윤석현 교수

Simultaneous PET/MRI was possible with a multichannel SiPM-based PET scanner, with no radiofrequency interference on PET signals or images and only slight degradation of the MRI scans.

This paper describes two novel time-to-digital converter (TDC) architectures. The first is a dual-phase tapped-delay-line (TDL) TDC architecture that allows us to minimize the clock skew problem that causes the highly nonlinear characteristics of the TDC. The second is a pipelined on-the-fly calibration architecture that continuously compensates the nonlinearity and calibrates the fine times using the most up-to-date bin widths without additional dead time. The two architectures were combined an

These results indicate that it is possible to develop a PET system using a promising semiconductor photosensor, which yielded reasonable PET performance in phantom and animal studies.

We developed a multiparametric imager with high physical performance and good system stability and demonstrated its feasibility for small-animal experiments, suggesting its usefulness for investigating in vivo molecular interactions of metabolites, and cross-validation studies of both PET and MRI.

The developed MR-compatible PET insert is designed for insertion into a narrow-bore magnetic resonance imaging scanner, and it provides excellent imaging performance for PET/MR preclinical studies.

Urinary tract infection (UTI) is one of the most common complications after radical cystectomy and orthotopic neobladder reconstruction. This study investigated the incidence and implicated pathogen of febrile UTI after ileal neobladder reconstruction and identify clinical and urodynamic parameters associated with febrile UTI. From January 2001 to May 2015, 236 patients who underwent radical cystectomy and ileal neobladder were included in this study. Fifty-five episodes of febrile UTI were iden

PURPOSE: We investigated how the symptoms of interstitial cystitis/painful bladder syndrome (IC/PBS) are correlated with the sexual activity of these patients. MATERIALS AND METHODS: A total of 87 patients were included in this study; 18 patients were diagnosed with IC and the other 69 had PBS. The diagnosis was made on the basis of the concept of IC/PBS proposed by the ICS in 2002. Patients were asked to fill in a Bristol female lower urinary tract symptom questionnaire, and symptoms were rated

This paper describes a block detector multiplexing technique that simplifies the extension of axial length or ring radius without employing extra data acquisition channels. The proposed multiplexing circuit (bipolar multiplexing) multiplexes block detectors by encoding the position-related signal outputs with different combinations of polarity. Accordingly, it is possible to distinguish the detectors using a shared readout channel. This method was evaluated by assessing one to 16 block detectors

This research shows optimization approaches to protein folding. The protein folding problem is to predict the compact three dimensional structure of a protein based on its amino acid sequence. This research focuses on ab-initio mathematical models to find provably optimal solutions to the 2D HP-lattice protein folding model.\n\nWe built two integer programming (IP) models and five constraint programming (CP) models. All the models give provably optimal solutions. We also developed some CP techni

Raman scattering, especially electronic Raman scattering, is brie°y reviewed and introduced as a research tool for studying strongly correlated electron systems. Since the Raman scattering process directly couples to electronic, lattice, and spin degrees of freedom, it is especially suited for probing excitations of various origins and the correlations among them. Through Raman scattering measurements, one can get energy, lifetime, and symmetry information on the excitations. The results of Ra

SB exhibited anti-inflammatory effects comparable to those of PPS in the HCl-induced chemical cystitis model.

2389 Objectives An effective way to reduce the complexity of a PET readout system is multiplexing of the detector block analog signals before digitization. Conventional multiplexing methods using photomultiplier tubes (PMT) are not suitable for silicon photomultipliers (SiPM) because SiPM have different output impedance levels and noise characteristics from PMT. Therefore, we have devised new analog signal multiplexing methods for SiPM (simple and extended bipolar multiplexing) and verified the

We review resonant Raman scattering studies of GaAs1−xNx, where nitrogen impurities are spatially localized in the host GaAs. The conventional intensity resonance could provide symmetry information regarding nitrogen-induced states, such as E+, which turned out to have significant components of an L and an X character, in addition to a Γ character. We also observed the rather unusual and distinctive phonon linewidth resonance due to spatially localized intermediate states that originated from a