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COMPOUND ACTION POTENTIAL OF PERIPHERAL NERVE BY MES AND CES ABOUT DIFFERENCES OF TECHNICAL CHAKACTERISTICS

Chinese Journal of Biomedical Engineering(English Edition) 1999年第3期8卷 54-55页

作者： llu hongguang ZHOU Lin JIANG Dazong(Research Institute of Biomed. Eng, Xi’an Jiaotong Uni. Xi’an 710049, China)(Shannxi Normal University (now Japan x 630-8485, Nara University)

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Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor lluís Coll David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

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页岩气地质工程一体化产能优化研究

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地质论评 2024年第S1期70卷 339-341页

作者：蒋克成周刚刘胜昆仑数智科技有限责任公司智慧油田事业部北京100040

页岩气井的产能是地质、油藏、工程等方面众多参数的综合反映。页岩气开发过程中,产能的准确预测和优化对降本增效具有重大意义。然而,产能影响涉及方面广、因素多,常规方法进行的单因素分析拟合度较差,各影响因素相互关系难以确定。有... 详细信息

页岩气井的产能是地质、油藏、工程等方面众多参数的综合反映。页岩气开发过程中,产能的准确预测和优化对降本增效具有重大意义。然而,产能影响涉及方面广、因素多,常规方法进行的单因素分析拟合度较差,各影响因素相互关系难以确定。有些研究人员采用多属性进行非线性拟合的方法也很难尽如人意,而且这类方法一般都只是对已经施工的井进行产量预测,无法开展产能评价.

关键词：页岩气地质工程一体化产能优化机器学习

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凝汽器布管优化及其节能改造

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东方汽轮机 2024年第1期 20-24页

作者：陶友军黄文兵刘洋刘宏波德阳东汽电站机械制造有限公司四川绵竹618200 西南石油大学四川成都610500

CFD技术的发展为凝汽器流场仿真优化提供了更为可行和便捷的方法。为设计更为合理高效的凝汽器布管方式,文章通过采用商业CFD软件和二维多孔介质模型对凝汽器壳侧布管进行流动仿真,得出管束分析截面的速度场、压力场、不凝结气体浓度的... 详细信息

CFD技术的发展为凝汽器流场仿真优化提供了更为可行和便捷的方法。为设计更为合理高效的凝汽器布管方式,文章通过采用商业CFD软件和二维多孔介质模型对凝汽器壳侧布管进行流动仿真,得出管束分析截面的速度场、压力场、不凝结气体浓度的仿真结果,指导布管优化。结合凝汽器实际改造项目性能试验结果,验证了基于FLUENT二维多孔介质模型对凝汽器进行仿真优化是可行、可靠的。根据仿真结果指导进行的凝汽器改造的实际节能效果显著。

关键词：凝汽器布管优化多孔介质模型节能改造

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Switching between emission and photochemistry in an aggregation-induced emitter with extended conjugation

Aggregate

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Aggregate 2022年第3期3卷 98-99页

作者： lluís Blancafort Institut de Química Computacional i Catàlisi Department of ChemistryUniversitat de GironaC/M.A.Capmany 69Girona 17003Spain

Light emission and photochemistry can be related in different ways:photochemical reactions can lead to dual emission,[1]such as in excited state intramolecular proton transfer,but they often lead to emission *** such quenching process is the Mallory reaction undergone by molecules that contain Z-1,2-diphenyl ethylene(DPE)units.[2]It is a photochemical oxidative coupling(stepwise cyclization and hydrogen elimination)that converts DPE derivatives into phenanthrenes.

关键词： aggregation-induced emission mallory reaction

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2014铝合金表面Ni-P/金刚石复合镀层的制备和性能

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材料保护 2024年第9期57卷 148-153,160页

作者：宫璇刘家辰崔彦李强中国石油集团测井有限公司陕西西安710000 中国石油天然气股份有限公司长庆油田分公司陕西西安710000

为了提高铝合金表面的耐磨能力,采用电沉积法在2014铝合金表面制备了Ni-P/金刚石复合镀层,利用波长色散X射线荧光光谱分析以及扫描电子显微镜、维氏硬度仪、电化学工作站、摩擦磨损试验机等仪器设备研究了镀层中不同金刚石颗粒含量对镀... 详细信息

为了提高铝合金表面的耐磨能力,采用电沉积法在2014铝合金表面制备了Ni-P/金刚石复合镀层,利用波长色散X射线荧光光谱分析以及扫描电子显微镜、维氏硬度仪、电化学工作站、摩擦磨损试验机等仪器设备研究了镀层中不同金刚石颗粒含量对镀层的元素组成、表面形貌、显微硬度、腐蚀性能和耐磨性的影响。结果表明,随着镀液中金刚石颗粒添加量从0增加至1.0 g/L,镀层的腐蚀电流密度降低,腐蚀电位升高,显微维氏硬度从526 HV_(0.5)升高至786 HV_(0.5);当金刚石颗粒添加量为1.0 g/L时,镀层的磨损率最低。随着金刚石含量的增加,镀层的磨损机理由疲劳磨损转变为疲劳磨损与黏着磨损的相互作用再转变为黏着磨损。

