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28,451 Article Results

Adaptive Fuzzy Sliding Mode Control for a Class of Nonlinear System

10.12928/telkomnika.v13i4.1898
Xue; China University of Geosciences Xiao , Zheng; Nanyang Normal University Zheng , Dong; China University of Geosciences Haobin
For a class of nonlinear system with parameter perturbation and external disturbance, adaptive fuzzy control can be used to approach the system unknown functions to reduce the control input and the steady-state error. And an adaptive switch control gain whose adaptive law is decreasing function is designed to weaken the system chattering, the switch gain of estimate will increase on the basis of the original without decreasing with the elimination of interference. If system is interferenced many times. Against the shortcomings, this paper proposes an improved adaptive law that can weaken the system chattering effectively while maintaining the strong robustness. The simulation results by tests show that this method is correct and effective.
Volume: 13
Issue: 4
Page: 1263-1269
Publish at: 2015-12-01

Design and Implementation of Network Public Opinion Analysis System

10.12928/telkomnika.v13i4.2811
Ma; Xi’an International University Junhong , Liao; Xi’an International University Na
Network public opinion analysis is an important way of information analysis processing. This paper based on the research of the related technologies, designs and realizes a new network public opinion analysis system. System mainly includes network data fetching part, fetching the data processing part, analyzes the processed data part and display part of the public opinion analysis results. In the document extraction part, used the web crawler technology, Larbin web crawler to realize the collection of web content; In public opinion information analysis part, the implementation of the new topic adopts an improved Single - Pass clustering algorithm. This algorithm is using of multi-center, using the title and body of the vector to compared two-way ,that is better reflect the dynamics of public opinion topics. Finally, in the network environment of a university, we have the tests repeatedly. The results show that the new public opinion analysis system running is stable and has good efficiency. The thesis has certain value for the development of other information analysis systems in the Internet.
Volume: 13
Issue: 4
Page: 1368-1375
Publish at: 2015-12-01

A New Algorithm for Protection of Small Scale Synchronous Generators Against Transient Instability

10.11591/ijeecs.v16.i3.pp454-462
Zinat Khosravi , Alireza Saffarian
Today, installation of small generators has been increased because of their considerable benefits in distribution systems in distributed generation. One of the most important problems for transient stability is the effects of the faults of system. Small scale generators have low constant inertia and protection relays have slow performance in distribution systems. Therefore transient instability is a probable phenomenon for the systems with these generators. In this paper, dynamic response of generator has been studied in different fault conditions and then by introducing the concept of " critical fault clearing time ", the sensitivity of this time to the fault type and also fault location parameters have been studied. Then a new protection scheme has been proposed to prevent of transient instability for small scale generator. This protection scheme uses a new evolutionary algorithm based on the active power of generator and critical fault clearing time. The proposed relay can prevent of wrong and unwanted performance. Furthermore it can disconnect the generator from the system in three phase fault near of the bus-bar before its instability. Simulation results show reliable performance of the proposed relay against system transients.
Volume: 16
Issue: 3
Page: 454-462
Publish at: 2015-12-01

Text Mining Research Based on Intelligent Computing in Information Retrieval System

10.12928/telkomnika.v13i4.1788
Yong; ChongQing Technology and Business Institute Li
With the popularity and rapid development of the Internet, web text information has rapidly grown as well. To address the key problem of text mining, text clustering is investigated in this study. The shuffled frog leaping algorithm as a new type of swarm intelligence optimization algorithm can be used to improve the performance of the K-means algorithm, but the shuffled frog leaping algorithm is influenced by its moving step length. On the basis of this information, the shuffled frog leaping algorithm is improved, and the K-means clustering algorithm based on the improved shuffled frog leaping algorithm is introduced. Experiment results show that the proposed scheme can enhance the ability of searching for the optimal initial clustering center and can effectively avoid instability in the clustering results of the K-means clustering algorithm. The proposed scheme also reduces the chances of the algorithm falling into the local optimum. The performance of the proposed clustering scheme is found to be better than that of the clustering algorithm based on the shuffled frog leaping algorithm.
Volume: 13
Issue: 4
Page: 1384-1389
Publish at: 2015-12-01

A Novel Image Segmentation Algorithm Based on Graph Cut Optimization Problem

10.12928/telkomnika.v13i4.1178
Zhang; Chongqing University Guang-hua , Xiong; Chongqing University Zhong-yang , Li; Chongqing University Kuan , Xing; Chongqing University Chang-yuan , Xia; Chongqing University Shu-yin
Image segmentation, a fundamental task in computer vision, has been widely used in recent years in many fields. Dealing with the graph cut optimization problem obtains the image segmentation results. In this study, a novel algorithm with weighted graphs was constructed to solve the image segmentation problem through minimization of an energy function. A binary vector of the segmentation label was defined to describe both the foreground and the background of an image. To demonstrate the effectiveness of our proposed method, four various types of images were used to construct a series of experiments. Experimental results indicate that compared with other methods, the proposed algorithm can effectively promote the quality of image segmentation under three performance evaluation metrics, namely, misclassification error rate, rate of the number of background pixels, and the ratio of the number of wrongly classified foreground pixels.
Volume: 13
Issue: 4
Page: 1337-1342
Publish at: 2015-12-01

Alternative Technique reducing complexity of Maximum Attribute Relation

10.12928/telkomnika.v13i4.2179
Iwan; Universitas Ahmad Dahlan Tri Riyadi Yanto , Imam; Universitas Ahmad Dahlan Azhari
Clustering refers to the method grouping the large data into the smaller groups based on the similarity measure. Clustering techniques have been applied on numerical, categorical and mix data. One of the categorical data clustering technique based on the soft set theory is Maximum Attribute Relation (MAR). The MAR technique allows calculating all of pair multi soft set made. However, the computational complexity is still an issue of the technique. To overcome the drawback, the paper proposes the alternative algorithm to decrease the complexity so get the faster response time. In this paper, to get the similar results as MAR without calculating all pair of soft set is proved. The alternative algorithm is implemented in MATLAB Software, and then experimental is run on the 10 benchmark datasets. The results show that the alternative algorithm improves the computational complexity in term of response time up to 36.46%
Volume: 13
Issue: 4
Page: 1361-1367
Publish at: 2015-12-01

Energy-efficient Routing Model Based on Vector Field Theory for Large-scale Wireless Sensor Networks

10.12928/telkomnika.v13i4.1847
Ming; Nanjing University of Science and Technolog Li , Huanyan; Nanjing University of Science and Technolog Qian , Min; California State University Northridge Xu
Routing design is a key issue for large-scale wireless sensor networks (WSNs). Energy consumption associated with allocated resources should be considered. This paper proposes the integration of an energy-efficient model, which is based on vector field theory, in large-scale WSNs. Source nodes in WSNs have the characteristics of source points in a vector field, whereas sink nodes could be characterized as gathering points. Our scheme demonstrates that we can solve a set of partial differential equations in electrostatic theory to determine the routes that result in energy efficiency. Thus, the routing problem in WSN for energy efficiency becomes a typical PDE solution. Our simulation results show significant improvement in energy consumption. Compared with the traditional shortest path approach, the proposed model shows considerable improvement in the lifetime of the network.
Volume: 13
Issue: 4
Page: 1251-1262
Publish at: 2015-12-01

Recognition of Emotions in Video Clips: The Self-Assessment Manikin Validation

10.12928/telkomnika.v13i4.2735
Dini; Kulliyyah of Information and Communication Technology Handayani , Abdul; Kulliyyah of Information and Communication Technology Wahab , Hamwira; Kulliyyah of Information and Communication Technology Yaacob
Many research domains use video contents as stimuli for study on human emotions. A video content within a particular genre or a specific theme evokes dynamic emotions that are highly useful in many research fields. The present study proposed a set of video-clip stimuli that embody four emotions under specific genres of movies, namely happiness, calmness, sadness and fear. Two experiments (a preliminary and a validation) were conducted in order to validate the video clips. Self-Assessment Manikin was utilized to rate the videos. All the video clips were rated with respect to valence and arousal judgment. In the preliminary experiment, the video clips were rated in terms of how clearly the expected emotions were evoked. The validation experiment was conducted to confirm the results from preliminary experiment, and only video clips with high recognition rates were included into data set.
Volume: 13
Issue: 4
Page: 1343-1351
Publish at: 2015-12-01

A New Strategy of Direct Access for Speaker Identification System Based on Classification

10.12928/telkomnika.v13i4.2017
Hery; Data and Software Engineering Research Group School of Electrical Engineering and Informatics, Institut Teknologi Bandung Heryanto , Saiful; Data and Software Engineering Research Group School of Electrical Engineering and Informatics, Institut Teknologi Bandung Akbar , Benhard; Data and Software Engineering Research Group School of Electrical Engineering and Informatics, Institut Teknologi Bandung Sitohang
In this paper, we present a new direct access strategy for speaker identification system. DAMClass is a method for direct access strategy that speeds up the identification process without decreasing the identification rate drastically. This proposed method uses speaker classification strategy based on human voice’s original characteristics, such as pitch, flatness, brightness, and roll off. DAMClass decomposes available dataset into smaller sub-datasets in the form of classes or buckets based on the similarity of speaker’s original characteristics. DAMClass builds speaker dataset index based on range-based indexing of direct access facility and uses Nearest Neighbor Search, Range-Based Searching, and Multiclass-SVM Mapping as its access method. Experiments show that the direct access strategy with Multiclass-SVM algorithm outperforms the indexing accuracy of Range-Based Indexing and Nearest Neighbor for one to nine percent. DAMClass is shown to speed up the identification process 16 times faster than sequential access method with 91.05% indexing accuracy.
Volume: 13
Issue: 4
Page: 1390-1398
Publish at: 2015-12-01

Power Characteristics of Wireless Charging for Sensor Networks in Tunnels

10.12928/telkomnika.v13i4.3105
Xiaoming; China University of Mining and Technology Liu , Enjie; China University of Mining and Technology Ding , Duan; China University of Mining and Technology Zhao , Youfang; China University of Mining and Technology Yang
In order to generate wireless microwave power charging technology in coal mine tunnels, it is necessary to know the power characteristics of wireless electromagnetic wave along the tunnel walls. In this paper, the experimental results of narrowband wireless electromagnetic wave propagation measurements are presented, and a statistical model of the power characteristics at 2.4 GHz in real rectangular mine tunnels is proposed. Two standard half-wave dipole antennas were used to perform the field experiments in tunnels with different wall materials. A 10-meter wireless charging distance belongs to the free-space propagation zone. The path loss exponents rely heavily on the location of the receiver and antenna polarizations. To obtain more power, the locations of the receiver should match the corresponding polarizations.
Volume: 13
Issue: 4
Page: 1180-1186
Publish at: 2015-12-01

Power Transformer Incipient Faults Diagnosis Based on Dissolved Gas Analysis

10.11591/ijeecs.v16.i3.pp409-416
Osama E. Gouda , Saber M. Saleh , Salah Hamdy EL-Hoshy
Incipient fault diagnosis of a power transformer is greatly influenced by the condition assessment of its insulation system oil and/or paper insulation. Dissolved gas-in-oil analysis (DGA) is one of the most powerfull techniques for the detection of incipient fault condition within oil-immersed transformers. The transformer data has been analyzed using key gases, Doernenburg, Roger, IEC and Duval triangle techniques. This paper introduce a MATLAB program to help in unification DGA interpretation techniques to investigate the accuracy of these techniques in interpreting the transformer condition and to provide the best suggestion for the type of the fault within the transformer based on fault percentage. It proposes a proper maintenance action based on DGA results which is useful for planning an appropriate maintenance strategy to keep the power transformer in acceptable condition. The evaluation is carried out on DGA data obtained from 352 oil samples has been summarized into 46 samples that have been collected from a 38 different transformers of different rating and different life span.
Volume: 16
Issue: 3
Page: 409-416
Publish at: 2015-12-01

Evaluation of the Modernization of Hydraulic Projects Management Compact-Center-Point Triangular Whitenization Weight Function

10.12928/telkomnika.v13i4.2805
Li; Hohai University Lijie , Wang; Hohai University Xiao , Zhang; Hohai University Lina
In the actual analysis of grey clustering evaluation, it has been found that the length of the grey clustering interval is partially larger, which is determined by the method of grey clustering evaluation based on the center-point triangular whitenization weight function. In order to solve this problem, a new grey evaluation method based on reformative triangular whitenization weight function is researched. The existing end-point triangular whitenization weight function and center-point triangular whitenization weight function are revised, and a new compact-center-point triangular whitenization weight function is constructed. Then the rules for grey category intervalof the three triangular whitenization weight functions are compared, and an example about the evaluation of the modernization of hydraulic projects management is proposed for analyzing the three methods to further verify that the improved grey clustering evaluation method based on the compact-center-point triangular whitenization weight function is feasible and effective. The results show that the compact-center-point triangular whitenization weight function is superior to both the end-point triangular whitenization weight function and the center-point triangular whitenization weight function.
Volume: 13
Issue: 4
Page: 1478-1485
Publish at: 2015-12-01

Layer Recurrent Neural Network based Power System Load Forecasting

10.11591/ijeecs.v16.i3.pp423-430
Nikita Mittal , Akash Saxena
This paper presents a straight forward application of Layer Recurrent Neural Network (LRNN) to predict the load of a large distribution network. Short term load forecasting provides important information about the system’s load pattern, which is a premier requirement in planning periodical operations and facility expansion. Approximation of data patterns for forecasting is not an easy task to perform. In past, various approaches have been applied for forecasting. In this work application of LRNN is explored. The results of proposed architecture are compared with other conventional topologies of neural networks on the basis of Root Mean Square of Error (RMSE), Mean Absolute Percentage Error (MAPE) and Mean Absolute Error (MAE). It is observed that the results obtained from LRNN are comparatively more significant.
Volume: 16
Issue: 3
Page: 423-430
Publish at: 2015-12-01

Image Encryption using Simple Algorithm on FPGA

10.12928/telkomnika.v13i4.1787
Barlian Henryranu; University of Brawijaya Prasetio , Eko; University of Brawijaya Setiawan , Adharul; University of Brawijaya Muttaqin
Data security becomes one of the things that need to be considered. The Sum of Product (SOP) Encryption is one of simple algorithm. The SOP encryption is not a public-key system to encrypt data. it is almost unbreakable through brute force method and vulnerable to attack because the encryption models have a fixed pattern. However, this drawback can be avoided through the compression process to remove the pattern file. SOP encryption algorithm can use a Boolean algebra combination functions such as AND gate and OR gate. Simple algorithm in hardware language VHSIC Hardware Description Language (VHDL) is on data bits level. The purpose of this research is implementation of image encryption algorithm to produce a quick image encryption system. From result test, the image processing time without encryption average 4.999ns/px and 13.51ns/px with encryption.
Volume: 13
Issue: 4
Page: 1153-1161
Publish at: 2015-12-01

The Comparison of Access Point Signal Gain with Beverage Cans

10.11591/ijict.v4i3.pp124-130
Ni Wayan Sri Ariyani
Computer network development depends on the development of information technology and communication. Several things as the reasons to develop the technology of computer network are implementing communication flexibly which in this case in the theory of computer network is to build wireless network communication. The existence of wireless communication as the comparison against wired network, having different impairment compared to wired communication. One of which is the weakening of wireless signal strength towards the ongoing communication distance. Therefore in wireless communication currently plenty of it being implemented, to handle the occurring impairment due to distance influence, it is needed for signal amplifier device. One of signal amplifier that can be used in the surroundings which is economical and practical is by using used beverage can.
Volume: 4
Issue: 3
Page: 124-130
Publish at: 2015-12-01
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