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Nourqolipour R.,University Putra Malaysia | Shariff A.R.B.M.,University Putra Malaysia | Ahmad N.B.,National Space Agency of Malaysia ANGKASA | Balasundram S.K.,University Putra Malaysia | And 3 more authors.
Environmental Earth Sciences | Year: 2015

This study addresses resolution of a multi-objective land allocation problem and simulation of land change in the south west of Selangor state, Malaysia. The landscape experiences three conflicting objectives of land change, including urban/built-up development, oil palm development, and forest protection. The three conflicting objectives were simultaneously evaluated through developing three distinct sets of driving factors of land change to find a compromised solution to satisfy the requirements of all objectives. The likely patterns of land change were then simulated for the year 2020 based on transitions observed in two periods 1997–2002 and 1997–2008 under a modeling framework that integrates Multi-Criteria Evaluation (MCE), Cellular Automata (CA), and Markov chain analysis. Results showed that in multi-objective land allocation procedure the highest suitability values were given to urban development, oil palm development, and forest protection objective, respectively. Analysis of transition observed showed that although oil palm land use had experienced the highest expansion among other land classes until the year 2002, urban/urban related/built-up land category has experienced the biggest growth in the landscape between 2002 and 2008. Analysis of simulation results revealed that the urban/urban related/built-up areas would highly expand by the year 2020 at the expense of loss of other land categories. Simulations also showed that natural forest covers still could experience more loss than gain by the year 2020 while the loss rate would be lower than the period 2002–2008 but still higher than the period 1997–2002. Results demonstrated an ongoing, but lesser pressure on the natural rainforests in the coming years. © 2015, Springer-Verlag Berlin Heidelberg. Source

Mee J.W.S.,National Space Agency of Malaysia ANGKASA
International Conference on Electric Power Systems, High voltages, Electric machines, International conference on Remote sensing - Proceedings | Year: 2010

The knowledge of Modulation Transfer Function (MTF) for a degraded image provides a mean to compensate for the image degradation, which improves the image quality in terms of sharpness. MTF compensating is in the image restoration; hence it is fundamentally an ill-posed problem. This paper proposes a stable and flexible filtering technique that executes an optimal tradeoff between sharpness and noise to warrant an acceptable result of image restoration. The MTF compensating is performed through a modified Wiener filter, and can be reduced to a well-posed problem by incorporating the regularization method. The modified Wiener filter employed the L-curve method for selection of optimal regularization parameter, and introduces an inverse control and smooth control parameter that allows freedom of tuning when the importance of image sharpness versus noise is being compromised. The data sets used in the analysis were synthetically blurred remotely-sensed images simulated from Level-2A product of IKONOS. The results by modified Wiener filter were analyzed and presented, they were found to be able to reduce the Mean Square Error by more than 50% with respect to the original image, and it results in a significant improvement of spatial image quality. Source

Suparta W.,National University of Malaysia | Putro W.S.,National University of Malaysia | Singh M.S.J.,National University of Malaysia | Asillam M.F.,National Space Agency of Malaysia ANGKASA
Advanced Science Letters | Year: 2015

To develop a successful model of Mesoscale Convective System (MCS) for space activity plan, we characterized the surface meteorological data (pressure, temperature, relative humidity) and precipitable water vapor (PWV) over Tawau, Malaysia. Global Positioning System (GPS) and surface meteorological data from 1 January 2009 to 30 December 2011 are processed in this analysis. We compared the PWV between GPS and Radiosonde for Tawau on a weekly basis for the year 2011 and found a strong relationship. For a three-year observation, the air pressure was decreased when the temperature was getting cold as well as for the PWV parameter and vice versa. From our analysis, the variation of surface meteorology and PWV were observed to be high during DJF (December, January and February) months which weredue to winter monsoon and frequent increasing of rainfall. However, the dry or clear season is observed to occur obviously in the end of May until August of 2009 to 2011.Based on this preliminary result, we suggest that the characteristics of meteorological phenomena should be properly treated to study the nature of MCS over the region. © 2015 American Scientific Publishers, All rights Reserved. Source

Zavvari A.,National University of Malaysia | Islam M.T.,National University of Malaysia | Anwar R.,National University of Malaysia | Abidin Z.Z.,University of Malaya | And 2 more authors.
Experimental Astronomy | Year: 2016

The e-CALLISTO system is a worldwide network that aims to observe solar radio emission for astronomical science. CALLISTO instruments have been deployed worldwide in various locations that together can provide continuous observation of the solar radio spectrum for 24 h per day year-round. Malaysia-UKM is a strategic equatorial location and can observe the Sun 12 h per day. This paper gives an overview of the spectrum allocation for radio astronomy, which falls in the specified operating frequency band of the CALLISTO spectrometer. The radio astronomy bands are analyzed at the Malaysia-UKM station according to the International Telecommunication Union recommendations. Some observational results are also presented in this paper. © 2015, Springer Science+Business Media Dordrecht. Source

Rokunuzzaman M.,National University of Malaysia | Islam M.T.,National University of Malaysia | Yatim B.,National University of Malaysia | Asillam M.F.,National Space Agency of Malaysia ANGKASA
International Journal of Microwave and Optical Technology | Year: 2014

A multiband microstrip antenna is proposed in this paper. By using a circular slot at the ground plane, the circular radiation at the antenna frequency resonances has been achieved. A patch is designed with a coupled U-shaped line. To gain resonance at the lower frequency, a microstrip line is introduced at the middle of the circular slot. The assessment of the proposed antenna shows good agreement for gaining circular radiation pattern. © 2014 Iamot. Source

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