Judul: Study of the Vegetative Organs Character of Aromatic  Ginger Accessions (Kaempferia galanga L.) from Kediri Residence as a  Functional Vegetable
Abstrak: Daun kencur termasuk sayuran fungsional yang belum banyak dikonsumsi oleh masyarakat. Produksi sayur ini hanya berpusat pada beberapa daerah saja. Penelitian ini bertujuan mengelompokkan aksesi kencur yang berasal dari Karesidenan Kediri berdasarkan karakter morfologi, agronomi, dan kimia. Penelitian dilakukan di Kebun Percobaan di Dusun Pandan Lor, Desa Canggu, Kecamatan Badas, Kabupaten Kediri, Jawa Timur mulai bulan September 2021 hingga bulan April 2022 dengan perlakuan perbedaan 10 aksesi kencur yang berasal Karesidenan Kediri. Rimpang kencur ditanam pada bedengan berukuran 2 m x 1,6 m dengan jarak tanam 25 cm x 25 cm dan tiga ulangan percobaan. Hasil penelitian ini menunjukkan adanya tiga kelompok aksesi yaitu AK-1, AK-2, dan AK-3. Terdapat perbedaan bobot panen yaitu aksesi A5 dengan bobot terberat dan aksesi A10 dengan bobot ter-ringan. Uji organoleptik menunjukkan perbedaan pada aroma dan kekerasan daun. Aksesi A1 dan A4 merupakan aksesi paling harum sedangkan aksesi A5, A8, dan A10 merupakan aksesi paling tidak beraroma. Aksesi A4, A5, dan A7 merupakan aksesi paling keras sedangkan aksesi A8 dan A10 merupakan aksesi yang paling lunak. Kandungan flavonoid dalam kuersetin daun sama pada semua aksesi. Aksesi kencur paling cocok untuk sayur terdapat pada aksesi A8. Semua aksesi sekarang telah di simpan di Departemen Agronomi dan Hortikultura, Fakultas Pertanian, IPB University., Aromatic ginger leaves is a functional vegetables is not widely known and consumed by the public. Aromatic ginger leaves are only produced in certains regions of Java. The aim of this research is to evaluate the grouping of aromatic ginger accessions from Kediri Residence based on morphology, agronomy, and leaf chemical characteristic. The research was carried out in experimental field on Pandan Lor Hamlet, Canggu Village, Badas District, Kediri Regency, East Java started from September 2021 until April 2022 often aromatic ginger accessions from Kediri were evaluated. Aromatic ginger rhizome planted in 2 m x 1,6 m sized of planting bed with 25 cm x 25 cm planting distance and three experimental replication. The result of this research showed that the ginger accessions can be separated into three accession groups of aromatic ginger, named AK-1, AK-2, and AK-3. There is a difference in harvest fresh weight, A5 accessions had the heaviest weight and A10 had the lowest. Organoleptic test showed the differences in the leaf aroma and hardness of different accessions. A1 and A4 is the most fragrant accessions, while A5, A8, and A10 is the least scented accessions. A4, A5, and A7 is the most hardness accessions, while A8 and A10 is softest accessions. Quercetin content in leaves was similar in all accessions. The most suitable aromatic ginger vegetables for fresh comsumption is the A8 accesions. All accessions are now conserved at the Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University.
Keyword: accessions, aromatic ginger, cluster, harvest, vegetative

Judul: The Effect of Planting Distance and Shade Level on the Production of Aromatic Ginger Leaves (Kaempferia galanga L.) as a Vegetable
Abstrak: Kencur dapat dimanfaatkan sebagai sayur. Efisiensi penggunaan lahan pada budidaya kencur menurun dari tahun 2016 hingga 2018, sehingga dapat diasumsikan produksi daun kencur sebagai sayur juga menurun. Penelitian ini dilakukan untuk menganalisis jarak tanam dan tingkat naungan yang sesuai untuk memaksimalkan produktivitas daun kencur sebagai sayur. Penelitian ini telah dilaksanakan di Kebun Percobaan Leuwikopo, Institut Pertanian Bogor, Dramaga, Bogor mulai dari bulan September 2022 hingga Januari 2023. Penelitian ini menggunakan Rancangan Split Plot Kelompok Lengkap Teracak (Split PlotRKLT) dua faktor, yaitu jarak tanam dan tingkat naungan. Tiga taraf jarak tanam yang digunakan, yaitu 15 cm x 15 cm, 20 cm x 20 cm, dan 25 cm x 25 cm serta serta tiga taraf tingkat naungan, yaitu tanpa naungan, naungan 50%, dan naungan 75%. Terdapat 9 kombinasi perlakuan yang diulang sebanyak tiga kali, sehingga terdapat 27 unit satuan percobaan. Naungan 75% menghasilkan pertumbuhan dan perkembangan bobot brangkasan kencur terbaik. Jarak tanam 15 cm x 15 cm menghasilkan produksi bobot basah dan bobot layak jual terbaik.
Keyword: efficiency, growth, harvest, productivity

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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