Judul: Design Of Variable Rate Fertilizer Applicator Frame
Abstrak: Frame for variable rate fertilizer applicator has been developed in order to mount the unit with the transplanter. The purpose of this study is to design and analyze its performance in paddy fields. The design of the frame unit was carried out with Computer Aided Design Software based on data obtained through the formulation and refinement of the idea of design and analysis of strength of material. The main function of the frame is to support hopper unit which has 120 kg weight. Variable rate fertilizer applicator unit consisted of four fertilizer hoppers, each equipped with a variable metering device which powered by a DC electric motor. Once designed, then prototype was built and its performance was tested in the experimental paddy field of the Mechanical and Biosystem Engineering Department, Faculty of Agricultural Technology, Bogor Agricultural University. The results of functional test and field performance test showed the designed prototype was function properly and was able to support the load generated by four filled hoppers full of fertilizer (120 kg). Average sinkage on an empty hopper was 21.60 cm, while the average sinkage on filled hopper was 24.74 cm. The average slip for empty hopper was 16.3% while the average slip for filled hopper was 20.2%.
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Judul: Desain dan Pengujian Prototipe Mesin Pemupuk Butiran Laju Variabel Empat Baris untuk Pertanian Presisi
Abstrak: In conventional method, fertilizer is applied at a uniform dosage for all location of a field. However, each location within the field needs different amount of fertilizer according to the soil nutrient content and growth condition of crop. For that purpose, it is important to develop a fertilizer applicator that allows a prescribe rate of fertilizer to be applied at each location within the field, based on recommended dose. The objectives of this research were: 1) to design digital metering system to control the application rate of a variable rate granular fertilizer applicator, 2) to develop a prototype of 4 rows granular fertilizer applicator, that can provide prescribe application rate automatically, and 3) to obtain field performance data of the prototype. A prototype of the variable rate granular fertilizer applicator was designed and constructed.The metering device consisted of two fluted wheel type of rotors which was driven by controlled DC-motor. To provide a prescribe rate of fertilizer, a control system based on microcontroller DT-AVR ATmega128L modul was developed and set to control the speed of the rotor. The prototype then was tested using three types of granular fertilizers (Urea, SP-36 and NPK), on stationary test and field tests. The stationary test result showed that the PID controller could control and provided a proportional correlation between application rate and rotor speed. The field performance test result showed that the designed prototype could provide a proper predetermined application rate of fertilizers precisely. The average deviations of the application rate for 50, 100, 150, 200, 250 kg/ha dose of Urea were -1.67 , 3.33, 0.28, 2.71 and 1.33 % respectively. For SP-36 were -21.67, -5.42, -2.47, -2.71, and -1.67 %. respectively. For NPK were -18.33, -4.17, -4.17, -3.75 and -2.33 % respectively.
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Judul: Psittacosis Sebagai Zoonosis Penting Yang Berasal Dari Burung
Abstrak: Psittacosis atau ornithosis adalah penyakit menular dari burung kepada manusia. Agens penyebab psittacosis termasuk ke dalam virus psittacosis-lymphogranuloma venereum group yang disebut Chlamydia psittaci. C. psittaci hanya dapat berkembang biak di dalam jaringan hidup tetapi peka terhadap antibiotik. Penyebaran penyakit ini sangat luas, terdapat hampir di seluruh dunia. Di Indonesia penyakit ini belum pernah di diagnosa, tetapi mengingat terdapat demikian banyaknya jenis burung maka diperkirakan psittacosis ini sudah ada. Kasus pada manusia pertamakali ditemukan oleh Ritter pada tahun 1879, di Eropa. Waktu itu dikenal sebagai pneumotyphus. Chlamydia psittaci tidak hanya sebagai penyebab infeksi pada burung, juga bisa menyebabkan infeksi pada mamalia diantaranya sapi, kerbau, kambing, domba, babi dan kucing. Pada kucing dikenal sebagai feline pneumonitis. Pada domba atau kambing mengakibatkan enzootic abortion. Pada burung, kalkun merupakan unggas paling rentan diikuti oleh burung psittacine dan burung lain di luar famili psittacidae. Virulensinyapun berbeda-beda. Yang berasal dari kalkun bervirulensi tinggi, sedangkan yang berasal dari burung merpati bisa bervirulensi tinggi bisa juga bervirulensi rendah. Penularan terjadi melalui kontak langsung maupun ti- dak langsung. Penularan melalui telur tidak terjadi. Umumnya penyakit ini memperlihatkan gejala klinis berupa deman, lesu, lemah, anorexia, kurus, diarrhea ber- warna kekuningan, discharge dari mata dan hidung, conjunc- tivitis. Gejala khas pada kalkun adalah istirahat dengan sternum sebagai dasarnya, karena adanya tekanan dari bagian perut yang sakit. Sedangkan pada manusia memperlihatkan adanya demam, kadang-kadang merasa dingin, lesu, sakit kepala yang hebat, sakit pada bagian belakang badan dan photophobia…dst
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