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    题名 作者 年代 出处 被引量
1Stochastic structural model of rock and soil aggregates by continuum-based discrete element method显示文摘This paper first presents a stochastic structural model to describe the random geometrical features of rock and soil aggregates. The stochastic structural model uses mixture ratio, rock size and rock shape to construct the microstructures of aggregates, and introduces two types of structural elements (block element and jointed element) and three types of material elements (rock element, soil element, and weaker jointed element) for this microstructure. Then, continuum-based discrete element method is used to study the deformation and failure mechanism of rock and soil aggregate through a series of loading tests. It is found that the stress-strain curve of rock and soil aggregates is nonlinear, and the failure is usually initialized from weaker jointed elements. Finally, some factors such as mixture ratio, rock size and rock shape are studied in detail. The numerical results are in good agreement with in situ test. Therefore, current model is effective for simulating the mechanical behaviors of rock and soil aggregates.WANG Yuannian1, ZHAO Manhong1, LI Shihai1 & J.G. Wang21. Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China 2. Tropical Marine Science Institute, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260 2005Science China(Technological Sciences)2005,48,z1:21
2植物器官体积微变化与果树自动化灌溉显示文摘植物某些器官体积呈周期性锯齿状的波动变化,其变化动态与植物体内的水分状况密切相关.根据植物器官体积微变化动态来指导农作物自动化灌溉的新技术——植物器官体积变化连续测微法指导灌溉能较理想地满足果树对水分营养的需求.作者侧重地分析了热效应,组织间的水分交流,组织的生长在植物贮藏水分器官体积微变化动态中所起的作用;讨论了两种不同类型,植物体内贮藏水分高消费型和植物体内贮藏水分经济利用型的果树作物的贮藏水分器官在土壤水分可利用性降低过程中的一般体积微变化动态规律;介绍了使用植物器官体积变化连续测微法指导果园灌溉的一些基本原则.李绍华 Huguet J.G. 1993果树学报1993,13,S1:17
3STRUCTURE FORMATION OF UNDERCOOLED Fe-30Ni ALLOY显示文摘Bulk Fe-30Ni alloy melt was nudercooled up to 337K by combining the glass fluxing technique with superheating-cooling cycle. Grain refinement at low undercoolings was observed in the experiment in addition to that at high undercoolings. The current grain refinement mechanisms were examined, and it is concluded that the refined gains are all developed from dendrites, however the grain refinement at low undercoolings is due to chemical superheating, while that at high undercoolings due to rapid solidification contruction.J.F. Li, J.G. Li, X.P. Zhang and Y.H. Zhou (School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200030, China) 2000Acta Metallurgica Sinica(English Letters)2000,13,5:10
4四元教学设计模式主要设计原理显示文摘本报告旨在说明四元教学设计模式的主要特征。首先,报告说明了构建基于能力教育的四个元素。其次,报告简要说明了基于四个元素的课程综合如何帮助实现学习迁移。再次,报告描述了四元教学设计的系统设计过程,重点是本模式规定的主要教学设计原则。报告以简短的讨论结束,说明4C/ID模式在教育科学领域的定位。 盛群力(译) 2020开放教育研究2020,26,3:10
