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29,758 Article Results

Reliability Level List Based Iterative SISO Decoding Algorithm for Block Turbo Codes

10.12928/telkomnika.v16i5.7463
V; Amrita University Sudharsan , V; Amrita University Vijay Karthik , B; Amrita University Yamuna
An iterative Reliability Level List (RLL) based soft-input soft-output (SISO) decoding algorithm has been proposed for Block Turbo Codes (BTCs). The algorithm ingeniously adapts the RLL based decoding algorithm for the constituent block codes, which is a soft-input hard-output algorithm. The extrinsic information is calculated using the reliability of these hard-output decisions and is passed as soft-input to the iterative turbo decoding process. RLL based decoding of constituent codes estimate the optimal transmitted codeword through a directed minimal search. The proposed RLL based decoder for the constituent code replaces the Chase-2 based constituent decoder in the conventional SISO scheme. Simulation results show that the proposed algorithm has a clear advantage of performance improvement over conventional Chase-2 based SISO decoding scheme with reduced decoding latency at lower noise levels.
Volume: 16
Issue: 5
Page: 2040-2047
Publish at: 2018-10-01

A Review on ESCO’s Challenges and Project Management as a Solving Tool

10.11591/ijeecs.v12.i1.pp269-274
Waqar Tariq , Mohammad Lutfi Othman , Noor Izzri Abdul Wahab , Mansoor Ebrahim
The Energy Service Industry is now declared as a new source of growth for Malaysian Economy, many key players like MAESCO, Suruhanjaya Tenaga Energy Commission, KeTTHA and relevant ministries are working very hard on energy saving respective researches. There is a room for much more improvement in order to apply energy saving projects according to Malaysian environment .So far the application of project management principles are very rare in energy saving projects or in Malaysia termed as ESCO (Energy Service Company). This gives a way to synchronise project management techniques with respective implementations of energy saving projects focusing Malaysian infrastructure. In this article a review is conducted on new ways, techniques and procedures of project management and its synchronization with engineering needs especially electrical power conservation and saving projects. Moreover, the proposed research will also indicate the advancement or replacement of present system along with some advantages over our old system. A complete review is done on the background of ESCO its importance in energy saving also the relevancy of project manajement along with its basic princlples is discussed as to provide a solution for ESCO to comeover the chellenges in South East Asia generaly and in Malaysia specifically
Volume: 12
Issue: 1
Page: 269-274
Publish at: 2018-10-01

Optimizing Effort Parameter of COCOMO II Using Particle Swarm Optimization Method

10.12928/telkomnika.v16i5.9703
Kholed; Fatoni University Langsari , Riyanarto; Institut Teknologi Sepuluh Nopember (ITS) Sarno , Sholiq; Institut Teknologi Sepuluh Nopember Sholiq
Estimating the effort and cost of software is an important activity for software project managers. A poor estimate (overestimates or underestimates) will result in poor software project management. To handle this problem, many researchers have proposed various models for estimating software cost. Constructive Cost Model II (COCOMO II) is one of the best known and widely used models for estimating software costs. To estimate the cost of a software project, the COCOMO II model uses software size, cost drivers, scale factors as inputs. However, this model is still lacking in terms of accuracy. To improve the accuracy of COCOMO II model, this study examines the effect of the cost factor and scale factor in improving the accuracy of effort estimation. In this study, we initialized using Particle Swarm Optimization (PSO) to optimize the parameters in a model of COCOMO II. The method proposed is implemented using the Turkish Software Industry dataset which has 12 data items. The method can handle improper and uncertain inputs efficiently, as well as improves the reliability of software effort. The experiment results by MMRE were 34.1939%, indicating better high accuracy and significantly minimizing error 698.9461% and 104.876%.
Volume: 16
Issue: 5
Page: 2208-2216
Publish at: 2018-10-01

A Compact Wideband Monopole Antenna using Single Open Loop Resonator for Wireless Communication Applications

10.12928/telkomnika.v16i5.10454
Ahmed; German Research Foundation (DFG) Boutejdar , Mohammad A.; Electrical, Telecommunications and, Electronics Engineer Salamin , Mouloud; University M’Hamed Bougara of Boumerdes Challal , Sudipta; Department of Electronics and Communication Engineering Das , Soumia El; Mohammed V University in Rabat Hani , Saad S.; University Sidi Mohamed Ben Abdellah Fès Bennani , P. P; Univrsity of Kalyani Sarkar
A novel single layer, microstrip line fed compact wideband monopole antenna using open loop resonator has been designed and analyzed. The proposed antenna occupies a compact size of only 30 36.5 1.6 mm3. A partial ground plane is employed to enhance the operating bandwidth and reflection coefficient of the proposed antenna. The variations in operating bandwidth of the proposed antenna can be easily controlled by properly adjusting the position of the gap in the open loop resonator.The antenna prototype is fabricated on FR4 substrate with a dielectric constant 4.2. In this design, the antenna exhibits 10dB wide impedance bandwidth of 61% from 2.0174 to 3.7903 GHz.The antenna can be easily fed using a 50 Ω microstrip feed line and it covers the bandwidth requirements of a number of modern wireless communication systems such as IEEE 502.11b WLAN band (2.4 2.5 GHz), extended UMTS (2.5 2.69 GHz), IMT (2.7 2.9 GHz), and IEEE 802.16 Wi MAX band (3.3 3.6 GHz) applications. The desired antenna is designed and simulated using Computer Simulation Technology (CST). An extensive analysis of the antenna parameters (reflection coefficient, radiation pattern, directivity, and VSWR) including surface current distributions is presented and discussed in this paper. Good agreement between simulated and measured result is obtained.
Volume: 16
Issue: 5
Page: 2023-2031
Publish at: 2018-10-01

Feature Extraction Analysis for Hidden Markov Models in Sundanese Speech Recognition

10.12928/telkomnika.v16i5.7927
Intan Nurma; Padjadjaran University Yulita , Akik; Padjadjaran University Hidayat , Atje Setiawan; Padjadjaran University Abdullah , Rolly Maulana; Politeknik Pos Indonesia Awangga
Sundanese language is one of the popular languages in Indonesia. Thus, research in Sundanese language becomes essential to be made. It is the reason this study was being made. The vital parts to get the high accuracy of recognition are feature extraction and classifier. The important goal of this study was to analyze the first one. Three types of feature extraction tested were Linear Predictive Coding (LPC), Mel Frequency Cepstral Coefficients (MFCC), and Human Factor Cepstral Coefficients (HFCC). The results of the three feature extraction became the input of the classifier. The study applied Hidden Markov Models as its classifier. However, before the classification was done, we need to do the quantization. In this study, it was based on clustering. Each result was compared against the number of clusters and hidden states used. The dataset came from four people who spoke digits from zero to nine as much as 60 times to do this experiments. Finally, it showed that all feature extraction produced the same performance for the corpus used.
Volume: 16
Issue: 5
Page: 2191-2198
Publish at: 2018-10-01

Increasing the Detail and Realism in Web3D Distributed World

10.12928/telkomnika.v16i5.10113
Mursid Wahyu; Universitas Ahmad Dahlan Hananto , Ahmad; Universitas Gadjah Mada Ashari , Khabib; Universitas Gadjah Mada Mustofa , Agus; Universitas Gadjah Mada Harjoko
A complex and detailed Web3D world which represented the physical form of an institution is very difficult to be built. To simplify the work, raster images taken from the real structure were heavily utilized. However, this method has resulted in Web3D sites which were low on detail and having minimum level of realism. To overcome this deficiency, it is proposed to maximize the use of polygons. Experiment was done by re-developing the sample world with minimum use of raster images and applying polygons to 92% parts of the site. Site elements were also distributed to three servers to cope with bottleneck problem often occured when using only one server. The result was evaluated in a series of tests to see its viewing capabilities when displayed inside the web browser against various conditions, and it also evaluated in an acceptance test carried out by site users. The majority of testers felt immensely familiar with the details shown by the model as they were able to grab a more close-to-realistic experience like a real-world walk around inside the actual building complex. Problems that often occur whe using only one server ca also be reduced by using distributed world method.
Volume: 16
Issue: 5
Page: 2165-2178
Publish at: 2018-10-01

