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.
Keyword: 

Judul: Daya Tetas Telur Itik Alabio dan Persilangan Cihateup-Alabio dengan Bahan Sanitasi Alami
Abstrak: Hatchability of duck lower than the chicken and quail. Dirty egg shell can cause low hatchability. The use of disinfectants is aimed to suppress the growth of bacteria on the eggshell. Lemon is a natural disinfectants. This research was aimed to determine hatchability of Alabio (A) and Cihateup-Alabio (CA) crossbreed duck eggs by using natural sanitary materials of lemon juice for soaking eggs. Egg weight, egg shape index, fertility, hatchability, hatching weight, and the death of the embryo were analyzed descriptively. The correlation between egg weight and hatching weight was subjected to regression analyses. Egg weight and egg fertility of CA duck was higher than Alabio duck. Alabio duck egg shape index was greater than that of CA duck. Hatchability of CA eggs was higher than that of Alabio duck. The most high embryo mortality occurred in the period of hatcher (> 25 days). Regression analyses revealed strong correlation between egg weight and hatching weight. The high egg weight produces a high hatching weight.
Keyword: Bogor Agricultural University (IPB), hatchability, fertility, cihateup-alabio crossbreeds, alabio duck

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