• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.815-820
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• 2002

MSC as a payload of KOMPSAT-2 is an optical telescope for earth imaging on a sun-synchronous orbit. The MSC is a Ritchey-Chretien type telescope composed of hyperbolic primary and secondary mirrors with focal correcting lenses. Their relative positions should be kept aligned during imaging operation. However, the MSC is exposed to adverse thermal environment on orbit which can have some impacts on optical performance as well as structural endurance. Solar incidence can cause non-uniform temperature rise on the tube which entails unfavorable thermal distortion. Three options were proposed, which were internal shield, external mechanical shield and spacecraft maneuvering. After the trade-off studies, internal sun shield was selected as a realistic and optimal solution to minimize the effect of the solar radiation. In this paper, pros and cons are explained for the three possible choices and a design of the internal shield is discussed.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.1
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• pp.93-99
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• 2007

Purpose : The aim of this study is to consider degenerative spine disease theoretically and compare plain radiography which is a basic study for low back pain with MRI in cases of degenerative lumbar spine disease to find out whether the abnormalities agree with each other. Methods : In 4 cases of lumbar degenerative disease, we studied the relation of the abnormalities such as disc space narrowing, spinal space narrowing, loss of lordosis and osteophytes on plain radiography with those on MRI of HIVD, spinal stenosis and spondylolisthesis. Results : Many abnormalities such as disc space narrowing, spinal space narrowing, loss of lordosis, osteophytes and change of cortex & bone marrow on plain radiography suggest HIVD, spinal stenosis, spondylolysis or spondylolisthesis on MRI. Conclusion : For low back pain patients, plain radiography is a basic study in diagnosis of HIVD, spinal stenosis, spondylolysis or spondylolisthesis but MRI or CT scan is necessary to develop(build) a treatment plan like an operation.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2371-2374
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• 2010

• Proceedings of the KSMRM Conference
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• 2001.11a
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• pp.136-136
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• 2001

Purpose： Subclavian steal refers to the retrograde flow of blood in a vertebral artery that supplies t ipsilateral shoulder and arm caused by proximal subclavian artery stenosis or occlusion. T purpose of this exhibit is to demonstrate MR findings of subclavian steal on contrast-enhanc 3D (CE 3DMRA) and 2D TOF MR angiography. Method： Four patients(men 3 and women 1, age： 28-78years) with subclavian steal obtained both CE 3DMRA and digital subtraction angiography(DSA) including subclavian arterie Sequential imaging was undertaken during first pass after double dose of Gd-DTPA (0 mM/kg) Injected by a power injector. Coronal source images were obtained with coronal D-fast low angle shot sequence(TR/TE/flip angle=3.8/l.3/35, acquisition time= 10sec/one measurement). Precontrast imaging was subtracted from enhanced images and maximu intensity projection was done. 2D time-of-flight MR angiography(2D TOF) of the carot bifurcation was added in all cases with post-saturation. All studies were review retrospectively.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.485-488
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• 2002

In order to understand and quantitatively analyze the physical phenomena and behavior of each component of mammography system during the breast imaging, we simulated mammography imaging using Monte Carlo simulation codes. MCNP4B code was used for our simulation purpose, and we investigated the effect of target material, anode angle, filtration, peak voltage and exposure on the image quality of mammograms. From the simulation results we expect that optimized operation condition of mammography system can be found.

• BMB Reports
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• v.46 no.2
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• pp.65-72
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• 2013

In situ detection of RNAs is becoming increasingly important for analysis of gene expression within and between intact cells in tissues. International genomics efforts are now cataloging patterns of RNA transcription that play roles in cell function, differentiation, and disease formation, and they are demon-strating the importance of coding and noncoding RNA transcripts in these processes. However, these techniques typically provide ensemble averages of transcription across many cells. In situ hybridization-based analysis methods complement these studies by providing information about how expression levels change between cells within normal and diseased tissues, and they provide information about the localization of transcripts within cells, which is important in understanding mechanisms of gene regulation. Multi-color, single-molecule fluorescence in situ hybridization (smFISH) is particularly useful since it enables analysis of several different transcripts simultaneously. Combining smFISH with immunofluorescent protein detection provides additional information about the association between transcription level, cellular localization, and protein expression in individual cells.

• Investigative Magnetic Resonance Imaging
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• v.24 no.3
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• pp.174-177
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• 2020

Multiple studies have established that mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) exhibits reversible diffusion restriction in the white matter, including the splenium. There have been a few previous reports of the change in fractional anisotropy (FA) of MERS cases. Herein, we report the longitudinal changes in axial and radial diffusivity (AD and RD), and FA in a 15-year-old boy patient with MERS. Our case demonstrated that a MERS lesion had a significant drop of AD in the early period and gradual recovery. On the contrary, RD did not show any significant change.

• Journal of Korean Neurosurgical Society
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• v.57 no.3
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• pp.225-228
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• 2015

Congenital dermal sinus (CDS) is a type of occult spinal dysraphism characterized by a midline skin dimple. A 12-month-old girl presented with fever and ascending quadriparesis. She had a midline skin dimple in the upper sacral area that had been discovered in her neonatal period. Imaging studies revealed a holocord intramedullary abscess and CDS. Overlooking CDS or misdiagnosing it as benign sacrococcygeal dimple may lead to catastrophic infection and cause serious neurological deficits. Therefore, further imaging work-up or consultation with a pediatric neurosurgeon is recommended following discovery of any atypical-looking dimples in the midline.

• Journal of Korean Neurosurgical Society
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• v.48 no.5
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• pp.441-444
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• 2010

Fibrous dysplasia (FD) of craniofacial structures is well documented, however, its involvement of the clivus is seldom described. We report a case of clival FD in a young man who presented with headache localized to the occipital area. The radiological studies revealed a monostotic disease confined to the clivus, with typical findings of hypo intensity on magnetic resonance images and ground-glass density on computed tomography. The diagnosis of FD was confirmed on pathological examination of specimens taken through transsphenoidal surgery. The patient showed reduction of symptoms and no change of residual lesion on follow-up imaging taken 2.5 years later after surgery. This study includes clinical aspect, radiographic appearance, differential diagnosis and treatment strategy of this rare skull base lesion.

• Journal of Biomedical Engineering Research
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• v.26 no.4
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• pp.185-191
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• 2005

In this paper, we proposed a downscaled 3D object technique using medical images for telediagnostic use. The proposed system consisted of downscaling/thresholding processes for building a downscaled 3D object and a process for obtaining 2D images at specific angles for diagnosis support. We used 80 slices of Digital Imaging and Communication in Medicine(DICOM) CT images as sample images and the platform-independent Java language for the experiment. We confirmed that the total image set size and transmission time of the original DICOM image set using a down-scaled 3D object decreased approximately $99\%\;and\;98.41\%,$ respectively. With additional studies, the proposed technique obtained from these results will become useful in supporting diagnosis for home and hospital care.