Judul: Evaluasi Daerah Rawan Banjir Dengan Menggunakan Model HECRAS Di Sub DAS Dayeuhkolot Bandung
Abstrak: Banjir merupakan genangan yang disebabkan oleh volume air yang mengalir pada suatu sungai ataupun saluran drainase yang melebihi kapasitasnya. Hal ini terjadi karena pemanfaatan daerah aliran sungai (DAS) yang berlebihan sehingga banjir terjadi di musim hujan, kekeringan di musim kemarau, dan penurunan nilai debit air sungai. Penelitian ini mengevaluasi daerah rawan banjir di Sub DAS Dayeuhkolot, Kecamatan Dayeuhkolot, Kabupaten Bandung, dengan menggunakan Sistem Informasi Geografis (SIG) dan model hidrologi HEC-RAS pada aliran mantap (steady flow). Metodologi penelitian meliputi empat langkah yaitu, river centerline, river banks, flowpath, dan cross section. Hasil analisis menunjukan bahwa perubahan tutupan lahan akibat meningkatnya kepadatan pemukiman di sekitar Sub DAS, menyebabkan banjir di Kecamatan Dayeuhkolot dengan nilai debit maksimum yang digunakan yaitu 219,75 m³/s, nilai koefisien aliran 0,65, nilai intensitas hujan maksimum 28,2 mm/hari, nilai luas daerah aliran sungai 1.035,8 km2, nilai mannings 0,02, dan nilai Froude 0,6 (Sub-Critical). Luara model berupa peta menunjukkan bahwa beberapa titik banjir yang meluap dari daerah alirannya mengenai jalanan serta wilayah industri. Hal tersebut disebabkan oleh lengkungan pada DAS, dimana kecepatan aliran mempengaruhi sebaran besarnya banjir yang terjadi. Hasil validasi yang dilakukan menggunakan metode kappa koefisien dengan tingkat akurasi sebesar 64%. Model hidrologi HEC-RAS mampu digunakan untuk memodelkan sebaran daerah rawan banjir di lokasi kajian.
Keyword: Flood, Watershed, Dayeuhkolot, HEC-RAS

Judul: Estimasi Sebaran Daerah Rawan Banjir Menggunakan Model HEC-RAS dan Kerugian Masyarakat di Wilayah Sub-DAS Citarik
Abstrak: Flood events in Upper Citarum watershed, especially in Citarik Subwatershed has increased sharply and it caused high enough economic loss. HECRAS model can be used to solve flood problem. Therefore, it is necessary to study Citarik Sub-watershed to identify the flood prone areas using HEC-RAS model and compute the economic loss in residential building sector in this region. Energy equation was used to compute steady flow analysis in HEC-RAS program. Flood prone areas dominantly occurred in low land areas, i.e. Rancaekek Kulon, Wangisagara, and Padamukti village that consist landuse land cover of rural, paddy,and secondary forest with low enough model accuracy. Rancaekek Kulon had the largest flooded areas which had high enough economic loss in minimum and maximum flood event.
Keyword: Bogor Agricultural University (IPB), economic loss., flood prone area, HEC-RAS Model

Judul: Apatite Growth Optimation on Chicken Mucouse by Fourier Transform Infrared (FTIR) Characterization
Abstrak: Some experiment had been conducted to grow apatite from supersaturated solution of calcium phosphate ions on chicken mucouse. The calcium and phosphate ions were originated from Ca(NO3)2 and (NH4)2HPO4. Carbonate ions from (NH4)2CO3 was also used as starting solution. Experiment was carried out within about 5 hours at temperature 370 C and pH 7. Value of Ca+ : PO4 3- was 1.67, while molar ratio of CO3 2- : PO4 3- was 0.5 : 1. Molarity of molar ratio CO3 2- : PO4 3- variated approximately 0.15 : 0.30, 0.51 : 1.02, and 0.90 : 1.80. Mass of mucouse powder was constant 0.75 gram. The analysis result of Fourier Transform Infrared (FTIR) showed that the precipitation was apatite carbonate type A and B. In these experiment it was found out that the mucouse reduce the crystallinity of apatite precipitant, and the growth of apatite crystal was optimum at solution with molar ratio CO3 2- : PO4 3- about 0.15 : 0.30.
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