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Developing a modeling tool for flow profiling in irrigation distribution networks

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International Journal of Agricultural and Biological Engineering 2009年第3期2卷 17-26页

作者： Yanbo Huang guy Fipps Application and Production Technology Research Unit US Department of AgricultureAgricultural Research Service(USDA-ARS)StonevilleMS 38776USA Department of Biological and Agricultural Engineering Texas A&M UniversityCollege StationTX 77843USA

Efforts are underway to rehabilitate the irrigation districts,such as in the Rio Grande Basin in *** distribution network models are needed to help prioritize and analyze various rehabilitation options,as well as to scientifically quantify irrigation water demands,usages,and losses,and to help manage gate ***,commercially available software packages were limited in applications due to their high cost and operational *** study aims to develop a modeling tool for modeling the water flow profile in irrigation distribution *** goal of developing the modeling tool was to make the modeling process simple,fast,reliable and *** the basis of methodological study,the modeling tool has been developed for branching canal networks with the assumption of steady gradually varied *** flow profile calculation of the tool was verified from a single channel with 1%root mean squared error compared to the benchmark calculation and a branching network with 5%to 12%relative errors compared to check point measurement along the *** developed modeling tool will be able to play an important role in water quantification for planning,analysis and development for modernization of irrigation systems.

关键词： irrigation distribution network modeling tool flow profiling

AdS/QCD and light front holography: A new approximation to QCD

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Chinese Physics C 2010年第9期34卷 1229-1235页

作者： Stanley J.Brodsky guy F.de Téramond SLAC National Accelerator Laboratory Stanford University Universidad de Costa Rica

The combination of Anti-de Sitter space （AdS） methods with light-front holography leads to a semi-classical first approximation to the spectrum and wavefunctions of meson and baryon light-quark bound *** from the bound-state Hamiltonian equation of motion in QCD,we derive relativistic lightfront wave equations in terms of an invariant impact variable ζ which measures the separation of the quark and gluonic constituents within the hadron at equal light-front *** equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti–de Sitter （AdS） *** eigenvalues give the hadronic spectrum,and its eigenmodes represent the probability distributions of the hadronic constituents at a given *** to the light meson and baryon spectra are *** predicted meson spectrum has a string-theory Regge form M^ 2 = 4κ ^2 （n＋L＋S/2）;i.e.,the square of the eigenmass is linear in both L and n,where n counts the number of nodes of the wavefunction in the radial variable ζ.The space-like pion and nucleon form factors are also well *** thus obtains a remarkable connection between the description of hadronic modes in AdS space and the Hamiltonian formulation of QCD in physical space-time quantized on the light-front at fixed light-front time τ.The model can be systematically improved by using its complete orthonormal solutions to diagonalize the full QCD lightfront Hamiltonian or by applying the Lippmann-Schwinger method in order to systematically include the QCD interaction terms.

关键词： gauge/gravity correspondence light-front dynamics strongly coupled QCD meson and baryon spectrum meson and nucleon form factors

A review on barrier layers used in flexible stainless-steel based CIGS photovoltaic devices

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npj Flexible Electronics 2023年第1期7卷 187-198页

作者： Sarallah Hamtaei guy Brammertz Jef Poortmans Bart Vermang imec imo-imomecThor Park 83203600 GenkBelgium Hasselt University(partner in Solliance) imo-imomecMartelarenlaan 423500 HasseltBelgium EnergyVille imo-imomecThor Park 83203600 GenkBelgium KU Leuven Department of Electrical EngineeringKasteelpark Arenberg 103001 HeverleeBelgium

Two primary engineering challenges are en route to fabricating high-performance flexible stainless-steel based Cu(In,Ga)(S,Se)_(2)solar cells;Growing absorbers without contamination from the substrate,and providing alkali dopants to the *** former is chiefly addressed by introducing a barrier layer,and the latter by post-deposition treatment or including dopant-containing layers in the *** we organize these solutions and different approaches in an accessible ***,reports on interaction between contamination and alkali elements are discussed,as is the impact of barrier layer properties on the interconnect ***,we make recommendations to consolidate the multitude of sometimes inharmonious solutions.

关键词： CIGS barrier absorber

Determinants of vigilance in a reintroduced population of Pere David＇s deer

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Current Zoology 2013年第2期59卷 265-270页

作者： Wei ZHENG guy BEAUCHAMP Xuelei JIANG Zhongqiu LI Qinglong YANG The State Key Laboratory of Pharmaceutical B iotechnology School of Life Science Nanjing University Nanjing 210093 China Faculty of Veterinary Medicine University of Montreal St-Hyacinthe Quebec Canada J2S 7C6 Jinling College Nanjing University Nanjing 210089 China

After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David＇s deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential threat. Antipredator vigilance i~ an important component of survival for many prey animals in their natural habitat. Do deer still adjust vigilance as a function of risk after such a long period of relaxed predation pressure？ Here, we examined vigilance levels in P6re David＇s deer groups as a function of group size, sex and level of human disturbance. The results showed that individual vigilance significantly decreased with group size in all-female groups but not in all-males or mixed-sex groups. In rutting season, males compete with one another and harass females, and we argue that vigilance is partly aimed at threatening males and that such vigilance increases with group size. This explains why overall vigilance did not vary with group size for males in general and for females in mixed-sex groups. Vigilance increased in more disturbed areas but in in male deer only. The results indicate that despite relaxed predation pressure over centuries, P6re David＇s deer can still adjust antipredator responses as a function of perceived risk. Such information may become useful in the rewilding programme now under way for this species in China [Current Zoology 59 （2）： 265-270, 2013].

关键词： Antipredator vigilance Group size Human disturbance Sexual competition P6re David's deer

Is atmospheric oxidation capacity better in indicating tropospheric O_(3) formation?

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Frontiers of Environmental Science & Engineering 2022年第5期16卷 127-133页

作者： Peng Wang Shengqiang Zhu Mihalis Vrekoussis guy PBrasseur Shuxiao Wang Hongliang Zhang Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200438China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science&EngineeringFudan UniversityShanghai 200438China Institute of Environmental Physics University of BremenBremen D-28359Germany Climate and Atmosphere Research Center(CARE-C) the Cyprus InstituteNicosia 27456Cyprus Max Planck Institute for Meteorology Hamburg 20146Germany National Center for Atmospheric Research BoulderCO 80307USA State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Institute of Eco-Chongming(IEC) Shanghai 202162China

Tropospheric ozone(O_(3))concentration is increasing in China along with dramatic changes in precursor emissions and meteorological conditions,adversely affecting human health and ecosystems.O_(3) is formed from the complex nonlinear photochemical reactions from nitrogen oxides(NOx=NO+NO_(2))and volatile organic compounds(VOCs).Although the mechanism of O_(3) formation is rather clear,describing and analyzing its changes and formation potential at fine spatial and temporal resolution is still a challenge *** this study,we briefly summarized and evaluated different approaches that indicate O_(3) formation *** identify that atmospheric oxidation capacity(AOC)is a better indicator of photochemical reactions leading to the formation of O_(3) and other secondary *** show that AOC has a prominent positive relationship to O_(3) in the major city clusters in China,with a goodness of fit(R^(2))up to *** outcome provides a novel perspective in characterizing O_(3) formation and has significant implications for formulating control strategies of secondary pollutants.

关键词： O_(3) AOC O_(3) formation regime

Exact solitary wave solutions of a nonlinear Schrdinger equation model with saturable-like nonlinearities governing modulated waves in a discrete electrical lattice

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Chinese Physics B 2018年第12期27卷 420-430页

作者： Serge Bruno Yamgoue guy Roger Deffo Eric Tala-Tebue Francois Beceau Pelap Department of Physics Higher Teacher Training College BambiliThe University ofBamendaP.O.Box 39Bamenda Cameroon Unite de Recherche de Mecanique et de Modelisation des Systemes Physiques (UR-2MSP) Faculte des SciencesUniversite de DschangBP 69DschangCameroun Department of Telecommunication and Network Engineering Fotso Victor University Institute of TechnologyThe University of DschangP.O.Box 134BandjounCameroon

In this paper, we introduce and propose exact and explicit analytical solutions to a novel model of the nonlinear Schr¨odinger(NLS) equation. This model is derived as the equation governing the dynamics of modulated cutoff waves in a discrete nonlinear electrical lattice. It is characterized by the addition of two terms that involve time derivatives to the classical equation. Through those terms, our model is also tantamount to a generalized NLS equation with saturable;which suggests that the discrete electrical transmission lines can potentially be used to experimentally investigate wave propagation in media that are modeled by such type of nonlinearity. We demonstrate that the new terms can enlarge considerably the forms of the solutions as compared to similar NLS-type equations. Sine–Gordon expansion-method is used to derive numerous kink, antikink, dark, and bright soliton solutions.

关键词： nonlinear Schrdinger equation nonlinear time derivative terms saturable nonlinearity exact solitary solutions

Exact transverse solitary and periodic wave solutions in a coupled nonlinear inductor-capacitor network

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Chinese Physics B 2018年第9期27卷 434-443页

作者： Serge Bruno Yamgoué guy Roger Deffo Eric Tala-Tebue Francois Beceau Pelap Department of Physics Higher Teacher Training College Bambili the University of Bamenda Unité de Recherche de Mécanique et de Modélisation des Systèmes Physiques (UR-2MSP) Faculté des Sciences Université de Dschang Department of Telecommunication and Network Engineering Fotso Victor University Institute of Technology The University of Dschang P.O. Box 134 Bandjoun Cameroon

Through two methods, we investigate the solitary and periodic wave solutions of the differential equation describing a nonlinear coupled two-dimensional discrete electrical lattice. The fixed points of our model equation are examined and the bifurcations of phase portraits of this equation for various values of the front wave velocity are presented. Using the sineGordon expansion method and classic integration, we obtain exact transverse solutions including breathers, bright solitons,and periodic solutions.

关键词： nonlinear electrical lattices two-dimensional network sine-Gordon expansion exact transverse solitary wave solutions

Applications of next-generation sequencing to the study of biological invasions

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Current Zoology 2015年第3期61卷 488-504页

作者： Marc RIUS Steve BOURNE Harry guy HORNSBY Mark A. CHAPMAN Ocean and Earth Science National Oceanography Centre Southampton University of Southampton SO 14 3ZH UK Centre for Biological Sciences Life Sciences Building 85 University of Southampton Southampton SO 17 1B J UK

Through the widespread implementation of next-generation sequencing （NGS）, analyses of the whole genome （the entire DNA content） and the whole transcriptome （the genes being expressed） are becoming commonplace. NGS enables the analysis of a vast amount of previously unattainable genetic information. Despite this potential, NGS has yet to be widely imple- mented in genetic studies of biological invasions. The study of the genomic causes and consequences of biological invasions al- lows a deeper understanding of the molecular mechanisms underpinning the invasion process. In this review, we present a brief introduction to NGS followed by a synthesis of current research in the genomics and transcriptomics of adaptation and coloniza- tion. We then highlight research opportunities in the field, including：（1） assembling genomes and transcriptomes of non-model organisms, （2） identifying genomic regions and candidate genes underlying evolutionary processes, and （3） studying the adaptive role of gene expression variation. In particular, because introduced species face a broad range of physiological and biotic chal- lenges when colonizing novel and variable environments, transcriptomics will enable the study of gene regulatory pathways that may be responsible for acclimation or adaptation. To conclude, we identify a number of research approaches that will aid our fu- ture understanding of biological invasions

关键词： Exotic species Genomics Genotype-environment interactions Invasive species Invasion genetics Invasion route Non-indigenous species Non-native species

Projection Preconditioner for Solving the Implicit Immersed Boundary Equations

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Numerical Mathematics(Theory,Methods and Applications) 2014年第4期7卷 473-498页

作者： Qinghai Zhang Robert D.guy Bobby Philip Department of Mathematics University of UtahSalt Lake CityUT 84112USA Department ofMathematics University of California DavisDavisCA 95616USA Oak Ridge National Laboratory Oak RidgeTN 37831USA

This paper presents a method for solving the linear semi-implicit immersed boundary equations which avoids the severe time step restriction presented by explicit-time *** Lagrangian variables are eliminated via a Schur complement to form a purely Eulerian saddle point system,which is preconditioned by a projection operator and then solved by a Krylov subspace *** the viewpoint of projection methods,we derive an ideal preconditioner for the saddle point problem and compare the efficiency of a number of simpler preconditioners that approximate this perfect *** low Reynolds number and high stiffness,one particular projection preconditioner yields an efficiency improvement of the explicit IB method by a factor around *** speed-ups over explicit-time method are achieved for Reynolds number below *** speedup increases as the Eulerian grid size and/or the Reynolds number are further reduced.

关键词： Fluid-structure interaction immersed boundary method projection method preconditioning