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861.
This paper reports on the research activities performed by the Pictorial Computing Laboratory at the University of Rome, La Sapienza, during the last 5 years. Such work, essentially is based on the study of humancomputer interaction, spans from metamodels of interaction down to prototypes of interactive systems for both synchronous multimedia communication and groupwork, annotation systems for web pages, also encompassing theoretical and practical issues of visual languages and environments also including pattern recognition algorithms. Some applications are also considered like e-learning and collaborative work.  相似文献   
862.
863.
In the present report, we describe a new dynamic field theory that captures the dynamics of visuo-spatial cognition. This theory grew out of the dynamic systems approach to motor control and development, and is grounded in neural principles. The initial application of dynamic field theory to issues in visuo-spatial cognition extended concepts of the motor approach to decision making in a sensori-motor context, and, more recently, to the dynamics of spatial cognition. Here we extend these concepts still further to address topics in visual cognition, including visual working memory for non-spatial object properties, the processes that underlie change detection, and the ‘binding problem’ in vision. In each case, we demonstrate that the general principles of the dynamic field approach can unify findings in the literature and generate novel predictions. We contend that the application of these concepts to visual cognition avoids the pitfalls of reductionist approaches in cognitive science, and points toward a formal integration of brains, bodies, and behavior.  相似文献   
864.
The live outdoor webcam seems inseparable from the mid-1990s’ popular proliferation of the Internet. Combining a well-known medium, i.e. the photograph, with a new one, i.e. the Internet, the live outdoor webcam seems in the rear-view mirror to have contributed significantly to the popular perception of the Internet as a globally distended and thus “geographical” medium. Moreover, due to its role in the NASA Triana mission, the never-realised flagship of the Clinton–Gore administration’s Digital Earth project, the live webcam seemed to play an important part in the construction of what leading geographers coined a “virtual geography”—the geography of the Internet, and the networked geography—that sought to establish itself as a new field of study during the late 1990s. In order to substantiate for this interpretation, I would like in the first part of this article to identify a number of basic characteristics of the outdoor webcam and, in the second, to analyse and discuss two papers written by leading scholars in the field; papers which have been important in the assessment of the impact of the Internet and geographical information systems (GIS) before the scientific community as well as policy makers within technological innovation and the public sector.
Troels Degn JohanssonEmail:
  相似文献   
865.
ABSTRACT— Evidence from longitudinal, experimental, and neuroimaging studies converge to indicate that psychological functions other than episodic memory are affected very early in the course of Alzheimer's disease and, indeed, may predate or influence the apparent memory deficits. Changes in personality and difficulty in executive function, especially in terms of attentional and inhibitory control, are especially prominent. Deficits in other types of memory (i.e., semantic memory, conditioning) can also be detected in the early stages of the disease. It is time to update existing diagnostic criteria for this form of dementia in terms of current knowledge of multiple and interacting brain systems.  相似文献   
866.
The three bases for the enthymeme: A dialogical theory   总被引:1,自引:0,他引:1  
In traditional logic, an enthymeme is said to be an argument, or chain of argumentation, with one or more missing (implicit) premises or conclusions. In this paper a new theory of enthymemes, based on recent developments in argumentation technology including argumentation schemes, argument visualization tools and formal dialogue systems, is put forward. The dialogical theory hypothesizes three bases for the enthymeme in a formal dialogue system CBVK: (1) the participants' commitment sets, (2) sets of argumentation schemes (especially including presumptive schemes) shared by both participants, and (3) a set of propositions representing common knowledge shared by both participants. The formal dialogue system CBVK is the backbone of the theory of enthymemes into which these three components are built. Three examples of enthymemes of a kind commonly found in everyday conversational argumentation are used to show how the theory applies.  相似文献   
867.
Guy Dove 《Cognition》2009,110(3):412-431
Recent evidence from cognitive neuroscience suggests that certain cognitive processes employ perceptual representations. Inspired by this evidence, a few researchers have proposed that cognition is inherently perceptual. They have developed an innovative theoretical approach that rests on the notion of perceptual simulation and marshaled several general arguments supporting the centrality of perceptual representations to concepts. In this article, I identify a number of weaknesses in these arguments and defend a multiple semantic code approach that posits both perceptual and non-perceptual representations.  相似文献   
868.
Unmanned systems in military applications will often play a role in determining the success or failure of combat missions and thus in determining who lives and dies in times of war. Designers of UMS must therefore consider ethical, as well as operational, requirements and limits when developing UMS. I group the ethical issues involved in UMS design under two broad headings, Building Safe Systems and Designing for the Law of Armed Conflict, and identify and discuss a number of issues under each of these headings. As well as identifying issues, I offer some analysis of their implications and how they might be addressed.
Robert SparrowEmail:
  相似文献   
869.
The social neuroscience of child and adolescent depression is inherently multidisciplinary. Depressive disorders beginning early in life can have serious developmental and functional consequences. Psychopathology research has described depression's defining clinical and contextual features, and intervention research has characterized its response to treatment and prevention programs. Neuroendocrine, electrophysiological, and neuroimaging studies have identified core neurobiological aspects of early-onset mood disorders. These areas are reviewed using a developmental social neuroscience perspective for integrating disparate observations. The paper introduces a dynamic adaptive systems framework, and it discusses hedonic capacity, stress sensitivity, ruminative self-focus, and attentional impairments as fundamental components of mood disorders.  相似文献   
870.
Chaos-related obstructions to predictability have been used to challenge accounts of theory validation based on the agreement between theoretical predictions and experimental data (Rueger & Sharp, 1996. The British Journal for the Philosophy of Science, 47, 93–112; Koperski, 1998. Philosophy of Science, 40, 194–212). These challenges are incomplete in two respects: (a) they do not show that chaotic regimes are unpredictable in principle (i.e., with unbounded resources) and, as a result, that there is something conceptually wrong with idealized expectations of correct predictions from acceptable theories, and (b) they do not explore whether chaos-induced predictive failures of deterministic models can be remedied by stochastic modeling. In this paper we appeal to an asymptotic analysis of state space trajectories and their numerical approximations to show that chaotic regimes are deterministically unpredictable even with unbounded resources. Additionally, we explain why stochastic models of chaotic systems, while predictively successful in some cases, are in general predictively as limited as deterministic ones. We conclude by suggesting that the way in which scientists deal with such principled obstructions to predictability calls for a more comprehensive approach to theory validation, on which experimental testing is augmented by a multifaceted mathematical analysis of theoretical models, capable of identifying chaos-related predictive failures as due to principled limitations which the world itself imposes on any less-than-omniscient epistemic access to some natural systems. We give special thanks to two anonymous reviewers for their helpful comments that have substantially contributed to the final version of this paper  相似文献   
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