Judul: Analisis Frekuensi Banjir dengan Empat Sebaran Statistik pada Tiga Stasiun Sungai Ciliwung
Abstrak: Kejadian banjir di Jakarta dari tahun 1981-2014 semakin sering terjadi. Data Badan Nasional Penanggulangan Bencana (BNPB) menunjukkan bahwa banjir terbesar di Jakarta terjadi pada tahun 1984, 1996, 2002, 2007, dan 2013. Berbagai kegiatan pengendalian banjir telah banyak dilakukan dengan membuat beberapa bangunan pengendali banjir. Pembuatan bangunan pengendali banjir ini membutuhkan perhitungan mengenai hujan rancangan dan debit puncak dalam berbagai periode ulang untuk merencanakan ketahanan dan umur bangunan terhadap curah hujan dan debit yang terjadi. Perhitungan hujan dan debit puncak menggunakan analisis frekuensi berdasarkan data curah hujan maksimum 1-harian, 3-harian, dan 5-harian di Stasiun Katulampa, Stasiun Depok, dan Stasiun Tanjung Priok. Hujan rancangan dihitung menggunakan empat sebaran statistik, yaitu Sebaran Normal, Log Normal, Log Pearson Tipe III, dan Gumbel. Hasil curah hujan rancangan 1-harian, 3-harian, dan 5-harian masing-masing berkisar antara 100-250 mm, 200-350 mm, dan 250-400 mm. Curah hujan rancangan di Stasiun Tanjung Priok nilainya paling besar, sedangkan curah hujan rancangan di Stasiun Katulampa paling kecil nilainya. Debit puncak dihitung menggunakan Metode Rasional dengan mempertimbangkan luas DAS dan penggunaan lahan DAS Ciliwung. Debit puncak dengan periode ulang 100 tahun di Katulampa yaitu 264.2 m³/detik, di Depok sebesar 684.32 m³/detik, dan Manggarai sebesar 962.826 m³/detik. Debit puncak di Manggarai paling besar dibandingkan Stasiun Katulampa dan Depok, karena stasiun Manggarai berada di hilir DAS Ciliwung, sehingga jumlah debit puncak merupakan hasil akumulasi debit dari hulu, tengah, dan hilir DAS Ciliwung….
Keyword: Ciliwung Watershed, Design Rainfall, Flood, Gumbel Distribution, Peak Discharge, Geophysics and Meteorology, Curah hujan, Hujan rancangan, Hidrologi, DAS

Judul: Analisis Jaringan Sungai Ciliwung Hulu untuk Menentukan Hidrograf Banjir
Abstrak: Hydrograph is a graphical representation of flow with time. Hydrograph shape is determined by the rainfall input and morphometry of the watershed. Upper Ciliwung watershed contributes greatly to the floods that hit Jakarta. This study aimed to determine the characteristics of the Upper Ciliwung river networks and analyze the flood hydrograph pattern formed by the river network density. Determination of the characteristics of stream network is based on SRTM DEM 90 m x 90 m, and it is obtained that the Upper Ciliwung river has four Strahler river order with length ratio (RL) and branching ratio (Rb) that were different for each river order . Flood hydrograph was calculated using geomorphology convolution method and the simulated discharges were compared to observed discharges recorded at the Katulampa station for two rainfall events on January 16, 2013 and March 4, 2013. Based on the values of Nash-Sutcliffe coefficient obtained from the comparison of simulated discharge and observed discharges that were 0.72 for January 16, 2013 flood and 0.66 for March 4, 2013 flood, it is concluded that flood could be determined using geomorphology convolution method based on the river network density from SRTM DEM data.
Keyword: SRTM DEM data, River network characteristics, Geomorphology convolution method

Judul: Synthesis of Apatite - Chitosan Composite Using Duck Eggshell and Chitosan with Temperature and pH Control
Abstrak: Composite of apatite-chitosan was prepared by using chitosan as polymer matrix. Calcium phosphate was prepared from CaO and (NH4)2HPO4, which the ratio Ca : P had to be 1.67. Chitosan is produced by deacetilase from biopolymer chitin. Duck eggshell (95% CaCO3) as starting material was converted to be calcium oxide (CaO) through calcinations with temperature 1000oC for 5 hours. In-situ and ex-situ methods were prepared from apatite and chitosan (dissolved with acetate acid 2%). Calcium phosphate prepared for bone implantation, but it is too fragile and brittle to be implant into the body. So addition of chitosan can decrease crystalinity and increase mechanic characteristic (tougher). Composite apatite-chitosan was resulted by fast precipitation. Fast precipitation was held in a breaker glass with nitrogen atmosphere, under controlled temperature at 37oC and pH 7, in order to increase amount of hydroxyapatite. Precipitation with CaO which was dropped by (NH4)2HPO4. Hydroxyapatite and chitosan were appearing at samples with in-situ and ex-situ methods which indicating by peak matching of XRD (closed lattice parameter, crystal size), overlapping at FTIR spectra and supporting by SEM picture (homogenous and agglomerated particle). However, it still needs further research to examine biocompatibility osteoconductive degree of sample by in-vivo and in-vitro test.
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