Judul: Evaluasi Kelayakan Investasi Hutan Rakyat Jabon di Desa Brebeg Kecamatan Jeruklegi Kabupaten Cilacap
Abstrak: Jabon community forest in rural land of Brebeg, Jeruklegi, Cilacap is the first time for planting project accomplished. The development of this forest requires an investment feasibility evaluation to see if the business is feasible to be continued or requires more reviews. The evaluation consisted of nonfinancial and financial aspects. The nonfinancial evaluation’s result (technical aspect, market aspect, social aspect, and environment aspect) showed that jabon is more feasible to be developed than sengon and mahogany. The result of financial evaluation obtained NPV Rp19 517 832 in strata I; Rp26 494 773 in strata II; and Rp84 494 319 in strata III, obtained BCR 2.81 in strata I; 2.76 in strata II; and 4.09 in strata III, obtained IRR 43.14% in strata I; 42.59% in strata II; and 56.53% in strata III. As such, the community forest in rural land of Brebeg is feasible based on financial and nonfinancial aspects. In addition, the switching value analysis showed that neither output price decrease nor variable cost increase was not affected the business sensitivity.
Keyword: switching value, investment feasibility, jabon, community forest

Judul: Financial Analysis of Land Use with Agroforestry in Cibeber II Village, Leuwiliang District, Bogor Regency
Abstrak: Pengelolaan pengusahaan hutan rakyat di Desa Cibeber II meliputi pengusahaan tanaman kayu mapun non kayu yang berasal dari hutan rakyat milik pribadi maupun tanah garapan yang dimanfaatkan untuk kesejahteraan dan kebutuhan sehari-hari masyarakat setempat. Tujuan dari penelitian ini memberikan informasi mengenai kelayakan usaha hutan rakyat dari sebagian pola tanam yang terdapat di hutan rakyat Cibeber II. Berdasarkan hasil analisis finansial dengan pola monokultur dan agroforestri layak untuk dikembangkan melalui tiga indikator yaitu NPV, BCR dan IRR. Dari hasil analisis tersebut usaha hutan rakyat dengan pola agroforestri sengon dengan delapan tanaman pengisi lebih menguntungkan dibandingan dengan pola agroforestri sengon dengan tiga tanaman pengisi dan agroforestri sengon, kayu afrika, meranti dan dua tanaman pengisi serta monokultur sengon dengan nilai NPV sebesar Rp478.903.719,00 BCR sebesar 29,15 dan IRR tidak terdefinisi (nilai selalu positif)., The management of community forest in Cibeber II Village includes the exploitation of both timber and non-timber plants originating from privately owned community forests and arable land which are used for the welfare and daily needs of the local community. The purpose of this study is to provide information about the financial feasibility of several cropping patterns found in the Cibeber II community forest. Based on the results of financial analysis, both monoculture and agroforestri patterns are feasible to be developed according to three indicators, namely NPV, BCR and IRR. From the results of the analysis, community forest business with sengon agroforestry pattern with eight filler plants is more profitable than the sengon agroforestry pattern with three filler plants and sengon agroforestri, African wood, meranti and two filler plants and sengon monoculture with an NPV are Rp478.903.719,00 BCR is 29,15 and IRR is undefined (value is always positive).
Keyword: Agroforestry, Cibeber II Village, Financial analysis, Private forests

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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