Adaptive Multi-state Millimeter Wave Cell Selection Scheme for 5G communication

10.11591/ijece.v8i5.pp2967-2978
Mothana L Attiah , Azmi Awang Md Isa , Zahriladha Zakaria , Nor Fadzilah Abdullah , Mahamod Ismail , Rosdiadee Nordin
Millimeter wave bands have been introduced as one of the most promising solutions to alleviate the spectrum secrecy in the upcoming future cellular technology (5G) due the enormous amount of raw bandwidth available in these bands. However, the inherent propagation characteristics of mmWave frequencies could impose new challenges i.e. higher path loss, atmospheric absorption, and rain attenuation which in turn increase the outage probability and hence, degrading the overall system performance. Therefore, in this paper, a novel flexible scheme is proposed namely Adaptive Multi-State MmWave Cell Selection (AMSMC-S) through adopting three classes of mmWave base stations, able to operate at various mmWave carrier frequencies (73, 38 and 28 GHz). Two mmWave cellular Grid-Based cell deployment scenarios have been implemented with two inter-site-distances 200 m and 300 m, corresponding to target area of (2.1 km2) and (2.2 km2). The maximum SINR value at the user equipment (UE) is taken in to consideration to enrich the mobile user experience. Numerical results show an improvement of overall system performance, where the outage probability reduced significantly to zero while maintaining an acceptable performance of the 5G systems with approximately more than 50% of the mobile stations with more than 1Gbps data rate. 
Volume: 8
Issue: 5
Page: 2967-2978
Publish at: 2018-10-01

Hybrid Time-Power Switching Protocol of Energy Harvesting Bidirectional Relaying Network: Throughput and Ergodic Capacity Analysis

10.12928/telkomnika.v16i5.9118
Tran Hoang Quang; Ton Duc Thang University Minh
In this paper, we investigate system performance in term of throughput and ergodic capacity of the hybrid time-power switching protocol of energy harvesting bidirectional relaying network. In the first stage, the analytical expression of the system throughput and ergodic capacity of the model system is proposed and derived. In this analysis, both delay-limited and delay-tolerant transmission modes are presented and considered. After that, the effect of various system parameters on the proposed system is investigated and demonstrated by Monte-Carlo simulation. Finally, the results show that the analytical mathematical and simulated results match for all possible parameter values for both schemes.
Volume: 16
Issue: 5
Page: 1947-1956
Publish at: 2018-10-01

Exact Outage Performance Analysis of Amplify-and-forward-aware Cooperative NOMA

10.12928/telkomnika.v16i5.9823
Dinh-Thuan; Ton Duc Thang University Do , Tu-Trinh T.; Industrial University of Ho Chi Minh City Nguyen
In this paper, new radio access scheme that combines Amplify-and-Forward (AF) relaying protocol and non-orthogonal multiple access (NOMA) system is introduced. In particular, different scenarios for fixed power allocation scheme is investigated. In addition, the outage probability of both weak and strong user is derived and provided in closed-form expressions. Such outage is investigated in high SNR scenario and comparison performance between these NOMA scenarios is introduced. Numerical simulations are offered to clarify the outage performance of the considered scheme if varying several parameters in the existing schemes to verify the derived formulas.
Volume: 16
Issue: 5
Page: 1966-1973
Publish at: 2018-10-01

Combination of Flex Sensor and Electromyography for Hybrid Control Robot

10.12928/telkomnika.v16i5.7028
Muhammad Ilhamdi; Universitas Andalas Rusydi , Muhammad Ismail; Universitas Andalas Opera , Andrivo; National University of Singapore Rusydi , Minoru; Gifu University Sasaki
The alternative control methods of robot are very important to solved problems for people with special needs. In this research, a robot arm from the elbow to hand is designed based on human right arm. This robot robot is controlled by human left arm. The positions of flex sensors are studied to recognize the flexion-extension elbow, supination-pronation forearm, flexion-extension wrist and radial-ulnar wrist.The hand of robot has two function grasping and realeasing object. This robot has four joints and six flex sensors are attached to human left arm. Electromyography signals from face muscle contraction are used to classify grasping and releasing hand. The results show that the flex sensor accuracy is 3.54° with standard error is approximately 0.040 V. Seven operators completely tasks to take and release objects at three different locations: perpendicular to the robot, left-front and right-front of the robot. The average times to finish each task are 15.7 ssecond, 17.6 second and 17.1 second. This robot control system works in a real time function. This control method can substitute the right hand function to do taking and releasing object tasks.
Volume: 16
Issue: 5
Page: 2275-2286
Publish at: 2018-10-01

SHE Control for PV System Connected to the Grid

10.12928/telkomnika.v16i5.9518
Maha; USMBA FST FEZ Khanfara , Rachid EL; USMBA FST FEZ Bachtiri , Oumaima; USMBA FST FEZ Khanfara , Mohammed; USMBA FST FEZ Boussetta , Karima EL; USMBA FST FEZ Hammoumi , Imane; USMBA FST FEZ Idrissi
In this article, we have proposed a new control of a PV system connected to the grid. The goal is to reduce current and voltage harmonicsfor increasing the quality of delivered energy. First, we have modeled a PV panel. Then we have dimensioned the BOOST converter by finding L and C values. Next, we have used Perturb and Observe (P&O) Maximum Power Point Control (MPPT) to improve energy efficiency. Finally, We have developed a control of single-phase H-bridge inverter in order to eliminate the 3rd,5th,7th and 9th harmonics order, and added an LCLTo connect the PV inverter to the grid, an LCL betweenthe inverter and the grid. Theperformance of the proposed system was tested by computing spectrum and THD usingMatlab/Simulink software. The proposed architecture provides better Total Harmonic Distortion (THD) which satisfy the EN50160 requirement the THD must be less than 4.66%. We found that THD was decreased from 61.93% to 0.04%.
Volume: 16
Issue: 5
Page: 2374-2384
Publish at: 2018-10-01

Control Strategy for Distributed Integration of Photovoltaic and Battery Energy Storage System in Micro-Grids

10.12928/telkomnika.v16i5.10249
Alias; Universiti Teknikal Malysia Melaka Khamis , Mohd Ruddin; Universiti Teknikal Malysia Melaka Ab. Ghani , Gan Chin; Universiti Teknikal Malaysia Melaka Kim , Mohd Shahrieel; Universiti Teknikal Malysia Melaka Mohd Aras , Muhammad Aswad; Universiti Teknikal Malysia Melaka Bin Zabide , Tole; Universitas Ahmad Dahlan Sutikno
The micro-grid deployments are growing with independently, power system designers, manufacturers and researchers for the applications where the loads are more efficient association with extra output sources such as Battery Energy Storage System (BESS), and Photovoltaic (PV) systems. Using renewable source as main sources for micro-grid system also can avoid from the pollution to occur. Energy storage when combined with PV system can provide a stronger economic performance, as well as an added benefit of backup power for critical loads. This project proposed control strategies for integration of BESS and PV in a micro-grid. The operation enables the maximum PV and BESS utilization during different operating condition of the micro-grid, grid connected, islanded mode or a process between these two operations. The project will focus on analyzing the performance between photovoltaic system and battery in the simulations of micro-grids system and validate the simulation result using MATLAB/SIMULINK software. After the simulation was analyzed, the understanding of benefit in using renewable energy source as main power supply with support from battery energy storage to supply the power to the loads and power managements is realized in the different modes on micro-grid which is grid connected or islanded states. When the power generation from PV system was not enough to accommodate electric loads, the BESS or from secondary side of transformer will supply the insufficient power.
Volume: 16
Issue: 5
Page: 2415-2427
Publish at: 2018-10-01

An Enhancement Role and Attribute Based Access Control Mechanism in Big Data

10.11591/ijece.v8i5.pp3187-3193
M Meneka , K. Meenakshisundaram
To be able to leverage big data to achieve enhanced strategic insight and make informed decision, an efficient access control mechanism is needed for ensuring end to end security of such information asset. Attribute Based Access Control (ABAC), Role Based Access Control (RBAC) and Event Based Access Control (EBAC) are widely used access control mechanisms. The ABAC system is much more complex in terms of policy reviews, hence analyzing the policy and reviewing or changing user permission are quite complex task. RBAC system is labor intensive and time consuming to build a model instance and it lacks flexibility to efficiently adapt to changing user’s, objects and security policies. EBAC model considered only the events to allocate access controls. Yet these mechanisms have limitations and offer feature complimentary to each other. So in this paper, Event-Role-Attribute based fine grained Access Control mechanism is proposed, it provide a flexible boundary which effectively adapt to changing user’s, objects and security policies based on the event. The flexible boundary is achieved by using temporal and environment state of an event. It improves the big data security and overcomes the disadvantages of the ABAC and RBAC mechanisms. The experiments are conducted to prove the effectiveness of the proposed Event-Role-Attribute based Access Control mechanism over ABAC and RBAC in terms of computational overhead.
Volume: 8
Issue: 5
Page: 3187-3193
Publish at: 2018-10-01

Innovative Model for Logo Counseling Website

10.12928/telkomnika.v16i5.7593
Jacob Daan; Satya Wacana Christian University Engel , Ventje Jeremias Lewi; Harapan Bangsa Institute of Technology Engel , Evangs; Satya Wacana Christian University Mailoa
Logo counseling is a counseling model specifically to treat low spiritual self-esteem problem affecting the life and attitudes of college students. Nevertheless, the problem relies on distance, time, and psychological burdens which preventing face-to-face logo counseling. By reviewing past research regarding online counseling practices, the innovative model for online logo counseling was designed and then demonstrated via logo counseling website. There are four objectives and thirty-five specifications defined in the model. The result showed that logo counseling website is helpful and easy to understand. Further research needed to address the issue of security and confidentiality, furthermore future research needed to examine the integration of text-mining and multimedia analysis techniques to better helping counselors in online counseling intervention.
Volume: 16
Issue: 5
Page: 2111-2117
Publish at: 2018-10-01

Exploiting Outage Performance of Wireless Powered NOMA

10.12928/telkomnika.v16i5.9385
Dinh-Thuan; Industrial University of Ho Chi Minh City Do , Chi-Bao; Industrial University of Ho Chi Minh City Le
Considering a dual-hop energy-harvesting (EH) non-orthogonal multiple access (NOMA) relaying system, this paper considers novel relaying protocol based on time power switching-based relaying (TPSR) and power switching-based relaying (PSR) schemes for two kinds of gain factors regarding amplify-and-forward mode. We introduce novel system model relaying network with impacts of energy harvesting fractions and derive analytical expressions for outage probability for the information transmission link. It confirmed that right selection of power allocation for NOMA to obtain optimal performance as compared study in two considered schemes. We also explore impacts of other key parameters of system to outage performance evaluation for different channel models. Simulation results are presented to corroborate the proposed methodology.
Volume: 16
Issue: 5
Page: 1907-1917
Publish at: 2018-10-01
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