Judul: Application of AMMI multi response with weighted principal component on stability test of java tea plants
Abstrak: Kumis kucing (Orthosipon aristatus Miq.) adalah tanaman obat yang dapat membantu memperbaiki fungsi ginjal. Permintaan yang tinggi akan pasokan kumis kucing mendorong adanya pembudidayaan tanaman ini. Pada tahun 2012- 2013 Balai Penelitian Tanaman Rempah dan Obat (Balittro) melakukan percobaan multilokasi terhadap enam genotipe kumis kucing. Penelitian ini bertujuan untuk mengklasifikasikan daya adaptasi genotipe kumis kucing. Data yang digunakan adalah hasil percobaan multilokasi tanaman kumis kucing di tiga lokasi selama tiga musim panen. AMMI merupakan salah satu pendekatan yang dinilai sangat baik untuk menganalisis data hasil percobaan multilokasi. Pada umumnya AMMI masih terbatas pada respon tunggal. Penggabungan respon dengan pembobotan berdasarkan komponen utama adalah salah satu metode yang menghasilkan validasi yang baik untuk menangani masalah tersebut. Hasil analisis AMMI pada respon produktifitas tanaman menghasilkan dua genotipe yang stabil yaitu genotipe E dan F. Respon morfologi tanaman hanya menghasilkan satu genotipe stabil yaitu genotipe B. Sedangkan pada respon gabungan total genotipe yang stabil adalah genotipe B dan E., Java tea (Orthosipon aristatus Miq.) Is a medicinal plant which can help improve kidney function. High demand for supply of java tea encourage cultivation of this crop. Balai Penelitian Tanaman Rempah dan Obat (Balittro) conduct multilocation experiment of the six genotypes java tea in 2012-2013. This study aims to classify java tea adaptability. Data that used is a result of multilocation experiment at three location during three harvest season. AMMI is statistic methode that can used to analyze data from multilocation experiment. AMMI is generally limited to a single response. Combining response with the weighted on principal component is one method which generates good validation to handle that problems. The results of AMMI analysis on the response of plant productivity to produce two stable genotype is genotype E and F. The morphological responses of plants only produce a stable genotype is genotype B. While in combination total responses the stable genotype is genotype B and E. Keywords: java tea, weighting the principal component, multilocation experiment
Keyword: kumis kucing, pembobotan komponen utama, percobaan multilokasi

Judul: Pertumbuhan, Biomassa Daun, dan Kerapatan Trikoma Kelenjar pada Kumis Kucing (Orthosiphon stamineus Benth.) dengan Pemberian Berbagai Pupuk Organik dan Naungan
Abstrak: One of the medicinal plants which are cultivated in Indonesia is java tea plant (Orthosiphon stamineus Benth.). Influence of shade and fertilizer factor to the growth of plants needs to be known in cultivating this plant. This study aimed to examine the effect of various types of organic fertilizers and shading conditions on growth of the plant, leaf biomass, chlorophyll content, and density of glandular trichomes on the java tea plant. This experiment used a factorial completely randomized design with two factors. The first factor was shading conditions, consist of no-shade (N0) and 50% shade (N1). The second factor was the planting medium, which consist of soil (V1), mixture of soil and goat manure (V2), soil and chicken manure (V3), and soil and compost (V4). Parameters observed were growth parameters, chlorophyll content, and density of glandular trichomes. The results showed that the optimal growth of java tea plant was provided by planting medium with enrichment of goat and chicken manure fertilizers no-shade. Shading treatment increased chlorophyll content, but decreased density of glandular trichomes in both adaxial and abaxial leaf surfaces. Density of glandular trichomes in abaxial was higher than that of adaxial surface.
Keyword: shading, Orthosiphon stamineus Benth, organic fertilizers, glandular trichomes

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: