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91.
Stochastic differential equation (SDE) models are a promising method for modeling intraindividual change and variability. Applications of SDEs in the social sciences are relatively limited, as these models present conceptual and programming challenges. This article presents a novel method for conceptualizing SDEs. This method uses structural equation modeling (SEM) conventions to simplify SDE specification, the flexibility of SEM to expand the range of SDEs that can be fit, and SEM diagram conventions to facilitate the teaching of SDE concepts. This method is a variation of latent difference scores (McArdle, 2009; McArdle & Hamagami, 2001) and the oversampling approach (Singer, 2012), and approximates the advantages of analytic methods such as the exact discrete model (Oud & Jansen, 2000) while retaining the modeling fiexibility of methods such as latent differential equation modeling (Boker, Neale, & Rausch, 2004). A simulation and empirical example are presented to illustrate that this method can be implemented on current computing hardware, produces good approximations of analytic solutions, and can flexibly accommodate novel models. 相似文献
92.
Guylaine Le Jan Régine Le Bouquin-Jeannès Nathalie Costet Nolwenn Trolès Pascal Scalart Dominique Pichancourt Gérard Faucon Jean-Emile Gombert 《Annals of dyslexia》2011,61(1):1-20
Dyslexia is a specific disorder of language development that mainly affects reading. Etiological researches have led to multiple
hypotheses which induced various diagnosis methods and rehabilitation treatments so that many different tests are used by
practitioners to identify dyslexia symptoms. Our purpose is to determine a subset of the most efficient ones by integrating
them into a multivariate predictive model. A set of screening tasks that are the most commonly used and representative of
the different cognitive aspects of dyslexia was proposed to 78 children from elementary school (mean age = 9 years ± 7 months)
exempt from identified reading difficulties and to 35 dyslexic children attending a specialized consultation for dyslexia.
We proposed a multi-step procedure: within each category, we first selected the most representative tasks using principal
component analysis and then we implemented logistic regression models on the preselected variables. Spelling and reading tasks
were considered separately. The model with the best predictive performance includes eight variables from four categories of
tasks and classifies correctly 94% of the children. The sensitivity (91%) and the specificity (95%) are both high. Forty minutes
are necessary to complete the test. 相似文献
93.
94.
Five optical analyses of a given work of art are presented, using multispectral imaging, optical coherence tomography, goniophometry, UV-fluorescence emission spectroscopy and diffuse reflectance spectroscopy. All these methods are non-destructive, contactless, and implementable in situ. They all lead to results in quasi-real time. The multispectral camera allows imaging of the whole painting with very high definition and recording of 240 millions of spectra. Optical coherence tomography allows local 2D and 3D imaging with in-face and in depth stratigraphies inside the painting with a micrometric accuracy. It allows the evaluation of the pigment volume concentration inside a layer, the measurement of the thickness of one or two varnish layers, the detection and measurements of gaps inside the paint layer, the depth of varnish micro-cracks. Goniophotometry allows the measurement of the upper surface state of the painting in different locations, by quantifying the mean slope of the facets making up the surface. UV-fluorescence emission spectroscopy allows the identification of the resin, the binder and the ageing state of varnishes by use of databases of reference varnishes. Diffuse reflectance spectroscopy leads to pigment, pigment mixture and dye identifications again by use of databases. The three last methods are implemented with the same portable multi-function instrument. It allows time saving, locations on request in front of the artwork and easy use by non-scientists. Each instrument is described with its protocol and accuracy. The studied painting is a portrait of a lady painted by the Austrian artist Franz Strotszberg, chosen for its several restorations. The five kinds of results are successively detailed, analysed and compared between themselves. It is shown that the different results are complementary and their crosschecking brings thorough information. For example, the shape of the network of varnish micro-cracks detected on the surface with the multispectral camera is added to the measurement of their depth with optical coherence tomography. Another example allows connecting two different surface states of the upper varnished surface measured by goniophotometry with the identification of these varnish with UV-fluorescence and with their thicknesses measured with optical coherence tomography. 相似文献
95.
Bio-electrosprays (BESs) provide a means of precisely manipulating cells and thus have the potential for many clinical uses such as the generation of artificial tissues∕organs. Previously we tested the biological safety of this technology with a variety of living cells and also embryos from the vertebrate model organisms Danio rerio (zebrafish) and Xenopus tropicalis (frog). However, the viability and fertility of the treated embryos could not be fully assessed due to animal licensing laws. Here we assay the viability and fertility of Drosophila melanogaster (fruit fly) embryos in conjunction with the bio-electrospray procedure. Bio-electrosprayed Drosophila embryos developed into fully fertile adult flies that were indistinguishable from wild-type. Thus, we demonstrate that the bio-electrospray procedure does not induce genetic or physical damage that significantly affects the development or fertility of a multicellular organism. This study along with our previous investigations demonstrates the potential of this approach to be developed for the precise manipulation of sensitive biological materials. 相似文献
96.
The aim of this study was to examine the potential motivational and behavioural benefits of two peer tutoring programmes for tutors in a sport setting. Differences between the sexes were also explored. Thirty two college-age males and females, all novices on a French boxing task, were assigned to a 2 x 2 [sex x training type: physical practice associated with trained peer tutoring (TPT) vs physical practice associated with untrained peer tutoring (UPT)] factorial design. All participants were given six French boxing lessons of 2 h each. The TPT programme included structured methods to prepare the participants to fulfil their role of tutors, whereas the UPT programme did not. The results demonstrated that the TPT programme resulted in higher scores for coaching skills. Furthermore, interaction effects revealed that the TPT programme yielded better offensive outcomes for males and better defensive outcomes for females. Although the UPT participants expressed higher self-efficacy, no differences emerged for intrinsic motivation and causal attributions. Finally, male tutors displayed higher self-efficacy and offensive outcomes than female tutors. The results are discussed in the light of previous findings in the educational and sport psychology literature. 相似文献
97.
98.
We report how cell rheology measurements can be performed by monitoring the deformation of a cell in a microfluidic constriction, provided that friction and fluid leaks effects between the cell and the walls of the microchannels are correctly taken into account. Indeed, the mismatch between the rounded shapes of cells and the angular cross-section of standard microfluidic channels hampers efficient obstruction of the channel by an incoming cell. Moreover, friction forces between a cell and channels walls have never been characterized. Both effects impede a quantitative determination of forces experienced by cells in a constriction. Our study is based on a new microfluidic device composed of two successive constrictions, combined with optical interference microscopy measurements to characterize the contact zone between the cell and the walls of the channel. A cell squeezed in a first constriction obstructs most of the channel cross-section, which strongly limits leaks around cells. The rheological properties of the cell are subsequently probed during its entry in a second narrower constriction. The pressure force is determined from the pressure drop across the device, the cell velocity, and the width of the gutters formed between the cell and the corners of the channel. The additional friction force, which has never been analyzed for moving and constrained cells before, is found to involve both hydrodynamic lubrication and surface forces. This friction results in the existence of a threshold for moving the cells and leads to a non-linear behavior at low velocity. The friction force can nevertheless be assessed in the linear regime. Finally, an apparent viscosity of single cells can be estimated from a numerical prediction of the viscous dissipation induced by a small step in the channel. A preliminary application of our method yields an apparent loss modulus on the order of 100 Pa s for leukocytes THP-1 cells, in agreement with the literature data. 相似文献
99.
Stefan Schweers Katharina Kinder-kurlanda Stefan Müller Pascal Siegers 《Journal of Map & Geography Libraries》2016,12(1):100-126
There is an increasing demand for spatial data within the social sciences as such data promise to contribute to a better understanding of how the concrete living environment influences individuals’ attitudes and behaviors. Spatial data can complement data from surveys; however, as of yet there is no spatial data infrastructure for the social sciences in Germany that facilitates merging of spatial data with survey data. This article explores avenues for creating such a spatial data infrastructure (SDI) for the social sciences in Germany. We examine the role that librarians, archivists, and curators can play in offering spatial data infrastructure services for social scientists, and show the scope and nature of necessary tasks in areas such as harmonization, archiving, dissemination, and user support. As the case of Germany is similar to that of other European countries, we expect our results to be helpful in the creation of SDIs in other countries as well. This article suggests technical and organizational measures for merging survey data and spatial data in compliance with German privacy legislation. Measures for storage and dissemination of enriched survey data, for example by providing restricted access to the data in a secured environment, also are explored. 相似文献
100.
In a course on biological psychology and neuropsychology, study questions were provided that also appeared as test questions in the course exam. This method was introduced to support students in active processing and reproduction of the study texts, and study planning. Data were gathered to test the hypothesis that study question use would be beneficial to course grades. In addition, the way in which students evaluated the method was studied. It appeared that the number of study questions answered prior to the exam had a positive effect on course grades. Students were generally positive about the use of the questions in terms of their study planning. 相似文献