chen Zhijian Du la Li kai Jiang Di Chen Guozhen Shen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China Faculty of Hepato-Pancreato-Biliary Surgery Chinese PLA General HospitalInstitute of Hepatobiliary Surgery of Chinese PLA&Key Laboratory of Digital Hepetobiliary SurgeryChinese PLABeijing 100853China

Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable ***,the low Seebeck coefficient and heat-to-electricity conversion efficiency hinder further *** this paper,we designed a high-performance thermally chargeable supercapacitor device composed of ZnMn_(2)O_(4)@Ti_(3)C_(2)T_(x)MXene composites(ZMO@Ti_(3)C_(2)T_(x)MXene)electrode and UIO-66 metal–organic framework doped multichannel polyvinylidene fluoridehexafluoro-propylene ionogel electrolyte,which realized the thermoelectric conversion and electrical energy storage at the same *** thermally chargeable supercapacitor device exhibited a high Seebeck coefficient of 55.4 mV K^(−1),thermal voltage of 243 mV,and outstanding heat-to-electricity conversion efficiency of up to 6.48%at the temperature difference of 4.4 *** addition,this device showed excellent charge–discharge cycling stability at high-temperature differences(3 K)and low-temperature differences(1 K),*** two thermally chargeable supercapacitor units in series,the generated output voltage of 500 mV further confirmed the stability of *** a single device was worn on the arm,a thermal voltage of 208.3 mV was obtained indicating the possibility of application in wearable electronics.

关键词： ionogel electrode Soret effect thermally chargeable supercapacitor Ti_(3)C_(2)T_(x)MXene UIO-66 MOF

The Influence of Significant Public Health Events on Offline Consumption and Its Pathways

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 627-648页

作者： baile Lu Kewei Zhou Shuai Hao la Ta Hongyan Dai Weihua Zhou College of Systems Engineering National University of Defense TechnologyChangsha 410073China Business School Central University of Finance and EconomicsBeijing 100081China Department of Marketing and Operations Management College of BusinessSouthern University of Science and TechnologyShenzhen 518055China School of Management Zhejiang UniversityHangzhou 310058China

In the face of a significant public health event,consumers may either increase their panic buying or decrease their willingness to make *** study focuses on the impact of a significant public health event on offline store sales and consumer consumption,utilizing data from chain convenience stores in Hefei and Wuhu during early 2019 and early 2020 in *** a difference-in-differences model,the study investigates the effect of the significant public health event outbreak on weekly store sales,order numbers,and consumer consumption in terms of product quantities,transaction amount,average amount per order,and transaction *** from prior literature that finds hoarding behavior of consumers online,the findings of this paper indicate a significant reduction in stores’offline weekly sales and order numbers,as well as consumers’offline weekly consumption across the four dimensions,as a result of the significant public health event ***,employing a mediation model,the study explores the pathway of population mobility through which the significant public health event adversely affects offline ***,subset analysis is conducted for stores located in different areas and consumers with varying characteristics,revealing that the aforementioned conclusions predominantly apply to stores situated in office areas and residential areas,as well as consumers with either no apparent preference for different product categories or a noticeable preference for food.

关键词： Significant public health event offline consumption population mobility mediating effect

An exploration of meteorological effects on PM2.5 air quality in several provinces and cities in Vietnam

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Journal of Environmental Sciences 2024年第11期145卷 139-151页

作者： Giang Tran Huong Nguyen Luan Thien la Huy Hoang-Cong Anh Hoang Le Faculty of Chemistry and Environment Dalat UniversityLam Dong ProvinceVietnam Environmental Protection Agency Lam Dong Province Department of Natural Resources and EnvironmentLam Dong ProvinceVietnam Northern Center for Environmental Monitoring Environmental Pollution Control DepartmentHa Noi CityVietnam Faculty of Environment University of ScienceHo Chi Minh CityVietnam Vietnam National University Ho Chi Minh CityVietnam

Linking meteorology and air pollutants is a key *** study investigated meteorological effects on PM_(2.5)concentration using the advanced convergent cross mapping method,utilizing hourly PM_(2.5)concentration and six meteorological factors across eight provinces and cities in *** demonstrated that temperature(ρ=0.30)and radiation(ρ=0.30)produced the highest effects,followed by humidity(ρ=0.28)and wind speed(ρ=0.24),while pressure(ρ=0.22)and wind direction(ρ=0.17)produced the weakest effects on PM_(2.5)*** theρvalues showed that temperature,wind speed,and wind direction had greater impacts on PM_(2.5)concentration during the dry season whereas radiation had a more influence during the wet season;Southern stations experienced larger meteorological ***,humidity,pressure,and wind direction had both positive and negative influences on PM_(2.5)concentration,while radiation and wind speed mostly had negative *** PM_(2.5)pollution episodes,there wasmore contribution ofmeteorological effects on PM_(2.5)concentration indicated byρ*** contaminated levels,humidity(ρ=0.45)was the most dominant factor affecting PM_(2.5)concentration,followed by temperature(ρ=0.41)and radiation(ρ=0.40).Pollution episodes were pointed out to be more prevalent under higher humidity,higher pressure,lower temperature,lower radiation,and lower wind ***ρcalculation also revealed that lower temperature,lower radiation,and higher humidity greatly accelerated each other under pollution episodes,further enhancing PM_(2.5)*** findings contributed to the literature on meteorology and air pollution interaction.

关键词： Fine particulate matter Air pollution Meteorological effect Convergent cross mapping Causality analysis Vietnam

Woody plant taxonomic,functional,and phylogenetic diversity decrease along elevational gradients in Andean tropical montane forests:Environmental filtering and arrival of temperate taxa

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Plant Diversity 2024年第4期46卷 491-501页

作者： Guillermo bañares-de-Dios Manuel J.Macía gabriel Arellano Íñigo Granzow-de la Cerda Julia Vega-álvarez Itziar Arnelas Carlos I.Espinosa Norma Salinas Luis Cayuela Departamento de Biología y Geología Física y Química InorgánicaUniversidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain Departamento de Biología Área de BotánicaUniversidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Centro de Investigación en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA Oikobit LLC ***AlbuquerqueNM87120USA Real Jardín Botánico–CSIC Plaza Murillo 2MadridES-28014Spain Departamento de Biología Animal EcologíaParasitologíaEdafología y Química AgrícolaUniversidad de SalamancaCalle Donantes de Sangre s/nSalamancaES-37007Spain Departamento de Biodiversidad Ecología y EvoluciónUniversidad Complutense de MadridCalle JoséAntonio Nováis 12Ciudad UniversitariaES-28040Spain Departamento de Ciencias Biológicas y Agropecuarias Universidad Técnica Particular de LojaA.P.11-01-608 LojaEcuador Sección Química Pontificia Universidad Católica del PerúA.P.Lima 32LimaPeru ECI School of Geography and EnvironmentUniversity of OxfordOX13QYOxfordshireUnited Kingdom Instituto de Investigación en Cambio Global(IICG-URJC) Universidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain

Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short *** research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients,but other facets should be *** first time,we simultaneously assessed elevational trends in taxonomic,functional,and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary *** investigation covered four transects(traversing ca.2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range(ca.10°).Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic,functional,and phylogenetic diversity as elevation increased,although the decrease was less pronounced for higher Hill *** exception was a slight increase in phylogenetic diversity when dominant species were *** decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands,where the increasingly harsher conditions exclude species and functional ***,the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional *** phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate *** could be explained by a decreasing presence and abundance of temperate,extratropical taxa towards the central Andes relative to northern or southern Andes,where they are more prevalent.

关键词： Altitudinal gradients Andes Environmentalﬁltering Out of the Tropical Lowlands Functional rarity Tropical Niche Conservatism

Polarization Study of Swift J151857.0–572147 with IXPE Observation

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Research in Astronomy and Astrophysics 2024年第9期24卷 60-65页

作者： Yu-Shan Ling Fei Xie Ming-Yu Ge Fabio la Monaca Guangxi Key laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China INAF Istituto di Astrofisica e Planetologia Spaziali Via del Fosso del Cavaliere 10000133 RomaItaly Dipartimento di Fisica Universitàdegli Studi di Roma“Tor Vergata”Via della Ricerca Scientifica 100133 RomaItaly Dipartimento di Fisica Universitàdegli Studi di Roma“La Sapienza”Piazzale Aldo Moro 500185 RomaItaly

We present an analysis of the Imaging X-ray Polarimetry Explorer observation from a newly discovered transient source:Swift *** obtained polarization degree(PD)and angle are 0.3%±0.3% and -24°±26°respectively in 2-8 keV within 68%confidence level errors,and polarization results are below MDP99in all energy bins,with the upper limit on PD of 0.8% in the 2-8 keV energy *** quasi-periodic oscillations(QPOs)are detected in this *** polarization and QPO analyses support the hypothesis that the source was in the high soft state,and the results are consistent with predictions for a thin accretion disk model.

关键词： stars:black holes polarization X-rays:bursts