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11.
Djerrad  Abderrahim  Fan  Feng  Zhi  Xu-dong  Wu  Qi-jian 《钢结构国际杂志》2020,20(1):156-174
International Journal of Steel Structures - The use of FRP composites as external confinement has recently become a very important system to consider when reinforcing concrete and steel structures....  相似文献   
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Using Monte Carlo simulations, we are studying the magnetic properties of Fe-doped CuO thin films. The total magnetizations and the susceptibilities are studied as a function of the effect doping, external magnetic field, and exchange coupling. The critical temperature is discussed as a function of the effect of iron concentration. On the other hand, we investigate the effect of increasing temperatures on the coercive field for a constant value of exchange coupling and a fixed concentration. The coercive magnetic field is found to decrease with increasing temperature values until reaching its null value. The effect of increasing the exchange coupling amount on the saturation magnetic field H s is illustrated. A linear growth of the saturation magnetic field is found as a function of the exchange coupling interaction. To complete this study, we presented and discussed the magnetic hysteresis cycle loops.  相似文献   
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Thermodynamic properties of the mixed aqueous electrolyte systems of the lithium and cesium chlorides and sodium and cesium chlorides have been studied by the hygrometric method at 298.15 K. The water activities of these systems were measured at total molalities from 0.3 mol kg−1 to saturation for different ionic strength fractions y of CsCl for the systems CsCl–LiCl(aq) and CsCl–NaCl(aq) with y=0.33, 0.50 and 0.67. The results allow the deduction of osmotic coefficients. The experimental results are compared with calculations made using the Zdanovskii–Stokes–Robinson (ZSR), Kusik and Meissner (KM), Robinson and Stokes (RS), Lietzke and Stoughton (LSII), Reilly, Wood and Robinson (RWR) rules, and the Pitzer model. From these measurements, the Pitzer mixing ionic parameters are determined and used to obtain the solute activity coefficients of the mixture for different ionic strength fractions y.  相似文献   
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In this paper, we introduce new sets of 2D and 3D rotation, scaling and translation invariants based on orthogonal radial Racah moments. We also provide theoretical mathematics to derive them. Thus, this work proposes in the first case a new 2D radial Racah moments based on polar representation of an object by one-dimensional orthogonal discrete Racah polynomials on non-uniform lattice, and a circular function. In the second case, we present new 3D radial Racah moments using a spherical representation of volumetric image by one-dimensional orthogonal discrete Racah polynomials and a spherical function. Further 2D and 3D invariants are extracted from the proposed 2D and 3D radial Racah moments respectively will appear in the third case. To validate the proposed approach, we have resolved three problems. The 2D/ 3D image reconstruction, the invariance of 2D/3D rotation, scaling and translation, and the pattern recognition. The result of experiments show that the Racah moments have done better than the Krawtchouk moments, with and without noise. Simultaneously, the mentioned reconstruction converges rapidly to the original image using 2D and 3D radial Racah moments, and the test 2D/3D images are clearly recognized from a set of images that are available in COIL-20 database for 2D image, and PSB database for 3D image.  相似文献   
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Real-time automated drone-based crack detection can be used for efficient building damage assessment. This paper proposes an automated real-time crack detection method based on a drone. Using a lightweight classification algorithm, a lightweight segmentation algorithm, a high-precision segmentation algorithm, and a crack width measurement algorithm, the cracks are classified, roughly segmented, finely segmented, and the maximum width is extracted. A crack information-assisted drone flight automatic control algorithm for automatic crack detection guides the drone toward the crack position. The effectiveness of the crack detection algorithm and the crack information-assisted drone flight automatic control algorithm was tested on two different datasets, a two-story building, and a 16-m-high shaking table test building. The results show that crack detection can be finished in real-time during the flight. Using the proposed method can significantly improve the MIoU of crack edge detection and the accuracy of maximum crack width measurement under the non-ideal shooting conditions of the actual inspection situation by automatically approaching the vicinity of the crack.  相似文献   
