Neutron/X-ray Combined CT and Flat-Panel X-ray Source (Graduate Seminar)
|Event Date:||April 9, 2014|
|Speaker:||Dr. Hyoung-Koo Lee|
New imaging technologies for medical and industrial applications are being developed at Missouri University of Science and Technology (Missouri S&T) in Rolla MO, USA. A novel imaging system combining traditional neutron and X-ray computed tomography (NXCT) has been designed and developed. The system holds much promise for non-destructive material detection and analysis where various materials having similar atomic numbers but differing neutron cross sections or vice versa may be present within an object. The interactions of neutrons and X-ray photons with matter produce differing characteristic information, resulting in distinctly different visual images. The NXCT system utilizes neutron and X-ray imaging simultaneously without obstructing the beam geometry for each imaging mechanism, and could produce more comprehensive pictures of the structural and compositional data for a desired object. The NXCT system is expected to have numerous applications in the field of material characterization and identification in objects with a mixture of different chemical elements and isotopes. This presentation will cover an overview of the design, operation, and some initial experimental results of the NXCT system.
In addition to the NXCT system, a novel flat-panel transmission type X-ray source is being developed for both medical and industrial use. Depending on the geometry of the given situation the flat-panel X-ray source could be used in tomography, radiography or tomosynthesis. Furthermore, the unit could be used as a portable X-ray scanner or an integral part of an existing detection system. The design incorporates a field emission cathode made of ultra-nanocrystalline diamonds (UNCD) doped with nitrogen. These field emitters show great electron output at low power and can be deposited over large areas as the case with carbon nanotube “forest” (CNT) cathodes. This work includes the first generation of the UNCD based field emission array (FEA) prototype that is being manufactured in the Center of Nanoscale Materials at Argonne National Laboratory. The prototype is a 3 x 3 pixel FEA, with a pixel pitch of 500 mm. In this presentation, principles of the device, design and initial results of electron field emission will be discussed.
Hyoung Koo Lee is Associate Professor and Chair of Nuclear Engineering at Missouri S&T. He holds PhD from University of California at Berkeley (1995), MS from Seoul National University (1988), and BS (1986) from Seoul National University, Korea. Dr. Lee has over 18 years of professional experience in research, teaching, and consulting. His previous positions include: Professor, Associate Professor, Assistant Professor (Catholic University of Korea, 1995-2009), and Medical Physicist (Kangnam St. Mary’s Hospital, Korea, 1997 – 2002; St. Mary’s Hospital, Korea 1995 – 1997).
He has and continues to lead major research initiatives in nuclear engineering and biomedical engineering with over $28 million funding from a portfolio of Korean and US funding sources. The results of his research initiatives include over 110 refereed journal and conference publications, and over 100 technical presentations.
Dr. Lee has been recognized with several awards and recognition including the 2012 Young Faculty Award by DARPA, Faculty Research Award by Missouri S&T, Junior Faculty Award by Academy of Mines and Metallurgy at Missouri S&T, Minister’s Citation by Korean Government and Research Advisor Award in Medical Physics by Korean Society of Medical Physics.
He is a reviewer for 8 journals in nuclear engineering and medical imaging. He has been serving as Executive Committee of Isotope and Radiation Division for the American Nuclear Society since 2012. He also served as Advisory Committee for Korea Electrotechnology Research Institute in 2010, as Advising Expert for Korean Scientists and Engineers Network in 2009 – 2011, as Chair of Industrial Cooperation Committee for the Korean Photodynamics Association in 2006 – 2009, as Editorial Committee for the Korean Society of Medical Physics in 2000 – 2009, as Chair of Educational Committee for the Korean Society of Medical Physics in 2006, as Scientific Committee for the World Congress on Medical Physics and Biomedical Engineering in 2006, as Scientific Committee for the World Congress of Nuclear Medicine and Biology in 2006, as Finance Director for the Korean Society of Medical Physics in 2002 – 2003, and as Financial Committee for Korea-Japan Joint Meeting on Medical Physics in 2002.
Dr. Lee has given around 20 short courses and consults for the global medical imaging companies. He is a certified medical physicist in Korea, and a member of International Society for Optical Engineering, International Society for Optical Engineering, Institute of Electrical and Electronics Engineers, American Association of Physics in Medicine, International Society for Neutron Radiology, Korean Society of Medical and Biological Engineering, Korean Society of Medical and Biological Engineering, Korean Nuclear Society, and Korean Association for Radiation Protection.
New x-ray sources for imaging, detectors for radiation imaging (x-ray and neutron), design, simulation and building of radiation imaging systems (x-ray, gamma ray and neutron), quantitative imaging (such as material density extraction from radiographs), digital image processing, CT reconstruction, radiation detection and measurement, applications of radiation imaging techniques to homeland security, nuclear non-proliferation and non-destructive evaluation.
CURRENT RESEARCH PROJECTS
Dr. Lee’s specific projects include: (i) Development of New Flat-Panel X-Ray Source for Imaging; (ii) Neutron and X-Ray Combined Computed Tomography; (iii) Neutron Tomography for Non-Destructive Evaluation of Nuclear Fuels; (iv) Computer-Aided Diagnosis of Oral Lesions from Dental Images. These initiatives are currently being funded by DARPA, NRC, Idaho National Laboratory and industry.