Judul: Budidaya tebu (Saccharum officinarum L.) lahan kering di PG Madukismo PT Madubaru Yogyakarta dengan aspek khusus pelaksanaan pemupukan
Abstrak: Kegiatan magang dilaksanakan di wilayah kerja PG Madukismo PT Madubaru, Kabupaten Purworejo dan Kabupaten Gunungkidul sejak bulan Februari sampai bulan Juni 2015. Kegiatan magang bertujuan untuk mempelajari serta memperoleh pengalaman dan keterampilan bekerja secara nyata mengenai aspek teknis budidaya tebu. Aspek teknis yang dilakukan berupa aplikasi pemupukan pada tebu lahan kering di PG Madukismo, PT Madubaru, Yogyakarta. Petani tebu menggunakan pupuk ZA, NPK, dan pupuk organik bersubsidi yang didapat dengan mengajukan Rancangan Definitif Kebutuhan Kelompok (RDKK) Pupuk Bersubsidi. Dosis yang tercantum pada RDKK Pupuk Bersubsidi adalah ZA 6 ku ha dan NPK 4 ku ha. Petani wilayah Purworejo yang merupakan petani lama dan pada umumnya menambah sendiri dari dosis rekomendasi pada RDKK Pupuk Bersubsidi dengan dosis rata-rata ZA 7.5 ku ha¹ dan NPK 4.7 ku ha Petani wilayah Gunungkidul yang merupakan petani baru memakai dosis yang sesuai dengan RDKK Pupuk Bersubsidi. Kedua wilayah kurang efektif dalam cara pemupukan tanaman tebu. Produktivitas wilayah Purworejo lebih tinggi dibanding wilayah Gunungkidul karena pengaruh iklim, potensi lahan, dan ketepatan kegiatan budidaya.
Keyword: Gunungkidul, New farmer, Experience farmer, Purworejo, RDKK of subsidized fertilizer, Dry land, Upland sugarcane, Fertilization method, Iklim dan tanah, Budidaya tebu

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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