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Short term effects of fire intensity and fire regime on vegetation dynamic in a tropical humid savanna(Lamto,central Cote d’Ivoire)

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natural Science 2012年第12期4卷 1056-1064页

作者： A.B.n’Dri j.Gignoux A.Dembele S.Konate Unit of Training and Research in natural Science Center for Research in EcologyLamto Station of EcologyNangui Abrogoua UniversityAbidjanCote d’Ivoire BIOEMCO(Laboratoire de BIOgeochimie et Ecologie des Milieux COntinentaux)Laboratory UMR-7618University Pierre et Marie CurieCNRSENSParisFrance

We tested the effects of different fire regimes (with different fire date and fuel load) on grass growth, tree debarking and topkill in a Guinea savanna of West Africa. Different fire intensities were simulated on two plots of 3.72 ha each, delimited in two shrubby savanna of the Lamto reserve (C?te d’Ivoire). Two fire regimes were applied, the mid-season fire (january) and the late fire (April). Two fuel levels (single: C1 and double: C2) have been used. For each fire regime, fire intensity was determined. It increases with the fuel quantity (1259 ± 356 kW·m–1 and 3380 ± 1472 kW·m–1 respectively for C1 and C2). The regrowth speed of grasses is also dependent on the fuel quantity (grasses). It increases with it and is higher after the mid-season fire than the late fire. The average intensity of the mid-season fire (2966 ± 2233 kW·m–1) is not significantly different from that of the late fire (1673 ± 1124 kW·m–1). Damages or debarking caused by fire on adult trees were recorded and are linked to fire intensity. Those damages appear to initiate the external cavity observed on trees, known to be detrimental to tree trunk mechanical resistance. They generally affect adult trees of Crossopteryx febrifuga species which is also the most commonly hollowed species. Mid-season fire remains the recommanded fire regime because it insures a faster regrowth of grasses which leads to the maintenance of equilibrium between grasses and trees.

关键词： Fire Intensity Fuel Load Fire Regime Savanna Vegetation

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Generalizing plant–water relations to landscapes

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journal of Plant Ecology 2011年第1期4卷 101-113页

作者： R.H.Waring j.j.Landsberg College of Forestry Oregon State UniversityCorvallisOR 97331USA Withycombe Church LaneMt WilsonNSW 2786Australia

Aims Changing climate and land use patterns make it increasingly important that the hydrology of catchments and ecosystems can be reliably *** aim of this paper is to identify the biophysical factors that determine the rates of water vapor loss from different types of vegetation,and to seek,from an array of currently available satelliteborne sensors,those that might be used to initialize and drive landscape-level hydrologic *** Findings Spatial variation in the mean heights,crowd widths,and leaf area indices(LAI)of plant communities are important structural variables that affect the hydrology of *** stomatal conductance(G)imposes physiological limitation on transpiration by *** maximum value of G(Gmax)is closely linked to canopy photosynthetic capacity,which can be estimated via remote sensing of foliar chlorophyll or nitrogen *** be modeled as a nonlinear multipliable function of:(i)leaf–air vapor pressure deficit,(ii)water potential gradient between soil and leaves,(iii)photosynthetically active radiation absorbed by the canopy,(iv)plant nutrition,(v)temperature and(vi)the CO_(2) concentration of the *** surveys with Light Detection and Ranging(LiDAR)and interferometric RADAR,along with high-resolution spectral coverage in the visible,near-infrared,and thermal infrared bands,provide,along with meteorological data gathered from weather satellites,the kind of information required to model seasonal and interannual variation in transpiration and evaporation from landscapes with diverse and dynamic vegetation.

关键词： canopy stomatal conductance plant water relations process-based models remote sensing

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Seladelpar治疗原发性胆汁性胆管炎患者的临床研究

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中国临床药理学杂志 2024年第8期40卷 1207-1207页

作者： HIRSCHFIELD G M BOWLUS C L MAYO M j 孟海峰

本研究是一项为期12个月随机、双盲、安慰剂对照的Ⅲ期临床试验,将对熊去氧胆酸反应不足或有不可接受药物不良反应史的原发性胆汁性胆管炎患者按照2:1的比例随机分为试验组(口服10mg·d^(-1)seladelpar)与安慰剂组(口服安慰剂)。主要治... 详细信息

本研究是一项为期12个月随机、双盲、安慰剂对照的Ⅲ期临床试验,将对熊去氧胆酸反应不足或有不可接受药物不良反应史的原发性胆汁性胆管炎患者按照2:1的比例随机分为试验组(口服10mg·d^(-1)seladelpar)与安慰剂组(口服安慰剂)。主要治疗终点是生化反应,其定义为12个月时碱性磷酸酶水平低于正常范围上限的1.67倍,比基线下降15%或更多,总胆红素水平正常。次要治疗终点是12个月时碱性磷酸酶水平的正常化,以及基线评分至少为4(表示中度至重度瘙痒)的患者从基线到6个月瘙痒数值评定量表评分的变化[范围为0(无瘙痒)到10(可想象的最严重瘙痒)]。

关键词：安慰剂对照 Ⅲ期临床试验原发性胆汁性胆管炎熊去氧胆酸碱性磷酸酶药物不良反应总胆红素水平治疗终点

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Managing advertising campaigns-an approximate planning approach

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Frontiers of Computer Science 2012年第2期6卷 209-229页

作者： SertanGIRGIn jérémieMARY PhilippePREUX OliviernICOL Team—projectSequeL INRIALilleNordEuropeVilleneuved’Ascq59650France LIFLUMRCnRS Universit6deLilleVilleneuved’Ascq59650France

We consider the problem of displaying commer- cial advertisements on web pages, in the ＂cost per click＂ model. The advertisement server has to learn the appeal of each type of visitor for the different advertisements in order to maximize the profit. Advertisements have constraints such as a certain number of clicks to draw, as well as a lifetime. This problem is thus inherently dynamic, and intimately com- bines combinatorial and statistical issues. To set the stage, it is also noteworthy that we deal with very rare events of in- terest, since the base probability of one click is in the or- der of 10-4. Different approaches may be thought of, rang- ing from computationally demanding ones （use of Markov decision processes, or stochastic programming） to very fast ones. We introduce nOSEED, an adaptive policy learning al- gorithm based on a combination of linear programming and multi-arm bandits. We also propose a way to evaluate the extent to which we have to handle the constraints （which is directly related to the computation cost）. We investigate the performance of our system through simulations on a realistic model designed with an important commercial web actor.

关键词： advertisement selection web sites optimiza-tion non-stationary setting linear programming multi-armbandit click-through rate (CTR) estimation exploration-exploitation trade-off

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InFORMATIOn SHARInG AnD STRATEGIC SIGnALInG In SUPPLY CHAInS

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journal of Systems Science and Systems Engineering 2009年第2期18卷 129-158页

作者： Robert j.KAUFFMAn Hamid MOHTADI W.P.Carey School of Business and School of Computing and InformaticsArizona State University TempeAZ85287 USA Department of Economics University of WisconsinMilwaukeeWI53201 and Credit Risk AssessmentUSBankMinneapolisMN55402USA

Information sharing in procurement occurs in rich and varied industry contexts in which managerial decisions are made and organizational strategy is formulated. We explore how information sharing ought to work in procurement contexts that involve investments in inter-organizational information systems （IOS） and collaborative planning, forecasting and replenishment （CPFR） practices. How and under what circumstances does a firm that plays the role of a supply chain buyer decide to share information on key variables, such as point-of-sale consumer demand data with its supplier, up the supply chain？ This is a key issue that crosses the boundary between supply chain management and information systems （IS） management. The answers that we provide are based on our use of a game-theoretic signaling model of buyer and supplier strategy in the presence of uncertainties about final consumer demand. We also explore the connection between operational costs that are associated with the firm＇s information sharing and information withholding strategies. Our results provide normative guidance to supply chain buyers about how to interpret different demand uncertainty scenarios to improve their decisions and generate high value. From the IS management perspective, we show the impacts on the firm of different information sharing approaches that are made possible by present day technologies.

关键词： Anticipated over-supply collaborative planning forecasting and replenishment (CPFR) demand forecasting economic analysis information sharing information systems (IS) signaling supply chain management

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涡流探头线圈阻抗分量标准化的推算

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无损检测 1992年第4期14卷 115-120页

作者： n.T.Hajian j.Blitz 傅国英

推算的目的是使具一定长度空芯线圈的平面式探头在涡流探伤仪上的指示值标准化,此外,还讨论了在使用铁磁芯线圈及其检测铁磁性金属时所遇到的问题。

关键词：涡流探头线圈阻抗分量

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Power-Sharing Enhancement Using Harmonized Membership Fuzzy Logic Droop Control Based Micro-Grid

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Intelligent Automation & Soft Computing 2023年第5期36卷 1395-1415页

作者： W.j.Praiselin j.Belwin Edward School of Electrical Engineering Vellore Institute of TechnologyVellore632014TamilnaduIndia

The contribution of Renewable Energy Resources(RER)in the process of power generation is signiﬁcantly high in the recent days since it paves the way for overcoming the issues like serious energy crisis and natural *** paper deals with the renewable energy based micro-grid as it is regarded as the apt solution for integrating the RER with the electrical *** theﬁxed droop coefﬁcients in conventional droop control approaches have caused various limitations like low power-sharing and sudden drops of grid voltage in the Direct Current(DC)side,the Harmonized Membership Fuzzy Logic(MFL)droop control is employed in this present *** proposed droop control for the hybrid PV-wind-battery system with MFL assists in achieving proper power-sharing and minimizing Total Harmonic Distortion(THD)in the emer-gency *** eradicates the deviations in voltage and frequency with itsﬂexible and robust *** THD is reduced and attains the value of 3.1%compared to the traditional droop *** simulation results of harmo-nized MFL droop control are analogized with the conventional approaches to vali-date the performance of the proposed *** addition,the experimental results provided by the Field Programmable Gate Array(FPGA)based laboratory setup built using a solar photovoltaic(PV)and wind Permanent Magnet Synchro-nous Generator(PMSG)reafﬁrms the design.

关键词： Micro-grid harmonized droop control fuzzy power-sharing total harmonic distortion

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Implications of the EU’s Inclusion of Maritime Transport in the Emissions Trading System for Shipping Companies

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Engineering 2021年第5期7卷 554-557页

作者： Shuaian Wang Lu Zhen Harilaos n.Psaraftis Ran Yan Department of Logistics and Maritime Studies The Hong Kong Polytechnic UniversityHong Kong 999077China School of Management Shanghai UniversityShanghai 200444China Department of Management Engineering Technical University of DenmarkLyngby DK-2800Denmark

*** Maritime transport is the backbone of international *** amount of total international maritime trade in million tonnes loaded was 8408 in 2012 and had increased to 11076 by 2019,for an average annual increase of 3.12%.In early 2020,the world fleet contained 98140 ships of 100 gross tonnes and above with 2.06 million dead weight tonnage of capacity[1].The greenhouse gas(GHG)emissions from shipping activities are not *** to the fourth GHG study commissioned by the International Maritime Organization(IMO),in 2018,global shipping emitted a total of 1056 million tonnes of carbon dioxide(CO_(2)),accounting for around 2.89%of global anthropogenic CO_(2) emissions[2].Due to the international nature of shipping,efforts to control CO_(2) emissions from ships are absent from the Kyoto Protocol and the Paris *** an attempt to phase out carbon emissions from shipping entirely,the IMO formulated a strategy to cut the total annual GHG emissions from shipping by at least 50%from their 2008 levels by 2050[3];however,no mandatory rules have been promulgated since the release of this strategy.

