TELKOMNIKA (Telecommunication Computing Electronics and Control)
Submitted papers are evaluated by anonymous referees by single blind peer review for contribution, originality, relevance, and presentation. The Editor shall inform you of the results of the review as soon as possible, hopefully in 10 weeks. Please notice that because of the great number of submissions that TELKOMNIKA has received during the last few months the duration of the review process can be up to 14 weeks. Communication Engineering, Computer Network and System Engineering, Computer Science and Information System, Machine Learning, AI and Soft Computing, Signal, Image and Video Processing, Electronics Engineering, Electrical Power Engineering, Power Electronics and Drives, Instrumentation and Control Engineering, Internet of Things (IoT)
Articles
2,614 Documents
Circularly Polarized Proximity-Fed Microstrip Array Antenna for Micro Satellite
Muhammad Darsono;
Endra Wijaya
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 11, No 4: December 2013
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v11i4.1204
Design of circular polarization microstrip antenna array was developed to support micro-satellite technology. Circular polarization antenna array used for data transmission applications operating in the S band frequencies from the satellite to the ground station. In this study of the patch array using proximity coupling techniques in this study to obtain high gain and wide of bandwidth. The structure of the antenna array design consists of four identical square patch elements and to use the concept of corporate transmission line fed power divider network uses three transformers quarter-lambda T-junction. Bandwidth impedance matching for resonance between two patches is ¾ l antenna system for center frequency of 2.25 GHz. The antenna is designed using the method of moments through simulation with microwave office software applications. The results of simulations and measurements obtained antenna parameters, such as: bandwidth of return loss <-10 dB above 100 MHz resonant frequency shifted to 1.75%, VSWR (1 to 2), the bandwidth of axial ratio <3 dB is 1.6% (narrowband) and the maximum directivity (gain) is 9.128 dB. Overall study results showed good performance antenna array with circular polarization properties, high gain and operates in the S band frequency micro satellite system.
Numerical Calculation of Transient Thermal Characteristics in Gas-Insulated Transmission Lines
Li Hongtao Li Hongtao;
Shu Naiqiu;
Li Ling Li Ling;
Wu Xiaowen Wu Xiaowen
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 11, No 3: September 2013
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v11i3.945
For further knowledge of the thermal characteristics in gas-insulated transmission lines (GILs) installed above ground, a finite-element model of coupling fluid field and thermal field is established, in which the corresponding assumptions and boundary conditions are given. Transient temperature rise processes of the GIL under the conditions of variable ambient temperature, wind velocity and solar radiation are respectively investigated. Equivalent of surface convective heat transfer coefficient and heat flux boundary conditions are updated in the analysis process. Unlike the traditional finite element method (FEM), the variability of the thermal properties with temperature is considered. The calculation results are validated by the tests results reported in the literature. The conclusion provides method and theory basis for the knowledge of transient temperature rise characteristics of GILs in open environment.
A Simple Instrumentation System for Large Structure Vibration Monitoring
Didik R. Santoso
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 8, No 3: December 2010
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v8i3.628
A conventional instrumentation systems in monitoring vibration of large-scale infrastructure building such as bridges, railway, and others structural building, generally has a complex design. Makes it simple would be very useful both in terms of low-cost and easy maintenance. To make system become simple, low cost, and easy in maintenance, this paper proposes a distributed network for implementation system. The system consists of field bus topology, using single-master multi-slave architecture. Master is a control unit, built based on a PC equipped with RS-485 interface. Slave is a sensing unit; each slave is built by integrating a 3-axis vibration sensor within a microcontroller based data acquisition system. Vibration sensor is designed using the main components of a MEMS accelerometer. The software is developed for two functions; a control system hardware and a data processing. To verify performance of the developed instrumentation system, several laboratory tests have been performed. The result shows that the system has good performance.
Fault Diagnosis of Power Network Based on GIS Platform and Bayesian Networks
Yunfang Xie;
Yuhong Zhou;
Weina Liu
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 14, No 2: June 2016
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v14i2.2750
In order to determine the location of the fault components of the power network quickly and give troubleshooting solutions, this paper obtains a simplify structure of relay protection and circuit-breaker as key equipment by analyzing the power network topology of GIS platform and uses the Bayesian networks fault diagnosis algorithm and finally designs the power network fault diagnosis module based on GIS platform. Fault diagnosis algorithm based on Bayesian networks is a new method for power network fault diagnosis which deals with the power network fault diagnosis with incomplete alarm signals caused by the protection device’s and the circuit breaker’s malfunction or refusal to move, device failure of communication and other reasons in the use of Bayesian networks method. This method establishes the transmission line fault diagnosis model by using Noisy-Or, Noisy-And node model and similar BP neural network back propagation algorithm, and obtains the fault trust degree of each component by using the formula, and finally determines the fault according to the fault trust degree. The practical engineering application shows that the search speed and accuracy of fault diagnosis are improved by applying the fault diagnosis module based on GIS platform and Bayesian network.
Thermal Performance Analysis for Optimal Passive Cooling Heat Sink Design
Nur Warissyahidah Badrul Hisham;
Fatimah Sham Ismail;
Muhammad Azmi Ahmed Nawawi
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 15, No 2: June 2017
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v15i2.6140
Recent advances in semiconductor technology show the improvement of fabrication on electronics appliances in terms of performance, power density and even the size. This great achievement however led to some major problems on thermal and heat distribution of the electronic devices. This thermal problem could reduce the efficiency and reliability of the electronic devices. In order to minimize this thermal problem, an optimal cooling techniques need to be applied during the operation. There are various cooling techniques have been used and one of them is passive pin fin heat sink approach. This paper focuses on inline pin fin heat sink, which use copper material with different shapes of pin fin and a constant 5.5W heat sources. The simulation model has been formulated using COMSOL Multiphysics software to stimulate the pin fin design, study the thermal distribution and the maximum heat profile.
Design and Analysis of a Broadcast Network Using Logical Segmentation
Anyasi Francis;
Uzairue Stanley;
Enehizena O.N.;
Victor Matthews Olu;
Amaize Peter;
Nsikan Nkordeh
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 16, No 2: April 2018
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v16i2.8461
This study shows how the network performance of a flat switch network in the main library complex of Ambrose Ali University (AAU), Ekpoma can greatly be improved by logical segmentation. A survey of the flat switch network of the library complex was carried out to ascertain the physical and logical topology of the network and the number of hosts and network devices available. The kind of traffic transmitted over the network was also considered. Riverbed Modeler Academic Edition was used to simulate two replicas of the library network. One of the simulated networks was logically segmented by implementing Virtual Local Area Network (VLAN). Statistics like traffic dropped, traffic forwarded, traffic received, broadcast traffic dropped and traffic sent in bits/sec or packets/sec were collected from both simulations and the results were analyzed and compared. The results from the simulations showed that the application of VLAN immensely enhanced the network performance by about 75%(depending on the size of the network) because the logical segmentation increased the number of broadcast domain while reducing each of the broadcast size. This further implied that poor network design and large broadcast domain in a network, gravely affect the performance of a network.
Image Analysis using Color Co-occurrence Matrix Textural Features for Predicting Nitrogen Content in Spinach
Yusuf Hendrawan;
Indah Mustika Sakti;
Yusuf Wibisono;
Muchnuria Rachmawati;
Sandra Malin Sutan
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 16, No 6: December 2018
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v16i6.10326
This study aimed to determine the nitrogen content of spinach leaves by using computer imaging technology. The application of Color Co-occurrence Matrix (CCM) texture analysis was used to recognize the pattern of nitrogen content in spinach leaves. The texture analysis consisted of 40 CCM textural features constructed from RGB and grey colors. From the 40 textural features, the best features-subset was selected by using features selection method. Features selection method can increase the accuracy of image analysis using ANN model to predict nitrogen content of spinach leaves. The combination of ANN with Ant Colony Optimization resulted in the most optimal modelling with mean square error validation value of 0.0000083 and the R2 testing-set data = 0.99 by using 10 CCM textural features as the input of ANN. The computer vision method using ANN model which has been developed can be used as non-invasive sensing device to predict nitrogen content of spinach and for guiding farmers in the accurate application of their nitrogen fertilization strategies using low cost computer imaging technology.
Enhance interval width of crime forecasting with ARIMA model-fuzzy alpha cut
Yaya Sudarya Triana;
Astari Retnowardhani
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 3: June 2019
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v17i3.12233
With qualified data or information a better decision can be made. The interval width of forecasting is one of data values to assist in the selection decision making process in regards to crime prevention. However, in time series forecasting, especially the use of ARIMA model, the amount of historical data available can affect forecasting result including interval width forecasting value. This study proposes a combination technique, in order to get get a better interval width crime forecasting value. The propose combination technique between ARIMA model and Fuzzy Alpha Cut are presented. The use of variation alpha values are used, they are 0.3, 0.5, and 0.7. The experimental results have shown the use of ARIMA-FAC with alpha=0.5 is appropriate. The overall results obtained have shown the interval width crime forecasting with ARIMA-FAC is better than interval width crime forecasting with 95% CI ARIMA model.
Novel high functionality fault tolerant ALU
Shaveta Thakral;
Dipali Bansal
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 18, No 1: February 2020
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v18i1.12645
Miniaturization, cost, functionality, complexity and power dissipation are important and necessary design traits which need attention in circuit designing. There is a trade off between miniaturization and power dissipation. Smart technology is always searching for new paradigms to continue improve power dissipation. Reversible logic is one of smart computing deployed to avoid power dissipation. Researchers have proposed many reversible logic-based arithmetic and logic units (ALU). However, the research in the area of fault tolerant ALU is still under progress. The aim of this paper is to bridge the knowledge gap for a new researcher in area of fault tolerance using parity preserving logic gates rather than searching huge data through various sources. This paper also presents a high functionality based novel fault tolerant arithmetic and logic unit architecture. A comparison on optimization aspects is presented in tabular form and results shows that proposed ALU architecture is optimum balance in terms of all aspects of reversible logic synthesis. The proposed ALU architecture is coded in Verilog HDL and simulated using Xilinx ISE design suit 14.2 tool. The quantum cost of all gates used in proposed architecture is verified using RCViewer + tool.
Arabic digits speech recognition and speaker identification in noisy environment using a hybrid model of VQ and GMM
Abdelkbir Ouisaadane;
Said Safi;
Miloud Frikel
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 18, No 4: August 2020
Publisher : Universitas Ahmad Dahlan
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12928/telkomnika.v18i4.14215
This paper presents an automatic speaker identification and speech recognition for Arabic digits in noisy environment. In this work, the proposed system is able to identify the speaker after saving his voice in the database and adding noise. The mel frequency cepstral coefficients (MFCC) is the best approach used in building a program in the Matlab platform; also, the quantization is used for generating the codebooks. The Gaussian mixture modelling (GMM) algorithms are used to generate template, feature-matching purpose. In this paper, we have proposed a system based on MFCC-GMM and MFCC-VQ Approaches on the one hand and by using the Hybrid Approach MFCC-VQ-GMM on the other hand for speaker modeling. The White Gaussian noise is added to the clean speech at several signal-to-noise ratio (SNR) levels to test the system in a noisy environment. The proposed system gives good results in recognition rate.