全文获取类型
收费全文 | 183篇 |
免费 | 15篇 |
国内免费 | 4篇 |
学科分类
工业技术 | 202篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2016年 | 12篇 |
2015年 | 8篇 |
2014年 | 7篇 |
2013年 | 11篇 |
2012年 | 12篇 |
2011年 | 5篇 |
2010年 | 8篇 |
2009年 | 12篇 |
2008年 | 4篇 |
2007年 | 8篇 |
2006年 | 13篇 |
2005年 | 7篇 |
2004年 | 12篇 |
2003年 | 11篇 |
2002年 | 6篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 7篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1977年 | 2篇 |
排序方式: 共有202条查询结果,搜索用时 390 毫秒
1.
曲线的透视不变性分割在基于二次曲线的三维重建中非常重要。首先给出了连续曲线零曲率点和角点的提取法,在数字图像中曲经是不连续的,曲率的变化受噪声的干扰很大。在这种情况下为了检测出零曲率点和角点,对曲线采用了高斯滤波然后再提到零曲率点和角点。实验证明这种方法效果优于直接求曲率法。 相似文献
2.
针对观点句的特点提出了适合观点句识别的特征抽取规则.在此基础上,融合图论中最小割原理和机器学习分类方法,引入知识图的概念,并提出了基于知识图的观点句识别算法.以公开评测语料、自建语料和开放语料进行了相关实验,结果表明:基于知识图的观点句识别算法的分类性能和稳定性有明显优势. 相似文献
3.
Experiencing Nature: Embodying Animals in Immersive Virtual Environments Increases Inclusion of Nature in Self and Involvement With Nature 下载免费PDF全文
Sun Joo Ahn Joshua Bostick Elise Ogle Kristine L. Nowak Kara T. McGillicuddy Jeremy N. Bailenson 《Journal of Computer-Mediated Communication》2016,21(6):399-419
Immersive virtual environments (IVEs) produce simulations that mimic unmediated sensory experiences. 3 experiments (N = 228) tested how different modalities increase environmental involvement by allowing users to inhabit the body of animals in IVEs or watch the experience on video. Embodying sensory‐rich experiences of animals in IVEs led to greater feeling of embodiment, perception of being present in the virtual world, and interconnection between the self and nature compared to video. Heightened interconnection with nature elicited greater perceptions of imminence of the environmental risk and involvement with nature, which persisted for 1 week. Although the effect sizes were small to moderate, findings suggest that embodied experiences in IVEs may be an effective tool to promote involvement with environmental issues. 相似文献
4.
《Advanced Engineering Informatics》2015,29(4):958-970
The purpose of this research is to suggest and develop a building information modeling (BIM) database based on BIM perspective definition metadata for connecting external facility management (FM) and BIM data, which considers variability and expandability from the user’s perspective. The BIM-based FM system must be able to support different use cases per user role and effectively extract information required by the use cases from various heterogeneous data sources. If the FM system’s user perspective becomes structurally fixed when developing the system, the lack of expandability can cause problems for maintenance and reusability. BIM perspective definition (BPD) metadata helps increase expandability and system reusability because it supports system variability, which allows adding or changing the user perspective even after the system has been developed. The information to be dealt with differs according to the user’s role, which also means that the data model, data conversion rules, and expression methods change per perspective. The perspective should be able to extract only the user-requested data from the heterogeneous system’s data source and format it in the style demanded by the user. In order to solve such issues, we analyzed the practice of FM and the benefits of using BIM-based FM, and we proposed a BPD that supports data extraction and conversion and created a prototype. 相似文献
5.
Te-Hsun Wang Author Vitae Author Vitae 《Pattern recognition》2009,42(5):962-977
This study presents a facial expression recognition system which separates the non-rigid facial expression from the rigid head rotation and estimates the 3D rigid head rotation angle in real time. The extracted trajectories of the feature points contain both rigid head motion components and non-rigid facial expression motion components. A 3D virtual face model is used to obtain accurate estimation of the head rotation angle such that the non-rigid motion components can be precisely separated to enhance the facial expression recognition performance. The separation performance of the proposed system is further improved through the use of a restoration mechanism designed to recover feature points lost during large pan rotations. Having separated the rigid and non-rigid motions, hidden Markov models (HMMs) are employed to recognize a prescribed set of facial expressions defined in terms of facial action coding system (FACS) action units (AUs). 相似文献
6.
点模式匹配是计算机视觉和模式识别领域中的一个重要问题 .通过研究 ,在假定待匹配的两个点模式中已知有三对点整体对应的前提下 ,基于射影坐标以及对投影变换和排序变换同时保持不变的 p2 -不变量等理论 ,通过定义一种广义距离 ,给出了一种求解透视变换下 ,点数不等的两个平面点模式匹配问题的新算法 .理论分析和仿真实验表明 ,该算法是快速、有效的 相似文献
7.
点模式匹配是计算机视觉和模式识别领域中的一个重要问题。通过研究,在假定待匹配的两个点模式中已知有三对点整体对应的前提下,基于射影坐标以及对投景变换和排序变换同时保持不变的p^2--不变量等理论,通过定义一种广义距离,给出了一种求解透视变换下,点数不等的两个平面点模式匹配问题的新算法。理论分析和仿真实验表明,该算法是快速、有效的。 相似文献
8.
Currently, standards for web services are being developed via three different initiatives (W3C, Semantic web services and
ebXML). To the best of our knowledge, no theoretical perspectives underlie these standardization efforts. Without the benefit
of a strong theoretical basis, the results, within and across these initiatives, have remained piecemeal. We suggest ‘Language–Action
Theories’ as a plausible perspective that can effectively define, assess and refine web services standards. In this paper,
we first investigate the existing initiatives to identify commonalities that point to theories of ‘Language–Action’ as an
appropriate theoretical basis for web services standards. Next, we adapt work from these theories to develop a comprehensive
reference framework for understanding web services standards. Finally, we use this reference framework to assess the three
initiatives, and analyze the findings to provide insights for future development and refinement of web services standards.
相似文献
Sandeep PuraoEmail: |
9.
《国际计算机数学杂志》2012,89(1):121-132
Many natural and man-made objects have planar and curvilinear surfaces. The images of such curves do not usually have sufficient distinctive features to apply conventional feature-based reconstruction algorithms. In this paper, we describe a method for the reconstruction of various kinds of quadratic curves in 3D space as an intersection of two cones containing the respective projected digitized curve images in the presence of Gaussian noise. The advantage of this method is that it overcomes the correspondence problem that occurs in pairs of projections of the curve. Using nonlinear least-squares curve fitting, the parameters of a curve in 2D digitized image planes are determined. From this we reconstruct the 3D quadratic curve. Relevant mathematical formulations and analytical solutions for obtaining the equation of the reconstructed curve are given. Simulation studies have been conducted to observe the effect of noise on errors in the process of reconstruction. Results for various types of quadratic curves are presented using simulation studies. These are the main contributions of this work. The angle between the reconstructed and the original quadratic curves in 3D space has been used as the criterion for the measurement of the error. The results of this study are useful for the design of a stereo-based imaging system (such as the LBW decision in cricket, the path of a missile, robotic vision, path planning, etc.) and for the best reconstruction with minimum error. 相似文献
10.