Sains Malaysiana 43(3)(2014):
359–367
Pemodelan Hujan Denyut Segi Empat Neyman Scott (NSRP) Terbaik
di Semenanjung Malaysia
(The Best Neyman Scott Rectangular Pulse (NSRP)
Rainfall Modelling in Peninsular Malaysia)
RADO YENDRA1*, WAN ZAWIAH WAN ZIN2& ABDUL
AZIZ
JEMAIN2
1Department of Mathematics, Faculty of Science and Mathematics
Universitas Islam Negeri Sultan Syarif Kasim Riau, 28293
Pekanbaru, Riau, Indonesia
2School of Mathematical Sciences, Faculty of Science and Technology
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
Received: 7 February 2013/Accepted: 12 July 2013
ABSTRAK
Kajian ini bertujuan mendapatkan gabungan statistik
untuk pemodelan hujan kelompok berstokastik Denyut Segi Empat Neyman-Scott (NSRP)
yang mampu memberikan pemadanan terbaik bagi hujan di stesen hujan
Semenanjung Malaysia. Enam set gabungan statistik,
yang setiap setnya mengandungi gabungan statistik momen (1, 2 dan
3) dan kebarangkalian hujan dalam selang masa yang singkat (jam)
dan panjang (harian), serta empat taburan yang berbeza bagi kelebatan
sel hujan (Eksponen, Campuran Eksponen, Gamma dan Weibull) telah
dikaji. Penyelidikan telah dilakukan ke atas
sembilan stesen hujan yang mewakili rantau yang berbeza di Semenanjung
Malaysia. Hasil mendapati bahawa statistik
momen ke-3 (kepencongan) tidak memberikan sumbangan yang baik dalam
menjayakan model. Selang masa 1, 6 dan
24 jam didapati yang terbaik bagi statistik momen kedua (variasi)
bagi menjayakan model. Kajian ini juga mendapati bahawa taburan eksponen adalah yang terbaik
bagi pemodelan hujan NSRP di Semenanjung Malaysia.
Kata kunci: Eksponen; gamma; Neyman-Scott; statistik momen; Weibull
ABSTRACT
In this paper, a study to determine the best combination of
statistics for stochastic Neyman-Scott Rectangular Pulse (NSRP) rainfall modeling
had been carried out. Six sets of statistics, each of which contains a
combination of statistical moments (1, 2 and 3) and the probability of rain in
short time intervals (h) and long term (daily), as well as four different
distributions (Exponential, Exponential mixture, Gamma and Weibull) for rain
cell intensity were used and implemented on hourly rainfall data at nine
stations representing different regions of Peninsular Malaysia. The study shows
that the third moment statistics (skewness) did not give significant
contribution to the success of the model. On the other hand, the time interval
1, 6 and 24 h are the best for the second moment statistics (variation). This
study also found that the exponential model is the best distribution for
modeling NSRP rainfall in Peninsular Malaysia.
Keywords: Exponent; gamma; Neyman-Scott; statistics
moment; Weibull
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*Corresponding
author; email: yendra_75@yahoo. com.sg
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