Judul: Ethnobotanical studies of Rejang tribe around the protected forest of Bukit Daun Rindu Hati Village - Central Bengkulu Regency
Abstrak: Desa Rindu Hati memiliki potensi keanekaragaman hayati yaitu tumbuhan tetapi data dan informasi tentang pemanfaatan tumbuhan masyarakat Suku Rejang masih sangat kurang. Dalam hal ini salah satunya dapat dilakukan melalui kajian etnobotani. Penelitian ini bertujuan untuk mengidentifikasi jenis-jenis tumbuhan yang dimanfaatkan dan mengidentifikasi pemanfaatan tumbuhan yang dimanfaatkan oleh masyarakat Suku Rejang di Desa Rindu Hati. Penelitian dilakukan pada bulan Januari - Februari 2021 di Desa Rindu Hati. Alat dan bahan yang digunakan dalam penelitian antara lain perlengkapan wawancara dan perlengkapan eksplorasi. Metode pengambilan data yang digunakan yaitu studi literatur, penentuan responden, wawancara, Observasi partisipatif, survei lapangan, dan pembuatan herbarium. Diperoleh 171 jenis dari 66 famili tumbuhan yang dimanfaatkan Suku Rejang di Desa Rindu Hati. Tumbuhan yang dimanfaatkan paling banyak digunakan sebagai obat dengan jumlah 76 jenis. Habitus tumbuhan yang paling banyak yaitu herba sebanyak 62 jenis (36%). Bagian tumbuhan yang paling banyak digunakan yaitu daun sebanyak 58 jenis (31,2%)., Rindu Hati Village has biodiversity potential, especially for plants. In this case, one of them can be explore through ethnobotany studies. This study aims to identify the types of plants used and to identify the use of plants used by the Rejang Tribe in Rindu Hati Village. The research was conducted in February 2021 in Rindu Hati Village. The tools and materials that are used in the research include interview and exploration equipments. The method of data collection used are the study of literature, respondent determination, interview, participatory observation, field survey, and herbarium making. There are 171 species from 66 plant families that were used by the Rejang Tribe in Rindu Hati Village. Plants that are most widely used as medicine with a total of 76 types. The most abundant plant habitats were herbs as many as 64 species (37%). The part of the plant that was mostly used was the leaves of 58 species (31.2%).
Keyword: ethnobotany, plants, Rejang Tribe

Judul: Utilization of Medicine Plants in Bayureja Village, Sindang District, Majalengka Regency
Abstrak: Pengetahuan dan kearifan lokal menyebabkan masyarakat memanfaatkan tumbuhan obat. Penelitian ini bertujuan mengidentifikasi spesies tumbuhan obat yang dimanfaatkan, serta mengidentifikasi kearifan lokal masyarakat Desa Bayureja dalam memanfaatkan tumbuhan obat. Penelitian dilaksanakan pada bulan Februari 2022 di Desa Bayureja, Kecamatan Sindang, Kabupaten Majalengka. Pengambilan data dilakukan dengan metode wawancara, eksplorasi partisipatif, observasi lapang, dan studi pustaka. Masyarakat Desa Bayureja memanfaatkan sebanyak 78 spesies dari 37 famili tumbuhan obat. Famili Fabaceae banyak dimanfaatkan. Habitus tumbuhan obat didominasi oleh pohon dan bagian yang paling banyak digunakan yaitu daun. Cara penggunaan banyak dilakukan pada tubuh bagian dalam dengan cara diminum dan proses pengolahan direbus. Intensitas penggunaan yang banyak digunakan yaitu 2 x sehari. Sebagian besar tumbuhan obat berasal dari budidaya pekarangan. Penyakit yang sering dialami masyarakat yaitu penyakit saluran pencernaan. PT. Damar Kencana Wangi mengolah sereh wangi menjadi berbagai produk kesehatan., Local knowledge and wisdom causes people to use medicinal plants. This study aims to identify the medicinal plant species used, as well as identify the local wisdom of the Bayureja Village community in utilizing medicinal plants. The research was conducted in February 2022 in Bayureja Village, Sindang District, Majalengka Regency. Data were collected by interview, participatory exploration, field observation, and literature study. The people of Bayureja Village use 78 species from 37 families of medicinal plants. Fabaceae family is widely used. The habitus of medicinal plants is dominated by trees and the most widely used part is the leaves. How to use is mostly done on the inside of the body by drinking and boiling processing. The intensity of use that is widely used is 2 times a day. Most of the medicinal plants come from garden cultivation. Diseases that are often experienced by people are digestive tract diseases. PT. Damar Kencana Wangi processes citronella into various health products.
Keyword: bayureja village, local wisdom, medicinal plants

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: