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In the Internet of Things (IoT) smart objects are able to provide or require specific services. The goal of this work is to identify malicious behavior of nodes performing selective attacks. In this type of attacks the nodes selectively decide what kind of service they will provide to the network, in order to save resources. We use a trust management model to detect such behavior. We perform network...
Wearable devices are becoming very popular. They are present in sports, general activities, everyday life, etc. generating gradually new data. However, few applications are benefited by this new flood of data. This paper suggests an application based on data generated by wearable devices, which could result in significant improvement to better understand the individual and his life conditions. In...
People with disabilities usually face difficulties during travel in aircrafts. Among these difficulties, there are limitations while seated during the journey. The seat and console controls may be hard to reach and use or not accessible at all. Considering the trend of airliners to allow the usage of wireless devices during flights, personal mobile devices become an option for improving comfort and...
This paper presents an approach combining concepts such as Internet of Things (IoT) and Cloud Computing to create digital assistive technology focused on the urban space context. We propose the convergence of Smart City, Urban Computing, Accessibility and Universal Design in order to provide a citizen experience of independence and autonomy in the city for a range of people that frequently depend...
This paper presents a pipelined fast Fourier transform (FFT) processor consisting of radix-2, 3 and 5 for prime-sized discrete Fourier transform (DFT). The FFT processor does not require memory storing the twiddle factors or complex multiplications. It is adaptable for 34 kinds of the FFT length with a trivial multiplications and multiplexing of data in the LTE uplink. The proposed architecture reduces...
This paper presents fully parallel fast Fourier transform (FFT) processor for coherent optical OFDM system. It has a length of 256. For processing of 100 Gb/s throughput it has parallel input and output structure. FFT processor has 32 radix-16 processor with trivial multiplication and consists of an array structure in parallel arithmetic processing. We designed and implemented the proposed FFT processor...
Terrestrial TV stations make up networks that may have regional or national coverage, far away from the local coverage feature in which they were proposed. In this context, we analyze the impact of these networks on the experience of the user has to watch TV, since the variety of channels available through local and global content, and, finally, evaluating the spectator's expectations regarding the...
Almost all of the wireless devices are supplied by chemical batteries. These batteries have a number of disadvantages. In this study, a broadband RF energy harvester was designed to providing the use of wireless devices without batteries or increasing battery life. The system is designed to work between 500 MHz and 900 MHz. Thus, the proposed system can be obtained electrical energy from both DTV...
Recently, Light Emitting Diode (LED) projectors have been widely adopted by consumers. These low-cost compact projectors provide high-brightness and high-resolution images. In addition, the LED bias current can be incrementally adjusted individually for each color LED, i.e. Red, Green, and Blue, which allow a more accurate tuning capability than in traditional light bulb projectors. The variation...
Viewing quality assessment is important in every phase of coder development and deployment, and also in the design and operation of video streaming services. In the development and design phases an objective metric is more cost-effective and less time-consuming than a subjective assessment. The behavior of the impairment caused by packet-delay-variation (PDV) over quality inspires the conception of...
Ultraviolet radiation from the Sun is an essential part of the process of obtaining Vitamin D by the human body. However, prolonged exposure poses a risk to the health of the skin and eyes that can lead to premature aging and even cancer. Moreover, the quick technological development shows some barriers for visually impaired users because they require special help via audio devices, in order to access...
This study evaluates a large Profinet network using ring topology applied in an industry production line. The analysis is based on some performance indicators: jitter and throughput taking in consideration the update time of the devices, number of switches and cable length between IO-Devices and the IO-Controller. The network studied has a considerable amount of devices including distributed IOs,...
This article aims to present a mobile application to remotely optimize the use of household appliances in a home based on the dynamic variation of electricity price throughout the day. The customer defines the limits of hourly consumption and the use time interval of each appliance throughout the day in the mobile application, and it communicates with Matlab software installed on a computer to perform...
This project aims to develop a yaw controller system for a CubeSat prototype, which tracks a remote set point signal. This prototype is oriented to education and entertainment in aerospace technologies. Aiming to reducing the costs, commercial off-the-shelf devices (COTS) were used. Thus, a Atmel 8-bit AVR microcontroller was utilized for computational work, a couple of 2.4GHz transceiver for communication...
The lack of interactivity seems to be one of the most common problem in distance learning. In this context, this study proposes an e-learning platform based on IMS infrastructure that is able to improve the interaction among students and instructors. The interactivity offered by the proposed scheme was considered 65% equal or better than the live class, demonstrating how efficient this kind of technology...
This paper presents a mechanism to provide a real-time assessment of voice quality on mobile handled devices. This solution considers the voice degradations caused by the radio frequency channel and packet losses on the IP network. Furthermore, the network architecture of the proposed solution is introduced and the application is implemented on the user mobile device.
Wireless Ad-Hoc Networks (WANETs) need algorithms and protocols that may provide higher packet delivery throughput for non-structured networks with a high degree of mobility. Moreover, the possibility of reducing the broadcasting packages that will heavily consume power resources on nodes is extremely important. This paper studies the implementation of a modification in the epidemic algorithm, a direction-biased...
Production lines normally present a verification step, which is responsible for warning about defective devices. That step, in digital television (DTV) production lines, often includes a tuning and decoding check, which basically verifies if DTV devices are capable of presenting audio and video. However, poor signal conditions may cause unnecessary rejections, which happen due to very hostile environments...
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