Judul: Pendugaan Umur Itik Alabio dan Cihateup Berdasarkan Tempat Tumbuh Bulu Tetap pada Bagian-Bagian Tubuh
Abstrak: Duck selection for replacement is difficult for farmers, as day old duck (DOD) are generally sold in a group although they have different ages. The purpose of this study was to estimate the age of ducks (cihateup and alabio) through the growth of fixed feather on the body. A total of 143 alabio ducks eggs originate from Borneo and 32 cihateup ducks from Tasikmalaya had hatched in Animal Husbandry Hatching Laboratory then grew up at the Field Laboratory of Poultry Production, Bogor Agricultural University. The results showed that the overall changing of hatching feathers into fixed feathers on both types of ducks is observes successively from the chest, armpits, upper back, tail, lower back, neck, wing primary and secondary wings. The alabio ducks hatching feathers substitution into fixed feathers were faster than cihateup ducks. Cihateup ducks showed changing of hatching feathers into fixed feathers in its chest in weeks 4, while the alabio ducks showed changing in the chest, armpit and upper back on the same week. Alabio ducks changed all the fixed feathers in their body on weeks 6, mean while cihateup duck on weeks 7.
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Judul: Nisbah Jenis Kelamin Hasil Penetasan Telur Itik Cihateup dan Alabio
Abstrak: Duck eggs are more difficult to hatch than chicken eggs as the duck does not incubate their eggs and the duck eggs need more time to hatch (in 28 days). This study aimed to determine the sex ratio of DOD (Day Old Duck) from two different breeds, namely cihateup from Tasikmalaya West Java and alabio from South Kalimantan. This experiment was conducted from May 2012 to July 2012 at the Hatchery Laboratory of Animal Science Faculty of IPB. 500 eggs consist of 300 alabio eggs and 200 cihateup eggs were used in this experiment. Temperature, humidity, egg weight, egg shape index, hatching weight and mortality were measured. The data of egg weight, egg shape index, and hatching weight were analyzed using t-test, the data of sex ratio DOD were analyzed using chi-square test. The result showed that there were no significant difference between egg weight and egg shape index on sex ratio. Sex ratio of male and female cihateup ducks was equal (50%:50%), however the sex ratio of alabio ducks was different (32%:68%). Mortality rate was affected by sex of duck (P<0.05). The Higher mortality was occured at early (day 0-7) and late (day>25) hatching period.
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Judul: Aproksimasi Fungsi Sinus dan Kosinus sebagai Kombinasi Linear dari Fungsi Eksponensial
Abstrak: Salah satu gagasan yang menarik dalam matematika adalah aproksimasi suatu fungsi oleh fungsi lain. Sebagai contoh, fungsi polinom dapat diaproksimasi menggunakan deret Taylor atau fungsi persamaan diferensial dapat diaproksimasi menggunakan deret Fourier. Adapun fungsi yang dapat mengaproksimasi fungsi lain salah satunya adalah fungsi eksponensial. Kemungkinan mengaproksimasi fungsi dengan kombinasi linear dari fungsi eksponensial dari bentuk eˣ, e²ˣ, ... dianggap sebagai perkembangan sejajar dengan gagasan Deret Taylor yang mengaproksimasi fungsi dengan kombinasi linear dari segi fungsi kuadrat. Fungsi sin x dan cos x digunakan sebagai target untuk menilai seberapa baik aproksimasi yang dilakukan oleh fungsi yang diberikan. Aproksimasi fungsi sinus dan kosinus menggunakan hampiran Taylor lebih akurat dibandingkan dengan aproksimasi menggunakan fungsi eksponensial.
Keyword: Aprosimaksi eksponensial, aproksimasi fungsi, aprosimaksi Taylor, fungsi eksponensial