In this paper, we present a timing synchronization scheme of the next generation IEEE 802.11n wireless LAN standard which is based on MIMO-OFDM technique. The proposed timing synchronization method takes two steps whi...
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A novel digital redesign of the analog model-reference-based decentralized adaptive controller is proposed for the sampled-data large scale system consisting of N interconnected linear subsystems with actuator faults....
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ISBN:
(纸本)9780889867468
A novel digital redesign of the analog model-reference-based decentralized adaptive controller is proposed for the sampled-data large scale system consisting of N interconnected linear subsystems with actuator faults. The adaptation of the analog controller gain is derived by using the model-reference adaptive control theory based on Lyapunov method. In this paper, it is shown that the sampled-data decentralized adaptive controlsystem is theoretically possible to asymptotically track the desired output with a specified performance even when actuator faults occur. Then, a method of actuator fault recovery is proposed. With the estimated faults, one can use the proposed input compensation method to solve actuator faults. In this paper, we also introduce a prediction-based digital redesign method to develop the corresponding sampled-data controller for the sampled-data decentralized adaptive controlsystems.
In both industrial and research areas of electronic engineering,Sound Source Localization for robot control has always been an interesting subject to be further *** some dangerous situation,especially when a special d...
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In both industrial and research areas of electronic engineering,Sound Source Localization for robot control has always been an interesting subject to be further *** some dangerous situation,especially when a special driver is required to implement a particular task,the device should be able to combine robotics control technology with Sound Source Localization,and take actions according to the different response *** this research project,a multifunc-tional model driver,named "Mobile Island",has been designed and built up by integrating the Emulator 8051 micro-controller,Intel 8255 interfaces,some components and other necessary *** intelligent Mobile Island imple-mented by C language programs can operate under three control *** the sound control Mode 1,the model driver can detect and track a target by Sound Source Localization and then turn and move toward the *** the keypad control Mode 2,it can be controlled by a manual *** the free run Mode 3,Mobile Island can move and turn by *** finding an object in front,it will turn away before moving forward again,so that it can avoid crashing on the obstacle.
In conventional signature analysis, faulty units are identified by mismatch between the actual and reference signatures. The amount of reference signatures can be quite large for a complex system that requires high te...
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In conventional signature analysis, faulty units are identified by mismatch between the actual and reference signatures. The amount of reference signatures can be quite large for a complex system that requires high testing resolution. This complicates the diagnosis procedure. We show how under certain restrictions this amount can be reduced, preserving the diagnosis resolution and the aliasing rate. We construct a signature analyzer that is capable of locating faulty units. If the analyzer is implemented in the external automated test equipment, its throughput requirements can be diminished.
Data availability is a challenging issue for large- scale cluster file systems built upon thousands of individual storage devices. Replication is a well-known solution used to improve data availability. However, how t...
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Data availability is a challenging issue for large- scale cluster file systems built upon thousands of individual storage devices. Replication is a well-known solution used to improve data availability. However, how to efficiently guarantee replicas consistency under concurrent conflict mutations remains a challenge. Moreover, how to quickly recover replica consistency from a storage server crash or storage device failure is also a tough problem. In this paper, we present a replication-based data availability mechanism designed for a large-scale cluster file system prototype named LionFS. Unlike other replicated storage systems that serialize replica updates, LionFS introduces a relaxed consistency model to enable concurrent updating all replicas for a mutation operation, greatly reducing the latency of operations. LionFS ensures replica consistency if applications use file locks to synchronize the concurrent conflict mutations. Another novelty of this mechanism is its light-weight log, which only records failed mutations and imposes no overhead on failure-free execution and low overhead when some storage devices are unavailable. Furthermore, recovery of replica consistency needs not stop the file system services and running applications. Performance evaluation shows that our solution achieves 50-70% higher write performance than serial replica updates. The logging overhead is shown to be low, and the recovery time is proportional to the amount of data written during the failure.
