Judul: Processing data radar cuaca C-Band Doppler untuk curah hujan: studi kasus Jabodetabek
Abstrak: Rainfall is one of the most important element of the weather in a region. The study of rainfall has be done with a lot of method. One of them is by using the weather radar. The weather radar is classifeid in many group according to its frequency. This radar using the Doppler Concept in its process. This research is indicated to learn the processing of weather radar C-Band Doppler including its software to get the rainfall data in Jabodetabek region and to see the movement of rain fall region with weather radar data. The processing of this radar is in the computer with Linux Operating System with many software must be included, C, Fortran, Perl, and NetCDF. The processing needs some of script which can turn the primary data which is RAW format into the rain fall data (mm/hr). Cressman modification was used in the process, in order to turn the Raw format into reflectivity. The process needs the equivalence of Marshall-Palmer, in order to turn the reflectivity into CAPPI data format and Image CAPPI format. The result of this process is in text format, which is contain longitude, altitude, height, and rain fall. This rainfall value will be able to create many weather and climate infomation, such as rain fall region, floods, and more. In this research, the aplication of rainfall data is limited into the condition of rainfall region. The rain fall data will show the movement of the rain fall in a region. Jakarta, Bogor, Depok, Tangerang, and Bekasi were area case of study. According to result, the maximum of rainfall region is happening in the east and south of Jabodetabek, one of them is Bogor. Results data also showed the decrease in altitude, precipitation will be smaller.
Keyword: 

Judul: Model hidrologi terdistribusi hujan – limpasan berbasis integrasi data radar cuaca dan observasi hujan permukaan di Das Ciliwung
Abstrak: Rainfall data from C-Band Doppler Radar (CDR), surface rainfall station (AWS), and water level station (AWLR) from 14 Januari to 15 Februari 2010, were used in this research to obtain the relationship between radar reflectivity and rainfall intensity (rain rate) and to simulate the rainfall - runoff in Ciliwung River basin using distributed hydrologic simulation model. Data processing were focussed on observation data during the Intensive Observational Period (IOP) at the five sites, namely: Citeko, Bogor, Serpong, Serang, and Pramuka Island. The relationship between radar reflectivity and rainfall intensity establish the empirical constants a and b which was derived from Marshall – Palmer formula, the most suitable Z – R relation from the five rainfall stations is from Bogor site. The relationship obtained for Bogor site: Z = 0.046175 R2.814297 with correlation determination is 24,19%. River flow simulations were exercised based on Bogor site relationship for three rainfall intensity levels: light rainfall (1 – 5 mm/hour), heavy rainfall (10 – 20 mm/hour), and very heavy rainfall/extreme (>20 mm/hour), while flow simulation for medium rainfall (5 – 10 mm/jam) was not done because the results showed no much difference with light and heavy rainfall. River flow simulations during the period of 22 to 24 January 2010 for light rainfall condition (1 – 5 mm/hour) indicate the flow rate has no response because rainfall use almost all for evaporation, during 4 to 6 February 2010 for heavy rainfall condition (10 – 20 mm/hour) the highest flow rate is 844,002 m3/s, and the highest flow rate of 887,66 m3/s and 760,852 m3/s occurred on 9 to 11 February 2010, with two peak flows on February 10, 2010, for very heavy rainfall condition (> 20 mm/hour). Therefore the radar technology has good potential for near real time monitoring of extreme weather in Indonesia and prediction of related floods.
Keyword: 

Judul: Lignin Terlarut Asam dan Rasio Siringil-Guaiasil Lignin Pada Enam Jenis Kayu Eukaliptus
Abstrak: Lignin merupakan salah satu komponen kimia penyusun kayu selain dari selulosa, hemiselulosa dan ekstraktif. Sifat kimia lignin yang penting untuk diketahui diantaranya adalah kadar lignin dan reaktivitasnya. Pada penentuan kadar lignin dengan metode Klason, bisa diperoleh informasi kadar lignin Klason (lignin tidak larut asam) dan lignin terlarut asam. Sifat reaktivitas lignin dinyatakan dalam rasio siringil-guaiasil (rasio S/G) yang merupakan komposisi penyusun lignin. Berdasarkan penelitian terdahulu, lignin terlarut asam berkorelasi positif dengan kandungan metoksil. Sementara itu, kandungan metoksil juga berkorelasi positif dengan rasio siringil-guaiasil. Berdasarkan hal tersebut, proporsi siringil guaiasil diduga merupakan faktor penting dalam pembentukan lignin terlarut asam. Penelitian ini bertujuan untuk menentukan kadar lignin terlarut asam dan rasio siringil-guaiasil enam jenis kayu Eukaliptus dan korelasi antara keduanya, serta kemungkinan implikasinya terhadap sifat kayu, pengolahan dan penggunaannya sebagai bahan baku pulp. Penentuan kandungan lignin terlarut asam diukur dari filtrat penentuan lignin Klason. Lignin Klason merupakan fraksi padatan setelah penyaringan sedangkan lignin terlarut asam ditentukan dengan pengukuran penyerapan UV dari filtrat pada panjang gelombang 205 nm menggunakan koefisien absorpsi 110 lg-1 cm-1. Pengujian rasio siringil dan guaiasil penyusun molekul lignin dilakukan dengan metode Alkaline Nitrobenzene Oxidation seperti yang dilakukan oleh Chen (1992). Rasio siringil terhadap guaiasil dinyatakan sebagai perbandingan antara (siringaldehida+siringic acid)/(vanilin+vanilic acid). Hasil penelitian menunjukkan kadar lignin beragam antar jenis kayu yang berbeda dalam satu genus kayu Eukaliptus. Terdapat kecenderungan kadar lignin Klason yang lebih rendah diikuti oleh kadar lignin terlarut asam yang lebih tinggi. Lignin terlarut asam mempunyai korelasi yang kuat dengan rasio siringil-guaiasil. Lignin terlarut asam yang tinggi diperoleh dari lignin kayu yang memiliki rasio siringil guaiasil yang tinggi pula. Hubungan antara lignin terlarut asam dan rasio siringil-guaiasil dapat menjadi parameter penduga kemudahan suatu jenis kayu untuk didelignifikasi selama proses pulping.
Keyword: