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Robust H-Filtering for Lipschitz Nonlinear Systems via Multiobjective Optimization

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Journal of Signal and Information Processing 2010年第1期1卷 24-34页

作者： Masoud Abbaszadeh horacio J. Marquez 不详

In this paper, a new method of filtering for Lipschitz nonlinear systems is proposed in the form of an LMI optimization problem. The proposed filter has guaranteed decay rate (exponential convergence) and is robust against unknown exogenous disturbance. In addition, thanks to the linearity of the proposed LMIs in the admissible Lipschitz constant, it can be maximized via LMI optimization. This adds an extra important feature to the observer, robustness against nonlinear uncertainty. Explicit bound on the tolerable nonlinear uncertainty is derived. The new LMI formulation also allows optimizations over the disturbance attenuation level ( cost). Then, the admissible Lipschitz constant and the disturbance attenuation level of the filter are simultaneously optimized through LMI multiobjective optimization.

关键词： Lipschitz Nonlinear Systems Optimal Filters Nonlinear Filtering LMI Optimization

国立罗萨里奥大学汉语学习者语音习得情况研究

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国立罗萨里奥大学汉语学习者语音习得情况研究

作者： PARAMO horacio AGUSTIN 安徽大学

学位级别：硕士

本研究以国立罗萨里奥大学初级阶段15名汉语学习者为研究对象,针对他们学习汉语声母、韵母和声调偏误问题进行调查研究。以对比分析、难度等级模式、偏误分析理论为研究基础,运用对比分析法和调查法为研究方法,对西班牙母语者的汉语中... 详细信息

本研究以国立罗萨里奥大学初级阶段15名汉语学习者为研究对象,针对他们学习汉语声母、韵母和声调偏误问题进行调查研究。以对比分析、难度等级模式、偏误分析理论为研究基础,运用对比分析法和调查法为研究方法,对西班牙母语者的汉语中介语音进行描述分析。首先在描述西语和汉语声韵调差异基础上,了解学习者对于汉语语音的难点认知、听辨感知能力以及中介语语音的发展;继而通过语音测试,结合问卷调查的方法,考察分析了阿根廷汉语初学者在汉语学习过程中的偏误现象,并探讨这些偏误出现的原因;最后结合相关教学经验提出有针对性的教学策略,寻找出克服“石化”现象,以期达到提高汉语语音教学质量的目标。笔者在教学实践中与通过研究发现,西班牙母语者除了收到母语迁移影响以外,还受到许多其他因素影响,如学习动机、个体差异、交际策略、教材、教师等因素。这些因素影响到学习者声母偏误形象出现在送气和不送气音混淆、舌尖音和舌面音混淆、清音浊化,韵母偏误出现在鼻韵母复韵母的介音和韵尾问题、卷舌音不到位,声调偏误出现在二声和三声上。汉语语音习得虽然离不开学习者母语即西班牙语的影响,但通过后天学习方法和态度的改变,仍可以达到理想的训练预期。因此,除了课堂教授语音知识外,对于教材的编排、教师的课程设计,以及如何提高学习者语音的学习动机和信心,都是海外汉语语音教学应该继续努力的方向。研究结论可为二语教学项目的设计提供指导策略。

关键词：阿根廷中文学习者偏误分析对比分析汉语语音教学

Seasonal variation in native hydraulic conductivity between two deciduous oak species

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Journal of Plant Ecology 2020年第1期13卷 78-86页

作者： Dilia Mota-Gutiérrez Guadalupe Arreola-González Rafael Aguilar-Romero horacio Paz Jeannine Cavender-Bares Ken Oyama Antonio Gonzalez-Rodriguez Fernando Pineda-García Facultad de Biología Universidad Michoacana de San Nicolás de Hidalgo.Edificio RCiudad UniversitariaGral.Francisco J.Múgica S/N A-1Felicitas de Río58030 MoreliaMichoacánMexico Escuela Nacional de Estudios Superiores Unidad MoreliaUniversidad Nacional Autónoma de México.Antigua Carretera a Pátzcuaro 8701Ex-Hacienda de San Joséde La Huerta58190 MoreliaMichoacánMexico Instituto de Investigaciones en Ecosistemas y Sustentabilidad Campus MoreliaUniversidad Nacional Autónoma de México.Antigua Carretera a Pátzcuaro 8701Ex-Hacienda de San Joséde La Huerta58190 MoreliaMichoacánMexico Deparment of Ecology Evolution and BehaviorUniversity of MinnesotaSaint PaulMN 55108USA

Aims Mechanisms of plant drought resistance include both tolerance and *** vulnerability to embolism and turgor loss point are considered traits that confer tolerance,while leaf abscission and deciduousness characterizes the avoidance *** these mechanisms are thought to trade-off expressing a continuum among species,little is known on how variation in the timing and duration of leaf shedding in response to drought affect the relationship between xylem and leaf *** the present study,we explored the extent to which drought tolerance differs between two oak(Quercus)species that exhibit different leaf shedding ***,we predicted that *** Trel.,which loses leaves at the end of the dry season(late-deciduous)and is thus exposed to a greater risk of cavitation,would be more drought tolerant and more conservative in its water use than *** Liebm.,which loses its leaves for only a short period of time in the middle of the dry season(brevideciduous).Methods The study was conducted in central Mexico in a single population of each of the two oak species,separated from each other by a distance of 1.58 km,and by an altitudinal difference of 191 *** deserticola(late deciduous)is more frequent down slope,while ***(brevideciduous)tends to occur at higher elevations along the *** assessed seasonal differences(rainy versus dry season)in native stem hydraulic conductivity,and tested for variation in xylem vulnerability to cavitation,leaf water use and leaf turgor loss point between the two *** Findings The two oak species did not differ in traits conferring drought tolerance,including xylem vulnerability to embolism,leaf turgor loss point,or stomatal ***,both species had different performance during the dry season;the brevideciduous species had lower negative impact in the xylem function than the late-deciduous ***,seasonal changes in plant physiological performance

关键词： Quercus hydraulic conductivity embolisms leaf phenology

Kinematic Decoupled Core Paradigm: Counterrotation or Just Warping

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International Journal of Astronomy and Astrophysics 2016年第2期6卷 198-205页

作者： Rubén J. Díaz horacio Dottori ICATE CONICET San Juan Argentina Gemini Observatory La Serena Chile Instituto de Física UFRGS Porto Alegre Brazil

Several mechanisms have been proposed in recent years to explain kinematic decoupled cores (KDCs) in early type galaxies as well as the large differences in angular momentum between KDCs and host galaxy. Most of the proposed scenarios involve large fractions of merging events, high speed interactions with dwarf spheroidal galaxies, cusp effect of the dark matter density profiles, etc. We here argue that counterrotation as well as fast and slow rotation of disks or spheroids at the center of galaxies can also be explained by a misalignment of the central spheroid equatorial plane with regard to that defined by the observed external stellar rotation. Contrary to what happens at the outer region of disk galaxies, once instability has led to the inner warped core, the perturbed orbits can maintain a common orientation due to the rigid body like rotation at the central region of the galaxy. The spatial configuration that furnishes the smallest angular momentum difference between the KDC and the host galaxy is completely defined by observed parameters in the plane of the sky, namely, the inclination of the inner and outer disks and the angle between the two lines of nodes. As an example we modeled the paradigmatic and extreme case of the 2D radial velocity field of NGC 4382 nucleus. Tilt angles of the KDC not larger than 30 degrees also allow explaining fast and low rotators of the called “Sauron paradigm” in a unified scenario. The maximum for the three parameters, namely, velocity of the inner rotator, difference of position angle and difference with the outer rotation velocity of the whole Sauron sample, are consistently correlated in agreement with the proposed scenario. These quantities do not correlate with the galaxies magnitude, mass (since large and dwarf spheroidals show apparent counterrotation as well) or environment, also suggesting that an internal phenomenon like the central spheroid warping, that we are here proposing, may be at work.

关键词： Galaxies Disks Counterrotation Inner Warps Kinematics

Updated outcomes using clockwise technique for laparoscopic distal pancreatectomy:Optimal treatment of benign and malignant disease of the left pancreas

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Laparoscopic, Endoscopic and Robotic Surgery 2021年第1期4卷 9-13页

作者： Jordan S.Dutcher Domenech Asbun Mary P.Tice horacio J.Asbun John A.Stauffer Mayo Clinic Alix School of Medicine JacksonvilleFLUSA Department of General Surgery Mayo Clinic FloridaJacksonvilleFLUSA Hepatobiliary and Pancreas Surgery Miami Cancer InstituteMiamiFLUSA

Background:Laparoscopic distal pancreatectomy(LDP)has become the preferred approach for surgical management of left sided pancreas *** institution previously published its experience with distal pancreatectomies using a clockwise technique with good *** now reexamine our outcomes across a longer time ***:From August 2008 to November 2020,364 patients underwent LDP by hepatobiliary surgeons(HA and JS).All procedures were performed using the same clockwise approach,which includes the stepwise slow compression *** descriptive analysis of patient demographic,clinical,operative,and pathologic data was ***:Of the 364 patients who underwent LDP using this technique,clinically significant postoperative pancreatic fistula(POPF)was noted in 26(7.1%)patients,while major morbidity and mortality were reported in 9.9%and 0.3%,***-assisted method was required for 18(4.9%)patients and unplanned conversion in 20(5.5%)*** a subset analysis of patients with pancreatic adenocarcinoma(n¼90),POPF was noted in 13(14.4%),with minor complications occurring in 34.4%and major morbidity in 14.4%.Conclusion:LDP with a clockwise approach for dissection,combined with the stepwise slow compression technique results in excellent outcomes,with even lower POPF rates than originally *** analysis of patients with pancreatic adenocarcinoma shows acceptable perioperative outcomes with this technique.

关键词： Laparoscopic distal pancreatectomy Pancreatic ductal adenocarcinoma Outcomes

Study of copper-cysteamine based X-ray induced photodynamic therapy and its effects on cancer cell proliferation and migration in a clinical mimic setting

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Bioactive Materials 2022年第1期7卷 504-514页

作者： Xiangyu Chen Jiayi Liu Ya Li Nil Kanatha Pandey Taili Chen Lingyun Wang Eric horacio Amador Weijun Chen Feiyue Liu Enhua Xiao Wei Chen Department of Radiology The Second Xiangya Hospital of Central South UniversityChangshaHunanChina Department of Physics The University of Texas at ArlingtonArlingtonTX76019USA Department of Oncology Xiangya HospitalCentral South UniversityChangshaHunan Province410011China Department of Oncology The Second Xiangya Hospital of Central South UniversityChangshaHunanChina

Copper-cysteamine as a new generation of sensitizers can be activated by light,X-rays,microwaves,or ultrasound to produce reactive oxygen species.X-ray induced photodynamic therapy(X-PDT)has been studied extensively;however,most of the studies reported so far were conducted in the laboratory,which is not conducive to the clinical translation *** this contribution,for the first time,we investigated the treatment efficiency of copper-cysteamine(Cu-Cy)based X-PDT by mimicking the clinical conditions with a clinical linear accelerator and building deep-seated tumor models to study not only the effectiveness but also its effects on the cell migration and proliferation in the level of the cell,tissue,and *** results showed that,without X-ray irradiation,Cu-Cy nanoparticles(NPs)had a low toxicity in HepG2,SK-HEP-1,Li-7,and 4T1 cells at a concentration below 100 mg/***,for the first time,it was observed that Cu-Cy mediated X-PDT can inhibit the proliferation and migration of these cell lines in a dose-dependent *** markers of migration and cell proliferation,proliferating cell nuclear antigen(PCNA)and E-cadherin,from tumor tissue in the X-PDT group were remarkably different from that of the control ***,the MRI assessment showed that the Cu-Cy based X-PDT inhibited the growth of deeply located tumors in mice and rabbits(p<0.05)without any obvious toxicities in ***,these new findings demonstrate that Cu-Cy NPs have a safe and promising clinical application prospect in X-PDT to improve the efficiency of radiotherapy(RT)for deep-seated tumors and effectively inhibit tumor cell proliferation and migration.

关键词： Copper-cysteamine Nanoparticle Photodynamic therapy X-ray Cell migration Proliferation

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中国，一个哥伦比亚水果的新兴市场

中国，一个哥伦比亚水果的新兴市场

作者： Cruz horacio Andres（何睿修）华东理工大学

学位级别：硕士

本文旨在研究和分析一种全新的可行性,即中国能否作为一个新的崭新的市场来销售哥伦比亚的热带水果。从中哥两国的生产、市场、后勤以及其他方面来看,尤其是南美国家的产品都有可能在中国扎根。比如,后勤方面就不成问题,比如哥伦比亚的... 详细信息

本文旨在研究和分析一种全新的可行性,即中国能否作为一个新的崭新的市场来销售哥伦比亚的热带水果。从中哥两国的生产、市场、后勤以及其他方面来看,尤其是南美国家的产品都有可能在中国扎根。比如,后勤方面就不成问题,比如哥伦比亚的邻国——秘鲁和智利都有充足的的储备并向中国出口水果。哥伦比亚是一个新兴的发展中国家,紧跟其他发达国家的脚步。该国农业在总GDP中所占的比重呈下降趋势以此支持工业和服务业的发展,但是维持一定的农业增长率也是相当重要的,这样也能为哥伦比亚的经济发展作出了贡献。从历史上来看,哥伦比亚过去一直是一个以纯粹的农耕国家。随着近年来世界形势的不断变化,哥伦比亚加强了对制造业的发展,以及对如原油、铁、矿等自然资源进行开发,尽管如此,哥伦比亚还是保留了大量的劳动力(直接或间接)和土地用来发展农业。将农业对于哥伦比亚的重要性举例,作为世界最大的热带水果供应地,每年哥伦比亚向包括美国、荷兰、瑞典、法国等国家出口水果。在2007年,许多发达国家遭遇经济危机之时,因为缺乏资金和出于保护国内果农及生产商,决定减少从哥伦比亚进口水果,但此时中国却异军突起。当时中国已经成为世界上重要的经济体,是世界上最大的贸易伙伴,任何国家都因为中国的出色表现,想与中国进行洽谈合作。此外,一方面中国在国际贸易充满活力,另一方面,哥伦比亚希望能够结交多样化的伙伴,以此来摆脱对美、荷、瑞、法等国的依赖,所以哥方认准了中国这个潜在的市场。还有,从数据上来看,中国拥有泱泱13.5亿的人口,而且人们还喜欢热带水果的口味。所以这篇论文旨在讨论将哥伦比亚水果引进中国是否可行,哪些水果适合上海人民的口味,分析哥伦比亚的潜在竞争对手,以及水果的运输,市场和分销等问题。

关键词：哥伦比亚热带水果中国进口市场

Investigation on the Fire Resistance of Cellular Steel Beam with Sinusoidal Openings

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Open Journal of Civil Engineering 2023年第4期13卷 637-663页

作者： Michee Sagali Mutentu Bikoumou Gambat Maximino horacio Yinghua Yang School of Civil Engineering Xi’an University of Architecture and Technology Xi’an China School of Civil Engineering Chang’an University Xi’an China

This paper investigated the fire resistance of CSBs with various parameters under high temperature rise due to fire using finite element software ABAQUS. The mechanical parameters of CSBs are analyzed, including load-bearing capacity and the temperature distribution during the heating process. Through structural analysis simulation of the entire heating process, the structural response of the CSBs is divided into five stages: elastic stage, elastic-plastic stage, self-balancing stage, catenary stage and ultimate destruction stage. The results indicate that the opening diameter-to-height ratio, opening spacing-to-height ratio and load ratio significantly affect the structural responses of CSBs in fire, followed by opening shape as secondary effects. In all the numerical analyzes, CSBs are analyzed with a uniformly distributed load and having simply supported boundary conditions.

关键词： Fire Resistance Thermal and Structural Analysis Cellular Steel Beam Transient Temperature Effect

A new method for quantification of total polyphenol content in medicinal plants based on the reduction of Fe(III)/1,10-phenanthroline complexes

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Advances in Biological Chemistry 2013年第6期3卷 525-535页

作者： Monica Gabriela do Santo Cecilia Veronica Nunez horacio Dorigan Moya Faculdade de Medicina da Fundacao do ABC CEPES(Centro de EstudosPesquisaPrevencao e Tratamento em Saúde)Santo AndréBrazil Laboratório de Bioprospeccao e Biotecnologia COTI(Coordenacao de Tecnologia e Inovacao)INPA(Instituto Nacional de Pesquisas da Amazonia)ManausBrazil

This paper proposes an alternative analytical spectrophotometric method for the total polyphenol quantification in the aqueous extract of plants. When these extracts are added to solutions of Fe(III), in presence of 1,10-phenanthroline, the absorbance values at 551 nm (A511nm) due to the complexes formed are proportional to the total polyphenol concentration expressed as pyrogallic acid (PA). A typical calibration graph of A511nm values vs. PA is linear from 0.16 to 0.64 mg L-1 (r = 0.994, n = 6) with a limit of detection 0.041 mg L-1. The results of the polyphenol content of the aqueous extracts of twenty medicinal Brazilian plants obtained with the proposed method were compared with values using the Folin-Ciocalteu reagent. A paired t-test revealed no statistically significant difference for the species analyzed. The total antioxidant capacity of the same twenty extracts was determined based on the scavenging of stable radical DPPH.

关键词： Polyphenols Medicinal Brazilian Plants 1,10-Phenanthroline Iron(III) Antioxidant Activity