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991.
We consider a problem of finding a path of an unmanned combat vehicle that patrols a given area by visiting a given set of checkpoints with the objective of minimizing possibility of enemy’s infiltration. In this study, we focus on a situation in which the possibility of enemy’s infiltration at (through) each checkpoint is increased nonlinearly as time passes and the checkpoint may be patrolled multiple times during a planning horizon. We develop two-phase heuristics in which an initial path is constructed in the first phase and then it is improved in the second phase. For evaluation of the performance of the proposed heuristics, computational experiments are performed on randomly generated problem instances, and results show that the heuristics give good solutions in a reasonably short time. 相似文献
992.
Social media services such as YouTube and Flickr have become online necessities for millions of users worldwide. Social media are online services that enable users to share contents, opinions, and perspectives that support communication with other users. Social media places an emphasis on the shared experience between users, which we call co-experience. However, the online characteristics of social media increase psychological distance between users, which, in turn, results in a decrease in the quality of co-experience. Hence, as the goal of this study, we theoretically modeled and empirically verified the antecedents and user experience-based consequences of psychological distance in a social media-enhanced real-time streaming video service. In order to reduce psychological distance, we introduced two system elements: inhabited space (the degree of being situated in context and in a meaningful place) and isomorph effects (the degree of preserving the structure of a user’s actions). We constructed a social media-enhanced real-time streaming video service prototype and conducted a field experiment with actual social media users. The prototype, which streamed a live baseball game, enabled users to simultaneously view the game from remote locations and to interact with each other through cheering tools. The results indicate that inhabited space and isomorph effects reduce psychological distance between users, and this, in turn, enhances co-experience. This paper ends with theoretical as well as practical implications of the study. 相似文献
993.
Hyperspectral band selection aims at the determination of an optimal subset of spectral bands for dimensionality reduction
without loss of discriminability. Many conventional band selection approaches depend on the concept of “statistical distance”
measure between the probability distributions characterizing sample classes. However, the maximization of separability does
not necessarily guarantee that a classification process results in the best classification accuracies. This paper presents
a multidimensional local spatial autocorrelation (MLSA) measure that quantifies the spatial autocorrelation of the hyperspectral
image data. Based on the proposed spatial measure, a collaborative band selection strategy is developed that combines both
spectral separability measure and spatial homogeneity measure for hyperspectral band selection without losing the spectral
details useful in classification processes. The selected band subset by the proposed method shows both larger separability
between classes and stronger spatial similarity within class. Case studies in biomedical and remote sensing applications demonstrate
that the MLSA-based band selection approach improves object classification accuracies in hyperspectral imaging compared with
conventional approaches. 相似文献
994.
Sangseok Yun Bongjin Jun Daijin Kim Jaewoong Kim Sukhan Lee Mun-Taek Choi Munsang Kim Joong-Tae Park Jae-Bok Song 《Journal of Intelligent and Robotic Systems》2012,67(2):79-99
This paper describes a scheme for proactive human search for a designated person in an undiscovered indoor environment without human operation or intervention. In designing and developing human identification with prior information a new approach that is robust to illumination and distance variations in the indoor environment is proposed. In addition, a substantial exploration method with an octree structure, suitable for path planning in an office configuration, is employed. All these functionalities are integrated in a message- and component-based architecture for the efficient integration and control of the system. This approach is demonstrated by succeeding human search in the challenging robot mission of the 2009 Robot Grand Challenge Contest. 相似文献
995.
Mande XieAuthor Vitae Guiyi WeiAuthor VitaeYujia GeAuthor Vitae Yun LingAuthor Vitae 《Computers & Electrical Engineering》2012,38(1):116-127
This paper proposes two algorithms for multi-video-source in a new mobile P2P architecture for streaming media systems. One is serial, and the other is parallel. When the service peer set providing expected QoS is not empty, the former is called, otherwise the latter is called. The former triggers the video source change event, re-selects a video source, and synchronizes the multi-video-source by the time model of the streaming sequence when QoS is degraded. The latter allows the multiple video sources to concurrently send the data to the receiving peer according to the assigned transmission. Compared to the existing papers, the contribution of this paper is fourfold: (1) the serial and parallel scheduling algorithms, correctly switched according to the actual situation, are firstly proposed; (2) the mobile feature of peers are firstly considered and validated; (3) the client nodes have better and smoother video quality; (4) our algorithms have shorter run time, which is a crucial factor for an on-line system. 相似文献
996.
Automatic Real-Time Video Matting Using Time-of-Flight Camera and Multichannel Poisson Equations 总被引:1,自引:0,他引:1
Liang Wang Minglun Gong Chenxi Zhang Ruigang Yang Cha Zhang Yee-Hong Yang 《International Journal of Computer Vision》2012,97(1):104-121
This paper presents an automatic real-time video matting system. The proposed system consists of two novel components. In
order to automatically generate trimaps for live videos, we advocate a Time-of-Flight (TOF) camera-based approach to video
bilayer segmentation. Our algorithm combines color and depth cues in a probabilistic fusion framework. The scene depth information
returned by the TOF camera is less sensitive to environment changes, which makes our method robust to illumination variation,
dynamic background and camera motion. For the second step, we perform alpha matting based on the segmentation result. Our
matting algorithm uses a set of novel Poisson equations that are derived for handling multichannel color vectors, as well
as the depth information captured. Real-time processing speed is achieved through optimizing the algorithm for parallel processing
on graphics hardware. We demonstrate the effectiveness of our matting system on an extensive set of experimental results. 相似文献
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显微结构定量分析系统是集古瓷釉显微结构图的图像分析,数据提取及数据库管理于一体,可以满足用户的基本需求.系统中运用了体视学基本原理,提取出了陶瓷结构的二维基本数据,从而可以进一步得到三维普适参量,以达到对分析结构的特征重建目的. 相似文献