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Numerical investigation of supercontinuum generation and optical frequency combs in Si N-based PCF with high nonlinear coefficient

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Optoelectronics Letters 2024年第3期20卷 163-170页

作者： Mohammad Reza Alizadeh Mahmood Seifouri Saeed Olyaee faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran Nano-photonics and Optoelectronics Research Laboratory(NORLab) Shahid Rajaee Teacher Training UniversityTehranIran

In this paper, a photonic crystal fiber(PCF) with a dispersion-engineered and high nonlinear coefficient has been designed for supercontinuum generation(SCG) and frequency comb generation(FCG). The proposed PCF has a Si_(3)N_(4) rod in the core. This rod provides more optical confinement in the core by increasing the refractive index of the core. This high confinement reduces the effective mode area of PCF and thus increases the nonlinear coefficient.

关键词： optical fiber nonlinear

Technology-Assisted Reading Instruction for English Language Learners:A Methodological Review

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ECNU Review of education 2024年第2期7卷 258-282页

作者：左心阅 Denise Ives Department of teacher education and Curriculum Studies College of Education813 N Pleasant StAmherstMA01003USA

Purpose:By methodologically reviewing the literature on Technology-Assisted Reading Instruction(TARI)for English Language Learners(ELLs)in K-12 settings,this study aims to advance the knowledge of TARI research and guide future research ***/Approach/Methods:This study examines 32 peer-reviewed journal articles published between 2000 and *** article was analyzed for research objectives,reading skills,learner demographics and contexts,theoretical frameworks,research designs,and ***:A review of the literature reveals a strong focus on evaluating the efficacy of TARI through summative assessments,but limited attention to learners'literacy practices and interactive engagement in digital ***,there is a marked lack of alternative approaches to assessing the effectiveness of technology in promoting ELLs'reading progression and a continued emphasis on developing traditional literacy over multimodal *** can enhance reading motivation,foster collaborative learning,provide scaffolding,improve reading performance,andexpand semiotic ***/Value:As one of the first comprehensive methodological reviews of TARl,this study elucidates ELL reading education in the era of *** have implications for technology-mediated education,which expanded rapidly during the COVID-19 pandemic.

关键词： educational technology English language learners multiliteracy reading technology-assisted reading instruction

A review of ethnobotanical studies reveals over 500 medicinal plants in Mindanao,Philippines

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Plant Diversity 2024年第5期46卷 551-564页

作者： Joeime F.Meñiza Monica M.Pasco Jemer A.Alimbon Department of teacher education UM Tagum CollegeTagum City8100Davao del Norte Philippines

Medicinal plants have long been used to treat various diseases in both indigenous and non-indigenous populations of Mindanao,***,we extracted data from ethnobotanical studies to compile a comprehensive list of these medicinal plants and identify how and for what purpose they are most commonly *** identified 530 verified medicinal plant species across 372 genera in 118 *** two most frequently cited species were Euphorbia hirta and Psidium *** most represented family was Fabaceae and the most represented genus was Ficus.A total of 28 medicinal plant species are designated as threatened at the national or global level;of these,11 are endemic to the *** plant preparations most commonly use leaves for oral administration to treat various diseases such as digestive issues,including *** study underscores the need for further ethnobotanical investigations,particularly in areas lacking *** also emphasizes the need for conservation of threatened and endemic medicinal plants to ensure sustainable utilization of this valuable resource.

关键词： Ethnobotany Medicinal plants Mindanao Philippines

Trudinger–Moser Inequalities on a Closed Riemann Surface with a Symmetric Conical Metric

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2263-2284页

作者： Yu FANG Yun Yan YANG College of teacher education Quzhou UniversityQuzhou 324003P.R.China Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This is a continuation of our previous work(*** ***.,20,1295–1324,2020).Let(Σ,g)be a closed Riemann surface,where the metric g has conical singularities at finite *** G is a group whose elements are isometries acting on(Σ,g).Trudinger–Moser inequalities involving G are established via the method of blow-up analysis,and the corresponding extremals are also *** extends previous results of Chen(***.,1990),Iula–Manicini(Nonlinear Anal.,2017),and the authors(2020).

关键词： Trudinger-Moser inequality blow-up analysis conical singularity

Stability Analysis of a Class of Nonlinear Fractional Differential Systems With Riemann-Liouville Derivative

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1883-1885页

作者： Ruoxun Zhang Shiping Yang Shiwen Feng College of teacher education Xingtai UniversityXingtai 054001China College of Physics and Information Engineering Hebei Normal UniversityShijiazhuang 050016China

Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville *** using the Mittag-Leffler function,Laplace transform and the Gronwall-Bellman lemma,one sufficient condition is attained for the asymptotical stability of a class of nonlinear fractional differential systems whose order lies in(0,2).According to this theory,if the nonlinear term satisfies some conditions,then the stability condition for nonlinear fractional differential systems is the same as the ones for corresponding linear *** examples are provided to illustrate the applications of our result.

