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21.
This study describes the development process of Kor-Factor, which is a novel composite evaluation index that was developed to promote Korean domestic academic journals. As more data accumulate, the Kor-Factor’s optimization process was modified in an attempt to address possible drawbacks of the original form; the result is presented in this study. This study compares Kor-Factor with the Impact Factor, which is the most well-known single element evaluation index. We found that Kor-Factor demonstrates a better power of differentiation and a greater capacity to reflect the reputability of key journals. The modified Kor-Factor, which has been developed through an optimization process, reveals a greater power of differentiation than the original Kor-Factor; however, the modified version has less capacity to reflect reputability. The evaluation elements of the modified Kor-Factor are better and are more evenly reflected on the index value than those of the original version. Finally, we propose the establishment of an appropriate data measurement period for the actual application of the index. 相似文献
22.
Zafer Odabaş İmran Koç Ahmet Altındal Ali Rıza Özkaya Bekir Salih Özer Bekaroğlu 《Synthetic Metals》2010,160(9-10):967-977
The new mono-nuclear FeII 2 and ball-type homo-dinuclear FeII–FeII 3 phthalocyanines have been synthesized from the corresponding 4,4′-(1a,8b-dihydronaphtho[b]naphthofuro[3,2-d]-furan-7,10-diyl)bis(oxy)diphthalonitrile 1 while ball-type hetero-dinuclear FeII–CoII phthalocyanine 4 was synthesized from 2. The compounds have been characterized by elemental analysis, UV–vis, IR and MALDI-TOF-mass spectroscopies. The redox behaviours of the complexes were identified by controlled-potential coulometry, cyclic voltammetry and differential pulse voltammetry measurements on Pt in dimethylsulfoxide containing tetrabutylammonium perchlorate. The assignments of the redox processes and the understanding of the interactions between the metal phthalocyanine units in 3 and 4 were achieved by the combined evaluation of the voltammetric and in situ spectroelectrochemical outcomes. Complex 3 showed ring-based mixed-valence behaviour as a result of the considerable interaction between the phthalocyanine rings. On the other hand, the interactions between the two metal phthalocyanine units of 4 were found to be much weaker than those in 3. The potential application of molecular organic semiconductors needs the control adjustment of conductivity. Ac and dc conductivity measurements were performed with the applied external electric filed. At high frequency, the conduction follows the universal power law and conduction mechanism can be explained by classical hopping barriers mechanism for the system. 相似文献
23.
<正>This paper presents an image resolution enhancement algorithm using spatially invariant point spread function.Point spread function is used to constrain the solution space.This parameter is computed at each iteration step using partially restored image at each iteration,and High pass filter is used to impose the degree of edge smoothness on the solution.The resulting iterative algorithm exhibits the increased PSNR better than Bicubic interpolation approach. 相似文献
24.
Hyoungho Ko 《International Journal of Electronics》2013,100(7):945-955
A highly configurable capacitive interface circuit with on‐chip calibration capability for tri‐axial microaccelerometer is presented. The capacitive interface circuit is designed to be programmable, and can reduce the output errors due to the parasitic capacitance variations and process variations. The capacitive sensing chain adopts the chopper stabilisation, and includes the front‐end charge amplifier with three 10‐bit programmable capacitor arrays, 9‐bit digital‐to‐analogue converter and 10‐bit programmable gain amplifier. The calibration coefficients are stored to the on‐chip erasable programmable read only memory. The outputs from the three‐channel capacitive sensing chain are converted to digital signal by the integrated 14‐bit algorithmic analogue‐to‐digital converter. After calibrating the 48 samples, all the samples meet the desired specification range. Before the calibration, the errors of the average values of the output offset and gain were +47.1% and ?85.9%, respectively. After the calibration, however, the errors of the average values of the output offset and gain are reduced to be 0.3% and 0.5%, respectively. The resolutions for x/y‐axis and z‐axis are measured to be 326 and 728?µg, respectively. 相似文献
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26.
A stochastic convergence analysis of the parameter vector estimation obtained by the recursive successive over-relaxation (RSOR) algorithm is performed in mean sense and mean-square sense. Also, excess of mean-square error and misadjustment analysis of the RSOR algorithm is presented. These results are verified by ensemble-averaged computer simulations. Furthermore, the performance of the RSOR algorithm is examined using a system identification example and compared with other widely used adaptive algorithms. Computer simulations show that the RSOR algorithm has better convergence rate than the widely used gradient-based algorithms and gives comparable results obtained by the recursive least-squares RLS algorithm. 相似文献
27.
In‐Hwan Ahn Seon Ju Yeo Kinam Jung Gumin Kang Dong‐Hun Shin Ho Seong Jang Byunghoon Kim Minwoo Nam Seok Joon Kwon Doo‐Hyun Ko 《Advanced functional materials》2020,30(13)
Upconversion nanoparticles (UCNPs) have been integrated with photonic platforms to overcome the intrinsically low quantum efficiency limit of upconversion luminescence (UCL). However, platforms based on thin films lack transferability and flexibility, which hinders their broader and more practical application. A plasmonic structure is developed that works as a multi‐functional platform for flexible, transparent, and washable near‐infrared (NIR)‐to‐visible UCL films with ultra‐strong UCL intensity. The platform consists of dielectric microbeads decorated with plasmonic metal nanoparticles on an insulator/metal substrate. Distinct improvements in NIR confinement, visible light extraction, and boosted plasmonic effects for upconversion are observed. With weak NIR excitation, the UCL intensity is higher by three orders of magnitude relative to the reference platform. When the microbeads are organized in a square lattice array, the functionality of the platform can be expanded to wearable and washable UCL films. The platform can be transferred to transparent, flexible, and foldable films and still emit strong UCL with a wide viewing angle. 相似文献
28.
29.
High step-up converter with coupled-inductor 总被引:4,自引:0,他引:4
Rong-Jong Wai Rou-Yong Duan 《Power Electronics, IEEE Transactions on》2005,20(5):1025-1035
In this study, a high step-up converter with a coupled-inductor is investigated. In the proposed strategy, a coupled inductor with a lower-voltage-rated switch is used for raising the voltage gain (whether the switch is turned on or turned off). Moreover, a passive regenerative snubber is utilized for absorbing the energy of stray inductance so that the switch duty cycle can be operated under a wide range, and the related voltage gain is higher than other coupled-inductor-based converters. In addition, all devices in this scheme also have voltage-clamped properties and their voltage stresses are relatively smaller than the output voltage. Thus, it can select low-voltage low-conduction-loss devices, and there are no reverse-recovery currents within the diodes in this circuit. Furthermore, the closed-loop control methodology is utilized in the proposed scheme to overcome the voltage drift problem of the power source under the load variations. As a result, the proposed converter topology can promote the voltage gain of a conventional boost converter with a single inductor, and deal with the problem of the leakage inductor and demagnetization of transformer for a coupled-inductor-based converter. Some experimental results via examples of a proton exchange membrane fuel cell (PEMFC) power source and a traditional battery are given to demonstrate the effectiveness of the proposed power conversion strategy. 相似文献
30.
Circularly polarized array antenna with corporate-feed network and series-feed elements 总被引:2,自引:0,他引:2
Ko Han Lu The-Nan Chang 《Antennas and Propagation, IEEE Transactions on》2005,53(10):3288-3292
In this paper, corporate-feed circularly polarized microstrip array antennas are studied. The antenna element is a series-feed slot-coupled structure. Series feeding causes sequential rotation effect at the element level. Antenna elements are then used to form the subarray by applying sequential rotation to their feeding. Arrays having 4, 16, and 64 elements were made. The maximum achieved gains are 15.3, 21, and 25.4 dBic, respectively. All arrays have less than 15 dB return loss and 3 dB axial ratio from 10 to 13 GHz. The patterns are all quite symmetrical. 相似文献