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Comparing growth and fine root distribution in monocultures and mixed plantations of hybrid poplar and spruce

Journal of Forestry Research 2013年第2期24卷 247-254页

作者： Lahcen Benomar Annie DesRochers guy R. Larocque Chaire industrielle CRSNG-UQAT-UQAm en aménagement forestier durable. Université du Québec en Abitibi-Témiscamingue Natural Resources Canada Laurentian Forestry Centre

Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones, P. balsamifera x trichocarpa （PBT） and P. maximowiczii x balsamifera （PmB）, one improved family of Norway spruce （Picea glauca （PA）） and one improved family of white spruce （Picea abies （PG）） growing under different spacings in monocultures and mixed plots. The plantations were established in 2003 in Abitibi-Témiscamingue, Quebec, Canada, in a split plot design with spacing as the whole plot factor （1 × 1 m, 3 × 3 m and 5 × 5 m） and mixture treatments as subplot factor （pure： PBT, PmB, PA and PG, and 1：1 mixture PBT：PA, PBT：PG, PmB：PA and PmB：PG）. Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones, but not for the 5 × 5 m spacing because of the relatively young age of the plantations. Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m, while their height growth increased, resulting in similar aboveground biomass per tree across treatments. Because of the large size differences between spruces and poplars, aboveground biomass in the mixed plantings was generally less than that in pure poplar plots. Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PmB was greater in mixed plots than in monocultures, while leaf nitrogen concentration of clone PBT was similar among mixture treatments. Because of its faster growth rate and greater soil resources demands, clone PmB was the only one showing an increase in leaf N with increased spacing between trees. Fine roots density was greater for both hybrid poplars than spruces. The vertical distribution of fine roots was insensitive to mixture treatment.

关键词： Picea glauca Populus balsamifera × trichocarpa P. maximowiczii × balsamifera mixed-species monoculture spacing fine root

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Characterisation of likelihood of gas hydrates occurrence in the South China Sea based on Bonferroni mean-based TOPSIS and fuzzy set theory

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Geoscience Frontiers 2023年第2期14卷 59-70页

作者： Pierre guy Atangana Njock Shui-Long Shen Annan Zhou mOE Key Laboratory of Intelligent manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityGuangdong 515063China Discipline of Civil and Infrastructure Engineering School of EngineeringRoyal Melbourne Institute of TechnologyVictoria 3001Australia

The efficiency of gas hydrate production depends on the success of gas exploration and occurrence *** existing evaluation models are generally univariate and only applicable to certain geological *** study presents a holistic approach to evaluate the likelihood of gas hydrate occurrence by supplying an index for mapping gas hydrate levels with *** approach integrates a generalised TOPSIS method with the fuzzy set *** expedition of gas hydrate conducted in the Shenhu area of the South China Sea was adopted as a case study to assess the reliability of the proposed *** a multivariate model,the proposed approach enables the capture of non-linearity associated with gas hydrates in its *** magnitude of the strength of the influential factor varies substantially from one site to another across the Shenhu *** results also show that no site achieves the highest likelihood‘Level V’.These results are consistent with the gas saturation values obtained using Archie’s *** example,at SH4 and SH7,the values of the likelihood index are the highest between 170–185 m and 150–165 m,respectively,and the observed saturation at these locations varies from 20%(SH4)to 43%(SH7).The proposed likelihood index yields a prominent ability to quantify the level of occurrence of gas hydrates with depth at different *** appears to be an efficient multicriteria system bound to improve the management of the gas production trial stage.

关键词： Gas hydrates South China Sea Geologic controls Occurrence characterization Energy resource

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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

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Rural transformation:Cherry growing on the Guanzhong Plain, China and the Adelaide Hills, South Australia

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Journal of Geographical Sciences 2019年第5期29卷 675-701页

作者： guy m.ROBINSON 宋冰洁 Department of Geography Environment and Population University of Adelaide School of Geography and Tourism Shaanxi Normal University

This paper echoes a tradition in agricultural geography by focusing on a single crop:cherries. It illustrates how developments associated with globalisation and growing urban markets are re-shaping rural areas. The interplay between global and local is investigated in two different contexts. A Chinese example reflects transformations affecting the countryside following national economic reforms. Focusing on the hinterland of Xi'an, capital of Shaanxi Province, it examines farmers' responses to the changing socio-political context and the rising size and wealth of the local market. Individual initiatives backed by government support have spawned localised concentrations of cherry growing and increased horticultural ***-based tourism is creating new relationships between farmers and consumers, with farms becoming more diversified and multifunctional. The second example is the Adelaide Hills, South Australia, where cherry growing is increasingly combined with direct sales to consumers and gastronomic tourism. The paper addresses contrasts and similarities between the two examples in the interplay between global and local, and a ‘multifunctional transition' in farming. Concluding remarks include reference to new economic links forged between China and Australia through relaxations on cherry imports to China and new patterns of Chinese foreign direct investment into Australian cherry production. A research agenda for future research is suggested.

关键词： cherries agriculture rural tourism globalisation multifunctional China Australia

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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

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Urban spatial development and land use in Beijing： Implications from London＇s experiences

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Journal of Geographical Sciences 2011年第1期21卷 49-64页

作者： TAN minghong guy m. Robinson LI Xiubin Institute of Geographic Science and Natural Resources Research CAS Beijing 100101 China Centre for Rural Health & Community Development University of South Australia 111 Nicolson Avenue Whyalla Norrie South Australia 5608 Australia

Beijing is facing a huge challenge to manage the growth of its built-up area whilst also retaining both productive arable land and land for conservation purposes in order to simultaneously realize the three aims of economic development,protecting arable land and generating environmental improvements. meanwhile,London,as a world city with more than 200 years of industrialization and urbanization,has accumulated rich theoretical and practical experiences for land use planning in a major urban area,such as the creation of Garden Cities,a designated Green Belt and New Towns. This paper firstly analyzes the main characteristics of the spatial distribution of the built-up area,arable land and conservation land in Beijing. Then,some of the key aspects of urban fringe planning in the London region are examined. Lastly,several implications from the experience of London are provided with respect to land-use planning for Beijing,concentrating on a re-appraisal of land-use functions around Beijing,measures to improve the green belt,the development of small towns to house rural-urban migrants and urban overspill,and effective implementation of land-use planning.

关键词： Beijing London land-use planning Green Belt New Towns

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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

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用脉冲半导体激光观察铷原子基态塞曼能级的相干共振

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光学学报 1992年第11期12卷 992-997页

作者：杨世琪 m.Tetu N.Cyr m.guy 华南师范大学物理系广州510631 加拿大拉瓦尔大学电机系光学和激光光电子中心

用半导体激光脉冲序列泵浦汽泡铷原子,观察其基态能级的△m=1和△m=2的塞曼(Zeeman)相干.利用直接调制激光二极管注入电流的增益开关技术,在波长780nm处产生约200ps的激光脉冲.对△m=1,用偏振光谱学方法检测;而对△m=2,则直接使用前向... 详细信息

用半导体激光脉冲序列泵浦汽泡铷原子,观察其基态能级的△m=1和△m=2的塞曼(Zeeman)相干.利用直接调制激光二极管注入电流的增益开关技术,在波长780nm处产生约200ps的激光脉冲.对△m=1,用偏振光谱学方法检测;而对△m=2,则直接使用前向散射光谱学方法检测.

关键词：脉冲激光塞曼效应激光技术铷

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Non-contact tensile viscoelastic characterization of microscale biological materials

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Acta mechanica Sinica 2018年第3期34卷 589-599页

作者： Yuhui Li Yuan Hong Guang-Kui Xu Shaobao Liu Qiang Shi Deding Tang Hui Yang guy m.Genin Tian Jian Lu Feng Xu The Key Laboratory of Biomedical Information Engineeringof ministry of Education School of Life Science and TechnologyXi'an Jiaotong UniversityXi'an 710049China Biomedical Engineering and Biomechanics Center(BEBC) Xi'an Jiaotong UniversityXi'an 710049China Intemational Center for Applied mechanics State Key Laboratory for Strength and Vibration of Mechanical StructuresXi'an Jiaotong UniversityXi'an 710049China School of Life Sciences Northwestern Polytechnical UniversityXi'an 710072China The NSF Science and Technology Center for Engineering mechano-Biology Washington UniversitySaint LouisMO 63130.USA

many structures and materials in nature and physiology have important ＂meso-scale＂ structures at the micron lengthscale whose tensile responses have proven difficult to characterize mechanically. Although techniques such as atomic force microscopy and micro- and nano-identation are mature for compression and indentation testing at the nano-scale, and standard uniaxial and shear rheometry techniques exist for the macroscale, few techniques are applicable for tensile-testing at the micrometre-scale, leaving a gap in our understanding of hierarchical biomaterials. Here, we present a novel magnetic mechanical testing （mmT） system that enables viscoelastic tensile testing at this critical length scale. The mmT system applies non-contact loading, avoiding gripping and surface interaction effects. We demonstrate application of the mmT system to the first analyses of the pure tensile responses of several native and engineered tissue systems at the mesoscale, showing the broad potential of the system for exploring micro- and meso-scale analysis of structured and hierarchical biological systems.

关键词： mechanical testing Hierarchical biomaterials Non-contact actuation microscale analysis

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Canadian children’s and youth’s adherence to the 24-h movement guidelines during the COVID-19 pandemic: A decision tree analysis

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Journal of Sport and Health Science 2020年第4期9卷 313-321页

作者： michelle D.Guerrero Leigh m.Vanderloo Ryan E.Rhodes guy Faulkner Sarah A.moore mark S.Tremblay Children’s Hospital of Eastern Ontario Research Institute OttawaON K1H 8L1Canada ParticipACTION TorontoON M5S 1M2Canada Child Health and Evaluative Sciences Hospital for Sick ChildrenTorontoON M5G 0A4Canada Behavioral medicine Laboratory School of Exercise SciencePhysical and Health EducationUniversity of VictoriaVictoriaBC V8W 2Y2Canada School of Kinesiology University of British ColumbiaVancouverBC V6T 1Z1Canada Department of Therapeutic Recreation Faculty of ChildFamilyand Community StudiesDouglas CollegeCoquitlamBC V3B 7X3Canada School of Health and Human Performance Dalhousie UniversityHalifaxNS B3H 4R2Canada Department of Pediatrics University of OttawaOttawaON K1H 8L1Canada

Purpose:The purpose of this study was to use decision tree modeling to generate profiles of children and youth who were more and less likely to meet the Canadian 24-h movement guidelines during the coronavirus disease-2019(COVID-19)***:Data for this study were from a nationally representative sample of 1472 Canadian parents(meanage=45.12,SD=7.55)of children(511 years old)or youth(1217 years old).Data were collected in April 2020 via an online *** items assessed demographic,behavioral,social,micro-environmental,and macro-environmental *** decision trees of adherence and non-adherence to all movement recommendations combined and each individual movement recommendation(physical activity(PA),screen time,and sleep)were ***:Results revealed specific combinations of adherence and non-adherence *** associated with adherence to the recommendation(s)included high parental perceived capability to restrict screen time,annual household income ofCAD 100,000,increases in children’s and youth’s outdoor PA/sport since the COVID-19 outbreak began,being a boy,having parents younger than 43 years old,and small increases in children’s and youth’s sleep duration since the COVID-19 outbreak *** associated with non-adherence to the recommendation(s)included low parental perceived capability to restrict screen time,youth aged 1217 years,decreases in children’s and youth’s outdoor PA/sport since the COVID-19 outbreak began,primary residences located in all provinces except Quebec,low parental perceived capability to support children’s and youth’s sleep and PA,and annual household income ofCAD 99,***:Our results show that specific characteristics interact to contribute to(non)adherence to the movement behavior *** highlight the importance of targeting parents’perceived capability for the promotion of children’s and youth’s movement behaviors during challengin

关键词： Decision tree analysis Parental perceived capability Physical activity Screen time Sleep

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