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Kadri S.,Sultan Idris University of Education | Wan Aziz W.N.S.,Sultan Idris University of Education | Hashim M.H.,National Space Agency of Malaysia ANGKASA | Jaafar R.,Sultan Idris University of Education | Yaacob M.I.H.,Sultan Idris University of Education
Applied Mechanics and Materials | Year: 2013

The operation of a mechanical machine may behave differently in various gravitational conditions. We compare the mechanical efficiency of a mass-spring system in three different gravitational conditions, namely hypergravity (2G), normal gravity (1G) and microgravity (0G) through parabolic flight. The simple system consisted of a mass load (18.92 g and 21.97 g) attached between two springs 6.91 N/m which make overall length 410 mm. The mechanical efficiency is justified by the decay of the oscillation amplitude of the attached load. Our result shows that the mechanical efficiency for the simple mass-spring system is better in lower gravitational condition. © (2013) Trans Tech Publications, Switzerland.


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.


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.


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.


Leng E.W.L.,National Space Agency of Malaysia ANGKASA | Azhar A.,National Space Agency of Malaysia ANGKASA | Salim H.,National Space Agency of Malaysia ANGKASA
26th Space Simulation Conference 2010 | Year: 2010

On 14th July 2009 at 0335 UTC, Malaysia created a history by being the first in the world to launch a satellite, RazakSAT™, to a Near-Equatorial Orbit (NEQO). After launching four communication satellites and two remote sensing satellites, Malaysia is ready to take a step further by setting up an "Assembly, Integration and Test (AIT) Centre" which will be used for assembly, integration as well as the launch and environmental testing for a satellite. This will be another achievement for Malaysia as it shall be the first facility to be setup in ASEAN region. The construction of the AIT facility began on 12th October 2009 and it is expected to be completed within a period of eighteen (18) months. There will be six equipments which will be housed in the AIT centre, all which are procured separately and from overseas. This facility has been designed by local engineers and architects, with the inputs and requirements from each equipment supplier. This centre will be the next stepping stone for the development of space program in Malaysia; therefore it is critical that the planning and managing of the AIT facility is in line with the objectives of the country's space program and that includes monitoring closely on the construction of the AIT building and the integration of equipments into the building so that the final result will be a completed and workable AIT facility that meets all the specifications and requirements specified.


Ishak A.N.,National University of Malaysia | Ishak A.N.,National Space Agency of Malaysia ANGKASA | Anwar R.,National University of Malaysia | Islam M.T.,National University of Malaysia | And 3 more authors.
International Conference on Space Science and Communication, IconSpace | Year: 2013

The dipole-based antenna has been employed in many radio telescope systems. By utilizing this type of antenna, the possibility to conduct all sky monitoring and high spatial resolution observation in the same time can be provided. In this research, a new dipole-based antenna system will be developed for 21cm line observation. The dipole-based antenna is optimized in terms of standing wave ratio (SWR), gain and beamwidth. Initial results show a good achievement on SWR level, down to 1.005. © 2013 IEEE.


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.


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.


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
International Conference on Space Science and Communication, IconSpace | Year: 2015

For succeed the early warning system development programme for space activity plan at Tawau, Sabah Malaysia, we studied the variation of rainfall and precipitation over convective system activity. We use five variables data such as the surface meteorological data (Pressure, Temperature and Relative Humidity), rainfall data, and precipitation. The surface meteorological data are taken from weather underground website, the rainfall data we obtain from rain gauge sensor Department of Irrigation and Drainage (DID) Malaysia, and also the precipitation data was obtained from NASA Satellite (Tropical Rainfall Measuring Mission). In this study, we attempt to estimate two variable targets (rainfall and precipitation) using Artificial Neural Network (ANN). The estimation was constructed as an alternative method to develop rainfall and precipitation model using surface meteorological data during convective system activity on summer monsoon over Tawau area. In this study, we processed surface meteorological, rainfall and precipitation data from 1 June 2011 to 31 August 2011. The Multilayer Perceptron (MLP) architecture and Levenberg Marquardt (LM) algorithms have been deployed in this study. We obtain the good result of estimation with one output target. The Root Mean Square Error (RMSE) value of rainfall and precipitation were 4.3540e-004 and 2.7834e-004 respectively and also Variance Accounted For (VAF) of rainfall and precipitation were 94.344% and 98.923% respectively during the training process. Testing results showed an error of 5.656% and 1.077% for precipitation and rainfall, respectively. However, we found the weakness of estimation model using three parameter inputs and two parameter output targets with the same structure. It means that for future work we suggest using 3 years data over convective system activity during summer monsoon is considered in the output target (rainfall and precipitation). © 2015 IEEE.


Salleh N.B.,National Space Agency of Malaysia ANGKASA | Ismail M.K.H.B.,National Space Agency of Malaysia ANGKASA
2010 International Conference on Computer Design and Applications, ICCDA 2010 | Year: 2010

Jupiter is the largest planet in the solar system and the fifth planet from the sun. In 1955, the Jupiter's signal had been noticed by radio lasers near Jupiter's magnetic poles. Since that, the Jupiter's activities had been studied and observed by the astronomer until now. The frequencies of Jupiter's most intense radio emissions extend from around 50 kHz up to 40 MHz. However, the observers usually listened on 20.1 Mhz because it is well above the ionospheres cut-off frequency and it is not where man made transmission frequencies would interfere. These emissions usually received with an amateur radio telescope. The Malaysia Space Agency had proposed the Radio Jupiter project to explore more about Jupiter's activities such as noise storms, flares, geomagnetic activity prediction and other scientific activities. The Radio Jupiter consist of three main components; antenna, receiver and amplifier, and recorder. This paper describes an overview of Radio Jupiter Project design and focus on designing a recorder which is a pc based software that uses as a little external hardware to record the Jupiter's signal. Finally, the data output from the system is presented and discussed. © 2010 IEEE.

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