Judul: Permodelan Pertumbuhan dan Produksi Kelapa Sawit Pada Berbagai Taraf dan Periode Penunasan Pelepah
Abstrak: The number of leaf frond influence oil palm yield, especially fresh fruit bunch weight and production. The objective of this research was to obtain oil palm growth and production model for different levels and periods of frond pruning. The experiment was conducted at PT. Astra Agro Lestari, Pangkalan Bun, Central Kalimantan, from August 2011 to February 2012. The experiment was arranged in randomized block design with two factors and three replications. The first factor was numbers of unpruned frond and the second factors was pruning periods. The frond treatments consisted of 41-48, 49–56, and 57–64 fronds. The periods of pruning treatment consisted of first period (early to mid rainy season):September– December, second period (mid to end of rainy season):Januari–April, and third period (dry season):May–August. Model has been able to predict 75% variable for production and fresh fruit bunch weight for different levels and periods of pruning.
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Judul: Penerapan Teknik Konservasi Tanah dan Air Dalam Meningkatkan Produksi Kelapa Sawit.
Abstrak: Indonesia region like Lampung is less suitable for oil palm plantation, because of long dry season and low rainfall. One of the effort to solve the drought is application of soil and water conservation technique such a ridge terrace and silt pit. This research was aimed to study effectiveness of ridge terrace and silt pit treatment which were accomplished with “biopori” and vertical mulches on soil moisture content as well as growth and production of oil palm plantation; to study the correlation of soil moisture content and growth and production of oil palm. The research was conducted in Afdeling III, Rejosari Management Unit PT Perkebunan Nusantara VII, South Lampung. The area of research consisted of 3 blocks namely block 1 (375) with ridge terraces treatment, block 2 (415) with no treatment, and block 3 (414) with silt pits treatment. The research results show that application of conservation techniques were able to increase monthly of average soil moisture content where in the figure in block 1, block 3, and block 2 are 48.32%, 45.21%, and 43.64%, respectively. The appearance of frond fracture of the three blocks is not significantly different. The production of oil palm in block 1 (ridge terraces) and block 3 (silt pits) are higher than block 2 (control). The production of block 1, 2, and 3 are 25 343.18, 22 677.38, and 24 251.97 kg/ha/year, respectively. Correlation value of soil moisture content towards oil palm production are very low. The correlation of block 1 is 0.175, block 2 is 0.100, and block 3 is 0.059. Correlation value of number ripe fresh fruit bunches and female infloresence nine months before on block 1, 2, and 3 are 0.628, 0.230, and 0.539, respectively.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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