Judul: Rancang Bangun Sistem Kendali untuk Kendaraan Sprayer Tanpa Awak Berbasis Jaringan.
Abstrak: Sprayer is commonly used in agro-chemical aplication in form of a mist. However, the exposure of agrochemical to operator on operating sprayer potentially causing risk to operator health. The objective of this research was to design a web-based control system for unmanned sprayer in order to improved health aspect of operator. Mini electric car was modified into web-based controlled was used as model for this research. Maximum range of radio control was 55 m and maximum range of web-based control (Wifi) was 110 m. Therefore, web based control was chosen because it has wider range. The average forward speed of model was 31.04 cm/s with 1% of slip for left rear wheel and 2% of slip for right rear wheel. The average turning radius of model was 210.4 cm for turning right and 290.9 cm for turning left. Controlling test conducted at straight path, turn right, and turn left with 3 kinds of different camera angle i.e. 72o, 77°, and 90°. According to data analysis result by using ANOVA could be concluded that camera angle significantly affected on controlling straight and left turn, but didn’t significantly affected on controlling turn right. The difference in significancy was due to the model just using motor in the right rear wheel for moving so the model tends to moved towards the left.
Keyword: agricultural chemicals, operator health, unmanned sprayer, web based control

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: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology