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Gibbs sampling based distributed OFDMA resource allocation

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Science China(Information Sciences) 2014年第4期57卷 18-29页

作者： garcia Virgile CHEN Chung Shue ZHOU YiQing SHI JingLin Wireless Technology Research Center Institute of Computing Technology Chinese Academy of Sciences Beijing Key Laboratory of Mobile Computing and Pervasive Device

In this article,we present a distributed resource and power allocation scheme for multiple-resource wireless cellular *** global optimization of multi-cell multi-link resource allocation problem is known to be NP-hard in the general *** use Gibbs sampling based algorithms to perform a distributed optimization that would lead to the global optimum of the *** objective of this article is to show how to use the Gibbs sampling(GS)algorithm and its variant the Metropolis-Hastings(MH)*** also propose an enhanced method of the MH algorithm,based on a priori known target state distribution,which improves the convergence speed without increasing the ***,we study different temperature cooling strategies and investigate their impact on the network optimization and convergence *** results have also shown the effectiveness of the proposed methods.

关键词： radio resource allocation power control interference management distributed optimization Gibbs sampling Metropolis-Hastings

Seismic risk assessment for developing countries: Pakistan as a case study

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 787-804页

作者： Shaukat A.Khan Kypros Pilakoutas Iman Hajirasouliha Reyes garcia Maurizio Guadagnini Dept. of Civil Engineering Abasyn University Dept. of Civil and Structural Engineering The University of Sheffield

Modern Earthquake Risk Assessment（ERA） methods usually require seismo-tectonic information for Probabilistic Seismic Hazard Assessment（PSHA） that may not be readily available in developing countries. To bypass this drawback, this paper presents a practical event-based PSHA method that uses instrumental seismicity, available historical seismicity, as well as limited information on geology and tectonic setting. Historical seismicity is integrated with instrumental seismicity to determine the long-term hazard. The tectonic setting is included by assigning seismic source zones associated with known major faults. Monte Carlo simulations are used to generate earthquake catalogues with randomized key hazard parameters. A case study region in Pakistan is selected to demonstrate the effectiveness of the method. The results indicate that the proposed method produces seismic hazard maps consistent with previous studies, thus being suitable for generating such maps in regions where limited data are available. The PSHA procedure is developed as an integral part of an ERA framework named EQRAM. The framework is also used to determine seismic risk in terms of annual losses for the study region.

关键词： recycled concrete frame-shear wall concealed bracings shaking table test nonlinear time-history responseanalysis

Dendritic Growth, Eutectic Features and Their Effects on Hardness of a Ternary Sn–Zn–Cu Solder Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 528-540页

作者： Bismarck Luiz Silva Rodrigo Valenzuela Reyes Amauri garcia JoséEduardo Spinelli Department of Materials Engineering Federal University of Rio Grande do Norte-UFRNNatalRN 59078-970Brazil Department of Materials Engineering Federal University of Sao Carlos-UFSCarSao CarlosSP 13565-905Brazil Department of Manufacturing and Materials Engineering University of CampinasUNICAMPCampinasSP 13083-860Brazil

The present investigation is based on the results of a directionally solidified （DS） Sn-9 wt%Zn-2 wt%Cu alloy, including primary/secondary/tertiary dendrite arm spacings of the Sn-rich matrix, the morphologies of the eutectic mixture and the corresponding interphase spacing, the nature and proportion of the Cu-Zn intermetallic compound （IMC）. The main purpose is to establish interrelations of these microstructure features with experimental solidification thermal parameters, such as cooling rates and growth rates （v）, macrosegregation and hardness. Such interrelations are interesting for both industry and academy since they represent a tool permitting the preprogramming of final properties based on the design of the microstructure. In the case of Sn-Zn-Cu alloys, hardly anything is known about the combined effects of the length scale of the microstructure and fraction and distribution of the primary IMC on hardness. The alloy microstructure is composed of a β-Sn dendritic region, surrounded by a eutectic mixture of α-Zn and β-Sn phases and the γ-Cu5Zn8 IMC. The eutectic interphase spacing varies in the range 1.2-3.6 μm, with the α-Zn phase having a globular morphology for ν 〉 0.5 mm/s and a needle-like morphology for ν 〈 0.3 mm/s. A modified Hall-Petch-type experimental expression relating hardness to the interphase spacing is proposed.

关键词： Sn-Zn-Cu solder alloy Solidification Microstructure Eutectic morphology Hardness

Maneuvering Angle Rigid Formations With Global Convergence Guarantees

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1464-1475页

作者： Liangming Chen Zhiyun Lin Hector garcia de Marina Zhiyong Sun Mir Feroskhan School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Computer Architecture and Technology and also with CITICUniversity of Granada18014 GranadaSpain Department of Electrical Engineering Eindhoven University of Technology5600 MB Eindhoventhe Netherlands

Angle rigid multi-agent formations can simultaneously undergo translational,rotational,and scaling maneuvering,therefore combining the maneuvering capabilities of both distance and bearing rigid ***,maneuvering angle rigid formations in 2D or 3D with global convergence guarantees is shown to be a challenging problem in the existing literature even when relative position measurements are *** by angle-induced linear equations in 2D triangles and 3D tetrahedra,this paper aims to solve this challenging problem in both 2D and3D under a leader-follower *** the 2D case where the leaders have constant velocities,by using local relative position and velocity measurements,a formation maneuvering law is designed for the followers governed by double-integrator *** the leaders have time-varying velocities,a sliding mode formation maneuvering law is proposed by using the same *** the 3D case,to establish an angle-induced linear equation for each tetrahedron,we assume that all the followers'coordinate frames share a common Z ***,a formation maneuvering law is proposed for the followers to globally maneuver Z-weakly angle rigid formations in *** extension to Lagrangian agent dynamics and the construction of the desired rigid formations by using the minimum number of angle constraints are also *** examples are provided to validate the effectiveness of the proposed algorithms.

关键词： Index Terms—Angle rigid formations formation control formation maneuvering global convergence multi-agent systems

Hybrid magnetorheological elastomers enable versatile soft actuators

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npj Computational Materials 2022年第1期8卷 1546-1559页

作者： Miguel Angel Moreno-Mateos Mokarram Hossain Paul Steinmann Daniel garcia-Gonzalez Department of Continuum Mechanics and Structural Analysis Universidad Carlos III de MadridAvda.de la Universidad 3028911LeganésMadridSpain Zienkiewicz Centre for Computational Engineering Faculty of Science and EngineeringSwansea UniversitySA18ENSwanseaUK Institute of Applied Mechanics University of Erlangen-NurembergEgerland Str.5ErlangenGermany Glasgow Computational Engineering Centre School of EngineeringUniversity of GlasgowG128QQGlasgowUK

Recent advances in magnetorheological elastomers(MREs)have posed the question on whether the combination of both soft-and hard-magnetic particles may open new routes to design versatile multifunctional ***,we conceptualise ultra-soft hybrid MREs(≈1–10 kPa stiffness)combining experimental and computational ***,a comprehensive experimental characterisation is *** results unravel that the magneto-mechanical performance of hybrid MREs can be optimised by selecting an adequate mixing ratio between ***,a multi-physics computational framework provides insights into the synergistic magneto-mechanical interactions at the *** particles amplify the magnetisation and hard particles contribute to torsional *** numerical results suggest that the effective response of hybrid MREs emerges from these intricate ***,we uncover exciting possibilities to push the frontiers of MRE *** are demonstrated by simulating a bimorph beam that provides actuation flexibility either enhancing mechanical bending or material stiffening,depending on the magnetic stimulation.

关键词： versatile magneto enable

A Study on the Density of Agglomerates Prepared from Cork Wastes

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Journal of Materials Science & Technology 2003年第1期19卷 46-50页

作者： A.Macias-garcia A.Diaz-Parralejo 等 AreaofMaterialsScienceandMetallurgyEngineering FacultyofIndustrialEngineeringUniversityofExtremadure06071BadaiozSpain AreaofMaterialsScienceandMetallurgyEngineering FacultyofIndustrialEngineeringU

The density of black regranulate (BR) of cork and of black agglomerate (BA) and composite agglomerate (CA) prepared fromsuch a waste by different methods was investigated. The preparation of the agglomerates was undertaken by controlling thespecimen thickness for BA and the particle size for BR and the binder dosage for CA. The mass changes produced in theoven-drying treatment at 376.15 K of the agglomerates and in their subsequent stabilization under ambient conditions werealso analyzed. The density was determined by standard methods. For BR, the bulk density first decreased and then increasedwith decreasing particle size. It was much lower than the apparent density of the agglomeration products of cork. Although toa lesser extent, the density was also lower for BA than for CA. It was higher for the smaller thickness specimens of BA. In thecase of CA, the density followed the same variation trends as for BR. Furthermore it increased significantly with the increasein resin dosage. This resulted in a noticeable increase in the weight loss during the oven-drying and in a significant decreasein the degree of moisture adsorption during the stabilization period of the agglomerate.

关键词： Cork Agglomerates Density

The relationship between fire severity and burning efficiency for estimating wildfire emissions in Mediterranean forests

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林业研究:英文版 2023年第5期34卷 1195-1206页

作者： Bountouraby balde cristina Vega-garcia Pere Joan Gelabert Aitor Ameztegui Marcos Rodrigues Department of Agriculture and Forest Engineering University of LleidaAv.Alcalde Rovira Roure19125198 LleidaSpain Department of Geography and Land Management University of ZaragozaPedro Cerbuna 1250009 SaragossaSpain

Forests are exposed to changing climatic conditions reflected by increasing drought and heat waves that increase the risk of wildfire ignition and *** variables such as rain and wind as well as vegetation structure,land configuration and forest management practices are all factors that determine the burning potential of *** assessment of emissions released by vegetation combustion is essential for determining greenhouse gases and air *** estimation of wildfire-related emissions depends on factors such as the type and fraction of fuel(i.e.,live biomass,ground litter,dead wood)consumed by the fire in a given area,termed the burning *** approaches estimate live burning efficiency from optical remote sensing *** study used a data-driven method to estimate live burning efficiency in a Mediterranean *** severity estimations from Lands at imagery(dNBR),which relate to fuel consumption,and quantitative field data from three national forest inventory data were combined to establish the relationship between burning severity and live burning *** proxies explored these relationships based on dNBR interval classes,as well as regres sion *** correlation results between live burning efficiency and dNBR for conifers(R=0.63)and broad-leaved vegetation(R=0.95)indicated ways for improving emissions *** estimations by severity class(low,moderate-low,moderate-high,and high)are provided for conifers(0.44-0.81)and broad-leaves(0.64-0.86),and regression models for the live fraction of the tree canopy susceptible to burning(7 branches,and leaves).The live burning efficiency values by severity class were higher than previous studies.

关键词： Forest wildfires Emissions Greenhouse gases Satellite images

Evaluation of VEGF gene polymorphisms and proliferative diabetic retinopathy in Mexican population

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 135-139页

作者： Roberto Gonzalez-Salinas Maria C garcia-Gutierrez Gerardo garcia-Aguirre Virgilio Morales-Canton Raul Velez-Montoya Vidal R Soberon-Ventura Victoria Gonzalez Rodrigo Lechuga Pablo garcia-Solis David G garcia-Gutierrez Marco Vinicio garcia-Solis Manuel Saenz de Viteri Juan C Solis-S Biomedical Research Department Autonomous University of QueretaroQueretaro 76170Mexico Retina Department Asociation to Prevent Blindness in MexicoMexico City 04030Mexico Research Department Asociation to Prevent Blindness in MexicoMexico City 04030Mexico Retina Department General Hospital of Queretaro(ISSSTE)Queretaro 76000Mexico Universidad La Salle School of Medicine Mexico City 06140Mexico

AIM： To assess if the included vascular endothelial growth factor （VEGF） polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus （T2DM）. METHODS： A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study （ETDRS） standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype ***： In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher’s exact test was performed for rs3025021 [OR （95% CI）=0.44（0.08-2.2）; P=0.25] and rs2010963 [OR （95% CI）=0.63（0.25-1.6）; P=0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows： rs3025021 vs rs3025035： D’=1.0, r2=0.1043, P≤0.0001; rs3025021 vs rs2010963： D’=0.442, r2=0.0446, P=0.149; rs3025035 vs rs2010963： D’=0.505, r2=0.0214, P=***： This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that differ

关键词： vascular endothelial growth factor polymor-phism proliferative diabetic retinopathy non-proliferative diabetic retinopathy rs3025021 rs3025035 rs2010963

Identifying key elements in Knowledge-Cities benchmarking

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学术界 2010年第3期 241-248页

作者： Blanca C.garcia Northern Borderlands Research College

This paper presentation explores four key aspects of the Identity capital existing in emerging cities and *** aspects are part of capital systems approaches such as the Generic System of Capitals （GCS）:a tool to benchmark how cities are leveraging their capacity for knowledge-based *** this opportunity,elements of GSC’s Identity Capital have been emphasized to observe a combination of clarity and differentiation aspects of a city identity in four distinct *** context-based identity seemingly illustrates how knowledge cities in the edge are building their identity advantage in the knowledge-based international arena.

关键词： Generic Capitals System Identity Capital Benchmarking Borderland Knowledge Cities