全文获取类型
收费全文 | 90篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 2篇 |
综合类 | 3篇 |
化学工业 | 1篇 |
金属工艺 | 1篇 |
机械仪表 | 2篇 |
建筑科学 | 33篇 |
能源动力 | 28篇 |
水利工程 | 2篇 |
无线电 | 7篇 |
一般工业技术 | 2篇 |
原子能技术 | 1篇 |
自动化技术 | 13篇 |
出版年
2023年 | 3篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2013年 | 11篇 |
2012年 | 2篇 |
2011年 | 8篇 |
2010年 | 8篇 |
2009年 | 8篇 |
2008年 | 7篇 |
2007年 | 8篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有95条查询结果,搜索用时 0 毫秒
1.
大规模三维地形与天空场景的实时渲染 总被引:1,自引:0,他引:1
诸峰 《计算机应用与软件》2009,26(5)
大规模三维室外场景包含大量的几何和纹理数据,给实时渲染带来了一定的难度.讨论基于四叉树结构的LOD地形和圆型天空体渲染方法,并在数据结构、可见性判定、算法实现等方面进行了优化,在此基础上,结合OpenGL和Visual Studio2005等工具进行开发和实验.实验结果表明,该方法能够根据不同的地形分辨率及视野范围,进行裁剪和剔除,有效地提高场景渲染的帧数,满足了实时渲染的要求. 相似文献
2.
Performance simulation applications require reliable information regarding the intensity of solar irradiance on arbitrarily oriented building surfaces in order to properly predict buildings' energy use or to configure building-integrated solar energy systems. Since measured irradiance databases typically include only horizontal irradiance values, solar radiation intensity on inclined surfaces must be computationally derived. In this context, the present paper compares six options to derive, from horizontal irradiance data, solar radiation intensity levels on inclined surfaces. To evaluate these options, simulated downward vertical irradiance on four orientations were compared with measurements obtained in Austria. Two options that use both global and diffuse horizontal irradiance values for sky radiance generation delivered slightly better results than the others, which require only global horizontal irradiance. However, the range of errors was rather high for all options. Even for the best-ranked option, no more than 64% of the results had a relative error of less than ±20%. 相似文献
3.
摘要:空中候梯厅是超高层建筑物电梯输送系统的重要组成部分,本文阐述了构成空中候梯厅的可调节转换台系统、横向移动的往复输送系统,以及穿梭电梯的系统结构、控制设计原理、运行操作技术,以及这些技术的应用,以期更合理地设计出高空电梯输送系统。 相似文献
4.
罗章波 《地下空间与工程学报》2011,7(1):185-193
青天寺隧道长度超过20 km,隧道的运营通风、防灾及救援(含紧急救援站)等,考虑的因素非常多,本文通过包兰铁路青天寺隧道运营通风及防灾救援设计的工程实例,介绍了特长隧道运营通风及防灾救援设计主要应考虑的问题和工程措施。通过数值模型计算,青天寺隧道运营通风得出可采用自然通风方式的结论;论述了定点救援和隧道内随机停车救援的原理和措施;对隧道内需要设置的通风机功率进行了详细的计算,对不同火灾工况的防灾通风形式、人员的疏散、风机的配置等进行了系统的论述。为以后类似工程设计提供参考。 相似文献
5.
The nature of scientific and technological data collection is evolving rapidly: data volumes and rates grow exponentially, with increasing complexity and information content, and there has been a transition from static data sets to data streams that must be analyzed in real time. Interesting or anomalous phenomena must be quickly characterized and followed up with additional measurements via optimal deployment of limited assets. Modern astronomy presents a variety of such phenomena in the form of transient events in digital synoptic sky surveys, including cosmic explosions (supernovae, gamma ray bursts), relativistic phenomena (black hole formation, jets), potentially hazardous asteroids, etc. We have been developing a set of machine learning tools to detect, classify and plan a response to transient events for astronomy applications, using the Catalina Real-time Transient Survey (CRTS) as a scientific and methodological testbed. The ability to respond rapidly to the potentially most interesting events is a key bottleneck that limits the scientific returns from the current and anticipated synoptic sky surveys. Similar challenge arises in other contexts, from environmental monitoring using sensor networks to autonomous spacecraft systems. Given the exponential growth of data rates, and the time-critical response, we need a fully automated and robust approach. We describe the results obtained to date, and the possible future developments. 相似文献
6.
The purpose of this work is to characterize the sky relative radiance and luminance distributions from the analysis of sky images acquired using a monochromatic CCD wide angle lens camera. The proposed methodology is based on the reduction of the number of the gray levels from the original image, in order to sharpen the different regions of the sky hemisphere, resulting in low level gray scale maps. In these maps each gray level is related to an intensity level and each pixel is associated to a sky direction. An experimental system that is able to simultaneously supply images from the sky and solar irradiance data was developed using a commercial CCD camera. The sky relative radiance and luminance distributions for different sky conditions were also determined. The resultant maps agree with observations of the main characteristics of sky radiance and luminance distributions. 相似文献
7.
8.
"别有洞天"是中国古典园林中营造"转"空间的特殊的造景主题之一。该文从宏观和微观两个方面论述了"别有洞天"的地宜条件的特殊利用,同时提出借"别有洞天"营造"转"空间的造景手法,如框景提示转折空间、加强空间对比等,也提出某些未以"别有洞天"为景名的景点也可以利用上述方法创造"别有洞天"的意境,如加强空间序列的收放对比、起伏对比、转折对比等,这些设计手法对现代风景园林中"转"空间的设计具有极好的启示作用。 相似文献
9.
Usama M. Fayyad Padhraic Smyth Nicholas Weir S. Djorgovski 《Journal of Intelligent Information Systems》1995,4(1):7-25
In areas as diverse as earth remote sensing, astronomy, and medical imaging, image acquisition technology has undergone tremendous improvements in recent years. The vast amounts of scientific data are potential treasure-troves for scientific investigation and analysis. Unfortunately, advances in our ability to deal with this volume of data in an effective manner have not paralleled the hardware gains. While special-purpose tools for particular applications exist, there is a dearth of useful general-purpose software tools and algorithms which can assist a scientist in exploring large scientific image databases. This paper presents our recent progress in developing interactive semi-automated image database exploration tools based on pattern recognition and machine learning technology. We first present a completed and successful application that illustrates the basic approach: the SKICAT system used for the reduction and analysis of a 3 terabyte astronomical data set. SKICAT integrates techniques from image processing, data classification, and database management. It represents a system in which machine learning played a powerful and enabling role, and solved a difficult, scientifically significant problem. We then proceed to discuss the general problem of automated image database exploration, the particular aspects of image databases which distinguish them from other databases, and how this impacts the application of off-the-shelf learning algorithms to problems of this nature. A second large image database is used to ground this discussion: Magellan's images of the surface of the planet Venus. The paper concludes with a discussion of current and future challenges. 相似文献
10.
Mauritius is considered to have high solar resource potential but it has not yet been fully quantified and exploited due to the lack of valid solar energy data. This paper unveils the solar potential of Mauritius. Ground-based measurements were performed at intervals of 30 s in order to obtain accurate global horizontal irradiance data which can depict all changes in solar power. The latter is used to evaluate average monthly global horizontal irradiance, maximum irradiance, monthly average insolation and monthly sky clearness index. A solar geometry model was used to define the average monthly, seasonal and yearly maximum elevations and extraterrestrial radiation. Measurement data were compared to Meteonorm and NASA SSE 3-hourly averaged solar data. Comparison shows that average irradiance values are in good agreement, whereas insolation and sky clearness values obtained from external sources are inferior to high quality measurement data. The results, presented in this paper, complement solar data of Meteonorm and NASA SSE and secondly, provides PV and solar engineers as well as scientists with highly valuable information on the solar resource of Mauritius that can be used during planning and design of PV systems as well as for conducting further research in Mauritius and surrounding regions. 相似文献