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optimization for performance-based design under seismic demands, including social costs

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 315-328页

作者： oscar Moller Ricardo o.Foschi Juan P.Ascheri Marcelo Rubinstein Sergio Grossman Instituto de Mecanica Aplicada y Estructuras (IMAE) Facultad Cs.Ex. Ingenieríay Agrimensura Universidad Nacional de Rosario Riobambay Berutti 2000 Rosario Argentina Civil Engineering Department University of British Columbia 6250 Applied Sciences Lane Vancouver B.C. Canada V6T1Z4

Performance-based design in earthquake engineering is a structural optimization problem that has, as the objective, the determination of design parameters for the minimization of total costs, while at the same time satisfying minimum reliability levels for the specifi ed performance criteria. Total costs include those for construction and structural damage repairs, those associated with non-structural components and the social costs of economic losses, injuries and fatalities. This paper presents a general framework to approach this problem, using a numerical optimization strategy and incorporating the use of neural networks for the evaluation of dynamic responses and the reliability levels achieved for a given set of design parameters. The strategy is applied to an example of a three-story offi ce building. The results show the importance of considering the social costs, and the optimum failure probabilities when minimum reliability constraints are not taken into account.

关键词： earthquake engineering performance-based design optimization reliabiliy social costs

Levi and Malcev Theorems for Finite-Dimensional Algebras from the Variety Defined by the Identities x^(2)=J(x,y,zu)=0

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Algebra Colloquium 2021年第1期28卷 87-90页

作者： oscar Guajardo Garza Marina Rasskazova Liudmila Sabinina Centro de Investigacion en Ciencias UAEMCuernavacaMexico omsk State Technical University pr.Mira 11OmskRussia

We study the variety of binary Lie algebras defined by the identities x^(2)=J(x,y,zu)=0,where J(a,b,c)denotes the Jacobian of a,b,*** on previous work by Carrillo,Rasskazova,Sabinina and Grishkov,in the present articl... 详细信息

关键词： Malcev theorem Levi factor splitting algebra binary Lie algebra

Integrated site-specific quantification of faecal bacteria and detection of DNA markers in faecal contamination source tracking as a microbial risk tracking tool in urban Lake ecosystems

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Journal of oceanology and Limnology 2018年第5期36卷 1629-1642页

作者： oscar omondi DoNDE TIAN Cuicui XIAo Bangding Key Laboratory of Algal Biology of Chinese Academy of Sciences-Lake Restoration Research Group Institute of Hydrobiology Chinese Academy of SciencesWuhan 430072China International College University of Chinese Academy of SciencesBeijing 100049China Egerton University Department of Environmental ScienceP.O.Box 536-20115Egerton-Kenya

The presence of feacal-derived pathogens in water is responsible for several infectious diseases and deaths worldwide. As a solution, sources of fecal pollution in waters must be accurately assessed, properly determined and strictly controlled. However, the exercise has remained challenging due to the existing overlapping characteristics by different members of faecal coliform bacteria and the inadequacy of information pertaining to the contribution of seasonality and weather condition on tracking the possible sources of pollution. There are continued ef forts to improve the Faecal Contamination Source Tracking(FCST) techniques such as Microbial Source Tracking(MST). This study aimed to make contribution to MST by evaluating the efficacy of combining site specific quantification of faecal contamination indicator bacteria and detection of DNA markers while accounting for seasonality and weather conditions' eff ects in tracking the major sources of faecal contamination in a freshwater system(Donghu Lake, China). The results showed that the use of cyd gene in addition to lacZ and uidA genes differentiates E. coli from other closely related faecal bacteria. The use of selective media increases the pollution source tracking accuracy. BSA addition boosts PCR detection and increases FCST efficiency. Seasonality and weather variability also influence the detection limit for DNA markers.

关键词： assay contamination faecal bacteria indicator source tracking water quality

Detecting polygenic selection in marine populations by combining population genomics and quantitative genetics approaches

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Current Zoology 2016年第6期62卷 603-616页

作者： Pierre-Alexandre GAGNAIRE oscar E. GAGGIoTTI Universite Montpellier 2 Place Eugene Bataillon 34095 Montpellier Cedex 5 France ISEM - CNRS UMR 5554 SMEL 2 rue des Chantiers Sete 34200 France Scottish oceans Institute University of St Andrews East Sands St Andrews KY16 9LB UK

Highly fecund marine species with dispersive life-history stages often display large population sizes and wide geographic distribution ranges. Consequently, they are expected to experience reduced genetic drift, efficient selection fueled by frequent adaptive mutations, and high migration loads. This has important consequences for understanding how local adaptation proceeds in the sea. A key issue in this regard, relates to the genetic architecture underlying fitness traits. Theory predicts that adaptation may involve many genes but with a high variance in effect size. Therefore, the effect of selection on allele frequencies may be substantial for the largest effect size loci, but insignificant for small effect genes. In such a context, the performance of population genomic methods to unravel the genetic basis of adaptation depends on the fraction of adaptive genetic variance explained by the cumulative effect of outlier loci. Here, we address some methodological challenges associated with the detection of local adaptation using molecular approaches. We provide an overview of genome scan methods to detect selection, including those assuming complex demographic models that better describe spatial population structure. We then focus on quantitative genetics approaches that search for genotype-phenotype associations at different genomic scales, including genome-wide methods evaluating the cumulative effect of variants. We argue that the limited power of single locus tests can be alleviated by the use of polygenic scores to estimate the joint contribution of candidate variants to phenotypic variation.

关键词： local adaptation genome scans quantitative genetics genotype-phenotype association polygenic scores.

Characteristics of developing scour-holes at a sand-embedded cylinder

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International Journal of Sediment Research 2008年第3期23卷 258-266页

作者： oscar LINK Florian PFLEGER Ulrich ZANKE Dept. of Civil Engineering University of Concepción Edmundo Larenas 270 Concepción Chile.Dr.-Ing. Assistant Prof. Doctoral Research Fellow Institute for Hydromechanics Technische Universitt München Arcisstrasse 21 80333 München Germany. Institute for Hydraulic and Water Resources Engineering Darmstadt University of Technology Rundeturmstraβe 1 64283 Germany.Full Prof.

Characteristics of developing scour-holes at a sand-embedded 0.2 m diameter circular cylinder are presented. Non-intrusive, high-resolution topographic measurements of developing scour-holes were made with an experimental installation using a laser distance sensor (LDS) and precision step-motors. A clear-water experiment was conducted with bed shear stress equal to 95% of the critical bed shear stress for the initiation of sediment motion at the undisturbed plane sand bed with a d50 of 0.26 mm. During the running experiment of 21 hours duration, measurements were taken by the LDS in different azimuthal half-planes with θ = 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165 and 180o in order to study the spatio-temporal variation of geometric properties in developing scour-holes. After 21 hours, the equilibrium condition was approached, with a scour rate less than d50 per hour. Measurement of maximum scour depth in different azimuthal half-planes at different points in time during the experiment show that scour started at the cylinder side and surrounded the cylinder after about 20% of experiment time. Slopes of developing scour-holes presented three regions with different inclinations, which were attributed to vortex action. Both maximum scour depth and maximum scour radius at different azimuthal half-planes are well correlated with the maximum scour depth at plane with θ = 0o. When providing maximum scour depth at the cylinder front, the presented correlations are useful for simple calculation of scour-hole topography. This work provides an experimental database for advanced numerical simulation for loose sediment hydraulics.

关键词： Scour Bridges Piers Sediment transport Loose sediment hydraulics

A Robust MPP Tracker Based on Sliding Mode Control for a Photovoltaic Based Pumping System

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International Journal of Automation and computing 2017年第4期14卷 489-500页

作者： Farhat Maissa oscar Barambones Sbita Lassad Aymen Fleh Department of Electrical Electronics and Communications Engineering American University of Ras A1 Khaimah Ras AI Khaimah 10021 UAE Advanced Control Group Faculty of Engineering of Vitoria-Gasteiz University of the Basque Country Bilbao Spain Electrical and Automatic Engineering Department Engineering School of Gabes University of Gabes Zrig Gabes 6029 Tunisia

In this paper, a mathematical model of the photovoltaic （PV） pumping system＇s main components is firstly established. Then, the design of maximum power point tracking （MPPT） stage that ensures battery charging is described. This work is motivated by the need of photovoltaic generator （PVG） that efficiently extracts maximum power. The PVG is a special source of energy which has nonlinear current-voltage characteristics depending on variations in temperature and solar irradiance. In order to achieve the MPPT operating goals, a special interest is focused on the variable structure sliding mode （SM） control strategy and the classic perturb and observe （P＆o） algorithm. The permanent magnet synchronous motor （PMSM） is selected as a pump driver. The field oriented control is performed as the motor drive strategy. Simulation results show a high level of efficiency, obtained with the proposed PV based pumping system. The performance comparison between SM controller and P＆o controller has been carried out to demonstrate the effectiveness of the former in drawing more energy and a fast response against irradiation disturbances.

关键词： Photovoltaic (PV) pump storage battery boost sliding mode control (SMC) maximum power point tracking (MPPT).

Hydrogen storage in a rare-earth perovskite-type oxide La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)o_3 for battery applications

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Rare Metals 2018年第12期37卷 1003-1013页

作者： John Henao oscar Sotelo Maura Casales-Diaz Lorenzo Martinez-Gomez CoNACYT-CIATEQ A.C. Av. Manantiales 23-AParque Industrial Bernardo Quintana Instituto de Ciencias Fisicas (ICF) Universidad Nacional Autonoma de Mexico (UNAM)-Campus Morelos

Recently, rare-earth perovskite-type oxides with the general formula ABo(A rare earth element, B transition metal, o oxygen) are regarded as promising materials for Ni/oxide batteries due to their hydrogen storage ability. In the present study, the hydrogen storage properties of the rare-earth perovskite-type oxide LaSrCoFeowere evaluated in alkaline solution and at various temperatures. The hydrogen storage properties were investigated electrochemically by applying galvanostatic charge/discharge currents. Electrochemical pressurecomposition-temperature isotherms were constructed using the Nernst equation. The exchange current density and proton hydrogen diffusion coefficient were calculated using linear polarization measurements and the potential-step method, respectively. Interestingly, the maximum hydrogen absorption capacity, re-calculated from the electrochemical capacity, is 1.72 wt% at 333 K and 6 mol·LKoH. In addition, the hysteresis value, calculated from pressure-composition-temperature isotherms, was429 J·molat 333 K,while the self-discharge rate was about 25% after 24-h storage at open circuit and at 333 K.

关键词： Hydrogen storage Rare earths Perovskites Ni/oxide batteries

An Architecture for Software Engineering Gamification

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Tsinghua Science and Technology 2020年第6期25卷 776-797页

作者： oscar Pedreira Felix Garcia Mario Piattini Alejandro Cortinas Ana Cerdeira-Pena the Universidade da Coruna Centro de Investigacion CITICLaboratorio de Bases de DatosFacultade de InformaticaElvinaA Coruna15071Spain the Universidad de Castilla-La Mancha Grupo AlarcosEscuela Superior de InformaticaPaseo de la Universidad4Ciudad Real13071Spain.

Gamification has been applied in software engineering to improve quality and results by increasing people’s motivation and engagement.A systematic mapping has identified research gaps in the field,one of them being the difficulty of creating an integrated gamified environment comprising all the tools of an organization,since most existing gamified tools are custom developments or *** this paper,we propose a gamification software architecture that allows us to transform the work environment of a software organization into an integrated gamified environment,i.e.,the organization can maintain its tools,and the rewards obtained by the users for their actions in different tools will mount *** developed a gamification engine based on our proposal,and we carried out a case study in which we applied it in a real software development *** case study shows that the gamification engine has allowed the company to create a gamified workplace by integrating custom-developed tools and off-the-shelf tools such as Redmine,TestLink,or JUnit,with the gamification *** main advantages can be highlighted:(i)our solution allows the organization to maintain its current tools,and(ii)the rewards for actions in any tool accumulate in a centralized gamified environment.

关键词： gamification software engineering gamification architecture gamification engine

Protein Shuttle between Nucleus and Cytoplasm:New Paradigms in the ABI5-dependent ABA Responses

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Molecular Plant 2019年第11期12卷 1425-1427页

作者： Inmaculada Sanchez-Vicente Pablo Albertos oscar Lorenzo Dpto.de Botanica y Fisiologia Vegetal Instituto Hispano-Luso de Investigaciones Agrarias(CIALE)Facultad de BiologiaUniversidad de SalamancaC/Rio Duero 1237185 SalamancaSpain Present address:Biotechnology in Horticultural Crops TU Munchen-WeihenstephanLiesel-Beckmann-Strasse 185354 FreisingGermany

Plant survival depends on seed germination,progression through post-germinative developmental checkpoints,and adaptation to abiotic *** these processes underlie a tightly controlled regulation by the stress hormone abscisic acid(ABA)at different levels,even though the main research focuses on changes in transcript and protein ***,protein fate undergoes complex readjustments that allow signal transduction to be integrated into physiological *** them,protein redox status,stability,capacity of oligomerization,formation of complexes,and subcellular compartmentalization become key points for plant reprogramming against stresses to acquire an optimal *** this Spotlight,we highlight and discuss the latest advances in dissecting the mechanisms driving protein dynamics of nucleocytoplasmic trafficking in the cell and its relevance for regulating the stability of ABI5 and the ABI5-dependent AB A signaling pathway(Figure 1).

关键词： Figure driving programming