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Arlenea delicata *** ***.,a new ephedroid plant from the Early Cretaceous Crato Formation,Araripe Basin,Northeast Brazil

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Plant Diversity 2024年第3期46卷 362-371页

作者： Alita Maria Neves Ribeiro yong Yang Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de Lima Programa de Pos-graduaçao em Diversidade Biologica e Recursos Naturais Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the Environment159 Longpan RoadNanjing Forestry UniversityNanjing210037China Laboratorio de Paleontologia Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Laboratorio de Estudos da Flora Regional Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil gondwanan Plants Lab Universidade Federal de PernambucoCentro Academico de VitoriaRua Do Alto Reservatorio S/nBela Vista55608-680Vitoria de Santo AntaoPernambucoBrazil Programa de Pos-graduaçao em geociencias(PPgEOC) Universidade Federal de Pernambuco(UFPE)Rua Av.da ArquiteturaS/n°CEP-50740-550Cidade UniversitariaRecifePernambucoBrazil

Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE ***,few ephedroid macrofossils have been reported from South ***,we describe a new plant of the family Ephedraceae,Arlenea delicata *** ***.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive *** has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen *** new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed *** new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the Early ***,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(Enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of Ephedraceae in the Lower Cretaceous.

关键词： Early Cretaceous gnetophytes Arlenea delicata Ephedrales Crato Formation

High-order Soliton Matrix for the Third-order Flow Equation of the gerdjikov-Ivanov Hierarchy Through the Riemann-Hilbert Method

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan ZHU yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The gerdjikov-Ivanov(gI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow gI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow gI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow gI equation is derived.

关键词： gerdjikov-Ivanov hierarchy third-order flow gI equation Riemann-Hilbert method high-order soliton

Homological Transfer between Additive Categories and Higher Differential Additive Categories

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1325-1344页

作者： Xi TANg Zhao yong HUANg School of Science Guilin University of Aerospace TechnologyGuilin 541004P.R.China department of Mathematics Nanjing UniversityNanjing 210093P.R.China

given an additive category C and an integer n≥*** higher differential additive category consists of objects X in C equipped with an endomorphism ϵ_(X)satisfying ϵ_(X)^(n).Let R be a,finite-dimensional basic algebra over an algebraically closed field and T the augmenting functor from the category of finitely generated left R-modules to that of finitely generated left R/(t^(n))-*** is proved that a finitely generated left R-module M isτ-rigid(respectively,(support)τ-tilting,almost completeτ-tilting)if and only if so is T(M)as a left R[t]/(t^(n))-***,R isτm-selfinjective if and only if so is R[t]/(t^(n)).

关键词： Higher differential objects Wakamatsu tilting subcategories g_(ω)-projective modules sup-portτ-tilting modules τ_(m)-selfinjective algebras precluster tilting subcategories

Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： Xiang Zhou Zhi-yong Zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 26.5 gHz-40.0 gHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

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

Long-time Asymptotics for the Reverse Space-time Nonlocal Hirota Equation with decaying Initial Value Problem:without Solitons

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 708-727页

作者： Wei-qi PENg yong CHEN School of Mathematical Sciences East China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this work,we mainly consider the Cauchy problem for the reverse space-time nonlocal Hirota equation with the initial data rapidly decaying in the solitonless *** from the Lax pair,we first construct the basis Riemann-Hilbert problem for the reverse space-time nonlocal Hirota ***,using the approach of deift-Zhou nonlinear steepest descent,the explicit long-time asymptotics for the reverse space-time nonlocal Hirota is *** the reverse space-time nonlocal Hirota equation,since the symmetries of its scattering matrix are different with the local Hirota equation,the v(λ_(i))(i=0,1)would like to be imaginary,which results in theδ_(λi)^(0)contains an increasing t(±Imv(λ_(i)))/2,and then the asymptotic behavior for nonlocal Hirota equation becomes differently.

关键词： Riemann-Hilbert problem reverse space-time nonlocal Hirota equation long-time asymptotics nonlinear steepest descent method

Partial Collapsing degeneration of Floer Trajectories and Adiabatic gluing

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Acta Mathematica Sinica,English Series 2024年第1期40卷 161-249页

作者： yong-geun OH Ke ZHU Center for geometry and Physics Institute for Basic Science(IBS)79 Jigok-ro 127beon-gilNam-guPohang-siGyeongsangbuk-doKorea 37673&POSTECHGyeongsangbuk doKorea department of Mathematics and Statistics Minnesota State UniversityMankatoMN 56001USA

In the present paper,we study partial collapsing degeneration of Hamiltonian-perturbed Floer trajectories for an adiabatic ε-family and its reversal adiabatic gluing,as the prototype of the partial collapsing degeneration of 2-dimensional(perturbed)J-holomorphic maps to 1-dimensional gradient *** consider the case when the Floer equations are S^(1)-invariant on parts of their domains whose adiabatic limit has positive length as ε→0,which we call thimble-flow-thimble *** main gluing theorem we prove also applies to the case with Lagrangian boundaries such as in the problem of recovering holomorphic disks out of pearly *** particular,our gluing theorem gives rise to a new direct proof of the chain isomorphism property between the Morse-Bott version of Lagrangian intersection Floer complex of L by Fukaya-Oh-Ohta-Ono and the pearly complex of L Lalonde and *** also provides another proof of the present authors’earlier proof of the isomorphism property of the PSS map without involving the target rescaling and the scale-dependent gluing.

关键词： Floer trajectory equation partial collapsing degeneration thimble-flow-thimble moduli space adiabatic gluing exponential decay estimates three-interval method

Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective

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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-Heng Du yong-Min Shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-Ri Zhang yong-Hua Shi Bionic Robot Research department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry gradient analysis Real-time detection