Judul: Penentuan Ambang Batas Nilai Ekstrem dan Pendugaan Parameter pada Sebaran Pareto Terampat
Abstrak: Teorema Nilai Ekstrem adalah metode yang secara khusus membahas kejadian-kejadian ekstrem. Salah satu cara dalam penentuan nilai ekstrem, diantaranya menggunakan Mean Excess Plot (MEP), yaitu dengan menentukan nilai ambang batas u kejadian ekstrem berdasarkan sebaran Pareto Terampat (Generalized Pareto Distribution, GPD). Pemilihan ambang batas dilakukan berdasarkan linieritas MEP, walaupun umumnya tidak mudah dan sedikit subjektif. Pada penelitian ini untuk menduga nilai parameter bentuk dari sebaran GPD yang dihasilkan MEP digunakan plot Hill, plot Pickands, dan slope atau koefisien kemiringan plot Q-Q. Plot penduga parameter dipilih ketika pola terlihat stabil. Data simulasi yang dibangkitkan dengan mengikuti sebaran GPD menunjukkan bahwa metode MLE dan Pickands lebih baik dalam pendugaan parameter bentuk dibandingkan dengan Hill dan plot Q-Q berdasarkan nilai MAPE yang kecil dan hasil dugaan parameter bentuk yang semakin baik jika nilai parameter bentuk mendekati satu. Untuk data riil, nilai ambang terbaik pada data curah hujan bulanan di stasiun curah hujan Indramayu adalah 340 mm, yang dipilih berdasarkan dugaan parameter bentuk yang konsisten dengan 0< <1.
Keyword: EVT, GPD, MEP

Judul: Pendugaan Nilai Ekstrim Menggunakan Sebaran Champemowne Termodifikasi, Sebaran Pareto Terampat, dan Nilai Gabungan (Studi Kasus Curah Hujan Harian Darmaga Bogor)
Abstrak: Extreme rainfall can give a negative affect for human activity. Negative effect of production failure in agriculture and plantations can be anticipated by extreme rainfall estimation that may occur in the future. The aims of this study is to compare the extreme rainfall estimation using the modified Champernowne distribution and generalized Pareto distribution (GPD), and determine the optimum weights of combined extereme value estimation. Modified Champernowne distribution patern has convergence to the GPD that the distribution function consists of three parameters that describe the data center, the diversity, and characteristics of the end of the distribution. While GPD consists of two parameters that describe the diversity and characteristics of the end of the distribution (heavy tail/tail light). The data used are daily rainfall data in Darmaga Bogor Station during the period 1985-June 2011 were obtained from the Indonesian Agency for Meteorology Climatology and Geophysics. GPD estimation tends to over estimate while modified Champernowne distribution estimation tends to under estimate. The combine of the estimated value by weighted produces more accurate extreme value estimation. Forecasting results for 1, 2, and 3 month ahead show that the best prediction based on modified Champernowne distribution, while forecasting results for 6 and 9 month ahead is very well predicted by GPD and combined value.
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Judul: Produksi Kromium Organik dari Fungi serta Peranannya bagi  Aktivitas Fermentasi Rumen
Abstrak: Organic chromium has higher availability than inorganic chromium sources. One of organic Cr h w n is Cr inoorporated to protein fungi. Info~tion about the best fungi or m i ~ s usmed in organic Cr production is still limited Tbus, this expabent was comlwted to study about organic chmium production using cliff- kind of fungi as its carrier, and and evaluate its effects on rumen' fermentation activity. The eqmhtnt consist of two steps. Orgatllc Cr production was c o n d d with a 4x3 factwid Compldy Randomized Design with 3 replication Four fungi used as courier in organic Cr production as first factor were S a c ~ ~ceerevsisia e, AspergilIta o w e , M izopk 0- a d" mgi tape". Second factor was level of chromium addition (500, 1000 dan 1500 mg/kg). Effects of organic chcmium supp1em4on on rumen fermentation activity measured with in vim technique, using Raudomhd Blmk Design with 13 merits and 3 replication. Addition of 1000 rn@g Cr gave the highest Cr incorpoxation to fungi protein (484 mgi'kg) and Cr hcqmmtion efficiency (21,06%). Best fungi used as carrier in organic Cr producbon was Rhizoptnrs oryzae which gave the highest Cr incorporation (488 m@g) and inmpmtion efficiency (24,Ph). Supplementation of I mflg organic Cr increased dry matter and organic matter digestibility in a h kid of fungi used as carrier. It tends to incmsad NF& and total VFA w o n . Partial VFA profile s h o d iacreased propionate p d u c t i g which d e a a d methane production atmd increased hexose convertion efficiency in d lmttmats. Suggested organic Cr wed was 1 m@gg Each h g i used as carrier in o ~ c C r a s u t t e d ~ e f f e c t s m n u n e n f ~ ~ ~ a c t i v i t y , b ~ ~ ~ no m e result showed. It could be concluded that wether Sawhmyces cerevt;piae, AsprgiZIus mywe, MRophus o w e or "IT@ tape" could be US& as carrier in organic Cr pdwt~on
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