Judul: Aplikasi AGNPS untuk Menganalisis Kualitas Air Sungai Ciujung Kabupaten Serang, Banten
Abstrak: The water quality of river is affected by quality of water supply from the catchment area. The quality of water supply from catcment area associated with human activity. Human activities that affect the water quality also occured in Ciujung watershed in Banten Province. In this research, the decline of water quality from agricultural activities. Agricultural land in this watershed still large. The objective of this research is to analyze the water quality based on N, P, and COD parameters by using AGNPS. This application is a model that used to simulate and nutrient transport in catchment area. The methods that has been done is the gridding phase. The result showed that the water quality of Ciujung has descreased because of the organic matter. In the existing condition of the river, BOD, COD, DO, Cu and Cr parameters not contained the criteria of water quality class II. Based on the results of AGNPS simulation model, COD, N and P water quuality fits the criteria for class II based for agricultural activity
Keyword: Ciujung River, Water Quality, AGNPS

Judul: Kajian Peningkatan Kualitas Air Sungai Ciujung Berdasarkan Parameter Senyawa AOX (Adsorbable Organic Halides) dengan Model WASP (Water Quality Analysis Simulation Program) dan Model Dinamis
Abstrak: Ciujung River was the largest river in Banten Province with watershed area 1,935 km2 and 147 km length. The upstream of Ciujung River was located in Lebak Regency and the downstream was in Serang Regency. The river plays important role for Serang Regency for domestic, agricultural and industrial activities. At present, Ciujung River has become a national issue as a river that was polluted, decreased in discharge, river siltation due to the critical land in the upstream and industrial activity in the downstream that influenced the society’s health and social economy, especially in the downstream region.The river class and total maximum dayli loads (TMDLs) has not been determined by the national and regional government, so that the water river quality of Ciujung River was defined based on the Government Regulation No. 82/2001 concerning the management of water quality and water pollution control. However, adsorbable organic halides (AOX) parameter was not included in the regulation. AOX compound was a specific pollutant that toxic, hydrophobic, carcinogenic, persistent, and could be bio accumulated in fish body so it would pose a risk to human health. If there was no effort in controlling the pollution, it could be sustained and influenced the river function. The main objective of this research was to develop a model in controlling pollution in Ciujung River with three steps, i.e. (1) analyzing AOX compound in exist condition of Ciujung River, (2) determining the priority of pollution load controlling strategy in Ciujung River, and (3) formulating a model of pollution control in Ciujung River. The research was done by field survey, sample analysis directly in field and laboratory, questionnaire distribution, and in-depth interview with the expert. Water quality was analyzed with pollution index method; TMDLs was determined with water quality analysis simulation program (WASP). Priority of pollution load controlling strategy was analyzed with analytical hierarchy process (AHP) method. Model of Ciujung River water pollution control was developed with system approach using Powersim Studio 2005. The result showed that in existing condition, most parameter in several locations did not meet the criteria of class II water quality standard. DO, pH and nitrate content met the standard in all location, whereas BOD, COD, nitrite, phenol and AOX compound did not meet the standard.Status of Ciujung river water quality according to pollution index value without AOX compound, was in status of light to moderate polluted (IP 0.32 – 7.10). Whereas by considering the AOX parameter, Ciujung River was in status of light to severe polluted (IP 1.80 – 14.04). Potential pollution load that went into Ciujung River was come from non-point source, i.e. domestic, livestock, and agricultural waste and point source, i.e industry. The increase of pollution load potential that went into Ciujung River caused decrease of TMDLs. WASP simulation result showed that in minimum reliable discharge (1.9 m3/second), Ciujung River did not have TMDLs for class II river based on BOD (-3,470 kg/day) and AOX compound (-5 kg/day). The analysis result of priority strategy in controlling pollution in Ciujung River using AHP showed that three alternatives priorities need to be done to control the
Keyword: Bogor Agricultural University (IPB)

Judul: The Exploration of Discrete Logarithm over Finite Field GF(3m)
Abstrak: The security of many public~key algorithms is based on the problem of finding discrete logarithms. The generalized discrete logarithm problem is the following: given a finite cyclic group G of order n, a generator a of G, and an element fl E G, find the integer x, 0 ~ x ~ n - 1, such that 0: = fl. Algorithm for discrete logarithm problem focused on Menezes et al. (1997) that consist of exhaustive search algorithm, the baby-step giant-step algorithm, Pollard's rho algorithm, Pohlig-Hellman algorithm, and index-calculus algorithm. These algorithms are explorated to be used in discrete logarithm problem over finite field GF(3m ). The exploration also produces some algorithms, i.e. naif negative algorithm, baby-step mother-step algorithm, baby-step mother free-step algorithm, and baby-step free-step algorithm. All algorithms implemented using Maple 11. The Pohlig-Hellman and baby-step giant-step algorithms are efficient enough to be used in discrete logarithm problem over finite field GF(3m ) for m < 20.
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