Judul: Efektivitas Pengawetan Kayu pada Industri Mebel di Kabupaten Jepara
Abstrak: Furniture industry in Jepara Regency using juvenile wood and fast-growing timber species as raw material because of the limited supply from natural forest. Preservation is applied in the production process to protect from wood destroying organism attacks like termites that are easier to attack juvenile wood. The objective of this research was to determine the effectiveness of preservative that applied in furniture industry Jepara Regency against subterranean termites (Coptotermes curvignathus) attacks. The preservative contain active permethrin, chlorpyrifos, and a solution of hydrogen peroxide. Preservation methods used were brushing and soaking methods. Termites testing in laboratory scale method that used according to JIS K 1571-2004 standard. The results indicated that preservative used very effective to improve wood durability against subterranean termites (Coptotermes curvignathus) attacks. The effectiveness was shown by the average of preservation treatments samples were significantly different from the control sample at the 95% level for mortality, weight loss, and feeding rate termites. The average of retention of wood preservation in Jepara furniture industry was 4.69 kg/m3 it was still below the minimum standard of SNI 03-5010.1-1999 there was 8 kg/m3 for using under roof and 11 kg/m3 for using without the roof.
Keyword: termite, wood preservation, preservative

Judul: Karakteristik Pengeringan Kayu di Industri Mebel Kabupaten Jepara Jawa Tengah
Abstrak: Wood drying is an imperative process on producing exported wood furniture in Jepara. The process tends to be based on local characteristics. The objectives of this research were to understand characteristics of wood drying to finished wood products; and to understand benefits and drawbacks of wood drying based on local wise. The methods used were literature study and field research. Field research was conducted in nine furniture industries of Jepara Regency and in Wood Drying Laboratory, Forest Products Department, Faculty of Forestry, IPB. Wood drying methods used in Jepara’s furniture industries were commonly air drying, kiln drying and smoked wood. The average of the exported wood furniture moisture content was about 8.5 % - 11.2 %. The longest drying time average for air drying, smoked drying and kiln drying were respectively 20 days, 19 days and 12 days. The percentages of drying defects of air drying, kiln drying, and smoked wood were 21.4 %, 100 %, 100 %, respectively. Wood drying quality of Perum Perhutani teak, community teak and mahogany wood included good enough quality
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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