Judul: Rancang Bangun dan Pengujian Unit Penyemprot pada Alat : Penyemprot Padi Tipe Balon
Abstrak: Spraying of fertilizers and pesticides on rice field is one of important maintenance activities for rice crop cultivation. Usually this activity is done in the morning because the wind conditions which allow the fertilizers or pesticides to be uniformly spread to field and to avoid drift. The activity is generally carried out manually by farmers using knapsack sprayer and the farmer had to walk between rice plant, which is laborious and can damage the planting furrow. Spraying application using tractor could not be done because of the condition of rice field, where almost field haven’t hardpan. These problems can be overcome by aerial spraying using air planes. The use of plane for spraying has some drawback such as high cost and safety related to ground condition. Another possible solution is to use a balloon equipped by control system and sprayer system for liquid fertilizer or pesticide application. Control system adopted the multi copter with flying board and for spraying systems adopted the electric sprayer. Spraying system used an electric pump for distribute the fertilizer or pesticide. Washer pump used for this prototype, the washer pump can produce a debit 1.20 l/min. The system created can do the spraying area 2.52 m2 per second equal to 0.91 ha/hour when the velocity 4.17 km/hour.
Keyword: Bogor Agricultural University (IPB), paddy sprayer, electric sprayer, balloon type sprayer, aerial spraying

Judul: Rancang Bangun Sistem Sprayer Otomatis pada Kendaraan Tanpa Awak.
Abstrak: Sprayer merupakan aplikator pestisida untuk pengendalian hama dan penyakit tumbuhan. Penelitian sebelumnya hanya merancang bangun sistem kendali kendaraan tanpa awak. Tujuan dari penelitian ini adalah merancang sprayer otomatis pada kendaraan tanpa awak untuk meringankan beban dan meningkatkan kenyamanan operator. Metode penelitian terdiri dari identifikasi masalah, perancangan sprayer otomatis dengan mikrokontroler dan sensor ultrasonik, pembuatan program, analisis kebutuhan sprayer otomatis, pengujian fungsional, dan pengujian kinerja. Hasil dari Butiran semprotan halus yang digunakan adalah berukuran 990 μm, keseragaman (Coefficient of Variation) 0.624, dan tekanan 120 kPa. Mekanisme penyemprotan digunakan delay karena ada jarak antara nozzle dan sensor ultrasonik sebesar 1.825 detik supaya semprotan tepat mengenai tanaman. Pengujian debit penyemprotan ialah 0.498 liter/menit dan waktu penyemprotan sprayer disesuaikan dengan lebar tanaman dan kecepatan maju kendaraan. Hasil untuk kapasitas lapang efektif rata-rata ialah 0.06 ha/h dan teoritis ialah 0.23 ha/h sehingga rata-rata efisiensi lapangnya sebesar 26.27%.
Keyword: automatic sprayer,, nozzle, ultrasonic sensor, unmaned vehicle

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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