Zhang Wei,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 1: January 2013 , pp. 167-172

The switching device turn-on and turn-off process will produce high-frequency electromagnetic interference, based on the finite element method ANSYS software with powerful computing capabilities, has been widely used in complex electromagnetic field calculations. In this paper, ANSYS software to model and analyze the insulated gate bipolar transistor (IGBT) and quantitative distribution of electromagnetic interference (EMI), and for the staff and scientists doing research in electromagnetic field analysis provides an effective reference program. DOI: http://dx.doi.org/10.11591/telkomnika.v11i1.1884

Xianchen Guo, Jun Zheng, Qikun Zhang, Hongchang Liu,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 1: January 2013 , pp. 417-424

Based on the in-depth analysis of issues in dRBAC model, which include the lack of commission depth control in distributed environment, the inefficiency of cascading revocation of the authorization roles and the incapability of judging whether the commission violates the principles of RBAC model before it is done, this paper proposed MD-dRBAC Model, designed trust management mechanism for MD-dRBAC Model, which was used to control the access, established the credible authority commission tree and finally proposed the detection algorithm for implicit authorities upgrading to avoid violation of the least privilege principle in RBAC model Extensive security and performance analysis show that the proposed schemes are highly efficient and secure. DOI: http://dx.doi.org/10.11591/telkomnika.v11i1.1917

FENG Xiancheng, LI Xiaopeng, SI Qinghua,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 2: February 2013 , pp. 948-953

The signal modulation format is a key issue for 40 G DWDM fiber optical communication system , which determines transmission quality and spectral efficiency. Firstly, 他he scheme of key technologies and modulation format (ODB, CSRZ, DRZ, DPSK, DQPSK) of 40G DWDM system is introduced. Through the Q value with OSNR and BER, the theoretical curve between OSNR and BER is given. And then it proposes optical interface parameters requirements of 40G DWDM system. By way of adopting VOA compensation in experimental system,OTU typical spectrum,eye diagram,BER and OSNR performances have been tested and analyzed. Experiment results show that DRZ code have better transmission performance, are suitable for long or middle distance transmission, meet the demand of commercial application. DOI: http://dx.doi.org/10.11591/telkomnika.v11i2.2058

Yiquan Kong,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 2: February 2013 , pp. 954-959

In order to solve the bandwidth allocation unfairness problem in the cloud computing network, one method uses fairness congestion control algorithm, access control list (ACL) and traffic policing and traffic shaping in the paper. The method can rationally solve the problem after analyzing the reason of cloud computing bandwidth allocation unfairness. For illustration, one network video conference example was utilized to show the method in solving bandwidth allocation unfairness problem.The experimental results show network bandwidths are fairly allocated, packet loss ratio and latency is obvious improvement. The method deals with non-adaptive UDP and TCP adaptive flow congestion and provides the end-to-end quality of service over the differentiated services networks, and the bandwidth allocation problem based on fairness in the cloud computing network is solved well. DOI: http://dx.doi.org/10.11591/telkomnika.v11i2.2059

Lakshmi Ravi, S.G. Bharathi dasan,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 409-418

Optimal power flow (OPF) study is conducted on a power system to achieve one of the following objectives: cost/loss minimization or available transfer capability (ATC) calculation in a deregulated environment. Distributed generation (DG) is a small source of electric power conversion from non-conventional energy sources and Hybrid DGs which often the most cost-effective and reliable way to produce power. The optimality of control variables and minimum value of objective functions in OPF study would definitely change when DGs are interconnected to the grid. The change would be respect to the location, quantity and combination of power injection by DGs. On the other hand, FACTS controllers are effective in utilizing the existing of transmission network which is very important especially in a deregulated system. Unified power flow controller (UPFC), a second generation FACTS controller, is well known for minimizing the cost of generation/losses with a good voltage profile as well as for ATC improvement. This paper conducts a detailed OPF study on a 9 bus system for the above mentioned three objectives to analyze the effect of DGs with and without UPFC. From the results, it is found that hybrid DGs along with UPFC yields better performance in many aspects. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.601

Fatimah Arofiati Noor, Ferry Iskandar, Mikrajuddin Abdullah, Khairurrijal khairurrijal,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 477-485

In this paper, we have developed a model of the tunneling currents through a high-k dielectric stack in MOS capacitors with anisotropic masses. The transmittance was numerically calculated by employing a transfer matrix method and including longitudinal-transverse kinetic energy coupling which is represented by an electron phase velocity in the gate. The transmittance was then applied to calculate tunneling currents in TiN/HfSiOxN/SiO2/p-Si MOS capacitors. The calculated results show that as the gate electron velocity increases, the transmittance decreases and therefore the tunneling current reduces. The tunneling current becomes lower as the effective oxide thickness (EOT) of HfSiOxN layer increases. When the incident electron passed through the barriers in the normal incident to the interface, the electron tunneling process becomes easier. It was also shown that the tunneling current was independent of the substrate orientation. Moreover, the model could be used in designing high speed MOS devices with low tunneling currents. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.607

Usman Akram,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 537-544

Retinal images are used for the automated screening and diagnosis of diabetic retinopathy. The retinal image quality must be improved for the detection of features and abnormalities and for this purpose preprocessing of retinal images is vital. In this paper, we present a novel automated approach for preprocessing of colored retinal images. The proposed technique improves the quality of input retinal image by separating the background and noisy area from the overall image. It contains coarse segmentation and fine segmentation. Standard retinal images databases Diaretdb0, Diaretdb1, DRIVE and STARE are used to test the validation of our preprocessing technique. The experimental results show the validity of proposed preprocessing technique. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.615

Doaa M. Atia,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 431-441

As energy demands around the world increase, the need for a renewable energy sources that will not harm the environment is increased. The overall objective of renewable energy systems is to obtain electricity that is cost competitive and even advantageous with respect to other energy sources. The optimal design of the renewable energy system can significantly improve the economical and technical performance of power supply. This paper presents the power management control using fuzzy logic control technique. Also, a complete mathematical modeling and MATLAB SIMULINK model for the proposed the electrical part of an aquaculture system is implemented to track the system performance. The simulation results show that, the feasibility of control technique. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.603

Shuren Wang, Hu Wang,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 505-513

Water inrush disaster is an important factor in restricting safe production of the coal mine. Taking the roadway in seam in Danhou Coal Mine, as the engineering background, according to the spatial relationship of the roadway, the impermeable layer, the fault and the loading conditions, the fault activation mechanical model under the roadway excavation disturbance was built, and the fault activation conditions, roadway water inrush criterion and water inrush three modes were put forward. A three-dimensional numerical calculation models were built by using FLAC3D. Through fluid-solid coupling calculation, the surrounding rock damage and failure, the water inrush channel formation, and the evolution process of water inrush of the roadway excavation approaching the fault were analyzed, moreover, the displacement field, the stress field and the surrounding rock plastic failure characteristics of the roadway were revealed. Furthermore, under the conditions of different water pressure, impermeable rock thickness, fault displacement, and fault dip angles, the roadway water inrush modes and their evolution characteristics were comparatively analyzed. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.611

WeiBing Zhu, Gang Zhou, HeShun Wang,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 499-504

The failure reasons of reciprocating sealing in OPI-1800AWS fracturing pump is analyzed by scanning electron microscope technology (SEMT). The lubrication mechanism of plunger seal friction pair is analyzed by hydrodynamic lubrication theory. During its discharge and suction stroke, the reciprocating sealing friction pair meets the conditions of hydrodynamic lubrication, a certain thickness of oil film can be formed and maintained between the plunger and V-shaped sealing interface, which can lubricate sealing pair, reduce friction and improve lifetime. The axial pressure distribution of the V-shaped sealing are carried out by theoretical analysis and experimental testing. According to the distribution curve of axial pressure, the V-shaped sealing failure and the determination of the number of loops are discussed.  DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.610

Jun Sun, Yan Wang, Xiaohong Wu, Xiaodong Zhang, Hongyan Gao,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 557-563

Lettuce image segmentation which based on computer image processing is the premise of non-destructive testing of lettuce quality. The traditional 2-D maximum entropy algorithm has some faults, such as low accuracy of segmentation, slow speed, and poor anti-noise ability. As a result, it leads to the problems of poor image segmentation and low efficiency. An improved 2-D maximum entropy algorithm is presented in this paper. It redistricts segmented regions and furtherly classifies the segmented image pixels with the method of the minimum fuzzy entropy, and reduces the impact of noise points, as a result the image segmentation accuracy is improved. The improved algorithm is used to lettuce object segmentation, and the experimental results show that the improved segmentation algorithm has many advantages compared with the traditional 2-D maximum entropy algorithm, such as less false interference, strong anti-noise ability, good robustness and validity. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.618

Yingchao Zhang,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 471-476

In this paper, a novel doubly excited brushless generator (DEBG) with outer radial laminated magnetic barrier rotor (RLMB-rotor) for wind power application was designed and analyzed. The DEBG has 10 rotor pole numbers with outer rotor. Its performance is investigated using the 2D transient finite element method. The magnetic fields, torque capability, end winding voltage characteristics, radial magnetic force and energy efficiency were analyzed. All studies in this paper show that the simplicity, reliability, high efficiency and low vibration and noise of the DEBG with outer rotor are attractive for variable speed constant frequency (VSCF) wind power generation system. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.606

Hermagasantos Zein, Yusra Sabri, Ali Mashar,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 625-632

Technically, electricity business under competition structure is more complex than that of vertically integrated one. The main prolems here are how to create an applicable competition framework and to solve electric calculations very quickly to obtain an optimal energi pricing, cost of losses, congestion and transportation costs by less than 15 minutes. This paper proposes a competition framework with the electric calculations, where  a bilateral contract has been accommodated. Optimal energy price in the paper is calculated based on direct method of economic dispatch to obtain the result very quickly. The proposed method has been simulated to a 4-bus system. The simulation results show that the method works well and complies with the expectation. Therefore, electric power business under competition structure can be well realized by the proposed method. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.849

Fitri Maya Puspita, Kamaruzzaman Seman, Bachok M.Taib, Zurina Shafii,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 592-598

This paper will analyze new improved charging scheme with base price, quality premium and QoS networks involved. Sain and Herpers [5] already attempted to obtain revenue maximization by creating charging scheme of internet. The plan is attempted to solve multiple service networks scheme as an optimization model to obtain revenue maximization using our improved model based on [2] and [5]. The results show that improved model can be solved optimally using optimization tool to achieve better revenue maximization. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.623

Andi Muhammad Ilyas, M. Natsir Rahman,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 3: July 2012 , pp. 459-470

Fuel cost of a thermal generator is its own load functions. In this research, Modified Improved Particle Swarm Optimization (MIPSO) is applied to calculate economic dispatch. Constriction Factor Approach (CFA) is used to modify IPSO algorithm because of the advantage to improve the ability of global searching and avoid local minimum so that the time needed to converge become faster. Simulation results achieved by using  MIPSO method at the time of peak load of of 9602 MW, obtained generation cost is Rp 7,366,912,798,34 per hour, while generation cost of real system is Rp. 7,724,012,070.30 per hour. From the simulation result can be concluded that MIPSO can reduce the generation cost of  500 kV Jawa Bali transmission system of Rp 357,099,271.96 per hour or equal to 4,64%. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.880

Li Honglian, Fang Hong, Tang Ju, Zhang Jun, Zhang Jing,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 7: July 2013 , pp. 4004-4011

It is difficult to accurately reckon vehicle position for vehicle navigation system (VNS) during GPS outages, a novel prediction algorithm of dead reckon (DR) position error is put forward, which based on Bayesian regularization back-propagation (BRBP) neural network. DR, GPS position data are first de-noised and compared at different stationary wavelet transformation (SWT) decomposition level, and DR position error data are acquired after the SWT coefficients differences are reconstructed. A neural network to mimic position error property is trained with back-propagation algorithm, and the algorithm is improved for improving its generalization by Bayesian regularization theory. During GPS outages, the established prediction algorithm predictes DR position errors, and provides precise position for VNS through DR position error data updating DR position data. The simulation results show the positioning precision of the BRBP algorithm is best among the presented prediction algorithms such as simple DR and adaptive linear network, and a precise mathematical model of navigation sensors isn’t established. DOI: http://dx.doi.org/10.11591/telkomnika.v11i7.2852

Jun Lai, Mei Xie,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 743-751

As pulmonary CT has a lot of noise produced by thoracic imaging and partial volume effect, it is difficult that the computer segments out the correct blood vessels for plain thoracic CT. Therefore, after a deep investigation into the enhancement, segmentation methods and the upgrading ability of fractional differential operation, the paper proposes an automatic segmentation method for pulmonary vessel in the plain thoracic CT scans. The method steps are: pulmonary CT images have been enhanced with fractional differential operator firstly, and the image regions have been divided into sub-regions based on two control indexes, then a local optimal threshold is used for the vessels segmentation in each sub-region. The experiment results illustrate: the proposed method can segment out more complete low-level vessels, and the obtained vessel networks has more correct detail information. Compared with traditional methods, it has more accurate segmentation ability for pulmonary vessels in plain CT scans. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.864

Huang Wang-jun,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 619-624

Lightning over-voltage amplitude of equipments on different branch nodes of the arterials has been obtained after the modeling and simulation analysis based on the EMTP (electromagnetic transients program) were done on the lightning over-voltage of a 500kV hydroelectric station was with the system’s worst working condition (single-line, single-transforming, and the line tower on the near side of 500kv hydroelectric station’s GIS was struck by lightning.) Thus, precise data have been acquired to select suitable equipments and verify the resisting lightning performance of the station. Finally, reasonable measures (such as reducing pulse resistance of line tower) are proposed to improve the comprehensive lightning resisting level of hydroelectric stations. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.848

Xijun Yan, Xiangwei Meng, Yan Yan,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 788-797

Wireless sensor network has been applied in precision agriculture. This paper takes CC1000 RF as wireless transceiver, MCU MSP430F149 with high performance and Low-Power as the control center of sensor nodes, which can accurately monitor temperature, humidity and light intensity. Meanwhile, choose LM3S6918 which is a high-performance 32-bit ARM and to design sink node. Since the energy of sink node is unlimited, puts forward a new MAC protocol after experimental researches, and gives the specific methods of implementation and deployment. Experiments prove that the WSN has advantages of Lower-Power and stability. It can be competent for monitoring the general agricultural environment. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.869

Lidan Chen,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 654-658

Flame atomic absorption spectrometry (FAAS) was adopted to detect the construction vehicles automatic transmission through simultaneous determination of typical metal elements contents (Copper, Chromium and Iron) in automatic transmission fluid (ATF). Standard curves of Copper, Chromium and Iron were portrayed. Six parallel tests were implemented and the relative standard deviations (RSD) were 2.59%, 2.89% and 2.71% for Copper, Chromium and Iron separately. Additionally, under the same test conditions and analysis methods, contents of Copper, Chromium and Iron in different mileages of construction vehicles automatic transmission were tested. Analysis showed that, with the increase of mileage, the wear degree of construction vehicles automatic transmission increased and the contents of Copper, Chromium and Iron in ATF were also increased follow specific functions for each element under certain driving condition, and the correlation coefficients R were 0.9994, 0.9993 and 0.9997 correspondingly. Finally, results illustrated that FAAS could serve as the rapid and non-destructive method to determine the contents of Copper, Chromium and Iron, and further to achieve the goal of examining the conditions of the major components of automatic transmission. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.853

YANG Zhexi, XUE Huacheng,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 876-882

Cloud computing has been the most popular and promising concept in the new century with no doubt, which is the most important strategy filed to occupy for IT giants. It is said to lead the 3rd IT revolution, so it will affect every organization, enterprise and individual and therefore the process of informatization of China definitely. Literatures about informatization are reviewed in this paper, characters from market angle are concluded, and expectation is drawn to lead Cloud Computing informatization. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.879

Lydia Sari,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 752-762

Punctured convolutional codes are known to have low complexity compared to their non-punctured counterpart, while retaining a good performance. Analyzing the performance of punctured convolutional code can be simplified by using non-punctured equivalent code. In this paper new punctured convolutional codes with rates of 3/8, 3/7 and 3/6 are proposed, and their performances are studied by first constructing non-punctured equivalent codes.  Simulation results show that different puncturing patterns will affect the code performances. Further investigations show that puncturing adjacent bits is to be avoided as it tends to degrade the code performance, as indicated by a decrease of the free distance by 9% and 33% below average for code rates 3/7 and 3/6 respectively. On the contrary, dispersed punctured bits will yield good code performance as indicated in the increase of the free distance by 27% and 32.45% above average for code rates 3/7 and 3/6 respectively. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.865

Gang Yang, Jin Liu,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 812-817

The in-phase and quadrature modulator (IQ modulator) is a key component in modern wireless transmitter. It provides a convenient method for modulating data bits or symbols onto an RF carrier. It has become the architecture of choice for implementing transmitter signal chains for end applications such as cellular, WiMAX, and wireless point-to-point. However, there are several non-ideal aspects of analog IQ modulator, include IQ gain imbalance, imperfect quadrature, and LO leakage. These imperfections will result in image spectral and degrade MER of the modulator, which in turn degrades bit error rate (BER). Gain matching and phase compensation both affect the total amount of image rejection. Factory calibration can detect the IQ gain and phase mismatch in different frequency and store the correction coefficients in nonvolatile memory. The key issue is how to get the exact mismatch. In this paper, a mathematical model of IQ modulator was established and an analytic solution is obtained about how to get the exact mismatch parameters. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.872

Budi Rahmani,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 4: August 2012 , pp. 713-722

Recognizing the traffic signs installed on the streets is one of the requirements of driving on the road. Laxity in driving may result in traffic accident. This paper describes a real-time reminder model, by utilizing a camera that can be installed in a car to capture image of traffic signs, and is processed and later to inform the driver. The extracting feature harnessing the morphological elements (strel) is used in this paper. Artificial Neural Networks is used to train the system and to produce a final decision. The result shows that the accuracy in detecting and recognizing the ten types of traffic signs in real-time is 80%. DOI: http://dx.doi.org/10.11591/telkomnika.v10i4.861

Thin Lai Lai Thein,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 999-1004

A robust method for panorama view reconstruction from multiple viewpoints of the large-scale object is presented. The desired object must be acquired from multiple viewpoints. The information of the feature points of an object is obtained by establishing correspondence between views. We present a robust method based on image mosaicing approach and panorama synthesizing. First, the feature of each object is extracted. Then the corresponding feature points of an object between the images are estimated. The different of minimum threshold value between two images is computed. After that, the full-view of an object is reconstructed by integrating two images based on image mosaicing approach.This research describes how to establish feature correspondences between images accurately and effectively. Image registration technique provides an initial estimation for establishing feature correspondences of point features. The linear solution with the reliable correspondences makes the computation of the geometric transformation between two images, called homography. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1178

Jiejia LI, Rui QU, Yang CHEN,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 960-967

Aiming at the characteristics which variable air volume air conditioning system is multi-variable, nonlinear and uncertain system, normal fuzzy neural network is hard to meet the requirements which dynamic control of multi-variable. In this paper, we put forward a recursive neural network predictive control strategy based on T-S fuzzy model. Through T-S fuzzy recursive neural network predictor on line established controlled object’s mathematical model, and using neural network controller on line corrected information we get, thus to improve control effect. The simulation results show that T-S fuzzy recursive neural network predictive control has stronger robustness and adaptive ability, high control precision, better and reliable control effect and other advantages.  DOI:http://dx.doi.org/10.11591/telkomnika.v10i5.1277 

Zhen-Guo Li,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 919-924

This paper is concerned with analysis for the strengthening effect of carbon fiber-reinforced polymer (CFRP) on steel columns under cyclic lateral loading in thermal environment. Based on the finite element theory of thermo-elastic problem and steel structure stability theory, the hysteretic behavior of axial compression steel columns was studied by using Ansys software. The main variables investigated are:  cyclic lateral loading, temperature, axial compression ratio and ductility. The results show that the CFRP wraps can improve the ultimate cyclic lateral loading and ductility of steel columns prominently in thermal environment which benefit to the anti-seismic capacity of steel structure. The effect of axial compression ratio on ultimate cyclic lateral loading is very obvious, more enhancements achieved with the axial compression ratio increased. While effect of temperature on ultimate cyclic lateral loading is not very obvious below 300℃. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1278 

Liu Bin, Qiu Huayong, Shen Yizhen,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1106-1110

In this paper, we propose the customer attrition early warning model based on data warehouse and data mining technologies, which is achieved and applied in our security company. The modeling variables can be selected by means of the combination with decision tree and the gradual regression in Logistic regression. Then customer attrition early warning model can be constructed based on Logistic regression. The results show that the model can strongly promote the customer attrition capturing rate, push on the building of the company customer marketing management and customer service management organization, and economize the marketing cost. The company profits promotion and trade competitive power can be promised. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1270

Hongsheng Su, Yunchuan Zhang,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 883-890

To aim at the puzzles on faults location in distribution grids, the paper analyzed the distributing characteristics of transient zero-mode currents as the faults occurred, with the aid of correlation theory, a new fault circuit-selection and fault-location method was proposed based on transient zero model current for power distribution grid faults. The method is based on such a fact that the RMS was maximum of fault line transient zero-mode current, and the inner products between it and other line transient zero-mode current were less than zero, in addition, the transient zero-model currents at two sides of the fault point possessed opposite polarity and diverse waveform, and as well as small correlation coefficient closer to zero. In the end, the simulation results show that the proposed method on circuit-selection and fault-location for power distribution grids fault based on transient zero- mode current is correct and effective, and not affected by voltage epoch angle, and grounding resistance, and as well as neutral-point grounding modes. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1289 

Jun Lai, Mei Xie,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1005-1014

When the pathologies are in the close vicinity of the lung wall, the acquisition of the pulmonary nodules depends on accurate segmentation of the lung fields. However, the traditional methods based on pixels intensity can not segment out them correctly. The paper proposes an effective segmentation method based on primary component analysis(PCA) manifold. It used the lung fields relationship in a lung to construct the shape manifold with B-spline interpolation. In the manifold space, according to the position of the affected lung field, a measurement had been used to find an amended position, and it was projected back into the shape space to reconstruct the prior shape. The shape was registered with the affected one and then segmented the original lung section to obtain the correct lung field. The experiment results illustrate that the proposed method has a more correct segmentation ability than the methods based on rolling-ball and pixel intensity. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1266 

Zhixiang Yin, Min Chen,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1111-1116

Time-table problem is a classical NP-complete problem. Algorithm of DNA computing for time-table problem was obtained with introducing the technology of AcryditeTM gel separation. Each class period viewed as a graph vertex was mapped into DNA molecules chain. With the probe coding, the gel column was constructed to arrange the order of DNA chain through biological reaction. The problem was solved by gel column that performs the basic core processing and extraction that makes the result visible. The minimum number of cycles of arrangement was the minimum number of class hours. The simulation results show that the algorithm compared with others is very easy and feasible. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1271

Chengjiang Lu,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1033-1039

The state-of-the-art of near-fault problems in earthquake engineering is comprehensive reviewed. Strong ground motions in the near-fault region exhibit several new characteristics, which cause the attentions of both seismologists and engineers who zealously studied these ground motions during the last two deceases. The investigation on ground motions can interpret the mechanism of the earthquake. Also the ground motions, which are usually assigned by engineers as a type of input loading for seismic design of structures, can sometimes control the final design result. Hence, the characteristics of the loading and the corresponding response of structures are desired for studying. This paper deals with the inherent characteristics of near-fault ground motions and the influences of near-fault ground motions on civil structures. Existing problems are pointed out and work needing further investigation in the future is also discussed. DOI:http://dx.doi.org/10.11591/telkomnika.v10i5.1279 

Hai Xiang Lin,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1151-1156

Scheduling is an important issue in parallel processing. Most scheduling algorithms makes assigns tasks in a direct acyclic graph (DAG) to processors. Usually only the allocation and ordering of tasks are considered, and sometimes communication time is included in the determination of priorities of the tasks, however, communication messages are not explicitly scheduled. Moreover, communication contention plays an increasing important role because of the increased system size of parallel computers. We study the effect of communication scheduling on large interconnection network and try to avoid communication contention. We present a communication scheduling scheme which can be easily included in exiting list-based scheduling algorithms. Experiments show that parallel execution time is reduced as compared to traditional scheduling without explicit communication scheduling. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1350

Xiaofan Wu, Chun Chen, Jiajun Bu,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1077-1080

Wireless sensor network (WSN) has been used widely in vehicular on-board monitoring area. In the scenario of vehicular monitoring, the wireless sensor nodes share similar electromagnet environment. This phenomenon can be used by the sending node to infer the receiver’s noise level. Moreover, the sender can decide the transmitting power accordingly. In this paper, we proposed a interference-aware approaching to control the transmission power of nodes in a vehicular on-board monitoring WSN. By making use of the relationship of noise level on the sender side and the receiver side, the sender node can decide the necessary transmitting power to send a packet successfully. Because the packets are sent at high enough transmission power, the Packet Reception Rate (PRR) is improved. At the same time, the network latency caused by communication failure is reduced. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1351

Tao He,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 1057-1061

The switch control unit module is a critical core control module of the all-electronic computer interlocking system. Switch in the wrong place as the top event, use the Relex software for quantitative analysis of the importance of analysis method and found a key part of the module designs. The weak link in the system design through the use of the ‘2-Vote-2’ modular architecture analysis showed that the system has reached the security requirements of the railway signaling system. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1358 

Wang Jiuhe, Wang Mian, Zhang Li, Yin Hongren,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 5: September 2012 , pp. 940-946

Euler-Lagrange (EL) model of voltage source PWM rectifier is set up based on its model in synchronous dq coordinates. Passivity based controller is designed on the basis of passivity and EL model of voltage source PWM rectifier. Three switching function are educed by passivity based controller. A switching function is only realized in engineering consequently. Voltage source PWM rectifier using passivity based controller has many advantages, such as simpler structure, low total harmonic distortion, and good disturbance rejection performance. Passivity based control law is proved feasible by simulink simulation. DOI: http://dx.doi.org/10.11591/telkomnika.v10i5.1343

Baina He, Yunwei Zhao,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1465-1469

On UHV power transmission lines, when single-phase ground fault happen, it will appear secondary arc on lines, the existence of secondary arc impact on the stable operation of system. The effectiveness of single-pole autoreclosure (SPAR) in maintaining power system stability is largely determined by the speed with which secondary arc extinction, and hence autoreclosure, can be achieved. The paper adopts total harmonic distortion (THD) to judge the status of arc. First, the simulation model of secondary arc is established by ATP software. Then, faulted phase voltage and secondary arc are simulated in different close angle. Last, spectrum characteristics and harmonic content of faulted phase voltage and current are analyzed in different close angle, at the same time, THD of non-faulted phase is also analyzed by Fourier algorithm. Through the fault phase voltage and current simulation and Fourier analysis, which comes to the conclusion that at the peak in the power supply voltage secondary arc is the most difficult to extinguish and the harm to insulation is the greatest. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1411

Fanpeng Yu, Sidong Zhang, Xin Zhou,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1477-1484

P2P file sharing system in campus networks has attracted most of campus users, which can share many useful study and software files and entertainment resource. How to solve “Free Riders" and "Tragedy of Common" widespread problems has become the crucial for P2P system in campus network. In this paper, an incentive mechanism algorithm IMA based on contribution value has been proposed. According to the characteristics of file sharing system in campus network, the rules of the IMA are quantitative for sharing factors such as sharing files size and sharing rate, sharing time and files types. Experimental results and analysis show that the IMA for P2P system can effectively motivate user to share its resource and decease the selfish users, which can take the fairness and efficiency into account in P2P file system. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1397

LI Ming-hai, YIN Hai-tin,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1363-1369

First the study shows flow area can enlarge and turbulence generated by energy loss can reduce as the fuel injection hole chamfering，when spray nozzles are designed in the cone by analyzing and calculating the parameters of a high-power diesel. Then the investigation is created that it is about the pressure maps, velocity maps and discharge maps after the models are imported into the fluid software. The results about the numerical simulation test and verify the validity of the improved structure providing a reference for domestic peers. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1401

Gao Dexin,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1349-1356

This paper concentrates on the solution of state feedback exact linearization zero steady-state error optimal control problem for nonlinear systems affected by external disturbances. Firstly, the nonlinear system model with external disturbances is converted to quasi-linear system model by differential homeomorphism. Using Internal Model Optional Control (IMOC), the disturbances compensator is designed, which exactly offset the impact of external disturbances on the system. Taking the  system and the disturbances compensator in series, a new augmented system is obtained. Then the zero steady-state error optimal control problem is transformed into the optimal regulator design problem of an augmented system, and the optimal static error feedback control law is designed according to the different quadratic performance index. At last, the simulation results show the effectiveness of the method. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1214

Yang Liangen, Zheng Lin,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1403-1408

This paper describes the design of the overall structure about evaluation system of the development process of complex electromechanical device, and analyzes quality evaluation of the stage of scheme design in detail. An evaluation index system of quality of development process is proposed based on resources and conditions, technical status control, management control. Take the evaluation of scheme design stage of ship development as an example, evaluation index system at that stage is established and optimized.  DOI:http://dx.doi.org/10.11591/telkomnika.v10i6.1412

Yuxue Wang, Xianggen Yin, Zhe Zhang, Zhenxing Li,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1280-1286

 For the current transformers (CTs) on the delta side measure the line current instead of the phase current, line current differential protection is adopted in transformers connected in wye-delta mode currently. However, the symmetry feature of inrush current in line current differential protection may invalidate the inrush current restrained criterion. A calculating method of current through delta windings according the measured current from CT is proposed in this paper. Using this calculated current, phase current differential protection can be realized. Based on the method an adaptive second harmonic restrained scheme for magnetizing inrush current is presented. The scheme not only adaptively adjusts the secondary harmonic ratio of restrained current but also guarantees the fast action when transformers with internal faults are no-load energized. Consequently the performance of transformer differential protection is greatly improved. Simulation results in Matlab/Simulink validate the proposed method. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1413

Lu Rongxiu, Yang Hui, Zhang Kunpeng,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1445-1452

In consideration of different characteristic colors of Ions in the P507-HCL Pr/Nd extraction separation system, ions color image feature H, S, I that closely related to the element component contents are extracted by using image processing method. Principal Component Analysis algorithm is employed to determine statistics mean of H, S, I which has the stronger correlation with element component content and the auxiliary variables are obtained. With the algorithm of support vector machine, a component contents soft-sensor model in Pr/Nd extraction process is established. Finally, simulations and tests verify the rationality and feasibility of the proposed method. The research results provide theoretical foundation for the online measurement of the component content in Pr/Nd countercurrent extraction separation process. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1418

Mingwei Leng, Jinjin Wang, Pengfei Wang, Xiaoyun Chen,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1510-1518

Community detection is an important method for analyzing the community structure of real-world networks. Most of the hierarchical agglomeration community detection algorithms are the variations of NM algorithm. In this contribution, we present a new hierarchical agglomeration community detection algorithm, called Community Merging via Community Similarity Measures (CMCSM). The proposed algorithm encompasses three components. It first repeatedly joins communities by using single-node community measure and combination rule. Then it adjusts a few nodes by SHARC which is an advanced label propagation algorithm. Finally, it merges communities by using community similarity measure. Four of most important features of CMCSM are that (1) it requires only a single parameter which is the number of community count, (2) it can prevent single-node communities and monster communities from being created, (3) it is well suited for a wide range of networks and (4) its computation is not expensive. The algorithm CMCSM is demonstrated with real-world and artificial networks, the experiment shows that CMCSM has a more efficient and accurate result of community detection compared with some hierarchical algorithms recently proposed. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1430

Guozhong Li, Li Sui, Gengchen Shi,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1327-1332

For the lack of formula of linear range for S-shaped MEMS planar micro-spring, this paper establishes physical and mathematical model and analysis the material stress-strain angle. The formula is deduced by calculating the strain and rotation of the basic unit of micro-spring tension. Compared with the results of the tests on micro-spring which produced by UV-LIGA process, the formula results is in about 10% higher, providing theoretical guidance for the design and application of S-shaped MEMS planar micro-spring in engineering practice. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1427

Jian-Jun Li,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1242-1248

The life signals are built on harmonic mode for their low frequency, quasi-periodicity, low SNR, and the easy submerged in strong clutter noise. The method for detecting life signal based on adaptive filter and high order statistics is presented, in which neither the Gaussian supposition of the observed signal, nor a prior information about the waveform and arrival time of the observed signal is necessary. The principle of method is to  separate the spectrum of input signal into many narrow frequency bands, whose Sub-band signal  is followed by a short-time estimation of higher-order statistics so as to suppress Gaussian noises. Simulated results show that the method can effectively detect life signals from noise with good convergence speed and stability, and greatly improve the signal quality with respect to LMS method. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1597 

Ting Zhang, Xiu-Li Tu, Xian-Ming Wang, Xin-Wei Zha,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1227-1234

In a recent paper [CHIN. PHYS. LETT. Vol.26,No.7(2009)070306 ], DONG et al. proposed a scheme for probabilistic controlled teleportation of a triplet W state using combined non-maximally entangled channel of two Einstein–Podolsky–Rosen (EPR) states and one Greenberger–Horne–Zeilinger (GHZ) state. In this paper ,only using one Einstein–Podolsky–Rosen (EPR) state and one Greenberger–Horne–Zeilinger (GHZ) state,the scheme for probabilistic controlled teleportation of a triplet W state is presented. Furthermore, Comparing with the widely used Bell-State measurement, Alice performs orthogonal complete basis measurement in the current work. Then Bob can faithfully reconstruct the original state by performing relevant unitary transformations. The total probability of successful teleportation is only dependent on channel coefficients of EPR state and GHZ state. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1546

Qiliang Li, Yong Zhang, Ziyang Wang, Ran Zeng, Tianshu Wang, Miao Hu,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1198-1206

In this paper, we perform a theoretical study of processes that demonstrates additional time delay obtained by remodeling Brillouin gain spectrum, and we also study the main influence factors on pulse time delay and broadening, as well as analyze the ways which increases the delay, and further suppresses pulse broadening. The results show that by remodeling Brillouin gain spectrum, one obtains 25% delay improvement over the single intrinsic Brillouin gain spectrum; by deriving the expression of broadening factor, one finds that the increase of intrinsic SBS resonance linewidth leads to the decrease of the broadening quantity which corresponds to the maximum delay. Moreover, the increase of the peak power of absorption spectrum further leads to an increase of pulse delay. When the normalized frequency shift is below a certain value, probe pulse can be compressed; When the second-order gain is positive, pulse will be compressed; when the second-order gain is negative, pulse will become broad. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1543

Meng Bin, Ruan Jian, Li Sheng,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 10, No 6: October 2012 , pp. 1179-1188

Since the conventional electro-mechanical converter of 2D valve had problems of step lose due to its small tooth-pitch angle, a novel rotary electromagnet with large tooth-pitch angle and coreless rotor structure was proposed. Combined with the approaches of magnetic circuit analysis, finite element simulation and experimental study, the static and dynamic characteristics of electromagnet including torque-angle characteristics, frequency response and step response were studied. The experimental results are in a close agreement with the simulated results. The electromagnet has sinusoidal torque-angle characteristics and good dynamic response. The maximum static torque is approximately 0.083N.M, and its frequency width is about 125Hz/-3dB, 130Hz/-90°, respectively, and the rise time is about 5.5 ms. It is appropriate to be used as the electro-mechanical converter of 2D proportional valve. DOI:http://dx.doi.org/10.11591/telkomnika.v10i6.1446 

Lin Xu, Yang Han,

Indonesian Journal of Electrical Engineering and Computer Science, Vol 11, No 1: January 2013 , pp. 484-493

This paper presents a critical survey of the reference current generation (RCG) methods for harmonic and reactive power compensation for the electrical distribution systems. A critical review of the p-q method, the d-q(id-iq) method, the p-q-r method, the UPF method and the FBD method are presented for the sake of comparison. In order to mitigate the deficiencies of these existing methods, the modified d-q method, the modified p-q-r method, and the modified p-q method are also presented. The MATLAB simulation of these algorithms is carried out for different grid voltage and load conditions scenarios. It is found that, all these algorithms show similar performance in case of ideal grid voltage scenario. In case of grid voltage unbalance or harmonics, the difference in steady state compensation accuracy among these algorithms is presented. DOI: http://dx.doi.org/10.11591/telkomnika.v11i1.1675