Judul: Simulasi Proses Pengeringan Jagung Pipilan dengan Mesin Pengering Surya Tipe Efek Rumah Kaca (ERK)-Hybrid dengan Wadah Silinder
Abstrak: Generally uniformity of moisture content was difficult to be reached due to un-mixed product during drying process. A study on performance of hybrid-green house effect (GHE) solar dryer with rotary drum chamber for shelled corn drying has been conducted. The objectives of this research were: to evaluate performance of hybrid-GHE solar dryer with cylinder type, to develop model to predict temperature, relative of humidity, and decreasing of shelled corn moisture content and to validate the model which developed by the experimental data. The model was constructed based on heat and mass balance. The models were solved by Euler’s finite difference method. Three experiments have been conducted and the results showed that the range of room temperature and relative hummidity were 34.0-41.0 °C and 60.2-76%, respectively. Based on this condition, 1114.1-1304.3 kg mass of shelled corn with the initial moisture content 22.28-24.87% wb. could be dried until to 15.92-17.58% wb. in 8-11 hours. By rotating the cylinder 15 minutes per hour, difference of inside and outside temperature of shelled corn layer was 0-9.8°C and moisture content was 0-2.3% wb. The drying capacity was 118.57-161.76 kg/h. Spesific energy consumption and main cost were 6.03-10.13 MJ/kg and 75.89-124.37 Rupiah/kg, respectively. Total efficiency with solar iradiation and without solar iradiation were 19.88-39.15% and 22.51-46.06%, respectively. The models that had developed has already explain the experiment data. Coefficient of determinant (COD) of model with experiment data for room temperature, relative of humidity, grain temperature, water tank temperature, and moisture content were 0.74, 0.09, 0.35, 0.91 and 0.98, respectively. The absolute percentage deviation (APD) were 1.29%, 5.89%, 1.79%, 3.5% and 0.86%. Simulation for rotating cylinder showed that by continuous rotating had the highest influence for uniformity of temperature and moisture content. The result showed that this treatment had smallest difference of inside and outside temperature and moisture content were 0.05-1.78°C and 0.14-0.56% wb. respectively. Simulation for input changing showed that by using higher mass flow rate was 0.8 kg/second had the best influence for uniformity of temperature. The result showed that this treatment had smallest difference of inside and outside temperature was 0.31-7.81°C and the APD was 3.82%. And by adding 10% iradiation input had the highest influence for uniformity of moisture content. The result showed that this treatment had smallest difference of inside and outside moisture content was 0.14-2.94% wb. and the APD was 1.09%.
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Judul: Uji Performansi Pengering Efek Rumah Kaca (ERK)-Hybrid Tipe Rak Berputar untuk Pengeringan Sawut Ubi Jalar (Ipomoea batatas L.)
Abstrak: Rotating rack green house effect (GHE) solar dryer is one type of dryer with the source of energy from solar and biomass energy for drying of agricultural products on the racks that can be rotated verticaly. The capacity of the drying chamber is 48 kg of chopped sweet potatoes. The objective of this study is to test the performance of the hybrid green house effect dryer for drying chopped sweet potatoes and to define modeling of heat transfer in the drying chamber. There are three experiments of drying: the first is without products, the second and the third are drying products without rotating rack and implement the rotating rack 45° every 60 minutes, respectively. The results of chopped sweet potatoes drying show that drying temperature on the dryer chamber ranged between 31.6-61.5°C. To reduce moisture content from around 71.3 %wb to 9.96 %wb for Experiment 2 and to reduce moisture content of 72.76 %wb to 9.5 %wb for Experiment 3, it is needed 14.5 hours and 13.5 hour, respectively. The specific energy consumption of both experiments were 42.83 MJ/kg of moisture evaporated and 35.15 MJ/kg of moisture evaporated and the drying efficiency of 5.78 % and 7.47%, respectively. Based on the performance test, it can be concluded that rotating rack dryer shows better performance than that of without rotating rack.
Keyword: solar dryer, biomass, Chopped sweet potatoes

Judul: Balantidiosis disentri dalam zoonosis
Abstrak: Balantiosis merupakan suatu penyakit pada manusia dan ababi yang disebabkan oleh Balantidium coli. Penyakit ini pertama kali diamati oleh Kalmsten pada tahun 1857 pada pasien yang mendrita diare, sedang balantidiosis pada babi pertama kali dilaporkan oleh Leukart pada tahun 1862. Parasit ini merupakan protozoa terbesar yang berada pada usus manusia dan babi dan salah satu Giliata yang patogen.
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