Judul: Body Image of Adolescent Girls at High School Level in  East Nusa Tenggara
Abstrak: Perubahan bentuk tubuh menjadikan remaja lebih memerhatikan bentuk tubuh sehingga tidak sedikit remaja yang memiliki body image negatif. Penelitian ini bertujuan menganalisis hubungan pengetahuan gizi dan karakteristik subjek dengan body image pada remaja putri tingkat sekolah menengah atas di Nusa Tenggara Timur tahun 2019. Desain studi yang digunakan berupa cross sectional study dengan jumlah subjek 900 orang. Hasil penelitian menunjukan usia subjek berada pada rentang 16–22 tahun. Hasil penelitian status gizi subjek menunjukan sebagian besar remaja putri memiliki status gizi normal (72,3%) dengan body image positif (61,0%). Penggunaan media massa sebagian besar remaja putri tergolong lama (58,9%). Uang saku yang dimiliki remaja putri sebagian besar ≤ Rp15.000,00 per hari (91,0%). Sebagian besar remaja putri memiliki pengetahuan gizi yang tergolong sedang (71,9%). Status gizi berhubungan signifikan dengan body image (p<0,05). Namun, tidak terdapat hubungan signifikan antara media massa, uang saku, dan pengetahuan gizi dengan body image (p>0,05). Kata kunci: body image, pengetahuan gizi, remaja putri, status gizi, Changes in body shape are generating negative body image in a lot of adolescent girls, mainly because they pay more attention to their body shape. This study aims to analyze the correlation of nutritional knowledge and subject characteristics with the body image of adolescent girls at the high school level in East Nusa Tenggara 2019. The study design used was a cross-sectional study with 900 subjects. The results showed that the age of the subjects was in the range of 16–22 years old. The results of this study showed most subjects have normal nutritional status (72.3%) with positive body image (61.0%). The duration of mass media usage for adolescent girls is mostly long (58.9%). Most of the allowance owned by adolescent girls is IDR 15.000,00 a day (91.0%). Most adolescent girls had middle nutritional knowledge (71.9%). Nutritional status has a significant correlation with body image (p<0.05). However, there was no significant correlation between mass media, pocket money, and nutritional knowledge with body image (p>0.05). Keywords: adolescent girls, body image, nutritional knowledge, nutritional status
Keyword: adolescent girls, body image, nutritional knowledge, nutritional status

Judul: Correlation Between Body Image, Breakfast and Snacking Habit with Nutritional Status of Female Adolescents
Abstrak: Rasa tidak puas pada bentuk tubuh bagi remaja seringkali berdampak pada kebiasaan makan sehingga menunda dan/atau melewatkan waktu makan. Oleh karena itu penelitian ini bertujuan untuk menganalisis hubungan antara body image, kebiasaan sarapan, dan jajan dengan status gizi remaja putri SMA Negeri 33 Jakarta. Desain penelitian ini adalah cross sectional study dengan subyek berjumlah 62 orang dipilih secara purposive sampling, terdiri dari 31 subyek dengan status gizi lebih dan 31 subyek dengan status gizi normal. Pengumpulan data dilakukan melalui google form dan wawancara melalui telepon. Hasil penelitian menunjukkan bahwa subyek berstatus gizi lebih yang memiliki body image negatif (93,5%) adalah signifikan (p<0,05) lebih banyak daripada yang berstatus gizi normal (77,4%). Kebiasaan atau frekuensi sarapan dan jajan subyek berstatus gizi lebih masing-masing tidak berbeda signifikan (p>0,05) dengan yang berstatus gizi normal. Berdasarkan hasil uji korelasi menunjukkan bahwa terdapat hubungan signifikan positif (p=0,001, r=0,410) antara body image dengan status gizi subyek. Hal ini berarti bahwa semakin tinggi nilai z-score IMT/U (overweight) subyek maka persepsi terhadap body image semakin negatif. Namun demikian tidak terdapat hubungan signifikan (p>0,05) antara body image dengan kebiasaan sarapan dan jajan., Dissatisfaction with body image for adolescents often has an impact on eating habits that are different from usual, causing them to delay and/or skip meals. This research aimed to analyze the correlation between body image, breakfast and snacking habits with nutritional status of female adolescents at SMA Negeri 33 Jakarta. A cross sectional study design with 62 subjects selected purposively sampling, consisting of 31 subjects with overweight nutritional status and 31 subjects with normal nutritional status. Google forms and phone interviews were used to obtain the data. The results showed that overweight subject with a negative body image (93,5%) were significantly higher (p<0,05) than those with a normal nutritional status (77,4%). Breakfast and snacking habits, estimated by its frequencies, of overweight and normal nutritional status of subject were not significantly (p>0.05) different. Based on the correlation test, there was a significant positive correlation (p= 0,001, r= 0,410) between body image and the nutritional status of the subjects. This indicated that the higher the z-score BMI/A (overweight) subject, the more negative the perception of body image. Meanwhile, there were not significant correlation (p>0.05) between body image with breakfast and snacking habits.
Keyword: ody image, breakfast habits, nutritional status, snacking habits

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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