排序方式： 共有68条查询结果，搜索用时 16 毫秒
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Bruno Calderoni Giuseppe Cecere Emilia Angela Cordasco Luigi Guerriero Pietro Lenza Gaetano Manfredi 《Journal of Cultural Heritage》2010,11(2):163-171
The knowledge of the morphological and mechanical properties of masonry walls is very important for the refurbishment of ancient buildings, particularly when the requirements of both structural safety and historical preservation must be fulfilled. The masonry is not of homogenous material: its mechanical properties depend on stones, mortar, and texture which are very variable due to their dependence on the historical periods and the geographical area of the erection. For this reason, a deep knowledge of masonries built in different sites and historical periods is essential in order to evaluate both the capacities of bearing vertical load and the seismic vulnerability of the masonry structure. Three fundamental typologies of tuff masonry have been defined: they are the characteristics of different historical periods from the XVI to the XX century. The models are in full-scale in order to reproduce the three defined chronotypes. Original tuff stones quarried in the corresponding historical period, mortars similar to the original ones, reproduced according to ancient documents and original constructive techniques have been used for the construction of the specimens. Compression tests performed in displacement control have been carried out on the masonry models in order to determine the maximum resistance of the material and the corresponding strain, the ultimate strain and corresponding residual strength. In this paper, the procedure used for making the specimens and for experimentally evaluating the mechanical properties of post-medieval Neapolitan yellow tuff masonry are illustrated and the obtained results, even in terms of plastic capacity of these kinds of masonry, are reported. 相似文献
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Maria Emilia Ricardo Marques 《Educational Media International》2013,50(3):119-123
Abstract This article discusses the role played by socio‐educational documents, from schools or local media libraries, in the everyday life of the linguistic minority learner. 相似文献
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Emilia Afonso Nhalevilo 《Cultural Studies of Science Education》2012,7(2):447-450
This paper is a response to Maria Andree’s paper. Andree tells in the paper how mistakes in practical lessons may be critical
events to change students’ attitudes in regard science. While traditionally mistakes in practical lessons could obligate students
to repeat the experiment in order to get the ‘right result’ in the paper we have a good example how we can use the incident
to potentiate students’ participation. In my response I illustrate how transferable is what Andree speaks about but I put
forward further reflections about the traditions that may act as impediment for students’ participation. I thus suggest that
the critical paradigm should be a component in reflecting about science classroom practices in order to alter the traditions. 相似文献
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Cristina Akiko Iizuka Welber Marinovic Afonso Antonio Machado Luiz Henrique Porto Vilani 《体育科研》2005,26(3):73-75
多维焦虑理论认为认知和躯体焦虑对运动成绩会产生不同的影响.根据这个理论,运动员在赛前具有较高的认知焦虑水平或躯体焦虑水平出现极端值(过高或过低)或自信心较低时,他们将取得较差的运动成绩.先前的研究还认为焦虑与运动成绩间的关系还取决于所要完成动作的特点.不同的运动技能有各自最佳的焦虑水平.总的来说,焦虑水平较高有利于完成体力消耗较大的运动项目.而焦虑水平较低时,则有利于完成精确类项目.就乒乓球项目而言,它既需要体力又需要精确性,因此,本研究调查分析了乒乓球运动员赛前焦虑水平与运动成绩间的关系.研究对象3 6名青少年乒乓球运动员,男、女运动员各1 8名,平均年龄为12.28±0.74岁.研究方法采用运动竞赛状态焦虑量表(CSAI-2C).让运动员在参加地区赛第一场比赛的赛前30分填写问卷.研究结果认知状态焦虑水平不能用来预测运动员的成绩.获胜运动员和失利运动员赛前的躯体状态焦虑和自信心没有差异.这表明本研究没有支持多维焦虑理论的假设,或许是乒乓球运动的特点和运动员的个体差异比运动员的焦虑水平对运动成绩的影响更大.因此,如果运动员的个人特点与他们的技术风格相适应,不同焦虑水平的运动员都可能取得好成绩. 相似文献
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Investigations of people's understanding of the evolution of species have focused mainly on secondary school and university students. Very few investigations have taken into consideration younger students, and none have related children's ideas about the origin of species to formal instruction on this topic. To help fill this gap, the present study examines the effect of this instruction in elementary school children by comparing Italian second graders (n = 21; age = 7 years, 1 month, to 8 years, 7 months) with third graders (n = 18; age = 8 years, 1 month, to 9 years, 4 months) who had been taught about “the earth before humans” for several months in keeping with the Italian National Syllabus for this grade level. Semistructured interviews were used to examine children's thoughts about speciation. The majority of second graders used a creationist framework, whereas most third graders used a mixed framework (referring to both creation and evolution) or an evolutionary framework. However, children did not know about the mechanism of evolution and considered it to be the result of the passage of time, the use and disuse of body parts, or the need to adapt to a changing environment, as suggested by their teacher and textbooks. 相似文献