关键词：电沉积 Ni-P/金刚石复合镀层耐磨性耐腐蚀性

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Sessile oak forest plant community changes on the NE Iberian Peninsula over recent decades

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Journal of Plant Ecology 2019年第5期12卷 894-906页

作者： Jordi Bou lluís Vilar LAGP-Flora and Vegetation Institute of the EnvironmentUniversity of GironaGironaCataloniaSpain

Aims Our aims were 3-fold:(i)to determine whether global change has altered the composition and structure of the plant community found in the sessile oak forests on the NE Iberian Peninsula over the last decades,(ii)to establish whether the decline in forest exploitation activities that has taken place since the mid-20th century has had any effect on the forests and(iii)to ascertain whether there is any evidence of impact from climate *** We assess changes in the plant community by comparing a cur-rent survey of sessile oak forest with a historical data set obtained from previous regional studies dating from 1962 to *** ana-lyse the regional changes in the community in terms of biodiversity variables,species composition and plant ***,plants traits such as plant life forms and chorological groups are used to discern any effects from land-use changes and climate warming on the plant *** Findingsthere has been a loss of diversity in the community and,in the hottest region,there is also a loss of species *** composition of the community suggests that,although significant changes have taken place over recent decades,these changes differ between regions as a result of the low impact global change has had in the western *** instance,while the tree canopy cover in the western sessile oak forests remains stable,the eastern sessile oak forests are still recovering from the former exploitation that led to a loss of their rich and abundant herbaceous *** fact,the recovery process in the catalan Pre-coastal Range has constituted an increase in the Euro-Siberian plants typical to this ***,in the eastern forests,there is evidence that climate warming has impacted the thermophilization of the sessile oak forests found on the coastal Range.

关键词： global change community ecology Quercus petraea forest ecology

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H?LDER CONTINUITY FOR THE PARABOLIC ANDERSON MODEL WITH SPACE-TIME HOMOGENEOUS GAUSSIAN NOISE

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Acta Mathematica Scientia 2019年第3期39卷 717-730页

作者： Raluca M BALAN lluís QUER-SARDANYONS Jian SONG Department of Mathematics and Statistics University of Ottawa Departament de Matemàtiques Universitat Autònoma de Barcelona School of Mathematics Shandong University

In this article, we consider the Parabolic Anderson Model with constant initial condition, driven by a space-time homogeneous Gaussian noise, with general covariance function in time and spatial spectral measure satisfying Dalang’s condition. First, we prove that the solution(in the Skorohod sense) exists and is continuous in L^p(?). Then, we show that the solution has a modification whose sample paths are H?lder continuous in space and time,under the minimal condition on the spatial spectral measure of the noise(which is the same as the condition encountered in the case of the white noise in time). This improves similar results which were obtained in [6, 10] under more restrictive conditions, and with sub-optimal exponents for H?lder continuity.

关键词： Gaussian noise stochastic partial differential equations Malliavin calculus

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Nonnegative matrix factorization and its applications in pattern recognition

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Chinese Science Bulletin 2006年第1期51卷 7-18页

作者： llu Weixiang ZHENG Nanning YOU Qubo Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University Xi'an 710049 China

Matrix factorization is an effective tool for large-scale data processing and analysis. Non- negative matrix factorization (NMF) method, which decomposes the nonnegative matrix into two non- negative factor matrices, provides a new way for ma- trix factorization. NMF is significant in intelligent information processing and pattern recognition. This paper firstly introduces the basic idea of NMF and some new relevant methods. Then we discuss the loss functions and relevant algorithms of NMF in the framework of probabilistic models based on our re- searches, and the relationship between NMF and information processing of perceptual process. Finally, we make use of NMF to deal with some practical questions of pattern recognition and point out some open problems for NMF.

关键词：特征抽取 NMF 模式识别计算机

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THREE-DIMENSIONAL COUPLED IMPELLER-VOLUTE SIMULATION OF FLOW IN CENTRIFUGAL PUMP AND PERFORMANCE PREDICTION

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 59-62页

作者： ZHAO Binjuan YUAN Shouqi llu Houlin TAN Minggao School of Energy and Power Engineering Jiangsu University Zhenjiang 212013 China Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

A three-dimensional turbulent flow through an entire centrifugal pump is simulated using k-ε turbulence model modified by rotation and curvature, SIMPLEC method and body-fitted coordinate. The velocity and pressure fields are obtained for the pump under various working conditions, which is used to predict the head and hydraulic efficiency of the pump, and the results correspond well with the measured values. The calculation results indicate that the pressure is higher on the pressure side than that on the suction side of the blade; The relative velocity on the suction side gradually decreases from the impeller inlet to the outlet, while increases on the pressure side, it finally results in the lower relative velocity on the suction side and the higher one on the pressure side at the impeller outlet; The impeller flow field is asymmetric, i.e. the velocity and pressure fields arc totally different among all channels in the impeller; In the volute, the static pressure gradually increases with the flow route, and a large pressure gratitude occurs in the tongue; Secondary flow exists in the rear part of the spiral.

关键词： Centrifugal pump Numerical simulation Performance prediction Secondary flow

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