Judul: Pengaruh Dosis Pupuk Organik dan Hayati Terhadap Hasil Padi Sawah (Oryza sativa l.).
Abstrak: The research was carried out in the first growing season months of November 2011 - March 2012 in karawang, west java. The purpose of this research is to determine the rate effect of solid organic fertilizer (POP) and biological fertilizers (PH) on growth and yied at lowland rice (Oryza sativa L.). The treatments applied were: no fertilization (P0), with 100% dose of NPK (P1), 2 tons / ha POP (P2), 4 tons / ha POP (P3), 6 tons / ha POP (P4), 8 tons / ha POP (P5), 10 tons / ha POP (P6), 2l/ha Biological Fertilizer (PH) (P7), 2tons/ha POP + PH (P8), 4tons/ha POP + PH (P9), 6tons/ha POP + PH (P10), 8tons/ha POP + PH (P11), and 10tons/ha POP + PH (P12). Biofertilizer application of 2l/ha per application. 2tons/ha POP application only provides a decrease of the growth and yield lowland rice. Solid organic fertilizer (POP) at a dose of 4 tons/ha crop showed a lower growth compare with 100% NPK but it gives results in lowland rice better than 100% NPK dose. Biofertilizer application was not significantly different from giving 100% dose of NPK on of lowland rice, but a smaller yield than the 100% dose of NPK and other treatments. POP applications combined with biofertilizers can increase yields in lowland rice at growing season I, compared with the provision of 100% NPK dose only.
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Judul: Optimasi Dosis Pupuk Organik yang Diaplikasikan dengan Pupuk Hayati pada Budidaya Padi Organik
Abstrak: The research was conducted at Cibungur, Karawang Wetan, Karawang. Soil analysis carried out at the soil Laboratory, Department of Soil Science and Land Resources, agriculture faculty of IPB. The research was conducted from December 2012 to March 2013. The research design used was Randomized Plots Divided (Split Plot Randomized Block design). This research using a factorial design with two factors, namely bio-fertilizers and organic fertilizers. Data analysis using analysis of variance (F test), if real then by DMRT (Duncan Multiple Range Test) at the level of 5%. Treatment consisted of two biological fertilizer levels that is 2 l ha-1 application-1 and 0 l aplikasi-1 ha-1. Treatment of solid organic fertilizer consist of six levels, namely: 0 ton ha-1, 2 ton ha-1, 4 ton ha-1, 6 ton ha-1, 8 ton ha-1, and 10 ton ha-1 . The purpose of this study was to determine the effect of a combination of organic fertilizer with bio-fertilizers on organic rice farming. Applications POP 10 ton ha-1 resulted height plant, biomass plant, 1000 grain weight, GKP and GKG highest to all treatments. Application POP 8 and 10 ton ha-1 combined with bio-fertilizers can increase the yield of 6 and 10% grain yield, while treatment 2-6 ton ha-1 dont improve outcomes compared with control. POP dose 8-10 ton ha-1 increase grain yield around 10%.
Keyword: organic rice, organic fertilizers, bio-fertilizers

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf