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Study of genetic algorithms as a global optimization technique for full-waveform inversion

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Study of genetic algorithms as a global optimization techniq...

Foraging Behavior,Direct Interference and Habitat Use in Three Species of Flamingos(Phoenicopterus Chilensis,Phoenicoparrus Andinus and Phoenicoparrus Jamesi) in Mar Chiquita Lagoon,Córdoba,Argentina

2020年中国地球科学联合学术年会

作者： Carlos honorio Bastidas Perez Yang Liu China University of Petroleum-Beijing China University of Petroleum-Beijing Karamay Campus

1. Introduction Full-waveform Inversion(FWI) is generally implemented with gradient-based techniques due to the computational cost of wave-equation modeling. However, gradient-based optimization techniques are very likely to get trapped in local minima when error exceeds half a period caused by an inaccurate starting model(i.e. cycle skipping).

关键词： FWI Study of genetic algorithms as a global optimization technique for full-waveform inversion

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 63-64页

作者： Lucila CASTRO Ricardo torres Department of Biodiversity and Ecology.National University of Cordoba

The Laguna Mar Chiquita,located northeast of the province of Córdoba in Argentina,is the only non-Andean place where three flamingo species regularly coexist in the southern part of South *** of these species,

关键词： Phoenicoparrus andinus Phoenicoparrus jamesi Phoenicopterus chilensis Mar Chiquita interactions foraging depth selectivity.

Spatiotemporal patterns of burned areas,fire drivers,and fire probability across the equatorial Andes

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Journal of Mountain Science 2021年第4期18卷 952-972页

作者： Xavier ZAPATA-RiOS Carmen LOPEZ-FABARA Abigail NAVARRETE Sandra torres-PAGUAY Miguel FLORES Department of Civil and Environmental Engineering Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Center for Research and Water Resources Studies(CIERHI) Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Faculty of Agricultural Sciences Universidad Central del EcuadorAv.UniversitariaP.O.Box 17-03-100QuitoEcuador Modeling Optimization and Inferential Statistics Group(MODES)Department of MathematicsEscuela Politecnica NacionalLadron de Guevara Ell-253P.O.Box 17-01-2759QuitoEcuador

Field-based fire studies in the equatorial Andes indicate that fires are strongly associated with biophysical and anthropogenic ***,fire controls and fire regimes at the regional scale remain ***,this paper describes spatial and temporal burned-area patterns,identifies biophysical and anthropogenic fire drivers,and quantifies fire probability across 6°of latitude and 3°of longitude in the equatorial *** spatial and temporal burned-area analysis was carried out based on 18 years(2001-2018)of the MCD64 A1 MODIS burned-area ***,topography,vegetation,and anthropogenic variables were integrated in a logistic regression model to identify the significance of explanatory variables and determine fire occurrence probability.A total of 5779 fire events were registered during the 18 years of this study,located primarily along the western cordillera of the Andes and spreading from North to ***-eight percent of these fires took place within two fire hotspots located in the northwestern and southwestern corners of the study ***-nine percent occurred during the second part of the year,between June and *** largest density of fires was primarily located on herbaceous vegetation and *** show that mean monthly temperature,precipitation and NDVI during the prefire season,the location of land cover classes such as forest and agriculture,distance to roads and urban areas,slope,and aspect were the most important determinants of spatial and temporal fire *** logistic regression model achieved a good accuracy in predicting fire probability(80%).Probability was higher in the southwestern and northern corners of the study area,and lower towards the north in the western and eastern piedmonts of the *** analysis contributes to the understanding of fires in mountains within the *** results here presented have the potential to contribute to fire management and control in the regi

关键词： MODIS MCD64A1 Spectral vegetation indices Pre-fire season NDVI and precipitation Remote sensing

Fast preparation route to high-performances textured Sr-doped Ca_3Co_4O_9 thermoelectric materials through precursor powder modification

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Science China Materials 2019年第3期62卷 399-406页

作者： Miguel Angel torres Gustavo Garcia Idoia Urrutibeascoa Maria Antonieta Madre Juan Carlos Diez Andres Sotelo ICMA (CSIC-Universidad de Zaragoza) Centro Stirling S. Coop. Mondragon Unibertsitatea

This work presents a short and very efficient method to produce high performance textured Ca_3Co_4O_9 thermoelectric materials through initial powders modification. Microstructure has shown good grain orientation, and low porosity while slightly lower grain sizes were obtained in samples prepared from attrition milled powders. All samples show the high density of around 96% of the theoretical *** similar characteristics are reflected in, approximately,the same electrical resistivity and Seebeck coefficient values for both types of samples. However, in spite of similar power factor(PF) at low temperatures, it is slightly higher at high temperature for the attrition milled samples. On the other hand, the processing time reduction(from 38 to 2 h) when using attrition milled precursors, leads to lower mechanical properties in these samples. All these data clearly point out to the similar characteristics of both kinds of samples, with a drastic processing time decrease when using attrition milled precursors, which is of the main economic importance when considering their industrial production.

关键词： ceramics oxides hot-pressing electrical properties power factor

Frequency Response Optimization of Dual Depletion InGaAs/InP PIN Photodiodes

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Photonic Sensors 2016年第1期6卷 63-70页

作者： J. M. torres PEREIRA Joao Paulo N. torres Instituto de Telecomunicacoes Instituto Superior Tecnico-Universidade de Lisboa Lisboa Portugal

The frequency response of a dual depletion p-i-n （PIN） photodiode structure is investigated. It is assumed that the light is incident on the N side and the drift region is located between the N contact and the absorption region. The numerical model takes into account the transit time and the capacitive effects and is applied to photodiodes with non-uniform illumination and linear electric field profile. With an adequate choice of the device＇s structural parameters, dual depletion photodiodes can have larger bandwidths than the conventional PIN devices.

关键词： PIN photodiodes dual depletion frequency response modeling

滞留在工厂中的人：王兵、贾樟柯纪录片中的社会场面调度

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滞留在工厂中的人：王兵、贾樟柯纪录片中的社会场面调度

作者： honorio de Paula Rocha Filho 重庆大学

学位级别：硕士

贝雷斯·雷诺德(Bérénice Reynaud)在研究中国纪录片的一文中指出,随着小型高清数码摄影机和非线性编辑技术的普及,在中国的纪录电影创作中,拍摄者可以独立地、方便的寻求拍摄素材。这带来一种真实电影拍摄手法,可以让中国社会的深层... 详细信息

贝雷斯·雷诺德(Bérénice Reynaud)在研究中国纪录片的一文中指出,随着小型高清数码摄影机和非线性编辑技术的普及,在中国的纪录电影创作中,拍摄者可以独立地、方便的寻求拍摄素材。这带来一种真实电影拍摄手法,可以让中国社会的深层转变直截了当地被捕捉。在这些新技术的帮助下,直接电影得以再设计并与中国社会现实相结合。摄像机为拍摄者与素材的邂逅起到了穿针引线的作用,而结构与主体的碰撞则构成了近距离型纪录片的内容。斯泰拉·布鲁兹(Stella Bruzzi)在《新纪录片——批判性导论》一书中,指出了一个关键性的问题,即到底是哪一部分力量主导了素材(真实性)与摄像机或导演之间的关系;她指出纪录片在传统上被视为由错综复杂的客观真实性与主观性构成的产物。从以上观点出发,我尝试解释真实性与影像之间的关系——本文着重讨论两部电影:贾樟柯的"二十四城记"(2008)和王兵的“铁西区”(2002)——电影中展示了在中国经济转型过程中,工厂中的工人的生活变迁状况。在贾樟柯的《二十四城记》中,三条主线相互交织,即以第一人称角度所做的采访,虚实结合的表演,以及实地场景——以此来讲述一个口头流传的故事:在成都某地,因为要新建一座大型的购物中心,该地一家工厂不得不搬迁。在王兵的《铁西区》中,作者用一个复杂的长镜头表现出计划经济体制的工厂处于新旧交替改革前夜的场景。更重要的是,工厂里工人的生活和家庭也面临挑战。紧贴真实电影这条主线,王兵坚持用镜头来记录工人们在过渡时期的真实生活。在王兵的这部电影中,什么是社会编码的原始题材呢?这是对摄像机存在的自然反应吗?究竟揭示了这些工人们日常生活中的哪些真实的场景?而另一方面,在贾樟柯的电影中,他在探讨真实与戏剧的关系时,用什么来体现社会的场面调度?在分镜头中引入外在物、在同一空间下用多种方式来表现的做法,既是一种叙事手法也是一种语境的体现。

关键词：全球化直接电影社会场面调度王兵《铁西区》、贾樟柯《二十四城记》

Algorithms for Computing Some Invariants for Discrete Knots

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Applied Mathematics 2013年第11期4卷 1526-1530页

作者： Gabriela Hinojosa David torres Rogelio Valdez Facultad de Ciencias Universidad Autónoma del Estado de Morelos Cuernavaca México

Given a cubic knot K, there exists a projection? of the Euclidean space R3?onto a suitable plane ?such that p(K) is a knot diagram and it can be described in a discrete way as a cycle permutation. Using this fact, we develop an algorithm for computing some invariants for K: its fundamental group, the genus of its Seifert surface and its Jones polynomial.

关键词： Cubic Knots Discrete Knots Algorithms

Dynamically generated N* resonances from the interaction of two mesons and a baryon

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Chinese Physics C 2009年第12期33卷 1302-1306页

作者： A. Martínez torres K. P. Khemchandani E. Oset Departamento de Física Teórica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain Centro de Física Teórica Departamento de Física Universidade de Coimbra P-3004-516 Coimbra Portugal

We have studied the ππN system and coupled channels by using of the Faddeev equations and two N* and one △ states, all of them with JP =1/2+, have been found in the formalism as dynamically generated states. In addition, signatures for a new N* resonance with JP =1/2+ are found around an energy of 1920 MeV in the three-body center of mass system.

关键词： Few-body systems chiral dynamics S = 0 resonances

A Data Mining Approach to Detecting Bias and Favoritism in Public Procurement

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Intelligent Automation & Soft Computing 2023年第6期36卷 3501-3516页

作者： Yeferson torres-Berru Vivian F.Lopez-Batista Lorena Conde Zhingre University of Salamanca Salamanca37008Spain Instituto Tecnológico Superior Sudamericano Loja1101608Ecuador Universidad Internacional del Ecuador Loja1101608Ecuador

In a public procurement process,corruption can occur at each stage,favoring a participant with a previous agreement,which can result in over-pricing and purchases of substandard products,as well as gender *** paper’s aim is to detect biased purchases using a Spanish Language corpus,ana-lyzing text from the questions and answers registry platform by applicants in a public procurement process in ***,gender bias is detected,pro-moting both men and women to participate under the same *** order to detect gender bias and favoritism towards certain providers by contracting enti-ties,the study proposes a unique hybrid model that combines Artificial Intelli-gence algorithms and Natural Language Processing(NLP).In the experimental work,303,076 public procurement processes have been analyzed over 10 years(since 2010)with 1,009,739 questions and answers to suppliers and public insti-tutions in each *** bias and favoritism were analyzed using a Word2-vec model with word embedding,as well as sentiment analysis of the questions and answers using the VADER *** 32%of cases(96,984 answers),there was favoritism or gender bias as evidenced by responses from contracting *** proposed model provides accuracy rates of 88% for detecting favor-itism,and 90%for detecting gender *** one-third of the procure-ment processes carried out by the state have indications of corruption and *** Latin America,government corruption is one of the most significant challenges,making the resulting classifier useful for detecting bias and favoritism in public procurement processes.

关键词： Favoritism bias natural language processing Word2vec sentiment analysis word embeddings