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Rational Schur Superalgebras

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Algebra Colloquium 2024年第2期31卷 209-220页

作者： Andrew Riesen Shun-Jen Cheng department of mathematical and statistical sciences University of Alberta 1132489 Ave NWEdmontonAlbertaCanada 不详

We develop and study the generalization of rational Schur algebras to the super *** to the classical case,this provides a new method for studying rational supermodules of the general linear supergroup GL(m|n).Furthermore,we establish a Schur-Weyl duality result for rational Schur superalgebras and conclude that under certain conditions these objects will be semisimple.

关键词： Schur algebra supermathematics general linear supergroup

Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN B.MAHANTHESH G.LORENZINI Center for mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of mathematical and statistical sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-based Ag-Mg O hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variable fluid properties affect the dynamics and heat transfer features is studied by Reynolds's linearized model for variable viscosity and Chiam's model for variable thermal *** single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressibility condition.A self-similar model is developed by the Lie-group scaling transformations,and the subsequent self-similar equations are then solved *** influence of variable fluid parameters on both swirling and non-swirling flow cases is ***,the Nusselt number for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hybrid nanofluid cone-disk system laminar flow variable fluid property Nusselt number

On hypersurfaces of H2×H2

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science China Mathematics 2024年第2期67卷 339-366页

作者： Dong Gao Hui Ma Zeke Yao School of science Beijing University of Civil Engineering and Architecture department of mathematical sciences Tsinghua University

In this paper, we study hypersurfaces of H2× H2. We first classify the hypersurfaces with constant principal curvatures and constant product angle functions. Then we classify homogeneous hypersurfaces and isoparametric hypersurfaces, respectively. Finally, we classify the hypersurfaces with at most two distinct constant principal curvatures, as well as those with three distinct constant principal curvatures under some additional conditions.

关键词： constant principal curvature homogeneous hypersurface isoparametric hypersurface 53C42 53B25 53C40

Dynamical behaviors of a constant prey refuge ratio-dependent prey-predator model with Allee and fear effects

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International Journal of Biomathematics 2024年第1期17卷 227-250页

作者： Soumitra Pal Pijush Panday Nikhil Pal A.K.Misra Joydev Chattopadhyays department of Mathematics Institute of science Banaras Hindu University Varanasi 221005India department of mathematical and statistical sciences University of Alberta EdmontonAB T6G 2G1Canada department of Mathematics Visva-Bharati Santiniketan 731235India Agricultural and Ecological Research Unit Indian statistical Institute 203 B.T.RoadKolkata 700108India

In this paper,we consider a nonlinear ratio-dependent prey-predator model with constant prey refuge in the prey *** Allee and fear phenomena are incorporated explicitly in the growth rate of the prey *** qualitative behaviors of the proposed model are investigated around the equilibrium points in *** bifurcation including its direction and stability for the model is also *** observe that fear of predation risk can have both stabilizing and destabilizing effects and induces bubbling phenomenon in the *** is also observed that for a fixed strength of fear,an increase in the Allee parameter makes the system unstable,whereas an increase in prey refuge drives the system toward ***,higher values of both the Allee and prey refuge parameters have negative impacts and the populations go to ***,we explore the variation of densities of the populations in different bi-parameter spaces,where the coexistence equilibrium point remains *** simulations are carried out to explore the dynamical behaviors of the system with the help of MATLAB software.

关键词： Predator-prey system Allee effect fear effect prey refuge bifurcation population density

Gender-Based Analysis of User Reactions to Facebook Posts

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Big Data Mining and Analytics 2024年第1期7卷 75-86页

作者： Yassine El Moudene Jaafar Idrais Rida El Abassi Abderrahim Sabour mathematical Engineering and Computer science Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco department of Computer science mathematical−High School of Technology Ibn Zohr UniversityAgadir 8706Morocco

Online Social Networks(OSNs)are based on the sharing of different types of information and on various interactions(comments,reactions,and sharing).One of these important actions is the emotional reaction to the *** diversity of reaction types available on Facebook(namely FB)enables users to express their feelings,and its traceability creates and enriches the users’emotional identity in the virtual *** paper is based on the analysis of 119875012 FB reactions(Like,Love,Haha,Wow,Sad,Angry,Thankful,and Pride)made at multiple levels(publications,comments,and sub-comments)to study and classify the users’emotional behavior,visualize the distribution of different types of reactions,and analyze the gender impact on emotion *** of these can be achieved by addressing these research questions:who reacts the most?Which emotion is the most expressed?

