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Light losses in hollow, prismatic light guides related to prism defects: a transmittance model

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Chinese Optics Letters 2015年第9期13卷 68-72页

作者： Berta García-fernández Daniel Vázquez-moliní Antonio álvarez fernández-Balbuena Angel García-Botella Juan Carlos m.r.ínez Antón Department of Optics Faculty of Optics and Optometry University Complutense of Madrid Department of Physics Applied to Natural resources School of Forestry EngineeringPolytechnic University of Madrid

Hollow, cylindrical, prismatic light guides （CPLGs） are optical components that, using total internal reflection （TIr）, are able to transmit high-diameter light beams in daylight and artificial lighting applications without relevant losses. It is necessary to study the prism defects of their surfaces to quantify the behavior of these optical components. In this Letter, we analyze a CPLG made of a transparent dielectric material. Scanning electron microscopy （SEm） and the topographic optical profilometry by absorption in fluids （TOPAF） imaging tech- nique are conducted to determine if there are defects in the corners of the prisms. A model for light guide trans- mittance that is dependent on prism defects is proposed. Finally, a simulation and an experimental study are carried out to check the validity of the proposed model.

关键词： Light losses in hollow a transmittance model prismatic light guides related to prism defects

Anther and pollen development:A conserved developmental pathway

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Journal of Integrative Plant Biology 2015年第11期57卷 876-891页

作者： José fernndez Gmez Behzad Talle Zoe A Wilson School of Biosciences University of NottinghamSutton Bonington Campus

Pollen development is a critical step in plant development that is needed for successful breeding and seed formation. manipulation of male fertility has proved a useful trait for hybrid breeding and increased crop yield. However, although there is a good understanding developing of the molecular mechanisms of anther and pollen anther development in model species, such as Arabidopsis and rice, little is known about the equivalent processes in important crops. Nevertheless the onset of increased genomic information and genetic tools is facilitating translation of information from the models to crops, such as barley and wheat; this will enable increased understanding and manipulation of these pathways for agricultural im.r.vement.

关键词： Anther Arabdiopsis cereals comparative biology pollen

Parameter Control of Genetic Algorithms by Learning and Simulation of Bayesian Networks——A Case Study for the Optimal Ordering of Tables

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Journal of Computer Science & Technology 2013年第4期28卷 720-731页

作者： Concha Bielza Juan A. fernndez del Pozo Pedro Larranaga Computational Intelligence Group Department of Artificial IntelligenceTechnical University of Madrid

Parameter setting for evolutionary algorithms is still an important issue in evolutionary computation. There are two main approaches to parameter setting： parameter tuning and parameter control. In this paper, we introduce self-adaptive parameter control of a genetic algorithm based on Bayesian network learning and simulation. The nodes of this Bayesian network are genetic algorithm parameters to be controlled. Its structure captures probabilistie conditional （in）dependence relationships between the parameters. They are learned from the best individuals, i.e., the best configurations of the genetic algorithm. Individuals are evaluated by running the genetic algorithm for the respective parameter configuration. Since all these runs are time-consuming tasks, each genetic algorithm uses a small-sized population and is stopped before convergence. In this way promising individuals should not be lost. Experiments with an optimal search problem for simultaneous row and column orderings yield the same optima as state-of-the-art methods but with a sharp reduction in computational time. m.r.over, our approach can cope with as yet unsolved high-dimensional problems.

关键词： genetic algorithm estimation of distribution algorithm parameter control parameter setting Bayesian network

D_(s_1)(2536)^+ decays and the structure of P-wave charmed strange mesons

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Chinese Physics C 2010年第9期34卷 1408-1410页

作者： J.Segovia D.r.Entem F.fernández Nuclear Physics Group University of Salamanca IUFFym University of Salamanca

We calculate the D s 1 （2536） ^＋ decays into D＊K channels,including the decay D s 1 （2536）＋ → D ＋ π-K ＋ through a virtual D＊0 in a constituent quark *** and S/D amplitudes ratio are in agreement with the ... 详细信息

关键词： meson spectra meson decays non relativistic quark models multiquarks

Influence of parameters on the microstructure of a duplex stainless steel joint welded by a GmAW welding process

