Judul: Etnobotani aren (Arenga pinnata (Wurmb) Merr.) di Masyarakat Kasepuhan Ciptagelar, Resort Gunung Koneng, Taman Nasional Gunung Halimun Salak
Abstrak: Aren (Arenga pinnata (Wurmb) Merr.) merupakan sumberdaya hutan yang banyak dimanfaatkan masyarakat Desa Sirnarasa dan menjadi salah satu komoditas yang diunggulkan di kawasan TNGHS. Pemanfaatan aren yang dilakukan masyarakat Desa Sirnarasa semakin berkurang dan didominasi oleh orangtua. Hal tersebut dikhawatirkan dapat menyebabkan tidak adanya keberlanjutan dalam pemanfaatan aren dan berujung pada hilangnya pengetahuan lokal. Penelitian ini bertujuan untuk mengidentifikasi pengetahuan lokal masyarakat terhadap pemanfaatan aren, mengidentifikasi proses pengolahan aren menjadi produk, serta mengidentifikasi regenerasi petani aren di Desa Sirnarasa. Metode yang digunakan adalah wawancara dengan sistem semi terstruktur menggunakan teknik purposive sampling terhadap 30 KK, observasi lapang, dan studi pustaka. Pembuatan gula aren dan kolang-kaling merupakan bentuk pemanfaatan yang dilakukan masyarakat Sirnarasa. Pengolahan aren masih dilakukan secara tradisional. Diperlukan kerjasama antara berbagai pihak dalam pemanfaatan aren agar dapat meningkatkan kesejahteraan petani aren serta meningkatkan ketertarikan kaum muda untuk ikut memanfaatkan aren. Kata kunci: aren, desa Sirnarasa, pengetahuan lokal, Sugar palm (Arenga pinnata (Wurmb) Merr.) is a forest resource that is widely used by the people of Sirnarasa village and is one of the leading commodities in the GHSNP area. The use of sugar palm in Sirnarasa village is decreasing and now is dominated by the elderly. It is feared this could lead to the absence of sustainability in the use of sugar palm and lead to the loss of local knowledge. This study aims to identify local knowledge of the community on the use of sugar palm, identify the process of processing sugar palm into products, and identify the regeneration of sugar palm farmers in Sirnarasa village. The method used is an interview with a semi-structured system using a purposive sampling technique of 30 families, field observations, and literature study. Making palm sugar and palm fruit is a community use in Sirnarasa. Cooperation between various parties is needed in the use of sugar palm in order to improve the welfare of sugar palm farmers and increase the interest of young people to participate in the use of sugar palm. Keywords: palm sugar, Sirnarasa village, local knowledge
Keyword: aren, etnobotani, Desa Sirnarasa

Judul: Potential and Utilization of Aren (Arenga pinnata (Wurmb) Merr.) in the Buffer Village of Gunung Rinjani National Park
Abstrak: Aren (Arenga pinnata (Wurmb) Merr.) merupakan tumbuhan multiguna yang memiliki potensi nilai ekonomi dan ekologi yang tinggi. Masyarakat sekitar Taman Nasional Gunung Rinjani banyak yang melakukan kegiatan perekonomian berasal dari hasil tumbuhan aren. Penelitian ini bertujuan mengidentifikasi potensi populasi aren dan bentuk pemanfaatan aren di desa penyangga Taman Nasional Gunung Rinjani. Pengambilan data dilakukan melalui studi literatur, wawancara semi terstruktur dengan metode purposive sampling, observasi lapang, dan analisis vegetasi. Pemanfaatan paling besar terdapat pada bagian bunga jantan untuk penyadapan air nira sebagai bahan baku pembuatan gula aren. Pemanfaatan lain yang dilakukan oleh masyarakat adalah bagian bunga betina untuk menghasilkan kolang-kaling; ijuk untuk pembuatan sapu dan atap rumah; daun untuk pembungkus makanan, pembuatan sapu lidi, dan pembatas lahan; batang mudanya sebagai bahan makanan; serta batang tuanya untuk pembuatan gagang perkakas dan pembatas lahan. Populasi tumbuhan aren di sekitar Taman Nasional Gunung Rinjani termasuk kedalam kategori lestari. Perlu adanya kerjasama antar berbagai pihak dalam pemanfaatan aren untuk meningkatkan nilai komoditas aren., Sugar palm (Arenga pinnata (Wurmb) Merr.) is a multipurpose plant that has high potential economic and ecological value. Many people around the Gunung Rinjani National Park carry out economic activities derived from sugar palm products. This study aims to identify the potential of the sugar palm population and the form of sugar palm utilization in the buffer area of Gunung Rinjani National Park. Data were collected through literature study, semi-structured interviews with purposive sampling method, field observations, and vegetation analysis. The greatest utilization is found in the male flowers portion for tapping the water of nira as a raw material for making palm sugar. Another parts of sugar palm commonly utilized is the female flowers to produce kolang-kaling; fibers used to make brooms and roofs; leaves used to make broomsticks, wrapping food, and land dividers; young stems as food; as well as old trunk for the manufacture of tool handles and land dividers. The sugar palm population around Mount Rinjani National Park is included in the sustainable category. Cooperation between various parties is needed in the use of sugar palm to increase the value of sugar palm commodities.
Keyword: sugar palm, potential, utilization

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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