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61.
62.
It is a truth, universally ignored, that a single metric of color rendering must be in want of another. Evidence presented here, together with those from an earlier study, strongly suggest that the quest for a single metric to quantify color rendering will be in vain. Rather, the strengths of color rendering index (CRI) and of gamut area index (GAI) † seem to counteract the weaknesses of one another, such that together they can be used to guide lighting practitioners in choosing a source that will provide good color rendering of most objects in most applications. The present study was conducted to determine whether sources, both warm and cool, with high levels of both CRI (above 80) and GAI (above 80 and less than 100) were judged better than ones with high levels of just CRI or just GAI. The results support the conclusion that a two‐metric system of color rendering is needed for general illumination applications. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010 相似文献
63.
为解决飞行仿真领域其视景系统对逼真、复杂场景渲染质量要求高的问题,提出基于延迟着色技术的大场景反走样渲染架构以实现全球地景及场景特效的真实感渲染,达到飞行训练的效果。本渲染架构主要解决延迟着色技术与硬件反走样技术——覆盖采样反走样(CSAA)不兼容的问题,在延迟阶段生成带CSAA反走样的多渲染目标缓存(G-Buffer),在着色阶段通过记录在特定通道中的透明度蒙版信息进行几何体边缘恢复以进行最终的光照计算;对不同绘制组件开启不同等级的反走样等级以达到效果与效率的平衡,并利用类层次细节(LOD)模型构建技术及标记重要边界信息进行后处理等加强反走样效果。采用本渲染架构开发的视景系统,从实际训练及实验所得到的数据与效果表现上决定不同负载组件最终的采样倍数,这样系统的实时性高(>60 fps),能达到飞行模拟视景对渲染效率的要求,减少延迟与卡顿;同时该框架反走样效果好于亚像素还原反走样(SRAA)算法,从而视景系统能达到性能与画质的最佳组合。通过实际训练与飞行模拟专家鉴定,基于该框架系统的视景系统能达到飞行仿真训练的目的。 相似文献
64.
This study investigates colour harmony in visual experiments in order to develop a new quantitative colour harmony model. On the basis of new experimental results, colour harmony formulae were developed to predict colour harmony from the CIECAM02 hue, chroma, and lightness correlates of the members of two‐ or three‐colour combinations. In the experiments, observers were presented two‐ and three‐colour combinations displayed on a well‐characterized CRT monitor in a dark room. Colour harmony was estimated visually on an 11 category scale from ?5 (meaning completely disharmonious) to +5 (meaning completely harmonious), including 0 as the neutral colour harmony impression. From these results, mathematical models of colour harmony were developed. The visual results were also compared with classical colour harmony theories. Two supplementary experiments were also carried out: one of them tested the main principles of colour harmony with real Munsell colour chips, and another one compared the visual rating of the new models with existing colour harmony theories. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010. 相似文献
65.
66.
视频监控是大型安防工作中最重要的一个环节,传统的视频监控系统展示给用户的只是独立的二维平面图像,图像脱离环境,整体性不足,为了解决该问题,提出了将视频图像渲染显示于三维模型的思路.研究了纹理映射技术并结合视频图像渲染的特殊性分析研究了Z缓冲算法、Shadow map算法,根据实际应用提出Extend Shadow map算法以实现将视频图像与三维场景无缝贴合.实验结果表明,视频图像渲染显示于三维模型中所体现的优越性. 相似文献
67.
Olivier Terraz Guillaume Guimberteau Stéphane Mérillou Dimitri Plemenos Djamchid Ghazanfarpour 《The Visual computer》2009,25(2):165-180
In this paper an extension of L-systems is proposed, based on three-dimensional (3D) generalized maps that allow an easier control of the internal structure of 3D objects. A first and original application of this extension is also proposed: wood modelling by growth simulation. Numerous other applications of our work are possible, in the area of computer graphics, as well as in botanical science. 相似文献
68.
研究三维动画渲染领域的渲染集群能耗问题,采用基于神经网络的任务量预测模型,结合渲染系统任务量历史数据统计,提出基于多步预测的渲染集群自动开-关机控制算法和节能控制架构,并通过实际数据验证了节能控制方法的有效性。 相似文献
69.
李亚峰 《计算机工程与应用》2009,45(14):176-178
由于日光模型的复杂性,逼真地绘制日光照射下户外场景的真实感图像是一个困难的问题。目前的绘制方法或者因为采用的模型过于简单而真实感程度差,或者绘制过程过于复杂耗时而影响其应用。应用图像相似度理论,提出了一种综合使用基于几何和基于图像的混合绘制方法。绘制过程分为两步,首先,使用简单的光照模型近似绘制场景,然后,采用基于图像的绘制和处理方法补充第一步无法表现的效果。由于采用了基于图像相似度理论的方法,能够克服基于图像绘制技术需要处理巨大数据量的缺点。用这种两步法绘制自然光照下的户外景物,只需要简单的光照模型和物体材质属性以及很少的数据存储量。该方法在真实感程度、绘制速度和数据存储量三者间取得了比较好的平衡,绘制建筑物的实验证明了方法的有效性。 相似文献
70.
Cristian Bernareggi Piero Mussio Loredana Parasiliti Provenza 《Journal of Visual Languages and Computing》2009,20(5):326-340
Notation is a tool of thought, recording and communicating concepts and activities related to a domain of knowledge. In the history of mathematical notation, written notation is usually considered. However, to be an effective thinking tool, notation must be properly perceived. Blind and partially sighted people run into difficulty in making, exploring and understanding mathematical concepts conceived for being represented in multi-dimensional space. In this paper, we capitalize on the multifaceted nature of digital symbols to define multimodal digital notation for graph structures that allows blind and partially sighted people to represent graph structures, reason about them and communicate their reasoning with sighted people as well as each other. As support tool for notation proposed we have designed a multimodal interactive system, in which haptic signals play a crucial role. An evolutionary prototype of the system has been developed and evaluated according to the star life cycle model. 相似文献