Judul: Etnografi, Etnobotani dan Etnoekologi Masyarakat Etnik Batak Toba di Kecamatan Simanindo Kabupaten Samosir
Abstrak: Hasil penelitian didapatkan bahwa kearifan lokal masyarakat Etnik Batak Toba Kecamatan Simanindo adalah kearifan lokal terkait ritual keagamaan dengan memanfaatkan tumbuhan. Pemanfaatan tumbuhan dalam ritual keagamaan seperti prosesi pemakaman, tasyakuran hasil bumi, tahun baru agama, dan mengkramatkan suatu spesies tumbuhan. Tumbuhan tersebut adalah Ficus benjamina, Themeda gigantea, Cordyline fruticosa, Oryza sativa, Crinum jagus, Ocimum americanum. Tumbuhan tersebut dijaga keberadaannya dengan cara membudidayakannya di sekitar ladang, sawah dan pekarangan rumah. Selain hal tersebut juga ada pemanfaatan tumbuhan dalam tradisi menyirih/menginang seperti tumbuhan sirih (Piper bettle), tembakau (Nicotiana tabacum), gambir (Uncaria gambir), pinang (Areca cathecu) dan penggunaan tumbuhan sebagai pewarna ulos, seperti, kayu jabi-jabi (Sida acuta), daun salaon (Indigofera tinctoria), kayu sona (Pterocarpus indicus), daun tayom, kunyit (Curcuma domestica) dan harumonting (Rhodomyrtus tomentosa).
Keyword: Cosmos, Corpus, Etnobotani, Etnoekologi, Etnografi

Judul: Ethnobiology of thesamin
Abstrak: This ethnobiological research focus on the ethnoecological, ethnobotanical and ethnozoological study of the adaptation process (correlating to management concept, impact on people’s activities, and technology usage) of Samin Community. The goals of this research were to study the beliefs, knowledge, and practice the Samin community for the comprehensive understanding of landscape use and management, ant to reveal the local knowledge of Samin community in managing their natural resource (plants and animals) whice include species diversity, the index of ecological importance value (INP), and the index of cultural significance (ICS). The study was conducted during the period of August 2009 to December 2011. The research was carried out in 7 villages in 4 districts, namely: (1) Larikrejo and (2) Kaliyoso (Kudus District); (3) Bombong and (4) Ngawen (Pati District); (5) Klopoduwur and (6) Tambak, Sumber (Blora District); (7) Jepang, Margomulyo (Bojonegoro, East Java). The research data consisted of ecological, ethnobotanical, ethnozoological and ethological data. Data collection using direct observation; open ended and structured interview, and participant observation. The results showed that the Samin society has a fairly good knowledge of biological resources and their environment. Use practices and management of natural resources is reflected in the form units of the environmentals and biological resources contained therein. Knowledge of the spatial environment simply divided into two main units, namely: mondokan (house and yard), and lemah garapan includes: fields (sawah), moor (tegalan) and teak (alas jati). Paddy field, dry field, yard, garden, teak forests, marsh ponds, and rivers were the places where the cultivation of a wide variety of production activities of plants and animals which were conducted to meet their basic needs. The research obtained more than 300 of plant species in the Samin settlement, which 235 species among those were useful for their life. Utilization of those plants include for food (118 species), traditional medicine and cosmetics (74 species), building materials (17 species) equipment (15 species), firewood (16 species), animal feed (27 species), fiber materials and the straps (3 species), ritual materials (26 species), toxic materials (2 species), pest control materials (16 species), environmental indicators (5 species), and ornamental plants and fences (45 species). Based on the role and utilization of animals, it can be grouped into: animal protein source (21 species), pets (7 species), pests of cultivated plants (17 species), pests of livestock (3 species), pest predators (11 species), animals for medicine (10 species), animals for ritual (1 species), and wildlife (35 species). The Samin community the resources and the environment only as necessery. They always maintained a harmonious relationship with nature.
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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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