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23,598 Article Results

Recursive Detection of M-Ary Signals over Fast Varying Mobile Communication Channel

10.12928/telkomnika.v11i1.899
Ahmed El-Sayed; German University in Cairo El-Mahdy
          Mobile radio is characterized by a fast time varying channel. Conventional detectors which designed optimal for non-fading channel exhibit a limited performance in fast time varying channel. In this paper a recursive detector for M-ary signals over fast time varying mobile communication channel is introduced. The proposed detector continuously estimates the channel directly within the metric calculation of the log-likelihood function in a recursive manner. The estimation of the channel is performed by the covariance form of the recursive least square approach. The performance of the detector is evaluated in terms of the misdetection probability. The effects of timing and phase offsets on the performance of detector are examined by simulation. Simulation results show that the proposed detector can accommodate the fast time varying channel with adequate performance.
Volume: 11
Issue: 1
Page: 147-154
Publish at: 2013-03-01

Inverter Development as A Boost Converter for DC Microgrid

10.12928/telkomnika.v11i1.917
Budiyanto; University of Indonesia Budiyanto , Rudy; University of Indonesia Setiabudy , Eko Adhi; University of Indonesia Setiawan , Aditya; University of Indonesia Kurniawan
DC boost converter is an essensial equipment in the system of DC microgrid  which has a function as step up voltage. In making a boost converter equipment of power generation, it often encounters a problem within especially in designing of switching transformer, so that it is need  a long development  time and   high  development cost. In order to solve this problem, in this research it has been made a inverter  development  as boost converter which has been done by simulation and experiment. The simulation results show that for an input voltage 10-14 Vdc yields voltage 254 Vdc, while by testing for an input voltage 10-14 Vdc yields voltage 253 Vdc. Either simulation or test result  show that voltage can be applied in the system of dc micro grid for the need of load based switch mode power supply /SMPS. 
Volume: 11
Issue: 1
Page: 249-256
Publish at: 2013-03-01

Modified MVR-CORDIC Algorithm and it’s Application in Attitude Measurement

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2076
Jiang Haitao , Shang Xiaoxing
Aiming at attitude measurement with 51 MCU, The speed and efficiency of basic MVR-CORDIC (Modified Vector Rotational-Coordinate Rotation Digital Computer) are lower, we lists the steps used to measure the heading in rotate mode. Considered the features of the 51-MCU and the MVR-CORDIC algorithm, some new schemes about iteration number and searching algorithm are presented to improve the speed. this modified algorithm is tested and compared in 51-MCU, the experiment result shows that adaptive iteration makes iteration times to 67 percents of the general numbers and the modified searching algorithm reduces 57 percents of the normal iteration time. The experimental results show that the Angle indicator system has high resolution; accuracy of pitch Angle within the ±0.4°; the accuracy of roll within the ±0.4° when pitch angle is not more than 80°, which meet the measuring system accuracy. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2180 
Volume: 11
Issue: 3
Page: 1148-1156
Publish at: 2013-03-01

Colored Ball Position Tracking Method for Goalkeeper Humanoid Robot Soccer

10.12928/telkomnika.v11i1.877
Arif; Universitas Ahmad Dahlan Rahman , Nuryono Satya; Universitas Ahmad Dahlan Widodo
The goalkeeper robot in a robot soccer game must be able to detect position of the ball and block the ball into the goal. Identifying the location of the ball using robot vision becomes very important in addition to the mechanical motion of the robot. This paper proposed method to track colored ball position for goalkeeper robot. First, image is captured with web camera and then color filtering based on HSL color model performed on each image frame in the video. After that, images from filtering process are detected its blob by labeling nearest connected components. The largest blob in image represents the ball. The next step is detection of ball position using 9-Cells coordinate. Ball position coordinate is updated in some period of time and then sends to robot controller to conduct the robot's movements appropriately. Experiment results show that system is able to detect the ball and its position in 9-Cells coordinate which can be used by goalkeeper robot soccer controller to block the ball.
Volume: 11
Issue: 1
Page: 11-16
Publish at: 2013-03-01

Fault Detection in Complex Distribution Network Based on Hilbert-Huang Transform

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2108
Zhongjian Kang , Aina Tian , Yanyan Feng
Traditional distribution network fault location methods often cannot be effectively applied for the structure of the branch in complex distribution network. A new accurate fault location for the single-phase-ground fault in complex distribution network with structure of the branch based on Hilbert-Huang transform was proposed in this paper. First, the distribution network was modeled. The faults on each branch were simulated. The energy characteristics under the branch in a particular frequency band were identified by HHT. Then these energy characteristics were used to train artificial neural networks (ANN).When the energy characteristics of actual fault are inputted, the trained neural network can output the malfunction branch. When the fault branch was determined, using the online fault feature matching method, combined with the genetic algorithm, the precise determination of the distance to fault location in the fault branch can be completed. With combinations of signal processing-Hilbert-Huang transform, artificial neural network and genetic algorithm, the entirely new method was proposed to deal with the problem of fault location in distribution network in this article. The results showed that the method has a good precision and apply to the small current grounding system. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2220
Volume: 11
Issue: 3
Page: 1403-1413
Publish at: 2013-03-01

Motor Noise and Vibration Test Research

10.12928/telkomnika.v11i1.886
Zhongjie; Hebei University of Science and Technology Wang , Jingnan; Hebei University of Science and Technology Zhang , Yongchun; Hebei University of Science and Technology Liang
Some factors, such as friction, vibration, and so on, can result in the fault and abnormal noise in the motor. Based on the detection and analysis of noise and vibration, we can identify and eliminate the faults of the motor. This is helpful not only to ensure the completion of production tasks, but also to prevent accidents. In this paper, we briefly introduce the motor noise generation principle. A laptop computer and LabVIEW software are used to design the experiment system to detect and analysis the noise and vibration of motor. External microphone and computer with sound card constitute noise detection system hardware. Vibration sensor and the data acquisition card constitute vibration detection system hardware. LabVIEW software combined with FFT analysis is used to realize the noise signal acquisition, recording and spectral analysis. Detecting and analyzing the noise of the permanent magnet DC motor and three-phase asynchronous motor proves that the motor noise and vibration detecting experimental platform is fully meet the requirements of motor test and research. This detection and analysis system has a good man-machine interface and strong operability.
Volume: 11
Issue: 1
Page: 87-94
Publish at: 2013-03-01

Characteristics Analysis of HFM Signal over Underwater Acoustic Channels

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2079
YUAN Fei , WANG Wen-Jun , CHENG En
For pulse compression characteristics and not easily affected by noise, linear frequency modulation signal are widely used in underwater acoustic communication. This paper analyzes the characteristics of hyperbolic frequency modulation signal over underwater acoustic channels. Compared with linear frequency modulation signal, hyperbolic frequency modulation has the same performance of strong anti-noise and anti-multipath, what’s more, hyperbolic frequency modulation signal is better resist the influence of doppler. And discussed the influence of doppler on signal, simulation results show that the hyperbolic frequency modulation signal detection rate is better than linear frequency modulation signal in the doppler environment.DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2183
Volume: 11
Issue: 3
Page: 1173-1180
Publish at: 2013-03-01

Chaotic Prediction for Traffic Flow of Improved BP Neural Network

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2140
Yue Hou , Yuemei Mai
A prediction algorithm for traffic flow prediction of BP neural based on Differential Evolution(DE) is proposed to overcome the problems such as long computing time and easy to fall into local minimum by combing DE and neural network . In the algorithm, DE is used to optimize the thresholds and weights of BP neural network, and the BP neural network is used to search for the optimal solution. The efficiency of the proposed prediction method is tested by the simulation of two typical chaotic time series and real traffic flow. The simulation results show that the proposed method has higher precision compared with the traditional BP neural network，so prove it is feasible and effective in the practical prediction of traffic flow. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2324
Volume: 11
Issue: 3
Page: 1682-1690
Publish at: 2013-03-01

Researches on Parameters Calculation of Designing Double-tuned Filter

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2078
HE Yi-hong , SU Heng
Aiming at the question of parameter of double-tuned filter, A new method of designing double-tuned filter was proposed based on resonance frequency, by using the relationship that the impedance of double-tund filter and two parallel single tuned filters is equal and the  resonance frequency of single tuned filter is the zero of the impedance of double-tuned filter. A simulation was established to prove the correctness of this method by using the software MATLAB in a power system. Simulation results show that the double-tuned filter designed in this method works well. All of this had an important guiding significance for the research of double-tuned filter. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2182
Volume: 11
Issue: 3
Page: 1166-1172
Publish at: 2013-03-01

The Effectiveness of Teaching Programme Regarding Prevention and Management Napkin Dermatitis in Allahabad

https://ijphs.iaescore.com/index.php/IJPHS/article/view/4595
Jemy Joseph , Shiju Mathew
The neonates are unique in several ways in comparison with older children and adults which render them highly susceptible to severe dermatological disorders. Skin diseases in infancy and childhood often-present patterns, which may diverge from the same diseases in adults. Infants can get a variety of skin diseases, and some are more common than others. Infants are particularly at risk for developing diaper dermatitis and its potential consequences. It is one of the most common skin problems in infants and children, affecting between 7 and 35 per cent of infants at some point. Diaper rash occurs most commonly in infants between ages nine and 12 months, but can occur at any time the child wears a diaper. The present study was conducted to assess the effectiveness of structured teaching programme on prevention and management of napkin dermatitis in infants’ on mothers residing at Rural Naini, Allahabad. The conceptual framework set up for the study is Conceptual framework based on modified general system theory (Bertalamffy & JW Kenny). The model which has four phases i.e. input, throughput, output and feedback, context, It provide comprehension, systematic and continuous ongoing frame work for program evaluation and hence helped the investigator to assess the effectiveness of structured teaching programme on prevention and management of napkin dermatitis in infants and assess the level of knowledge gained by the mothers regarding prevention and management of napkin dermatitis in infants. In this study various literature was reviewed which includes, the research design selected for the study was pre experimental research design of one group pre-test post-test design. The independent variable was structured teaching programme and dependent variables were level of knowledge of mothers in pre-test and post-test.DOI: http://dx.doi.org/10.11591/ijphs.v2i1.1334
Volume: 2
Issue: 1
Page: 7-16
Publish at: 2013-03-01

Tumors, Neurotransmitters and Pharmacology: Interactions and Implications

https://ijphs.iaescore.com/index.php/IJPHS/article/view/4596
Abdelaziz GHANEMI
Tumors represent a challenge for the modern therapies, and divers studies have shown that different factors are involved in both tumorigenesis and processes of tumor development. Therefore, further investigations and descriptions of inter-influences and interactions between the nervous system, the tumoral process and pharmacotherapies might lead to novel advances and applications, not only in the therapeutical approaches but also in the experimental design.DOI: http://dx.doi.org/10.11591/ijphs.v2i1.1831
Volume: 2
Issue: 1
Page: 17-22
Publish at: 2013-03-01

Architecture Description Approach of Information Systems to System Optimization

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2098
Cao Wei , Fan Xi-quan , Bie Xiao-wu , Liu Gang-feng , Wu Cheng-hai
The comprehensive electronic information systems architecture is an important part of arming information-based construction, so the architecture description approach is needed to be studied with the system optimization simultaneously. In order to support system optimization, an architecture description approach of information systems is studied with the multi-perspective point’s method. Based on the data of the architecture description models, this article will analysis the data form of the description model and the logic relation of the data therefore the architecture description models can be used to optimize information systems architecture.DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2210
Volume: 11
Issue: 3
Page: 1322-1327
Publish at: 2013-03-01

Angular Power Distribution of Wireless Channel in Mine Tunnels

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2110
Yu HUO , Ting-ting WANG , Feng-xue LIU , Zhao XU
The statistical characteristics of the angular power distribution of the wireless channel in mine tunnels are the concern of this paper. Firstly, we develop a ray-based channel model which provides the angular power spectrum (APS) in tunnels. We discuss the allowed rays existing in a tunnel based on the modal theory. The number of the allowed rays is limited. The directions of the rays are discrete. They are influenced by the excitation conditions. And then we deduce the propagation parameters as the functions of the direction of arrival (DOA) for each ray to reduce the computational burden. The model is validated by experimental measurements. Then theoretical results deduced from our model show that APS in the tunnel follows Gaussian distribution. For vertical polarization, the spread of the azimuth angle is more sensitive to the excitation conditions. While for horizontal polarization, the spread of the elevation angle is more sensitive. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2224
Volume: 11
Issue: 3
Page: 1422-1435
Publish at: 2013-03-01

Serum Lipid Profile and Electrocardiographic Changes in Young Smokers

https://ijphs.iaescore.com/index.php/IJPHS/article/view/4598
Uday B. Nayak , Jinzy Mariam George , Pradeep T.V , Naveen Naveen
Smoking represents an important and rapidly growing global cause of cardiovascular mortality and morbidity.Cigarrette smoking is one of the major modifiable risk factors of cardiovascular disease, unless smokers are able to quit,  approximately 40% of them will die prematurely.The need of the hour is timely intervention through smoking cessation.Our study was carried out in young smokers to demonstrate the effects of smoking on lipid profile and electrocardiographic changes. We aimed to study the effect of smoking on lipid profile and electrocardiographic changes in young smokers.The study design was a cross sectional study comprising 75 male smokers and 75 healthy controls.Smoking history and physical examination was done .Fasting sample was analysed for lipid profile and electrocardiograph of all subjects were recorded.The statistical anaylsis between mean values were evaluated by student‘t’ test. Statistical significance was assessed by chi-square test, p<0.001 was considered to be significant.The mean pulse rate,  the mean systolic blood pressure,  abnormal lipid profile and prolonged Qt interval were significantly higher in smokers (p<0.001).We demonstrated significant lipid abnormalities and electrocardiographic changes in young smokers who form an important risk group and target population in whom smoking cessation counseling should be carried out to decrease long term cardiovascular risk.DOI: http://dx.doi.org/10.11591/ijphs.v2i1.1679
Volume: 2
Issue: 1
Page: 33-38
Publish at: 2013-03-01

The research of railway freight statistics system and statistical methods

https://ijeecs.iaescore.com/index.php/IJEECS/article/view/2094
Wu Hua-Wen , Wang Fu-Zhang
EXT is a JavaScript framework for developing Web interfaces, this paper describes the Ext framework and its application in railway freight statistical and analyzing system and Statistical methods. the paper also analyzes the design, function, implementation and so on of the system in detail. As information technology and the requirements of railway transportation organization and operation continue to improve, railway freight statistical and analyzing system improves obviously in the index system, decision analysis and other aspects, better meeting the work requirements. It will play a more important role in the railway transport organization, management, passenger and freight marketing. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2206
Volume: 11
Issue: 3
Page: 1290-1297
Publish at: 2013-03-01
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