Articles
9,199 Documents
A 2.45 GHz Semi-Flexible wearable antenna for industrial, scientific and medical band applications
S. M. Shah;
N. F. A. Kadir;
Z. Z. Abidin;
F. C. Seman;
S. A. Hamzah;
N. Katiran
Indonesian Journal of Electrical Engineering and Computer Science Vol 15, No 2: August 2019
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v15.i2.pp814-822
In this work, a compact size, wearable microstrip patch antenna is designed, simulated and fabricated for the Industrial, Scientific and Medical (ISM) band applications with the operating frequency at 2.45 GHz. A semi-flexible substrate material which is Rogers Duroid RO3003™ with a relative dielectric constant, ε_r of 3, loss tangent, tan δ of 0.010 and thickness, h of 1.52 mm has been proposed to ensure it can be worn on clothes. The antenna has a low-profile feature with 24 × 28 mm2 in dimension. Investigation of the antenna under bending condition on the approximate human arm size is also performed and analysed to ensure that the wearable antenna is applicable for on-body. The bending investigation shows that the initial resonant frequency of 2.45 GHz is shifted to 2.3 GHz. However, the reflection coefficient at 2.45 GHz is still greater than the -10-dB which implies that the antenna is still functional at that particular frequency. The Specific Absorption Rate (SAR) of the antenna has also been simulated to examine whether the antenna obeys the SAR limits under the FCC and CNIRP guidelines. The SAR values obtained show that the antenna obeys the standard for 1 mW input power. The SAR value for 1g of human tissue is computed at 0.03999 W/kg (FCC standard: 1.6 W/kg) while for 10g is at 0.01936W/kg (CNIRP standard: 2 W/kg).
Optimal Coordination of Overcurrent and Distance Relays Using Cuckoo Optimization Algorithm
Farhad Namdari;
Sajad Samadinasab;
Nader Shojaei;
Mohammad Bakhshipour
Indonesian Journal of Electrical Engineering and Computer Science Vol 16, No 3: December 2015
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v16.i3.pp389-400
The duty of protective systems is the timely detection of fault and removing it from the power network. The accuracy of the results and reducing the execution time of the optimizing algorithm are two crucial elements in selecting optimizing algorithms in protective functions. The most important protective elements that are used in power networks are distance and overcurrent relays. In this article, a new algorithm is presented to solve the optimization problem of coordination of overcurrent and distance relays by using Cuckoo Optimization Algorithm which considers the non-linear model overcurrent relays at all stages of setting. The proposed method is tested on a standard 8-bus power system network. Also the results obtained have been compared with other evolutionary algorithms. The results show that the proposed approach can be provide more effective and practical solutions to minimize the time function of the relays and achieving optimal coordination in comparison with previous studies on optimal coordination of overcurrent and distance relays in power system networks.
Multi-focus Image Fusion Based on Region Segmentation
Yuan Jia-zheng;
Li Qing;
Sun Bo-xuan
Indonesian Journal of Electrical Engineering and Computer Science Vol 11, No 11: November 2013
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
We proposed a new image fusion algorithm based on region segmentation. The algorithm divided the adjacent region from the image through the edge detection, then using wavelet transform with different high-frequency fusion method in each sub-region, to retain the edge information of the source image. The experimental results showed that the image fusion algorithm based on region segmentation can overcome the drawbacks of single segmentation rule and processing in specific part, and the effect is better than the traditional wavelet-based image fusion algorithm. DOI: http://dx.doi.org/10.11591/telkomnika.v11i11.3521
The Optimization of Finishing Train Based on Improved Genetic Algorithm
Hongxia Liu;
Xin Chen;
Rongyu Li
Indonesian Journal of Electrical Engineering and Computer Science Vol 12, No 5: May 2014
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
The central issue of finishing train is that we should distribute the thickness of each exit with reason and determine the rolling force and relative convexity. The optimization methods currently used are empirical distribution method and the load curve method, but they both have drawbacks. To solve those problems we established a mathematical model of the finishing train and introduced an improved Genetic Algorithm. In this algorithm we used real number encoding, selection operator of a roulette and elitist selection and then improved crossover and mutation operators. The results show that the model and algorithm is feasible and could ensure the optimal effect and convergence speed. The products meet the production requirements. DOI : http://dx.doi.org/10.11591/telkomnika.v12i5.3892
Online Performance Monitoring of Grid-Connected Photovoltaic System using Hybrid Improved Fast Evolutionary Programming and Artificial Neural Network
Puteri Nor Ashikin Megat Yunus;
Shahril Irwan Sulaiman;
Ahmad Maliki Omar
Indonesian Journal of Electrical Engineering and Computer Science Vol 8, No 2: November 2017
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v8.i2.pp399-406
This paper presents the development of online performance monitoring methods for grid-connected photovoltaic (GCPV) system based on hybrid Improved Fast Evolutionary Programming and Artificial Neural Network (IFEP-ANN). The approach has been developed and validated using previous predicted data measurement. Solar radiation (SR), module temperature (MT) and ambient temperature (AT) has been employed as the inputs, and AC output power (PAC) as the sole output to the neural network model. The actual data from the server has been called and uploaded every five minute interval into Matlab by using FTP (File Transfer Protocol) and the predicted AC output power has been produced based on the prediction developed in the training stages. It is then compared with the actual AC output power by using Average Test Ratio, AR. Any predicted AC output power less than the threshold set up, indicates an error has been occurred in the system. The obtained results show that the hybrid IFEP-ANN gives good performance by producing a sufficiently high correlation coefficient, R value of 0.9885. Besides, the proposed technique can analyse and monitor the system in online mode.
A simplify fuzzy logic controller design based safe experimentation dynamics for pantograph-catenary system
Mohd Faisal Farhan;
Nor Sakinah Abdul Shukor;
Mohd Ashraf Ahmad;
Mohd Helmi Suid;
Mohd Riduwan Ghazali;
Mohd Falfazli Mat Jusof
Indonesian Journal of Electrical Engineering and Computer Science Vol 14, No 2: May 2019
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v14.i2.pp903-911
Contact force between catenary and pantograph of high speed train is a crucial system to deliver power to the train. The inconsistence force between them can cause the contact wire oscillate a lot and it can damage the mechanical structure of system and produce electric arc that can reduce the performance of system. This project proposes a single-input fuzzy logic controller (SIFLC) to control the contact force between the pantograph-catenary by implement Safe Experimentation Dynamics (SED) method to tune the SIFLC parameters. The essential feature of SIFLC is that it is model-free type controller design with less pre-defined variables as compared to other existing model-based controllers. The performance of the SIFLC is analyzed in terms of input tracking of contact force of pantograph-catenary and time response specifications. A simplified model of three degree of freedom (3-DOF) pantograph-catenary system is considered. In this study, the simulation result shows that the SIFLC successfully track the given contact force with less overshoot with percentage different of peak to peak response from actual force 2% and fast response within 5.27s
Hydraulically operated palm oil loader system design as fresh fruit bunch collector
S. Sarip;
M. A. Suhot;
H. M. Kaidi;
M. F. Mohd Noor;
S. Abdul Aziz;
N. A. Bani;
M. S. Noorazizi
Indonesian Journal of Electrical Engineering and Computer Science Vol 17, No 1: January 2020
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v17.i1.pp228-236
Palm oil is one of the main agricultural contributors to Malaysia’s Gross Domestic Product (GDP). Although commercial palm oil plantations have flourished in Malaysia for decades, there is still room for improvement especially in minimizing manpower load and developing efficient machinery to improve the various processes involved in the palm oil industry from estate to the mills. This paper presents a modified towable backhoe to assist in the Fresh Fruit Bunch (FFB) collecting process as an effort to save time. The main objective of this study is to design a machine that can be used by smallholders of oil palm in order to help speed up the work process. With a boom extension and an innovative grabber, the pressure needed to operate the hydraulic system was analyzed to ensure the towable backhoe functioned effectively and fulfilled its objectives. From the calculations done, the maximum pressure that the system can supply is 31.28 MPa which is higher than the 11 MPa minimum required for the hydraulic system to operate.
Time-Weighted Uncertain Nearest Neighbor Collaborative Filtering Algorithm
Zhigao Zheng;
Jing Liu;
Ping Wang;
Shengli Sun
Indonesian Journal of Electrical Engineering and Computer Science Vol 12, No 8: August 2014
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.11591/ijeecs.v12.i8.pp6393-6402
To overcome the limitations of the traditional collaborative filtering recommendation algorithm, this paper proposed a Time-Weighted Uncertain Nearest Neighbor Collaborative Filtering Algorithm (TWUNCF). According to the actual application situation of recommendation system, the author weighted the product similarity and user similarity to ensure the data validity firstly, and then calculate the similarities of user and product and choose the trusted neighbor group as the recommended object adaptively based on the weight. Experimental results show that the algorithm can be used to improve data validity according to the time attribute, and balance the impact the different groups on the recommendation result, and avoid the problems which caused by the data sparseness. Theoretical analysis and experimental demonstrations show that the algorithm this paper proposed outperforms existing algorithms in recommendation quality, and improve the system's accuracy and recommendation efficiency.
Eliminating Noise of Mud Pressure Phase Shift Keying Signals with A Self-Adaptive Filter
Yue Shen;
Lingtan Zhang;
Heng Zhang;
Yinao Su;
Limin Sheng;
Lin Li
Indonesian Journal of Electrical Engineering and Computer Science Vol 11, No 6: June 2013
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
The feasibility of applying a self-adaptive filter to eliminate noise in the downhole mud pressure phase shift keying (PSK) signals is studied. The self-adaptive filter with carrier wave as the filter input signal and mud pressure PSK signal including noise as the filter expected input signal in structure was adopted to process the mud pressure PSK signals with the broadband signal characteristic in communication. Mathematical model of the filter was built to reconstruct the mud pressure PSK signals based on the evaluation criterion of least mean square error (LMS) and the mathematical model of mud pressure PSK signals. According to the filter mathematical model, a special self-adaptive control algorithm was adopted to realize the filter by adjusting the filter weight coefficients self-adaptively and the impacts of the filter step-size factor on signal to noise ratio (SNR) and distortion factors of the reconstructed mud pressure PSK signals were analyzed. Numerical calculation and simulation show that the self-adaptive filter can efficiently eliminate random noise in the signal frequency band and reconstruct the mud pressure PSK signals. In addition, low distortion factors of the reconstructed mud pressure PSK signals can be obtained by reasonable selecting the filter step-size factor. DOI: http://dx.doi.org/10.11591/telkomnika.v11i6.2610
Optimal Pricing Strategies and Computer Simulation of DCSC with Fairness Preference and Risk-Aversion Members
Guangxing Wei;
Qiang Lin
Indonesian Journal of Electrical Engineering and Computer Science Vol 11, No 12: December 2013
Publisher : Institute of Advanced Engineering and Science
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
Firstly, this paper develop a basic two-echelon DCSC model as the comparative benchmark in the general case of the stochastic demand effected by the service level of the retailer, where the manufacturer's optimal direct price, wholesale price and the retailer's optimal retail price were achieved under Stackelberg game. Then, through incorporate the fairness preference and risk-aversion characteristics into the basic DCSC model, the manufacturer's optimal direct price, wholesale price and the retailer's optimal retail price were obtained under Stackelberg game. At last, by the numerical simulation, the effect of fairness preference and risk aversion level on the optimal pricing strategies and utility of DCSC was examined respectively. The results show that for a DCSC with fairness preference and risk aversion members, the manufacturer and the retailer will choose a reduced price to avoid income risk even if the market demand is stable. Although the decision makers can realize the improvement of their own utility in some circumstances, the utility of the whole supply chain always presents decreasing. DOI: http://dx.doi.org/10.11591/telkomnika.v11i12.3686