Time filter

Source Type

Yogyakarta, Indonesia

Jidin A.,University Technical Malaysia Melaka | Jidin A.,University of Technology Malaysia | Idris N.R.N.,University of Technology Malaysia | Yatim A.H.M.,University of Technology Malaysia | And 3 more authors.
IEEE Transactions on Industrial Electronics | Year: 2011

A dynamic overmodulation strategy for fast dynamic torque control in direct torque control (DTC)-hysteresis-based induction machine is proposed. The fastest dynamic torque response with a six-step mode can be achieved in the proposed method by switching only the most optimized voltage vector that produces the largest tangential component to the circular flux locus. This paper also discusses the performance of dynamic torque control in basic DTC in order to justify on how the proposed selected voltage vector results in excellent dynamic torque performance. The main benefit of the proposed method is its simplicity, since it only requires a minor modification to the conventional DTC-hysteresis-based structure and does not require a space vector modulator. To verify the feasibility of the proposed dynamic overmodulation strategy, simulation and experimentation, as well as comparison with the conventional DTC scheme, are carried out. Results showed a significant improvement in the dynamic torque response when compared to the conventional DTC-hysteresis-based method. © 2009 IEEE. Source

Soetedjo H.,Ahmad Dahlan University
Sensors and Transducers | Year: 2011

The detections have been carried out to the nitrocellulose membrane (wet and dry condition) using a self-construction of polarized reflection spectroscopy. The measurement was done by illuminating the sample at an incident angle of 70° using a visible light source and then analyzing the reflected light off the sample received by the detector of spectrometer. From the investigation, the change of water content introduced to the membrane has been observed respects to the observation time. The water molecules present in or left the porous of membrane could be detected through the investigating of reflected intensities obtained from the measurement. Copyright © 2011 IFSA. Source

Sulisworo D.,Ahmad Dahlan University
International Journal of Emerging Technologies in Learning | Year: 2012

Collaboration has become one of an essential skill necessary for effective functioning in society in the new era. As a consequence, the learning strategy at the higher education should consider this shifting. Web 2.0 technology is a new trend in communication technology that has become a basis of the new generation internet to make it a more mature and distinctive medium of communication. The problem is how to bring the offline learning using cooperative learning based on classroom to the online learning using this wiki. The learning design on this topic will give wide opportunity to access learning that more suitable to the new skill in the new era. Wikispaces is one of wiki facilities that operated in the web based. This wiki is so simple but suitable for collaborative learning. The learning scenario is Jig Saw approach modified to fit in the online collaborative learning environment. This technique, including two different treatments with different small groups in order to help learning and improving cooperation between students. Using this structure, students are responsible for share their skill or knowledge each other material. Source

Yanto I.T.R.,Ahmad Dahlan University
International Journal of Software Engineering and its Applications | Year: 2013

Clustering is the problem of identifying the distribution of patterns and intrinsic correlations in large data sets by partitioning the data points into similarity classes. In this paper, we study on the problem of clustering categorical data, where data objects are made up of non-numerical attributes. We propose MECC (Minimum Error Classification Clustering), an alternative technique for categorical data clustering using VPRS taking into account minimum error classification. The technique is implemented in MATLAB. Experimental results on two benchmark UCI datasets show that MECC technique is better than the baseline categorical data clustering techniques with respect to selecting the clustering attribute © 2013 SERSC. Source

Sutikno T.,Ahmad Dahlan University | Sutikno T.,University of Technology Malaysia | Idris N.R.N.,University of Technology Malaysia | Jidin A.,Hang Tuah University
Renewable and Sustainable Energy Reviews | Year: 2014

The first and the most important step in solving the environmental problems created by cars with internal combustion engines is research and development of electric vehicles. Selection of a proper drive and optimal control strategy of electric vehicles are the major factors to obtain optimal energy management in order to extend the running distance per battery charge. This paper presents a brief review of direct torque control (DTC) of induction motors (IM) as well as its implementation for electric vehicle (EV) applications. First, the basic DTC technique based on hysteresis controllers will be introduced, and then an overview of the major problems in a basic DTC scheme will be presented and explained, as well as some efforts for improving the technique. The main section presents a critical review of DTC for EV applications, taking into consideration the vehicle mechanics and aerodynamics of electric vehicles. The review is very important to provide guidelines and insights for future research and development on the DTC of IM drives for sustainable reliability and energy efficient EV applications. © 2014 Published by Elsevier Ltd. All rights reserved. Source

Discover hidden collaborations