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Hai-Cheng Chu Szu-Wei Yang Ching-Hsien Hsu Jong Hyuk Park 《Multimedia Tools and Applications》2014,71(1):219-234
Unquestionably, networked multimedia smart devices are commonly adopted in contemporary ubiquitous wireless computing era with unprecedented evolving pace in terms of mobility, portability, and pervasiveness. Regrettably, those technology-oriented gadgets are phenomenally exploited by cyber criminals or get involved in computer-related incidents unknowingly. Substantively, the detection, prevention, and the related digital forensics of the above scenarios are becoming tremendously urgent both in public and private sectors. Therefore, in this research, we investigate the scenario when state-of-the-art wireless communication technologies are integrated with the networked smart devices where digital evidences may exist and they could be disclosed when appropriate standard operating procedures are suitably applied. Accordingly, in this paper, a PDA with the built-in GPS navigation functionality via the ubiquitous Wi-Fi connection to a popular social networking platform (facebook) is cross examined concerning the related digital evidence collecting and discovering in terms of revealing previous facebook user accounts on the mobile device without shutting off the power. The research provides a generic framework for the digital forensics specialists to contemplate when the networked smart devices are involved in the related criminal investigation cases especially when omnipresent social networking platforms are becoming the new avenue for the escalating, stringent, and heinous cybercrimes. 相似文献
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Association Link Network (ALN) is a kind of Semantic Link Network built by mining the association relations among multimedia Web resources for effectively supporting Web intelligent application such as Web-based learning, and semantic search. This paper explores the Small-World properties of ALN to provide theoretical support for association learning (i.e., a simple idea of “learning from Web resources”). First, a filtering algorithm of ALN is proposed to generate the filtered status of ALN, aiming to observe the Small-World properties of ALN at given network size and filtering parameter. Comparison of the Small-World properties between ALN and random graph shows that ALN reveals prominent Small-World characteristic. Then, we investigate the evolution of Small-World properties over time at several incremental network sizes. The average path length of ALN scales with the network size, while clustering coefficient of ALN is independent of the network size. And we find that ALN has smaller average path length and higher clustering coefficient than WWW at the same network size and network average degree. After that, based on the Small-World characteristic of ALN, we present an Association Learning Model (ALM), which can efficiently provide association learning of Web resources in breadth or depth for learners. 相似文献
78.
Xuan Wang 《Asian journal of control》2014,16(6):1713-1725
Fault occurrence can be embodied by the physical parameter variations of the hydraulic servo system. Faults can, therefore, be diagnosed according to the model coefficient variations of the hydraulic servo system. This paper proposes an approach for fault diagnosis based on the unscented Kalman filter (UKF) with a mathematical model of the hydraulic servo system. The mathematical model is established using the dynamic equations of the hydraulic servo system. Based on the fault mechanism analysis results, several important system model parameters that can separately represent different faults in different components of the hydraulic servo system are chosen. Discrete state space equations are derived from the dynamic equations. The UKF algorithm is used to estimate the important system model parameters of the hydraulic servo system by utilizing the discretized state space model. According to the variations of these model parameters, the fault modes and locations of the hydraulic servo system can be diagnosed and isolated. Two types of faults, namely, abrupt fault in servovalve gain and slow wear fault in hydraulic cylinder piston, which cannot be directly detected from the system output, are introduced individually to the hydraulic servo system in this work. By comparing with the extended Kalman Filter, three different experimental cases are used to validate the effectiveness of the UKF for hydraulic servo system fault diagnosis. 相似文献
79.
点击劫持通过欺骗用户点击经过伪装的界面元素达到攻击目的。移动互联网环境下,智能手机的屏幕特征、手势识别、HTML5支持度高等特性成为点击劫持新的利用点。深入分析并实验验证智能手机脆弱特性,在此基础上提出点击劫持在智能手机上的潜在攻击方案。进而设计并实现一套有针对性的检测方案。该方案从静态页面和动态行为两个角度提取攻击特征,并进行基于规则的量化评估与组合判定。实验结果表明该方案可以有效地降低传统页面特征检测方案的漏报和误报情况。 相似文献
80.
IPv6/IPv4共存环境下多址同源识别是共存网络管理与拓扑发现的一个关键问题。现有研究主要集中于子网内部的双栈发现及单一IP协议栈中的别名解析,难以识别远程IPv6/IPv4共存网络中的多址同源。通过分析同源地址间的本质联系,提出一种IPv6/IPv4多址同源识别模型(SSI),该模型综合利用特殊地址格式匹配、TCP时钟指纹比对和上层协议短时致瘫等多种方式来提高同源地址的识别能力。实验结果表明,上述方法均可有效识别IPv6/IPv4多址同源;SSI模型具有较理想的识别率和正确率。 相似文献