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1.
This letter presents a new polarizer which has a simple comb structure inside a circular waveguide. The electrical performance of the proposed comb polarizer is optimized by a circular waveguide radius and by the physical parameters of the comb plates. This polarizer is suitable for providing good performance in millimeter‐band application because of its simple structure and low fabrication cost. In our experiments the dual‐band comb polarizer designed in band 1(K) and band 2(Ka) showed good electrical performance without any tuning elements. 相似文献
2.
We present a high speed optical profiler (HSOP) using frequency-scanning lasers for three-dimensional profile measurements of microscopic structures. To improve upon previous techniques for implementing the HSOP, we developed frequency-scanning lasers and a compact microscopic interferometer. The controller of the HSOP was also modified to generate proper phase-shifting steps. For measurements of step height specimens, the HSOP showed results comparable with a commercial optical profiler, even with much higher measurement speeds (up to 30 Hz). The typical repeatability of step height measurement was less than 1 nm. We also present measurements of microscopic structures to verify the HSOP's ability to perform high speed inline inspection for the semiconductor and flat-panel display industries. 相似文献
3.
Conventional clinical decision support systems are generally based on a single classifier or a simple combination of these models, showing moderate performance. In this paper, we propose a classifier ensemble-based method for supporting the diagnosis of cardiovascular disease (CVD) based on aptamer chips. This AptaCDSS-E system overcomes conventional performance limitations by utilizing ensembles of different classifiers. Recent surveys show that CVD is one of the leading causes of death and that significant life savings can be achieved if precise diagnosis can be made. For CVD diagnosis, our system combines a set of four different classifiers with ensembles. Support vector machines and neural networks are adopted as base classifiers. Decision trees and Bayesian networks are also adopted to augment the system. Four aptamer-based biochip data sets including CVD data containing 66 samples were used to train and test the system. Three other supplementary data sets are used to alleviate data insufficiency. We investigated the effectiveness of the ensemble-based system with several different aggregation approaches by comparing the results with single classifier-based models. The prediction performance of the AptaCDSS-E system was assessed with a cross-validation test. The experimental results show that our system achieves high diagnosis accuracy (>94%) and comparably small prediction difference intervals (<6%), proving its usefulness in the clinical decision process of disease diagnosis. Additionally, 10 possible biomarkers are found for further investigation. 相似文献
4.
The polarization properties of solid-state cube-corner retroreflectors, which are uncoated glass or metal-coated glass on the reflecting surfaces, are examined analytically and compared. Experimental verifications are presented for the case of linearly polarized incident light. When the uncoated cube-corner is used in a heterodyne interferometer, the polarization properties reveal that the axial orientation of the corner reflector has an effect on the strength of the beat signal and the nonlinearity error. A theoretical analysis of the effect is presented together with experimental results. 相似文献
5.
Throughout this study on information processing using an artificial neural network (ANN) and chaos we are attempting to devise
a memory model that resembles human behavioral characteristics. For that purpose we construct a framework of the macroscopic
model of the responding process in biological systems. Incoming stimuli are applied to the sensory receptors and preprocessed.
A pattern-matching block allows one of the chaotic memories to find a feasible response in an associative way. After the chaotic
memory is stabilized on one of the stable equilibrium points or limit cycles, its performance is evaluated. Since chaotic
memory and the performance evaluation block form a feedback loop, they can handle features of the information blocks and store
newly updated information blocks. Two kinds of chaotic memories are established in this paper: one is a 1-D map in which many
information blocks can be stored as unstable periodic orbits, and the other is the famous Lozi attractor with rich dynamics.
Simulations are performed for the mobile robot navigation problem in each case.
This work was presented, in part, at the Second International Symposium on Artificial Life and Robotics, Oita, Japan, February
18–20, 1997 相似文献
6.
Behaviormetrika - In the original publication of the article, Appendix A was published incorrectly. 相似文献
7.
