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29,061 Article Results

Miniaturization of Broadband Wilkinson Power Dividers

10.11591/ijeecs.v10.i1.pp241-247
Nadera Najib , Kok Yeow You , Chia Yew Lee , Mohamad Ngasri Dimon , Nor Hisham Khamis
This paper proposed three modified Wilkinson power dividers in order to achieve a size reduction and a wide bandwidth. The first structure presented the power divider using compact folded step impedance transmission lines rather than the uniform microstrip line design for operating center frequency of 3 GHz. The second structure showed the power divider with delta-stub for 2.4 GHz. Finally, the third modified structure introduced the two-section Wilkinson power divider using series-delta stub for center frequency of 2.4 GHz as well. The study managed to get an overall dimension of 15 mm × 9.5 mm for the first proposed design achieving a reduction of 75.6 % and fractional bandwidth of 133 %. For the second proposed structure, the size was 15 mm × 15 mm with a reduction of 56 % and fractional bandwidth of 56 %.  While the third design size was 17 mm × 15 mm with a reduction of 63.6 % and the structure achieved a broadband bandwidth with fractional bandwidth of 220 %.  The proposed power dividers used RT/duroid 5880 substrate with a thickness of 0.38 mm. Simulation and measurement results indicated that the modified power dividers showed equal power division, good phase balance, high isolation between output ports, and good return loss better than -12 dB covering the operating frequency range.
Volume: 10
Issue: 1
Page: 241-247
Publish at: 2018-04-01

Design of Negative Resistance Oscillator with Rocord Low Phase Noise

10.12928/telkomnika.v16i2.6999
Ayoub; University Complex Malki , Jamal; University Complex Zbitou , Larbi; University Complex El Abdellaoui , Mohamed; Microwave group ESEO Angers Latrach , Abdelali; University Complex Tajmouati , Ahmed; University Complex Errkik
The aim of this paper is to use a new design of a negative resistance microwave oscillator in order to fabricate oscillator with very good performance in terms of output power, efficiency, stability and phase noise. In this study the new concept of oscillator using distributed resonator and micro-strip circuit elements improve performances of our structure. A micro-strip microwave oscillator with low phase noise based on an NPN silicon planar epitaxial transistor has been designed, fabricated, and characterized. In this design, each step has been conducted by using Advanced Design System (ADS) and following a theoretical study which enable to optimize the different performances of the whole circuit. The oscillator produce a sinusoidal signal with spectrum power of 12.25 dBm at 2.45 GHz into 50 Ω load when polarized at Vcc=15V with DC to RF efficiency of 16. The obtained phase noise of -120 dBc/Hz at 100 Hz offset is the result of the use of high Q factor resonator and the depth study of the parameters of the oscillator. Simulation and measurement results are in good agreement.
Volume: 16
Issue: 2
Page: 586-593
Publish at: 2018-04-01

Power Efficient Clock Distribuition for Switched Capacitor DC-DC Converters

10.11591/ijeecs.v10.i1.pp27-36
A. S. R. Murthy , Sridhar T.
In various VLSI based digital systems, on-chip interconnects have become the system bottleneck in state-of-the-art chips, limiting the performance of high-speed clock distributions and data communication devices in terms of propagation delay and power consumption. Increasing power requirements and power distribution to multi-core architectures is also posing a challenge to power distribution networks in the integrated circuits. Clock distribution networks for the switched capacitor converters becomes a non-trivial task and the increased interconnect lengths cause clock degradation and power dissipation. Therefore, this paper introduce low swing signaling schemes to decrease delay and power consumption. A comparative study presented of low voltage signaling schemes in terms of delay, power consumption and power delay product. Here, we have presented a power efficient signaling topology for driving the clocks to higher interconnect lengths.
Volume: 10
Issue: 1
Page: 27-36
Publish at: 2018-04-01

Implementation of Controlled Robot for Fire Detection and Extinguish to Closed Areas Based on Arduino

10.12928/telkomnika.v16i2.8197
Ihsan A.; Al-Esra'a University Taha , Hamzah M.; Al-Esra'a University Marhoon
The wireless control systems are taking a special importance in the recent years, where the wireless control system provide several advantages; including the disposal of the using wire and periodic maintenance of data transmission wires, in the science of robot wireless control unit is the main part of the fire treatment and extinguish robot system. The lives of firefighters exposed to the risk of death and Rima, therefore the use of remote control systems more secure is necessary. In this, paper a fire-extinguish robot used for extinguishing the fire in general and in treatment fires in the closed areas for protecting employees in the field of fire suppression from combustion, exposure or inhalation to the toxic gases. The basic idea of fire detection and treatment robot based on detect the fire by the wireless camera and flame sensor then suppression the fire by send command from mobile phone through Bluetooth connection to make water pump turn "ON", and the fire then extinguished.
Volume: 16
Issue: 2
Page: 654-664
Publish at: 2018-04-01

Modified 128-EEA2 Algorithm by Using HISEC Lightweight Block Cipher Algorithm with Improving the Security and Cost Factors

10.11591/ijeecs.v10.i1.pp337-342
Alyaa Ghanim Sulaiman , Sufyan Salim Mahmood AlDabbagh
128-EEA2 (Evolved Packet System Encryption Algorithm 2) is a confidentiality algorithm which is used to encrypt and decrypt block of data based on confidentiality key. This confidentiality algorithm 128-EEA2 is based on the AES-128 which is the block cipher algorithm of 128 bit in CTR mode. In this paper, we are going to replace the AES-128 block cipher algorithm by HISEC block cipher algorithm for two reasons such as reducing cost and ameliorate security factor.
Volume: 10
Issue: 1
Page: 337-342
Publish at: 2018-04-01

Notice of Retraction Digital Image Steganography Using Bit Flipping

10.11591/ijict.v7i1.pp1-7
Aditya Kumar Sahu , Gandharba Swain
Notice of Retraction-----------------------------------------------------------------------After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IAES's Publication Principles.We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper.The presenting author of this paper has the option to appeal this decision by contacting info@iaesjournal.com.-----------------------------------------------------------------------This article proposes bit flipping method to conceal secret data in the original image. Here a section consists of 2 pixels and there by flipping one or two LSBs of the pixels to hide secret information in it. It exists in 2 variants. The variant-1 and variant-2 both use 7th and 8th bit to conceal the secret data. Variant-1 hides 3 bits per a pair of pixels and the variant-2 hides 4 bits per a pair of pixels. Our proposed method notably raises the capacity as well as bits per pixel that can be hidden in the image compared to existing bit flipping method. The image steganographic parameters such as, peak signal to noise ratio (PSNR), hiding capacity, and the quality index of the proposed techniques has been compared with the existing bit flipping technique
Volume: 7
Issue: 1
Page: 1-7
Publish at: 2018-04-01

Improved Routing Protocol in Mobile Ad Hoc Networks Using Fuzzy Logic

10.12928/telkomnika.v16i2.6426
Seyed Amin; Ferdowsi University of Mashhad Hosseini Seno , Ali Abdi; Ferdowsi University of Mashhad Seyedkolaei
In mobile ad hoc networks, route selection is one of the most important issues that is studied in these networks as a field of research. Many articles trying to provide solutions to choose the best path in which the important parameters such as power consumption, bandwidth and mobility are used. In this article, in order to improve the solutions presented in recent papers parameters such as power remaining, mobility, degree node and available bandwidth are used by taking the factors for each parameter in proportion to its influence in choosing the best path. Finally, we compare the proposed solution with the three protocols IAOMDV-F, AODVFART and FLM-AODV with the help of OPNET simulation program based on network throughput, routing discovery time, the average number of hops per route, network delay.
Volume: 16
Issue: 2
Page: 728-738
Publish at: 2018-04-01

A Hybrid Formulation between Differential Evolution and Simulated Annealing Algorithms for Optimal Reactive Power Dispatch

10.12928/telkomnika.v16i2.8434
Farida; University of August 20th Laouafi , Ahcene; University of August 20th Boukadoum , Salah; University of August 20th Leulmi
The aim of this paper is to solve the optimal reactive power dispatch (ORPD) problem. Metaheuristic algorithms have been extensively used to solve optimization problems in a reasonable time without requiring in-depth knowledge of the treated problem. The performance of a metaheuristic requires a compromise between exploitation and exploration of the search space. However, it is rarely to have the two characteristics in the same search method, where the current emergence of hybrid methods. This paper presents a hybrid formulation between two different metaheuristics: differential evolution (based on a population of solution) and simulated annealing (based on a unique solution) to solve ORPD. The first one is characterized with the high capacity of exploration, while the second has a good exploitation of the search space. For the control variables, a mixed representation (continuous/discrete), is proposed. The robustness of the method is tested on the IEEE 30 bus test system.
Volume: 16
Issue: 2
Page: 513-524
Publish at: 2018-04-01

Kalman Filter Algorithm for Mitigation of Power System Harmonics

10.11591/ijece.v8i2.pp771-779
K. Dhineshkumar , C. Subramani
The maiden application of a variant of Kalman Filter (KF) algorithms known as Local Ensemble Transform Kalman Filter (LET-KF) are used for mitigation and estimation power system harmonics are proposed in this paper. The proposed algorithm is applied for estimating the harmonic parameters of power signal containing harmonics, sub-harmonics and inter-harmonics in presence of random noise. The KF group of algorithms are tested and applied for both stationary as well as dynamic signal containing harmonics. The proposed LET-KF algorithm is compared with conventional KF based algorithms like KF, Ensemble Kalman Filter (En-KF) algorithms for harmonic estimation with the random noise values 0.001, 0.05 and 0.1. Among these three noises, 0.01 random noise results will give better than other two noises. Because the phase deviation and amplitude deviation less in 0.01 random noise. The proposed algorithm gives the better results to improve the efficiency and accuracy in terms of simplicity and computational features. Hence there are less multiplicative operations, which reduce the rounding errors. It is also less expensive as it reduces the requirement of storing large matrices, such as the Kalman gain matrix used in other KF based methods.
Volume: 8
Issue: 2
Page: 771-779
Publish at: 2018-04-01

Sizing and Cost Analysis of Self-Consumed Solar PV DC System Compared with AC System for Residential House

10.11591/ijeecs.v10.i1.pp10-18
T. M. N. T. Mansur , N. H. Baharudin , R. Ali
The use of solar photovoltaic (PV) system has grown significantly in Malaysia after Renewable Energy Act has been gazetted in 2011.The objective of this paper is to highlight the technical and economic analysis of solar PV DC system to generate enough energy for residential customer group that consumed 200 kWh per month so that they are less dependent on energy from the utility grid. The results are then compared to the solar PV AC system with similar load setup. The methodology involves gathering solar energy resource, configuring daily load demand, sizing PV array, battery bank and inverter and lastly simulation of the design system by using Homer software.  Based on Homer simulation, the solar PV AC system required slightly larger PV array sizes than the solar PV DC system to compensate losses due to the inverter efficiency which is not counted in DC system.Moreover, the solar PV AC system is almost 8.0% more expensive with 6% higher COE than the solar PV DC system due to the present of inverter.Lastly, both systems will benefit from reduction of energy consumed up to 2,434 kWh annually and to the environmental aspect, will avoid 1.7 tons of CO2 releases into the atmosphere.
Volume: 10
Issue: 1
Page: 10-18
Publish at: 2018-04-01

Control Synthesis for Marine Vessels in Case of Limited Disturbances

10.12928/telkomnika.v16i2.7180
Mikhail; St. Petersburg State University Smirnov , Maria A.; St. Petersburg State University Smirnova
In view of rapid development of computer technology digital systems of automatic control are installed on the modern marine vessels for performance of various manoeuvres at optimal trajectories taking into account features of the ship and active disturbances. In this connection, great number of problems that deal with construction of automatic control systems, such as minimizing the fulfillment time of the maneuver, searching for the optimal trajectory, the suppression of various types of exogenous disturbances like wind and rough sea, arises. In the work, the problem of suppression of exogenous disturbances acting on a marine vessel, about which we have no information except its boundedness, is considered. The problem of searching of the controller as a static state feedback is the basis of offered approach. The system MATLAB-Simulink is accepted as the basic tool of the computer support. An example of modeling control system for the carrier is presented.
Volume: 16
Issue: 2
Page: 648-653
Publish at: 2018-04-01

Alternative Grounding Method Using Coconut Shell Charcoal as Media of Mesh Electrodes

10.12928/telkomnika.v16i2.8700
Moch; Brawijaya University Dhofir , Rini Nur; Brawijaya University Hasanah , Hadi; Brawijaya University Suyono , Avrizal Riva; Brawijaya University Belan
The utilization of coconut charcoal as alternative media of grounding was investigated. The mesh-electrode was made of stainless steel of 8-mm diameter, whereas its lattice dimension was 50cmx50cm. Four variations of lattice number were considered, i.e. 1-, 2-, and 4-lattice structures. Dry and wet charcoal media were considered. Mesh location was fixed in the depth of 80cm under the ground, while the 10cm of medium thickness variation was chosen. The resistance obtained using 10-cm thickness of charcoal layer in a mesh consisting of 1-, 2-, and 4-lattices were 268, 131, and 78 ohms consecutively. The addition of layer up to 80-cm resulted in a resistance decrease of 48%, 33%, and 44%. Using wet charcoal, the 10-cm layer produced 26.5, 17.5, and 14.8 ohms of grounding resistance and a reduction of 25%, 10%, and 3.6% subsequently for 1-, 2-, and 4-lattice mesh structure if the layer thickness was 80 cm.
Volume: 16
Issue: 2
Page: 488-494
Publish at: 2018-04-01

On the Comparison of Line Spectral Frequencies and Mel-Frequency Cepstral Coefficients Using Feedforward Neural Network for Language Identification

10.11591/ijeecs.v10.i1.pp168-175
Teddy Surya Gunawan , Mira Kartiwi
Of the many audio features available, this paper focuses on the comparison of two most popular features, i.e. line spectral frequencies (LSF) and Mel-Frequency Cepstral Coefficients. We trained a feedforward neural network with various hidden layers and number of hidden nodes to identify five different languages, i.e. Arabic, Chinese, English, Korean, and Malay. LSF, MFCC, and combination of both features were extracted as the feature vectors. Systematic experiments have been conducted to find the optimum parameters, i.e. sampling frequency, frame size, model order, and structure of neural network. The recognition rate per frame was converted to recognition rate per audio file using majority voting. On average, the recognition rate for LSF, MFCC, and combination of both features are 96%, 92%, and 96%, respectively. Therefore, LSF is the most suitable features to be utilized for language identification using feedforward neural network classifier.
Volume: 10
Issue: 1
Page: 168-175
Publish at: 2018-04-01

Improved Key Frame Extraction using Discrete Wavelet Transform with Modified Threshold Factor

10.12928/telkomnika.v16i2.7692
Hussein Ali; University of Technology Aldelfy , Mahmood Hamza; University of Technology Al-Mufraji , Thamir; University of Technology R. Saeed
Video summarization used for a different application like video object recognition and classification. In video processing, numerous frames containing similar information, this leads to time consumption and slow processing speed and complexity. By using key frames reducing the amount of memory needed for video data processing and complexity greatly. In this paper key frame extraction of Arabic isolated word using discrete wavelet transform (DWT) with modified threshold factor is proposed with different bases. The results for different wavelet basis db, sym and coif show the best result for numbers of key frames at the threshold factor value (0.75).
Volume: 16
Issue: 2
Page: 567-572
Publish at: 2018-04-01

A Real Time Vein Detection System

10.11591/ijeecs.v10.i1.pp129-137
Kazi Istiaque Ahmed , Mohamed Hadi Habaebi , Md Rafiqul Islam
Blood veins detection process can be cumbersome for nurses and medical practioners when it comes to special overweight type of patients.This simple routine procedure can lead the process into an extreme calamity for these patients. In this paper, we emphasized on a process for the detection of the vein in real time using the consecrations of Matlab to prevent or at least reduce the number of inescapable calamity for patients during the infusion of a needle by phlebotomy or doctor in everyday lives. Hemoglobin of the blood tissues engrossed the Near Infrared (NIR) illuminated light and Night vision camera is used to capture the scene and enhance the vein pattern clearly using Contrast Limited Adaptive Histogram Equalization (CLAHE) method. This simple approach can successfully also lead to localizing bleeding spots, clots from stroke …etc among other things.
Volume: 10
Issue: 1
Page: 129-137
Publish at: 2018-04-01
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