Judul: Cultivation, Harvesting, and Post-harvest of Philodendron giganteum, Philodendron selloum, and Philodendron xanadu at PT PDMA, Bogor, West Java
Abstrak: Kegiatan magang dilaksanakan di PT Pesona Daun Mas Asri (PDMA) selama empat bulan yang dimulai dari 18 Januari hingga 17 Mei 2021. Tujuan kegiatan magang adalah meningkatkan pengetahuan, pengalaman, dan keterampilan kerja mahasiswa secara teknis maupun manajerial khususnya dalam budidaya, panen, dan pascapanen daun potong Philodendron giganteum, Philodendron selloum, dan Philodendon xanadu pada PT PDMA. Metode yang digunakan dalam kegiatan magang adalah metode langsung dengan melakukan dan mengambil data di lapangan dan tidak langsung dengan studi literatur dan pengambilan data dari dokumentasi PT PDMA. Berdasarkan hasil kegiatan magang diketahui bahwa budidaya Philodendron dilakukan pada bedengan yang berada di shadehouse menggunakan paranet dengan tingkat naungan 75%. Perbanyakan masing-masing tanaman untuk penyediaan bibit dilakukan dengan cara stek batang dengan jarak tanam 40 x 40 cm. Pemupukan dilakukan sebanyak dua kali setiap bulan menggunakan campuran 1 Kg NPK dan 500 g urea per bedeng berukuran 32 x 1,5 m dengan metode sebar rata. Hasil pengamatan menunjukkan pertumbuhan daun Philodendron dengan rata-rata pertambahan tinggi tanaman tiap minggu sebesar 1,4 cm pada Philodendron selloum serta 1,8 cm pada Philodendron giganteum dan Philodendron xanadu. Kriteria daun yang siap dipanen berdasarkan panjang daun ≥ 15 cm dan lebar daun ≥ 10 cm yang dipanen menggunakan gunting panen. Perlakuan pascapanen terdiri dari pembersihan, sortasi, pengkelasan, pengemasan, dan penyimpanan. Penyimpanan daun potong menggunakan air pada medium kapas basah. Pemasaran dilakukan langsung ke pelanggan yang terbagi menjadi end user dan trader., The internship activity was conducted at PT Pesona Daun Mas Asri (PDMA) for four months starting from 18th January until 17th May 2021. This internship aimed to improve student technical and managerial knowledge, work experience, and skills, especially in cultivation, harvest, and post-harvest of Philodendron giganteum, Philodendron selloum, dan Philodendon xanadu at PT PDMA. The data is collected through direct observation by conducting and taking the data in the field and indirect methods by literature study and documentation taken from PT PDMA. Based on the result of the internship, it is known that Philodendron cultivated on beds in shadehouses from a paranet with a shade rate of 75%. Each plants propagated by stem cutting for nursery. The plant spacing for each plants is 40 x 40 cm. Fertilization done twice in a month using 1 Kg NPK and 500 g urea per beds sized 32 x 1,5 m with broadcasting method. The observation resulted Philodendron growth increase 1.4 cm for Philodendron selloum and 1.8 cm for Philodendron giganteum and Philodendron xanadu. The foliage harvesting criteria based on foliage length ≥ 15 cm and foliage width ≥ 10 cm that harvested with scissor. The post-harvest phase consists of cleaning, sorting, grading, packaging, and storage. Cut foliage storage method use wet cotton as a medium of water. The company marketing done directly to the customer that divided into trader and end user.
Keyword: daun potong, Philodendron, produksi, tanaman hias, cut foliage, ornamental plant, production

Judul: Cultivation, Harvest, and Postharvest of Cut Foliage Monstera deliciosa LIebm, Cordyline fruticosa (L.) A.Chev., and Asparagus virgatus Baker at PT Pesona Daun Mas Asri, Bogor, Jawa Barat
Abstrak: Produksi daun potong merupakan industri yang sedang berkembang di Indonesia; daun potong digunakan untuk rangkaian bunga dan dekorasi. Kegiatan magang dilaksanakan di PT Pesona Daun Mas Asri selama 4 bulan dimulai 24 Januari hingga 24 Mei 2022. PT Pesona Daun Mas Asri merupakan kebun pembibitan khususnya untuk produksi daun potong. Magang bertujuan untuk meningkatkan wawasan dan kemampuan mahasiswa pada aspek teknis dan manajerial pengelolaan perusahaan pertanian. Magang juga menambah kemampuan mahasiswa dalam berinteraksi dengan karyawan kebun, meningkatkan wawasan mahasiswa pada pemasaran daun potong di pasar bunga secara langsung, serta meningkatkan networking mahasiswa. Kegiatan magang meliputi kegiatan teknis produksi dan manajerial, mulai dari penanaman, panen, hingga penanganan pascapanen daun potong. Teknik budi daya, panen, hingga pascapanen yang tepat diperlukan untuk memperoleh daun potong berkualitas. Pertumbuhan tanaman dari ketiga spesies juga diamati setiap minggu selama 7 minggu selama 4 bulan magang dilaksanakan. Daun Monstera deliciosa dapat dipanen pada minggu ke 5 dan panen selanjutnya 2-3 minggu kemudian sejak daun baru tumbuh, daun Cordyline fruticosa dapat dipanen pada minggu ke 3 selanjutnya 2-3 minggu kemudian sejak daun baru tumbuh, sedangkan daun Asparagus virgatus dapat dipanen pada minggu ke 7 dan panen selanjutnya 7 minggu setelah anakan baru tumbuh. Budi daya daun potong M. deliciosa dan C. fruticosa dilakukan pada shadehouse paranet, sedangkan budi daya A. virgatus dilakukan pada shadehouse plastik UV. Penanganan pascapanen terdiri dari pembersihan, sortasi, grading, dan pengemasan. Tangkai daun potong dilapisi kapas basah untuk menjaga kesegaran daun potong. Sistem pemasaran daun potong terdiri dari pelanggan trader dan pelanggan end user., Cut foliage production is a growing industry in Indonesia; they are used mainly for floral arrangements and indoor decoration. An internship was conducted at PT Pesona Daun Mas Asri for 4 months starting from 24th January until 24th May 2022. PT Pesona Daun Mas Asri is a nursery that specializes in the production of tropical foliages. The internship aimed to expand student knowledge and practical experience on technical and managerial aspects of managing an agricultural farm. The internship can improve student ability in interaction between farm employee, improve student knowledge about cut foliages marketing system in flowers market, also improve student networking with others. The internship activities include technical and managerial activities, from production, harvest, and postharvest of the cut foliages. Cultivation, harvest, and postharvest techniques are needed to obtain quality of cut foliage. Plant growth of the three species were measured every week for 7 weeks during the 4 months internship. Monstera deliciosa leaves can be harvested on the 5th week and the next harvest in 2-3 weeks after the new leaves grow, Cordyline fruticosa can be harvested on the 3rd week and the next harvest in 2-3 weeks after the new leaves grow, meanwhile Asparagus virgatus leaves can be harvested on the 7th week and the next harvest in 7 weeks after the new tillers grow. M. deliciosa and C. fruticosa are grown in shadehouses with net roof, while A. virgatus grown under shadehouses with UV plastic roof. Postharvest handling consists of cleaning, sorting, grading, and packaging. The stalks of cut foliage are covered by wet cotton to maintain the
Keyword: filler, leaf ornamental plants, production, marketing system

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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