The Optimization of Collimator Material and In Vivo Testing Dosimetry of Boron Neutron Capture Therapy (BNCT) on Radial Piercing Beam Port Kartini Nuclear Reactor by Monte Carlo N-Particle Extended (MCNPX) Simulation Method - Sardjono, Yohannes (Fakultas Sains dan Matematika Universitas Kristen Satya Wacana, 2018)