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Experimental study of sand grains behavior at their contacts with force-and displacement-controlled sliding tes.s

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Underground space 2017年第1期2卷 38-44页

作者： K.senetakis C.s.sandeep City University of Hong Kong Hong Kong

Discrete element modeling requires the proper quantification of the behavior of grains at their contacts including the normal force-displacement and tangential force-displacement relationships to be used as input for contact modeling *** paper reports on recent advances in soil mechanics experimentation which allowed measuring the grain contact behavior of small sand particles quantifying friction and stiffness with sliding tes.s of a force-controlled or displacement-controlled *** particular focus of this work is on the micromechanical behavior of quartz type grains of size between about 1 and 5 mm.A description of the developed micromechanical apparatus at City University of Hong Kong is first discussed and its important different capabilities with previously developed apparatus is briefly ***,a limited set of new data is reported and discussed along with a review of recently acquired results published in the literature associated with the contact behavior of quartz sand *** sliding tes.s have covered a wider range of normal contact forces from about 0.5 to 8 N,and the results indicated that,for this range of confining forces,there is not any notable change of the inter-particle coefficient of friction.

关键词： Micro-mechanics Inter-particle friction Inter-particle stiffness LBs grains Experimental mechanics

Long-term monitoring data reveal effects of age,population density,and environmental aspects on hatching success of Common Cranes(Grus grus)

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Avian Research 2022年第3期13卷 347-355页

作者： Isabel Barwisch Wolfgang Mewes Angela schmitz Ornes AG Vogelwarte Zoological Institute and MuseumUniversity of GreifswaldSoldmannstr.23GreifswaldGermany Grüner Weg 3 19395Plau Am SeeOT KarowGermany

Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its *** drainage and intensification of agriculture and forestry set wetlands and associated species at risk of population *** population of Common Cranes(Grus grus)has experienced considerable fluctuations over the last *** increasing population numbers,hatching success.seemed to have decreased over the last *** aim of this.study was to identify factors influencing hatching success and nest survival of Common Cranes based on analys.s of long-term individual-based monitoring data from northeastern Germany and evaluate the species ability to adapt to changing *** success decreased over the course of the study period from 0.75 to ***,nest survival and hatching success did not vary across different nesting habitats,whereas factors.such as female age,timing of nest initiation and breeding pair density were found to have significant effects on hatching *** females.showed higher hatching success,even though the proportion of unhatched eggs was highest in females aged 20 years or *** nest initiation had a positive effect on hatching *** levels are more favorable early in the nesting season,whereas increasing evaporation with time caus.s water levels to decrease,granting easier access for *** of female age,hatching success decreased with increasing numbers of breeding pairs within a 2-km radius around a nesting *** population densities intensify competition for resources and promote intraspecific interactions,affecting reproductive outcome *** study gives first insights into mechanis.s behind population regulation in Common Cranes,highlighting the importance of population dynamics and individual *** suggest to further investigate density dependent effects including landscape and habitat features as well as reproduct

关键词： Adaptation Age Cranes Grus grus Habitat Nest survival Population density Reproduction

shocks and solitons in Ultradense Degenerate Electron-Positron-Ion Plasmas

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Communications in Theoretical Physics 2011年第1期55卷 151-157页

作者： s.A.Khan Arshad M.Mirza National Centre for Physics Quaid-i-Azam University Campusand Department of PhysicsCOMSATS Institute of Information Technology Theoretical Plasma Physics Group Department of PhysicsQuaid-i-Azam University

震动和 solitons 的形成和繁殖被雇用 Thomas 费密模型在 unmagnetized，包含电子和正电子的退化费密气体的 ultradense 血浆，和古典离子气体调查。为这个目的，一个使变形的 Korteweg-de Vries 冰山(dKdVB ) 方程为冷、断热、等温的... 详细信息

震动和 solitons 的形成和繁殖被雇用 Thomas 费密模型在 unmagnetized，包含电子和正电子的退化费密气体的 ultradense 血浆，和古典离子气体调查。为这个目的，一个使变形的 Korteweg-de Vries 冰山(dKdVB ) 方程为冷、断热、等温的离子用减少的 perturbative 技术被导出。在平面几何学的 dKdVB 方程的局部性的分析答案为分散以及驱散被获得主导的案例。为 nonplanar (圆柱、球形) 几何学，改变 dKdVB 方程的数字冲击波答案的时间被发现。它导致 soliton 答案的主导的大小写也是的分散讨论了。离子温度，正电子集中和驱散的效果在这些非线性的结构上被发现重要。到科学兴趣的系统的结果的关联被指出。

关键词：正负电子对等离子体孤子解超密 KdVB方程等离子气体退化 KdV方程

Generalized Multiobjective symmetric Duality under second-Order(F, α, ρ, d)-Convexity

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Acta Mathematicae Applicatae sinica 2015年第2期31卷 529-542页

作者： s.K.Gupta D.Dangar Department of Mathematics Indian Institute of Technology Roorkee Department of Mathematics and Humanities IT Nirma University

In this paper, we first formulate a second-order multiobjective symmetric primal-dual pair over arbitrary cones by introducing two different functions f ： R^n × R^m → Rk and g ： R^n × R^m → R^l in each k-objectives as well as l-constraints. Further, appropriate duality relations are established under second-order（F, α, ρ, d）-convexity assumptions. A nontrivial example which is.second-order（F, α, ρ, d）-convex but not secondorder convex/F-convex is also illustrated. Moreover, a second-order minimax mixed integer dual programs is formulated and a duality theorem is established using second-order（F, α, ρ, d）-convexity assumptions. A self duality theorem is also obtained by assuming the functions involved to be skew-symmetric.

关键词： multiobjective symmetric duality second-order(F α ρ d)-convex duality theorems minimax self duality

Mixed finite element and differential quadrature method for free and forced vibration and buckling analys.s of rectangular plates

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Applied Mathematics and Mechanics(English Edition) 2012年第1期33卷 81-98页

作者： s. A. EFTEKHARI A. A. JAFARI Department of Mechanical Engineering K. N. Toosi University of Technology

This paper presents a combined application of the finite element method （FEM） and the differential quadrature method （DQM） to vibration and buckling problems of rectangular plates. The proposed scheme combines the geometry flexibility of the FEM and the high accuracy and efficiency of the DQM. The accuracy of the present method is demonstrated by comparing the obtained results with those available in the literature. It is.shown that highly accurate results can be obtained by using a small number of finite elements and DQM sample points. The proposed method is.suitable for the problems considered due to its.simplicity and potential for further development.

关键词： finite element method (FEM) differential quadrature method (DQM) rectangular plate free and forced vibration buckling analys.s

ON A CLAss OF ANALYTIC FUNCTIONs RELATED TO CONIC DOMAINs AND AssOCIATED WITH CARLsON-sHAFFER OPERATOR

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Acta Mathematica scientia 2012年第4期32卷 1399-1407页

作者： s.Hussain J.sokól Mathematics Department COMSATS Institute of Information TechnologyAbbottabadPakistan Department of Mathematics Rzeszów University of Technologyul.W.Pola 235-959 RzeszówPoland

Making use of the Carlson-shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. some applications are also discussed.

关键词： Hadamard product (or convolution) differential subordination Carlson-shaffer operator k-starlike functions k-uniformly convex function

Analytical Hopf Bifurcation and stability Analys.s of T s.stem

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Communications in Theoretical Physics 2011年第4期55卷 609-616页

作者： Robert A.VanGorder s.Roy Choudhury Department of Mathematics University of Central Florida

复杂动力学在 T 系统被学习，一个三维的自治非线性的系统。特别地，我们执行系统的扩大 Hopf 分叉分析。立即跟随 Hopf 分叉的周期的轨道是为用多重规模的方法的 T 系统的构造经分解，并且如此的轨道的稳定性被分析。如此的分析结果补... 详细信息

复杂动力学在 T 系统被学习，一个三维的自治非线性的系统。特别地，我们执行系统的扩大 Hopf 分叉分析。立即跟随 Hopf 分叉的周期的轨道是为用多重规模的方法的 T 系统的构造经分解，并且如此的轨道的稳定性被分析。如此的分析结果补充在文学在场的数字结果。在分叉以后的政体的分析结果经由数字模拟被验证并且延长，以及由标准力量系列，自相关功能，和分数维的尺寸诊断的使用。我们发现 T 系统在许多参数政体展出有趣的行为。

关键词： Hopf分岔非线性系统稳定性分析周期轨道自相关函数分岔分析解析方法数值结果

An ass.ssment of interspecific competition between two introduced parasitoids of Diaphorina citri (Hemiptera: Liviidae)on caged citrus plants

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Insect science 2019年第1期26卷 119-127页

作者： Meghan A.Vankosky Mark s.Hoddle Department of Entomology University of CalifomiaRiversideCalifomiaUSA Center for Invasive species Research University of CaliforniaRiversideCaliforniaUSA

Two parasitoids attacking nymphs of Asian citrus psyllid,Diaphorina citri Kuwayama (Hemiptera:Liviidae),Tamarixia radiata (Waterston)(Hymenoptera:Eulophi- dae)and Diaphoreneyrtus aligarhens.s (shafee,Alam &Agarwal)(Hymenoptera:Encyrtidae)are being released in California,UsA in a classical biological control program. To evaluate the effect of multiple parasitoid species on *** mortality,we conducted mesocosm experiments under controlled conditions using a complete block design with 6 treatments (*** nymphs exposed to:no parasitoids;*** or *** alone;*** or *** released first (by 48 h);and both species released simultaneously).Parasitism of *** nymphs by *** exceeded 60%and was unchanged when *** were *** by *** was greatest when T. radiata was absent (-28%)and was reduced in all treatments with *** present (sitoid-related mortality *** was cons.stent across parasitoid *** results.suggest that competition between *** and *** is asymmetric and favors *** may be difficult for *** to contribute significantly to *** biological control where *** is ***, results reported here suggest that competition between *** and *** is not likely to reduce parasitism by *** or reduce parasitoid-induced mortality of ***.

关键词： Asian citrus psyllid classical biological control competition Diaphorencyrtus aligarhens.s Tamarixia radiata

The Influence of s.stematic Errors on the Asian summer Monsoon Circulation

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Advances in Atmospheric sciences 2000年第4期17卷 576-586页

作者： P. L. s. Rao IBM India Research Laboratory Indian Institute of Technology

The s.stematic errors of wind field associated with the prediction of Asian summer monsoon and their impact on the monsoon circulation have been studied in this paper. The daily operational analys.s and fore-cas.s (up to day-5) of the National Centre for Medium Range Weather Forecasting (NCMRWF), India, over the Asian summer monsoon domain for the period June, July and August of 1995 are made use for the purpose. The s.stematic errors associated with the low level flow delineate, reduction in the strength of trade winds leading to weakening of cross equatorial flow as well as westerly flow over Indian Ocean. The upper level errors connote weakening of Tibetan anticyclone and reduction in the strength of return flow into the southern Hemisphere. Further, these errors evince growing tendency with increase in the forecast period. Apart from the general underestimation of kinetic energy budget terms, the model forecas.s fail to represent the transient eddies. The forecas.s show increasing trend in the conversion of eddy to mean kinetic energy. These errors enfeeble Asian summer monsoon circulation with increase in the forecast period. Key words Monsoon - s.stematic errors - Kinetic energy budget The author is grateful to the NCMRWF for providing data and computing facilities to carry out the present study.

关键词： Monsoon s.stematic errors Kinetic energy budget