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31.
The purpose of this paper is to investigate the physical mechanism of NROM memory erase. Three conduction mechanisms potentially responsible of NROM erase will be analyzed (tunneling and emission of electrons through both bottom and top oxide, tunneling and injection of holes over the bottom oxide barrier) by means of standard two-dimensional simulations and ad-hoc models reproducing hole and electron transport mechanisms across the oxide not included in standard device simulators. Hot-hole injection will be identified as the actual conduction mechanism of NROM erase, and two compact models capable to describe the main characteristics of NROM erase current will be developed.  相似文献   
32.
Formation of composition-modulated alloys by electrodeposition   总被引:1,自引:0,他引:1  
A method has been developed to produce composition-modulated alloys by electrodeposition. The method was demonstrated for the copper-nickel couple. Salts of the two component metals are dissolved in a common electrolyte and the potential is alternately pulsed for fixed durations between values above and below the reduction potential of the less noble component. Co-deposition of the nobler metal into the other metal layer is diminished by setting unfavourable diffusion conditions during the more cathodic pulse. Modulation was achieved down to 0.8 nm thick layers. The resulting composition-modulated alloys were analysed by Auger spectroscopy and X-ray diffraction.  相似文献   
33.
Acknowledgement (ACK) filtering has been proposed as a technique to alleviate the congestion at the input of a slow channel located on the reverse path of a TCP connection. Old ACKs waiting at the input of the slow channel are erased when new ACKs are to be queued. In the literature the case of one‐ACK per connection at a time has been studied. In this paper we show that this is too aggressive for short transfers where ACKs arrive in bursts due to the slow start phase, and where the TCP source needs to receive the maximum number of ACKs to increase fast its window. We study first static filtering where a certain ACK queue length is allowed. We show analytically how this length needs to be chosen. We present then some algorithms that adapt the filtering of ACKs as a function of the slow channel utilization rather than the ACK queue length. These algorithms provide a good compromise between reducing the ACK queueing delay and passing a large number of ACKs that guarantee a fast window increase. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
34.
35.
Network equilibrium models that have traditionally been used for transportation planning have penetrated in recent years to other scientific fields. These models have recently been introduced in the telecommunication networks literature, as well as in the field of game theory. Researchers in the latter fields are not always aware of the very rich literature on equilibrium models outside of their application area. On the other hand, researchers that have used network equilibrium models in transportation may not be aware of new application areas of their tools. The aim of this paper is to present some central research issues and tools in network equilibria and pricing that could bring closer the three mentioned research communities.  相似文献   
36.
Four experiments examined whether group formation and positive in-group regard require interaggregate comparison as the in-group-requires-an-out-group assumption of the metacontrast principle implies. The authors fostered novel social aggregates with or without a contrasting aggregate with which members could compare and varied intra-aggregate factors (interaction or interdependence). Regardless of whether interaggregate comparison was feasible, the intra-aggregate factors increased the perceived entitativity of the aggregate and positive regard toward the aggregate (i.e., social attraction and cooperation among members). Mediation analyses were consistent with the possibility that the intra-aggregate factors promoted entitativity, which in turn promoted in-group regard. These data suggest that group formation and in-group regard have intragroup origins and do not require comparison with a contrasting social aggregate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
The use of principal component analysis in preprocessing neural network input data is explored. Four preprocessing schemes are compared in an example problem, and the theoretical basis for the results are discussed. A preconditioning method for the principal components is introduced here, combining normalisation and improved conditioning. The techniques are applied to an object location problem in diffraction tomography. The spectral analysed scattered field from an irradiated object form the input to a Multilayer Perceptron neural network, trained by backpropagation to calculate the coordinates of the object's centre in 2D.Aspects of this work were presented at the NCAF Symposium, King's College London, 9 January 1992.  相似文献   
38.
The browning of green olives, which results from mechanical injury, was followed by measuring the reflectance from the fruit surface at 545 nm. The process is enzymic, apparently catalysed by catechol oxidase. It could not be prevented by inhibitors of the enzyme or by reducing agents, due to the impermeability of the whole fruit to these compounds. Dipping the fruit in 0.4 % NaOH prevented the formation of brown spots following mechanical injury.  相似文献   
39.
15 males (mean age 29.2 yrs) participated in an experiment to evaluate the polygraph in a real-life situation; 2 Ss had actually cheated on a test. All Ss went through a standard polygraph test using the control questions method. This procedure guarantees the objective identification of "liars" without jeopardizing the real-life appearance of the experimental situation. Each S was evaluated by 3 polygraphers: One had access to the polygraph charts only, one observed the S's behavior but not his charts, and a third had both kinds of information. The evaluations of all 3 polygraphers were compared with the criterion. Evaluations based on both behavior observation and physiological charts were superior to those based on either type of information alone. However, evaluations based on the physiological information alone were not superior to those based on the behavioral information alone. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
Creep tests were carried out on epoxy resin specimens at room temperature and at different high stress levels under tension, compression, and flexure. Compared with the behavior at constant strain rate (CSR) reported in Part I of this work, creep strain–time curves revealed a distinct delayed yielding region of constant minimum rate (secondary creep) followed by a post-yielding region of increasing slope (tertiary creep). In all cases, results indicate linearity between creep stress and log secondary creep rate, which is almost coincident with the corresponding relationship between yield stress and strain rate obtained in subsequent CSR loading cycles with the same specimens. The similarity in behavior under both the creep and CSR modes conforms to Eyring's theory of non-Newtonian viscous flow at high stress levels and low temperature. Theoretical analysis yields reasonable values of the activation volume, which is unaffected by the loading and test modes or by loading history, and could thus be regarded as an intrinsic parameter of the microstructure, inherently related to the viscoplastic process involved. The above considerations indicate a deviatoric stress-biased diffusional mechanism as the predominant factor in the yielding of an amorphous glassy epoxy system.  相似文献   
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