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71.
We have mass production on one kind of liquid crystal display (LCD) device with hybrid viewing‐angle (HVA), which can be switched between the wide viewing‐angle (WVA) and narrow viewing‐angle (NVA) by one button. This device adopts the single cell design that with lower cost, and utilizes the optical properties of electrically tilted LC to achieve the function of NVA display. An issue has received less attention in the past and been indeed found in the production process. It is that the off‐axis color shift will appear in NVA mode. We put forward one method to improve this issue here, which is combined with the concepts of Gray Frame Insertion (GFI) and Impulse‐type driving. By switching the voltage between two different γ values, the color shift will be perfected on the produce.  相似文献   
72.
Multi‐layer light field displays (MLLFDs) are a promising computational display type that can not only display hologram‐like 3D content but will also be well compatible with normal 2D applications. However, the quality of experience measurement for MLLFDs is always an important yet challenging issue. Despite existing research works on MLLFDs, most of them only provide quality of experience results with qualitative evaluation, for example, software simulation of a few 3D images/videos, rather than rigorous quantitative evaluation. This work targets at building a unified software and hardware measurement platform for different MLLFD methods, and comprehensively measuring both objective and subjective performance based on virtual object models. To the best of our knowledge, it is the first time that such performance has been measured for MLLFDs. In addition, to use the existing disclosed virtual object sequences, this paper further proposes three customized virtual models, which are the USAF‐E model, the view angle model, and the concave/convex object model for accurate measurement of spatial resolution, viewing angle, and depth resolution. A toolbox for MLLFD measurement with proposed models is also released in this paper. The experimental results demonstrate that our proposed measurement method, models, and toolbox can well measure MLLFDs in different configurations.  相似文献   
73.
现阶段大部分污水处理设备使用单一传感器监测设备,故障识别率低。该文研发了一套新型污水处理设备监测系统,根据信息物理融合系统(CPS)的要求全面统筹,采用BP神经网络算法处理由传感器得到的数据,监测设备的不同状态。硬件芯片采用STM32,采用工业以太网和串口通信,采用C#语言开发上位机应用软件,采用HTML和JavaScript以及C#语言开发web远程监测系统。经测试,系统运行良好,故障识别率高。  相似文献   
74.
视、听、说教学在大学英语教学中起着越来越重要的作用,如何提高大学生的英语听说能力已成为当前大学英语教学研究的一个热点。为此,对比了新模式下的视听说教学与传统英语听说教学,进而探讨了新模式下的视听说课程教学实践及其特点。实践表明:新模式有效地培养了学生的协作式互动学习与语言交际的能力。  相似文献   
75.
In the integral imaging (II) system using a curved micro‐lens array (MLA), the viewing angle is limited by the gap mismatch. Here, we propose a system to decrease the gap mismatch for enhancing the viewing angle. In the proposed system, a layer of high‐refractive‐index medium is assembled between the display panel and the curved MLA. The principle of the proposed II system is studied in detail. Simulations based on ray tracing are performed, and the results show that the proposed II system can effectively enhance the viewing angle.  相似文献   
76.
We propose an integral imaging (II) three‐dimensional (3D) display using a tilted barrier array and a stagger microlens array. The tilted barrier array consists of two orthogonally polarized sheets. In the stagger microlens array, the center of the microlens has p/2 shift with the elemental image along the horizontal direction, where p is the pitch of the microlens. The proposed II 3D display produces two different viewing zones and each of them is almost equal to that of the conventional II 3D display, and it has no crosstalk. We verify the feasibility of the proposed II 3D display in the simulation results.  相似文献   
77.
A viewing angle enhanced integral imaging display, which consists of a double microlens array, and a display panel is proposed. The double microlens array includes a convex microlens array and a concave microlens array. The display panel is used to display original elemental image array. The convex microlens array, located near the display panel, is used to provide a virtual elemental image array for the concave microlens array. The concave microlens array, located far away from the display panel, is used to display integral images with the virtual elemental image array. Compared with the original elemental image, the pitch for each virtual elemental image is magnified by the corresponding convex microlens. As a result, the viewing angle is expanded. Simulations based on ray‐tracing are performed and the results agree well with the theory.  相似文献   
78.
A comprehensive computer-graphics-based system (STERECON) is described for tracing and digitizing contours from individual or stereopair electron micrographs. The contours are drawn in parallel planes within the micrographs. Provision is also made for tracing and digitizing in full three-dimensional (3-D) coordinates in any direction along linear structures such as cytoskeletal elements. The stereopair micrographs are viewed in combination with the contours being traced on a graphics terminal monitor. This is done either by projecting original electron micrograph (EM) negatives onto a screen and optically combining these images with contour lines being drawn on the monitor, or by first digitizing the images and displaying them directly on the monitor along with the contour lines. Prior image digitization allows computer enhancement of the structures to be contoured. Correction and alignment routines are included to deal with variable section thickness, section distortion and mass loss, variations in photography in the electron microscope, and terminal screen curvature when combining projected images with contour lines on the monitor. The STERECON system organizes and displays the digitized data from successive sections as a 3-D reconstruction. Reconstructions can be viewed in any orientation as contour stacks with hidden lines removed; as wire-frame models; or as shaded, solid models with variable lighting, transparency, and reflectivity. Volumes and surface areas of the reconstructed objects can be determined. Particular attention was paid to making the system convenient for the biological user. Users are given a choice of three different stereo-viewing methods.  相似文献   
79.
Researchers have found that factors related to viewing content and viewing environment could influence viewers' stereoscopic viewing experiences. In this paper, the effect of both disparity and viewing ambient illumination condition on stereoscopic viewing was investigated by using an eye movement approach. The eye movement responses to random dot stereograms (RDS) stimuli in stereoscopic viewing were studied by performing a fusion range measurement experiment involving a judgment task. The fusion ranges under two ambient illumination conditions, eye movement responses to RDS stimuli and effects of disparity on eye movement parameters, were analyzed, respectively. The experimental results showed that fusion range under two ambient illumination conditions were different, and changes of eye movement parameters were different among various disparities when ambient illumination conditions varied. As a result, in order to improve viewers' viewing experiences when viewing different 3D contents, the arrangement of viewing ambient illumination conditions and the selection of disparity should be appropriately considered. The findings in this paper provide guidelines to reasonably arrange the viewing ambient illumination condition and efficiently produce healthy disparity in stereoscopic viewing.  相似文献   
80.
The large screens used in stadiums, shopping malls, and movie theaters typically have multiple viewers looking at them simultaneously. The quantification of these displays' image quality would require more considerations of measurements at different locations to satisfy the multiviewing condition. In this paper, we describe the practical implementation method involved in the current standardization activities. Additionally, a vantage point measurement method is studied. In the actual use case scenarios, the vantage point method is more appropriate. This method mimics the viewing behavior of audiences. The displays we measured were laser projection and LED. The method shows validity in both displays. Using the vantage point method, the experimental data show that the existing large displays may have very prominent differences in luminance and chromaticity at different viewing locations.  相似文献   
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