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61.
本文分析了我国现阶段农村金融市场的现状及其在农村市场中发展滞后的原因,阐述了我国城乡"二元经济"结构决定了要建设一个不同于城乡金融"一盘棋"的城乡"二元金融"结构,以促进社会主义新农村的建设。 相似文献
62.
艾丽 《江汉石油职工大学学报》2013,26(2):60-61,64
开展党员双重管理是油田加强社区党建的新尝试、新举措。进一步推动党员双重管理,一是要完善教育引导机制,增强党员参与的自觉性和主动性;二是要完善协调联动机制,增强党员参与工作的推动力和执行力;三是要完善组织运行机制,增强党员双重管理工作的规范性和有效性;四是要完善考核激励机制,增强党员双重管理工作的严肃性和持续性。 相似文献
63.
64.
为解决具有以太网接口的小型功率设备供电不便的问题,在分别分析IEEE 802.3af标准中的以太网供电系统构成、以太网供电传输方式、以太网供电过程及其他电气特性的基础上,提出了一种通过以太网获取电源的解决方案,并给出了详细的电路设计原理图。该方案可同时支持以太网供电输入和其他辅助电源输入,并可以同时输出3.3 V和5 V这2种电压供系统使用。测试结果表明,该设计方案具有较低的成本和较高的效率,能够很好地解决小型功率设备供电不便的问题。 相似文献
65.
We describe an active-set, dual-feasible Schur-complement method for quadratic programming (QP) with positive definite Hessians. The formulation of the QP being solved
is general and flexible, and is appropriate for many different application areas. Moreover, the specialized structure of the
QP is abstracted away behind a fixed KKT matrix called Ko and other problem matrices, which naturally leads to an object-oriented software implementation. Updates to the working set
of active inequality constraints are facilitated using a dense Schur complement, which we expect to remain small. Here, the
dual Schur complement method requires the projected Hessian to be positive definite for every working set considered by the
algorithm. Therefore, this method is not appropriate for all QPs. While the Schur complement approach to linear algebra is
very flexible with respect to allowing exploitation of problem structure, it is not as numerically stable as approaches using
a QR factorization. However, we show that the use of fixed-precision iterative refinement helps to dramatically improve the
numerical stability of this Schur complement algorithm. The use of the object-oriented QP solver implementation is demonstrated
on two different application areas with specializations in each area; large-scale model predictive control (MPC) and reduced-space
successive quadratic programming (with several different representations for the reduced Hessian). These results demonstrate
that the QP solver can exploit application-specific structure in a computationally efficient and fairly robust manner as compared
to other QP solver implementations. 相似文献
66.
Lanthanum oxide films were fabricated using dual plasma deposition. X-ray photoelectron spectroscopy (XPS) showed that La existed in the + 3 oxidation state. X-ray diffraction (XRD) revealed a (101) oriented hexagonal structure. Blood platelet adhesion tests and endothelial cell cultures were used to evaluate the hemocompatibility of the as-deposited films. Scanning electron microscopy (SEM) and optical microscopy were employed to evaluate the surface morphology of the blood platelets and endothelial cells on the films. The results showed that the number of adhered, aggregated and morphologically changed platelets was reduced compared to that observed on low-temperature isotropic carbon (LTIC). Endothelial cells culture tests indicated good adhesion and proliferation of human umbilical vein endothelial (HUVE) cells in vitro. Our study suggests that lanthanum oxide films are potential blood-contacting biomedical materials. 相似文献
67.
The fabrication of silicon based micromechanical sensors often requires bulk silicon etching after aluminum metallization. All wet silicon etchants including ordinary undoped tetramethyl ammonium hydroxide (TMAH)-water solution attack the overlaying aluminum metal interconnect during the anisotropic etching of (100) silicon. This paper presents a TMAH-water based etching recipe to achieve high silicon etch rate, a smooth etched surface and almost total protection of the exposed aluminum metallization. The etch rate measurements of (100) silicon, silicon dioxide and aluminum along with the morphology studies of etched surfaces are performed on both n-type and p-type silicon wafers at different concentrations (2, 5, 10 and 15%) for undoped TMAH treated at various temperatures as well as for TMAH solution doped separately and simultaneously with silicic acid and ammonium peroxodisulphate (AP). It is established through a detailed study that 5% TMAH-water solution dual doped with 38 gm/l silicic acid and 7 gm/l AP yields a reasonably high (100) silicon etch rate of 70 μm/h at 80 °C, very small etch rates of SiO2 and pure aluminum (around 80 Å/h and 50 Å/h, respectively), and a smooth surface (±7 nm) at a bath temperature of 80 °C. The etchant has been successfully used for fabricating several MEMS structures like piezoresistive accelerometer, vaporizing liquid micro-thruster and flow sensor. In all cases, the bulk micromachining is carried out after the formation of aluminum interconnects which is found to remain unaffected during the prolonged etching process at 80 °C. The TMAH based etchant may be attractive in industry due to its compatibility with standard CMOS process. 相似文献
68.
研究了一种高功率因数的双开关升压整流器的单周期控制方法。在该整流器中。二极管整流电路和功率因数校正环节结合在一起。减少了导通损耗。具有效率高,结构简单等特点。但是由于升压电感在交流侧,电流和电压检测不是很方便。为此,引进单周期控制技术。它不需要检测交流输入电压。而且对输入电流的检测也相对简单。同时单周期控制电路具有简单可靠、响应快、成本低、易于实现等特点。文中较为详细地分析了单周期控制双开关升压整流器的工作原理和实现方式,最后在PSpice中进行了仿真验证。 相似文献
69.
提出了一种多回路平面曲线的分割算法。算法以直线段和二次曲线段作为拟合的基本单元,通过边缘跟踪把多回路的平面曲线分割成曲线段或单回路的封闭曲线,然后在曲线曲率不连续处继续分割。针对一次分割时可能会产生的迷向问题,提出了基于对偶原理的线段合并技术。该算法的结果能简单有效地描述场景中的物体,使高级视觉任务更简单。实验结果表明算法能取得较好的效果。 相似文献
70.
煤气贮罐贮气量的检测是一个困扰煤气行业的技术难题。目前用机械式码盘指示贮气量的测量装置仍应用广泛,操作人员用目测法读取指针示值,常会出现漏报和误报数据的情况,将两只电位器式传感器用变速结构连接起来,构成了一种具有细分功能的电位器式传感器。通过建立电位器传感器的数学模型和编制单片机的应用软件,能精确计算煤气的体积。本装置成功地用于干式煤气贮罐贮气量的自动检测系统中,现场运行几年来,工作稳定、性能可靠。 相似文献