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171.
The protection of works of art and cultural assets against light-induced aging is vital when planning exhibitions. Newly developed lighting systems render the selection of suitable light sources more difficult, not least in the context of energy–economical systems. This study accordingly examines different lighting systems (fluorescent tubes, halogen lamps, low-voltage metal halide lamps, and LED lamps) in terms of the damage potential they hold for the materials concerned. The changes in color were evaluated using the CIEDE2000 color-difference formula. This study focuses on selected organic materials and shows that changes in color already occur after only a brief exposure time. The color changes induced by the fluorescent tubes were consistently more intense than those induced by the other light sources. The results obtained with the remaining lamps show that the color changes depend more on the material under investigation than on the source used. The changes determined after a relatively short exposure period (five months) vividly demonstrate that exposing sensitive materials to light for longer terms (as is the case during a permanent exhibition) is most definitely a non-viable option.  相似文献   
172.

Objective

The aim of the current study was to evaluate the effect of ultraviolet (UV) photofunctionalization of dental titanium implants with exposure to the oral cavity on osseointegration in an animal model.

Methods

Forty-eight titanium implants (Camlog® Conelog® 4.3 mmx9.0 mm) were placed epicrestally into the edentulous jaws of three minipigs and implant stability was assessed by measuring the implant stability quotient (ISQ). Prior to implantation half of the implants were photofunctionalized with intense UV-light. After three months, the implants were exposed and ISQ was measured again. After six months of implant exposure, the minipigs were sacrificed and the harvested specimens were analyzed using histomorphometric, light, and fluorescence microscopy.

Main results

Forty-two of 48 implants osseointegrated. The overall mean bone-implant contact area (BIC) was (64±22)%. No significant differences were found in BIC or ISQ value (multivariate analysis of variance (MANOVA), P>0.05) between implants with and without exposure to UV photofunctionalization.

Conclusions

No significant effects were observed on osseointegration of dental titanium implants nine months after exposure of UV photofunctionalization.
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175.
Early social relationships: a psychobiologist's view   总被引:2,自引:0,他引:2  
This article outlines a strategy for studying early social relationships in relatively simple animal model systems. It describes some of the differences in approach between neuroscientists and human developmentalists in dealing with the same research problems. These ideas are then illustrated in work from our laboratory on the processes of early social attachment in young rats and on their responses to separation from their mothers. We have found evidence for a novel mechanism by which the mother appears to be a regulator of physiological and behavioral systems of the infant so that many of the prolonged responses to separation represent withdrawal or release phenomena. Finally, I will describe some surprising results from our studies on the organization of nursing that reveal an unexpected degree of synchrony and reciprocity in this apparently simple interaction that is so basic to being a mammal.  相似文献   
176.

When it comes to biology lessons in Germany, girls generally exhibit higher levels of self-determined motivation than boys. Previous research suggests that fostering student autonomy could be a way to effectively address this gender gap. To investigate gender-related effects in biology education, a sample of 303 sixth-grade students (Mage = 11.31 years, SDage = 0.58 years) participated in a 3-h teaching unit on harvest mice that was taught in either an autonomy-supportive or controlling manner. The results revealed a significant effect of the treatment on self-determined motivation, with the effect being stronger for the boys. In the treatment with controlling teaching behavior, gender-related differences in self-determined motivation became apparent. In contrast, the gender gap was mainly smaller in the treatment with autonomy-supportive teaching behavior. Thus, the results suggest that satisfying the need for autonomy appears to be an effective means to help bridge the gender gap in biology lessons.

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177.
This paper argues against the moral Turing test (MTT) as a framework for evaluating the moral performance of autonomous systems. Though the term has been carefully introduced, considered, and cautioned about in previous discussions (Allen et al. in J Exp Theor Artif Intell 12(3):251–261, 2000; Allen and Wallach 2009), it has lingered on as a touchstone for developing computational approaches to moral reasoning (Gerdes and Øhrstrøm in J Inf Commun Ethics Soc 13(2):98–109, 2015). While these efforts have not led to the detailed development of an MTT, they nonetheless retain the idea to discuss what kinds of action and reasoning should be demanded of autonomous systems. We explore the flawed basis of an MTT in imitation, even one based on scenarios of morally accountable actions. MTT-based evaluations are vulnerable to deception, inadequate reasoning, and inferior moral performance vis a vis a system’s capabilities. We propose verification—which demands the design of transparent, accountable processes of reasoning that reliably prefigure the performance of autonomous systems—serves as a superior framework for both designer and system alike. As autonomous social robots in particular take on an increasing range of critical roles within society, we conclude that verification offers an essential, albeit challenging, moral measure of their design and performance.  相似文献   
178.
Teleology has been described as an intuitive cognitive bias and as a major type of student conception. There is controversy regarding whether teleological explanations are a central obstacle to, are legitimate in, or are even supportive of science learning. However, interaction in science classrooms has not yet been investigated with regard to teleology. Consequently, this study addresses the question of how teleological explanations emerge in science classroom interactions about evolution and how teachers and students address emerging teleology. In this article, we introduce a theoretical and methodological framework drawing from the sociology of knowledge and systems theory, suggesting that this framework may enrich the understanding of knowledge construction and of social practices in the science classroom because it enables distinguishing between explicit and tacit knowledge. We investigated seven secondary school units about evolution and present data from four grade-12 classes in Germany, a country with very few creationists, to contrast two ways in which teleology is addressed. In the first type, the teachers combine intentional and need-based teleological explanations with aspects of scientific theories in an ambiguous way. Contrastingly, in the second type, the teachers construct a duality between correct mechanistic and incorrect teleological explanations by discrediting preceding scientific theories. In the discussion, we argue that the presented sociological approach can also be valuable in other science education contexts, such as creationism, the nature of science and socio-scientific issues, because classroom interaction involves tacit communication, such as a tacit epistemology, which are essential grounds for the students' knowledge construction.  相似文献   
179.
Early mathematics knowledge is a strong predictor of later academic achievement, but children from low‐income families enter school with weak mathematics knowledge. An early math trajectories model is proposed and evaluated within a longitudinal study of 517 low‐income American children from ages 4 to 11. This model includes a broad range of math topics, as well as potential pathways from preschool to middle grades mathematics achievement. In preschool, nonsymbolic quantity, counting, and patterning knowledge predicted fifth‐grade mathematics achievement. By the end of first grade, symbolic mapping, calculation, and patterning knowledge were the important predictors. Furthermore, the first‐grade predictors mediated the relation between preschool math knowledge and fifth‐grade mathematics achievement. Findings support the early math trajectories model among low‐income children.  相似文献   
180.
This intervention study examines the different effects that work on video- or text-based teaching cases has on improving feedback-related performance (dependent variable) for trainee PE teachers. Within a teaching-learning arrangement, one group (n?=?24) worked with video-based teaching cases while another group (n?=?9) worked with text-based ones. In addition, both groups completed a school practicum. Additionally, a control group (n?=?23) completed the practicum, without any teaching case intervention. The quality of the feedback-related performance of the trainee PE teachers was recorded using video vignettes both before and after the respective interventions and then evaluated on the basis of an external assessment (expert rating). The results show that the work on video- and text-based teaching cases was effective, but that the videobased procedure had more of an impact, with a high level of practical significance. The control group was unable to improve on the basis of the placement within a school. The results demonstrate their usefulness for future training and competence diagnostics.  相似文献   
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