关键词： Liouville Riemann nonlinear

Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 963-982页

作者： S.JAHANGIRI A.GHORBANPOUR ARANI Z.KHODDAMI MARAGHI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan ***Iran faculty of Engineering Mahallat Institute of Higher EducationMahallat ***Iran

The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is *** shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the *** governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s *** trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are *** present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support.

关键词： free vibration conical shell rotating shell ring support auxetic honeycomb

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

Global warming scenarios for the Eastern Adriatic Sea indicate a higher risk of invasiveness of non-native marine organisms relative to current climate conditions

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Marine Life Science & Technology 2024年第1期6卷 143-154页

作者： Branko Glamuzina Lorenzo Vilizzi Marina Piria Ante Zuljevic Ana Bratos Cetinic Ana Pesic Branko Dragicevic Lovrenc Lipej Marijana Pecarevic Vlasta Bartulovic Sanja Grđan Ivan Cvitkovic Tatjana Dobroslavic Ana Fortic Luka Glamuzina Borut Mavric Jovana Tomanic Marija Despalatovic Domen Trkov Marina Brailo Scepanovic Zoran Vidovic Predrag Simonovic Sanja Matic-Skoko Pero Tutman Department of Applied Ecology University of DubrovnikDubrovnikCroatia Department of Ecology and Vertebrate Zoology Faculty of Biology and Environmental ProtectionUniversity of LodzLodzPoland faculty of Agriculture Department of FisheriesApicultureWildlife Management and Special ZoologyUniversity of ZagrebZagrebCroatia Institute of Oceanography and Fisheries SplitCroatia Institute of Marine Biology University of MontenegroKotorMontenegro National Institute of Biology Marine Biology Station PiranPiranSlovenia teacher education faculty University of BelgradeBelgradeSerbia faculty of Biology University of BelgradeBelgradeSerbia

Globally,marine bioinvasions threaten marine ecosystem structure and function,with the Mediterranean Sea being one of the most affected *** invasions are expected to increase due to climate *** conducted a risk screening of marine organisms(37 fishes,38 invertebrates,and 9 plants),both extant and‘horizon’(i.e.,not present in the area but likely to enter it).Based on expert knowledge for the Eastern Adriatic Sea coasts of Slovenia,Croatia,and Montenegro,screenings were conducted under both current and predicted climate conditions indicating with an increase in sea surface temperature and salinity of the Adriatic Sea together with changes in precipitation *** aims were to:(1)identify non-native extant and horizon marine species that may pose threats to native biodiversity and(2)evaluate the risk of invasiveness of the selected species under current and predicted climate *** the 84 species screened,there was an increase in those ranked as‘high risk’from 33(39.3%)under current climate conditions and to 47(56.0%)under global warming *** those ranked as‘very high’risk,the increase was from 6(7.1%)to 21(25.0%).Amongst the screened species,the already established high-risk species Pacific oyster Magallana gigas and Atlantic blue crab Callinectes sapidus represent a threat to ecosystem *** the under-representation of marine species in the current European Union List,the species we have ranked as high to very high risk should be included.

关键词： AS-ISK Early detection Introduction vectors/pathways Invasive species Rapid response

Research on Risk Identification and Industrial Governance of Digital education Products Based on Data Annotation Technology

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China Communications 2024年第3期21卷 273-282页

作者： Tong Lili Zeng Jia Di Ying Wang Nan faculty of education Beijing Normal University Beijing 100875China China Unicom Beijing 102211China

The social transformation brought aboutby digital technology is deeply impacting various *** education products, with core technologiessuch as 5G, AI, IoT (Internet of Things),etc., are continuously penetrating areas such as teaching,management, and evaluation. Apps, miniprograms,and emerging large-scale models are providingexcellent knowledge performance and flexiblecross-media output. However, they also exposerisks such as content discrimination and algorithmcommercialization. This paper conducts anevidence-based analysis of digital education productrisks from four dimensions: “digital resourcesinformationdissemination-algorithm design-cognitiveassessment”. It breaks through corresponding identificationtechnologies and, relying on the diverse characteristicsof governance systems, explores governancestrategies for digital education products from the threedomains of “regulators-developers-users”.

关键词： digital education products industry governance risk identification