cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kota adm. jakarta timur,
Dki jakarta
INDONESIA
Jurnal Sains Dirgantara
Published by Lembaga Penerbangan dan Antariksa Nasional
ISSN : -     EISSN : -     DOI : -
Core Subject : Education,
Education
Arjuna Subject : -
Articles 6 Documents
 1 
Search results for , issue "Vol 9, No 1 (2011)" : 6 Documents clear
PENGARUH SOLAR PROTON EVENT JANUARI 2005 TERHADAP PENIPISAN OZON STRATOSFER DI INDONESIA johan Muhamad; Novita Ambarsari
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (992.373 KB)

Abstract

Ozone data from Ozone Monitoring Instrument (OMI) and Microwave Limb Sounder (MLS) Aura satellite were used to investigate the impacts of the very intense Solar Proton Events (SPE) 15-25 January 2005 on the stratospheric ozone in Indonesia. From the ozone vertical profiles along the SPEs period, the decreasing of ozone concentration was observed after the peak of the SPEs. This ozone decrease was associated with the increase of NO2 and HO2 concentration which was produced due to the ionization by the energetic protons. The ozone decrease was also identified by analyzing the spatial column amount ozone in Indonesia. The ozone decrease after the SPEs was about 8 percent from the average of daily column amount ozone before the SPEs. The very high energetic protons from the SPEs were suspected to be responsible for the possibility of the proton precipitation into the low latitude regions. Keywords: Solar Proton Event, Stratospheric ozone depletion, Low latitude proton precipitation 
PENENTUAN ONSET MONSUN DI WILAYAH INDO-AUSTRALIA BERDASARKAN LOMPATAN ITCZ Didi Satiadi; Ibnu Fathrio
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (539.108 KB)

Abstract

Inter-Tropical Convergence Zone (ITCZ) is one of the factors affecting weather and climate in the Indonesia Maritime-Continent Region together with El-Niño Southern Oscillation (ENSO), Indian Ocean Dipole Mode (IODM), Madden Julian Oscillation (MJO), Tropical Cyclone (TC), and Monsoon. ITCZ influence weather and climate in the Indonesia region. Therefore, monitoring and understanding ITCZ behaviour become important as an alternative method to predict variability, anomaly, and extreme atmospheric conditions in Indonesia region. Research has been conducted to study the behaviour of ITCZ in the Indonesia maritime-continent region using Multi-Functional Transport Satellite (MTSAT) data from year 2006 to 2009. Identification of ITCZ and its movement was carried out based on minimum cloud top temperature observed by MTSAT satellite. Meridional movement of ITCZ were then compared to the Indo-Australia Monsoon Indices and rainfall from Tropical Rainfall Measuring Mission (TRMM) satellite. The results showed that ITCZ positions tend to exist at certain locations and experienced jumps to mid-latitude during seasonal change to dry and wet seasons. The results can be used to predict monsoon onset in the Indo-Australia region based on ITCZ jumps, and also to verify rainfall prediction models which in turn can be applied to hydrological models, environtmental models, and rainfall-related disaster early warning systems. Keywords: ITCZ, Monsoon, Onset, Satellite, Indonesia
PENGARUH IONOSFER PADA AKURASI PENENTUAN POSISI ABSOLUT DENGAN GPS SINGLE FREQUENCY PADA SAAT TERJADI BADAI MATAHARI Buldan Muslim
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (871.818 KB)

Abstract

The effect of the ionosphere on the propagation of signals emitted from GPS satellites at an altitude of about 20,000 km is in the form of code delay or carrier advance of the signal propagation time which depends on the Total Electron Content (TEC) and the GPS signals frequency. Coronal Mass Ejections (CMEs) occurred during October 28 and 29, 2003 solar storms have caused ionosphere disturbances called ionospheric storms. The ionospheric storms have degraded the accuration of single frequency GPS absolute positioning to more than 400%. Mitigation of ionospheric storms effect on the single frequency GPS absolute positioning by using Klobuchar model can not produce a significant increase in accuracy. Hence during the ionospheric storms, the regional ionospheric TEC model is needed for ionospheric correction of single frequency GPS absolute point positioning. Keywords: Solar storm, Ionosphere, Radio wave, Propagation, Positioning, Accuration
KLASTER CURAH HUJAN TRMM RATA-RATA 3 JAM-AN DAN HUBUNGANNYA DENGAN FENOMENA ATMOSFER Ina Juaeni; Bambang Siswanto; - Nurzaman; - Martono; Farid Lasmono
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1085.903 KB)

Abstract

Three hourly Tropical Rainfall Measuring Mission (TRMM) rainfall data availability provides an opportunity to study more deeply in short time atmospheric process, as is presented in this paper. Arithmatic mean value of rainfall is used to eliminate micro and local factors. Clustering with annual average data show the number of clusters varies from 6 to 14. The number of the smallest cluster of 6 occurred in 2004, while the number of the highest clusters found in 2010. Identify the relationship of 3-hourly rainfall clusters with an atmospheric phenomenon carried out by evaluating the correlation between the number of clusters with Sea Surface Temperature (SST) anomalies in the Pacific and Indian oceans. The results showed clusters number unrelated to SST anomaly in Indian ocean and linearly related to SST anomaly in the Pacific ocean when SST anomalies in the ocean are changing the three hourly accumulative rainfall. Key words:Three hourly, Rainfall, Cluster, SST anomaly
HOLT-WINTERS DALAM PREDIKSI ANOMALI OLR Eddy Hermawan
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (301.787 KB)

Abstract

One of the pivotal study when analyzing the impact of the Madden-Julian Oscillation (MJO) phenomenon on rainfall anomalies in the Western part of Indonesia region is knowing the characteristics and the prediction of Outgoing Longwave Radiation (OLR) as the main parameter. This paper, focused to develop a predictive model OLR using the Box-Jenkins (ARIMA) method, which compared by the Holt-Winters method. This analysis focused on the average five days (pentad) OLR data in the Western part of Indonesia region, precisely at the position of 120oE for period of January 2007 to December 2009. Based on the comparison of the MSE (Mean Squares of Errors), and the MAPE (Mean Absolute Percentage Error) obtained from the Box-Jenkins (ARIMA) and Holt-Winters methods can be concluded that appropriate to predict the value of pentad OLR data on the position 120oE is the Box-Jenkins (ARIMA) method, because it has smaller value of MSE and MAPE comparing with the Holt-Winters method. Box-Jenkins model is the model ARIMA (1.0.1)(0.1.1)9 according to the results of significance analysis, autocorrelation in the residuals (white noise), also normality of residuals, where the process is repeated until model is really suitable and best meet the assumptions of model selection. The models can be assessed by the signal tracking value at each forecasting model. This assessment showed two of models in accepted boundary value, i.e ±5. This shows forecasting model can still be used to predict the 4 periods of the OLR pentad anomaly. Keywords: Box-Jenkins (ARIMA), Holt-Winters, OLR, and Prediction Model ABSTRAK Salah satu kajian penting ketika menganalisis dampak dari fenomena Madden-
STOCHASTIC PROCESS IN THE TIME SERIES MODEL OF PACIFIC DECADAL OSCILLATION (PDO) Sandro Wellyanto Lubis
Jurnal Sains Dirgantara Vol 9, No 1 (2011)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1080.555 KB)

Abstract

Pacific Decadal Oscillation (PDO) is long-lived El Niño-like pattern of Pacific climate variability generated by coupled ocean-atmosphere interaction in the Northern Pacific Ocean. The best way to acquire a signal of PDO evidence is by determining the index of PDO. In this study, the PDO indexes are accurately modeled with time series methods through exponential smoothing analysis (Single and Holts Double exponential smoothing model) and Box-Jenkins analysis (ARIMA {1,1,1}, {2,1,1}. {3,1,1} and {4,1,1}). Nicholas’s PDO Model (ARMA 9, 7) is also considered as comparative model in order to obtain the level of the reliability models that have been produced. The best selected prediction model that close to the real PDO index is ARIMA (2,1,1) Zt = 1.574* Zt-1 -0.427* Zt-2 -0.147* Zt-3 -0.976* at-1 which means the forecast of PDO in the future depending on three months earlier data and a month earlier error of PDO index. Mean absolute error (MAE) of this model is 0.5283 and with root mean square error (RMSE) 0.6661. The predicted and observed PDO indexes are significantly correlated with r =0.76. Keywords: PDO, Box-Jenkins analysis, Exponential smoothing analysis 

Page 1 of 1 | Total Record : 6

 1 

Filter by Year

2011 2011


Reset
Filter By Issues
All Issue Vol 19, No 2 (2022) Vol 19, No 1 (2022) Vol 18, No 2 (2021) Vol 17, No 1 (2020): Vol. 17 No. 1 Desember 2019 Vol 18, No 1 (2020) Vol 17, No 2 (2020) Vol 17, No 1 (2019) Vol 16, No 2 (2019) Vol 16, No 1 (2018) Vol 15, No 2 (2018) Vol 15, No 1 (2017) Vol 14, No 2 (2017) Vol 14, No 2 (2016) Vol 13, No 2 (2016) Vol 13, No 1 (2015) Vol 12, No 2 (2015) Vol 12, No 1 (2014) Vol 11, No 2 (2014) Vol 11, No 1 (2013) Vol 10, No 2 (2013) Vol 10, No 1 (2012) Vol 9, No 2 (2012) Vol 9, No 1 (2011) Vol 8, No 2 (2011) Vol 8, No 1 (2010) Vol 7, No 2 (2010) Vol 7, No 1 (2009) Vol 6, No 2 (2009) Vol 6, No 1 (2008) Vol 5, No 2 (2008) Vol 5, No.1 Desember (2007) Vol 4, No 2 (2007) Vol 4, No.1 Desember (2006) Vol 3, No.2 Juni (2006) Vol 3, No.1 Desember (2005) Vol 2, No.2 Juni (2005) Vol 2, No.1 Desember (2004) More Issue