关键词： backbone shipping entirely

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Gifted Education in Hong Kong:A School-Based Support Program Catering to Learner Diversity

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ECnU Review of Education 2020年第4期3卷 632-658页

作者： Ruby S.H.Cheung Anna n.n.Hui Alan C.K.Cheung The Chinese University of Hong Kong City University of Hong Kong Department of Educational Administration and Policy Jockey Club“Giftedness into Flourishing Talents”ProjectFaculty of EducationThe Chinese University of Hong KongHong Kong SARChina

Purpose:This study explores the contributions and effectiveness of the jockey Club“Giftedness into Flourishing Talents”Project(Project GIFT)in supporting learner diversity in gifted education,including meeting the educational and psychological needs of highly capable and gifted students in Hong ***/Approach/Methods:This study investigates the effectiveness of Project GIFT in supporting the development of diversity in learning in 20 project *** close cooperation with project schools,Project GIFT comprised six developmental areas:school development,curriculum development,teachers’professional development,parent empowerment,student development,and financial *** further assess the usefulness of the school-based support provided by Project GIFT,this study examines the implementation of school-based gifted education in two project schools based on the aforementioned *** program in gifted education that intervened at both Level 1(whole class)and Level 2(pullout)of the three-tiered policy stipulated by the Hong Kong Education *** of the few gifted education programs implemented in Asia,Project GIFT focused on six key components to specifically support high-ability and gifted students with diverse educational and affective *** study shows that Project GIFT significantly enhanced diversity in learning,its collaboration with two key schools resulting in the successful enhancement of school development,professional development,curriculum development,student development,parent empowerment,and financial ***/Value:The article fills the research gap by examining the effectiveness of a schoolbased gifted education program focused on enriching and differentiating curricula for different regular and pull-out *** doing so,this article attests to the success of the program in addressing the educational and psychosocial needs of gifted students at local schools in Hong Kong.

关键词： Enriched and differentiated curricula gifted education giftedness learner diversity school-based curriculum talent search and development

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Deposition of litter and nutrients in leaves and twigs in different plant communities of northeastern Mexico

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journal of Forestry Research 2018年第5期29卷 1307-1314页

作者： Humberto González-Rodríguez Roque Gonzalo Ramírez-Lozano Israel Cantú-Silva Marco Vinicio Gómez-Meza Eduardo Estrada-Castillón josé Ramón Arévalo Facultad de Ciencias Forestales Universidad Autdnoma deNuevo Ledn Carr. Nac. No 85 km 145 67700 LinaresNuevo Ledn Mexico Facultad de Ciencias Bioldgicas Universidad Autdnoma deNuevo Ledn Ave. Universidad S/N Cd. Universitaria66451 San Nicolfis de los Garza Nuevo Ledn Mexico Facultad de Economla Universidad Autdnoma de NuevoLedn Monterrey Nuevo Ledn Mexico Departamento de Botanica Ecologiay Fisiologfa Vegetal Facultad de Ciencias Universidad de La LagunaCanary Islands Spain

Studies on litterfall and decomposition provide estimations of decomposition rates of different *** is key information to understanding ecosystem dynamics and changes in a scenario of global *** objective of this research was to assess litterfall production,the potential deposition of macro and micronutrients through leaf and twig fall as well as macronutrient—use efficiency in three forest ecosystems at different altitudes： a pine forest mixed with deciduous species（S1）; a Quercus ***（S2）; and,a Tamaulipan thornscrub forest（S3）.Total annual litterfall deposition was 594,742 and 533 g m^（-2） for S1,S2 and *** litter was higher （68%） than twigs（18%）,reproductive structures（8%） or miscellaneous material（6%）.Micronutrient leaf deposition was higher for Fe followed by Mn,Zn and *** leaf deposition was higher for Ca followed by K,Mg and *** though P deposition in leaves and twigs was lower than other macronutrients,its nutrient use efficiency was higher than Ca,Mg or *** and species composition determine litter and nutrient deposition,with higher values at mid-altitudes（550 m）.Altitude is an important factor to consider when analyzing litter production as well as nutrient deposition as shown in this *** production and nutrient deposition are expected to change in a scenario of global warming.

关键词： Deciduous species Litter deposition Leaf/twig litter nutrients Pine forest Tamaulipan thornscrub

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