Judul: Studi Pemanfaatan Citra Landsat 8 untuk Pendugaan Potensi di Hutan Rakyat Kabupaten Kulon Progo Daerah Istimewa Yogyakarta
Abstrak: Potensi akan kayu dan tegakan yang berasal dari hutan rakyat meningkat pesat seiring dengan timbulnya ketertarikan masyarakat untuk membangun hutan rakyat. Hal ini disebabkan oleh manfaat dari pembangunan hutan rakyat mulai dirasakan oleh masyarakat. Untuk mempermudah dalam pengelolaannya, diperlukan suatu kegiatan yang dapat menghitung dengan cepat potensi yang ada pada hutan rakyat tersebut. Metode yang dapat digunakan yaitu metode penginderaan jauh dengan memanfaatkan teknologi citra Landsat 8. Tujuan penelitian ini adalah merumuskan model pendugaan potensi tegakan dan membuat peta sebaran potensi hutan rakyat Kabupaten Kulon Progo dari persamaan model terbaik menggunakan citra Landsat 8. Tahapan penelitian ini terdiri dari: pengumpulan data, pra-pengolahan citra, pengambilan data lapang, dan pengolahan data. Hasil pengolahan data menunjukkan bahwa model regresi terbaik, yaitu model eksponensial V = 0.274*e(8.107*NDVI) dengan nilai R2 sebesar 83.3%. Uji akurasi pemetaan potensi memiliki nilai overall accuracy sebesar 91.8% dan kappa accuracy sebesar 87.23%. Luas hutan rakyat di Kabupaten Kulon Progo sebesar 50 921.86 Ha dengan potensi hutan rakyat terbesar terdapat pada Kecamatan Samigaluh dengan luas hutan rakyat sebesar 6729.92 Ha dan total potensinya sebesar 823 565.20 m
Keyword: Landsat 8, private forest, potential, regression model

Judul: Pendugaan Potensi Hutan Rakyat Menggunakan Citra Landsat 7 ETM+ di Kabupaten Ciamis Bagian Utara
Abstrak: Development of forest outside the forest area managed state today can be an alternative solution to the problem of forest resource pressures. One such alternative is the developed of private forest that are socially, economically, and ecologically profitable. Increased potential of timber forest product on private forest have significance in private forest management activities. Therefore, it is necessary to have an estimate of potential of research activities in private forest. The purpose of this research is to formulate a Estimation model of potential of private forest using Landsat 7 ETM+ imageries and create a map of distribution potential of private forest using Landsat 7 ETM+ imageries in north of Ciamis Regency. Stages of this research consisted of: preparation, image processing, field data collection, field data processing, modeling, and a map of distribution potential of private forest. The results of analysis shows the correlation between the value of NDVI with value of standing volume is high relatively (> 0,800), this case explains that the value NDVI on Landsat 7 ETM+ imageries can be used in surmise standing volume. Based on the results of the regression analysis and mapping accuracy test, selected models are used for mapping the distribution of potential of private forest in north of Ciamis Regency is the exponential models is V = 20,905*℮(1,765*NDVI) with R2 values of 62,8%, Kappa Accuracy of 30,9%, and the value of Overall Accuracy of 56%. Overall the location of villages surveyed are had a potency between 44,6 m3/ha up to 78,3 m3/ha with a total potential of private forest between 1.366,9 m3 up to 70.868,4 m3.
Keyword: 

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: