Judul: Development of Seed Vigour Test with Radicle Emergence for IPB Sweet Corn (Zea mays saccharata Sturt.) using Digital Image Processing
Abstrak: Seiring dengan berkembangnya teknologi, kemajuan pengujian benih juga ikut mengalami peningkatan. Salah satu implementasi teknologi dalam pengujian benih adalah dengan menggunakan pengolahan citra digital. Penelitian bertujuan mengembangkan metode uji cepat vigor dengan metode pemunculan radikula (Radicle Emergence) pada benih jagung manis (Zea mays saccharata Sturt.) koleksi IPB dengan menggunakan pengolahan citra digital. Penelitian dilakukan di Laboratorium Penyimpanan dan Pengujian Mutu Benih, Departemen Agronomi dan Hortikultura (AGH), Fakultas Pertanian, Institut Pertanian Bogor pada bulan Januari hingga Mei 2023. Penelitian ini menggunakan rancangan kelompok lengkap teracak dengan empat ulangan. Benih jagung manis diperoleh dari koleksi Divisi Pemuliaan Tanaman IPB. Pengamatan dimulai jam 58 hingga 74 jam setelah pengecambahan. Terdapat empat kategori panjang radikula yang digunakan, yaitu kriteria panjang radikula ≥ 1 mm, panjang radikula ≥ 2 mm, panjang radikula ≥ 50% panjang benih, dan panjang radikula ≥ panjang benih. Persamaan yang diperoleh dari analisis regresi belum dapat digunakan untuk menduga RE pada benih jagung manis dengan indeks vigor sangat rendah dengan tingkat viabilitas sedang. Periode pengecambahan 60 sampai 64 jam dapat digunakan sebagai acuan awal untuk pengembangan metode uji cepat radicle emergence menggunakan pengolahan citra digital., Along with the development of technology, the progress of seed testing has also increased. One of the technology implementations in seed testing is to use digital image processing. The aim of the study was to develop a vigor rapid test method using the radicle emergence method on IPB sweet corn (Zea mays saccharata Sturt.) seeds using digital image processing. The study was conducted at the Seed Storage and Quality Testing Laboratory, Department of Agronomy and Horticulture (AGH), Faculty of Agriculture, Bogor Agricultural University from January to May 2023. This study used a randomized complete block design with four replications. Sweet corn seeds were obtained from the collection of the Plant Breeding Division of IPB. Observations began 58 to 74 hours after germination. There are four categories of radicle length used, namely the criteria for radicle length ≥ 1 mm, radicle length ≥ 2 mm, radicle length ≥ 50% of seed length, and radicle length ≥ seed length. Based on the results of the correlation analysis, the RE percentage values in the four categories of radicle length produced had a significant correlation with the vigor index (IV) benchmark. The equations obtained from the regression analysis cannot be used to predict RE in sweet corn seeds with a very low vigor index and moderate viability. The germination period of 60 until 64 hours can be used as an initial reference for developing radicle emergence (RE) rapid test methods using digital image processing.
Keyword: germination period, ImageJ, percentage of radicula growth amount, radicle length, strain

Judul: Development of Seed Vigour Test Method with Radicle Emergence using Digital Image Processing for Sweet Corn (Zea mays saccharata Sturt.)
Abstrak: Penelitian ini bertujuan untuk mengembangkan metode pemunculan radikula dengan pengolahan citra digital sebagai uji vigor benih jagung manis yang lebih cepat, akurat, dan objektif. Citra kecambah jagung manis yang diamati pada setiap periode pengecambahan diambil menggunakan kamera digital, kemudian diolah menjadi data numerik oleh ImageJ. Rancangan percobaan yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) faktor tunggal. Hasil penelitian menunjukkan bahwa metode RE benih jagung manis dengan citra digital yang memiliki kategori panjang radikula minimal ≥ panjang benih (± 0,95 cm) pada 66 jam ± 15 menit di suhu 20 ± 2 ºC berkorelasi cukup erat dengan parameter indeks vigor, daya berkecambah, potensi tumbuh maksimum, daya tumbuh lapang, dan tinggi tanaman 2 MST. Metode pengujian RE benih jagung manis dengan pengolahan citra digital dapat menggambarkan 15,8 – 35,6% keragaman mutu fisiologis benih lainnya. Metode pengujian RE benih jagung manis dengan pengolahan citra digital berpotensi dan patut untuk dikembangkan menjadi metode baru untuk pengujian vigor benih., This research aims to develop radicle emergence method using digital image processing as a faster, more accurate, and objective seed vigour test for sweet corn. The image of sweet corn germinate that were observed during the germination period was captured using a digital camera, then processed into numerical data by ImageJ. The experimental design was arranged in a single factor Randomized Complete Group Design (RCBD). The result showed that RE test for sweet corn seeds using digital image processing which has the radicle length category minimum equal as the seed length (± 0,95 cm) at 66 hours ± 15 minutes at 20 ± 2 ºC is closely correlated with the parameters vigour index, germination, maximum growth potential, field emergence, and plant height 2 WAP. RE test method for sweet corn seeds using digital image processing ables to describe 15,8 – 35,6% diversity of other seeds physiological qualities. RE test method for sweet corn seeds using digital image processing has the potential and deserves to be developed as a new method for seed vigour test.
Keyword: accurate, digital camera, radicle length, seed physiological qualities

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.
Keyword: