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In this study, the performance analysis of Fast Fourier Transform and Chirp Z transform based OFDM systems for cognitive radio networks with energy detector model for the spectrum sensing method is realized. Here, energy detection model for noncooperative spectrum sensing is investigated. On the other hand, the analysis is implemented by segmented Chirp z transform. In this study Chirp z transform...
In recent years, most underwater vehicles are equipped with optical cameras to capture underwater images. But underwater images acquired using optic cameras have poor visual quality due to propagation of properties of light in water. So it is useful to apply image enhancement methods to increase visual quality of the images as well as enhance interpretability and visibility. In this paper, an Empirical...
There are many application areas for wireless sensor networks, such as security, health, and emergency. Recent research studies show that, voice over wireless sensor network applications are possible especially for emergency and rescue missions. In this study, by using 6.3 kbps G.723.1 codec, voice over ZigBee wireless sensor networks experiments are made. The results are examined based on packet...
Human action recognition and interpretation constitutes an important part of the video understanding. In this work, a novel action recognition system is developed that uses edge features obtained from optical flow power shapes which is represented as sequential gradient histograms. The presented system can achieve equal results to the complicated top action recognition systems of nowadays. The system...
This paper provides a comparative study on the different techniques of classifying human activities using a tag-based radio-frequency (RF) localization system. Non-uniformly-sampled data containing position measurements of the tags on the body is first converted to a uniformly-sampled one using different curve-fitting algorithms. Then, the data is partitioned into segments. Finally, various classification...
Plants play a crucial role in terms of the lives of human and other creatures since the existence of the universe. Despite the studies of plant scientists, there are many undiscovered and unidentified species in our environment. This paper is aimed to add the leaves, whose images have been clearly attained, to the system and to provide a proper analysis of those leaves. The images could be either...
Infrared (IR) sensors are intensively used in the thermal image processing applications. IR sensors have dominant effects on the performance enhancement of a thermal imaging system. If performance characteristics of IR sensors are known prior to the costly and time-consuming production phase, high performance IR sensors could be obtained rapidly and cost effectively. In this study, performance characteristics...
As the use of multimedia technology increases, its copyright protection and content authentication has become an issue to be addressed. Watermarking is a known technology that can help protect multimedia contents from illegal copying and access protection. Multimedia Watermarking based on discrete wavelet transform, which has been the most widespread technology for securing multimedia, is not shift...
In this study, a general simulation of the European Digital Terrestrial Television Broadcasting standards which are known as “Digital Video Broadcasting - Terrestrial (DVB-T)” and “Second Generation Digital Video Broadcasting - Terrestrial (DVB-T2)” are implemented. The both of the standards are simulated under the effects of Additive White Gaussian Noise (AWGN) Channel and the acquired results are...
In this paper, a wavelet application which aims to monitor a domestic natural gas boiler as a mechanical system is presented. In this predictive maintenance application, discrete-time wavelet decomposition is basically used to analyze the recorded vibration signal of the mechanical system. A low cost microphone is utilized to capture the vibrations. Then a Simulink model of the application is built...
In this paper, an image edge detection technique based on the ant colony system (ACS) is implemented. ACS is one of the many ant algorithms of Ant Colony Optimization (ACO). The number of artificial ants, the total step number for each ant and the size of ant memory used in ACS is determined by applying genetic algorithm. Several reproductions of input image are obtained by nonlinear contrast enhancement...
A novel low complexity feature extraction algorithm, only performing by a single comparison per pixel on the average during detection is proposed. While single-scale version of the algorithm remains quite efficient compared against the complexity of the state-of-the-art algorithms, a multi-scale version is also proposed to handle blur and scale changes. The performance tests on the repeatability of...
Digital audio watermarking is a technique for embedding data within an audio signal in such a way that the original and the modified audio signals are essentially identical. The embedded data can be used for various purposes such as secure communication in military applications, owner identification and verification, content authentication, etc. In this study a watermark audio signal is hidden in...
This paper presents design considerations of a GPS-aided localization system for unmanned vehicles used in outdoor applications. The system proposed in this paper is based on Extended Kalman Filter (EKF) and also integrates Global Positioning System (GPS) measurements. Localization and navigation systems are base components of all unmanned vehicles since they give unmanned vehicles the ability of...
Cooperative underwater acoustic communication systems come into prominence in recent years. Since underwater channels are sparse and additive noise entering the system is colored Gaussian noise. Therefore it is very difficult to estimate the underwater channels and theoretically makes it interesting. In this study, the transmission from source to the target recipient is realized by means of a relay...
Inter-Vehicle Communication (IVC) is a promising technology for the next generation of automotive vehicles. Recent advancements in IVC enabled the use of a wide range of safety and infotainment applications. Due to the fact that practical experiments are often not feasible, simulation of network protocol behavior is preferred. In this paper, we propose an ETSI complaint Geonetworking protocol layer...
In literature, several methods are available to combine both low spatial multispectral and low spectral panchromatic resolution images to obtain a high resolution multispectral image. One of the most common problems encountered in these methods is spectral distortions introduced during the merging process. At the same time, the spectral quality of the image is the most important factor affecting the...
In this paper, performance of a physical layer network coding system consisting of two users and one relay with one transmit/receive antenna is analyzed in the presence of composite fading/shadowing effects modeled by generalized-K distribution. Amplify and forward method is used at the relay. The outage probability and symbol error rate of the system are analyzed based on the Padé approximation of...
Compressive Sensing (CS) is a very useful algorithm that is used in Ground Penetrating Radar (GPR) or through the wall imaging (TWI). CS generates high resolution images by decreasing the required measurement number. Although there are several recent studies about TWI with CS, they assume that targets are point like positioned at only discrete grid locations and wall thickness and its dielectric constant...
Via information extraction techniques, web pages are able to generate datasets for various studies such as natural language processing, and data mining. However, nowadays the uninformative sections like advertisement, menus, and links are in increase. The cleaning of web pages from uninformative sections, and extraction of informative content has become an important issue. In this study, we present...
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