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991.
Huang-Chung Cheng Fang-Shing Wang Chun-Yao Huang 《Electron Devices, IEEE Transactions on》1997,44(1):64-68
The NH3-plasma passivation has been performed on polycrystalline silicon (poly-Si) thin-film transistors (TFT's), It is found that the TFT's after the NH3-plasma passivation achieve better device performance, including the off-current below 0.1 pA/μm and the on/off current ratio higher than 108, and also better hot-carrier reliability than the H2-plasma devices. Based on optical emission spectroscopy (OES) and secondary ion mass spectroscopy (SIMS) analysis, these improvements were attributed to not only the hydrogen passivation of the defect states, but also the nitrogen pile-up at SiO2/poly-Si interface and the strong Si-N bond formation to terminate the dangling bonds at the grain boundaries of the polysilicon films. Furthermore, the gate-oxide leakage current significantly decreases and the oxide breakdown voltage slightly increases after applying NH3-plasma treatment. This novel process is of potential use for the fabrication of TFT/LCD's and TFT/SRAM's 相似文献
992.
Yuhua Cheng Min-Chie Jeng Zhihong Liu Jianhui Huang Mansun Chan Kai Chen Ping Keung Ko Chenming Hu 《Electron Devices, IEEE Transactions on》1997,44(2):277-287
A new physical and continuous BSIM (Berkeley Short-Channel IGFET Model) I-V model in BSIM3v3 is presented for circuit simulation. Including the major physical effects in state-of-the art MOS devices, the model describes current characteristics from subthreshold to strong inversion as well as from the linear to the saturation operating regions with a single I-V expression, and guarantees the continuities of Ids, conductances and their derivatives throughout all Vgs, Vds, and Tbs, bias conditions. Compared with the previous BSIM models, the improved model continuity enhances the convergence property of the circuit simulators. Furthermore, the model accuracy has also been enhanced by including the dependencies of geometry and bias of parasitic series resistances, narrow width, bulk charge, and DIBL effects. The new model has the extensive built-in dependencies of important dimensional and processing parameters (e.g., channel length, width, gate oxide thickness, junction depth, substrate doping concentration, etc.). It allows users to accurately describe the MOSFET characteristics over a wide range of channel lengths and widths for various technologies, and is attractive for statistical modeling. The model has been implemented in the circuit simulators such as Spectre, Hspice, SmartSpice, Spice3e2, and so on 相似文献
993.
Er-doped glass ridge-waveguide amplifiers fabricated with a collimated sputter deposition technique 总被引:1,自引:0,他引:1
Cheng Chung Li Hong Koo Kim M. Migliuolo 《Photonics Technology Letters, IEEE》1997,9(9):1223-1225
We report a new fabrication process for Er-doped glass ridge waveguides. The process does not require etching of an Er-doped film in defining the lateral dimension of a waveguide, but involves a liftoff process using polyimide as a sacrificial layer. An Er-doped soda-lime silicate glass film (1.5 /spl mu/m thick) was deposited at 350/spl deg/C using a collimated sputtering technique. Conventional sputtering techniques have been known to be incompatible with a liftoff process. The collimated sputtering, however, allowed us easy liftoff of Er-doped films, and produced well-defined ridges with smooth surface profiles. A 1.7-cm-long waveguide thus fabricated shows a 1.55-/spl mu/m signal enhancement of 15.4 dB with a 980-nm pump power of 40 mW. This enhancement fully compensates for both Er absorption and waveguide losses, and results in a gain of 7.2 dB. 相似文献
994.
995.
CCD图像传感器的市场与发展 总被引:10,自引:0,他引:10
随着微电子技术的发展,CCD图像传感器的产量不断增加,应用领域不断扩展。本文对CCD图像传感器的市场情况进行了分析与预测。对影响CCD传感器市场未来发展具有重要作用的数字照像机的市场情况作了专门的介绍,并在充分描述了CCD图像传感器市场情况的基础上,对目前国内外CCD图像传感器的发展趋势作了初步探索。 相似文献
996.
野外复杂背景下红外图像的目标检测 总被引:7,自引:3,他引:7
野外复杂背景下红外图像序列目标检测是红外野外监视中的重点问题。大量的背景物增加了目标检测的难度。文中针对野外复杂背景下红外图像序列的特点,提出了一种实用的运动目标检测算法。该算法包括两个处理步骤:首先,在场景配准后利用帧间差图像提取目标的运动信息,并据此进行目标的粗检测;其次,合目标运动在时间和空间上的相关性进行精检测。粗检测的低漏判度和精检测的低误差率保证了算法的可靠性。在检测的同时算法确定了目 相似文献
997.
介绍了中波和长波“红外小光点扫描测试系统”。该系统由红外聚焦光学子系统,六维精密扫描工件台及数据采集子系统构成。可用于红外焦平面器件重要性能参数如串音、响应均匀性、转移效率的测量,也可用于单元红外探测器有效响应面积和响应均匀性等参数的测量。 相似文献
998.
999.
Cheng Jiao Cangellaris A.C. Yaghmour A.M. Prince J.L. 《Advanced Packaging, IEEE Transactions on》2000,23(2):132-141
Sensitivity analysis of multiconductor transmission lines is derived from a new, all-purpose multi-conductor transmission line model in both frequency domain and time domain. Computer implementation of this new model as well as the sensitivity analysis has been completed. It enables efficient, accurate simulations of interconnect circuit responses as well as sensitivity analysis with respect to both electrical and physical transmission line parameters. By applying sensitivity analysis to high-speed interconnect circuit design, design variables are optimized to achieve simultaneous minimization of crosstalk, delays and reflections at desired nodes in the circuit without violating any indispensable design rules. Numerical examples are presented to demonstrate the validity of the proposed sensitivity analysis and illustrate its application to the optimization of high-speed interconnect circuit design 相似文献
1000.
He Jianhua Subramanian K.R. Yang ZongKai Cheng Wenqing 《Communications Letters, IEEE》2000,4(12):423-425
In this letter, we propose a tandem broadcast selective repeat (SR) ARQ scheme for satellite communications. In the scheme, the satellite operates in a store and forward manner, which minimizes the effect of the large round-trip delay. Numerical results show that the proposed scheme would largely improve the system performance 相似文献