Judul: Optimalisasi kualitas silase daun  rami (Boehmeria nivea, L. GAUD) melalui penambahan beberapa zat additif
Abstrak: A research to study the influence of additives and ensiling times on ramie leaves silage qualities for ruminant have been studied in vitro using completely and block factorial 3 x 3 designs. Three types of water soluble carbohydrate (WSC) and dry matter sources as additives (A1 = cassava meal, A2 = pollard and A3 = corn meal) and three ensiling times (B1 = 28, B2 = 35, and B3 = 42 days) have been investigated. The degradability of organic matter to form VFA and protein to form NH3 were measured according to General Laboratory Procedure (1966), while the rate organic matter fermentation was measured follow the procedure of Menke et al., (1979). Value of pH and protein degradability were measured follow procedure of Naumann dan Bassler (1997) and Carro dan Miller (1999). The variable of this research consist of physical characteristic and fermentation parameters, fermentability and digestibility of the silages by ruminant have been determined in vitro. In generally, physical characteristic of ramie leaf silage are green brown, lactic acid odor and softer texture. Ramie leaf silage with additive corn meal (A3) have breakage. pH parameters showed that A1 acidified the silages faster than the A2 ones (3,62 vs 5,13). High pH of A3 (7,35) treatment was caused by the rought texture of corn meal used in this experiment. The silages were categorized as fermentable and high digestible feeds for ruminants (NH3 > 8,89 mM, VFA > 94.88 mM). Production gas for 24 hours incubation rumen liquor and estimation of organic matter digestibility (OMD) after 6 weeks ensiling time were around 72% and 50%.
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Judul: Evaluasi Kualitas Nutrien Silase dan Hay Daun Rami dalam Ransum Komplit untuk Ruminansia secara In Vitro
Abstrak: A research to evaluate the effect of ramie leaves silage and hay on ruminant complete mixed ration (CMR) on nutrient content, fermentability, and digestibility by in vitro method have been conducted. There were 7 CMR treatments i.e. P0 (control ration) = 50% napier grass + 50% concentrate, P1 = 30% napier grass + 20% ramie leaves silage + 50% concentrate, P2 = 20% napier grass + 30% ramie leaves silage + 50% concentrate, P3 = 10% napier grass + 40% ramie leaves silage + 50% concentrate, P4 = 30% napier grass + 20% ramie leaves hay + 50% concentrate, P5 = 20% napier grass + 30% ramie leaves hay + 50% concentrate, and P6 = 10% napier grass + 40% hay + 50% concentrate. Both ramie leaves silage and hay increased the CMR digestibility and nutrient content, except the crude fiber. Control ration had a higher crude fiber than silage and hay. The CMR which contain ramie leaves silage had higher nutrient digestibility compared to the other rations. Fermentability of CMR was measured by ammonia concentration, VFA, and gas production. Rations which added with ramie leaves hay (P4 – P6) had a higher gas production whereas rations added with ramie leaves silage (P1 – P3) had a higher rations VFA concentration and gas production compared to P0. Ammonia concentration of rations added with preserved ramie leaves were lower than control, however ammonia concentration in all treatments were in optimal range. Acetate proportion was higher in CMR which contain ramie leaves hay than CMR which contain silage although the nutrients digestibility were lower. Adding ramie leaves silage in rations resulted higher propionate and butyrate proportion than control and rations which added with ramie leaves hay. Either silage or hay ramie leaves can be used up to 40% as napier grass substitute in ruminant CMR. Keywords: Hay, ramie leaves, ruminant, silage
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Judul: Teknik penentuan posisi bintang berdasarkan pelat foto overlapping
Abstrak: Bintang adalah salah satu objek langit yang menarik untuk diamati. Untuk itu, pengetahuan tentang posisi bintang sangat diperlukan. Posisi bintang di langit dapat dihitung melalui foto bintang. Fotografi astronomi atau astrometri merupakan ilmu yang mempelajari metode untuk menentukan posisi bendabenda langit seperti bintang berdasarkan pelat foto (Kamp, 1967). Sebuah pelat foto berisi citra bintang-bintang yang sudah diketahui posisinya berdasarkan katalog dan citra bintang-bintang yang belum diketahui posisinya. Posisi bintang yang ada di katalog dinyatakan dengan (a,3). Bintang yang belum diketahui posisinya lebih banyak jumlahnya daripada bintang yang sudah diketahui posisinya. Citra bintang pada pelat foto berupa sebuah titik dalam bentuk tetap. Posisinya pada pelat merupakan hasil pengukuran pada bidang kartesius dan dinyatakan dengan (1;,fl). Hasil pengukuran tersebut kemudian direduksi menjadi koordinat terukur (x,y). Hubungan antara (a,3) dan (x,y) didekati dengan sebuah deret dengan konstanta-konsranta deret merupakan konstanta pelat. Nilai konstanta pelat diperoleh dengan menggabungkan hasil pengukuran posisi bintang pada masing-masing pelat menjadi sebuah persamaan normal (Jefferys, 1963). Hasil akhir dari gugus persamaan normal tersebut dijabarkan dalam bentuk nOlasi matriks partisi dan berupa sebuah sistem persamaan linier Ax = b di mana A adalah matriks jarang, dan x merupakan konstanta pelar yang akan dicari nilainya. Untuk menyelesaikan sistem persamaan linier terse but digunakan metode transformasi given. Konstanta pelat yang sudah diperoleh dengan menyelesaikan sistem persamaan linier di atas, kemudian disubtitusi ke sebuah persamaan untuk memperoleh posisi bintang yang tidak tercantum dalam katalog. .
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