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This article presents a novel algorithm that accurately predicts market trends and identifies trading entry points for US 30-year Treasury bonds. The proposed method employs a hybrid approach, integrating a 1-dimensional convolutional neural network (1DCNN), long-short term memory (LSTM), and XGBoost algorithms. The 1DCNN is used to learn local and short-term patterns, while LSTM is employed to capture both short and long-term dependencies. Furthermore, we have implemented an algorithm that utilizes hull moving average (HMA) and simple moving average (SMA) crossover data to detect trading entry points and major trends in the market. The combination of the SMA–HMA crossover algorithm and predictions provided by the 1DCNN-BiLSTM-XGBoost algorithm yields exceptional results in terms of prediction accuracy and profitability. Additionally, these integrated techniques effectively filter out noise and mitigate false breakouts, which are often observed with US 30-year Treasury bonds. In the field of financial time series prediction, the effectiveness of 1DCNN and LSTM in identifying trading entry points and market perturbations has not been comprehensively studied. Therefore, our work fills this gap by demonstrating through experiments that the proposed 1DCNN-BiLSTM-XGBoost algorithm, in combination with moving average crossovers, effectively reduces noise and market perturbations. This leads to the precise identification of trading entry points and accurate recognition of trend signals for US 30-year Treasury bonds. We demonstrate through experiments that our proposed approach achieves an average root mean squared error of 0.0001 and an R-square value of 0.9999, highlighting its promise as a method for predicting market trends and trading entry points for US 30-year Treasury bonds.  相似文献   
19.
    
Vitis vinifera (L) crops, covers an area of about 54,000 ha corresponding to a production of 230,000 t of grapes, representing 5.5% of the national perennial corps. However, this plant is sensitive to various ravages and diseases, among others, the cryptogrammic by fungi. The degrading enzymes of the cell wall are among the factors of pathogenicity the more important than fungi use to colonize their host plants. In this study, the first step was devoted to the antioxidant activity and phenols composition (phenylalanine-ammonia-lyase [PAL], tyrosine-ammonia-lyase [TAL], flavonoids, and tannins) as well as high-performance liquid chromatography analysis in five vineyard leaves extract, which are “Superior, Early sweet and Flame” (Allochthonous), “Abbou and Adari” (endemic). In the second step, the lytic activities “pectinase, polygalacturonase, xylanase, mannanase, glucanase, and cellulase” were investigated among six epiphytic fungus to compare their hydrolytic aggressiveness. Subsequently, as a third part, phenols antifungal potency and Trichoderma biocontrol were displayed in the study. The phenolic compounds observed in the attributes leaves were different among varieties (p < .05), and show that the endemic variety “Abbou” leads the phytochemical amount, which has the highest quantities of PAL, and TAL, as well as the DPPH and FRAP antioxidant activity, while the introduced variety show a higher amount in total phenol and flavonoids. The polygalacturonase, mannanase, and pectinase activities are probably the main factors responsible for the aggressiveness of the studied fungus. Phenols potency showed a good mycelial inhibition with 82.09% as compared to the biocontrol (64.45%). Given the efficacy of the phytochemical control in this study, the phenols could be a part of integrated management strategies for sustainable control of vineyard disease.  相似文献   
20.
    
In this paper, a study of the effect of thin GaN interfacial layer (1 nm) on the electrical behavior of Au/n-GaAs structure is investigated in wide temperature range 100 to 400 K, using Silvaco-Atlas simulator. As a result, from I-V characteristics, the series resistance R s is increased with decreasing temperature for Au/GaN/n-GaAs structure, while it is remained almost constant for Au/n-GaAs structure. The saturation current I s is decreased with decreasing temperature for both structures. The ideality factor n is increased, and the barrier height is decreased when temperature decreases, with important variation for Au/GaN/n-GaAs structure. This abnormal behavior is due to the deviation of the dominant conduction mechanisms, from the thermionic emission TE current to the thermionic field emission TFE and the field emission FE. As well as, the Au/n-GaAs structure shows a homogeneous of barrier height, while it is inhomogeneous for Au/GaN/n-GaAs structure. In addition, from C-V characteristics, the potential diffusion V d and the barrier height are increased with decreasing temperature for both structures, conversely to those obtained from the TE theory. These results confirm the deviation of the TE current to the TFE and FE currents with decreasing temperature for the Au/n-GaAs and Au/GaN/n-GaAs Schottky diodes.  相似文献   
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