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991.
This paper initiates a dialogue between the sustainable system-of-systems (SSoS) approach and one particular situated approach of activity analysis within francophone activity-centered ergonomics (FACE). This paper explores the possible cross-fertilizations between FACE and SSoS in coping with the challenge of enlargement which ergonomists have to face in order to address sustainability issues. We present how the SSoS model and FACE have currently considered the challenges of sustainable development and the theoretical-methodological principles that frame their approaches. Then, eight topics of dialogue are introduced and debated in order to open the dialogue between the two approaches where emerging lines of convergence are generated. We conclude by further discussing the complementarity between FACE and SSoS in the objectives of their approaches and the levels analysed by each approach, and by highlighting the importance of taking into account the emergent and complex aspects of systems. One possible way forward might be to “situate the sustainable system-of-systems” while also “systemizing systems of sustainable situations” for the future.  相似文献   
992.
This study tested the hypothesis that women patients with depression should perform movements more slowly and with greater variability, and their learning rate should be lower compared with age-matched healthy adult women. Three groups of adult women subjects (aged 33–37 years, women patients with mild and major depression and healthy adult women, n = 20 in each group) performed five series (20 repetitions in each series) of a speed–accuracy hand-movement task (SAT). The mean movement speed (Va) of the SAT was lower and more stable (the coefficient of variation of Va was lower) in women patients with major depression compared with those with minor depression and healthy adult women during the first series of the SAT. Only the Va and movement accuracy (path of movement, S) of the SAT varied significantly in the five learning series regardless of the subject group (healthy women subjects and women patients with minor and major depression). The intraindividual variability of reaction time, Va, maximal movement velocity to the target (tVmax), time to tVmax, and S did not change significantly in any of the groups. Our research data showed that although women patients with depression performed speed–accuracy movements more slowly, the stability of the performance of their movements and their learning rate did not differ from those of age-matched healthy adult women.  相似文献   
993.
Michael   J.   Frederick  Gordon   G.   Gallup     Jr. 《心理学报》2007,39(3):489-494
波动不对称(FA)是压力的随机性引发双侧完美对称偏离的现象,这是个体无力免受发展中不利因素(如早期营养不良)侵害的一个标志。比较个体口腔两侧牙齿的大小是一种测量FA的方法。本研究汇集了10个物种共296名个体的牙齿测量结果,测量对象包括黑猩猩(学名Pan troglodytes)、猩猩(学名Pongo pygmaeus)、大猩猩(学名Gorilla gorilla)、智人(学名Homo sapiens),以及许多化石人。分析发现,猩猩样本牙齿的FA水平要显著低于大猩猩、黑猩猩、直立人、尼安德特人和智人样本的FA水平。而与之相反的是,智人与尼安德特人样本的牙齿FA水平要显著高于其它任何一种巨猿样本的FA水平。该文提出了有关缓和的选择压力的解释  相似文献   
994.
Many studies have shown that infants prefer infant-directed (ID) speech to adult-directed (AD) speech. ID speech functions to aid language learning, obtain and/or maintain an infant's attention, and create emotional communication between the infant and caregiver. We examined psychophysiological responses to ID speech that varied in affective content (i.e., love/comfort, surprise, fear) in a group of typically developing 9-month-old infants. Regional EEG and heart rate were collected continuously during stimulus presentation. We found the pattern of overall frontal EEG power was linearly related to affective intensity of the ID speech, such that EEG power was greatest in response to fear, than surprise than love/comfort; this linear pattern was specific to the frontal region. We also noted that heart rate decelerated to ID speech independent of affective content. As well, infants who were reported by their mothers as temperamentally distressed tended to exhibit greater relative right frontal EEG activity during baseline and in response to affective ID speech, consistent with previous work with visual stimuli and extending it to the auditory modality. Findings are discussed in terms of how increases in frontal EEG power in response to different affective intensity may reflect the cognitive aspects of emotional processing across sensory domains in infancy.  相似文献   
995.
This study was aimed at revealing which cognitive processes are lateralized in visual categorizations of "humans" by pigeons. To this end, pigeons were trained to categorize pictures of humans and then tested binocularly or monocularly (left or right eye) on the learned categorization and for transfer to novel exemplars (Experiment 1). Subsequent tests examined whether they relied on memorized features or on a conceptual strategy, using stimuli composed of new combinations of familiar and novel humans and backgrounds (Experiment 2), whether the hemispheres processed global or local information, using pictures with different levels of scrambling (Experiment 3), and whether they attended to configuration, using distorted human figures (Experiment 4). The results suggest that the left hemisphere employs a category strategy and concentrates on local features, while the right hemisphere uses an exemplar strategy and relies on configuration. These cognitive dichotomies of the cerebral hemispheres are largely shared by humans, suggesting that lateralized cognitive systems already defined the neural architecture of the common ancestor of birds and mammals.  相似文献   
996.
