Judul: Faktor-Faktor Produksi Dalam Pemenuhan Target Sadapan Getah Pinus di KPH Pekalongan Barat Divisi Regional Jawa Tengah Perum Perhutani
Abstrak: Produksi getah pinus merupakan produk utama hasil hutan bukan kayu di KPH Pekalongan Barat. Permasalahan yang dihadapi penyadap kurang aktif, waktu penyadapan tidak sesuai jadwal, dan ukuran pecok terlalu besar. Tujuan dari penelitian ini mengetahui pola produksi tahunan getah pinus, menentukan faktor yang mempengaruhi produksi getah pinus, dan mengukur persen kerusakan pohon pinus. Tahapan penelitian ini terdiri dari penentuan lokasi penelitian, penetapan responden, pengumpulan data, dan analisis data. Hasil penelitian menunjukkan bahwa di RPH Moga pada tahun 2019 sampai dengan 2021 tidak mencapai target, sedangkan di RPH Karangsari dari tahun 2017 sampai dengan 2021 mencapai target. Faktor yang mempengaruhi antara lain penyadap di RPH Moga kurang aktif dan curah hujan yang tinggi. Tingkat persen kerusakan pohon tertinggi di RPH Karangsari dengan jumlah quare sebanyak 5 quare sebesar 28,50%. Pada RPH Moga tingkat persen kerusakan pohon tertinggi pada quare yang berjumlah 4 quare sebesar 23,91%. Rata-rata tingkat persen kerusakan pohon RPH Karangsari lebih besar dibandingkan RPH Moga sebesar 23,33%., Pine sap production is the main product of non-timber forest products in FMU West Pekalongan. Problems faced such as the tappers are not active, the tapping time is not on schedule, and the size of the pecok or the axe is too big. The aims of this research to determine the annual production pattern of pine resin, determine the factors that influence the production of pine resin and meazure the percentage of damage to pine trees. The stages of this research consist of determining the research location, finding respondents, collecting data, and analyzing data. The results shows that in 2019 to 2021, Moga Forest Management Resort did not reach the target, while in Karangsari Forest Management Resort 2017 to 2021 the target was achieved. The factors that cause it to occur are the less activeness of tappers in Moga Forest Management Resort as well as high rainfall. The highest percentage of tree damage at Karangsari Forest Management Resort with a total of 5 quares is 28,50%. While the highest percentage of damage to the tree at Moga Forest Management Resort in 4 quares is 23,91%. The average percentage of damage to Karangsari Forest Management Resort (RPH) trees is greater than Moga Forest Management Resort (RPH) by 23,33%.
Keyword: Production targets, sap production factors, the percentage of tree damage

Judul: Pengaruh Tingkat Kerusakan Pohon Akibat Penyadapan terhadap Produktivitas Getah Pinus di KPH Cianjur Jawa Barat
Abstrak: Profitability targets of Perum Perhutani for pine resin production tend to increase every year, resulting in overtapping and have a bad impact on the tree stands, lowering the productivity of pine resin. Therefore, the use of drilling method was chosen for tapping. The tapping areas are smaller and the recovery of tapping is relatively short so that tree damage can be minimized. The objective of this study was to get a description of various levels of tree damage and resin productivity, to learn about the effect of tree damage on productivity levels of pine resin and to obtain a model to estimate the relationship between the level damage of pine tree and pine resin productivity. Of the 400 overtapped pine trees, the level of tree damage ranged from 4.11-85.54%, the average was 44.58%, the median was 46.16% and the standard deviation was 17.26%. Resin productivity ranged between 0-4.58 g/tree/day, the average was 0.77 g/ tree/day, the median was 0.54 g/tree/day, the mode was 0.13 g/tree/day and the standard deviation was 0.71 g/tree/day. The higher the damage level caused by resin tapping, the lower the pine resin productivity. Pine resin productivity can be predicted by the tree damage level with the best regression model in this study, that is, using a model of: Y=(1.63697+(-0.10739)X)/(1+(-0.04606)X+(-0.00145)X²)
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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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