• Korean Journal of Crystallography
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• v.4 no.2
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• pp.100-104
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• 1993

Reduced glutathione (GSH) plays a vital role in the metabolism of all cells. Glutathions, a tripeptide cowfosed of glutamic acid, cysteane, and gtycina is synthesized by two synthesized reutions. The first is catalyzed by Y-glutamylcysteine synthetase (GSH-I) and the second by glutathione synthetase (GSH-ll). The glutathione biosynthetic pathway of E. coziis mainly controlled by nonallosteric feedback inhibition of GHS-I by GSH. Determination of the three-dimensional structure of GSH-I by X-ray crystallography is necessary in order to understand the structure-function relationship at the molecular level. As the (irst step toward its structure determination, crystallization of 5. coli V-glutamylcystfine synthetase (GSH-I) has been achived using the hanging drop vapor diffusion method and capillaw method. Crystals of GSH-I have been grown from ammonium sulfate solution. The crystals grew at room temperature within 10 days to dimensions of 0.2 m x 0.2 m x 0.2 ml by hanging drop vapor diffusion method and diffracted to about 4 A resolution using synchrotron X-rays. Another crystal, grown by the capillary method to dimensions of 0.25 mm x 0.25 mm x 0.3 mm within 40 days, diffracted to about 4 A resolution using X-rays from a rotating anode.

• Journal of Biomedical Engineering Research
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• v.41 no.2
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• pp.94-100
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• 2020

The purpose of this study was to present the models for classifying the wrist X-ray images by types and for segmenting the radius automatically in each image using deep learning and to verify the learned models. The data were a total of 904 wrist X-rays with the distal radius fracture, consisting of 472 anteroposterior (AP) and 432 lateral images. The learning model was the ResNet50 model for AP/lateral image classification, and the U-Net model for segmentation of the radius. In the model for AP/lateral image classification, 100.0% was showed in precision, recall, and F1 score and area under curve (AUC) was 1.0. The model for segmentation of the radius showed an accuracy of 99.46%, a sensitivity of 89.68%, a specificity of 99.72%, and a Dice similarity coefficient of 90.05% in AP images and an accuracy of 99.37%, a sensitivity of 88.65%, a specificity of 99.69%, and a Dice similarity coefficient of 86.05% in lateral images. The model for AP/lateral classification and the segmentation model of the radius learned through deep learning showed favorable performances to expect clinical application.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.266-269
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• 2012

Over the world, the development of critical technology for the safety and security of coastal distribution based on ubiquitous computing is being processed to meet the bottom lines of governmental regulations. Currently, 3D detectors using X-rays for freight search technology are being developed concerning U-based shipping security systems. In addition to that, there are increasing needs for developing portable radiation detector to detect gamma rays nuclide. The purpose of the thesis is to suggest the research of high speed portable gamma rays detector platform to prevent disorder caused to humans and public objects.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2323-2328
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• 2012

Over the world, the development of critical technology for the safety and security of coastal distribution based on ubiquitous computing is being processed to meet the bottom lines of governmental regulations. Currently, 3D detectors using X-rays for freight search technology are being developed concerning U-based shipping security systems. In addition to that, there are increasing needs for developing portable radiation detector to detect gamma rays. The purpose of the thesis is to suggest the research of high speed portable gamma rays detector platform to prevent disorder caused to humans and public objects.

• Journal of radiological science and technology
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• v.16 no.2
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• pp.51-60
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• 1993

The $CaSO_4$ : Tm-PTFE TLDs have been prepared and their energy dependences of TL intensity to X-rays have been investigated. The dose dependence of the prepared $CaSO_4$ : Tm-PTFE TLDs is linear within the range of $100{\mu}Gy-10Gy$ for X-rays and gamma rays. The spectral peaks of TL emission spectrum are at about 350nm and 475nm. The fading rate of the main peak has been found to be about 2% for 30days when $CaSO_4$ : Tm-PTFE TLDs stored in the dark room at room temperature. The energy dependence of $CaSO_4$ : Tm-PTFE TLD has been compensated by combining the TL responses of one bare TLD and five TLDs filtered with 1.0mm Al, 0.2mm Cu, 0.5mm Cu, 1.5mm Cu, 2.0mm Pb respectively. The determined correction coefficients for filter combination are $a_0=0.078,\;a_1=-0.009,\;a_2=-0.235,\;a_3=0.588,\;a_4=0.568\;and\;a_5=0.180$ respectively. From the results of these studies, the prepared TLD badge of six dosimeter combination may be useful as a radiation dosimeter for personal and environmental monitoring.

• Polymer Science and Technology
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• v.24 no.6
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• pp.579-584
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• 2013

• Korean Journal of Ichthyology
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• v.25 no.3
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• pp.169-172
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• 2013

A malformation of the anal fin in longfin trevally, Carangoides armatus, is described and compared with normal specimens. The fish specimen is clearly shown anal fin deformity with missing of 3 spines and 6 rays. The remaining eleven anal fin rays are shorter than those in the normal specimen. The causative factors of this anomaly were discussed.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1678-1680
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• 1997

The pulsed power with the high voltage and current can be used to the fields of high speed pulses of energy in different forms such as electric current and voltage, electron beam, ion beam, x-rays, gamma rays, heat, magnetics fields, sound and shock waves. This paper is directed mainly at electrical engineers working on production and practical application of high speed pulsed power with high voltage and current.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1015-1024
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• 2019

In the medical field, X-rays are essential in the diagnosis and treatment of diseases, and the use of X-rays continues to increase with the development of imaging technology, but X-rays have the disadvantage of radiation exposure. Although lead protection tools are used in clinical practice to protect against radiation exposure, lead is classified as a heavy metal and can cause harmful reactions such as lead poisoning. Therefore, the purpose of this study is to investigate the usefulness of the shield fabricated using materials of FDM (Fused Deposition Modeling) 3D printer. In order to confirm the filament's line attenuation factor, phantoms were fabricated using PLA, XT-CF20, Wood, Glow and Brass, and CT scan was performed. And the shielding sheet of 100 × 100 × 2 mm size was modeled, the dose and shielding rate was measured by using a diagnostic X-ray generator and irradiation dose meter, and the shielding rate with lead protection tools. As a result of the experiment, the CT number of the brass was measured to be the highest, and the shielding sheet was manufactured by using the brass. As a result of confirming with the diagnostic X-ray generator, the shielding rate was increased in the shielding sheet having a thickness of 6 mm upon X-ray irradiation under the condition of 100 kV and 40 mAs. It measured by 90% or more, and confirmed that the shielding rate is higher than apron 0.25 mmPb. As a result of this study, it was confirmed that the shield fabricated by 3D printing technology showed high shielding rate in the diagnostic X-ray region. there was.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.587-589
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• 2015

We present the results from analysis of the Hilbert-Huang transform (HHT) for the 4 Hz quasi-periodic oscillations (QPO) around the black hole X-ray binary XTE J1550-564. The resultant Hilbert spectra demonstrate that the QPO is composed of a series of intermittent signals appearing occasionally. From the analysis of the HHT, we further found the distribution of the lifetimes for the intermittent oscillations and the distribution for the time intervals with no significant signal (the break time). The mean lifetime is 1.45 s and 90% of the oscillation segments have lifetimes less than 3.1 s whereas the mean break time is 0.42 s and 90% of break times are less than 0.73 s. We conclude that the intermittent feature of the QPO could be explained by the Lense-Thirring precession model and rules out interpretations of continual frequency modulation.