Antifat attitudes and obesity bias are prevalent in Western society; however, little is known about the social meanings and connotations of weight-related words such as fat, overweight, and obese (e.g., Robison & Erdman, 1998). The purpose of this study was to explore college students' perceptions of weight-related terminology. Participants (n=131) completed a modified figure rating scale in which they identified male and female figure silhouettes most associated with a variety of weight-related words and personal characteristics. Additionally, participants completed a word association task and provided definitions of five weight terms. Results indicated that participants grouped weight terms into two groupings (i.e., "slender" and "heavy" weight terms) both in the figure rating task and in the word association and definition tasks. Both male and female participants selected smaller female figure silhouettes for the weight terms overweight, large, fat, and normal weight than for the male figure silhouettes. Moreover, associations between weight-related words and personal characteristics, including normal weight -physically fit and overweight -lazy, were found. The results suggest that weight-related words carry with them social meanings and values that reflect an "ideology of blame."  相似文献   
997.
A series of place learning experiments was carried out in young chicks (Gallus gallus) in order to investigate how the geometry of a landmark array and that of a walled enclosure compete when disoriented animals could rely on both of them to re-orient towards the centre of the enclosure. A square-shaped array (four wooden sticks) was placed in the middle of a square-shaped enclosure, the two structures being concentric. Chicks were trained to ground-scratch to search for food hidden in the centre of the enclosure (and the array). To check for effects of array degradation, one, two, three or all landmarks were removed during test trials. Chicks concentrated their searching activity in the central area of the enclosure, but their accuracy was inversely contingent on the number of landmarks removed; moreover, the landmarks still present within the enclosure appeared to influence the shape of the searching patterns. The reduction in the number of landmarks affected the searching strategy of chicks, suggesting that they had focussed mainly on local cues when landmarks were present within the enclosure. When all the landmarks were removed, chicks searched over a larger area, suggesting an absolute encoding of distances from the local cues and less reliance on the relationships provided by the geometry of the enclosure. Under conditions of monocular vision, chicks tended to rely on different strategies to localize the centre on the basis of the eye (and thus the hemisphere) in use, the left hemisphere attending to details of the environment and the right hemisphere attending to the global shape.This contribution is part of the special issue “Animal Logics” (Watanabe and Huber 2006).  相似文献   
998.
We investigated the effect of familiarity on people's perception of facial likeness by asking participants to choose which of two mirror-symmetric chimeric images (made from the left or right half of a photograph of a face) looked more like an original image. In separate trials the participants made this judgment for their own face and for the face of a close friend; half of them matched to a true image of the original and half matched to a mirror image of the original. In the case of matching to a friend's face presented in the familiar orientation, over 80% of participants chose the left-left composite to be a better likeness to the original, whereas only 62% showed the same left-side bias when matching to a mirror image. The difference is significant, and the result contrasts markedly with a second experiment where participants who were unfamiliar with the faces showed comparable left-side biases when matching to true or mirror reversed images. The result suggests that perceptual asymmetries are retained in our long-term memory for highly familiar faces. While matching to images of self also showed an effect of familiarity, the data in this condition show less evidence of perceptual asymmetry and are discussed in relation to recent research on the representation of one's own face.  相似文献   
999.
Semantic representations of word meanings by the cerebral hemispheres   总被引:1,自引:0,他引:1  
Two priming experiments investigated kind and strength of semantic knowledge underlying known, frontier, and unknown low frequency words. Results from Experiment 1 suggest that known words reflect categorical knowledge, but frontier and unknown words reflect thematic knowledge. Thematic knowledge for frontier words appears to be stronger than that for unknown words. Experiment 2 entailed visual half-field presentation of targets. All facilitory effects were restricted to the lvf/RH, and inhibitory effects to the rvf/LH. Experiment 1 findings were mirrored by the RH. Thematic knowledge appears to precede categorical knowledge for the RH, but the opposite may be true of the LH. Results are also discussed in terms of the RH role in meaning acquisition and metacontrol.  相似文献   
1000.
The microstructures of 304 stainless steels with different amounts of nanocrystalline and microcrystalline austenite prepared by an aluminothermic reaction casting, without and with annealing at 1073?K for 8?h, have been investigated by X-ray diffraction, an electron probe micro-analyser, a transmission electron microscope and a scanning electron microscope. The steels, both without and with annealing, consisted of different dual nanocrystalline and microcrystalline austenite combinations and a little nanocrystalline δ ferrite, while the average grain size of the nanocrystalline austenite increased from 19 to 26?nm and volume fraction of the microcrystalline austenite increased from 17 to 30% after annealing. The tensile strength of the steel was dramatically increased from 500 to 1000?MPa and the tensile elongation ratio increased from 8 to 12% after annealing. However, the tensile strength was decreased to 600?MPa and the tensile elongation ratio increased from 12 to 22% after an annealing at 1273?K. The combination of dual nanocrystalline and microcrystalline austenite obtained after the annealing at 1073?K results in the best tensile properties.  相似文献   
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