Judul: Penyelenggaraan Makanan, Tingkat Konsumsi Dan Analisis Preferensi Atlet Di Sma Negeri Ragunan Jakarta
Abstrak: The appropriate of nutrition is a main basic for athletes to perform their ability in a competition. SMA Negeri Ragunan Jakarta is one of the institution that provides any training programs of some sports. This institution supplies foods every day to the athletes. The objective of this research is for knowing the role of food organization system, the consumption level of energy and macronutrients, and also the preference of the athletes in SMA Negeri Ragunan Jakarta. The research was conducted by using analytic descriptive design from April to May 2009. Samples was chosen with the purposive sampling. The amount of sample is 40 athletes, divided into 5 athletes of archery, 12 athletes of volley, 11 athletes of swimming and 12 athletes of atlethic. The food organization system in SMA Negeri Ragunan Jakarta have required the standard of food organizer. The food organization system have worked well. More than half of samples (67.5%) have deficit in the level consumption of energy. Almost of samples (62.5%) consumed protein between 66.7 and 100 percent (adequate). Most of samples (77.5%) consumed fat less than 20 percent and 97.5 percent of samples consumed carbohydrate more than 70 percent. Research shows that the time dividing have a correlation with the level of energy consumption. The level of energy consumption increase when the meal divides in a appropriate time. The appropriate of time serving and cleanness of canteen have significantly positive correlated with the level consumption of energy
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Judul: Konsumsi suplemen pada atlet remaja di SMA Ragunan Jakarta
Abstrak: Tujuan penelitian ini adalah menggambarkan konsumsi suplemen pada atlet remaja di SMA Ragunan Jakarta. Desain penelitian ini menggunakan cross sectional study. Subjek diambil dari siswa SMA Ragunan yang bersedia mengikuti penelitian dan berada di sekolah saat penelitian dilakukan. Sebanyak 92.4% atlet mengaku mengonsumsi suplemen dalam satu tahun terakhir. Dilihat dari kategori olahraga, tidak semua atlet dari kategori olahraga sedang dan berat mengonsumsi suplemen. Namun, atlet dari kategori olahraga ringan dan berat sekali semuanya mengonsumsi suplemen. Suplemen vitamin, mineral, dan fitonutrisi dalam bentuk tablet merupakan jenis dan bentuk suplemen yang paling banyak dikonsumsi. Sebanyak 89% dari atlet mengonsumsi suplemen setiap hari. Alasan utama atlet mengonsumsi suplemen adalah untuk memenuhi kebutuhan gizi. Pelatih merupakan sumber infomasi tentang suplemen yang paling banyak dipilih oleh atlet. Lebih dari 50% atlet mendapatkan suplemen dengan cara diberi. Hubungan antara jenis kelamin dengan konsumsi suplemen serta hubungan antara kategori olahraga dan konsumsi suplemen menunjukkan hubungan yang tidak signifikan. Kategori olahraga dan jumlah suplemen yang dikonsumsi menunjukkan hubungan positif signifikan (p<0.05)., The objective of this study was to investigate used supplement among SMA Ragunan Jakarta athletes. This was a cross sectional study. Subjects were the students of Ragunan high school who were willing to join the study and were at school when the study was conducted. Of these athletes, 92.4% used supplement in last one year. By category of sport, not all category from moderate and heavy sport used supplement. All atlhetes from light and heavy sport category were found used supplement. The most popular supplement were vitamin, mineral, and phytonutrition in tablet form. Of these athletes, 89% consumed supplement everyday. Moreover, the main reason for supplementation was to meet a nutrition requirement. Coach was the most chosen by athletes for a source information about supplement. More than half of athletes got supplement for free from any sources . The relationship between gender and supplement used had no significant correlation. No relationship found between category of sport and supplement used. There is a significant correlation between category of sport and number of supplement used (p<0.05).
Keyword: atlet, remaja, SMA Ragunan, suplemen

Judul: Bifurkasi Hopf pada siklus bisnis IS-LM tanpa dan dengan waktu tunda
Abstrak: One of business cycle models in dynamical economics is the IS-LM business cycle model with time delay, where the time delay lies in stock capital variables. It is a time delay between the existence of stock capital and the time to get ready to invest. In a model without time delay, changing the parameter of investment rate on income could affect the system stability. On the other hand, in a model with time delay, there exists critical time delay changing the system stability. This shows limit cycle, which can be concluded that Hopf bifurcation occurs
Keyword: Bogor Agricultural University (IPB), time delay, Hopf bifurcation, business cycle model