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: Manajemen Produksi dan Pascapanen Daun Potong Asparagus  umbellatus Link, Philodendron xanadu Croat, Mayo & J.Boos, dan Phlebodium aureum (L.) J. Sm. di Kwekerij Figaro B.V., Naaldwijk, Belanda Selatan
Abstrak: Kegiatan magang dilaksanakan di Kwekerij Figaro selama empat bulan, mulai 1 Maret hingga 31 Juni 2023. Kegiatan magang bertujuan untuk meningkatkan pengetahuan dan keterampilan mahasiswa secara teknis dan manajerial khususnya dalam budidaya, penanganan panen dan pascapanen daun potong Asparagus umbellatus, Philodendron xanadu, dan Phlebodium aureum yang terdapat di Kwekerij Figaro. Metode yang digunakan dalam kegiatan magang adalah metode langsung dengan melakukan pengamatan secara langsung di lapang serta mengikuti semua kegiatan teknis budidaya tanaman hias daun mulai dari penanaman sampai pascapanen. Metode tidak langsung dilakukan dengan mempelajari data sekunder, berupa arsip perusahaan, laporan perusahaan dan studi psustaka. Berdasarkan hasil kegiatan magang diketahui bahwa tanaman hias daun dibudidayakan di dalam greenhouse agar dapat disesuaikan dengan suhu optimal dan kondisi pertumbuhan untuk tanaman. Total luas lahan greenhouse perusahaan seluas 21.200 m², dengan pembagian area produksi Asparagus umbellatus seluas 8.800 m² (41,5%) dapat memproduksi hingga sebanyak 86.650 tangkai dalam periode 1 bulan, Philodendron xanadu sebesar 1920 m² dapat memproduksi hingga sebanyak 50.480 tangkai dalam periode 1 bulan, dan Phlebodium aureum sebesar 480 m² dapat memproduksi hingga sebanyak 12.200 tangkai dalam periode 1 bulan. Setelah panen, daun potong disimpan dalam cooling room pada suhu 12℃. Kualitas daun potong yang dihasilkan oleh Kwekerij Figaro serta rantai pemasaran yang baik membuat 99,40% produksi dapat dipasarkan. Setelah mengikuti kegiatan magang ini, mahasiswa mendapat keterampilan teknik budidaya, panen dan pasca panen khususnya penentuan kriteria panen, pembuatan buket Asparagus umbellatus dan alur produksi ketiga spesies daun potong., The internship was conducted at Kwekerij Figaro for four months, from March 1 to June 31, 2023. The internship aimed to improve students' knowledge and skills technically and managerially, especially in cultivation, harvest handling and postharvest of cut foliage of Asparagus umbellatus, Philodendron xanadu, and Phlebodium aureum at Kwekerij Figaro. The method used in internship activities was direct method by making direct observations in the field and following all technical activities of leaf ornamental crop cultivation from planting to postharvest. The indirect method is carried out by studying secondary data, in the form of company archives, company reports, and literature studies. Based on the results of internship activities, it is known that ornamental plants are cultivated in the greenhouse to provide optimal temperature and growing condition for the crops. The total area of the company's greenhouse is 21.200 m², with the division of Asparagus umbellatus production area of 8.800 m² (41,5%) can produce up to 86.650 stems, Philodendron xanadu of 1.920 m² can produce up to 50.480 stems, and Phlebodium aureum of 480 m² can produce up to 12.200 stems, all in a period of 1 month. After harvesting, cut leaves are stored in a cooling room at 12°C. The good quality of cut leaves produced by Kwekerij Figaro and a good marketing chain make 99,40% of production marketable. After participating in this internship, students obtained skills in cultivation, harvesting and post-harvest techniques, specifically in determining harvesting criterias, Asparagus umbellatus bouquet making and production flows of the three species of cut foliage.
Keyword: cut foliage, leaf ornamental crop, greenhouse, production

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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