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27,404 Article Results

Research on Optimization Strategy to Data Clustered Storage of Consistent Hashing Algorithm

10.12928/telkomnika.v14i3.3550
Ningjia; Changchun University of Science and Technology Qiu , Xiaojuan; Jilin University Hu , Peng; Changchun University of Science and Technology Wang , Huamin; Changchun University of Science and Technology Yang
This paper has been withdrawed due to has major technical problems.---------------------------------------------------------------------This paper presents a consistent hashing data optimize multiple copy distributed clustered storage placement strategy, using technology to create a virtual node and aliquots storage area to ensure the balanced distribution of data storage. With the speed of data processing accelerated, it is possible for clusters actual required to complete the expansion, and complete the development of adaptive optimization. Experiments show that the execution speed has effectively improved to ensure the load balance. With possible extensions and reducing problems treatment in actual situation, oscillation has little impact on the load balancing, and the execution time is consistent with the proportion of the load trends.
Volume: 14
Issue: 3
Page: 824-830
Publish at: 2016-09-01

The Design and Performance Analysis of DTMB System

10.12928/telkomnika.v14i3.3830
Emy; Gunadarma University Haryatmi , Tubagus Maulana; Gunadarma University Kusuma , Busono; Gunadarma University Soerowirdjo , Purnawarman; Gunadarma University Musa
Various standard in digital television broadcasting system has been developed in the world, one of which is the Digital Terrestrial Multimedia Broadcasting, or abbreviated as DTMB that currently used by China and Hong Kong. DTMB has several standard configurations and parameters. In this research, DTMB system was designed and the results was validated through simulation using computer program, named Simulink. The parameters used in this research is the FEC with code rate of 0.4, 4QAM modulation, interleaver mode 1 and using a single carrier transmission mode. Stream format used in the simulation was MPEG2-TS as the input for DTMB system. Parameters selection was based on low implementation complexity, but with good results. Two important things in DTMB system is the existence of FEC and TDS-OFDM. FEC consists of cascaded BCH as the outer encoder/decoder (codec) and LDPC as the inner codec. The reason of using TDS-OFDM because it provides better picture quality when the receiver is in motion. The test results have shown that for static video, DTMB was able to receive video with identical quality compared to the original video, when the value of SNR=11dB and SNR=12dB for dynamic video. It is shown that after going through the process from LDPC to BCH, the number of bit errors decreased while the value of SNR increased.
Volume: 14
Issue: 3
Page: 873-879
Publish at: 2016-09-01

Error Resilient Multipath Video Delivery on Wireless Overlay Networks

10.12928/telkomnika.v14i3.3155
Uma; Amrita Vishwa Vidyapeetham, Amrita School of Engineering Bengaluru Campus Maheswari , Sudarshan; Amrita Vishwa Vidyapeetham, Amrita School of Engineering Bengaluru Campus TSB
Real time applications delivering multimedia data over wireless networks still pose many challenges due to high throughput and stringent delay requirements. Overlay networks with multipath transmission is the promising solution to address the above problems. But in wireless networks the maintenance of overlay networks induce additional overheads affecting the bulky and delay sensitive delivery of multimedia data. To minimize the overheads, this work introduces the Error Compensated Data Distribution Model (ECDD) that aids in reducing end to end delays and overheads arising from packet retransmissions. The ECDD adopts mTreebone algorithm to identify the unstable wireless nodes and construct overlay tree. The overlay tree is further split to support multipath transmissions. A sub packetization mechanism is adopted for multipath video data delivery in the ECDD. A forward error correction mechanism and sub-packet retransmission techniques adopted in ECDD enables to reduce the overhead and end to end delay. The simulation results presented in this paper prove that the ECDD model proposed achieves lower end to end delay and outperforms the existing models in place. Retransmission requests are minimized by about 52.27% and bit errors are reduced by about 23.93% than Sub-Packet based Multipath Load Distribution.
Volume: 14
Issue: 3
Page: 894-903
Publish at: 2016-09-01

Comparison of Five Level and Seven Level Inverter Based Static Compensator System

10.11591/ijeecs.v3.i3.pp706-713
G. Ramya , V. Ganapathy
The STATCOM is one of the shunt type FACTS controllers which can supply reactive power and improve bus voltage. STATCOM has advantages like transient free switching and smooth variation of reactive power. This paper deals with the comparison of five level and seven level based STATCOM systems. Usually DC output from the PV source is amplified using a single boost converter. The output of the boost converter is applied to the multilevel inverter system. The ability of STATCOM to improve the receiving end voltage is analyzed using the proposed boost converter. The performance of five level and seven level STATCOM systems are compared in terms of THD and receiving end voltage
Volume: 3
Issue: 3
Page: 706-713
Publish at: 2016-09-01

Characterization of Erbium Doped Photonic Crystal Fiber

10.12928/telkomnika.v14i3.3655
Farah Diana; Universiti Teknologi Malaysia Mahad , Abu Sahmah; Universiti Teknologi Malaysia M.Supa'at , David Ian; Universiti Teknologi Malaysia Forsyth , Tong; City University London Sun , Asrul Izam; Universiti Teknologi Malaysia Azmi
Photonic crystal fibers (PCFs) which exhibit unique and tremendous optical properties have been undergoing quick growth in recent years. Studies on the characteristics of various types of PCFs have been reported. However, characterization on erbium-doped PCF has not previously been investigated. Therefore, in this paper, an erbium-doped core PCF having 7 rings of hexagonal air holes has been modeled. A perfectly matched layer (PML) is modeled within the PCF structure and simulated using Finite Element Method (FEM) using COMSOL software. The PML is optimized by varying the radius and thickness of the layer. Modal properties of the PCF have been investigated in terms of its effective index of the supported fundamental mode, confinement loss and thickness of the perfectly matched layer. This erbium-doped PCF has a confinement loss of 1.0E-6 at 1500 nm and a maximum effective refractive index of 1.476. This paper gathers useful data, which could be used for studying the characteristics of a PCF.
Volume: 14
Issue: 3
Page: 880-886
Publish at: 2016-09-01

Internet Protocol Based Satellite On-Board System

10.12928/telkomnika.v14i3.3512
Emir; Institut Teknologi Bandung Husni , Nazmi; Institut Teknologi Bandung Febrian , Angga; Institut Teknologi Bandung Putra
The reliability of satellite data communication can be enhanced by designing two subsystems involving data communication among subsystem and data communication between satellie and Ground Station (GS). In this paper, Error Control Coding (ECC) is applied in satellite data communication with Automatic Repeat Request (ARQ) method. Further, bit error checking uses the calculation of 15 bit Cyclic Redundancy Check (CRC) Controller Area Network (CAN) standard. The calculation of CRC is attached in CAN frame over IP communication protocol between primary OBC and secondary OBC. OBC is designed by implementing Triple Modular Redundant system on a Linux-based operating system. The CAN frame over IP simulation with manual input is found to correct all corrupted data. When the simulation uses NetEM, the system corrects 100 % data with 0-10 % value of corruption with maximum time transfer of 84.472 seconds. ION DTN is also found to correct all corrupted data with values from 0 to 2 % and maximum delay at an altitude of 50,000 kilometer orbit using NetEm for TMTC mission. The testing results show that the system will keep carrying out its mission as long as a fault does not occur on all three OBC at the same time.
Volume: 14
Issue: 3
Page: 846-855
Publish at: 2016-09-01

An Improved Adaptive Niche Differential Evolution Algorithm

10.12928/telkomnika.v14i3.3591
Hui; Zhenjiang College Wang , Changtong; Zhenjiang College Song
Differential evolution (DE) algorithm is a random search algorithm by referring to the natural genetic and natural selection mechanism of the biological world and it is used to process the complicated non-linear problems which are difficult to be solved by traditional computational methods. However, subject to its own mechanism and single structure, the basic DE algorithm is easy to get trapped into local optimum and it is difficult to handle high-dimensional and complicated optimization problems. In order to enhance the search performance of the DE algorithm, this paper uses the idea of niche, decomposes the entire population into several niches according to the fitness, perform population selection by integrating the optimum reservation strategy to realize the optimal selection of niche, adjusts the fitness of the individual of the population, designs the adaptive crossover and mutation operators to make the crossover and mutation probabilities change with the individual fitness and enhances the ability of DE algorithm to jump out of the local optimal solution. The experiment result of benchmark function shows that the method of this paper can maintain solution diversity, effectively avoid premature convergence and enhance the global search ability of DE algorithm.
Volume: 14
Issue: 3
Page: 1035-1041
Publish at: 2016-09-01

Data Selection and Fuzzy-Rules Generation for Short-Term Load Forecasting Using ANFIS

10.12928/telkomnika.v14i3.3413
Mamunu; Faculty of Electrical Engineering, Universiti Teknologi Malaysia Mustapha , Mohd Wazir; Faculty of Electrical Engineering, Universiti Teknologi Malaysia Mustafa , Saiful Nizam; Faculty of Electrical Engineering, Universiti Teknologi Malaysia Abd. Khalid
Forecasting accuracy depends on data identification and model parameters. Volume of data and good analysis are the key factors that influence the accuracy of forecasting algorithm. This paper focused on data analysis with aim of determining the actual variables that affect the load consumption. Correlation analysis was used to determine how the load consumption is related to the forecasting variables (model inputs), and hypothesis test to justify the correlation coefficient of each variable. This produced tree different scenarios which ware used to forecast the load within short-term time frame. On the other hand, subtractive clustering and Fuzzy c-means (FCM) algorithms ware compared in fuzzy rules generation using Adaptive Neuro-Fuzzy Inference System (ANFIS) model, for short term electric load forecasting. Forecasting using Hypothesis test data with Subtractive clustering algorithm gave better accuracy compared to the other two approaches. But FCM algorithm is faster in all the three approaches. In conclusion, hypothesis test on the correlation coefficient of the data is a commendable practice for data selection and analysis in short-term load forecasting. Also, subtractive clustering algorithm is good in generating appropriate number of fuzzy rules, and the number depends on the number of input variables. Fuzzy c-means algorithm reduces the number of the rules irrespective of the number of input variables. 
Volume: 14
Issue: 3
Page: 791-799
Publish at: 2016-09-01

A Comprehensive Test Approach on High-Power Low-Noise Intermodulation Distortion

10.12928/telkomnika.v14i3.3715
Lei; Key Laboratory of Special Fiber Optics and Optical Access Networks, Ministry of Education Wang , Jingyi; Key Laboratory of Special Fiber Optics and Optical Access Networks, Ministry of Education Zhang
With the shortage of wireless communication bandwidth resource, the radio interferences occur so frequently. Currently, effcient frequency allocation algorithm designing and Intermoduation Distortion (IMD) suppression are two means to rationally improve the bandwidth resource. Therefore, four comprehensive approaches named stimulus isolation, channel crosstalk isolation; spectrum slight offset and Auto Level Control (ALC) leak control are proposed respectively to avoid the restriction of the periphery system’s noise and dynamic range of measurement instruments. Moreover, the high power and low noise detection approach, the auxiliary components amelioration and the measurement system improvement are analyzed. Finally, utilizing Silicon-On-Insulator (SOI) Radio Frequency (RF) switch as the carrier to do the experiment based on Advantest 93K tester. Experiment results show that the comprehensive optimized approaches can keep the whole system to less than -150 dBm (nearly 170 dBc) low noise range under the large signal cases. The actual intermodulation distortion signal could be rejected and sampled in precise accuracy which is nearly 20% improved. What’s more, the approaches are also beneficial to the expansion of the industrial multi-site test.
Volume: 14
Issue: 3
Page: 831-838
Publish at: 2016-09-01

Noisy Signal Processing Research based on Compressed Sensing Technology

10.11591/ijeecs.v3.i3.pp489-495
Guojun Qin , jingfang wang
Compressed sensing (CS) is a kind of sampling method based on signal sparse property, it can effectively extract the signal which was contained in the message. In this study, a new noise speech enhancement method was proposed based on CS process.  Voice sparsity is used to this algorithm in the discrete fast Fourier transform (Fast Fourier transform, FFT),and observation matrix is  designed in complex domain,  and the noisy speech compression measurement and de-noising are made by soft threshold,  and the speech signal is sparsely reconstructed and restored by separable approximation (Sparse Reconstruction by Separable Approximation, SpaRSA) algorithm, speech enhancementis improved.  Experimental results show that the denoising compression reconstruction is made for the noisy signal in  the algorithm, SNR margin is improved greatly, and the background noise can be more effectively suppressed .
Volume: 3
Issue: 3
Page: 489-495
Publish at: 2016-09-01

A Technique to Improve Ridge Flows of Fingerprint Orientation Fields Estimation

10.12928/telkomnika.v14i3.3112
Saparudin; Sriwijaya University Saparudin , Ghazali; Universiti Teknologi Malaysia Sulong
This paper is under in-depth investigation due to suspicion of possible plagiarism on a high similarity indexAn accurate estimated fingerprint orientation fields is a significant step for detection of singular points. Gradient-based methods are frequently used for estimating orientation fields but those methods are sensitive to noise. Fingerprints that perfect quality are seldom. They may be corrupted and degraded due to impression conditions or variations on skin. Enhancement of ridge flows improved the structure of orientation fields and hence increased the number of true singular points thereby conducting the overall performance of the classification process. In this paper, we provided discussion on the technique and implementation to improve local ridge flows segmentation; secondly, identification of noise areas and marking; thirdly, estimation of fingerprint orientation fields using gradient-based method and finally, enhancement of ridge flows using minimum variance of the cross centre block direction in squared gradients. A standard fingerprint database is used for testing of proposed technique to verify the tier of effectivity of algorithm. The experimental results suggest that our enhanced algorithm achieves visibly better ridge flows compare to other methods.
Volume: 14
Issue: 3
Page: 987-998
Publish at: 2016-09-01

Building Segmentation of Satellite Image based on Area and Perimeter using Region Growing

10.11591/ijeecs.v3.i3.pp579-585
Ervin Yohannes , Fitri Utaminingrum
A building can be known by look shape, color, and texture. Building can be detected by using many method. Region growing is one simple segmentation method because only use seed point. Before segmentation, the image must be preprocessing include sharpening, binerization by otsu method. Sharpening for clarify image and otsu method changed image valued 0 and 1. Next step is post-preprocessing include segmentation using region growing and opening closing operation. And the last process is detection building where building of detection will be signed. In this research, we present region growing for building segmentation by using both area and perimeter as a important variable in the region growing. Value of area more than 10 and perimeter is more than 50 are produced most of building.
Volume: 3
Issue: 3
Page: 579-585
Publish at: 2016-09-01

Temperature Control of the 25kW Parabolic Dish-Stirling Engine System

10.12928/telkomnika.v14i3.4055
Liaw Geok; Universiti Teknikal Malaysia Melaka Pheng , Mohd Ruddin; Universiti Teknikal Malaysia Melaka Ab Ghani , Chin; Universiti Teknikal Malaysia Melaka Kim Gan , Tole; Universitas Ahmad Dahlan Sutikno
This paper is under in-depth investigation due to suspicion of possible plagiarism on a high similarity indexNowadays, even though many researchers continue to investigate and study about Parabolic Dish based on Concentration Solar Power (CSP), the findings are not conclusive and do not provide accurate evidence and proof on the potential of CSP development in Malaysia. The missing link in the Parabolic Dish (PD) Stirling Engine system modelled is the control systems, which vary the amount of working gas in the Stirling engine. The temperature of the heater in PD system which has been modelled is overheated and causes damage to the heater material, low output efficiency, high thermal losses and effect to the lifespan of the PD system. Therefore, the primary aim of this paper was to design a control system to maximize output efficiency during a normal operation by maintaining the heater/absorber temperature at the highest safe operating point and preventing excessive range of threshold to prevent damage to the heater material.
Volume: 14
Issue: 3
Page: 800-806
Publish at: 2016-09-01

Distributed Clustering Based on Node Density and Distance in Wireless Sensor Networks

10.12928/telkomnika.v14i3.2712
Sasikumar; VIT University P , Shankar; VIT University T , Sibaram; VIT University Khara
Wireless Sensor Networks (WSNs) are special type of network with sensing and monitoring the physical parameters with the property of autonomous in nature. To implement this autonomy and network management the common method used is hierarchical clustering. Hierarchical clustering helps for ease access to data collection and forwarding the same to the base station. The proposed Distributed Self-organizing Load Balancing Clustering Algorithm (DSLBCA) for WSNs designed considering the parameters of neighbor distance, residual energy, and node density.  The validity of the DSLBCA has been shown by comparing the network lifetime and energy dissipation with Low Energy Adaptive Clustering Hierarchy (LEACH), and Hybrid Energy Efficient Distributed Clustering (HEED). The proposed algorithm shows improved result in enhancing the life time of the network in both stationary and mobile environment.
Volume: 14
Issue: 3
Page: 916-922
Publish at: 2016-09-01

Transformer Fault Diagnosis Method Based on Dynamic Weighted Combination Model

10.12928/telkomnika.v14i3.3545
Hongli; North China University of Water Resources and Electric Power Yun , Run; North China University of Water Resources and Electric Power Liu , Linjian; North China University of Water Resources and Electric Power Shangguan
The paper tried to integrate the DGA data with the gas production rate, which are the major indexes of transformer fault diagnosis. Duval’s triangle method, BP neural network and IEC three-ratio method were weighted. Firstly, the paper regarded the gas production rate as the independent variables, fitted the cubic curves of the gas production rate and variance of each diagnosis method, and then defined the weights of each algorithm through the data processing method of unequal precision. At last, the dynamic weighted combination diagnosis model was established. That is, the weight is different as the gas production rate changes although the method is identical. The results of diagnosis examples show that the accuracy rate of the weighted combination model is higher than any single algorithm, and it has certain stability as well.
Volume: 14
Issue: 3
Page: 815-823
Publish at: 2016-09-01
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