Survivability and reliability are critical for the operation of shipboard power system both in normal and damage conditions. This paper presents a novel dynamic reconfiguration approach for shipboard power system by u...
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Survivability and reliability are critical for the operation of shipboard power system both in normal and damage conditions. This paper presents a novel dynamic reconfiguration approach for shipboard power system by using multi-agent system. With the similar topology of the shipboard power system, the multi-agent system is generalized to constraint satisfaction problem (CSP). The environment- reactive rules-agents (ERA) approach, which is multi-agent oriented, is used to support the organization formation behavior in dynamic reconfiguration. The effectiveness of the proposed approach is illustrated by test results in a reduced shipboard power system.
E-learning content creation is not an easy task, but its evaluation is even more complex. In order to evaluate if the content is adequate to the studentspsila needs, it would be helpful to know how the student assimil...
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E-learning content creation is not an easy task, but its evaluation is even more complex. In order to evaluate if the content is adequate to the studentspsila needs, it would be helpful to know how the student assimilated the learning content, how he/she reacted to it and the period of time spent on the learning object. Besides, considering the different cognitive features of learning and the possibility of adjusting the didactic content, it could help teacherpsilas evaluation in an available online course. This work describes a monitoring system (Msys) able to track the level of utilization of studentpsilas activities, and presents summarized and comparative results to the teacher and to the student. This paper describes how the MSys tool was created using current standards on digital content construction, defining functional requirements of interface to its development, presenting a proof-of concept and how it could be integrate to online learning systems, providing benefits to the teacherpsilas evaluation.
The problem of vehicle detection and segmentation in outdoor scenes is tackled. Vehicle shadows pose problems in vehicle segmentation step. In this paper, it is proposed to employ temporal edge density information as ...
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The problem of vehicle detection and segmentation in outdoor scenes is tackled. Vehicle shadows pose problems in vehicle segmentation step. In this paper, it is proposed to employ temporal edge density information as prior knowledge to distinguish moving vehicle from moving shadow and background in a traffic surveillance system. Experimental results showed good moving vehicle segmentation performance. The proposed approach is currently limited to free-flowing traffic scenes.
In this paper, we present a timing synchronization scheme of the next generation IEEE *** wireless LAN standard which is based on MIMO-OFDM technique. The proposed timing synchronization method takes two steps which c...
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In this paper, we present a timing synchronization scheme of the next generation IEEE *** wireless LAN standard which is based on MIMO-OFDM technique. The proposed timing synchronization method takes two steps which consist of two modified auto-correlators. For coarse timing synchronization, a sliding window differentiator is used after a conventional auto-correlation in order to avoid plateau problem. The conjugate symmetry property of L-LTS is used for fine timing synchronization. Since cross-correlation based methods are not required, the computational complexity and the number of multiplier can be reduced. In order to reduce the hardware complexity, we have used sign comparators (SC) instead of using multipliers. Based on simulation results, the proposed method outperforms a conventional method. The proposed scheme can be applied to IEEE 802.1 In systems and can easily be expanded to frequency synchronization scheme.
In many cases, protein mass-spectrometry data are imbalanced, i.e. the number of positive examples is much less than that of negative ones, which generally degrade the performance of classifiers used for protein recog...
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In many cases, protein mass-spectrometry data are imbalanced, i.e. the number of positive examples is much less than that of negative ones, which generally degrade the performance of classifiers used for protein recognition. Despite its importance, few works have been conducted to handle this problem. In this paper, we present a new method that utilizes the EasyEnsemble algorithm to cope with the imbalance problem in mass-spectrometry data. Furthermore, two feature selection algorithms, namely PREE (Prediction Risk based feature selection for EasyEnsemble) and PRIEE (Prediction Risk based feature selection for Individuals of EasyEnsemble), are proposed to select informative features and improve the performance of the EasyEnsemble classifier. Experimental results on three mass spectra data sets demonstrate that the proposed methods outperform two existing filter feature selection methods, which prove the effectiveness of the proposed methods.
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