Judul: Harvest Age Optimization of Sorghum bicolor Variety Samurai 1: Growth and Feed Forage Biomass Production
Abstrak: Sorgum merupakan jenis tanaman serealia dari famili Poaceae yang mempunyai daya adaptasi tinggi terhadap lahan kekeringan. Penelitian ini bertujuan mengevaluasi pengaruh umur panen yang berbeda terhadap pertumbuhan dan produksi sorgum varietas Samurai 1. Metode penelitian diantaranya, persiapan lahan, pembuatan petak tanam, penanaman, pemupukan, pemeliharaan, pemanenan, dan pengeringan. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) dengan 4 perlakuan dan 4 ulangan. P70 = 70 HST (Hari Setelah Tanam), P80= 80 HST, P90 = 90 HST, dan P100 = 100 HST. Hasil penelitian menunjukkan bahwa perlakuan umur panen berpengaruh nyata (P<0,05) terhadap jumlah daun, berat kering batang, berat kering daun, berat kering malai, berat kering total, biomassa kering, dan brix batang. Akan tetapi, tidak memiliki pengaruh nyata (P>0,05) terhadap tinggi tanaman, diameter batang, rasio batang dan daun, serta biomassa segar. Kesimpulan penelitian ini yaitu pemanenan sorgum varietas Samurai 1 pada umur 90 HST menghasilkan biomassa kering terbaik dan pemanenan pada umur 80 HST memberikan nilai brix batang dan kandungan nutrien yang optimal.
Keyword: brix

Judul: Production and Seed Quality of Sorghum (Sorghum bicolor (L.) Moench) Samurai 1 Varieties with Different Harvesting Ages during The Rainy Season.
Abstrak: Penentuan umur panen yang tepat serta penggunaan benih bermutu erat hubungannya terhadap produksi tanaman sebagai pakan ternak. Penelitian ini bertujuan mengevaluasi kemampuan produksi dan viabilitas tanaman sorgum (Sorghum bicolor (L.) Moench) varietas Samurai 1 sebagai pakan ternak pada umur panen yang berbeda pada musim hujan. Rancangan acak kelompok digunakan pada 3 perlakuan umur panen, dengan 3 kelompok terhadap hasil pertumbuhan dan produktivitasnya. Rancangan acak lengkap digunakan pada 3 perlakuan umur panen, dengan 4 ulangan terhadap viabilitas benih. Perlakuan umur panen yaitu hari ke-100, 105 dan 110 hari. Hasil menunjukkan perlakuan tidak berbeda nyata terhadap tinggi tanaman, jumlah daun, diameter batang, berat segar biomassa, berat kering daun, berat kering batang, berat kering malai utuh, berat kering total jerami sorgum, berat kering brangkasan malai, berat kering biomassa malai, berat benih pipil kering, rataan jumlah benih kering, produksi benih kering, tetapi berbeda nyata terhadap berat 1000 benih kering dan viabilitas benih sorgum varietas Samurai 1. Umur panen 105 hari memberikan hasil terbaik untuk mendapatkan produksi biomassa dan kualitas benih tanaman., The determination of the right harvest age and the use of quality seeds are closely related to crop production as animal feed. This study aimed to evaluate the seed production and viability of sorghum (Sorghum bicolor (L.) Moench) Samurai 1 variety at different harvesting ages during rainy season. Randomized block design was used for 3 treatments of different harvesting age, with 3 blocks as replicants for growth yield and productivity. Completely randomized design was used for 3 treatments of harvesting age, with 4 replicates for seed viability. The harvest age was the 100th, 105th, and 110th days. The results showed that the treatments did not significantly affect plant height, number of leaves, stem diameter, total biomass, dry weight of leaves, dry weight of stems, dry weight of intact panicles, total weight of sorghum straw, dry weight of stover panicle, dry weight of panicle biomass, dry seed weight, average number of dry seeds, and dry seed production, but significantly affected the 1000 dry seed weight and viability of Samurai 1 sorghum seed. Harvesting at 105 days resulted in the best results for biomass production and seed quality
Keyword: production, sorghum, harvest age, viability

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
Keyword: