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: Development of Radicle Emergence Test on  Soybean Seeds (Glycine max L.) using Digital Image Processing
Abstrak: Pengolahan citra digital merupakan suatu teknik yang dapat digunakan untuk mengidentifikasi mutu benih dalam waktu singkat. Penelitian ini bertujuan mengembangkan metode pengujian cepat vigor pada benih kedelai (Glycine maxL.) menggunakan metode pemunculan radikula atau radicle emergence (RE) dengan pengolahan citra digital. Penelitian ini menggunakan rancangan kelompok lengkap teracak dengan empat ulangan dan dikecambahkan pada suhu 25 ± 2 ºC. Pengambilan citra dilakukan setiap dua jam sekali dalam rentang waktu 36-54 jam setelah benih dikecambahkan. Penelitian ini dilakukan dengan mengamati jumlah benih yang memiliki panjang radikula = 2 mm. Data panjang radikula tersebut kemudian dianalisis korelasi dan regresi terhadap tolok ukur mutu fisiologis benih, antara lain daya berkecambah, indeks vigor, potensi tumbuh maksimum, kecepatan tumbuh, dan mean radicle emergence time (MRET). Penelitian yang dilakukan memperoleh hubungan korelasi kuat antara panjang radikula = 2 mm dengan tolok ukur indeks vigor, kecepatan tumbuh, dan MRET pada benih kontrol serta korelasi kuat pada tolok ukur daya berkecambah dan indeks vigor pada cekaman salinitas NaCl konsentrasi 0,35% dan 0,7%. Korelasi kuat antara panjang radikula = 2 mm dengan tolok ukur vigor benih lainnya pada waktu pengecambahan 44 jam., Digital image processing is a technique that can be used to identify seed quality in a short time. This research aims to develop a rapid vigor testing method for soybean (Glycine max L.) seeds using the radicle emergence (RE) method with digital image processing. This research used a randomized complete group design with one factor with four replications and germinated at 25 ± 2 ºC. Images were taken every two hours within 36-54 hours after the seeds were germinated. This research was conducted by observing the number of seeds that had radicle length = 2 mm. The radicle length data was then analyzed for correlation and regression against the benchmarks of seed physiological quality, including germination, vigor index, maximum growth potential, growth speed, and mean radicle emergence time (MRET). The research conducted obtained a strong correlation on the benchmarks of vigor index, growth speed, and MRET in control seeds and a strong correlation on the benchmarks of germination and vigor index under NaCl salinity stress concentrations of 0.35% and 0.7%. Strong correlation between radicle length = 2 mm and other seed vigor benchmarks at germination time of 44 hours.
Keyword: ImageJ, percentage of radicula growth amount, germination period, seed viability, seed vigor

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: