Judul: Rancang Bangun Sprayer dengan Kendali Nirkabel Berbasis Mikrokontroler.
Abstrak: Usaha untuk meningkatkan produksi tanaman seringkali dihadapkan dengan adanya gangguan hama dan penyakit. Pertanian lahan kering merupakan sektor yang membutuhkan banyak tenaga kerja. Manusia memiliki beberapa kekurangan dalam melakukan pekerjaan salah satunya adalah kelelahan fisik saat bekerja. Solusinya untuk mengatasi masalah tersebut dengan menggunakan robot sprayer dibidang pertanian yang dilengkapi dengan module bluetooth sebagai alat pengendalinya. Tujuan penelitian adalah merancang bangun robot sprayer yang mampu mengangkut beban tangki sprayer, dapat melaju diantara bedengan dengan kendali bluetooth dan menganalisis kinerja sprayer. Dimensi robot sprayer dengan panjang 87,5 cm, lebar 47,5 cm, dan tinggi 38 cm agar dapat menampung tangki sprayer 50 liter. Adapun kinerja robot, yaitu robot sprayer dapat melaju dengan pembebanan 50 kg di tanah dengan kecepatan sebesar 0,364 m/s dan di aspal sebesar 0,799 m/s dengan slip roda rata-rata sebesar 20,32 % ditanah dan sebesar 5,27 % di aspal. Hasil uji kinerja sprayer yang optimum diperoleh pada tekanan 3 bar (P3) yang mampu meghasilkan diameter droplet sebesar 234,02 µm, kerapatan droplet sebesar 140,68 droplet/cm2 , lebar penyemprotan efektif sebesar 88 cm, debit penyemprotan efektif sebesar 0,784 liter/menit dan jangkauan penyemprotan efektif serta jangkauan penyemprotan total masing-masing sebesar 56 cm dan 168 cm.
Keyword: bluetooth, performance of robotic, robotic, sprayer, pressure

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: 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