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菌 糠 资 源 化 技 术  [PDF]
邹德勋,潘斯亮,黄 芳,汪群慧
北方园艺 , 2010, DOI: 10.11937/bfyy.201019072
Abstract:
美国社区创客教育的载体  [PDF]
李卢一,郑燕林
开放教育研究 , 2015,
Abstract: 美国推进全民创客行动的进程中,非常重视社区创客空间的建设,并积极动员全美各地区、各社区重视将创客行动纳入区域与社区的发展计划,众多社区创客空间明确提出自身所担负的教育责任。基于对美国若干社区创客空间建设目标与运行方式的分析,本文探析了作为社区创客教育主要载体的创客空间的发展动力、功用与应用。研究发现,技术与社会的发展是美国社区创客空间发展的根本动力,全美创客行动的深化实践则是美国社区创客空间发展的基本依托。在功用维度,美国社区创客空间具有培养社区成员创造创新能力、提升社区成员创业就业技能的教育功用,同时又具有创生就业创业机会、促进社区经济发展的经济功用;在应用维度,美国社区创客空间主要通过精心规划功能区支持多样化创客活动、采用适当的运行形式、多途径开展创客教育、多方位促进创客空间高效利用等实现并优化空间的应用。
图书馆创客空间建设研究  [PDF]
陶蕾
图书情报工作 , 2013,
Abstract: ?从创客空间的概念、兴起背景、成功案例出发,分析创客空间与图书馆的关系,探讨构建创客空间的要素和步骤。图书馆为创客空间提供孕育发展的平台,创客空间赋予图书馆服务“支持学习”的新内容,为未来图书馆转型提供了切入点。
甲板采用Kevlar的高速客艇  [PDF]
复合材料学报 , 1988,
Abstract: 日本IHI工艺公司完成了甲板等处采用Kevlar混杂铺层的双体型高速客艇,规定于1987年12月18日于印度尼西亚交货。该双体型高速客艇系日本航空与印尼企业合资在雅加达以北岛上建设的宾馆中作迎送客人之用,向雅马哈发动机公司和IHI工艺公司各订购一条,雅马哈的那一条已在当地就航。船名为“KEPEKEPE”,是天使鱼这种热带鱼的印尼叫法。
美国高校实施创客教育的路径分析  [PDF]
郑燕林
开放教育研究 , 2015,
Abstract: 近年来,随着全美创客行动(MakerMovement)的快速发展,美国越来越多的高校开始将创客教育(MakerEducation)作为培养学生创造与创新能力以及创业就业能力的重要途径。创客教育的核心是支持学生开展基于创造的学习,而基于创造的学习的关键是对学生学习主体性、实践性、深度参与性、连续性与完整性(学生往往需要完成从规划到设计再到开发制作产品的完整过程)的充分尊重。学生在基于创造的学习过程中需要主动发现、自主探究,在发现、分析与解决问题的过程中创生、验证、发展出自己的创想,在提升问题解决能力的同时又保持创造的激情与信心,这些是创造与创新能力的核心品质。基于对美国高校实施创客教育的具体举措与经验的梳理与总结,本文分析了美国高校开展创客教育的基本路径:在意识层面积极响应全美创客行动,充分重视创客教育在高等教育中的价值,这是实施创客教育的起点与目标指向;在规划层面注重对学校开展创客教育的整体设计,充分关注与社区创客教育的联动,这是实施创客教育的重要前提;在实践层面着力打造优质的创客空间提供创客教育环境,灵活选择适切的创客教育实施方式,这是创客教育得以真正实施的重要依托。
Selecting the optimal method to calculate daily global reference potential evaporation from CFSR reanalysis data
F. C. Sperna Weiland,C. Tisseuil,H. H. Dürr,M. Vrac
Hydrology and Earth System Sciences Discussions , 2011, DOI: 10.5194/hessd-8-7355-2011
Abstract: Potential evaporation (PET) is one of the main inputs of hydrological models. Yet, there is limited consensus on which PET equation is most applicable in hydrological climate impact assessments. In this study six different methods to derive global scale reference PET time series from CFSR reanalysis data are compared: Penman-Monteith, Priestley-Taylor and original and modified versions of the Hargreaves and Blaney-Criddle method. The calculated PET time series are (1) evaluated against global monthly Penman-Monteith PET time series calculated from CRU data and (2) tested on their usability for modeling of global discharge cycles. The lowest root mean squared differences and the least significant deviations (95 % significance level) between monthly CFSR derived PET time series and CRU derived PET were obtained for the cell specific modified Blaney-Criddle equation. However, results show that this modified form is likely to be unstable under changing climate conditions and less reliable for the calculation of daily time series. Although often recommended, the Penman-Monteith equation did not outperform the other methods. In arid regions (e.g., Sahara, central Australia, US deserts), the equation resulted in relatively low PET values and, consequently, led to relatively high discharge values for dry basins (e.g., Orange, Murray and Zambezi). Furthermore, the Penman-Monteith equation has a high data demand and the equation is sensitive to input data inaccuracy. Therefore, we preferred the modified form of the Hargreaves equation, which globally gave reference PET values comparable to CRU derived values. Although it is a relative efficient empirical equation, like Blaney-Criddle, the equation considers multiple spatial varying meteorological variables and consequently performs well for different climate conditions. In the modified form of the Hargreaves equation the multiplication factor is uniformly increased from 0.0023 to 0.0031 to overcome the global underestimation of CRU derived PET obtained with the original equation. It should be noted that the bias in PET is not linearly transferred to actual evapotranspiration and runoff, due to limited soil moisture availability and precipitation. The resulting gridded daily PET time series provide a new reference dataset that can be used for future hydrological impact assessments or, more specifically, for the statistical downscaling of daily PET derived from raw GCM data.
South American Climatology and Impacts of El Ni?o in NCEP’s CFSR Data  [PDF]
Timothy Paul Eichler,Ana C. Londo?o
Advances in Meteorology , 2013, DOI: 10.1155/2013/492630
Abstract: Understanding regional climate variability is necessary in order to assess the impacts of climate change. Until recently, the best methods for evaluating regional climate variability were via observation networks and coarse-gridded reanalysis datasets. However, the recent development of high-resolution reanalysis datasets offers an opportunity to better evaluate the climatologically diverse continent of South America. This study compares NCEP’s CFS reanalysis dataset with NCEP’s coarser-resolution reanalysis II dataset to determine if CFS reanalysis improves our ability to represent the regional climate of South America. Our results show several regional differences between the CFSR and Re2 data, especially in areas of large topographical gradients. A comparison with the University of Delaware and TRMM precipitation datasets lends credence to some of these differences, such as heavier precipitation associated with anomalous 925?hPa westerlies over northwestern Peru and Ecuador during El Ni?o. However, our results also stress that caution is advised when using reanalysis data to assess regional climate variability, especially in areas of large topographical gradient such as the Andes. Our results establish a baseline to better study climate change, especially given the release of IPCC AR5 model simulations. 1. Introduction Representing summer climatology in South America is complicated by the diversity of its topographical features. As noted by Garreaud et al. [1], the Andes act as a climatological barrier separating arid conditions to the west in the Peru-Bolivian Atacama Desert from wet conditions to the east in the Amazon Basin. The aridity in the Atacama Desert is related to the position of the southeastern Pacific subtropical high, which causes large-scale subsidence [2, 3]. The ability of the Andes to block tropospheric flow also results in a rain shadow in the Altiplano [4]. The precipitation that does occur in the area is confined mostly to austral summer (DJF) and is driven by diurnal convection and the westward transport of moisture from the interior of the continent [5–7]. With the recent implementation of high-resolution reanalysis datasets, it would be interesting to assess their ability to simulate South American climatology. This study compares the high-resolution CFSR data with coarse-grid reanalysis II (hereafter referred to as Re2) applied to South American climatology and interannual variability. The high-resolution reanalysis data will also allow us to detect features not seen in the coarse resolution data such as the climatological
利用cfsr资料分析近30年全球云量分布及变化  [PDF]
向华,张峰,江静,彭杰,张喜亮,张春艳
气象 , 2014, DOI: 10.7519/j.issn.1000-0526.2014.05.005
Abstract: 在利用modis卫星的云产品资料对cfsr(climateforecastsystemreanalysis)再分析资料云产品质量进行检验评估的基础上,采用cfsr资料对1979—2009年全球总云量及低、中、高云量的平均分布及其随纬度的变化进行了分析;用经验模态分解(emd)方法分析了近30年全球云量的变化趋势,结果表明:(1)全球近30年平均总云量约为59%,全球总云量及低云量、中云量都有明显的纬向分布特征,全球总云量有3个峰值带和3个低值带。(2)低云量的海陆分布差异较明显,陆地上的低云量明显低于海洋上的,除了两个极圈附近,南半球各纬度的低云量都比北半球相应纬度上的都要多;高云量的高值、低值中心均集中在赤道附近到南、北半球30°之间的中低纬度,并且低值中心主要分布在大洋的东部。(3)总云量的总变化趋势为增长,具体表现为随时间呈现先略减少后大幅增加趋势,其突变点大致在1993年,在1993年之后,总云量显著增多。低云量和高云量均呈现增长趋势,中云量则相反,呈减少趋势。低云量增幅最明显,接近2%,中、高云量则增减幅度较小。
制造业创新与转型:深圳创客空间调查  [PDF]
谢莹,童昕,蔡一帆
科技进步与对策 , 2015, DOI: 10.6049/kjjbydc.2014070042
Abstract: 创客(Maker)是近年来基于开源软硬件发展而兴起的新型制造业创新模式。实地考察了深圳“创客圈”,详细描述了深圳“创客圈”的演变历程、主要活动空间的分工及联系,并论述了深圳创客空间与全球生产链及本地生产系统之间的联系机制。研究发现,创客模式将在知识分享、生产组织方式转型和人力资本优化3个方面对珠三角制造业升级产生积极影响,地方产业政策需要从优化创客模式的机制入手,改变传统产业扶持政策,实现基于创新的增长方式转型。创客地方创新系统制造业创新产业转型产业升级
威客平台信誉能力评价机制研究  [PDF]
刘 寅,吴毅坚,彭 鑫,赵文耘?
计算机科学 , 2012,
Abstract: witkey(威客)模式鼓励网民将自身专业知识、技能、经验、能力通过社区转换成具有经济价值的知识产品并与他人分享。但目前的威客网站的信誉评价机制都比较简单,无法很好地反映威客的真实信誉能力,不利于项目雇主选择合适的合作伙伴。针对软件项目领域开发者的技术和信誉能力特点,提出了一套结合客观度量、主观评价的威客信誉能力评价模型。实验中,采用典型的场景模拟了威客在平台上的成长历程,分析了使用该模型的评价结果对威客成长的引导作用,从而验证了该评价模型的可行性和可用性。
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