Judul: Peran media massa terhadap kebiasaan jajan Siswa Sekolah Dasar di Kota dan Kabupaten Bogor
Abstrak: In health terms, childhood are particularty important times ·of life. Eating habits can become established even earlier in childhood. Several environmental factors influence adolescents' food habits and mass media is thought to be one of these factors. The purpose of these study was to analyze role of mass media with snacking behavior for elementary student in Begor City and Begor District. Data were collected from 72 elementary student from 12 school in Begor City and District. Data collected by purposive sampling. Deskriptive analyses were used ti describe individual, social-economic characteristic, kind of mass media, role of mass media, and snacking habits. Correlation analyses were used to examine associations between role of mass media and snacking· habits. There was significant positive associations between age, information score, and motivation score with frequency of snack consumption. There was negative associations between information score and motivation score with amount of consumption, but between age and pocket-money with amount of consumption and pocket-money with frequency of snacking not associated.
Keyword: Age-school, Mass media

Judul: Kebiasaan Jajan Anak Sekolah Dasar di SD 036, SD 070 dan SD Muhammadiyah 5 Kota Pekanbaru
Abstrak: The purpose of this study was to examine the habits of eating snacks among the school children at SD 036, SD 070 and SD Muhammadiyah 5 in the town of Pekanbaru. This was a cross sectional study with the subjects of 108 children in Grades 4 and 5(10-12 years). The data on the habit of eating snacks were collected by using a 2x24 hour Food Recall and Food Frequency (FFQ), processed using Nutrisurvey, Microsoft Excel 2007 and analyzed using the Statistical Program for Social Science (SPSS) 16.0 for Windows. The Spearman correlation results indicated there was a significant positive relationship between parent’s (mother and father) education and the number of major foods and beverages, while on the food frequency mother’s education had a significant and positive correlation with the main meal snacks and beverages. The Spearman correlation results also showed a significant negative relationship between mother’s education and the habit of eating snacks (number of snack types and frequency) and between father and mother's education and fruit snack habit (number of snack types and frequency). Further, the Spearman correlation results indicated that there was a significant positive relationship between family income and the habit of eating snacks (the number of minor snack types and snack frequency), and on the fruit snacks there was a significant positive correlation between family income and the number of snack types, while on the beverage snacks there was a significant negative correlation between the amount of snack pocket money and the snack habit (number of snack types and frequency). The amount of snack pocket money and the number of major food snack types were positively and significantly related, and on beverage snacks there was also a positive and significant correlation between the amount of snack pocket money and the snack habit (number of snack types and frequency).
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Judul: Optimization of Thermal Efficiency of Organic Rankine Cycle  System (ORC) Using Working Fluid Variation based on Simulation
Abstrak: Sipahutar (2019) telah melakukan simulasi sistem Organic Rankine Cycle menggunakan software Cycle Tempo. Simulasi ini dilakukan untuk mengetahui peforma kerja sistem ORC dengan variasi fluida kerja diantaranya R-134a, R-32, R- 407A, dan R-422C. Untuk meningkatkan peforma kerja sistem ORC, maka pada penelitian ini dilakukan optimasi dengan modifikasi parameter perlakuan pada suhu keluaran kondensor dan evaporator. Parameter yang disimulasikan adalah suhu keluar kondensor dimulai dari suhu 20 °C sampai 52 °C tiap kenaikan 0,5 °C, sedangkan pada suhu keluar evaporator disimulasikan dari suhu 71 °C sampai 85 °C tiap kenaikan 0,5 °C. Hasil simulasi ORC menunjukkan bahwa R-422C adalah fluida kerja yang optimum diantara fluida kerja lainnya dengan efisiensi termal yang dihasilkan sebesar 13,68%. Efisiensi tersebut didapat pada suhu keluar kondensor 51,5 °C dan suhu keluar evaporator 73 °C. Hal ini juga ditunjukkan oleh nilai daya yang dibutuhkan pompa (Win) yang lebih kecil dan kalor yang dibutuhkan oleh evaporator (Qin) juga lebih kecil dibandingkan dengan fluida kerja lainnya, sehingga kalor buang (Qout) yang dihasilkan minimum dan efisiensi termal bernilai lebih tinggi., Sipahutar (2019) has simulated Organic Rankine Cycle system using Cycle Tempo software. This simulation was conducted to determine the working performance of ORC system with variations of working fluid including R-134a, R-32, R-407A, and R-422C. To improve the performance of ORC system work, then in this study was done optimization with modification of treatment parameters at the temperature of condenser exit and evaporator exit. The simulated parameter is the condenser exit temperature starting from 20 °C to 52 °C per increase of 0,5 °C, while in the exit temperature the evaporator is simulated from 71 °C to 85 °C per increase of 0,5 °C. ORC simulation results showed that R-422C is an optimum working fluid among other working fluids with a resulting thermal efficiency of 13,68%. The efficiency is obtained at the exit temperature of the condenser 51,5 °C and the evaporator exit temperature of 73 °C. It is also indicated by the required power value of the pump (Win) is smaller and the heat required by the evaporator (Qin) is also smaller compared to other working fluids, so that the resulting minimum exhaust heat (Qout) and thermal efficiency are of higher value.
Keyword: fluid properties, optimization, ORC, simulation, thermal efficiency