Judul: Pengaruh Unsur Hara (N Dan P) Terhadap Biomassa Dan Struktur Komunitas Perifiton Studi Kasus Sungai Ciliwung
Abstrak: Research on the effect of nutrient to the structure of periphyton communities in Ciliwung river has been conducted from December 2010 to May 2011 at four stations; Gn. Mas, Kp. Pensiunan, Kp. Jogjogan, and Cibinong which reflected the of input of anthropogenic pollutant. This study aims to determine the relationship between nutrients (N and P) concentration and the structure changes of periphyton community in order to determine the ecological condition of Ciliwung River. The results of this study are expected to be useful to make a policy in the management of ecological disturbance of Ciliwung River based on pollutants loads and environmental changes due antropogenic activity. Water quality Ciliwung River was evaluated from the condition of habitats, pollution levels and the conditions of periphyton integrity to observed the actual condition of the aquatic environment. The results showed optimal habitat conditions was observed in Gn. Mas while other stations condition were marginal (Kp. Pensiunan, Kp. Jogjogan and Cibinong). Based on pollution level category, Gn. Mas and Kp. Pensiunan was unpolluted, while Kp. Jogjogan and Cibinong was slightly polluted and moderately polluted respectively. The results obtained 83 species of periphyton consisted of Bacillariophyceae (44 species), Chlorophyceae (20 species), Cyanophyceae (14 species), Rhodophyceae (1 species), Xantophyceae (2 species) and Dinophyceae (2 species). Based on the abundance of periphyton, PIBI score obtained was almost the same Gn. Mas (95,97), Kp. Pensiunan (84,65), Kp. Jogjogan (93,57) and Cibinong (83,83). CCA ordination of the results obtained a clear grouping among the research station. While the results from a combination of habitat conditions, the level of pollution and its PIBI value confirm that water conditions are still good.
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Judul: Struktur komunitas perifiton dan fitoplankton di bagian hulu sungai Ciliwung, Jawa Barat
Abstrak: Sungai Ciliwung sebagai salah satu bentuk perairan urnum banyak dimanfaatkan oleh masyarakat di sekitar sungai. Dari kegiatan-kegiatan tersebut perairan sungai akan mengalami degradasi baik secara halitas yaitu kirnia, fisika dan biologi maupun perubahan kuantitas. Penelitian ini dilakukan untuk mengetahui kondisi fisika kimia dan melihat struktur komunitas perifiton dan fitoplankton di bagian hulu sungai Ciliwung. Penelitian ini menggunakan data primer yang diperoleh dari hasil sampling pada bulan Juli dan Agustus 2005 dengan selang walctu dua minggu. Lokasi penelitian dibagi menjadi lima stasiun berdasarkan fungsi dan penggunaan tata guna lahan di sepanjang bagian hulu sungai Ciliwung. Parameter fisika kimia yang dianalisis adalah suhu, kecerahan, kedalaman, kekeruban, pH, arus, TSS, DO, BODj, nitrat, nitrit, ammonia, dan ortofosfat. Data perifiton dan fitoplankton yang dperoleh berupa komposisi dan kelimpahan. Analisis data yang dilakukan meliputi kelimpahan, keanekaragaman, keseragaman, dominansi, analisis kesamaan antar stasiun dengan menggunakan indeks Bray-Curtis dan indeks Canberra serta analisis komponen utama.
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Judul: Pricing of Lookback Options with Floating Strike Price Using The Monte Carlo Method
Abstrak: Opsi lookback adalah opsi yang payoff-nya bergantung pada harga saham terbesar atau harga saham terkecil yang dicapai selama masa berlaku opsi. Opsi lookback dikatakan dengan floating strike price jika nilai dari strike price sebesar harga saham pada saat jatuh tempo. Nilai hampiran opsi lookback ditentukan dengan metode Monte Carlo, sedangkan nilai eksak didapat dari nilai simulasi terbesar yang mampu dihitung oleh komputer. Berdasarkan hasil penghitungan, nilai galat relatif yang dihasilkan semakin kecil dengan semakin bertambah banyaknya simulasi yang dilakukan, sehingga metode Monte Carlo untuk menghitung harga opsi lookback dengan floating strike price konvergen ke nilai eksaknya., Lookback option is an option whose payoff depends on the maximum or minimum of the asset price reached during the option period. The lookback option is said to be a floating strike price if the value of the strike price is equal to the stock price at maturity. The value of the lookback option is determined by the Monte Carlo method, while the exact value is obtained from the largest simulation value that the computer can compute. Based on the calculation results, the resulting relative error value get smaller with the increasing number of simulations performed. Therefore, the Monte Carlo method to calculate the price of the lookback option with the floating strike price converges to the exact value.
Keyword: lookback option, floating strike price, Monte Carlo method, convergent