Judul: Ethnobotany of medicinal plants in the Karon tribe in Senopi Village Tambrauw Regency West Papua
Abstrak: Suku Karon merupakan salah satu etnik yang tinggal di Kampung Senopi Kabupaten Tambrauw, Papua Barat. Suku Karon dalam kehidupan sehari-hari dengan memanfaatkan berbagai sumberdaya alam yang berada di lingkungan sekitarnya, salah satunya dengan memanfaatkan tumbuhan untuk mengobati berbagai macam penyakit. Penelitian ini bertujuan untuk mengidentifikasi pengetahuan etnobotani tumbuhan obat masyarakat Suku Karon dan status konservasi spesies tumbuhan obat yang dimanfaatkan oleh Suku Karon. Penelitian ini dilaksanakan pada bulan Juli-Agustus 2020. Data pengatahuan etnobotani masyarakat Suku Karon diperoleh melalui wawancara dengan metode snowball sampling. Terindentifikasi 30 spesies tumbuhan obat yang yang dimanfaatkan Suku Karon di Kmapung Senopi. Tumbuhan obat yang dimanfaatkan masyarakat dikelompokan menjadi 24 manfaat obat. Status konservasi tumbuhan obat yang dimanfaatkan Suku Karon, teridentifikasi hanya 1 spesies tumbuhan obat dengan status terancam (Endangered) berdasarkan IUCN, yaitu Pterocarpus indicus. Kata Kunci : etnik, etnobotani, suku karon, tumbuhan obat, The Karon tribe is one of the ethnic groups who live in Senopi Village, Tambrauw Regency, West Papua. The Karon tribe in their daily life by utilizing various natural resources in the surrounding environment, one of which is by using plants to treat various diseases. This study aims to identify the knowledge of ethnobotany of medicinal plants of the Karon Tribe and the conservation status of medicinal plant species used by the Karon Tribe. This research was conducted in July-August 2020. Data on the ethnobotany knowledge of the Karon Tribe were obtained through interviews with the snowball sampling method. Identified 30 species of medicinal plants used by the Karon Tribe in Senopi Village. Medicinal plants used by the community are grouped into 24 medicinal uses. The conservation status of medicinal plants used by the Karon Tribe, identified only 1 species of medicinal plants with Endangered status based on the IUCN, namely Pterocarpus indicus Keywords: ethnic, ethnobotany, karon tribe, medicinal plants
Keyword: Ethnic, Ethnobotany, Karon tribe, Medicinal plants

Judul: Etnobotani dan Potensi Tumbuhan Berguna di Kampung : Keay, Kabupaten Kutai Barat, Kalimantan Timur.
Abstrak: Keay Village is one of villages in West Kutai Regency, East Kalimantan. There are four ethnic groups occupying this village, i.e. Dayak, Javanese, Toraja, and Bugis. Dayak is the dominant ethnic group occupying the village, which still has traditional wisdom/knowledge in plants use. Ethnobotany is expected to document and hand on the knowledge of Dayak Benuaq ethnic group in using plants, and keep the knowledge from being loss. Data were collected through literature study, interview, field survey and inventory, vegetation analyses, and herbarium collection. Data on plants species found were classified in to classification of use, classification of illnesses, habitués percentage and parts of plants used, important value index, Shannon-Wienner species diversity index, and percentage of useful plants potential. There were 396 plant species found through ethnobotany and vegetation analyses, which was categorized into three categories i.e. plant species found through ethnobotany (285 species), plant species found through vegetation analyses in natural forest (158 species), plant species found through vegetation analyses in hevea plantation (34 species). There were 285 species belong to 78 families which uses had been known and grouped into 16 use groups. There were 53,79% of plants species in natural forest had the potential as useful plants, while in hevea plantation there were 50% of that species had the potential as useful plants. Dominant plant species in natural forest was keranyiq (Fordia johorensis) with IVI (Important Value Index) of pole level as much as 19,69%, sapling (25,46%), and seedling (24,67%). In hevea plantation, dominant plant species was hevea (Hevea brasiliensis) with IVI the highest IVI of tree level as much as 300%, pole (284,63%), sapling (143,59%), and seedling (52,42%). Plants use most widely used for medicinal as much as 95 species of 43 families. The community uses more plants from the forest than from the plantation, because there were more useful plants species in the forest. Potential useful plants at the forest of Keay village included mara uleq (Eurycoma longifolia), uwe (Korthalsia sp., Calamus sp., Daemonorops sp.), empulung (Asplenium nidus), and kerakap (Platycerium bifurcatum). Other potential other than plants potential in the natural forest was hevea (Hevea brasiliensis).
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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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