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Genetic structure of the whitefly Bemisia tabaci populations in Colombia following a recent invasion

作者： nancy

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Insect Science 2015年第4期22卷 483-494页

作者： Fernando Dfaz nancy M. Endersby Ary A. Hoffmann Department of Biology Universidad del Valle Cali Colombia Department of Genetics Pest and Disease Vector Group Bio 21 Institute University of Melboume Parkville Victoria 301 0 Australia

The whitefly Bemisia tabaci （Gennadius） is one of the most important pests causing economic losses in a variety of cropping systems around the world. This species was recently found in a coastal region of Colombia and has now spread inland. To investigate this invasive process, the genetic structure of B. tabaci was examined in 8 sampling locations from 2 infested regions （coastal, inland） using 9 microsatellite markers and the mitochondrial COI gene. The mitochondrial analysis indicated that only the invasive species of the B. tabaci complex Middle East-Asia Minor 1 （MEAM 1 known previously as biotype B） was present. The microsatellite data pointed to genetic differences among the regions and no isolation by distance within regions. The coastal region in the Caribbean appears to have been the initial point of invasion, while the inland region in the Southwest showed genetic variation among populations most likely reflecting founder events and ongoing changes associated with climatic and topographical heterogeneity. These findings have implications for tracking and managing B. tabaci.

关键词： Bemisia tabaci Colombia microsatellites Middle East-Asia Minor 1(MEAM 1) mtCOI population structure

The Emergence of a Globalized System for Disaster Risk Management and Challenges for Appropriate Governance

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International Journal of Disaster Risk Science 2015年第1期6卷 87-93页

作者： Steven JJensen Shirley Feldmann-Jensen David MJohnston nancy ABrown College of Health and Human Services California State University GNS Science School of Psychology Joint Centre of Disaster ResearchMassey University

Disaster risk management(DRM) is undergoing noteworthy changes, reflecting the broader shifts in global and local levels of governance. At the global level two significant changes are of interest:(1) the shift from monolithic structures of global governance to a wide range of organizations that can be brought together for specific purposes and(2) the emergence of a globalized system of DRM, with technological, organizational, and institutional capacities enhancing DRM’s ability as a unit in near real time across the globe. At the local level there is an increase in ability to govern and develop creative solutions for complex problems that follow rapid urbanization. The importance of getting the global–local interface to work in tandem has been highlighted by recent hazard events, such as the 2011 Tohoku Earthquake and Tsunami. From a broad view of global and local shifts, a strategic role is becoming clearer at the national level for enhancing the relationships between the global and local levels. Through the influence of a globalized system of DRM, the local level can significantly improve its capacity without the heavy investment that might have been required to develop these capacities in isolation. One key to achieving this is adiffusion of DRM higher education, supported by an enhanced system of information flow.

关键词： Disaster risk management Global governance Globalization Globalized systems Local governance National governance

Dynamic Routing Optimization Algorithm for Software Defined Networking

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Computers, Materials & Continua 2022年第1期70卷 1349-1362页

作者： nancy Abbas El-Hefnawy Osama Abdel Raouf Heba Askr Department of Information Systems Tanta UniversityTanta31511Egypt Department of Operations Research and Decision Support Menoufia UniversityShepen AlkomEgypt Department of Information Systems University of Sadat CityAlSadat City048Egypt

Time and space complexity is themost critical problemof the current routing optimization algorithms for Software Defined Networking(SDN).To overcome this complexity,researchers use meta-heuristic techniques inside the routing optimization algorithms in the OpenFlow(OF)based large scale *** paper proposes a hybrid meta-heuristic algorithm to optimize the dynamic routing problem for the large scale *** to the dynamic nature of SDNs,the proposed algorithm uses amutation operator to overcome the memory-based problem of the ant colony ***,it uses the box-covering method and the k-means clustering method to divide the SDN network to overcome the problemof time and space *** results of the proposed algorithm compared with the results of other similar algorithms and it shows that the proposed algorithm can handle the dynamic network changing,reduce the network congestion,the delay and running times and the packet loss rates.

关键词： Dynamic routing optimization Openflow software defined networking

Effect of Co on Microstructure Transformation and Refinement Mechanism of Undercooled Cu-Ni Alloy

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 877-884页

作者： Willey Liew Yun Hsien 安洪恩 nancy Julius Siambun Bih-Lii Chuab Faculty of Engineering University Malaysia SabahKota Kinabalu88400Malaysia College of Mechanical and Electronic Engineering Huanghe Jiaotong UniversityJiaozuo454950China Henan Engineering Technology Research Center on Intelligent Manufacturing Technology and Equipment Jiaozuo454950China

Both Cu60Ni38Co2 and Cu60Ni40 alloy were naturally cooled after rapid solidification from the liquid *** transformation law of the microstructure characteristics of the rapidly solidified alloy with the change of undercooling(DT)was systematically *** was found that the two alloys experienced the same transformation *** refinement structures under different undercoolings were characterized by electron backscatter diffraction(EBSD).The experimental results show that the characteristics of the refinement structure of the two alloys with low undercooling are the same,whereas,the characteristics of the refinement structure with high undercooling are *** transmission electron microscope(TEM)results of Cu60Ni38Co2 alloy show that the dislocation network density of low undercooled microstructure is lower than that of high undercooled *** combining EBSD and TEM,it can be confirmed that the dendrite remelting fracture is the reason for the refinement of the low undercooled structure,while the high undercooled structure is refined due to recrystallization.

关键词： rapid solidification undercooling microstructure refinement structure

Almost primes in short intervals

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Science China Mathematics 2010年第9期53卷 2511-2524页

作者： WU Jie Institut Elie Cartan nancy,CNRS,nancy-Université,INRIA,Boulevard des Aiguillettes,B.P.239,54506 Vand CEuvre-lès-nancy,France Institut Elie Cartan nancy CNRS Nancy-Universite INRIA Boulevard des Aiguillettes

In this paper,we prove that the short interval(x-x101/232,x] contains at least an almost prime P2 for sufficiently large x,where P2 denotes an integer having at most two prime factors counted with multiplicity.

关键词： estimates on exponential sums distribution of integers with specified multiplicative constraints applications of sieve methods

On the Convergence Rate of an Inexact Proximal Point Algorithm for Quasiconvex Minimization on Hadamard Manifolds

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Journal of the Operations Research Society of China 2017年第4期5卷 457-467页

作者： nancy Baygorrea Erik Alex Papa Quiroz Nelson Maculan Federal University of Rio de Janeiro PESC-COPPE-UFRJPO Box 68511Rio de Janeiro CEP 21941-972Brazil

In this paper,we present an analysis about the rate of convergence of an inexact proximal point algorithm to solve minimization problems for quasiconvex objective functions on Hadamard *** prove that under natural assumptions the sequence generated by the algorithm converges linearly or superlinearly to a critical point of the problem.

关键词： Proximal point method Quasiconvex function Hadamard manifolds Nonsmooth optimization Abstract subdifferential Convergence rate

A Survey on Parallel Computing and its Applications in Data-Parallel Problems Using GPU Architectures

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Communications in Computational Physics 2014年第2期15卷 285-329页

作者： Cristobal A.Navarro nancy Hitschfeld-Kahler Luis Mateu Department of Computer Science(DCC) Universidad de ChileSantiagoChile Centro de Estudios Cient´ıficos(CECS) ValdiviaChile.

Parallel computing has become an important subject in the field of computer science and has proven to be critical when researching high performance *** evolution of computer architectures(multi-core and many-core)towards a higher number of cores can only confirm that parallelism is the method of choice for speeding up an *** the last decade,the graphics processing unit,or GPU,has gained an important place in the field of high performance computing(HPC)because of its low cost and massive parallel processing ***-computing has become,for the first time,available to anyone at the price of a desktop *** this paper,we survey the concept of parallel computing and especially GPU *** efficient parallel algorithms for the GPU is not a trivial task,there are several technical restrictions that must be satisfied in order to achieve the expected *** of these limitations are consequences of the underlying architecture of the GPU and the theoretical models behind *** goal is to present a set of theoretical and technical concepts that are often required to understand the GPU and its massive parallelism *** particular,we show how this new technology can help the field of computational physics,especially when the problem is *** present four examples of computational physics problems;n-body,collision detection,Potts model and cellular automata *** examples well represent the kind of problems that are suitable for GPU *** understanding the GPU architecture and its massive parallelism programming model,one can overcome many of the technical limitations found along the way,design better GPU-based algorithms for computational physics problems and achieve speedups that can reach up to two orders of magnitude when compared to sequential implementations.

关键词： GPU computing parallel computing computing models algorithms data parallel massive parallelism Potts model Ising Model collision detection n-body Cellular Automata.

Inexact Proximal Point Methods for Quasiconvex Minimization on Hadamard Manifolds

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Journal of the Operations Research Society of China 2016年第4期4卷 397-424页

作者： nancy Baygorrea Erik Alex Papa Quiroz Nelson Maculan Federal University of Rio de Janeiro PESC-COPPE-UFRJPO Box 68511Rio de Janeiro CEP 21941-972Brazil

In this paper we present two inexact proximal point algorithms to solve minimization problems for quasiconvex objective functions on Hadamard *** prove that under natural assumptions the sequence generated by the algorithms are well defined and converge to critical points of the *** also present an application of the method to demand theory in economy.

关键词： Proximal point method Quasiconvex function Hadamard manifolds Nonsmooth optimization Abstract subdifferential