Majlesi Journal of Telecommunication Devices
Volume:8 Issue: 2, Jun 2019

By expanding the use of digital images in various areas of everyday life, such as medicine, identification, satellite imagery, and even personal cameras and machine vision, it is felt more effective in applying quality improvements to the images used. The low-quality images in the machine's vision can expose the efficacy of later processing, such as feature extraction, classification, and pattern recognition. In this thesis, a new method for improving the quality of images based on the extraction of Godin’s combined feature and model has been proposed. Based on the fact that each homogeneous region in the image has a Gaussian distribution histogram, this distribution can be divided into smaller histograms. For the histogram division efficacy, the image is transmitted from the RGB space to the HSV space and the histogram division is applied to the severity region, and the histogram is applied to each sub Histogram based on the statistical characteristics, and the image. Improved results are returned to the RGB color space. Several qualitative and quantitative criteria have been used to evaluate the proposed method. Qualitative comparison results show improved image quality compared to histogram equivalence methods and linear contrast traction. Quantitative evaluation criteria, such as entropy and spatial frequency, as well as signal to noise ratio, and peak signal to noise ratio, are generally proposed for superiority of the method.

In most applications of intelligent networks equipped with wireless sensors, it is not possible to charge the nodes’ battery consistency and it is impossible under some conditions. Protocols designed for this type of networks should be energy efficient. The rapid consumption of battery power in wireless sensors and high power consumption in data transmission are two main challenges of this area. Nodes’ clustering is a natural way of categorizing nodes close together with the aim of using related data and removing plug-in data. However, existing clustering protocols are unbalanced in the term of energy consumption. The cluster heads are not distributed equally and overload clusters (with excess load) are much shorter than under-load clusters (low load). To solve this problem, an improved cuckoo search-based clustering algorithm (ICSCAS) has been proposed in present study. Also, performance evaluation of ICSCAS and its comparison with advanced clustering schemes in terms of total energy and residual energy consumption have been represented.

Manned and unmanned fast crafts, like unmanned aerial vehicle (UAV), are of interested weapon systems and will be paid attention in future offensive and defensive doctrine. This novel case, needs innovation in different areas like armament, navigation, communication and especially electronic warfare. Communication, radar and optical electronic warfare subsystems are necessary for increasing survivability and success in future missions. In this article wee perform future study of electronic warfare subsystems for fast crafts.

In this paper, the effects of the delay caused by the frequency change in self-priming locking oscillators are investigated in the phase lock loops. Self-injected locking phenomena in oscillators are used to reduce phase noise and more sustainability. Instead of using an external signal in an intruder lock, part of the output signal itself is returned to the oscillator again. In this case, the time required to restore the circuit after the injection of the external frequency is important, especially when this oscillator is used in the shape of a phase lock loop. This delay has the ability to unstable the phase lock loop. In this paper, the stability requirements for phase locking loops with delayed oscillators are fully investigated and the results are validated by simulation.

According to the importance of underwater exploration, the attention of many researchers has been attracted to underwater sensor networks (UWSNs). Problems of UWSNs are large propagation delay, low bandwidth, and limited energy. Because of these reasons, in this paper, we propose a new routing method in UWSNs that considers these factors and also achieves better load balancing in the network. In this method, relay nodes are used for routing. The relay nodes have a higher traffic load compared to the other nodes. They remove some burden from the overloaded nodes. The relay nodes shorten the transmission distance between source and destination. They have more energy compared to the other nodes. Our results show that the deployment of relay nodes in sensor networks helps to balance energy consumption and enhance the network lifetime. Nodes, after calculating the distance to the relay nodes and finding the nearest relay node, transmit packets to the nearest relay node for onetime immediately, so this method does not have holding time and it has less delay. The results are compared with DBR and CODBR. The results show that our method achieves more network lifetime, less delay and energy consumption compared to DBR and CODBR.

In irreducible subshifts, a word m is synchronizing if whenever vm and mw are admissible words, then vmw is admissible as well. A word m is (left) half (resp. weak) synchronizing, when there is a left transitive ray (resp. a left ray) x- such that if x-m and mw are admissible, then x-mw is also admissible. The respective subshifts are called half (resp. weak) synchronized. K. Thomsen in [On the structure of a sofc shift space, American Mathematical Society, 356, Number 9, p. 557-3619] considers a synchronized component of a general subshift and investigates the approximation of entropy from inside of this component by some certain SFT’s. We, using a rather different approach, show how this result extends to weak synchronized systems.