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Progress in Natural Science:materials International 2022年第4期32卷 415-423页

作者： Sandra Chacón-fernández Antonio Portolés García Gerardo romaní Labanda Universidad Politécnica de madrid Escuela Técnica Superior de Ingenieros Industriales UPM

Duplex stainless steels（DSSs） are widely used in industry for their desirable properties. Any fusion welding technique modifies the microstructure and, consequently, the properties of the material. This paper presents a parametric study of the variables that determine the energy contribution（current, voltage and welding speed） and the structural modifications produced during gas metal arc welding. The analysis com.r.ses metallographic study,phase balance, dimensioning of the weld beads and tensile and hardness tests. The influence of the variables studied on the thermal cycles obtained（temperatures reached and cooling rate） was determined by using a finite element model. The results showed that, in addition to the indicated parameters, the parameter power transfer per volume（W/m3） and the geometry in the bead must be controlled due to their influence on the heat flow distribution and phase balance.

关键词： Welding Heat input GmAW Duplex stainless steels (DSS) Finite element model (FEm)

Elastic Sm.r. Contracts in Blockchains

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IEEE/CAA Journal of Automatica Sinica 2021年第12期8卷 1901-1912页

作者： Schahram Dustdar Pablo fernández Josém.r.a García Antonio ruiz-Cortés Distributed Systems Group Vienna University of TechnologyWien 1040Austria Sm.r. Computer Systems research and Engineering Lab Research Institute of Computer EngineeringUniversity of SevillaSevilla 41012Spain

In this paper,we deal with questions related to blockchains in complex Internet of Things(IoT)-based *** ecosystems are typically composed of IoT devices,edge devices,cloud computing software services,as well as people,who are decision makers in scenarios such as sm.r. *** decisions related to analytics can be based on data coming from IoT sensors,software services,and ***,they are typically based on different levels of abstraction and *** poses a number of challenges when multiple blockchains are used together with sm.r. *** work proposes to apply our concept of elasticity to sm.r. contracts and thereby enabling analytics in and between multiple blockchains in the context of *** propose a reference architecture for Elastic Sm.r. Contracts and evaluate the approach in a sm.r. city scenario,discussing the benefits in terms of performance and self-adaptability of our solution.

关键词： Blockchain elasticity Internet of Things(IoT) sm.r. cities sm.r. contracts virtual chains

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVArI m.r.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,num.r.cal simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

Adenosine A2A-dopamine D2 receptor heterom.r. operate striatal function:impact on Parkinson's disease pharmacotherapeutics

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Neural regeneration research 2018年第2期13卷 241-243页

作者： víctor fernández-duenas sergi ferré francisco ciruela unitat de farmacologia departament patologia i terapèutica experimentalfacultat de medicinaidibelluniversitat de barcelonal’hospitalet de llobregatBarcelonaSpain institut de neurociències universitat de barcelonaBarcelonaSpain integrative neurobiology section national institute on drug abuseintramural research programnational institutes of healthBaltimoreMDUSA

The basal ganglia （BG） assemble a series of deep gray matter structures forming recurrent loops that include the cortex and thalamus, and that participate in the regulation of a plethora of brain functions, including elicitation and learning of reward-and aversive stimuli-associated behaviors, motor activity control and sensorimotor gating （Brom- berg-m.r.in et al., 2010）.

关键词： A(2A) rECEPTOrS BASAL GANGLIA DOPAmINE-D-2

Transport coefficients of a massive pion gas

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Chinese Physics C 2010年第9期34卷 1453-1455页

作者： D.fernández-Fraile A.Gómez Nicola Institut für Theoretische Physik Johann Wolfgang Goethe-Universitt Departamento de Física Teórica II Universidad Complutense

We review our main results concerning the transport coefficients of a light meson gas,in particular we focus on the case of a massive pion *** order results according to the chiral power-counting are presented for the DC electrical conductivity,thermal conductivity,shear viscosity,and bulk *** also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD,as well as the relation between unitarity and a minimum of the quotient η/s near the phase transition.

关键词： transport coefficients heavy-ion collisions Chiral Perturbation Theory