Judul: Kontinuitas Ketersediaan Bahan Baku Industri Pengolahan Kayu Rakyat (Studi Kasus di Kecamatan Leuwisadeng dan Nanggung Kabupaten Bogor)
Abstrak: The development of private forest in Indonesia encourages entrepreneurs to develop timber processing business such as sawmill, including in Bogor Regency. Case study in Leuwisadeng and Nanggung Sub-District showed private owned timber processing industries are generally classified into a small industry that often having financial difficulty to buy raw materials. This resulted the industry cannot operate for several months in a year. The increasing demand of sawn timber has made industries to fulfill needs of raw material which is obtained not only from private forest around, but also from other areas outside Bogor Regency. For the next two years, private forest in Leuwisadeng and Nanggung Sub-District is unable to fulfill needs of industrial raw materials so that the industry still had to supply raw materials from other areas in order to continue the production of sawn timber.
Keyword: Bogor Agricultural University (IPB), private forest, raw materials, timber processing industry

Judul: Kontinuitas Ketersediaan Bahan Baku Industri Pengolahan Kayu Rakyat (Studi Kasus Di Kecamatan Leuwiliang Dan Rumpin, Kabupaten Bogor)
Abstrak: Hutan rakyat memiliki peranan penting dalam perekonomian masyarakat dan pertumbuhan industri pengolahan kayu rakyat. Masalah terbesar pada aspek pengolahan yaitu jumlah dan kontinuitas sediaan bahan baku dari hutan rakyat. Tujuan penelitian ini adalah menganalisis kontinuitas, wilayah asal bahan baku, dan mengukur besarnya kontribusi hutan rakyat terhadap ketersediaan bahan baku. Lokasi dan petani hutan rakyat dipilih secara purposive sampling, serta teknik snowball sampling dan metode wawancara recalling untuk industri penggergajian kayu yang telah beroperasi minimal selama satu tahun. Potensi hutan diukur secara sensus (luas <1000 m²) dan sampling (luas >1000 m²) dengan petak ukur berbentuk lingkaran. Bahan baku industri tetap tersedia dan kontinu tahun 2009 sampai 2013 yang dipengaruhi oleh faktor modal perusahaan. Pemasok bahan baku terbesar dari dalam Kecamatan Leuwiliang dan Rumpin, terbesar kedua dari luar kecamatan, dan terkecil dari luar Kabupaten Bogor. Kontribusi hutan rakyat dalam Kecamatan Leuwiliang sebesar 96.4%, luar kecamatan sebesar 3%, dan luar Kabupaten Bogor sebesar 0.6%, sedangkan dalam Kecamatan Rumpin sebesar 72%, luar kecamatan sebesar 25%, dan luar Kabupaten Bogor sebesar 3%.
Keyword: bahan baku, hutan rakyat, kontinuitas, kontribusi, wilayah asal

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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