Judul: Rancangbangun Sistem Pengendalian Tuas Pengendali Implemen untuk Otomatisasi Traktor.
Abstrak: Modern farming is indicated by the use of agricultural tools and machines that substitute human labor. In the process of land preparation, planting, plant preservation, and harvesting, the use of human labor has been reduced and replaced by agricultural machines. The objective of this research was to modify the implement control system for automatic land plowing. The design was using a sprocket-chain mechanism that was connected to the control lever, there after the lever could be moved in back and forward directions. The sprocket was rotated by a DC motor that was controlled by a micro controller passing through H-Bridge device, thereby the lever could be ascend and descend easily by changing the direction of DC motor’s rotation. A potentiometer had been used to measure the rotation angle as the output of the lever position. The scale change at the potentiometer was converted to a digital data by the micro controller and would be used as a feedback. At the field performance test, the prototype was tested to control the depth of a disk plow in a tillage operation using a 4-wheel tractor. The test result showed that, the control system could control the plowing depth in the average of 19 cm at the 350 ADC setting, and 13 cm at 450 ADC setting.
Keyword: design, implement, control, smart tractor

Judul: Rancang Bangun Sistem Kendali Otomatis Traktor Roda Empat
Abstrak: Automation of four-wheel-drive tractor is an alternative of solution to the lack of manpower operator in the future. With the automated control system, the tractors can be operated without interruption as long as the fuel still available, workload and fatigue experienced by operators can be reduced, can also improve the accuracy of productivity, and reduce the possibility of overlapping while processing of land. In this current research, control of tractor is limited to the operation of acceleration pedal, clutch system, and steering systems. The main components of the control system consists of a DC-motor as a driving power transmission system that connects actuators, and sensors that monitor the position of the movement of the actuator position. These components were designed to work according to the steps of manually operation. Data research showed the system to function properly. Speed of the clutch lever operation until it reaches the point of maximum point is one second, and the release rate to the point of minimum pressure is two seconds. Average rotary speed of steering wheel to deflect to the right is the 7.40°/s, and for a left turn is 13.16°/s. Acceleration lever presses speed is 17.91 cm/s and the speed of release is 20.99 cm/s.
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Judul: Nisbah Kelamin Ikan Pelangi Iriatherina Werneri Pada Perbedaan Suhu Pemeliharaan
Abstrak: Ikan pelangi Iriatherina werneri merupakan ikan hias air tawar dari famili Melanotaenidae (Rainbowfishes) yang ditemukan di Papua. Ikan pelangi (Iriatherina werneri) jantan memiliki warna dan bentuk sirip yang indah, serta bernilai ekonomi lebih tinggi dibandingkan ikan betina. Penelitian ini dilakukan untuk mengevaluasi pengaruh perbedaan suhu pemeliharaan terhadap nisbah kelamin ikan pelangi Iriatherina werneri dalam wadah budidaya, kelangsungan hidup, derajat penetasan dan pertumbuhannya. Penelitian menggunakan Rancangan Acak Lengkap dengan perlakuan suhu (28-30 ºC, 30-32 ºC, dan suhu ruang) masing-masing dengan 5 ulangan. Perlakuan suhu diberikan mulai dari fase telur sampai 60 hari pemeliharaan. Hasil penelitian menunjukkan suhu mempengaruhi nisbah kelamin pada ikan pelangi (P<0,05). Persentase jantan pada perlakuan suhu 30-32 ºC lebih tinggi, yaitu 73,3% dibandingkan dengan perlakuan suhu 28-30 ºC sebesar 56,7%, sedangkan pada perlakuan suhu ruang menghasilkan 30% ikan jantan. Pada perlakuan suhu 28-30 ºC dan 30-32 ºC menghasilkan persentase ikan jantan dua kali lipat lebih tinggi yaitu sebesar 56,7% dan 73,3% dibandingkan dengan pemeliharaan pada suhu ruang sebesar 30%. Kelangsungan hidup pada penelitian ini berkisar antara 23,9% sampai 40,3%, derajat penetasan berkisar antara 43,4% sampai 47,2% dan pertumbuhan ikan pelangi pada perlakuan pemeliharaan dengan suhu 28-30 ºC menunjukkan kecenderungan pertumbuhan yang lebih tinggi dibanding perlakuan suhu 30-32 ºC dan suhu ruang, yaitu mencapai 23,4 mm.
Keyword: Iriatherina werneri, jantan, suhu, nisbah kelamin