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601.
Japan is leading the world with the adoption of new mobile data services such as Internet services and with a resulting boost in data ARPU (average revenue per user). In the development of these services, many functions have been integrated into mobile handsets, which has resulted in a convergence of, so far, separate consumer electronic devices. This article addresses the following questions: What are the drivers of this process? What could European players, in particular the European policymakers do to catch up? According to our research, a major driver of the process in Japan is tough competition among operators, which in turn is driven by factors such as competition in mobile radio infrastructure. The author arrives at the following conclusions for European policies: (1) There should be more awareness of the Japanese lead, e.g., of the crucial role of Internet push e-mail. (2) Europe could benefit from more operators willing to bear the risk of introducing new technologies. (3) For a successful introduction of infrastructure competition, it could make sense to make spectrum bands available with European-wide licenses.  相似文献   
602.
为满足大视场、多个图像传感器同时使用、多光电图像传感器成像系统的响应一致性等技术需求,设计了一种大视场的成像系统.将先进先出缓存(FIFO)应用到数据传输技术当中,保证了系统多种图像数据同步实时输出;在基于低压差分信号(LVDS)技术上同时采用Camera link接口协议,设计了一种低成本、高速、稳定、简易的双目半导体金属氧化物有源传感器(CMOSAPS)成像系统,并深入探讨了系统的基本组成和工作原理;利用可编程门阵列完成自上而下的模块设计;并对系统部分工作时序进行了仿真,并进行板上调试;结果表明,本设计方案满足系统的大视场需求,为后续的图像采集工作打下了坚实的基础.  相似文献   
603.
本文首先阐述了基于FPGA和ARM的雷达视频混合显示技术的必要性,介绍了该显示技术的工作原理,以及视频处理通道的工作原理,对Camera接口、ITU-R BT601/656视频编码、显示控制器视频混合叠加、高分辨显示数据的实时混合等工作原理分别进行了阐述,详细分析了雷达视频混合显示是如何利用上述原理来实现。通过工程试验,验证了该显示技术的有效性。  相似文献   
604.
针对成像器稳定装置中由于摩擦力距造成的跟踪误差这一问题,采用自适应滑模控制的方法对摩擦力矩进行有效补偿,并且提出了基于改进欧拉近似法从位置测量信号中获取速度信号的方法。通过在成像器稳定装置控制系统中的实际应用,表明提出的方法有效地减小了成像器稳定装置的跟踪误差,算法简单、易于实现。  相似文献   
605.
Allen Funt, creator of Candid Camera, spontaneous recordings of human behavior presented via radio, film and television, invited Evans to organize and chair a 4 day conference "to explore the potential of the already available film and the Candid Camera technique in general for research purposes; to speculate on theoretical formulations in social science which allow this candid behavior to be placed in perspective; to explore their utilization for formal and informal educational purposes; simply to share the materials with educators and researchers who had indicated an interest in them." Participants included psychologists, sociologists, educators, clergymen, publishers, government agency representatives, etc. Conference activities are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
606.
A method for measuring parcel area based on the instantaneous field of view of the UAV is proposed. Firstly, the internal and external parameters and distortion parameters of the camera on UAV are obtained by calibration, and the single image of the land parcel is corrected for distortion. Then extract the target parcel area in the image and count the number of pixels in the area. The actual area of the plot is obtained by estimating the ratio of pixels to area.The experimental results show that the calculation accuracy of this method increases with the increase of the flying height of the UAV. The calculation accuracy gradually increases after reaching a peak, and the relative error within the effective flight altitude is below 10% ,which can effectively calculate the parcel area. This method has practical significance for mountain operations requiring simple and fast operation and relatively low precision.  相似文献   
607.
Fusion of information gathered from multiple sources is essential to build a comprehensive situation picture for autonomous ground vehicles. In this paper, an approach which performs scene parsing and data fusion for a 3D-LIDAR scanner (Velodyne HDL-64E) and a video camera is described. First of all, a geometry segmentation algorithm is proposed for detection of obstacles and ground areas from data collected by the Velodyne scanner. Then, corresponding image collected by the video camera is classified patch by patch into more detailed categories. After that, parsing result of each frame is obtained by fusing result of Velodyne data and that of image using the fuzzy logic inference framework. Finally, parsing results of consecutive frames are smoothed by the Markov random field based temporal fusion method. The proposed approach has been evaluated with datasets collected by our autonomous ground vehicle testbed in both rural and urban areas. The fused results are more reliable than that acquired via analysis of only images or Velodyne data.  相似文献   
608.
在一个视频监控系统进入调试阶段、试运行阶段以及交付使用后,都有可能出现这样那样的故障现象,这些故障现象或是不能正常运行,或是系统达不到设计要求的技术指标;或是整体性能和质量不理想。这些问题对于一个安防工程项目来说,是在所难免的。出现问题后,去设法解决它们,则是工程技术人员应尽的义务和责任。  相似文献   
609.
用莫尔等高技术对非规则照相机外形曲面的测试进行了原理上的阐述。运用计算机对测试实验的参数进行了分析,并给出了实验莫尔条纹图形。  相似文献   
610.
Camera-oriented quality assessment (CQA) differs from traditional image quality assessment (IQA) in that “distorted” images are straight out of real devices instead of various types and levels of artificial operations. However, despite its value for both customers and manufacturers, academic and industrial fields, there are few CQA databases created years ago. To reflect recent mobile imaging advancements, we present a new massive Phone Camera Benchmarking database (PCB2021) in this paper. In PCB2021, 40 modern phone units featuring photography are simultaneously compared in 182 scenes for a total of 7280 images, which can be classified into six categories (sub-datasets) based on different focal lengths and user cases: main camera (107), ultra-wide (20), 2×, 3×, 5× zoom lenses (26, 8, 10) and night-mode (11). The shooting process begins from 7:00 am to 11:00 pm and lasts more than a month. In the subjective study, to overcome the high-resolution-induced overall quality evaluation difficulty, five image attributes: exposure/contrast, color, sharpness, graininess, artifacts are assessed separately on each dataset. To reduce ranking complexity for large-scale cameras, a dynamic anchor ruler method is proposed to obtain quality orders efficiently. With the constructed PCB2021, we further evaluate 15 mainstream no-reference (NR) IQA algorithms. The finding is that for zoomed images, sharpness metrics can achieve Spearman correlation coefficients above 0.8, while for the subtle main camera and night-mode images, performances of all fifteen algorithms drop down quickly, i.e. 0.1-0.2 for the former and 0.5 for the latter. The entire database, expert rankings and algorithm performance reports will be freely available on request.  相似文献   
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