This paper presents a wavelet-based texture segmentation method using multilayer perceptron (MLP) networks and Markov random
fields (MRF) in a multi-scale Bayesian framework. Inputs and outputs of MLP networks are constructed to estimate a posterior
probability. The multi-scale features produced by multi-level wavelet decompositions of textured images are classified at
each scale by maximum a posterior (MAP) classification and the posterior probabilities from MLP networks. An MRF model is
used in order to model the prior distribution of each texture class, and a factor, which fuses the classification information
through scales and acts as a guide for the labeling decision, is incorporated into the MAP classification of each scale. By
fusing the multi-scale MAP classifications sequentially from coarse to fine scales, our proposed method gets the final and
improved segmentation result at the finest scale. In this fusion process, the MRF model serves as the smoothness constraint
and the Gibbs sampler acts as the MAP classifier. Our texture segmentation method was applied to segmentation of gray-level
textured images. The proposed segmentation method shows better performance than texture segmentation using the hidden Markov
trees (HMT) model and the HMTseg algorithm, which is a multi-scale Bayesian image segmentation algorithm. 相似文献
8.
We prepared cathodes with various types of activated carbon and measured the cathodes’ electrochemical performance according to the kind of activated carbon. Activated carbon supplies airflow channels and reaction sites in the cathode of zinc air batteries. When we use activated carbon with a high specific surface area as the cathode's catalyst substrate, we expect high electrochemical performance because this type of carbon provides more air flow channels and reaction sites.We focused on investigating the relationship between the cathode's pore structure and its electrochemical characterizations. We also studied the effects of the various activated carbon materials on the zinc air batteries’ performance. Increasing the macropores or mesopores in the activated carbon resulted in achieving more power from the battery. 相似文献
9.
The effects of residual polymerization solvent on the physical properties of poly(2‐cyano‐p‐phenylene terephthalamide) 下载免费PDF全文
Poly(2‐cyano‐p‐phenylene terephthalamide) (CY‐PPTA) was obtained by the polycondensation of terephthaloyl dichloride and 2‐cyano‐p‐phenylene diamine in the mixture of N‐methyl‐2‐pyrrolidone (NMP) and calcium chloride (CaCl2). Washing the polymerized product with water and drying at the elevated temperature inevitably left a small amount of polymerization residues which could be eliminated only by additional washing with acetone. The thermogravimetric and 1H‐/13C‐NMR analyses revealed that the residues were largely composed of NMP which existed as a complex with the polymer. The complex was broken up between 200 and 300 °C and evolved 5 wt % of gaseous products, which had an adverse effect on the physical properties of as‐spun CY‐PPTA fibers obtained by dry jet‐wet spinning. The heat treatment of the as‐spun fibers including residual NMP exhibited some porous morphology on the fiber surface due to the evolved gases. However, the existence of the residual NMP had little effect on the intrinsic viscosity and liquid crystalline phase behavior of the polymer. Both rheological and optical properties exhibited the critical concentration at 3 wt % with the clear schlieren texture of nematic liquid crystalline phase. The inclusion of residual NMP decreased dynamic viscosity and yield stress. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43672. 相似文献
10.
Yeonjung Han Yonggun Park Jun-Ho Park Sang-Yun Yang Chang-Deuk Eom 《Drying Technology》2016,34(13):1613-1620
This work focused on the shrinkage and drying stress of red pine (Pinus densiflora) wood during kiln drying and investigated transverse shrinkage and moisture changes in thin specimens using digital image analysis and near-infrared spectroscopy, respectively. The effect of specimen thickness, which ranged from 1 to 10?mm on shrinkage, was analyzed under drying conditions with restrained stresses. The shrinkage due to moisture content was presented in the form of an exponential function and a linear function above and below the fiber saturation point, respectively. A shorter existence of the moisture gradient increased the transverse shrinkage. The tangential and radial shrinkage at the tissue level in 30-µm (longitudinal) thick slices was measured and compared with the shrinkage of above specimens with difference thicknesses. The transverse shrinkage of 1-mm-thick specimen is similar to the shrinkage measured using 30-µm-thick slice. 相似文献