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141.
This paper proposes a fast and robust 3D human face geometric data registration strategy dedicated for image-guided medical
applications. The registration scheme is composed of a coarse transformation stage and a fine-tuning stage. In the first stage,
fuzzy c-mean is used to reduce the data amount of template 3D image, and evolutionary computation is implemented to find optimal
initial pose for the Iterative Closest Point plus k-dimensional (KD) tree scheme. In the second stage, the huge reference
image data are replaced by a Kriging model. The time-consuming search for corresponding points in evaluating the degree of
misalignment is substituted by projecting the points in the template image onto the model. To illustrate the validity and
applicability of the proposed approach, a problem composed of 174 635 points reference image and an 11 280 points template
image is demonstrated. Computational results show that our approach accelerates the registration process from 1361.28 seconds
to 432.85 seconds when compared with the conventional ICP plus K-D tree scheme, while the average misalignment reduces from
11.35 mm to 2.33 mm.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
142.
ZHANG Xiao-hong 《通讯和计算机》2008,5(12):39-43
An online face recognition system is presented in the paper. To online face recognition system, we should consider the recognition rate, the image compression and image size. In the paper we researched the innovation technologies for face recognition system, including Kernel Principal Component Analysis (Kernel PCA), Delta low-pass wavelet filter, and face recognition algorithm using multiple images. Kernel PCA is derived to classify the characteristics of training images in the database. Delta low-pass wavelet filter is used to reduce the image size. A face recognition algorithm using multiple images is presented to improve the recognition rate. Simulation experiment shows that in the case of packet loss recognition rate is improved highly. 相似文献
143.
Mitsuyoshi Nagao Masahito Yamamoto Keiji Suzuki & Azuma Ohuchi 《International Transactions in Operational Research》2001,8(1):31-45
In this paper, we propose a face identification system based on the Mahalanobis–Taguchi System (MTS). The MTS is one of the pattern recognition methods frequently used in quality engineering, and can perform robust pattern recognition by using training data, including noise. It is likely that this advantage will allow the effective implementation of a robust face identification system against lighting and face position fluctuations. Moreover, the MTS can optimize the number of attributes required for identification by using the orthogonal array and the signal/noise (SN) ratio. The face identification system has to deal with many users and the amount of data in a facial image is large. Therefore, the time required for identification can be decreased and the amount of data in the facial image database can be reduced by performing the optimization. We confirmed the effectiveness of the proposed system through practical experiments. The experimental results revealed that the MTS was an effective method for robust face identification, and could effectively reduce the number of attributes required for identification. 相似文献
144.
Detecting and tracking human faces in video sequences is useful in a number of applications such as gesture recognition and
human-machine interaction. In this paper, we show that online appearance models (holistic approaches) can be used for simultaneously
tracking the head, the lips, the eyebrows, and the eyelids in monocular video sequences. Unlike previous approaches to eyelid
tracking, we show that the online appearance models can be used for this purpose. Neither color information nor intensity
edges are used by our proposed approach. More precisely, we show how the classical appearance-based trackers can be upgraded
in order to deal with fast eyelid movements. The proposed eyelid tracking is made robust by avoiding eye feature extraction.
Experiments on real videos show the usefulness of the proposed tracking schemes as well as their enhancement to our previous
approach.
相似文献
Javier OrozcoEmail: |
145.
对逆系统方法作为反馈线性化方法及其非线性本质进行深入的研究后,认知到逆系统方法建立的模糊控制器是一种变增益的非线性控制器,它与PID控制器有许多相似之处,进而设计出模糊PID复合控制器。模糊PID控制器在综放工作面中的应用的关键是模糊控制器的各个参数的整定。因此,我们用传统的方法首先设计一个PID控制器,在稳定时使模糊PID控制器的参数与PID控制器的对应参数相等,逐步调节、修改各个参数,从而可以得出模糊PID控制器的参数,模糊PID控制器在煤矿综放工作面上运用的结果令人满意。 相似文献
146.
康向文 《中国水能及电气化》2013,(12):1-5
普西桥水电站作为阿墨江流域唯一具备年调节功能的最大水电站,采用混凝土面板堆石坝,通过大坝填筑料优化设计,充分利用其余建筑物开挖料,有效降低了工程造价。通过坝体填筑施工实践,摸索出一套行之有效的施工方法及施工工艺。目前大坝已填筑完成80%,正按照明年5月下闸蓄水的目标迈进。 相似文献
147.
根据充填采煤液压支架结构原理及控顶作用,建立了支架顶梁的力学模型,分析得出了顶梁受力情况及3排立柱受力之间的关系;运用Pro/E软件对支架进行三维建模和运动学仿真分析,模拟出主要部件的运动过程,得出各主要部件在工作过程中的运动特征曲线,并对支架参数进行了校核.基于以上分析结果设计制造了ZZC8800/20/38型充填采煤液压支架,支架前、后排立柱受力分别是中立柱支架受力的4.1倍、4.6倍.该支架在平煤十二矿成功应用表明受力分析及设计是科学合理的. 相似文献
148.
超高面板堆石坝设计原则探讨 总被引:3,自引:0,他引:3
目前超高面板坝比较普遍地出现了面板沿垂直缝挤压破坏、顶部水平弯曲裂缝和水平拉伸裂缝等结构性破坏,为了防止这些事故的发生,探讨提出了超高面板坝设计原则。设计原则主要包括主堆石区压缩模量、主堆石区宽度、主次堆石压缩模量比、水库蓄水计划、设置堆石预沉降时间、分区堆石颗粒级配和面板设计等几个方面。 相似文献
149.
150.
Yanhui Huang Xing Zhang Yangyu Fan Lijun Yin Lee Seversky James Allen Tao Lei Weijun Dong 《Image and vision computing》2012
3D face scans have been widely used for face modeling and analysis. Due to the fact that face scans provide variable point clouds across frames, they may not capture complete facial data or miss point-to-point correspondences across various facial scans, thus causing difficulties to use such data for analysis. This paper presents an efficient approach to representing facial shapes from face scans through the reconstruction of face models based on regional information and a generic model. A new approach for 3D feature detection and a hybrid approach using two vertex mapping algorithms, displacement mapping and point-to-surface mapping, and a regional blending algorithm are proposed to reconstruct the facial surface detail. The resulting models can represent individual facial shapes consistently and adaptively, establishing facial point correspondences across individual models. The accuracy of the generated models is evaluated quantitatively. The applicability of the models is validated through the application of 3D facial expression recognition using the static 3DFE and dynamic 4DFE databases. A comparison with the state of the art has also been reported. 相似文献