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91.
Network State Estimation and Prediction for Real-Time Traffic Management   总被引:1,自引:0,他引:1  
Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS) have the potential to contribute to the solution of the traffic congestion problem. DynaMIT is a real-time system that can be used to generate guidance for travelers. The main principle on which DynaMIT is based is that information should be consistent, and user optimal. Consistency implies that the traffic conditions experienced by the travelers are consistent with the condition assumed in generating the guidance. To generate consistent user optimal information, DynaMIT performs two main functions: state estimation and prediction. A demand simulator and a supply simulator interact to perform these tasks. A case study demonstrates the value of the system.  相似文献   
92.
We examined whether heart rate (HR) could be used to estimate energy expenditure (EE) in cattle. Six Hereford heifers (345 +/- 10.8 kg BW) 12 mo of age were implanted with HR radio transmitters and maintained in individual pens under the following treatments: 1) shade or sun exposure, 2) high- or low-energy diet, and 3) feeding in morning or afternoon. The HR of animals was measured every .5 h during 3 mo; measurements of oxygen consumption and HR were made simultaneously in the morning and in the afternoon while animals were resting and exercising. Average daily HR (52 +/- 4 beats/min) and average daily EE (380 +/- 9 kJ/kg(.75)) in animals on the low-energy diet were less than values in animals on the high-energy diet (94 +/- 4 beats/min and 653 +/- 9 kJ/ kg(.75), respectively). For each animal and within each diet, linear regressions best described the relationship between HR and EE in resting animals, whereas quadratic regressions best described this relationship for exercising animals. The quadratic equation for the exercising animals could also be used for resting animals. In addition, a constant value of EE per heart beat (EE pulse) for each individual resting animal was found and gave accurate estimations. This method was convenient because 1) no exercise equipment was needed to generate the regression equations and 2) EE pulse was less affected by diet than was EE estimated by regression equations. We conclude that HR, a relatively easy measurement, can be useful and accurate in estimating EE. To increase the accuracy of the estimation of EE by HR, the relationship of HR to EE should be established for each animal. In addition, the nutritional regimen for the animal in which EE is estimated should be used for the animal in establishing the relationship.  相似文献   
93.
Nerve growth conduits are designed to support and promote axon regeneration following nerve injuries. Multifunctionalized conduits with combined physical and chemical cues, are a promising avenue aimed at overcoming current therapeutic barriers. However, the efficacious assembly of conduits that promote neuronal growth remains a challenge. Here, a biomimetic regenerative gel is developed, that integrates physical and chemical cues in a biocompatible “one pot reaction” strategy. The collagen gel is enriched with magnetic nanoparticles coated with nerve growth factor (NGF). Then, through a remote magnetic actuation, highly aligned fibrillar gel structure embedded with anisotropically distributed coated nanoparticles, combining multiple regenerating strategies, is obtained. The effects of the multifunctional gels are examined in vitro, and in vivo in a 10-mm rat sciatic nerve injury model. The magneto-based therapeutic conduits demonstrate oriented and directed axonal growth, and improve nerve regeneration in vivo. The study of multifunctional guidance scaffolds that can be implemented efficiently and remotely provides the foundation to a novel therapeutic approach to overcome current medical obstacles for nerve injuries.  相似文献   
94.
Accelerated life testing for distributions with hazard rate functions of the form r(t) = Ag(t) + Bh(t) are considered. Let V 1, …, V k be stress levels larger than V 0—the stress level under normal conditions [V 0 > 0]—and let a(v) be a nondecreasing function on (0, ∞). We discuss a generalization of the common accelerated models (the power rule model and the Arrhenius model) by assuming that the hazard rate under the stress level V, is of the form (a(V t )) P (Ag(t) + Bh(t)). The maximum likelihood estimators of A, B and P for complete and censored samples are studied. The estimation procedure reduces to a solution of one equation with one unknown parameter. The estimation procedure under the assumption of aging is also described. The asymptotic variance-covariance matrix is given.  相似文献   
95.
This work presents the derivation of the exact dynamic stiffness matrix for a high‐order beam element. The terms are found directly from the solutions of the differential equations that describe the deformations of the cross‐section according to the high‐order theory, which include cubic variation of the axial displacements over the cross‐section of the beam. The model has six degrees of freedom at the two ends, one transverse displacement and two rotations, and the end forces are a shear force and two end moments. Using the dynamic stiffness matrix exact vibration frequencies for beams with various combinations of boundary conditions are tabulated and compared with results from the Bernoulli–Euler and Timoshenko beam models. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
96.
This communication is a commentary on William W. Meissner's presentation (see record 2006-20697-003) of a patient who chronically came late for sessions. The time duration of analytic work-relatively restricted per hour yet potentially limitless in overall duration-represents an existential paradox that is fundamental to the basic representational qualities of mental experience, and inherent in a mute way in the analytic frame. It is to be expected that the latent temporal elements of the patient's conflicts will inevitably challenge this aspect of the frame, subtly coercing patient and analyst to recreate these novel dimensions. If the analyst is too cautious regarding the inevitability of countertransference reactions to such a patient, important developmental opportunities may be missed. I suspect that the chronic lateness and absence that characterized the work with this patient screened an early, nonmentalized trauma that had torn a hole in the foundations of the patient's sense of time, and was inadvertently expressed by Meissner in an entirely atypical manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
Changes in the principal’s role, resulting from the computerization of a high-school’s instruction-administration subsystem (i.e. a significant technological change), occurred in six major categories: accountability, instruction evaluation, supervision, feedback, frequency of meetings, and shared decision-making. The principal’s interrelations with department heads, homeroom teachers and teachers, tightened significantly. The principal’s interrelations with the school computer administrator (a new role created as a result of the introduction of a school management information system), were found to be tight and on a daily basis. The results of this research might have significant theoretical and practical implications. They should be related to SMIS impact on schooling in general and on the principal’s role in particular.  相似文献   
98.
99.
This study compared memory for words and the font in which they appeared (or the voice speaking them) in young and old participants, to explore whether age-related differences in episodic word memory are due to age-related differences in memory for perceptual–contextual information. In each of 3 experiments, young and older participants were presented with words to learn. The words were presented in either 1 of 2 font types, or in 1 of 2 male voices, and participants paid attention either to the fonts or voices or to the meaning of the words. Participants were then tested on both word and font or voice memory. Results showed that younger participants had better explicit memory for font and voice memory and for the words themselves but that older participants benefited at least as much as younger people when perceptual characteristics of the words were reinstated. There was no evidence of an age-related impairment in the encoding of perceptual–contextual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
This study further tested an associative-deficit hypothesis (ADH; M. Naveh-Benjamin, 2000), which attributes a substantial part of older adults' deficient episodic memory performance to their difficulty in merging unrelated attributes-units of an episode into a cohesive unit. First, the results of 2 experiments replicate those observed by M. Naveh-Benjamin (2000) showing that older adults are particularly deficient in memory tests requiring associations. Second, the results extend the type of stimuli (pictures) under which older adults show this associative deficit. Third, the results support an ADH in that older adults show less of an associative deficit when the components of the episodes used are already connected in memory, thereby facilitating their encoding and retrieval. Finally, a group of younger adults who encoded the information under divided-attention conditions did not show this associative deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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