Judul: Pengelolaan Tanaman Tebu (Saccharum officinarum L.) di Pabrik Gula Madukismo, PT. Madubaru, Yogyakarta: dengan Aspek Khusus Mempelajari Produktivitas Tiap Kategori Tanaman
Abstrak: The study of the productivity of the various categories of sugarcane held in the Madukismo Millsworking area, Madubaru Company, Yogyakarta. This activity began in February 13 to May 14, 2012. The sample is taken at Sleman and Bantul district. The method used is the direct field observation, data from the division of plant productivity, as well as interviews with farmers. The results obtained on the productivity of down land is higher than up land. Differences in land characteristics influence the productivity of sugarcane. In addition, the downland productivity tended to decrease from the plant cane (PC) to ratoon crop (RC) in each subsequent season. For up land, there is higher productivity at ratoon cane I (RC 1) increase from low productivity in the plant cane (PC) and then back on every ratoon crop the following season. To overcome the low productivity of ratoon sugarcane needed to do the loading or replanting, or ratoon intensif nurse.
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Judul: Budidaya tebu (Saccharum officinarum L.) lahan kering di PG Madukismo PT Madubaru Yogyakarta dengan aspek khusus pemupukan beberapa kategori tanaman tebu lahan kering
Abstrak: The internship was conducted at PG Madukismo PG Madubaru Yogyakarta beginning 14 February 2012 to 15 Mei 2012. The special purpose is study fertilization of some category of upland sugarcane at PG Madukismo PT Madubaru Yogyakarta. Fertilization in PG Madukismo is important because one in order to achieve high productivity is a good fertilizer. Most of the fields in the PG Madukismo was upland. There are two types of cultivated sugar cane that is PC (Plant Cane) and RC (Ratoon Cane) Fertilizer used in PG Madukismo is the dose recommended by the P3GI and considered by PG Madukismo and farmers. Parties responsible for the extraction of manure from the barn to the application to sugarcane was foreman and field assistant. Dosage fertilizer for PC (Plant Cane) are 11 ku/ha Madros, 5 ku/ha ZA and 5 ku/ha Phonska while for RC (Ratoon Cane) are 5 ku/ha ZA and 5 ku/ha Phonska. The data obtained were analyzed using t-test. From the results obtained for plants PC or RC I obtained the best productivity of sugarcane grown on land that has a typology mild soil type, irrigation well (pump) and the current drainage there are Kledokan field in Magelang which have productivity 598 ku /ha and Sikendal field in Temanggung which have productivity 693 ku/ha.
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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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