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数学进展 2024年第2期53卷 303-309页

作者：祁瑾云郭振宇西北大学数论及其应用研究中心陕西西安710127 西安交通大学数学与统计学院陕西西安710049

广义Piatetski-Shapiro序列是形如([αn^(c)+β])的序列,其中c>1且c■N.本文研究了广义Piatetski-Shapiro序列中square-full数的分布.

关键词： square-full数 Piatetski-Shapiro序列指数和

Generation of a New coupled Ultra-Short Pulse System from a Group Theoretical Viewpoint: the cartan Ehresman connection

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chinese Physics Letters 2012年第2期29卷 5-8页

作者： Saliou Youssoufa victor K.Kuetche Timoleon c.Kofane National Advanced School of Engineering University of Yaounde IP.O.Box 8390Cameroon department of Physics Faculty of ScienceUniversity of Yaounde IP.O.Box 812Cameroon

Based upon the group theoretical jet bundle formalism introduced by Wahlquist and Estabrook for discussing the complete integrability of soliton systems,we investigate the prolongation structure of Wadati-Konno-Ichikawa isospectral evolution *** a result,we unearth a new physical coupled system entailing a hidden structural symmetry SL(3,R) arising in the description of ultra-short pulse propagation in optical nonlinear *** a matter of fact,we depict a graphical representation of one-breather and two-breather ultra-short pulses in motion with a non-zero angular *** extending the previous study to multidimensional symmetry SL(n,R),we unearth a more general class of multicomponent coupled nonlinear ultra-short pulse system with its associated inverse scattering formulation particularly useful in soliton theory.

关键词： theory soliton symmetry

L'expdition de chine Au capitaine Butler

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法语国家与地区研究 2003年第3期 2-5页

作者： victor hugo ,罗嘉美

此文是法国文豪雨果 186 1年 11月 2 5日回答参与火烧圆明园的英国军官巴特勒上尉的一封信。文章无情鞭笞了英法联军的野蛮行径 ,也展现了雨果作为一个伟大的人道主义作家的宽广胸怀和他对一个遥远的东方古国的深厚情愫。今年适值法国... 详细信息

此文是法国文豪雨果 186 1年 11月 2 5日回答参与火烧圆明园的英国军官巴特勒上尉的一封信。文章无情鞭笞了英法联军的野蛮行径 ,也展现了雨果作为一个伟大的人道主义作家的宽广胸怀和他对一个遥远的东方古国的深厚情愫。今年适值法国的中国文化年 ,谨以此文纪念这一友好盛事。

关键词： L’exp dition de chine Au capitaine Butler 雨果

“What is a Sociologist Doing Here?”An Unconventional People-centered Approach to Improve Warning Implementation in the Sendai Framework for Disaster Risk Reduction

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International Journal of Disaster Risk Science 2020年第2期11卷 218-229页

作者： victor Marchezini cemaden–National Early Warning and Monitoring center of Natural Disasters Distrito de Eug8nio de Melo 12.247-016Sao Jose dos CamposSPBrazil Doctorate Program on Earth System Science National Institute for Space ResearchSao Jose dos CamposBrazil Programa de Pós-Gradua??o em desastres Naturais ICT/Unesp-CemadenSao Jose dos Campos.Brazil

The Sendai Framework for Disaster Risk Reduction 2015–2030 recommends several actions for early warning systems(EWSs). However, there is a lack of information about their means of implementation. This article used institutional ethnography to analyze the 2012–2018 implementation of a national warning system in Brazil. The challenges related to daily activities, and the interdisciplinary works in the four axes of EWSs towards multi-hazard and people-centered approaches are discussed. This national experience is then discussed in the light of the global challenges of EWSs considering two main issues:(1) experiences of implementation and barriers related to people-centered warning systems;and(2)types of national/regional warning systems and hazards/threats that are being monitored as an important input for multi-hazard approaches. There are few multi-hazard warning systems in place and EWSs are focused on hydrometeorological hazards, mainly related to floods. The Sendai Framework needs to improve access to data and information, identify views from the frontline, consider political threats and vulnerabilities, and find ways to talk about disaster risk creation processes at a larger scale.

关键词： Risk governance Interdisciplinary research People-centered warning systems

cryotic climate conditions and their eventual implication in the high-mountain surface of the Nevado de Toluca volcano, Mexico

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Journal of Mountain Science 2021年第9期18卷 2273-2286页

作者： SOTO victor Facultad de ciencias Biológicas y Agropecuarias Universidad VeracruzanaPoza Rica-Tuxpan 92870México

The state of the cryosphere in tropical regions is of great importance because the temperature around the glaciers, permafrost and snow cover always fluctuates near the melting point. These thermal conditions and their high sensitivity to climate change cause the accelerated disappearance of these elements;therefore, it is important to know the climatic factors that regulate them, as well as the physical characteristics of each cryospheric element. Unlike glaciers, permafrost and snow cover have not been widely studied. In recent dec.des, the study of the glacial and periglacial environment has been carried out in intertropical mountains. However, despite the altitude of their relief and the frequent occurrence of snowfall in tropical high mountains, the conditions that determine such events have been barely analyzed;and in the case of Mexico, the volume of snowfall and its thickness have not been quantified either, as well as their corresponding duration. consequently, this work is aimed to analyze the temperature and precipitation conditions that determine the snowfall at the higher part of the Nevado de Toluca volcano;at the same time, the conditions of the cryotic climate and their possible implication on the surface are studied. The analysis of data from 1965 to 2016, using frequency statistics, allowed to realize that snowfall occurs with low intensity, its accumulation being less than 10 cm thick and 10 mm of snow water equivalent, which causes the snowpack to stay only a few weeks on average. At the same time, it was determined that there is a significant increase in the number of freeze-thaw cycles. Therefore, due to the climate conditions and their influence on the mountain surface, it is probable that the bedrock is subject to a greater gelifraction dynamics, and the unconsolidated soil surface increases;the combination of the above could cause a greater geomorphological dynamic over time, particularly due to debris flows, and by water and wind erosion of

关键词： Air temperature cryotic conditions High-mountain climatology Periglacial geomorphology Snow precipitation

Ultrashort pulse capability at the L2I high intensity laser facility

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High Power Laser Science and Engineering 2017年第1期5卷 7-11页

作者： Gonqalo Figueira Joana Alves Joao M.Dias Marta Fajardo Nuno Gomes victor Hariton Tayyab Imran celso P.Joao Jayanath Koliyadu Swen Kunzel Nelson c.Lopes hugo Pires Filipe Ruao Gareth Williams GoLP/Instituto de Plasmas e Fusao Nuclear lnstituto Superior TecnieoUniversidade de LisboaLisbonPortugal Faculdade de ciências e Tecnologia Universidade Nova de LisboaCaparicaPortugal department of Physics&Astronomy College of ScienceKing Saud UniversityRiyadhSaudi Arabia

The Laboratory for Intense Lasers(L2I) is a research centre in optics and lasers dedicated to experimental research in high intensity laser science and technology and laser plasma interaction. currently the laboratory is undergoing an upgrade with the goal of increasing the versatility of the laser systems available to the users, as well as increasing the pulse repetition rate. In this paper we review the current status of the laser research and development programme of this facility, namely the upgraded capability and the recent progress towards the installation of an ultrashort, diode-pumped OPcPA laser system.

关键词： diode-pumped solid-state laser and applications femtosecond laser and applications frequency conversion laser amplifiers nonlinear optics

choosing the best endoscopic approach for post-bariatric surgical leaks and fistulas:Basic principles and recommendations

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World Journal of Gastroenterology 2023年第7期29卷 1173-1193页

作者： victor Lira de Oliveira Alexandre Moraes Bestetti Roberto Paolo Trasolini Eduardo Guimaraes Hourneaux de Moura Diogo Turiani Hourneaux de Moura Serviço de Endoscopia Gastrointestinal Departamento de GastroenterologiaHospital das Clínicas da Faculdade de Medicina da Universidade de São PauloSão Paulo 05403010Brazil Division of Gastroenterology Hepatology and EndoscopyHarvard Medical SchoolBrigham and Women's HospitalBostonMA 021115United States

Post-surgical leaks and fistulas are the most feared complication of bariatric *** have become more common in clinical practice given the increasing number of these procedures and can be very difficult to *** two related conditions must be distinguished and characterized to guide the appropriate *** is defined as a transmural defect with communication between the intra and extraluminal compartments,while fistula is defined as an abnormal communication between two epithelialized ***,surgical treatment was the preferred approach for leaks and fistulas and was associated with high morbidity with significant mortality ***,with the development of novel devices and techniques,endoscopic therapy plays an increasingly essential role in managing these *** diagnosis and endoscopic therapy initiation after clinical stabilization are crucial to success since clinical success rates are higher for acute leaks and fistulas when compared to late and chronic leaks and *** endoscopic techniques are available with different mechanisms of action,including direct closure,covering/diverting or *** treatment should be individualized by considering the characteristics of both the patient and the *** there is a lack of high-quality studies to provide standardized treatment algorithms,this narrative review aims to provide a summary of the current scientific evidence and,based on this data and our extensive experience,make recommendations to help choose the best endoscopic approach for the management of post-bariatric surgical leaks and fistulas.

关键词： Endoscopy Surgery Bariatric Gastrointestinal Fistulas Leaks

Recent advances and future challenges for mobile network virtualization

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Science china(Information Sciences) 2017年第4期60卷 5-16页

作者： Xiaofeng TAO Yan HAN Xiaodong XU Ping ZHANG victor c.M.LEUNG National Engineering Lab for Mobile Network Technologies Beijing University of Posts and Telecommunications State Key Lab of Networking & Switching Technology Beijing University of Posts and Telecommunications department of Electrical and computer Engineering The University of British Columbia

Recently, network function virtualization(NFV) was proposed as a paradigm shift in the telecommunication industry. Both industry and ac.demia have drawn significant attention in mobile network *** decouples the software implementation of network functions from the underlying hardware, leading to considerable reductions in operating expenses(OPEX) and capital expenses(cAPEX), and facilitating the network deployment. However, as an emerging technology, NFV brings both challenges and opportunities in developing new architectures, applying and deployment. In this paper, we first survey the related work of NFV, and then propose promising research directions in this area.

关键词： network function virtualization mobile networks software defined networking network functions 5G network slicing

The growth and production modeling of individual trees of Eucalyptus urophylla plantations

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Journal of Forestry Research 2020年第5期31卷 1663-1672页

作者： Joao victor Nobre carrijo Ana Beatriz de Freitas Ferreira Marcela costa Ferreira Mario cesar de Aguiar Eder Pereira Miguel Eraldo Aparecido Trondoli Matricardi Alba Valeria Rezende department of Forestry Faculty of TechnologyUniversity of Brası´liaBrası´lia 70910-900Brazil

Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest *** are more complex than other growth and production models,show a higher level of detail and,consequently,produce a better modeling ***,the accuracy and efficiency of ITMs have not been properly assessed to *** this study,we estimated the growth in height,diameter,and individual tree volume of a Eucalyptus urophylla plantation by applying an *** used a continuing forest inventory dataset in which 1554 individual trees within 29 permanent plots were measured in the field over a 6-year period(24 to 72 months).Each individual tree volume was estimated for future tree *** achieve this,we adjusted the model to predict the height and diameter growth,and the probability of mortality as a function of the competition *** ITM accuracy was assessed based on the analysis of variance results and,subsequently,the multiple mean comparison test at the 5%significance *** tree volumes predicted by the ITM for the forest stand aged 72 months,beginning at ages 24,36,48,and 60 months,were compared to the field measured tree volume acquired from the 72-month forest inventory that was used as the reference *** and observed tree volumes were similar when the estimation was based on the 48-month forest *** results might help to reduce financial costs of forest inventory because the ITM produces accurate future predictions of forest stand *** estimated ITM for Eucalyptus plantations using measurement intervals up to 2 years is recommended because it significantly reduced the projected volume discrepancy compared to the field measurements.

关键词： competition index Forest production Forest site Simulation models Tree mortality

高延性纤维增强水泥基复合材料的研究进展及应用

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硅酸盐学报 2007年第4期35卷 531-536页

作者： LI victor c department of Materials Science and Engineering the University of Michigan Ann Arbor MI 48109-2125 USA

高延性水泥基复合材料(engineered cementitious composite,Ecc)是经系统的微观力学设计,在拉伸和剪切荷载下呈现高延展性的一种纤维增强水泥基复合材料。综述了Ecc的研究进展,介绍了配筋Ecc结构的耐久性、安全性及可持续性等混凝土必... 详细信息

高延性水泥基复合材料(engineered cementitious composite,Ecc)是经系统的微观力学设计,在拉伸和剪切荷载下呈现高延展性的一种纤维增强水泥基复合材料。综述了Ecc的研究进展,介绍了配筋Ecc结构的耐久性、安全性及可持续性等混凝土必须满足的关键性能。根据Ecc近来的应用情况及在工程上推广应用的需要,总结了Ecc长期性能方面的研究结果。

关键词：复合材料纤维延展性耐久性可持续性安全性设计基础设施