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A dark vector resonance at CLIC

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Chinese Physics C 2019年第6期43卷 6-13页

作者： Constanza Callender Alfonso R.Zerwekh Departamento de Física Universidad técnica Federico Santa María and Centro Científico-tecnológico de Valparaíso

One of the main problems in particle physics is to understand the origin and nature of dark matter. An exciting possibility is to consider that dark matter belongs to a new complex but hidden sector. In this paper, we assume the existence of a strongly interacting dark sector consisting of a new scalar doublet and new vector resonances,in accordance with the model recently proposed by our group. Since it was found in the previous work that it is very challenging to find the new vector resonances at the LHC, here we study the possibility of finding them at the future Compact Linear Collider(CLIC) running at■= 3 teV. We consider two distinct scenarios. In the first, when the non-standard scalars are heavy, the dark resonance is intense enough to make its discovery possible at CLIC when the resonance mass is in the range [2000, 3000] GeV. In the second scenario, when the non-standard scalars are light, the new vector boson is too broad to be recognized as a resonance, and is not detectable except when the mass of the scalars is close to(but smaller than) half of the resonance mass and the scale of the dark sector is high. In all positive cases, less than a tenth of the maximum integrated luminosity is needed to reach the discovery level. Finally, we also comment on the mono-Z production.

关键词： vector res on ance dark matter CLIC

Complete fuzzy scheduling and fuzzy earned value management in construction projects

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第1期13卷 56-68页

作者： José Luís PONZ-tIENDA Eugenio PELLICER Víctor YEPES School of Building Engineering Universitat Politècnica de València School of Civil Engineering Universitat Politècnica de València Department of Construction Engineering ICITECHUniversitat Politècnica de València

this paper aims to present a comprehensive proposal for project scheduling and control by applying fuzzy earned *** goes a step further than the existing literature:in the formulation of the fuzzy earned value we consider not only its duration,but also cost and production,and alternatives in the scheduling between the earliest and latest *** mathematical model is implemented in a prototypical construction project with all the estimated values taken as fuzzy *** findings suggest that different possible schedules and the fuzzy arithmetic provide more objective results in uncertain environments than the traditional *** proposed model allows for controlling the vagueness of the environment through the adjustment of the α-cut,adapting it to the specific circumstances of the project.

关键词： Construction Earned value method(EVM) Fuzzy logic Fuzzy set Project management Scheduling

Single π0electro-production in the resonance region with CLAS＊

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Chinese Physics C 2009年第12期33卷 1254-1256页

作者： Kyungseon Joo University of Connecticut 2152 Hillside Road Storrs CT 06269 USA (Universidad tcnica Federico Santa María Valparaíso Chile

We report the analysis status of single π0electroproduction in the resonance region to study the electromagnetic excitation of the nucleon resonances. the study is aimed at understanding of the internal structure and dynamics of the nucleon. the experiment was performed using an unpolarized cryogenic hydrogen target and 2.0 and 5.8 GeV polarized electron beam during the ele and e1-6 run periods with CLAS at Jefferson Lab. the new measurements will produce a data base with high statistics and large kinematic coverage for the hadronic invariant mass （W） up to 2.0 CeV in the momentum transfer （Q2） range of 0.3--6.0 GeV2. Preliminary results will be presented and compared with the various model calculations.

关键词： nucleon resonances electromagnetic transition form factors nucleon structure

Bifurcation Diversity in an Annular Pool Heated from Below:Prandtl and Biot Numbers Effects

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Communications in Computational Physics 2013年第2期13卷 428-441页

作者： A.J.torregrosa S.Hoyas M.J.Pérez-Quiles J.M.Mompò-Laborda CMt-Motores térmicos Universitat Politécnica de ValénciaValencia 46022Spain Instituto Universitario de Matemática Pura y Aplicada Universitat Politécnica de ValénciaValencia 46022Spain

In this article the instabilities appearing in a liquid layer are studied numerically by means of the linear stability *** fluid is confined in an annular pool and is heated from below with a linear decreasing temperature profile from the inner to the outer *** top surface is open to the atmosphere and both lateral walls are *** the Rayleigh number as the only control parameter,many kind of bifurcations appear at moderately low Prandtl numbers and depending on the Biot *** regions on the Prandtl-Biot plane are identified,their boundaries being formed from competing solutions at codimension-two bifurcation points.

关键词： thermocapillary convection Prandtl number Biot number linear stability

A PD-type State-Dependent Riccati Equation With Iterative Learning Augmentation for Mechanical Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1499-1511页

作者： Saeed Rafee Nekoo JoséÁngel Acosta Guillermo Heredia Anibal Ollero GRVC Robotics Lab. Depto de Ingeniería de Sistemas y AutomáticaEscuela Técnica Superior de IngenieríaUniversidad de SevillaSeville 41092Spain

this work proposes a novel proportional-derivative(PD)-type state-dependent Riccati equation(SDRE)approach with iterative learning control(ILC)*** the one hand,the PD-type control gains could adopt many useful available criteria and tools of conventional PD *** the other hand,the SDRE adds nonlinear and optimality characteristics to the controller,i.e.,increasing the stability *** advantages with the ILC correction part deliver a precise control law with the capability of error reduction by *** SDRE provides a symmetric-positive-definite distributed nonlinear suboptimal gain K(x)for the control input law u=–R–1(x)Bt(x)K(x)*** sub-blocks of the overall gain R–1(x)Bt(x)K(x),are not necessarily symmetric positive definite.A new design is proposed to transform the optimal gain into two symmetric-positive-definite gains like PD-type controllers as u=–KSP(x)e–KSD(x)?.the new form allows us to analytically prove the stability of the proposed learning-based controller for mechanical systems;and presents guaranteed uniform boundedness in finite-time between learning *** symmetric PD-type controller is also developed for the state-dependent differential Riccati equation(SDDRE)to manipulate the final *** SDDRE expresses a differential equation with a final boundary condition,which imposes a constraint on time that could be used for finitetime ***,the availability of PD-type finite-time control is an asset for enhancing the conventional classical linear controllers with this *** learning rules benefit from the gradient descent method for both regulation and tracking *** of the advantages of this approach is a guaranteed-stability even from the first loop of learning.A mechanical manipulator,as an illustrative example,was simulated for both regulation and tracking *** experimental validation was done to show the capability of the system in practice by the implementation of the proposed metho

关键词： Closed-loop iterative learning control(ILC) PD-type SDRE SDDRE symmetric

Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

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Journal of Mountain Science 2012年第3期9卷 372-384页

作者： Alicia Ledo Sonia Condés Iciar Alberdi Universidad Politécnica de Madrid.Escuela técnica Superior de Ingenieros de Montes.Ciudad Universitaria sn.28040MadridSpain CIFOR-INIA Ctra.de La Corua Km 7.5 28040MadridSpain

Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. the tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. the biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the "Bosque de Neblina de Cuyas", in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. the values obtained were compared with other cloud forests. the study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. the high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.

关键词： Andean Range Biodiversity Dead wood Montane forest Species composition Stand structure tropical forest

Combined heat and mass transfer by mixed convection MHD flow along a porous plate with chemical reaction in presence of heat source

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Applied Mathematics and Mechanics(English Edition) 2010年第10期31卷 1217-1230页

作者： J.ZUECO S.AHMED EtS Ingeniería Industrial Departamento de Ingeniería Térmicay FluidosUniversidad Politécnica de Cartagena Fluid Dynamics Research Department of MathematicsGoalpara College

An exact and a numerical solutions to the problem of a steady mixed convective MHD flow of an incompressible viscous electrically conducting fluid past an infinite vertical porous plate with combined heat and mass transfer are presented.A uniform magnetic field is assumed to be applied transversely to the direction of the flow with the consideration of the induced magnetic field with viscous and magnetic dissipations of *** porous plate is subjected to a constant suction velocity as well as a uniform mixed stream *** governing equations are solved by the perturbation technique and a numerical *** analytical expressions for the velocity field,the temperature field,the induced magnetic field,the skin-friction,and the rate of heat transfer at the plate are *** numerical results are demonstrated graphically for various values of the parameters involved in the *** effects of the Hartmann number,the chemical reaction parameter,the magnetic Prandtl number,and the other parameters involved in the velocity field,the temperature field,the concentration field,and the induced magnetic field from the plate to the fluid are *** increase in the heat source/sink or the Eckert number is found to strongly enhance the fluid velocity *** induced magnetic field along the x-direction increases with the increase in the Hartmann number,the magnetic Prandtl number,the heat source/sink,and the viscous *** is found that the flow velocity,the fluid temperature,and the induced magnetic field decrease with the increase in the destructive chemical *** of the study arise in the thermal plasma reactor modelling,the electromagnetic induction,the magnetohydrodynamic transport phenomena in chromatographic systems,and the magnetic field control of materials processing.

关键词： MHD perturbation technique network simulation method Eckert number mixed convection induced magnetic field viscous dissipation heat source/sink

Behavior of materials for earth and rockfill dams:Perspective from unsaturated soil mechanics

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 1-39页

作者： Eduardo E.ALONSO Rafaela CARDOSO Universidad Politécnica de Cataluña BarcelonaSpain Instituto Superior técnico LisbonPortugal

the basis of the design of earth and rockfill dams is focused on ensuring the stability of the structure under a set of conditions expected to occur during its *** mechanical and hydraulic conditions must be considered since pore pressures develop during construction,after impoundment and in *** instability phenomena caused by transient flow and internal erosion must be *** prediction of the hydromechanical behavior of traditional and non-traditional materials used in the construction of dams is therefore *** materials used for dam’s construction cover a wide range from clayey materials to *** a broad sense they are compacted materials and therefore unsaturated materials.A summary of the current level of knowledge on the behavior of traditional materials used in the construction of dams is presented in the *** compacted materials(with a significant clay fraction),rockfill and compacted soft rocks are studied with more *** latter are non-traditional *** are analysed because their use,as well as the use of mixtures of soil and rock,is becoming more necessary for sustainability reasons.

关键词： dams unsaturated soil mechanics suction rockfill clayey soil mixture

Comparing AdS/CFt dipole model to HERA F_2 data

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Chinese Physics C 2010年第9期34卷 1421-1424页

作者：吕准 Department of Physics Southeast University Departamento de Física y Centro de Estudios Subatómicos Universidad Técnica Federico Santa María

We apply an AdS/CFt-inspired color-dipole model which contains only three free parameters to describe the HERA data for the inclusive structure function F 2 at small Bjorken-x and *** found that the saturation scale in our AdS/CFt-based parameterization varies in the range of 1 ÷ 3 GeV becoming independent of energy/Bjorken-x at very small *** leads to the prediction of x-independence of the structure functions at very small *** the fitted parameters in our model,the predictions for F 2,longitudinal structure function,charm structure function and total photo-production cross-sections in the kinematic regions of future experiments can be given.

关键词： color dipole model AdS/CFt correspondence structure function saturation scale