Institute of Electron Technology
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Dynamically-adaptive Weight in Batch Back Propagation Algorithm via Dynamic Training Rate for Speedup and Accuracy Training, Journal of Telecommunications and Information Technology, 2017, nr 4
Get PDFThe main problem of batch back propagation (BBP) algorithm is slow training and there are several parameters need to be adjusted manually, such as learning rate. In addition, the BBP algorithm suffers from saturation training. The objective of this study is to improve the speed up training of the BBP algorithm and to remove the saturation training. The training rate is the most significant parameter for increasing the efficiency of the BBP. In this study, a new dynamic training rate is created to speed the training of the BBP algorithm. The dynamic batch back propagation (DBBPLR) algorithm is presented, which trains with adynamic training rate. This technique was implemented with a sigmoid function. Several data sets were used as benchmarks for testing the effects of the created dynamic training rate that we created. All the experiments were performed on Matlab. From the experimental results, the DBBPLR algorithm provides superior performance in terms of training, faster training with higher accuracy compared to the BBP algorithm and existing works
Availability Analysis of Different PON Models, Journal of Telecommunications and Information Technology, 2017, nr 4
Get PDFDue to the increasing demands of individual users, Passive Optical Networks (PON) are a promising technology for future broadband access networks. Reliable access to network services is a very important feature, so the availability of the connection is becoming one of the most important requirements. Failure of the optical fiber occurring between the Optical Line Terminal (OLT) and the passive optical splitter can cause the services becoming unavailable for a large number of users, so it is necessary to prevent such an occurrence by providing backup resources – in this case a spare optical fiber. When constructing the spare path (protection fiber), it is important to keep in mind that, if possible, the working and the spare fiber should not be positioned within the same cable. Failure of the optical fiber between the passive splitter and the individual user also means a loss of service for that user. In that case, protection may be offered by adding spare fibers. The question is, however, whether such a solution is cost-effective, as it would lead to a significant cost increase in the construction of the access network. This paper presents the availability analysis conducted for different PON models
The Alive-in-Range Medium Access Control Protocol to Optimize Queue Performance in Underwater Wireless Sensor Networks, Journal of Telecommunications and Information Technology, 2017, nr 4
Get PDFTime synchronization between sensor nodes to reduce the end-to-end delay for critical and real time data monitoring can be achieved by cautiously monitoring the mobility of the mobile sink node in underwater wireless sensor networks. The Alive-in-Range Medium Access Control (ARMAC) protocol monitors the delay of sensitive, critical and real-time data. The idea evolves as it involves reduction in duty cycle, precise time scheduling of active/sleep cycles of the sensors, monitoring the mobility of the sink node with the selection of appropriate queues and schedulers. The model for the path loss due to attenuation of electromagnetic wave propagation in the sea water is explained. The three-path reflection model evaluating reflection loss from the air-water and watersand interfaces as a function of distance between sensors and water depth is introduced. The algorithms for effective path determination and optimum throughput path determination are elaborated. The results verify that implementation of the Alive-in-Range MAC protocol has reduced the total number of packets dropped, the average queue length, the longest time in queue, the peak queue length and the average time in queue significantly, making it relevant for critical and real-time data monitoring
Influence of Chirped DBR Reflector on the Absorption Efficiency of Multi-nanolayer Photovoltaic Structures: Wavelength-scale Analysis by the Method of Single Expression, Journal of Telecommunications and Information Technology, 2017, nr 3
Get PDFAn electromagnetic wavelength-scale analysis of the optical characteristics of multi-nanolayer photovoltaic (PV) structures: without an antireflection coating, with an antireflection coating on the top of the structure, and with both the antireflection coating on the top and a broadband non-periodic (chirped) distributed Bragg reflector (DBR) on the bottom of the structure is performed. All the PV structures studied are based on a Si p-i-n type absorber supported by a metallic layer (Cu) and SiO2 substrate. The top-to-bottom electromagnetic analysis is performed numerically by the method of single expression (MSE). Absorbing and reflecting characteristics of the multi-nanolayer PV structures are obtained. The influence of the thicknesses and permittivities of the layers of the PV structures on the absorbing characteristics of the structures is analyzed to reveal favourable configurations for enhancement of their absorption efficiency. The localizations of the electric component of the optical field and the power flow distribution within all the PV structures considered are obtained to confirm an enhancement of the absorption efficiency in the favorable configuration. The results of the electromagnetic wavelength-scale analysis undertaken will have scientific and practical importance for optimizing the operation of thin-filmmulti-nanolayer PV structures incorporating a chirped DBR reflector with regards to enhancing their efficiency
