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991.
In the service-oriented computing paradigm, cross-organizational applications and information systems can be built upon services from different providers. Services are subject to changes required by the organizational and regulatory policies changes. The challenging problem of service change management has been studied actively in recent years. This paper provides an extensive overview of the current research on change management in the context of service-oriented computing. First, we classify service changes into three major types as interface, behavioral, and non-functional changes. Then, we review the existing work on change management from the four broad categories: Service Adaptation, Process Flexibility, Service Evolution, and Change Analysis and Management in Service Compositions. In each category, we discuss the focusing changes, the proposed approaches to dealing with the change problems, and the change issues that remain to be solved. 相似文献
992.
在抢救急危重症病人生命、应对自然灾害和突发事件中,救护车发挥着极为重要的作用。然而我国救护车车载装
备仍然比较落后,只能提供最基本的抢救处理。本文从改良急救车装备角度出发,提出在救护车上增设便携式气管插管
系统和呼吸机,为呼吸困难的危重病人快速建立人工气道,最大限度赢得进一步救治的时间和机会,大大提高危重病人
存活率。 相似文献
993.
贾经纬 《网络安全技术与应用》2013,(11):75-75,71
本文根据同一个僵尸网络中的成员在行为上呈现一定相似性的原理,提出了一个僵尸网络检测模型,该模型能满足对IRC、HTTP、P2P三种僵尸网络的检测要求. 相似文献
994.
局域网应用越来越广泛,鉴于网络宽带的有限性,提出了基于精确流量控制的局域网网关出口管理策略,网络出口管理的优化控制得以实现,有效改善了局域网络拥塞问题. 相似文献
995.
Guo‐Zhen Wang Yi‐Pai Huang Tian‐Sheuan Chang 《Journal of the Society for Information Display》2013,21(9):381-388
A camera‐free 3D air‐touch system was proposed. Hovering, air swiping, and 3D gestures for further interaction with the floated 3D images on the mobile display were demonstrated. By embedding multiwavelength optical sensors into the display pixels and adding angular‐scanning illuminators with multiwavelength on the edge of the display, the flat panel can sense images reflected by a bare finger from different heights. In addition, three axis (x, y, z) information of the reflected image of the fingertip can be calculated. Finally, the proposed 3D air‐touch system was successfully demonstrated on a 4‐inch mobile 3D display. 相似文献
996.
Kuo‐Chung Huang Yi‐Heng Chou Lang‐chin Lin Hoang Yan Lin Fu‐Hao Chen Ching‐Chiu Liao Yi‐Han Chen Kuen Lee Wan‐Hsuan Hsu 《Journal of the Society for Information Display》2013,21(6):263-270
The optimal viewing distance was proposed as a parameter for designing a parallax barrier 3D display. It can be designed based on simple geometric method and by considering the pitches of image display pixels and parallax barrier, or even including the aperture ratios of the image display pixels and parallax barrier. It can be analyzed by using ray tracing method. By considering the optical refraction index of the cover glass, the angular behavior of the system becomes more realistic; however, the geometric method is difficult to be used. We propose a revised method for estimating the view distance and angular behavior. In this paper, we have demonstrated a designated eye position (DEP) for each view and shown that multiple DEPs make a circular curve around the center of the display. We prove the new concept by comparing the optical ray tracing calculations and optical measurement. 相似文献
997.
Although client satisfaction surveys can assess client satisfaction with IT service quality, they cannot easily be used to pinpoint how internal IT behaviors influence client satisfaction and prescribe solutions. This research fills the gap by introducing a concept— IT Service Climate—and a validated ten-item instrument that significantly explained client ratings of IT service quality. We recommend this measure as an effective diagnostic tool for managers aiming to improve quality and client satisfaction. 相似文献
998.
Segmentation of the left ventricle (LV) is a hot topic in cardiac magnetic resonance (MR) images analysis. In this paper, we present an automatic LV myocardial boundary segmentation method using the parametric active contour model (or snake model). By convolving the gradient map of an image, a fast external force named gradient vector convolution (GVC) is presented for the snake model. A circle-based energy is incorporated into the GVC snake model to extract the endocardium. With this prior constraint, the snake contour can conquer the unexpected local minimum stemming from artifacts and papillary muscle, etc. After the endocardium is detected, the original edge map around and within the endocardium is directly set to zero. This modified edge map is used to generate a new GVC force filed, which automatically pushes the snake contour directly to the epicardium by employing the endocardium result as initialization. Meanwhile, a novel shape-similarity based energy is proposed to prevent the snake contour from being strapped in faulty edges and to preserve weak boundaries. Both qualitative and quantitative evaluations on our dataset and the publicly available database (e.g. MICCAI 2009) demonstrate the good performance of our algorithm. 相似文献
999.
Shams Qazi Raad Raad Yi Mu Willy Susilo 《Journal of Network and Computer Applications》2013,36(2):582-592
A wormhole attack is one of the hardest problems to detect whereas it can be easily implanted in any type of wireless ad hoc network. A wormhole attack can easily be launched by the attacker without having knowledge of the network or compromising any legitimate nodes. Most existing solutions either require special hardware devices or make strong assumptions in order to detect wormhole attacks which limit the usability of these solutions. In this paper, we present a security enhancement to dynamic source routing (DSR) protocol against wormhole attacks for ad hoc networks which relies on calculation of round trip time (RTT). Our protocol secures DSR against a wormhole attack in ad hoc networks for multirate transmissions. We also consider the processing and queuing delays of each participating node in the calculation of RTTs between neighbors which to date has not been addressed in the existing literature. This work provides two test cases that show that not taking multirate transmission into consideration results in miss identifying a wormhole attack. 相似文献
1000.
Based on the classification rule of sparse representation-based classification (SRC) and linear regression classification (LRC), we propose the maximum nearest subspace margin criterion for feature extraction. The proposed method can be seen as a preprocessing step of SRC and LRC. By maximizing the inter-class reconstruction error and minimizing the intra-class reconstruction error simultaneously, the proposed method significantly improves the performances of SRC and LRC. Compared with linear discriminant analysis, the proposed method avoids the small sample size problem and can extract more features. Moreover, we extend LRC to overcome the potential singular problem. The experimental results on the extended Yale B (YALE-B), AR, PolyU finger knuckle print and the CENPARMI handwritten numeral databases demonstrate the effectiveness of the proposed method. 相似文献