Judul: Daya hambat Bacillus thuringiensis KAHN 15.39 terhadap cendawan patogen Curvularia affinis dan Colletotrichum gloeosporoides asal daun kelapa sawit
Abstrak: Some fungi caused disease on oil palm seedling so that it could be decrease seedling quality. Therefore, the aim of this research was to investigate activity of Bacillus thuringiensis KAHN 15.39 to inhibit pathogenic fungi Curvularia affinis and Colletotrichum gloeosporoides which were isolated from oil palm seedling. The bacteria ability to inhibit was examined with Leaf-pieces assays method. Bacteria culture medium was Nutrient Agar which was containing 1% Carboxy Methyl Celullose and medium for fungi used Potato Dextrose Agar added with 500 mg/L chloramphenicol. The results showed B. thuringiensis KAHN15.39 could inhibit Curvularia affinis which were the infestation areas 69 mm2 or biocontrol effectiveness 86% either, while to inhibit Colletotrichum gloeosporoides was the infestation areas 152 mm2 or biocontrol effectiveness by 45%. Inhibition of Bacillus thuringiensis KAHN15.39 against Curvularia affinis and Colletotrichum gloeosporoides have curative characteristic.
Keyword: Bogor Agricultural University (IPB), biocontrol effectiveness., Colletotrichum gloeosporoides, Curvularia affinis, Bacillus thuringiensis KAHN15.39, Oil palm

Judul: Pengujian Bacillus thuringiensis galur SAHA 12.08 sebagai pengendali pertumbuhan cendawan penyebab bercak daun kelapa sawit
Abstrak: Oil palm (Elaeis guineensis Jacq.) is one of major agriculture commodities in Indonesia. The disease caused by pathogenic fungi such as Curvularia affinis and Colletotrichum gloeosporoides could inhibit the growth of oil palm seedling plants. Cell wall, mycelia cells, stalks, and conidium of fungi that composed by chitin, can be degraded by chitinolytic bacteria through its ability to produce the chitinase enzyme. This research was aimed to study the ability of Bacillus thuringiensis strain SAHA 12.08 in inhibiting C. affinis and C. gloeosporoides that attacked oil palm leaf through in vitro experiment. Bacillus thuringiensis strain SAHA 12.08 showed inhibitor activity to pathogenic fungi using 24 hour and 12 hour bacteria culture. Result of inhibition test using Detached-Leaf Assays method showed that capability of Bacillus thuringiensis as biocontrol activity against C. affinis was 85% and 90%, and against C. gloeosporoides was 96% and 59%. Inhibition of the strain against C. affinis and C. gloeosporoides using in vitro test were 27,8% and 28,2 % respectively. Bacillus thuringiensis strain SAHA 12.08 had antagonistic activity at in vitro test using leaf of oil palm and showed biocontrol activity against C. affinis and C. gloeosporoides
Keyword: Bogor Agricultural University (IPB), oil palm, C. gloeosporoides, C. affinis, Chitinolytic bacteria

Judul: Penentuan Posisi Autonomous Underwater Vehicle (AUV) dengan Metode Dead Reckoning
Abstrak: AUV adalah wahana otonom bawah air yang memiliki berbagai sensor untuk akuisisi data. Alat ini dapat memudahkan survey bawah air karena bentuknya yang ringan. Misi AUV dibuat lalu disimpan ke dalam memori AUV. Penyelesaian misi memerlukan sistem navigasi yang akurat. GPS tidak bisa bekerja di dalam air sehingga dibutuhkan metode navigasi selain GPS. Dead reckoning adalah metode penentuan posisi dengan menghitung arah dan gerak AUV. Persamaan model kecepatan konstan digunakan untuk mengestimasi posisi pada saat t. Akurasi metode ini dipengaruhi banyak hal termasuk kesalahan sensor dan kondisi lingkungan. Misi dilakukan dalam 2 jalur berbeda sebanyak 3 kali. Jalur yang memiliki panjang lebih besar mempunyai kesalahan posisi yang tinggi. Ha ini disebabkan galat yang dihasilkan dead reckoning terakumulasi selama misi. Kesalahan tersebut dapat diatasi dengan memperhitungkan kondisi lingkungan pada program dead reckoning.
Keyword: AUV, DVL, Dead Reckoning, Navigasi