Judul: Optimasi Pupuk Dolomit pada Tanaman Kelapa Sawit (Elaeis guineensis Jacq.) Belum Menghasilkan Umur Satu Tahun
Abstrak: This research aims to determine the optimum rate of fertilizer dolomit on oil palm plant aged one year. This experiment was conducted at the IPB-Cargill Palm Oil Teaching Farm, Jonggol, Bogor from March 2013 to March 2014. The design used is randomized complete block design with three replications and one factor was dolomit fertilizer rates i.e. 0, 200, 400, and 600 g plant-1. Each experimental unit consisted of 5 plants, so the number of samples is 60 crop plants. Dolomit fertilizer affected vegetative and physiology variables. Based on the plant height the rates of dolomit fertilizer recommendations for plant oil aged one year is 306.4 g dolomit plant-1.
Keyword: optimizing fertilizer, oil palm, physiology response, morphology response, dolomit

Judul: Optimasi Pupuk Nitrogen, Fosfor, dan Kalium pada Kelapa Sawit (Elaeis guineensis Jacq.) Belum Menghasilkan Umur Dua Tahun
Abstrak: Fertilization is the one of the important factors to increase the vegetative growth of the two years old of oil palm. Fertilization can increase the availability of nutrition that needed by the plant. The one type of fertilizer that can be used as an alternative to improve soil fertility is single anorganic fertilizer. The purposes of this research were (1) to study the effect of N, P, K fertilizer on two years old plant of oil palm and (2) to determine the optimum rate of N, P, K fertilizer on two years old plant of oil palm. The researchs were conducted at IPB-Cargill Teaching Farm of Oil Palm, Jonggol, Bogor from April 2014 to March 2015. This research consisted of three experiment namely: (1) optimization of nitrogen fertilizer rate, there were five levels of N fertilizer rate: 0, 316, 632, 948, 1 264 g plant-1 year-1 (2) optimization of phosphorus fertilizer rate, there were five levels of phosphorus fertilizer rate: 0, 226, 453, 679, 905 g P2O5 plant-1 year-1, and (3) optimization of pottasium fertilizer rate, there were five levels of pottasium fertilizer rate: 0, 384, 768, 1 152, 1 536 g K2O plant-1 year-1. Each experimentations consisted of single factor using randomized block design with three replications. The result showed that nitrogen fertilizer increased quadratically plant height, frond production, stem girth, and number of stomata, but nitrogen fertilizer increased linierly leaf nutrient content. The optimum rate of nitrogen was 879 g N plant-1 year-1 for two years old of oil palm. Phosphorus fertilizer increased quadratically frond production, stem girth, leaf area of 17th frond, leaf chlorophyll, number of stomata, and phosphorus fertilizer increased linierly leaf nutrient content. The optimum rate of phosphorus was 604 g P2O5 plant-1 year-1 for two years old of oil palm. Pottasium fertilizer increased quadratically frond production, stem girth, leaf area of 17th frond, and number of stomata. The optimum rate of pottasium fertilizer was 972 g K2O plant-1 year-1 for two years old of oil palm.
Keyword: nutrition, morphology, stomata, critical nutrient level

Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix