全文获取类型
收费全文 | 349篇 |
免费 | 9篇 |
专业分类
358篇 |
出版年
2021年 | 6篇 |
2019年 | 6篇 |
2018年 | 9篇 |
2017年 | 13篇 |
2016年 | 9篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 50篇 |
2012年 | 15篇 |
2011年 | 15篇 |
2010年 | 12篇 |
2009年 | 9篇 |
2008年 | 12篇 |
2007年 | 10篇 |
2006年 | 14篇 |
2005年 | 9篇 |
2004年 | 4篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 10篇 |
2000年 | 5篇 |
1999年 | 4篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 5篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1968年 | 4篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有358条查询结果,搜索用时 0 毫秒
21.
Vernon L. Quinsey 《Journal of the experimental analysis of behavior》1972,17(1):119-125
Hungry rats were allowed to lick an 8% sucrose solution and then one of four lick-shock contingency conditions was superimposed on the licking baseline. These conditions were: free-operant avoidance, free shock, punishment, and no shock. From highest to lowest response rates, the groups fell in the order-avoidance, no shock, free shock, and punishment. Lick rates adjusted rapidly to introduction and removal of the contingencies. Post-shock responding was lowest in the punishment condition and highest in the free shock condition. No method was found simultaneously to equate shock frequency and separate response rates for the three shock contingency conditions. Only small, or no, reductions in shock rate occurred over sessions under the free-operant avoidance schedule when the shock-shock interval was 10 sec but large reductions occurred when the shock-shock interval was reduced to either 1 or 2 sec. 相似文献
22.
23.
Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be affine covariant regions, that is, they will be invariant to affine transformation, being detected under different viewing conditions (view-point angle, rotation, scale, etc.). Monocular SLAM will be solved using the accurate parallel tracking and mapping (PTAM) framework by Klein and Murray in Proceedings of IEEE/ACM international symposium on mixed and augmented reality, 2007. 相似文献
24.
BCI (Brain-Computer Interface) is a system that allows interaction between the human brain and a computer. It is based on analyzing electroencephalographic signals (EEG) and processing them to generate control commands. The study analyzed the possible influence of psychological variables, such as the imaginative kinesthetic capacity and anxiety, in relation to performance in a BCI. All participants (4 male and 19 female students) completed the questionnaires and carried out a session of BCI to control their EEG signals in a virtual setting of a car along a straight road. The group was divided into two subgroups according to their EEG signals or differential responses obtained in the left-right discrimination. Study results showed no significant differences in cognitive variables of imagination or in anxiety. By comparing the degree of participants' BCI control, a new quantitative parameter for comparing performances and making decisions in signal processing was found. The findings, the ongoing research process to refine the control of a BCI, and the interaction of psychological and computer procedures are discussed. 相似文献
25.
Calderón-Garcidueñas L Engle R Mora-Tiscareño A Styner M Gómez-Garza G Zhu H Jewells V Torres-Jardón R Romero L Monroy-Acosta ME Bryant C González-González LO Medina-Cortina H D'Angiulli A 《Brain and cognition》2011,77(3):345-355
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH−) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH− - in right parietal and bilateral temporal areas. Both WMH− and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood. 相似文献
26.
Stephen A. Marshall Steven W. Evans Ricardo B. Eiraldi Stephen P. Becker Thomas J. Power 《Journal of abnormal child psychology》2014,42(1):77-90
Sluggish cognitive tempo (SCT) was originally identified as a construct that characterized the inattention problems of some children with attention deficit disorder (ADD). Research has indicated that using SCT symptoms to identify a subset of youth with attention-deficit/hyperactivity disorder, predominately inattentive type (ADHD-IT) may elucidate distinct patterns of impairment and thereby improve the external validity of ADHD subtypes. The objective of the current study was to investigate whether youth with clinically-assessed ADHD-IT and high levels of SCT exhibit unique social and academic impairments. In a clinic-referred sample of youth (N?=?209; 23 % female) aged 6 to 17 years, participants who met criteria for three different groups were identified: ADHD, Combined Type (ADHD-CT; n?=?80), ADHD-IT with low SCT symptoms (n?=?74), and ADHD-IT with high SCT symptoms (n?=?55). These groups were compared on indicators of social and academic functioning while considering the effects of co-occurring internalizing and disruptive behavior disorders. Youth with ADHD-IT high in SCT exhibited uniquely elevated withdrawal, as well as low leadership and low peer-directed relational and overt aggression, which were not accounted for by co-occurring disorders. This high-SCT group was also the only group to have more homework problems than the ADHD-CT group, but only when other disruptive behavior disorders were absent. The distinctiveness of the high-SCT group, which was primarily evident in social as opposed to academic functioning, provides partial support for the external validity and clinical utility of SCT. 相似文献
27.
Maria Emília Rodrigues de Oliveira Thais Gisele Cavallazzi Douglas Afonso Formolo Lucas D'Ávila de Castro Roseli Schmoeller Ricardo Guarnieri Marcelo Liborio Schwarzbold Alexandre Paim Diaz Alexandre Hohl Rui D. S. Prediger Maria Joana Mader Marcelo Neves Linhares Angelica Staniloiu Hans J. Markowitsch Roger Walz 《Journal of Neuropsychology》2014,8(1):125-139
28.
Ricardo Pagán Rodríguez Carlos Rivas Sánchez Carmen Ordóñez de Haro José Sánchez Maldonado 《Applied research in quality of life》2014,9(3):711-731
This study analyzes the differences in job satisfaction of older European people (aged 50-64), with or without disabilities, who are employed in either the public or the private sector. Using the data taken from the Survey of Health, Ageing and Retirement in Europe (SHARE) for the years 2004, 2007 and 2011, job satisfaction equations are estimated for workers from both the public and private sectors, with panel data techniques that include variables related to the worker's degree of disability (nondisabled, non-limited disabled, and limited disabled), among others. The results show that the disabled workers who are limited in their everyday activities are less satisfied in both the public and private sectors than those who are non-disabled and non-limited. In addition, the levels of job satisfaction for non-limited disabled people are higher than their non-disabled counterparts but only in the public sector. From a point of view of public policies, it is necessary to design and undertake measures and actions that would contribute to improving the levels of job satisfaction of older workers with disabilities, especially among those who are limited in their everyday activities. 相似文献
29.
Philosophia - The relation between conceptual analysis and empirical observations when ascribing or denying concepts and beliefs to non-human animals is not straightforward. In order to reflect on... 相似文献
30.
Aitana Fernández-Sogorb Cándido J. Inglés Ricardo Sanmartín Carolina Gonzálvez María Vicent y José Manuel García-Fernández 《International Journal of Clinical and Health Psychology》2018,18(3):264-272