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11.
采用常压化学气相沉积(APCVD)技术在铝基底上成功制备了改性SiOx陶瓷薄膜。通过显微硬度测试与涂层附着力自动划痕测试定量研究了薄膜显微硬度和膜基结合强度,利用光学显微镜(0M)和扫描电子显微镜(SEM)观察了薄膜的原始表面以及压痕、划痕形貌。结果表明,SiOx膜层由大小不均匀的等轴状颗粒团聚堆垛而成,退火处理时长大或融合成片状;SiOx薄膜有效提高纯铝表面的硬度,并能通过SiOx薄膜变形以松弛表层应力,抑制脆性裂纹产生;划痕测试证明基底和薄膜具有很高的结合强度,薄膜与基底发生塑性变形而不剥离。 相似文献
12.
Chengqiang Huang Qi Zhang Hui Wang Songlin Feng 《Journal of the Society for Information Display》2016,24(12):713-720
A selective current limit algorithm based on color space conversion is proposed in this paper. There are mainly two advantages for this algorithm. Firstly, only the luminance component Y is decreased, and the color component Cb or Cr is not changed; thus, the color distortion is avoided in the process of current limit. Secondly, the current of pixels with high luminance is limited while that of those pixels with low luminance is not, which means current limit is executed selectively. For the same value of mean square error, the simulation results show that the ratio of pixels with high luminance of the image processed by the proposed algorithm is zero, and that processed by the net power control and the algorithm based on color space conversion is 0.081 and 0.0854, respectively. This algorithm is implemented on a field‐programmable gate array to drive the image display on the AMOLED panel. 相似文献
13.
Songlin Hu 《Asian journal of control》2013,15(5):1538-1542
This paper is devoted to the consensus protocol design for a set of agents with fractional‐order uncertainty dynamics where the fractional order α satisfies 0 < α < 2. For multi‐agent systems (MASs) with fixed undirected topology, a distributed static output feedback protocol is proposed with an undetermined system matrix. Based on model transformation and fractional‐order stability theory, sufficient conditions are derived to ensure the consensus of MASs in terms of linear matrix inequalities (LMIs). Finally, a simulation example is employed to validate the effectiveness of the proposed consensus protocol. 相似文献
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为了能够在复杂环境下实现风速风向的高精度和高稳定性测量,在基于声学共振原理的风传感器系统的基础上,采用闭环控制扫描技术改进了系统的性能指标。采用声学共振的方式,同时对换能器产生的信号进行频率调制和强度调制,实现对超声换能器的线型扫描。频率调制解决了在不同压力、温度等环境因素影响下导致的共振频移的问题,强度调制解决了换能器性能随时间衰减问题,极大地提高了信噪比。实验结果表明,采用闭环控制的方法可以准确测量风速风向。风速测量范围0~50 m/s,风速测量精度为±0.5 m/s(≤15m/s)/±5%(>15 m/s且<35 m/s)/±9%(>35 m/s)。改进后的系统在复杂环境下受环境变化影响小、精度高、稳定性好、抗干扰能力强。 相似文献
16.
Xianhong Zheng Songlin Zhang Mengjuan Zhou Haibo Lu Shuai Guo Yaoxin Zhang Changlong Li Swee Ching Tan 《Advanced functional materials》2023,33(19):2214880
Breathable, flexible, and highly sensitive pressure sensors have drawn increasing attention due to their potential in wearable electronics for body-motion monitoring, human-machine interfaces, etc. However, current pressure sensors are usually assembled with polymer substrates or encapsulation layers, thus causing discomfort during wearing (i.e., low air/vapor permeability, mechanical mismatch) and restricting their applications. A breathable and flexible pressure sensor is reported with nonwoven fabrics as both the electrode (printed with MXene interdigitated electrode) and sensing (coated with MXene/silver nanowires) layers via a scalable screen-printing approach. Benefiting from the multi-layered porous structure, the sensor demonstrates good air permeability with high sensitivity (770.86–1434.89 kPa−1), a wide sensing range (0–100 kPa), fast response/recovery time (70/81 ms), and low detection limit (≈1 Pa). Particularly, this sensor can detect full-scale human motion (i.e., small-scale pulse beating and large-scale walking/running) with high sensitivity, excellent cycling stability, and puncture resistance. Additionally, the sensing layer of the pressure sensor also displays superior sensitivity to humidity changes, which is verified by successfully monitoring human breathing and spoken words while wearing a sensor-embedded mask. Given the outstanding features, this breathable sensor shows promise in the wearable electronic field for body health monitoring, sports activity detection, and disease diagnosis. 相似文献
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我国仪器仪表与测量控制科技的发展 总被引:1,自引:0,他引:1
从战略高度,深刻全面地论述了仪器仪表与测量控制在当今社会的重要地位和作用、我国仪器仪表与测量控制的基本概况以及今后发展的趋势和特点,特别指出我国工业自动化仪表与控制系统以及科学仪器未来发展的关注点.同时,阐述了我国仪器仪表与测量控制近年来的重大进展,指明了我国仪器仪表与测量控制自主创新发展的方向. 相似文献
19.
In this paper, we present an interval model of networked control systems with time-varying sampling periods and time-varying network-induced delays and discuss the problem of stability of networked control systems using Lyapunov stability theory. A sufficient stability condition is obtained by solving a set of linear matrix inequalities. In the end, the illustrative example demonstrates the correctness and effectiveness of the proposed approach. 相似文献
20.
H Gerlach R Rossaint WO Bechstein G Blumhardt P Neuhaus K Falke 《Canadian Metallurgical Quarterly》1993,19(3):282-285
Complications in patients undergoing OLT, such as hemorrhagic events, are caused not only by surgical problems but also by the profound functional disturbances arising from hepatic insufficiency, which are at least partially cured by the procedure itself. Preoperative clotting data give insight only into the dysfunction of the explanted organ. Hence, we tried to perform a standardized, "goal-directed" anesthesiologic management in the perioperative phase in OLT, following strict indications for blood replacement according to diuresis, hemoglobin level, and hemodynamic parameters. We performed 200 OLTs in 185 patients, according to usual methods. The mean intraoperative fluid requirement was 884 ml of balanced salt solution, 8.1 units of RBC, and 9.4 units of FFP. During the first 24 hours postoperatively, an average of 2.4 units of RBC and 5.6 units of FFP had to be transfused. Currently, 170 of the 185 patients (91.9%) are alive and well. Our data demonstrate that a distinct reduction of transfusion rates in OLT is possible, neglecting clotting data and improving clotting function by avoiding hemodilution. 相似文献