Judul: Early Cutting with Different Intensities on Indigofera zollingeriana Seedings: Morphological Characteristics and Production
Abstrak: Pemangkasan tanaman pakan merupakan faktor penting karena dapat mempengaruhi laju pertumbuhan dan produksi, yang diduga akibat berubahnya kinerja hormon pertumbuhan seperti auksin dan sitokinin. Pemangkasan dini pada bibit tanaman Indigofera adalah salah satu upaya menginduksi kinerja hormon tumbuh untuk memicu pembentukan bagian vegetatif tanaman. Penelitian ini bertujuan untuk mendapatkan taraf intensitas pemangkasan dini optimal yang dapat menghasilkan pertumbuhan dan produksi Indigofera. Penelitian ini menggunakan rancangan acak kelompok dengan 4 perlakuan dan 4 ulangan. Perlakuan terdiri dari P0 : Tanpa pemangkasan, P1, P2, dan P3 berturut-turut pemangkasan setinggi 20 cm, 40 cm, dan 60 cm dari pangkal batang. Parameter morfologi yang diukur adalah tinggi tanaman, diameter batang, jumlah cabang, tunas, dan daun, sedangkan parameter produksi yang diukur meliputi proporsi daun dan batang, produksi segar, dan produksi kering. Data dianalisis menggunakan ANOVA dan perlakuan berbeda nyata akan diuji lebih lanjut dengan uji Duncan menggunakan program SPSS versi 25. Hasil penelitian menunjukkan bahwa perlakuan P3 memberikan hasil terbaik., Forage cutting is an important factor to determind growth rate and production. This may associated with growth hormone activities like auxin and cytokinin in the plant tissue. Pruning is one of the efforts to induce the performance of growth hormones to trigger the formation of vegetative parts of the plant. This research aimed to obtain the optimal level of early pruning intensity that can result in the growth and production of Indigofera. This study used a randomized group design with 4 treatments and 4 replications. The treatments consisted of P0 denoting without pruning, P1, P2, and P3, representing cutting intensity respectively 20 cm, 40 cm, and 60 cm from the stem base. The measured morphological parameters include plant height, stem diameter, leaf, branch, shoot count. Meanwhile, the measured production parameters include biomass fresh yield and dry yield. Data were analyzed using ANOVA, and significant different value of the parameters will be tested further with the Duncan test using the SPSS version 25 program. The results showed that the P3 treatment gave the best results.
Keyword: Indigofera zollingeriana, karakteristik morfologi, pemangkasan dini, pembibitan, produksi, early cutting, morphological characteristics, productivity, seeding

Judul: Growth Characteristics of Indigofera zollingeriana at Different Land Altitude in Conservation Areas.
Abstrak: Penelitian ini bertujuan mengevaluasi tingkat adaptasi pertumbuhan hijauan pakan Indigofera zollingeriana yang ditanam di kawasan konservasi pada ketinggian lahan berbeda. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) terdiri dari 3 perlakuan berdasarkan ketinggian lahan 900 mdpl (P1), 1000 mdpl (P2) dan 1300 mdpl (P3) dengan 5 ulangan. Peubah yang diamati yaitu intensitas cahaya, suhu, kelembaban, tinggi tanaman, diameter batang, jumlah cabang, jumlah daun dan jumlah tunas. Data dianalisis menggunakan ANOVA dan perlakuan berbeda nyata diuji lebih lanjut dengan uji Duncan menggunakan program SPSS versi 25. Analisis regresi dilakukan untuk mengukur pengaruh ketinggian lahan penanaman dengan tinggi tanaman Indigofera zollingeriana. Perbedaan ketinggian lahan penanaman Indigofera zollingeriana berpengaruh sangat signifikan (P<0,01) terhadap tinggi tanaman, diameter batang, jumlah cabang, jumlah daun dan jumlah tunas. Hasil analisis regresi memiliki kecenderungan negatif yaitu dengan nilai R2 = 0,6334, ketinggian lahan penanaman berpengaruh negatif terhadap tinggi tanaman Indigofera zollingeriana., This study aimed to evaluate the adaptation level of Indigofera zollingeriana forage growth planted in conservation areas at different altitudes. The study employed a Completely Randomized Design (CRD) consisting of 3 treatments based on different altitudes: 900 meters above sea level (P1), 1000 meters above sea level (P2), and 1300 meters above sea level (P3), each with 5 replications. The variables observed were light intensity, temperature, humidity, plant height, stem diameter, number of branches, number of leaves, and number of shoots. Data were analyzed using ANOVA, and significant treatment differences were further tested using Duncan's test with SPSS version 25. Regression analysis was performed to measure the influence of planting altitude on the height of Indigofera zollingeriana plants. The different planting altitudes of Indigofera zollingeriana significantly influenced (P<0.01) the height of the plants, stem diameter, number of branches, number of leaves, and number of shoots. The regression analysis showed a negative trend with an R2 value of 0.6334, indicating that planting altitude had a negative effect on the height of Indigofera zollingeriana plants.
Keyword: conservation area, Indigofera zollingeriana, morphological characteristics, land elevation

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: