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41.
Statistical machine translation systems are usually trained on large amounts of bilingual text (used to learn a translation
model), and also large amounts of monolingual text in the target language (used to train a language model). In this article
we explore the use of semi-supervised model adaptation methods for the effective use of monolingual data from the source language
in order to improve translation quality. We propose several algorithms with this aim, and present the strengths and weaknesses
of each one. We present detailed experimental evaluations on the French–English EuroParl data set and on data from the NIST
Chinese–English large-data track. We show a significant improvement in translation quality on both tasks. 相似文献
42.
Educational research over the past three years has intensified such that the context of learning resources needs to be properly modeled. Many researchers have described and even mandated the use of ontologies in the research being conducted, yet the process of actually connecting one or more ontologies to a learning object has not been extensively discussed. This paper describes a practical model for associating multiple ontologies with learning objects while making full use of the IEEE LOM specification. The model categorizes these ontologies according to five major categories of context based on the most popular fields of study actively being pursued by the educational research community: Thematic context, Pedagogical context, Learner context, Organizational context, and Historical/Statistical context. 相似文献
43.
Gijsbert Erkens Jeroen Janssen 《International Journal of Computer-Supported Collaborative Learning》2008,3(4):447-470
Although protocol analysis can be an important tool for researchers to investigate the process of collaboration and communication,
the use of this method of analysis can be time consuming. Hence, an automatic coding procedure for coding dialogue acts was
developed. This procedure helps to determine the communicative function of messages in online discussions by recognizing discourse
markers and cue phrases in the utterances. Five main communicative functions are distinguished: argumentative, responsive, informative, elicitative, and imperative. A total of 29 different dialogue acts are specified and recognized automatically in collaboration protocols. The reliability
of the automatic coding procedure was determined by comparing automatically coded dialogue acts to hand-coded dialogue acts
by a human rater. The validity of the automatic coding procedure was examined using three different types of analyses. First,
an examination of group differences was used (dialogue acts used by female versus male students). Ideally, the coding procedure
should be able to distinguish between groups who are likely to communicate differently. Second, to examine the validity of
the automatic coding procedure through examination of experimental intervention, the results of the automatic coding procedure
of students, with access to a tool that visualizes the degree of participation of each student, were compared to students
who did not have access to this tool. Finally, the validity of the automatic coding procedure of dialogue acts was examined
using correlation analyses. Results of the automatic coding procedure of dialogue acts of utterances (form) were related to
results of a manual coding procedure of the collaborative activities to which the utterances refer (content). The analyses
presented in this paper indicate promising results concerning the reliability and validity of the automatic coding procedure
for dialogue acts. However, limitations of the procedure were also found and discussed. 相似文献
44.
Alexander Babich Konstantinos Mavrommatis Dieter Senk Heinrich Wilhelm Gudenau 《国际钢铁研究》2004,75(7):428-432
This contribution deals with advanced educational technologies needed to equip customers from higher education institutions, research and industry with efficient tools supporting their work and operating new skills‐training methods. The challenges are reducing the training costs, improving quality and increasing the number of graduates in engineering departments. The concept of a Virtual Lab based on the combination of various teaching methods and tools is presented. Principles of mathematisation in metallurgical education and training are discussed. An example of online course designed in the form of Virtual Lab is demonstrated. 相似文献
45.