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Jettison is the practice of throwing goods overboard in order to lighten and consequently save a vessel, as well as the lives of those on board. This phenomenon has long been part of seafaring, with the dangers of navigation not having changed since ancient times. Accordingly, various bodies of maritime law emerged in the medieval era to handle the consequences of such events. This article will discuss how the principles of jettison and general average introduced by the Lex Rhodia and maintained in Roman law were understood in some medieval regulations. Although most legal texts indicate a common understanding of the principles of general average, opinions vary widely on details of procedure and events covered by the rulings. This analysis will show how the rules of jettison and general average are treated in different contexts and by the diverse societies administering them. 相似文献
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Biffi E Piraino F Pedrocchi A Fiore GB Ferrigno G Redaelli A Menegon A Rasponi M 《Biomicrofluidics》2012,6(2):24106-2410610
Spatially and temporally resolved delivery of soluble factors is a key feature for pharmacological applications. In this framework, microfluidics coupled to multisite electrophysiology offers great advantages in neuropharmacology and toxicology. In this work, a microfluidic device for biochemical stimulation of neuronal networks was developed. A micro-chamber for cell culturing, previously developed and tested for long term neuronal growth by our group, was provided with a thin wall, which partially divided the cell culture region in two sub-compartments. The device was reversibly coupled to a flat micro electrode array and used to culture primary neurons in the same microenvironment. We demonstrated that the two fluidically connected compartments were able to originate two parallel neuronal networks with similar electrophysiological activity but functionally independent. Furthermore, the device allowed to connect the outlet port to a syringe pump and to transform the static culture chamber in a perfused one. At 14 days invitro, sub-networks were independently stimulated with a test molecule, tetrodotoxin, a neurotoxin known to block action potentials, by means of continuous delivery. Electrical activity recordings proved the ability of the device configuration to selectively stimulate each neuronal network individually. The proposed microfluidic approach represents an innovative methodology to perform biological, pharmacological, and electrophysiological experiments on neuronal networks. Indeed, it allows for controlled delivery of substances to cells, and it overcomes the limitations due to standard drug stimulation techniques. Finally, the twin network configuration reduces biological variability, which has important outcomes on pharmacological and drug screening. 相似文献
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Emilia Ferreiro 《Infancia y Aprendizaje》2019,42(1):1-36
This text presents an epistemological option for beginning literacy which departs from traditional options in several respects: (1) objectivity is not assumed as a starting point but as an ending fact (as an aspiration more than a reality); (2) all research communities adopt certain paradigms as their unquestioned ‘epistemic framework’ which serve to validate methodological and theoretical approaches without discussion; (3) situating oneself at the boundaries of this ‘unquestioned scientificity’ reveals useful data worth bearing in mind in the specific field discussed here: the early stages of the cognitive approach to the object of ‘written language’. This text defends the empirical interest of Jean Piaget’s theory to incorporate a theoretical object not thematized by this researcher: written language. It debates the irrelevance of interpretations inspired by Piaget yet based on a purely applicationist vision of the theory. Constructivism is constructed by testing new hypotheses on new objects. That is the persistent message of this text, which provides data to support each claim about development. 相似文献