Judul: Pemodelan Stokastik Pertumbuhan Penduduk di Kota Rembang dengan Mempertimbangkan Proses Kelahiran, Kematian, dan Migrasi
Abstrak: The Population growth can be determined using birth and death rates and also the factor of migration. Both birth and death proceses are considered within Poisson process. An increase of population level would decrease the land residence, the number of homes, and the job opportunities. Therefore, we need stochastic models to estimate the population level in the Rembang city, Central Java province. This study is to draw up a stochastic population growth model through birth, death and migration process to predict the level of population. The data are processed using the trend analysis and the merger methods. The result of stochastic modeling shows that the level of population in the city of Rembang in 2013 are 603784, and in the following year was 610895.
Keyword: Bogor Agricultural University (IPB), Poisson process., population growth, stochastic model, trend analysis

Judul: Models of Bogor Population Growth with Stochastic Approach
Abstrak: Pertumbuhan penduduk dapat dihitung menggunakan angka kelahiran, kematian, dan migrasi. Pertumbuhan penduduk mengakibatkan meningkatnya keperluan tempat tinggal dan permintaan lapangan pekerjaan. Oleh karena itu diperlukan model stokastik untuk memperkirakan tingkat penduduk di Kota Bogor, Jawa Barat. Penelitian ini bertujuan untuk menyusun model pertumbuhan penduduk Kota Bogor dengan pendekatan stokastik melalui proses kelahiran, kematian, dan migrasi sehingga dapat meramalkan jumlah penduduk yang akan datang. Hasil aplikasi model menunjukkan bahwa proyeksi jumlah penduduk Kota Bogor tahun 2020 sampai dengan 2025 berturut-turut sebesar 1126645, 1141856, 1157273, 1172897, 1188733, 1204782 jiwa dengan masing-masing selang kepercayaan 95% berkisar antara [1126644, 1126646], [1141855, 1141858], [1157271, 1157274], [1172895, 1172899], [11887331, 11887335], dan [1204780, 1204785]., The population growth causing the increase of housing need and job vacancy demands. Because of this, stochastic model is needed to predict the population growth in Bogor City, West Java. The intend of this research is to arrange models of Bogor population growth with stochastic approach through birth, death, and migration process in order to be able to predict population number in the future. The results of model application show that the projected population of Bogor City in 2020 to 2025 are respectively 1126645, 1141856, 1157273, 1172897, 1188733, 1204782 people with each of 95% confidence interval ranging from [1126644, 1126646], [1141855, 1141858], [1157271, 1157274], [1172895, 1172899], [11887331, 11887335], and [1204780, 1204785].
Keyword: Bogor City, population growth, stochastic modeling

Judul: Elektrodeposisi Film Tipis Semikonduktor Cu2ZnSnS4 (CZTS) pada Substrat Kaca ITO
Abstrak: Semiconductor Cu2ZnSnS4 (CZTS) thin film that can be used as absorber layers on solar cell module was made via electrodeposition method. CZTS thin film was electrodeposited on the surface of a silicate glass coated with a thin layer of indium tin oxide (ITO). Deposition process was done using potentiostatic mode at room temperature with a potential of 1.05 V for 30, 45, and 60 minutes, followed with annealing the film at 2 different temperatures, 500 ºC using furnace and 180 ºC using hot plate, both treatments for 45 minutes in N2/H2S atmosphere. The X-ray difractograms were analyzed using Match 2 program and showed that the CZTS thin films had kesterit crystalline structure, with a low percentage of CZTS phase. The thin film also contained secondary phases such as Cu2S, ZnS, and SnS. The obtained CZTS thin films had a thickness between 1.039 and 1.676 μm. Absorption study showed that the band gap energy of CZTS thin films which was annealed using furnace ranged from 1.50 to 1.52 eV, whereas that annealed using the hot plate was not observed. The band gap energy value showed that CZTS thin films can be used as sunlight absorber layers on solar cell. The formation of CZTS crystal film on this investigation was effectively performed using furnace annealing process at a temperature of 500 ºC with deposition time of 45 minutes.
Keyword: Thin film, Electrodeposition, Cu2ZnSnS4