Judul: Pollution Burden Analysis and Assimilation Capacity of Cidurian River Banten Province
Abstrak: The river has the ability to clean itself of the burden of pollution naturally which is known as the capacity of assimilation. Incoming load exceeds the capacity of assimilation would lead to a decrease in the quality of the river until the river functions decline. This research aims to analyze the water quality of Cidurian River, analyze the contribution of pollution loads entering River Cidurian, and knowing the assimilation capacity of the stream. Research results show that the water quality, starting from the upstream to downstream concentrations of BOD, TSS, COD and E. coli are likely to exceed the standard of quality. Contribution to the total burden of polluters from certain sources (point source) in DAS Cidurian 2,4 tons/month BOD, COD 4,3 tons/month, TSS 2,26 tons/month. The contribution burden of polluters undefinable (non point source) based on the analysis of land use from agricultural sector BOD 206,76 tons/month,TSS 24,13 ton/month, based on the analysis of the population of each sub DAS, domestic sector have 1.374 tons/month of BOD, COD 1.890 tons/month, TSS 1.305 tons/month and E.coli 1,02 E 16 tons/month. Total contribution burden of polluters undefinable (non point source) parameters BOD 1.580 tons/month, COD 1.890 tons/month, TSS 1.324 tons/month, more dominant compared to certain sourced (point source). Capacity of assimilation to the parameters of TSS 22.901,55 tons/month, BOD 2.347,83 tons/month, COD 24.208,33 tons/month, E.coli 424.629,90 tons/month. Overall value of assimilation capacity is smaller compared to the burden of pollution of the river, resulting in the organic matter pollution experienced TSS, BOD, COD and E.coli. The high contribution to the burden of domestic source of polluters and agriculture, as well as the capacity of assimilation to consider in an attempt to control water pollution.
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Judul: Water Quality and Pollution Load in Ciwidey Sub-Watershed
Abstrak: Sungai Ciwidey merupakan salah satu hulu Sungai Citarum yang berada di wilayah Kabupaten Bandung. Pertumbuhan penduduk dan penggunaan lahan di Sub-DAS Ciwidey menyebabkan perubahan pada parameter kualitas air Sungai Ciwidey, terutama di bagian hilirnya. Penelitian ini bertujuan menganalisis kualitas air, besarnya beban pencemaran, total beban pencemaran dan pengaruhnya terhadap kualitas air di Sub-DAS Ciwidey. Analisis hasil pemantauan kualitas air Sungai Ciwidey dibandingkan dengan baku mutu kelas I. Besarnya beban pencemaran dihitung menggunakan metode rapid assessment. Analisis kualitas air menunjukkan pencemaran bahan organik dengan indikasi tingginya nilai biological oxygen demand (BOD), chemical oxygen demand (COD), dan fecal coliform. Parameter lain yang melebihi baku mutu adalah total suspended solid (TSS), total fosfat, besi (Fe), mangan (Mn), seng (Zn), dan detergen total. Beban pencemaran terbesar berasal dari kegiatan industri. Total beban pencemaran sebesar BOD 70,9672 ton/bulan; COD 116,6503 ton/bulan; TSS 45,3445 ton/bulan; total nitrate (TN) 0,0387 ton/bulan; dan total phosphate (TP) 0,0172 ton/bulan. Konsentrasi beban pencemar terbesar terhadap debit air terjadi pada bulan Agustus dan terkecil pada bulan Januari., Ciwidey River is one of the headwaters of the Citarum River in Bandung Regency area. Population growth and land use in Ciwidey Sub-watershed have caused changes in the water quality parameters of the Ciwidey River, especially in the downstream part. This research aims to analyze water quality, the magnitude of the pollution load, total pollution load and its effect on water quality in the Ciwidey Sub-watershed. Analysis of the results of monitoring water quality of Ciwidey River compared to class I quality standards. Meanwhile, pollution load was calculated using rapid assessment method. Water quality analysis shows organic material pollution with indicate by high biological oxygen demand (BOD), chemical oxygen demand COD and fecal coliform values. Other parameters that exceed quality standards are total suspended solid (TSS), total phosphate, iron (Fe), manganese (Mn), zinc (Zn), and total detergent. The largest pollution load comes from industrial factories with BOD 70,9672 tons/month; COD 116,6503 tons/month; TSS 45,3445 tons/month; total nitrate (TN) 0,0387 tons/month; and total phosphate (TP) 0,0172 tons/month. The largest concentration of pollutant loads to water discharge occurs in August and the smallest in January.
Keyword: baku mutu, limbah, pencemaran air

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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