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Arbitrary full-state hybrid projective synchronization for chaotic discrete-time systems via a scalar signal

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Chinese Physics B 2012年第6期21卷 94-99页

作者： Giuseppe Grassi Dipartimento Ingegneria Innovazione universitàdel Salento-73100 Lecce-Italy

In this paper we present a new projective synchronization scheme, where two chaotic （hyperchaotic） discrete-time systems synchronize for any arbitrary scaling matrix. Specifically, each drive system state synchronizes with a linear combination of response system states. The proposed observer-based approach presents some useful features： i） it enables exact synchronization to be achieved in finite time （i.e., dead-beat synchronization）; ii） it exploits a scalar synchronizing signal; iii） it can be applied to a wide class of discrete-time chaotic （hyperchaotic） systems; iv） it includes, as a particular case, most of the synchronization types defined so far. An example is reported, which shows in detail that exact synchronization is effectively achieved in finite time, using a scalar synchronizing signal only, for any arbitrary scaling matrix.

关键词： chaos synchronization full-state hybrid projective synchronization observer-based syn-chronization chaotic discrete-time systems dead beat control attractor scaling

Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management

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Journal of Forestry Research 2019年第1期30卷 143-155页

作者： Rafael M~a Navarro Cerrillo dennis J.Esteves Vieira Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar delgado Serrano depto. Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio Climático.Dendrodat Lab-ERSAF Universidad de Córdoba depto. de Engenharia Florestal Faculdade de Engenharia Florestal Laboratório de Sensoriamento Remoto e Geotecnologia Universidade Federal de Mato Grosso departamento de Ciencias de la Sustentabilidad El Colegio de la Frontera Sur-Unidad Campeche depto. Economía Sociología y Política Agrarias Grupo de Evaluación y Restauración de Sistemas Agrícolas y Forestales-ERSAF Universidad de Córdoba

Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.

关键词： Tropical and temperate forests Social forestry Land uses segmentation OBIA FRAGSTAT

Analysis of Strehl ratio limit with superresolution binary phase filters

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Chinese Optics Letters 2016年第7期14卷 38-41页

作者： Vidal F.Canales Pedro J.Valle Manuel P.Cagigal departamento de física Aplicada Universidad de CantabriaSantander 39005Spain

Several pupil filtering techniques have been developed in the last few years to obtain transverse superresolution （a narrower point spread function core）. Such a core decrease entails two relevant limitations： a decrease of the peak intensity and an increase of the sidelobe intensity. Here, we calculate the Strehl ratio as a function of the core size for the most used binary phase filters. Furthermore, we show that this relation approaches the fundamental limit of the attainable Strehl ratio at the focal plane for any filter. Finally, we show the calculation of the peak-to-sidelobe ratio in order to check the system viability in every application.

关键词： Analysis of Strehl ratio limit with superresolution binary phase filters

Supervision of two fundamental problems in modern fluid dynamics for sparing energy

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Journal of Thermal Science 2009年第2期18卷 97-98页

作者： Jürgen Zierep Institut für Strmungslehre Universitt Karlsruhe

在在接近音速的流动的弄弯的表面的正常吃惊导致一个超级坚定的边界价值问题。在吃惊后面的一个肿块减少机翼和还原剂的 drag 必要精力。在 contrary to 潜水艇的非牛顿的媒介铅的流动决定了边界起始的问题。为这些液体的精力平衡具有... 详细信息

在在接近音速的流动的弄弯的表面的正常吃惊导致一个超级坚定的边界价值问题。在吃惊后面的一个肿块减少机翼和还原剂的 drag 必要精力。在 contrary to 潜水艇的非牛顿的媒介铅的流动决定了边界起始的问题。为这些液体的精力平衡具有为化学工程的大兴趣。

关键词：超音速流震动非牛顿介质流体动力学

Novel four-wing and eight-wing attractors using coupled chaotic Lorenz systems

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Chinese Physics B 2008年第9期17卷 3247-3251页

作者： Giuseppe Grassi Dipartimento di Ingegneria dell’Innovazione Università del Salento

This paper presents the problem of generating four-wing （eight-wing） chaotic attractors. The adopted method consists in suitably coupling two （three） identical Lorenz systems. In analogy with the original Lorenz system, where the two wings of the butterfly attractor are located around the two equilibria with the unstable pair of complex-conjugate eigenvalues, this paper shows that the four wings （eight wings） of these novel attractors axe located around the four （eight） equilibria with two （three） pairs of unstable complex-conjugate eigenvalues.

关键词： chaotic attractors multi-wing attractor coupled Lorenz systems dynamical behaviours

Continuous-time chaotic systems: Arbitrary full-state hybrid projective synchronization via a scalar signal

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Chinese Physics B 2013年第8期22卷 333-338页

作者： Giuseppe Grassi Dipartimento Ingegneria Innovazione Universitàdel Salento-73100 LecceItaly

Relerrlng to contlnuous-Ume claaotlc systems, tills paper presents a new projective syncnromzatlon scheme, wnlcn enables each drive system state to be synchronized with a linear combination of response system states for any arbitrary scaling matrix. The proposed method, based on a structural condition related to the uncontrollable eigenvalues of the error system, can be applied to a wide class of continuous-time chaotic （hyperchaotic） systems and represents a general framework that includes any type of synchronization defined to date. An example involving a hyperchaotic oscillator is reported, with the aim of showing how a response system attractor is arbitrarily shaped using a scalar synchronizing signal only. Finally, it is shown that the recently introduced dislocated synchronization can be readily achieved using the conceived scheme.

关键词： continuous-time chaotic systems chaos synchronization observer-based synchronization scalarsynchronizing signal

Constrained crystals deep convolutional generative adversarial network for the inverse design of crystal structures

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npj Computational Materials 2021年第1期7卷 588-594页

作者： Teng Long Nuno M.Fortunato Ingo Opahle Yixuan Zhang Ilias Samathrakis Chen Shen Oliver Gutfleisch Hongbin Zhang Institute of Materials Science Technische Universität DarmstadtDarmstadtGermany

Autonomous materials discovery with desired properties is one of the ultimate goals for materials science,and the current studies have been focusing mostly on high-throughput screening based on density functional theory calculations and forward modeling of physical properties using machine *** the deep learning techniques,we have developed a generative model,which can predict distinct stable crystal structures by optimizing the formation energy in the latent *** is demonstrated that the optimization of physical properties can be integrated into the generative model as on-top screening or backward propagator,both with their own *** the generative models on the binary Bi-Se system reveals that distinct crystal structures can be obtained covering the whole composition range,and the phases on the convex hull can be reproduced after the generated structures are fully relaxed to the *** method can be extended to multicomponent systems for multi-objective optimization,which paves the way to achieve the inverse design of materials with optimal properties.

关键词： properties crystal inverse

Recent Advances and Challenges Toward Application of Fibers and Textiles in Integrated Photovoltaic Energy Storage devices

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Nano-Micro Letters 2023年第3期15卷 190-247页

作者： Amjid Rafique Isabel Ferreira Ghulam Abbas Ana Catarina Baptista CENIMAT|I3N Department of Materials ScienceSchool of Science and TechnologyNOVA University LisbonCampus de Caparica2829‑516 CaparicaPortugal

Flexible microelectronic devices have seen an increasing trend toward development of miniaturized,portable,and integrated devices as wearable electronics which have the requirement for being light weight,small in dimension,and *** three-dimensional(3D)and two-dimensional(2D)electronics gadgets fail to effectively comply with these necessities owing to their stiffness and large *** have come up with a new family of one-dimensional(1D)flexible and fiber-based electronic devices(FBEDs)comprising power storage,energy-scavenging,implantable sensing,and flexible displays ***,development and manufacturing are still a challenge owing to their small radius,flexibility,low weight,weave ability and integration in textile *** paper will provide a detailed review on the importance of substrates in electronic devices,intrinsic property requirements,fabrication classification and applications in energy harvesting,energy storage and other flexible electronic ***-and textile-based electronic devices for bulk/scalable fabrications,encapsulation,and testing are reviewed and presented future research ideas to enhance the commercialization of these fiber-based electronics devices.

关键词： Flexible electronics Electronic textiles Energy harvesting Supercapacitors Photovoltaic devices

A POSTERIORI ERROR ANALYSIS OF A FULLY-MIXED FINITE ELEMENT METHOD FOR A TWO-DIMENSIONAL FLUID-SOLID INTERACTION PROBLEM

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Journal of Computational Mathematics 2015年第6期33卷 606-641页

作者： Carolina Dominguez Gabriel N. Gatica salim meddahi Instituto de Ciencias Fisicas y Matemdticas facultad de ciencias universidad austral de chile Avenida Eduardo Morales Miranda - Campus isla teja valdivia chile CI2 MA and departamento de Ingenieria Matematica Universidad de concapcion casilla 160 concepcion chile departamento de Matemdticas Facultad de ciencias universidad de oiede calvo satela s/n oviedo espana

In this paper we develop an a posteriori error analysis of a fully-mixed finite element method for a fluid-solid interaction problem in 2D. The media are governed by the elas-todynamic and acoustic equations in time-harmonic regime, respectively, the transmission conditions are given by the equilibrium of forces and the equality of the corresponding normal displacements, and the fluid is supposed to occupy an annular region surrounding the solid, so that a Robin boundary condition imitating the behavior of the sommerfeld condition is imposed on its exterior boundary. Dual-mixed approaches are applied in both domains, and the governing equations are employed to eliminate the displacenent a of the solid and the pressure p of the fluid. In addition, since both transmission conditions become essential, they are enforced weakly by means of two suitable lahrange multipliers The unknowns of the solid and the fluid are then approximated by a conforming galerkin scheme defined in terms of PEERS elements in the solid, Raviart-Thomas of lowest order in the fluid, and continuous piecewise linear functions on the boundary, As the main con-tribution of this work, we derive a reliable and efficient residual-based a posteriori error estimator for the aforedescribed coupled problem. Some numerical results confirming the properties of the estimator are also reported.

关键词： Mixed finite elements Helmholtz equation Elastodynamic equation A poste- riori error analysis