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Artificial Life and Robotics - The aging population and expectations for nursing care robots increased significantly recently. We focused on mobile assistive robots. When various types of robots... 相似文献
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Mobile Networks and Applications - Artificial fish swarm algorithm (AFS) is used in the field of function optimization problems widely. The traditional AFS algorithm has some problems such as long... 相似文献
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In many applications, it is desired to dynamically establish temporary multicast groups for secure message delivery. It is also often the case that the group membership information itself is sensitive and needs to be well protected. However, existing solutions either fail to address the issue of membership anonymity or do not scale well for dynamically established groups. In this paper, we propose a highly scalable solution for dynamical multicast group setup with group membership anonymity. In the proposed solution, scalability and membership anonymity are achieved via a novel design that integrates techniques such as ciphertext-policy attribute-based encryption (CP-ABE). In our design, multicast groups are specified through group member attributes. As these attributes are potentially able to be shared by unlimited number of group members, our proposed scheme scales well. Also, high level of membership anonymity is guaranteed such that every group member knows nothing but his own group membership only. The complexity of our proposed scheme in terms of computational overhead and ciphertext size is O(n), where n is the number of attributes and independent to the group size. 相似文献
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Squeeze-film damping on microresonators is a significant damping source even when the surrounding gas is highly rarefied. This article presents a general modeling approach based on Monte Carlo (MC) simulations for the prediction of squeeze-film damping on resonators in the free-molecule regime. The generality of the approach is demonstrated in its capability of simulating resonators of any shape and with any accommodation coefficient. The approach is validated using both the analytical results of the free-space damping and the experimental data of the squeeze-film damping on a clamped–clamped plate resonator oscillating at its first flexure mode. The effect of oscillation modes on the quality factor of the resonator has also been studied and semi-analytical approximate models for the squeeze-film damping with diffuse collisions have been developed. 相似文献
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提出了基于LabVIEW和MATLAB混合编程的虚拟式语音信号采集、分析与识别平台设计方案;该平台通过PC机声卡完成对语音信号的实时采集和回放,并对语音信号进行时频分析、端点检测和倒谱分析,进而实现语音识别;为提高识别的正确性和灵活性,提出孤立字列举识别算法和词库编码连续语音识别算法;结果表明,两种算法都能有效识别同音字和读音相似的字;其中,词库编码识别算法不仅效率高,还具有一定的纠错能力,更具有应用价值. 相似文献
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Though the network quality-of-service (QoS) metrics are defined in terms of technical parameters (e.g., delay, jitter, bandwidth), they are rather subjective when it comes to the end user. Oftentimes, the end user finds it difficult to express his desired QoS in such technical parameters, though he has a fair idea of what QoS he desires. In this paper, we show how translation functions can be devised and used to translate the user inputs to networking parameters that are used by various layers of the protocol stack. In particular, we consider an ad hoc network and show an interface design that uses translation functions to map user supplied inputs to parameters at the medium access control (MAC) and routing layers. These parameters, in turn, choose the right strategies that particular layer functionality can adopt, such that the QoS desired by the user is achieved. We also compute the associated costs due to the different strategies adopted. We implement the interface on ns-2 and conduct simulation experiments with randomly scattered IEEE 802.11 enabled nodes. Results show the functionality of the interface and demonstrate how delay, throughput, and network lifetime are affected when the end user seeks different levels of QoS. 相似文献
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马文静 《可编程控制器与工厂自动化(PLC FA)》2006,(10):101-103
本文介绍济钢的中置式封闭开关柜运行环境监控系统,解决了因为没有先进有效的监控手段,避免了封闭开关柜因为通风散热差而引起设备事故的发生。 相似文献