Learning and memory of novel spatial configurations aids behaviors such as visual search through an implicit process called contextual cuing (M. M. Chun & Y. Jiang, 1998). The present study provides rigorous tests of the implicit nature of contextual cuing. Experiment 1 used a recognition test that closely matched the learning task, confirming that memory traces of predictive spatial context were not accessible to conscious retrieval. Experiment 2 gave explicit instructions to encode visual context during learning, but learning was not improved and conscious memory remained undetectable. Experiment 3 illustrates that memory traces for spatial context may persist for at least 1 week, suggesting a long-term component of contextual cuing. These experiments indicate that the learning and memory of spatial context in the contextual cuing task are indeed implicit. The results have implications for understanding the neural substrate of spatial contextual learning, which may depend on an intact medial temporal lobe system that includes the hippocampus (M. M. Chun & E. A. Phelps, 1999). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Children can express thoughts in gesture that they do not express in speech--they produce gesture-speech mismatches. Moreover, children who produce mismatches on a given task are particularly ready to learn that task. Gesture, then, is a tool that researchers can use to predict who will profit from instruction. But is gesture also useful to adults who must decide how to instruct a particular child? We asked 8 adults to instruct 38 third- and fourth-grade children individually in a math problem. We found that the adults offered more variable instruction to children who produced mismatches than to children who produced no mismatches--more different types of instructional strategies and more instructions that contained two different strategies, one in speech and the other in gesture. The children thus appeared to be shaping their own learning environments just by moving their hands. Gesture not only reflects a child's understanding but can play a role in eliciting input that could shape that understanding. As such, it may be part of the mechanism of cognitive change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
The role of words and gestures in guiding infants' inductive inferences about nonobvious properties was examined. One hundred seventy-two 14-month-olds and 22-month-olds were presented with novel target objects followed by test objects that varied in similarity to the target. Objects were introduced with a novel word or a novel gesture or with no label. When target and test objects were highly similar in shape, both 14- and 22-month-olds inferred that these objects shared a nonobvious property, regardless of whether the objects were labeled with a word or a gesture or with no label. When objects were labeled with the same word, both 14- and 22-month-olds generalized the nonobvious properties to objects that shared minimal perceptual similarity. Finally, when objects were labeled with the same gesture, 14-month-olds, but not 22-month-olds, generalized the nonobvious properties to objects that shared minimal perceptual similarity. These results indicate that 14-month-olds possess a more generalized symbolic system as they will rely on both words and gestures to guide their inferences. By 22-months of age, infants treat words as a privileged referential form when making inductive inferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Schulz Laura E.; Bonawitz Elizabeth Baraff; Griffiths Thomas L. 《Canadian Metallurgical Quarterly》2007,43(5):1124
Causal learning requires integrating constraints provided by domain-specific theories with domain-general statistical learning. In order to investigate the interaction between these factors, the authors presented preschoolers with stories pitting their existing theories against statistical evidence. Each child heard 2 stories in which 2 candidate causes co-occurred with an effect. Evidence was presented in the form: AB→E; CA→E; AD→E; and so forth. In 1 story, all variables came from the same domain; in the other, the recurring candidate cause, A, came from a different domain (A was a psychological cause of a biological effect). After receiving this statistical evidence, children were asked to identify the cause of the effect on a new trial. Consistent with the predictions of a Bayesian model, all children were more likely to identify A as the cause within domains than across domains. Whereas 3.5-year-olds learned only from the within-domain evidence, 4- and 5-year-olds learned from the cross-domain evidence and were able to transfer their new expectations about psychosomatic causality to a novel task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
In Part 1 of this two-part series, we introduced Katamic memory—a neural network architecture capable of robust sequence learning and recognition. In Part 2, we introduce the Blobs World taskjdomain for language learning and describe the DETE language learning system, which is composed of over 50 Katamic memory modules. DETE currently learns small subsets of English and Spanish via association with perceptual! motor inputs. In addition to Kaiamic memory, DETE employs several other novel features: (1) use of feature planes, to encode visual shapes, spatial relationships and the motions of objects, (2) phase-locking of neural firing, in order to represent focus of atention and to bind objects across multiple feature planes, and (3) a method for encoding temporal relationships, so that DETE can learn utterances involving the immediate past and future. We compare DETE to related models and discuss the implications of this approach for language-learning research. 相似文献
50.
Visually perceiving an action may activate corresponding motor programs. This automatic motor activation can occur both for higher level (i.e., the goal of an action) and for lower level (i.e., the specific effector with which it is executed) aspects of an action. The authors used a tool-use action paradigm to experimentally dissociate priming effects for observing the target, the movement, or the target-to-movement mapping of a tool-use action. In 3 experiments, participants took turns in acting, observing the tool-use action of another person in trial n-1, and executing an action in trial n. Trial transitions from n-1 to n were manipulated in 4 conditions with (a) mapping repeated and movement and target changed, (b) target repeated and movement and mapping changed, (c) movement repeated and target and mapping changed, or (d) all components repeated. Results indicate priming effects for repeating the target-to-movement mapping (i.e., the action rule) of a tool-use action and suggest that a rather abstract action schema is activated during action observation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献