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71.
72.
A ground-based experiment in passive microwave remote sensing of soil moisture was conducted in Huntsville, AL, from July 1-14, 1996. The goal of the experiment was to evaluate the overall performance of an empirically-based retrieval algorithm at S-band and L-band under a different set of conditions and to characterize the site-specific accuracy inherent within the technique. With high temporal frequency observations at S-band and L-band, the authors were able to observe large scale moisture changes following irrigation and rainfall events, as well as diurnal behavior of surface moisture among three plots, one bare, one covered with short grass and another covered with alfalfa. The L-band emitting depth was determined to be on the order of 0-3 or 0-5 cm below 0.30 cm3/cm3 with an indication that it is less at higher moisture values. The S-band emitting depth was not readily distinguishable from L-band. The uncertainty in remotely sensed soil moisture observations due to surface heterogeneity and temporal variability in variables and parameters was characterized by imposing random errors on the most sensitive variables and parameters and computing the confidence limits on the observations. Discrepancies between remotely sensed and gravimetric soil moisture estimates appear to be larger than those expected from errors in variable and parameter estimation. This would suggest that a vegetation correction procedure based on more dynamic modeling may be required to improve the accuracy of remotely sensed soil moisture  相似文献   
73.
The effect of high-density polyethylene (HDPE) on the textural features of experimental coke was investigated using polar- ized-light optical microscopy and wavelet-based image analysis. Metallurgical coke samples were prepared in a laboratory-scale furnace with 2.5%, 5.0%, 7.5%, 10.0%, and 12.5% HDPE by mass, and one sample was prepared by 100% coal. The amounts and distribution of textures (isotropic, mosaic and banded) and por~s were obtained. The calculations reveal that the addition of HDPE results in a decrease of mosaic texture and an increase of isotropic texture. Ethylene formed from the decomposition of HDPE is considered as a probable reason for the texture modifications. The approach used in this study can be applied to indirect evaluation for the reactivity and strength of coke.  相似文献   
74.
In this study, Chitosan/Al2O3/Fe3O4 core‐shell composite microsphere (CAMF) was used as an effective sorbent with high adsorption capacity for the removal of anionic azo dye model from aqueous solution. The obtained composite was characterized by XRD, SEM, EDX, and BET analysis. The results showed the high methyl orange (MO) adsorption in a wide pH range of 4–10 and the optimum adsorbent dosage was obtained 0.6 g L?1. It is indicated that the equilibrium data followed the Langmuir isotherm model and the adsorption kinetic was well fitted with pseudo‐second‐order kinetic model. Also, the adsorption kinetic was controlled by the film diffusion and intra‐particle diffusion, simultaneously. It is revealed that by increasing the particle size from <0.1 μm to ~0.4 μm, the adsorption capacity did not change, significantly. The adsorption capacity of MO on CAMF was predicted by multilayer perceptron (MLP) neural network at different initial MO concentration, in which the predictions of MLP model had very good agreement with experimental data. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43466.  相似文献   
75.
This paper presents an approach which enables surface modelling, mesh generation and the Finite Element (FE) analysis to be integrated together to simulate superplastic forming process for complex shaped components. Techniques have been developed to generate an FE mesh over non-four-sided surface areas, the boundaries of which are Bezier curves of arbitrary degree, using a consistent expression. Theoretical evidence is given to determine the number of Bezier triangular patches required for accurately re-constructing die surfaces within a commercial FE solver. The developed techniques have been successfully used in determining the process parameters for forming a 3D rectangular box.  相似文献   
76.
Journal of Materials Science: Materials in Electronics - Real-time interpretation and modification of information can impart revolutionary advancements in the evolution of the internet of things....  相似文献   
77.
Successful E-Business is based on seamless collaborative business processes. Each partner in the collaboration specifies its own rules and interaction preconditions. The verification of the compatibility of collaborative business processes, based on local and global views, is a complex task, which is critical for the success of the cooperation. The verification of process compatibility should be a key element in the design of new business alliances, which makes this verification essential in inter-organizational business process design. The advent of Web Services and Service Oriented Architectures stresses the need to solve complex business cooperations under the pressure of reduced costs and risks, combined with shorter time to market. At the same time, the message-based paradigm results in large and complex processes which makes the verification process quite hard.First the use of an atomic business activity based interaction paradigm is proposed to reduce the complexity of collaborative process models. Next, formal compatibility criteria for business processes are developed. The key construction is the notion of semantic compatibility, which can be used to assess the compatibility of the publicly exposed behavior (a.k.a. business interfaces) between business partners in joint business processes. The formal nature of this compatibility allows to give a precise indication of the degree of compatibility between cooperating business partners. It enables exhaustive lists of incompatible (i.e. unsupported scenarios) business cooperations, which is more comprehensive and complete than the typical compatible or incompatible answer to this question. Finally, complex multiple party interactions can be examined in terms of the safety of the interaction protocols.  相似文献   
78.
The first-order diffraction efficiency of a waveguide diffraction grating is maximized, for a wide range of grating periods, by optimization of the effective-index modulation profile. Three different values of effective-index modulation in the range of 0.02-0.11 are considered. The analysis is performed with the thin-grating-decomposition method. The results are verified by electromagnetic grating theory and applied to the construction of diffractive waveguide lenses with an improved overall efficiency. In the neighborhood of the optical axis, the optimized lens structure is a close approximation of a gradient-thickness Fresnel lens. Significant deviations from this shape appear when the local grating period reduces below ~ 15-25λ, where ~ is the wavelength of the guided mode. Near the edges of a high-numerical-aperture lens, where the local period is ~ 3-6λ, an approximate Bragg grating structure is obtained.  相似文献   
79.
In this paper, we consider the problem of multinomial classification of magnetoencephalography (MEG) data. The proposed method participated in the MEG mind reading competition of ICANN’11 conference, where the goal was to train a classifier for predicting the movie the test person was shown. Our approach was the best among ten submissions, reaching accuracy of 68 % of correct classifications in this five category problem. The method is based on a regularized logistic regression model, whose efficient feature selection is critical for cases with more measurements than samples. Moreover, a special attention is paid to the estimation of the generalization error in order to avoid overfitting to the training data. Here, in addition to describing our competition entry in detail, we report selected additional experiments, which question the usefulness of complex feature extraction procedures and the basic frequency decomposition of MEG signal for this application.  相似文献   
80.
This study focuses on analyzing the effects of several factors on the rate of decay of inherent viscosity (iv) during hydrolytic degradation. The analysis was made for oriented PLLA, 96L/4D PLA and 80L/20D,L PLA. The analyzed polymers were found to have identical rate of iv loss (P < 0.05), given that the materials have otherwise similar initial material properties. The effect of the post-processing residual monomer was dose dependent, i.e. the higher the monomer content the faster the degradation (P < 0.05). Samples with a smaller diameter (1.1 mm) were found to have a faster rate of iv loss than the samples with a larger diameter (4 mm) (P < 0.05). A multiple linear regression analysis was used to create a five-component linear model to predict changes in the materials’ inherent viscosity. This model yielded accurate predictions during the initial stages of the hydrolytic degradation process where the iv loss was virtually linear.  相似文献   
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