Judul: Produktivitas Oleoresin Pinus dengan Berbagai Metode Sadapan di Indonesia
Abstrak: Komoditas Hasil Hutan Bukan Kayu (HHBK) terus dikembangkan seiring menurunnya produksi kayu dan meningkatnya deforestasi di Indonesia serta lebih menguntungkan dibandingkan dengan produksi kayu. Oleoresin pinus merupakan HHBK yang banyak dimanfaatkan di Indonesia. Produktivitas oleoresin pinus dipengaruhi berbagai hal, salah satunya metode sadapan. Modifikasi atau pembaharuan metode penyadapan diperlukan untuk efesiensi penyadapan berkelanjutan baik segi ekonomi maupun kelestarian lingkungan. Tujuan penelitian ini adalah mengetahui produktivitas oleoresin pinus dengan berbagai metode sadapan. Metode yang sering dipakai di Indonesia ialah quarre, riil, dan bor. Metode quarre memiliki keunggulan dari segi produktivitas tinggi dan biaya rendah, namun metode bor memiliki keunggulan dari segi kerusakan pohon rendah dan kualitas oleoresin tinggi. Jenis stimulansia yang optimal bagi metode quarre dan riil ialah anorganik, sedangkan metode bor ialah campuran, Non-Timber Forest Products (NTFP) commodities continue to be developed in line with decreasing timber production and increasing deforestation in Indonesia and are more profitable than timber production. Pine oleoresin is an NTFP which is widely used in Indonesia. The productivity of pine oleoresin is influenced by various factors, one of which is the lead method. Modification or renewal of the tapping method is necessary for sustainable tapping efficiency, both from an economic perspective and for environmental sustainability. The purpose of this study was to determine the productivity of pine oleoresin using various lead methods. The methods that are often used in Indonesia are quarre, real, and borehole. The quarre method has the advantage of high productivity and low cost, but the drilling method has the advantage of low tree damage and high oleoresin quality. The optimal type of stimulant for the quarre and real method is inorganic, while the borehole method is mixed.
Keyword: pine oleoresin, productivity, tapping method

Judul: Penggunaan Stimulansia ETRAT pada Penyadapan Getah Pinus merkusii, Pinus oocarpa dan Pinus insularis di Hutan Pendidikan Gunung Walat
Abstrak: Indonesia has the level of biodiversity that is high enough. One of them is pine tree. Pine trees can be used as a timber, but it also produce resin that can be processed into Gumrosin and turpentine. In Gunung Walat University Forest has 3 species kind of pine are P. merkusii, P. oocarpa, and P. insularis. Pine tapping productivity can methode by increase tapping technique and optimally at using stimulant. In Gunung Walat University Forest only pine tapping productivity from P. merkusii had be knowing. Therefore, it is necessary to research about productivity Pine resin the use of stimulant ETRAT especially P. oocarpa and P. insularis. The research uses 40 trees for each species of pine, 20 trees are used as control (without the stimulant) and 20 other trees using stimulant. The periode treatments resin collecting once 3 days with total observation as many 15 times. The observation weighed use scales digital. Based on this research, the highest average productivity is P. merkusii the use of stimulant ETRAT treatment that is 19,93 grams/quarre/day, followed by P. oocarpa and P. insularis with respective 19,29 grams/quarre/day and 14,95 grams/quarre/day. The percentage of increase in the resin after using stimulant ETRAT on P. merkusii that is equal 117,81%, 62,85% for P. oocarpa and 76,19% for P. insularis. The use of stimulant ETRAT value-added productivity of the pine resin tapping amound Rp 76,85/quarre/day for P. merkusii, Rp 51,73/quarre/day for P. oocarpa, and Rp 48,8/quarre/day for P. insularis. The use of stimulant ETRAT influence productivity of pine tapping all three species of pine. Based on Duncan test, the treatment of stimulant ETRAT on P. oocarpa is no diffrent to P. merkusii and P. insularis. The use of stimulant ETRAT influence research showed productivity the tapping P. merkusii with P. insularis.
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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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