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: Production and Viability of Sorghum Seed Samurai 2 with  Different Harvesting Ages in Rainy Seasons
Abstrak: Penelitian ini bertujuan untuk mengevaluasi produksi dan viabilitas benih sorgum berdasarkan umur panen yang berbeda. Penelitian ini menggunakan sorgum varietas samurai 2 yang dirancang dengan rancangan acak kelompok (RAK) dengan 5 kelompok meliputi K1, K2, K3, K4, K5 dan 5 perlakuan umur panen berbeda meliputi 90 HST (P1), 95 HST (P2), 100 HST (P3), 105 HST (P4) dan 110 HST (P5). Data dianalisis dengan menggunakan ANOVA dan apabila perbedaan yang nyata terjadi maka dilakukan uji lanjut menggunakan uji lanjut Duncan. Peubah yang diukur adalah panjang malai, berat segar malai, berat kering malai, berat biji pipil, berat 1000 biji, jumlah biji, produksi biji kering, total biomassa segar malai, total biomassa kering malai dan viabilitas benih. Hasil penelitian menunjukkan bahwa umur panen 90 sampai 100 HST meningkatkan berat segar malai, berat kering malai, total biomassa segar malai, total biomassa kering malai, berat biji pipil, berat 1000 biji, dan produksi biji kering. Produksi dan viabilitas benih sorgum varietas samurai 2 terbaik pada waktu musim hujan yaitu pada umur panen 90 HST., This research was conducted to evaluate the production and viability of seed sorghum based on different harvesting ages. This research was use sorghum varieties of samurai 2 and designed a randomized block design (RDB) with 5 blocks which included K1, K2, K3, K4, K5 and 5 treatments of different harvesting age which included 90 DAP (P1), 95 DAP (P2), 100 DAP (P3), 105 DAP (P4) and 110 DAP (P5). The data were analyzed using ANOVA and any significant differences were further tested using duncan multiple range test (DMRT). The measured variable was panicle length, weight, dry weight; dry weight of seed per panicle, 1000 seeds weight, number of seeds, dry seed production; total panicle fresh and dry biomass; and seed viability. The results showed that the harvesting age of 90 to 100 DAP increased panicle weight and dry weight; total panicle fresh and dry biomass; seed dry weight, 1000 weight and production of seed. The best production and viability during the rainy season of sorghum seeds samurai 2 variety was harvested at age 90 DAP.
Keyword: harvest age, panicle, sorghum, viability, seed

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
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