关键词： profiling knowledge extraction data mining emotion mining social media data crawling Facebook reactions gender

Research on Credit Default Swaps Pricing Considering Moral Hazard Incentive under Reduce-Form Model

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Journal of Systems science and Systems Engineering 2024年第3期33卷 311-329页

作者： Liang Wu Kangjie He Zhe Guo School of mathematical science Henan Institute of Science and TechnologyXinxiang453003China Public Front Office department Industrial and Commercial Bank of ChinaZhengzhou450000China

Equilibrium pricing of credit default swaps(CDS)promotes efficient identification of credit risk in the market,which in turn leads to efficient allocation of ***,even when CDS have been priced in equilibrium,i.e.,when premiums are equal to anticipated payments,the moral hazard incentives of CDS buyers increase with CDS ***,it becomes an interesting research direction to study the impact of moral hazard incentives on the trading mechanism or pricing of derivatives(CDS).Most of the existing literature on the impact of moral hazard incentives in CDS pricing on derivatives trading mechanisms takes a macro perspective and focuses on the agreement risk *** literature exploring the analysis of the impact of moral hazard on the probability of agreement default from a micro perspective is not yet *** this in mind,this paper focuses on the mechanisms by which“fraud”,an extreme manifestation of micro-moral hazard incentives,affects the probability of *** paper introduces for the first time the concept of“claiming fraud”by credit protection buyers,which is different from the macro perspective of moral hazard incentives,and thus defines a specific extreme form of moral hazard ***,to address the intrinsic feature of the lack of economic explanatory power of the reduce-form model,this paper introduces a moral hazard incentive factor into the reduce-form model,and proposes a moral hazard state variable as a function of the asset value of the reference entity,which gives the reduce-form model strong economic explanatory power,and the default predictability is reduced by the description of the reduce-form *** terms of the object of study,this paper considers the issue of moral hazard incentives in the presence of claiming fraud in two reference entities to further explore the impact of moral hazard incentives on default protection at the micro level in terms of cyclic ***,based on the

关键词： Financial engineering moral hazard incentive claiming fraud reduce-form model probability of default calculation CDS pricing

Relation Between the Eventual Continuity and the E-property for Markov-Feller Semigroups

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 1-16页

作者： Yong Liu Zi-yu Liu LMAM School of Mathematical SciencePeking UniversityBeijing100871China

We investigate some relations between two kinds of semigroup regularities, namely the e-property and the eventual continuity, both of which contribute to the ergodicity for Markov processes on Polish *** precisely, we prove that for Markov-Feller semigroup in discrete time and stochastically continuous MarkovFeller semigroup in continuous time, if there exists an ergodic measure whose support has a nonempty interior,then the e-property is satisfied on the interior of the support. In particular, it implies that, restricted on the support of each ergodic measure, the e-property and the eventual continuity are equivalent for the discrete-time and the stochastically continuous continuous-time Markov-Feller semigroups.

关键词： Markov-Feller semigroup ergodicity e-property eventual continuity

A chaotic hierarchical encryption/watermark embedding scheme for multi-medical images based on row-column confusion and closed-loop bi-directional diffusion

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Chinese Physics B 2024年第2期33卷 228-237页

作者：张哲祎牟俊 Santo Banerjee 曹颖鸿 School of Information science and Engineering Dalian Polytechnic UniversityDalian 116034China department of mathematical sciences Politecnico di TorinoTorino 10129Italy

Security during remote transmission has been an important concern for researchers in recent *** this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is designed,and a multiimage encryption(MIE)algorithm with row and column confusion and closed-loop bi-directional diffusion is adopted in the *** ensuring secure communication of medical image information,people with different security levels have different levels of decryption keys,and differentiated visual effects can be obtained by using the strong sensitivity of chaotic *** highest security level can obtain decrypted images without watermarks,and at the same time,patient information and copyright attribution can be verified by obtaining watermark *** experimental results show that the scheme is sufficiently secure as an MIE scheme with visualized differences and the encryption and decryption efficiency is significantly improved compared to other works.

关键词： chaotic hierarchical encryption multi-medical image encryption differentiated visual effects row-column confusion closed-loop bi-directional diffusion transform domain watermark embedding

On the superconvergence of a WG method for the elliptic problem with variable coefficients

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science China Mathematics 2024年第8期67卷 1899-1910页

作者： Junping Wang Xiaoshen Wang Xiu Ye Shangyou Zhang Peng Zhu Division of mathematical sciences National Science FoundationAlexandriaVA 22314USA department of Mathematics University of Arkansas at Little RockLittle RockAR 72204USA department of mathematical sciences University of DelawareNewarkDE 19716USA College of Data science Jiaxing UniversityJiaxing 314001China

This article extends a recently developed superconvergence result for weak Galerkin(WG)approximations for modeling partial differential equations from constant coefficients to variable *** superconvergence features a rate that is two orders higher than the optimal-order error estimates in the usual energy and L^(2)*** extension from constant to variable coefficients for the modeling equations is highly *** underlying technical analysis is based on a sequence of projections and *** results confirm the superconvergence theory for second-order elliptic problems with variable coefficients.

关键词： weak Galerkin finite element methods superconvergence second-order elliptic problems stabilizerfree