This is Pingyu Liu, I am a physicist. After receiving my Ph.D. degree in physics, I have been in aerospace, medical and national security fields.
I have experience ranging from academics to industry, from physics to aerospace, from image processing to transducer design, and from healthcare to national security. I was an invited speaker at international conferences, and I was invited to be an NIH grant review panelist.
My main experience is the following:
Allied-Signal Aerospace Co., Engineer III. Main achievements: Stress/Strain finite element analysis, Transducer circuit optimization, Linear/nonlinear optimization program design.
Indiana University School of Medicine, Associate Professor of Radiology. Main achievements: Photoacoustic imaging theory development, Optical tomography, Cardiac CT, Thermal-enhanced MRI, Image reconstruction teaching, Radiation physics and Statistics teaching.
Acuson Corporation, Image Analysis Engineer IV. Main achievements: Background Noise Supreession project, Digital filter design and analysis for medical ultrasound systems. 
Stanford University, Department of Radiation Oncology, Medical Physicist. Main achievements: Introduced nonlinear deffusion filtering algorithm for image segmentation in oncology treatment planning, Provided medical physicist services in 3 radiation oncology clinics including 150+ IMRT planning plus QA, Brachytherapy planning/and handling, Simulator QA,
Varian 600 and 2100 Linac QA, Radioisotope management/radiation safety.


Rapiscan Systems, High Energy Inspection Corp., Senior Staff Scientist.

Main achievements: X-ray scattering, radiation dose modeling and calculation, Image processing algorithm development for target recognition, Airport Security System Design & Evaluation, Radiation Safety Survey and Report for Company and new Product, Drafted and finalized FDA report of a new radiation product per 21 CFR 1002, Drafted a new and inexpensive way to detect atomic bombs hidden in cargoes.
Partial list of my patents and publications are the following:
PATENTS (selected):
1. Liu, P. " Pressure correction for temperature transient environment for R-C type digital pressure transducers ".
2. Liu, P. "Apparatus and method for constructing computed tomography image slices of an object undergoing cyclic motion." ( U.S. patent 6233478, May 15, 2001 )
PUBLICATIONS (selected):
1. Liu P.Y. and Kruger R.A. Comments on 'Quantum noise in detectors'. Medical Physics, 4(11):561,1984.
2. Liu P.Y., Kruger R.A., Nelson J.A., Miller F.J.,Osborn A. and Wojtowycz M. Digital angiography: matched filtration versus mask-mode subtraction. Radiology, 154(1):217-220,1985.
3. Liu P. Analyses and modeling of quartz capacitive pressure sensors. 1991 Allied-Signal Technical Exchange Conference on Sensors, Tucson, AZ, March 19-20, 1991.
4. Liu P. Theoretical analysis of electromagnetic wave scattering for a photo-optic smoke detection system. Allied-Signal Aerospace Company, AiResearch Tucson Division Technical Report 91-04922, November 1991.
5. Liu P and Kruger RA. Solution to the time-dependent photon transport equation. Proc. SPIE 2077:130-141(1993).
6. Liu P. A new phase function to describe optical scattering within biological tissues. Proc. SPIE 2135:105-116(1994).
7. Liu P and Kruger RA. New approach to the 'forward problem' of optical diffusion tomography of turbid media. Proc. SPIE. 2135:227-238(1994).
8. Liu P. A new phase function approximating to Mie scattering for radiative transport equations. Physics in Medicine and Biology 39:1025-1036(1994).
9. Liu P and Kruger RA. Photo-acoustic energy conversion efficiency for a simplified absorber model. Proc. SPIE 2134A:89-92(1994).
10. Liu P and Kruger RA. A semi-analytical approach to pulsed light propagation in scattering and absorbing media. Optical Engineering 33:2783-2799(1994).
11. Liu P, Kruger RA, Appledorn CR and Fang YR. Simulation of photoacoustic signal production in human breast phantom at 1064 nm. Proc. SPIE 2708:312-322(1996).
12. Liu P, Kruger RA, Fang YR and Appledorn CR. Photoacoustic methods of measuring SAR (Specific Absorption Rate) in turbid environment. (Invited by the 9th International Conference on Photoacoustic and Photothermal Phenomena, 1996)
13. Liu P. Image reconstruction from photoacoustic pressure signals. Proc. SPIE 2681:285-296(1996).
14. Liu P. The P-transform and photoacoustic image reconstruction. Physics in Medicine and Biology. 43:667-674(1998).
15. Liu P, Ge W, and Boyer A. Unified imaging theory for x-ray and acoustic computerized tomography. Proc. SPIE 5562:76-76(2004).