5A Review of Botulism in China显示文摘The epidemiological characteristics and etiology of botulisin in China, as well as the distribution of different types of Clustridium bolulinum in China; are described.Through 1989, 15 provinces and autonomous regions reported the occurrence of botulism.There were 2861 cases involved in 745 outbreaks.Among the cases 421 died, with a case fatality of 14.7%.The main epidemiological characteristics of botulism in China are: (i) the major foods causing botulism are homemade fermented bean products which accounted for 62.6% of the cases; (ii) the incubation period is longer (3 h-54 days) than that described in the western literature (mostly 2-7 days); (iii) the peak occurrence is from February to May; (iv) the progression of symptoms and signs is slower than that of western cases.All types of C.bolulinum.with the exception of type G, have been found in China.The distribution of various types of C.botnlinum is significantly different between southern and northern China; this is related to the latitude and is correlated with the prevalence of this disease.Most of the botulism outbreaks occurred above 30° north latitude in northern China and outbreaks rarely occurred below 30° north latitude.Nationwide surveys showed that the average detection rate of C bolulinum spores in soil and foods in the northern parts of China was 14.8%.while it was only 2.5% in the south.C.bolulinum types A, B, E.and F, which are involved in human botulism, were frequently found in the North, while types C and D, which are involved only in animal intoxication, were found more frequently in the south. 1990 Academic Press.Inc.GAO Q.Y. HUANG Y.F. WU J.G. LIU H.D. XIA H.Q 1990Biomedical and Environmental Sciences1990,3,3:8
6认知负荷理论:教学设计原则与策略——兼谈在健康专业教育中的应用显示文摘首创于20世纪80年代并在不断蓬勃发展的认知负荷理论,对人的认知架构提出了新的假设。处理感觉记忆和长时记忆获得的信息,工作记忆的容量限度是不一样的。图式建构和图式熟练是学习过程的两种基本样式,由此需要做到减轻外在认知负荷、调控内在认知负荷和优化相关认知负荷,这也是教学设计的总体要求。通过各种研究加以总结提炼的15条教学设计原则与策略,为提升健康教育乃至其他专业教育的教学效能提供了新的视野。这些原则与策略随着学习者经验和专长的积累,会产生'反转效应'。杰伦J.G.范梅里恩伯尔 约翰.斯维勒 钟丽佳 盛群力 2015当代教育与文化2015,7,6:8
7A comparison of transmittance properties between ZnO∶Al films for transparent conductors for solar cells deposited by sputtering of AZO and cosputtering of AZO/ZnO显示文摘Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.LEE Chongmu YIM Keunbin CHO Youngjoon Lee J.G. 2006Rare Metals2006,25,z1:8
8FE SIMULATION OF CENTER CRACK OCCURRENCE IN TUBE ROUNDS DURING TWO-ROLL ROTARY ROLLING PROCESS显示文摘With the aid of FE (finite element) code MSC.Superform 2005, 2-D coupled thermo-mechanical simulation of center-crack occurrence in round billet during 2-roll rotary rolling process was presented using Oyane ductile fracture criteria. A simple modeling is put forward based on the spiral motion of the workpiece as an essential characteristic in movement. The influence of the feed angle and the entry cone angle of the main roll on the process was taken into account in the modeling. The soundness for simplifying the 3-D rotary rolling into a 2-D problem was discussed. By adopting the parameters of Diescher piercer in 140mm mandrel mill of Bao Steel, the distribution and development of strain / stress were analyzed, and the eigen value of ductile fracture as well. The critical percentage of diameter reduction was obtained from the simulation. The result showed a good agreement with the experimental value, and therefore was of widely guiding significance to the practical process for rationally formulating the deformation parameters of steel tube piercing.S.Z. Li J. Xu Y.D. Yin J.G. Xue F. Pan J.M. Zheng J.H. Yoon 2007Acta Metallurgica Sinica(English Letters)2007,20,3:7
9论问题解决与教学促进显示文摘大多数教育工作者都认为问题解决很重要,但是他们对什么是问题解决持有不同观点,在怎样教给学生问题解决的本领上也没有达成一致意见。各种不同观点主要集中于将问题解决视为教育目标、教育方法以及技能训练之间的差异问题上。其一,目标型问题解决不应只限于良构问题解决,而应该延伸到现实问题解决;其二,对初学者来说,方法型问题解决有其明显的局限性,给予这些学习者足够帮助,对于培养他们的问题解决能力具有重要作用;其三,技能型问题解决不应被看作是只在培养专长过程的初期才会出现,而应被视为在系统1模式与系统2模式中平行发展的一个过程。总结以上观点,综合学习设计模式完全可以用来促进此三种类型的问题解决,并其本回答了问题解决最好应该怎样教的问题。杰伦J.G.范梅里恩伯尔 毛伟 盛群力 2014远程教育杂志2014,32,6:7
10学习科学和教学设计背景下的“四元教学设计模式”显示文摘'四元教学设计模式'(4C/ID)是一种面向综合学习的教学设计方法,即学习旨在实现综合目标,并且同时发展知识、技能和态度,以获得综合能力和专业能力。四元教学设计模式是20世纪80年代后期,由国际著名教学设计专家范梅里恩伯尔教授研发的,目前已经成为最有影响力的教学设计模式之一,广泛应用于职业技术教育和普通教育中。四元教学设计包括了学习任务、相关知能、支持程序和专项操练四个要素,实际应用中还可以扩展为十个步骤。这些步骤阐述了教学设计者常用的设计过程,以达成有效果、有效率和有魅力的面向综合学习的学业培养方案。该模式有很强的研究基础,已有数百项实验研究支持4C/ID模式所提出的理论。杰伦·J.G.范梅里恩伯尔 保罗·A.基尔希纳 章褚昀(译) 盛群力(校) 2019开放学习研究2019,0,3:7
11Design-oriented stress–strain model for FRP-confined concrete显示文摘L. Lam J.G. Teng 2003Construction and Building Materials2003,,6:5
12论学习的研究范式与视界显示文摘影响人的学习的最重要因素是什么?不同的教学理论对此给出了大相径庭的答案,这是因为它们各自对学习本身持有不同的视界,有的看重预期的学习结果,有的聚焦影响学习过程的各种方法,还有一些则抓住了学习发生的条件。有八种对教育传播与技术领域的理论发展一直产生影响,并且仍在产生强烈影响的最流行研究范式,它们分别是完形心理学、行为主义和新行为主义、发展心理学、文化—历史学派、信息加工理论、认知符号理论、认知资源理论和社会建构主义。一般来说,研究总是在某个特定的范式框架内进行的,但是研究者应该认识到,范式本身会对研究方法和结果产生很深的影响。更重要的是,研究者应该对各种不同的理论与范式持开放的心态,因为新的发现总是出现在不同范式之间的交叠磨合处。杰罗姆J.G.范梅恩伯尔 安妮奎B.H.de布莱恩 盛群力 柴巧君 2012远程教育杂志2012,30,4:5
13早期血运重建与急性心肌梗死并发心源性休克患者远期存活率的关系Hochman J.S. Sleeper L.A. Webb J.G. 任付先 2006世界核心医学期刊文摘(心脏病学分册)2006,0,11:4
14动脉粥样硬化和基质金属蛋白酶:活体分子MR成像实验研究显示文摘目的评价以基质金属蛋白酶(MMPs)作为靶目标的分子MR成像对比剂P947检测和成像活体动脉粥样硬化病变中基质金属蛋白酶的能力:比较其与P1135的特异度:明确基质金属蛋白酶在动脉粥样硬化血管中的表达与分布:应用荧光标记P947(Eu—P947)在体内的分布和分子定位。方法动物保护与应用委员会批准进行所有实验。将钆螯合物(1,4,7,10-tetraazacvclododecane-N,N_,N_,N_—tetraaceticacidl与一能与MMPs特异结合的多肽黏附合成P947。V. Amirbekian J.G. Aguinaldo S. Amirbekian F. Hyafil E. Vucic M. Sirol 郭瑜(译) 葛夕洪(校) 2009国际医学放射学杂志2009,32,4:4
15火文化的三个时代显示文摘我们所浏览的关于火种的神话传说足以说明:如何发现火和取火方式的问题是非常深奥的。其中凝结着几十万年世界各地人民的智慧与才能。从整体上来看,这些故事似乎反映出这样一种普遍观念,即人类在进化的过程中曾经历过有关火的三个阶段:第一阶段是人类尚未懂得使用火,甚至不知道火的存在;第二阶段是拥有火并用它取暖和烧烤食物,但仍不晓取火方法;J.G.弗雷泽 赵捷 1987云南民族大学学报(哲学社会科学版)1987,8,2:4
16阿芙罗狄忒的象征显示文摘中国史前及商周时代的遗址中出土了数量不小的海贝及仿制的骨贝.现在一般认为贝有两种用途:第一用于装饰;第二用作货币。但是,许多民族学的材料昭示我们,海贝——因其独特的外形及蕴含的繁殖功能而被视为生命之符。安特生先生的著作收集大量的考古和民族志材料论证了海贝作为生命之符的可能性,具有很高的学术价值。本文系安代《黄土的儿女》中的第十九章,现译出来,以纪念仰韶文化发掘七十周年。为了方便读者,译者在文中加了一些必要的注释,并对无关宏旨的东西作了删节。J.G.安特生 陈星灿 1992南方文物1992,,3:4
17N末端脑利钠肽(NT-proBNP)对硬皮病相关性肺动脉高压的作用显示文摘Aims: The aims of this study were to evaluate the diagnostic value and to explore the prognostic value of N-terminal brain natriuretic peptide(N-TproBNP) in patients with systemic sclerosis(SSc) both with and without pulmonary arterial hypertension(PAH). Methods and results: N-TproBNP, six minute walk distance(SMWD), haemodynamics(at right heart catheterization) or tricuspid gradient(by echocardiography), and survival were assessed in 109 patients with SSc. The study population included 68 individuals with PAH[mean pulmonary artery pressure(PAP) >25 mmHg and pulmonary capillary wedge pressure< 15 mmHg] and 41 individuals without PAH. In patients with PAH, the prognostic value of baseline and change in WHO functional class, N-TproBNP levels, and SMWD were compared using Kaplan-Meier survival curves and Cox proportional hazard analysis. The mean duration of follow-up was 10 months(range 1-18 months). One year survival in patients with normal PAP was 100%when compared with 83.5%in those with SSc-PAH(P< 0.05). The patients without PAH had a mean N-TproBNP level of 139 pg/mL(SD 151); those with SSc-PAH had a significantly higher mean NTproBNP level of 1474 pg/mL(SD 2642)(P=0.0002). Among patients with PAH for every order of magnitude increase in N-TproBNP level there was a four-fold increased risk of death(P=0.002 for baseline level and P=0.006 for follow-up level). Baseline N-TproBNP levels were correlated positively with mean PAP(r=0.62; P< 0.0001), pulmonary vascular resistance(PVR)(r=0.81; P< 0.0001), and inversely with SMWD(r=-0.46; P< 0.0001). Among patients with SSc-PAH, 13 patients(19%) were in WHO functional classes Ⅱ and had mean NTproBNP levels of 325 pg/mL(SD 388). Fifty-three patients(78%) were in WHO classes Ⅲ and IV and had significantly higher mean N-TproBNP levels of 1677 pg/mL(SD 2835)-(P=0.02). At an N-TproBNP level of 395 pg/mL, the sensitivity and specificity for predicting the presence of SSc-PAH were 56 and 95%respectively. Conclusion: Raised N-TproBNP levels are directly related to the severity of PAH. In screening programs, SSc patients with an N-TproBNP in excess of 395 pg/mL have a very high probability of having pulmonary hypertension. Baseline and serial changes in N-TproBNP levels are highly predictive of survival. A 10-fold increase in N-TproBNP level on therapy is associated with a greater than three-fold increase in mortality, and may indicate therapeutic failure.Williams M.H. Handler C.E. Akram R. J.G. Coghlan 郭俊 2006世界核心医学期刊文摘(心脏病学分册)2006,,12:4
18物理环境对认知负荷和学习的影响:认知负荷新模型探讨显示文摘认知负荷理论框架承认学习环境的作用,然而从理论和实证两个角度看,物理学习环境影响认知负荷的具体特征尚未涉及。本文研究了物理学习环境对认知负荷的影响,认为它是教学有效性的决定因素,同时对帕斯和范梅里恩伯尔20余年前提出的'认知负荷模型'进行更新,将物理学习环境看成是独立的因果要素,与学习者特征、学习任务特征或两者结合后产生互动。本文还探讨了前人有关物理学习环境对认知能力影响的研究,以及对新的认知负荷研究的启发,并对该领域未来研究方向提出了设想。 杰伦·J.G.·范梅里恩伯尔 弗莱德·帕斯 2018开放教育研究2018,24,1:3
19Anaerobic ammonium oxidation discovered in a denitrifying fluidized bed reactor显示文摘A. Mulder A.A. van de Graaf L.A. Robertson J.G. Kuenen 1995FEMS Microbiology Ecology1995,,3:3
20肺静脉的常规处理及无缝合技术处理:适应证从修复术后肺静脉狭窄到早期肺静脉异常的演变Coles J.G. Konstantinov I.E. 刘少伟 2005世界核心医学期刊文摘(心脏病学分册)2005,0,6:3
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