Rancang Bangun Sistem Pengamatan Gerak Brown dan Pengukuran Koefisien Difusi pada Microbead Polystyrene (1 μm, 3 μ Μm dan 5 μm) Terlapisi Nanogold Particle (AuNPs) dengan Bantuan Machine Learning = Machine Learning Based System Design for Observing the Brownian Motion of 1 μm, 3 μm and 5 μm Polystyrene Microbeads Synthesized with Nanogold Particles and Calculating its Diffusion Coefficient