· Professor, University of California, Berkeley2020–
· Professor, University of California, San Francisco2017–
· Physicist Faculty Scientist, Berkeley Lab2014–
· Associate Professor, University of California, San Francisco2012–2017
· Assistant Professor, University of California, San Francisco2006–2012
· Lecturer Part-Time Faculty, University of California, Los Angeles2003–2003
· Research Specialist, University of California, San Francisco2003–2006
· Lecturer Part-Time Faculty, California State University, Northridge2002–2002
· Lecturer Part-Time Faculty, El Camino College2002–2002
· Postgraduate Researcher, University of California, Los Angeles2002–2003
· M.S. (2001) & Ph.D. (2002), Physics/Astroparticle Physics, University of California, Los Angeles1999–2002
· Ph.D. Program (not completed), Physics/Medical Physics, University of California, Irvine1998–1999
· Founding Member, Neowiz1997–1997
· M.S. (1997), Physics/Space Plasmas, University of Alabama in Huntsville1995–1998
· B.S. (1995), Physics/Space Physics, Korea Advanced Institute of Science and Technology1992–1995