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Journal of Donghua University(English Edition) 2017年第2期34卷 178-183页

作者：闫春雷杨舒先 College of Mathematics and statistics Qingdao UniversityQingdao 266071China

A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,sufficient optimality conditions and MondWeir type dual theorems are derived for a class of nondifferentiable multiobjective fractional programming problems in which every component of the objective function and each constraint function contain a term involving the support function of a compact convex set.

关键词： nondifferentiable multiobjective fractional programming efficiency (Φ,ρ,α)-V-invexity sufficiency duality

sufficiency Economy for Sustainable Human Resource Development in Tourism Business

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Journal of Tourism and Hospitality Management 2018年第1期6卷 17-22页

作者： Khewika Sukiam Kasetsart University BangkokThailand

The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from literature review,the meaning of sufficiency economy philosophy,sustainable development and human resource.The result has shown that the sufficiency economy philosophy is a measure of well-being(Nothing can be developed sustainably like HRD.Tourism business is a service product that depends on human resources).That is the reason why the sufficiency economy philosophy should be implemented for sustainable HRD in tourism business.

关键词： sufficiency economy sustainable human resource development(HRD) tourism business

Taxonomy-based differences in feeding guilds of fish

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Current Zoology 2020年第1期66卷 51-56页

作者： Javier SANCHEZ-HERNANDEZ Departamento de Zooloxla Xenetica e Antropoloxfa FlsicaFacultade de BioloxfaUniversidade de Santiago de CompostelaCampus Vida s/nSantiago de CompostelaEspana

It has been taken for granted that feeding guilds and behavior in animals are linked to the taxonomic relatedness of species,but empirical evidence supporting such relationship is virtually missing.To examine the importance of taxonomy on trophic ecology,I here present the first well-resolved dietary taxonomy analysis based on feeding guilds(predation,herbivory,and filtering)among families and genera within the fish order Perciformes.Taxonomic relatedness in feeding did not vary with ecosystem dimension(marine vs.freshwater).Although predation dominates among Perciformes fishes,this study shows that in most cases taxonomic units(family or genus)are composed by species with several feeding guilds.Related species are more similar in feeding compared with species that are taxonomically more distant demonstrating that there is a greater variation of feeding guilds within families than genera.Thus,there is no consistency in feeding guilds between family-and genus-level taxonomy.This study provides empirical support for the notion that genera are more informative than families,underlining that family-level taxonomy should be avoided to infer feeding habits of fish species at finer taxonomic resolution.Thus,the choice of taxonomic resolution(family or genus level)in ecological studies is key to avoid information loss and misleading results.I conclude that high-rank taxonomic units(i.e.,above the generic level)are not appropriate to test research hypotheses about the feeding of fish.

关键词： aquatic systems clades FishBase global datasets taxonomic sufficiency trophic ecology

Optimal vector-valued intensity measure for seismic collapse assessment of structures

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 37-54页

作者： Masood Yakhchalian Ahmad Nicknam Gholamreza Ghodrati Amiri School of Civil Engineering Iran University of Science & Technology Center of Excellence for Fundamental Studies in Structural Engineering School of Civil Engineering Iran University of Science & Technology

The present study is aimed to investigate the ability of different intensity measures （IMs）, including response spectral acceleration at the fundamental period of the structure, Sa（T1）, as a common scalar IM and twelve vector-valued IMs for seismic collapse assessment of structures. The vector-valued IMs consist of two components, with S（T1） as the first component and different parameters that are ratios of scalar IMs, as well as the spectral shape proxies εSa and N, as the second component. After investigating the properties of an optimal IM, a new vector-valued IM that includes the ratio of Sa（T1） to the displacement spectrum intensity （DSI） as the second component is proposed. The new IM is more efficient than other IMs for predicting the collapse capacity of structures. It is also sufficient with respect to magnitude, source-to-site distance, and scale factor for collapse capacity prediction of structures. To satisfy the predictability criterion, a ground motion prediction equation （GMPE） is determined for Sa（T1）/DSI by using the existing GMPEs. Furthermore, an empirical equation is proposed for obtaining the correlation between the components of the proposed IM. The results of this study show that using the new vector-valued IM leads to a more reliable seismic collapse assessment of structures.

关键词： intensity measure efficiency sufficiency displacement spectrum intensity collapse capacity fragility surface

Study on Ground Motion Intensity Measures for Seismic Response Evaluation of Circular Tunnel

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Study on Ground Motion Intensity Measures for Seismic Respon...

Efficiency and Duality in Nondifferentiable Multiobjective Programming Involving Directional Derivative

作者： Chengming Zhang Zilan Zhong Mi Zhao Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Technology

Ground motion intensity measure（IM） is a key link between the seismic hazard analysis and structural seismic response analysis,which play an important role in the performance-based earthquake engineering framework.In order to find suitable IM for seismic response evaluation of circular tunnel,nonlinear dynamic time-history analyses are conducted on a two-dimensional finite element model of tunnel-surrounding rock interaction in this study.The near field ground motions without velocity pulse and far field ground motions as recommended by FEMA-P695 are used as the input ground motions for the numerical model.Besides,the overall lining damage indices in compression and in tension are used as engineering damage measures（DMs） to estimate the lining damage state.The applicability of 20 existing ground motion IMs commonly used in engineering practice are investigated in this study.Statistically regression analysis is carried out for results obtained from nonlinear time-history analyses.Based on the criteria of efficiency and sufficiency,Arias intensity is identified as the optimal IM for seismic response prediction of circular tunnel structure.

关键词： intensity measure circular tunnel efficiency sufficiency nonlinear dynamic analysis

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Applied Mathematics 2011年第4期2卷 452-460页

作者： Izhar Ahmad Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals

In this paper, we introduce a new class of generalized dI-univexity in which each component of the objective and constraint functions is directionally differentiable in its own direction di for a nondifferentiable multiobjective programming problem. Based upon these generalized functions, sufficient optimality conditions are established for a feasible point to be efficient and properly efficient under the generalised dI-univexity requirements. Moreover, weak, strong and strict converse duality theorems are also derived for Mond-Weir type dual programs.

关键词： Multiobjective Programming Nondifferentiable Programming Generalized dI-Univexity sufficiency Duality

On the Choice of Reading Materials in TESL

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Sino-US English Teaching 2019年第10期16卷 415-418页

作者： CHE Ningwei Beijing International Studies University BeijingChina

The choice of reading materials partly decides the effectiveness of classroom reading instructions in TESL.This paper analyses the cognitive process of reading and some problems in classroom reading instructions of reading course,and suggests three basic principles for choosing reading materials,including the principle of comprehensibility reading materials,readers’familiarity with the topics of the reading materials,and the sufficiency of reading materials.

关键词： reading materials comprehensibility familiarity sufficiency