Energy Efficient Scheduling Methods for Computational Grids and Clouds, Journal of Telecommunications and Information Technology, 2017, nr 1
Get PDFThis paper presents an overview of techniques developed to improve energy efficiency of grid and cloud computing. Power consumption models and energy usage proles are presented together with energy efficiency measuring methods. Modeling of computing dynamics is discussed from the viewpoint of system identication theory, indicating basic experiment design problems and challenges. Novel approaches to cluster and network-wide energy usage optimization are surveyed, including multi-level power and software control systems, energy-aware task scheduling, resource allocation algorithms and frameworks for backbone networks management. Software-development techniques and tools are also presented as a new promising way to reduce power consumption at the computing node level. Finally, energy-aware control mechanisms are presented. In addition, this paper introduces the example of batch scheduler based on ETC matrix approach
Development of Data Processing Tools for the Analysis of Radargrams in Utility Detection Using Ground Penetrating Radar, Journal of Telecommunications and Information Technology, 2017, nr 3
Get PDFThe extraction of quantitative information from Ground Penetrating Radar (GPR) data sets (radargrams) to detect and map underground utility pipelines is a challenging task. This study proposes several algorithms included in the main stages of a data processing chain associated with radargrams. It comprises preprocessing, hyperbola enhancing, hyperbola detection and localization, and parameter extraction. Additional parameters related to the GPR system such as the frequency band and the polarization bring data sets additional information that need to be exploited. Presently, the algorithms have been applied step by step on synthetic and experimental data. The results help to guide future developments in signal processing for quantitative parameter estimation
Quality Aspects in Digital Broadcasting and Webcasting Systems: Bitrate versus Loudness, Journal of Telecommunications and Information Technology, 2017, nr 2
Get PDFIn this paper the quality aspects of bitrate and loudness in digital broadcasting and webcasting systems are examined. The authors discuss a survey concerning user preferences related with processing and managing audio content. The coding efficiency of a popular audio format is analyzed in the context of storing media. An objective study on a representative group of signal samples, as well as a subjective study of the perceived quality of real-time broadcasted and webcasted radio programs are performed
The Microwave Sources for EPR Spectroscopy, Journal of Telecommunications and Information Technology, 2017, nr 2
Get PDFRapid development of many scientific and technical disciplines, especially in material science and material engineering increases a demand for quick, accurate and cheap techniques of materials investigations. The EPR spectroscopy meets these requirements and it is used in many fields of science including biology, chemistry and physics. For proper work, the EPR spectrometer needs a microwave source, which are reviewed in this paper. Vacuum tubes as well as semiconductor generators are presented such as magnetron, klystron, traveling wave tube, backward wave oscillator, orotron, gyrotron, Gunn and IMPATT diodes. In this paper main advantages of gyrotron usage, such as stability and an increased spectral resolution in application to EPR spectroscopy is discussed. The most promising and reliable microwave source is suggested
Sensor Hop-based Energy Efficient Networking Approach for Routing in Underwater Acoustic Communication, Journal of Telecommunications and Information Technology, 2017, nr 1
Get PDFnderwater Wireless Sensor Networks are deployed to explore the world under the water, measure different parameters and communicate the data to the surface, in the widespread applications. The main operating technology of these networks is the acoustic communication. The communication among the sensors and finally to the surface station requires a routing protocol. The sensors being battery limited and unfeasible to be replaced under the water requires an energy efficient routing protocol. Clustering imparted in routing is an energy saving technique in sensor networks. The routing may involve single or multi hop communication in the sensor networks. The paper gives a comparative study of the benchmark protocol multi-hop LEACH with the proposed Sensor Hop-based Energy Efficient Networking Approach (SHEENA) for the shallow as well as deep water in three dimensional Underwater Wireless Sensor Networks. The network energy model for the Underwater Wireless Sensor Networks is based among the different acoustic channel characteristics. The proposed approach is found to give better response