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: Post-recovery Pine Tapping Productivity at KPH Bogor Regional Division of West Java and Banten Perum Perhutani
Abstrak: Permintaan produksi getah pinus terus meningkat, namun produksi getah pinus menurun. Salah satu penyebabnya yaitu karena tegakan pinus mengalami jenuh sadap (belum saatnya untuk ditebang namun bidang sadap sudah habis). Produktivitas getah pinus pascapemulihan yaitu sadapan pinus yang dilakukan pada bidang sadap yang telah mengalami penutupan luka belum diketahui. Penelitian ini bertujuan untuk mengukur persentase pemulihan bidang sadapan pinus metode quarre dan menganalisis produktivitas sadapan pinus pascapemulihan pada kedua kelas umur pohon. Rancangan percobaan yang digunakan adalah rancangan acak kelompok terdiri dari dua perlakuan yaitu sadapan pascapemulihan dan kontrol sedangkan kelompok yaitu tegakan pinus kelas umur (KU) IV dan IX. Hasil penelitian menunjukkan rata-rata pemulihan bidang sadapan pinus KU IX lebih tinggi dibandingkan KU IV. Rata-rata produktivitas getah pinus (g/pohon/hari) perlakuan pascapemulihan lebih rendah dibandingkan kontrol pada kedua kelas umur yaitu KU IV dan KU IX perlakuan pascapemulihan berturut-turut 8,11 g/pohon/hari dan 9,15 g/pohon/hari sedangkan perlakuan kontrol berturut-turut 11,42 g/pohon/hari dan 10,59 g/pohon/hari. Perlakuan (pascapemulihan dan kontrol) sadapan getah pinus menghasilkan produktivitas yang berbeda sedangkan kelas umur menghasilkan produktivitas yang sama., The demand for pine resin continues to increase along with the declining of pine resin production. One of the reasons is because the pine trees have become saturated with tapping (it is not proper yet to cut down, but the tapping fields have run out). Post-recovery pine resin productivity, namely pine tapping in a tapping area that had undergone closure of the tapping wound not yet known. This study aimed to measure the percentage of pine tapping field recovery using the quarre method and to analyze the productivity of post-recovery pine resin in both age classes of trees. The experimental design used a randomized block design consisting of two treatments, namely post-recovery and control, while the group consisted of pine stands of age class IV and IX. The results showed that the average recovery of the pine tapping field in age class IX was higher than age class IV. The average productivity of pine resin (g/tree/day) in post-recovery treatment was lower than the control in both age classes, namely age class IV and IX in post-recovery treatment, respectively 8.11 g/tree/day and 9.15 g/tree/day while the control treatments were 11.42 g/tree/day and 10.59 g/tree/day, respectively. Treatments (post-recovery and control) on tapped pine resin had a different productivity, while the groups (age class) had the same productivity.
Keyword: post-recovery, pine resin, productivity, tapping field recovery

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.
Keyword: