Judul: Analisis Curah Hujan Diurnal Menggunakan Data Satelit TRMM
Abstrak: Diurnal rainfall observation using TRMM data that had been conducted in Indonesia on 2002 and 2006 showed that diurnal rainfall variation existence where evening rain (12LT-21LT) is higher than morning rain (00LT-09LT) on a land area. Morning rain on sea tends to be higher than the evening rain. In addition, observation also proved that there is rainfall movement from inland to sea area. Rainfall devolves into inland area which heaten up faster during the day and return to sea area during the night. Analysis of diurnal rainfall variation on Bogor, Jakarta, Jambi, Pontianak and Gorontalo during 2002 indicated all different regional rainfall peak from each other. Furthermore, Jakarta flood case observation during January 27th 2002 until February 1st 2002 period reffered that flood events on Jakarta were caused by high rainfall intensity on January 27 th 2002 at 18LT observed by TRMM data and GMS-5 data.
Keyword: Bogor Agricultural University (IPB), TRMM, Jakarta, GMS-5, flood, diurnal rainfall

Judul: Evaluasi Curah Hujan GSMaP dan TRMM TMPA dengan Curah Hujan Permukaan Wilayah Jakarta – Bogor
Abstrak: Global Satellite Mapping of Precipitation (GSMaP) and Tropical Rainfall Measuring Mission Multi-Satellite Precipitation Analysis (TRMM TMPA) are global measured precipitation projects using satellite combination (blended) technique of infrared sensor and microwave sensor. This research having purpose to evaluate GSMaP and TRMM data with Surface rainfall data in various topographies (beach, level-land, mountainous region, and The whole area) and temporal variation (daily, 10days, and monthly) in Jakarta-Bogor area. The evaluation is done using visual and statistical comparison method (correlation coefficient, MAE, RMSE, and Mann-Whitney Test). The evaluation result of daily and 10days of GSMaP in all area studies showing a pattern didn’t follow the Surface rainfall (r<0.20), while TRMM daily rainfall data in beach area and The whole having r>0.60 and the Mann-Whitney test shows TRMM doesn’t have significant difference with surface rainfall data. 10days TRMM rainfall in all region, except mountainous region, shows TRMM rainfall can follow surface rainfall pattern (r>0.77). Monthly GSMaP data comparison to surface rainfall showing correlation more than 0.60 on beach and land area can be applied, by using correction equation, because GSMaP rainfall data always lower than surface data. The monthly TRMM rainfall data can be applied in all studies area because the pattern is suitable to surface rainfall data (maximum correlation is 0.98). Error identification shows that there is warm rain and high variation on land surface emission especially in mountainous area causing either GSMaP and TRMM cannot follow the surface rainfall data. GSMaP correction equation in beach region, shows the parameter that affect error are surface temperature and specific humidity in 850mb, while at region II, III, and The Whole there is no local parameter which has influence. TRMM correction equation in region III(mountainous area), shows local parameter which has an influence to accurate of this TRMM is surface pressure, wind 850mb, interaction of meridional wind and surface slope, air temperature 850mb, soil humidity in 10-200cm, and skin temperature.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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