TV bands are candidates for unlicensed spectrum access based on cognitive radio (CR) devices. However, for a successful dynamic spectrum access regime in TV bands, any new unlicensed devices need to ensure that they d...
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TV bands are candidates for unlicensed spectrum access based on cognitive radio (CR) devices. However, for a successful dynamic spectrum access regime in TV bands, any new unlicensed devices need to ensure that they do not interfere with the incumbent devices such as TV receivers and wireless micro phones in these bands. This paper presents models for carrying out interference analysis of CR devices to wireless microphones. The wireless microphone systems are more susceptible to interference by CR devices compared to TV receivers due to their lower power and use of randomly selected idle TV bands at a given location. We present two models for interference, a single interferer model that determines the unlicensed device characteristics needed to protect a wireless microphone system from interference, and a multiple interferers model that provides a measure of the maximum density of unlicensed devices that can operate in a given region without affecting wireless microphone systems. We further analyze the benefits of cooperative sensing among CR devices using the multiple interferers model. Lastly, we provide recommendations for reducing interference based on the two interference models.
There is no doubt that in today's world, the transition from wired to wireless networking and communications is proceeding at a remarkable pace. However, due to the wireless nature of communications, special care ...
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ISBN:
(纸本)9781605606170
There is no doubt that in today's world, the transition from wired to wireless networking and communications is proceeding at a remarkable pace. However, due to the wireless nature of communications, special care must be taken not only to secure the transactions but also to authenticate them. Various authentication protocols are in use today, that provide high level of security but at the same time are resource and power intensive. Due to limited available battery power in PDA's, it is crucial to minimize power consumption in wireless mobile units while still maintaining the same level of security. The aim of this paper is to implement Extensible Authentication Protocol - Tunneled Transport Layer Security (EAP-TTLS), a power and resource efficient authentication handshake protocol while still maintaining the same level of security. For this purpose, the various authentication handshake protocols were first studied and compared before selecting EAP-TTLS protocol. The protocol was implemented on Field programmable Gate Array (FPGA), and was incorporated as a part of the hardware based wireless security system prototype that has been developed within the framework of 802. Hi specifications.
Unmanned vehicle is future vehicle technology. Lateral control technology and longitudinal control technology are needed for unmanned vehicle. Automatic steering system is lateral control technology. A automatic steer...
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In this paper, we tackle robust human pose recognition using unlabelled markers obtained from an optical marker-based motion capture system. A coarse-to-fine fast pose matching algorithm is presented with the followin...
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In this paper, we tackle robust human pose recognition using unlabelled markers obtained from an optical marker-based motion capture system. A coarse-to-fine fast pose matching algorithm is presented with the following three steps. Given a query pose, firstly, the majority of the non-matching poses are rejected according to marker distributions along the radius and height dimensions. Secondly, relative rotation angles between the query pose and the remaining candidate poses are estimated using a fast histogram matching method based on circular convolution implemented using the fast Fourier transform. Finally, rotation angle estimates are refined using nonlinear least square minimization through the Levenberg-Marquardt minimization. In the presence of multiple solutions, false poses can be effectively removed by thresholding the minimized matching scores. The proposed framework can handle missing markers caused by occlusion. Experimental results using real motion capture data show the efficacy of the proposed approach.
In order for solid state lighting technology to become a mainstream technology, one of the major challenges to overcome is increasing the efficiency of these devices while maintaining a proper color balance. A signifi...
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For the past several years, we have, through panel discussions and presentations, been engaged in exploring how to encourage diversity in graduate engineering education. While the percentages of women and minorities e...
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For the past several years, we have, through panel discussions and presentations, been engaged in exploring how to encourage diversity in graduate engineering education. While the percentages of women and minorities earning engineering graduate degrees are increasing, they still (except for women at the masters' level) lag behind the percentages earning bachelor's degrees. A diverse graduate population is important because engineers with graduate training will be at the forefront of leadership and change, in both aeademia and industry, as we confront the many ways in which we will need to make creative use of technology in the coming years. Participants in these discussions have included university faculty and staff and industry representatives. Our discussions have clarified some of the obstacles to diversifying the graduate population, including lack of mentoring and constructive advice, lack of a community for graduate students at a particular institution, and unwritten rules and assumptions which can affect graduate student admission and overall success. In this presentation we review the literature on diversity in graduate education and we describe, for each group of stakeholders in the process of graduate education, policies and activities that have been presented in the literature and that have emerged during our discussions that can help to overcome some of these obstacles. We discuss initiatives that can be carried out effectively by individuals or small groups, initiatives that can be supported by industry and by other groups external to the university, and initiatives that require institutional support. Not surprisingly, successful projects draw support from several of these groups. Major stakeholders who can affect graduate education at an individual institution include individual graduate students, student organizations, and supportive corporate sponsors. Major stakeholders who could help with institutionalization include not only university and college
DNA microarrays provide such a huge amount of data that unsupervised methods are required to reduce the dimension of the data set and to extract meaningful biological information. This work shows that Independent Comp...
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ISBN:
(纸本)9783540737490
DNA microarrays provide such a huge amount of data that unsupervised methods are required to reduce the dimension of the data set and to extract meaningful biological information. This work shows that Independent Component Analysis (ICA) is a promising approach for the analysis of genome-wide transcriptomic data. The paper first presents an overview of the most popular algorithms to perform ICA. These algorithms are then applied on a microarray breast-cancer data set. Some issues about the application of ICA and the evaluation of biological relevance of the results are discussed. This study indicates that ICA significantly outperforms Principal Component Analysis (PCA).
Visual surveillance with dynamic background is one of the most active research topics in computer vision. Especially, researches for abandoned detection in the public place have been caused by preventing terror and ac...
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Visual surveillance with dynamic background is one of the most active research topics in computer vision. Especially, researches for abandoned detection in the public place have been caused by preventing terror and accident. Previous researches for abandoned detection have been based on a static image and used an image difference. In this paper we present an algorithm for a mobile robot and we use optical flow for detecting a static object and distances from abandoned objects. For this purpose, we find abandoned objects and predict a position of objects using a mobile robot visual system with a single camera.
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