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The present investigations were designed to determine the impact of picking dates on seed germination, 100 seed weight and various fiber parameters. Two genotypes FH-113 and FH-114 were evaluated under early and normal sowing. Nine and six pickings were taken under early and normal conditions, respectively. The results revealed significant variation in both the years for fiber traits but for seed germination, the results were non-significant and for seed weight remained significant under both sowing times, respectively. For picking time the estimates were significant under both sowing times thus exhibiting the major role of picking time in this experiment. For germination percentage, the results were variable for both the genotypes. For genotype FH-113, germination remained above 60% during 1st pick and for 5th, 6th, and 7th pick, the germination rates were higher and nearing almost 70%. For 2nd genotype, the germination remained below 50% from pick-1 to pick-4 and above 50% in pick 5 and 8 but for all other pickings the values remained in the range 45–50%. Under normal sowing both genotypes exhibited germination percentage near 60% at 1st pick but for 2nd and 3rd pick, the germination rate remained between 45% and 50%. Regarding correlation studies among the studied traits germination % had positive and highly significant correlation with 100 seed weight under both sowing times. Fiber fineness and strength had strong and highly significant correlation with fiber maturity under both conditions. The results from this study revealed that pickings during favorable conditions produce better quality and germination.  相似文献   
74.
A computer program to predict the performance of local area networks based on an Ethernet or other medium is described. The effects of bursty traffic are modeled as packet streams which are initially bulk Poisson, but whose clusters spread apart as they propagate through the network. It is shown by example that performance predictions using more conventional Poisson assumptions tend to be optimistic, often extremely so. The program presents a friendly, dialogue-oriented user interface, including a library of rather sophisticated transaction types for network loading. A simulator is included in the program to validate its analytical approximations, and two example simulations are presented. Although approximation errors can be large in highly bursty situations, these errors appear to be much less than those which would be obtained by treating bursty traffic as if it were Poisson.  相似文献   
75.

Since powerful editing software is easily accessible, manipulation on images is expedient and easy without leaving any noticeable evidences. Hence, it turns out to be a challenging chore to authenticate the genuineness of images as it is impossible for human’s naked eye to distinguish between the tampered image and actual image. Among the most common methods extensively used to copy and paste regions within the same image in tampering image is the copy-move method. Discrete Cosine Transform (DCT) has the ability to detect tampered regions accurately. Nevertheless, in terms of precision (FP) and recall (FN), the block size of overlapping block influenced the performance. In this paper, the researchers implemented the copy-move image forgery detection using DCT coefficient. Firstly, by using the standard image conversion technique, RGB image is transformed into grayscale image. Consequently, grayscale image is segregated into overlying blocks of m × m pixels, m = 4.8. 2D DCT coefficients are calculated and reposition into a feature vector using zig-zag scanning in every block. Eventually, lexicographic sort is used to sort the feature vectors. Finally, the duplicated block is located by the Euclidean Distance. In order to gauge the performance of the copy-move detection techniques with various block sizes with respect to accuracy and storage, threshold D_similar = 0.1 and distance threshold (N)_d = 100 are used to implement the 10 input images in order. Consequently, 4 × 4 overlying block size had high false positive thus decreased the accuracy of forged detection in terms of accuracy. However, 8 × 8 overlying block accomplished more accurately for forged detection in terms of precision and recall as compared to 4 × 4 overlying block. In a nutshell, the result of the accuracy performance of different overlying block size are influenced by the diverse size of forged area, distance between two forged areas and threshold value used for the research.

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76.
This study investigates the extrusion-spheronization performance of some mixtures of co-processed κ-carrageenan and pectin (as excipient), and sodium starch glycolate (as superdisintegrant). Attention is focused with an objective to improve the mechanical stability and the dissolution rate of poorly soluble domperidone (as a model drug). Initially, co-processed κ-carrageenan-pectin excipient is prepared with different ratios of κ-carrageenan and pectin. Different marketed brands of κ-carrageenan (Gelcarin, Aquagel and Eugel) were employed and dried by solvent evaporation method. Further characterization was carried out by SEM, XRD and FTIR analysis. Pellets were prepared using extrusion-spheronization technique. Pellets were evaluated for flow properties, particle size, sphericity, tensile strength, friability, disintegration time and in-vitro drug release studies. Solid-state characterization of pellets was also done by FTIR, DSC and SEM analysis. The mechanical stability and dissolution rate of prepared pellets were found to be dependent on the concentration of pectin and type of κ-carrageenan employed in the fabrication of pellets. The pellets made with a high proportion of Eugel showed a very high dissolution rate of domperidone and undergo rapid disintegration validating co-processed k-carrageenan-pectin as a promising pelletizing aid for immediate-release pharmaceutical formulations.  相似文献   
77.
This article proposes an ultra‐wideband coplanar strips (CPS) rectangular spiral antenna that is fed by coplanar waveguide (CPW). The CPS is formed by gradually reducing the width of the CPW ground planes without the need of a balun. The antenna operates in the frequency band (3.5‐10.6 GHz) and has miniaturized size of 50 × 40 × 0.508 mm on a Rogers RO4003C substrate. The CPS spiral is terminated with a 100 Ω chip resistor for matching. A parametric study was performed to choose the CPS spiral dimensions. A good agreement is found between simulations and measurements in the radiation pattern and the return loss which was found to be better than 10 dB over the band. The measured peak gain ranges between 1 and 4.7 dBi.  相似文献   
78.
Totally six dinuclear complexes of Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) of calix[4]arene derivatized with two pendants possessing terminal –COOH functions at two of its alternate phenolic –OH groups were synthesized for the first time and were well characterized.  相似文献   
79.
We present an extensive study of the magnetic properties of a novel La0.5Ba0.5MnO3 perovskite material prepared by the hydrothermal method. The explored sample was structurally studied by the x-ray diffraction (XRD) method which confirms the formation of a pure cubic phase of a perovskite structure with Pm3m space group. The magnetic properties were probed by employing temperature M (T) and external magnetic field M (μoH) dependence of magnetization measurements. A magnetic phase transition from ferromagnetic to paramagnetic phase occurs at 339 K in this sample. The maximum magnetic entropy change (\(\left | {{\Delta } S}_{M}^{\max } \right |\)) took a value of 1.4 J kg??1 K??1 at the applied magnetic field of 4.0 T for the explored sample and has also been found to occur at Curie temperature (TC). This large entropy change might be instigated from the abrupt reduction of magnetization at TC. The magnetocaloric effect (MCE) is maximum at TC as represented by M (μoH) isotherms. The relative cooling power (RCP) is 243.2 J kg??1 at μoH =?4.0 T. Moreover, the critical properties near TC have been probed from magnetic data. The critical exponents δ, β, and γ with values 3.82, 0.42, and 1.2 are close to the values predicted by the 3D Ising model. Additionally, the authenticity of the critical exponents has been confirmed by the scaling equation of state and all data fall on two separate branches, one for T < TC and the other for T > TC, signifying that the critical exponents obtained in this work are accurate.  相似文献   
80.
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