• Proceedings of the KSR Conference
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• 2005.11a
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• pp.382-388
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• 2005

SMSC(Seoul Metropolitan Subway Corporation) is substantially taking the core role of mass transit system in Seoul Metropolitan area. When it was built, the design had challenged to sharp curved tracks less than 250m radius considering the protection of buildings and cultural properties as well as the connection to ground roads. Such circumstances have required a certain extent of slack in track geometry and therefore led to the construction of ballasted track with wooden sleepers. However, the dynamic force from running on sharp curved track has caused the misalignment and abnormal failure of track geometry, and it has resulted in a frequent maintenance and repair works which require a lot of cost and manpower. In this paper, we present the construction case of maintenance-free track system by using of concrete sleeper and elastic rail fastening system to ensure the safety of both passengers and trains, and to contribute the effective maintenance for track facilities of SMSC.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.49-58
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• 1989

The permanent second molars, erupted about 12-13 years old, are finally erupted except wisdom teeth. Although they are likely to be excluded in the orthodontic treatment because located in the most posterior area of the dentition, about twenty percents of the orthodontic patients have abnormal occlusion of the permanent second molars, and we usually observed the malalignment of the permanent second molars in the finished case without including this teeth. These permanent second molars should be necessarily corrected by orthodontic appliances for the dynamic-normal occlusion. Moreover, according to the previously mentioned treatment philosophy, there are clear advantages in the cases which the permanent second molars were used for anchorage source, and this has been proposed convincingly by many authers. Therefore it is reasonable that orthodontists determine to include the permanent second molars among orthodontic treatment, but particular cases.

• The Journal of the Korean dental association
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• v.14 no.5
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• pp.457-459
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• 1976

The author experienced a failed ase of root resection which qas performed on the abnormal upper right lateral incisor. The patient was 16year old female. Clinically the effected tooth had neither a carious cavity nor periondontal diseases, ut, a fistula was present on the gum tissue near the root apex. The roentogenogram revealed a pathological area around the apex of the tooth. The results of failed apicoectomy lead to following conclusions. 1. The operated tooth was a case of dense invaginatus which had two pulp cavities and two canals seperated along their entire length. 2. It was the main cause of failure that the second pulp cavity and root canal were not obturated.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.38-47
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• 2003

Relationships between accumulations of endocrine disruptors and abnormalities in the reproductive organs in the adult male striped field mice, Apodemus agrarius, were reviewed. High levels of phenolic compounds were detected in the mice collected at an agricultural village in Gaduck island and at a place having a sewage problem in Samdong-myeon, Namhae. High levels of organo tin compounds were found in the mice collected at Jiri Mt. a tourist resort. Considerably high levels of phenolic or organo tin compounds were detected in mice with shrunken reproductive organs accounting for 14∼42% of the mice examined in each area, which suggests that the abnormality of reproductive organs may be induced by the endocrine disruptors. This hypothesis is strongly supported by histological observations of shrunken reproductive organs, such as necrosis of testicular germ and epithelial cells. This was found not only in the mice with shrunken reproductive organs but also in the mice with enlarged reproductive organs, both had accumulated high levels of endocrine disruptors in general.

• Journal of Chest Surgery
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• v.54 no.5
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• pp.393-395
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• 2021

The anomalous connection of umbilical vessels to the heart is rare and has not yet been reported in the international scientific literature. Herein, we report the case of a newborn who was diagnosed with an anomalous connection of the umbilical vessels to the left ventricle. These anomalous vessels were functionally open for 2 weeks, and cellulitis was present in the area of the blood vessels connected to the skin. We performed division of these abnormal vessels and removal of the skin lesion.

• Journal of the Korean Medical Association
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• v.61 no.11
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• pp.644-648
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• 2018

The incidence of skin cancer has continuously increased in Korea, probably due to sun exposure and increases in the aging population. Ultraviolet light, a well-known risk factor for skin cancer, can cause DNA damage, mutation, and immune suppression, followed by abnormal proliferation. To prevent photocarcinogenesis, the appropriate use of sunscreen should be emphasized. Using broad-spectrum sunscreens with sun protection factor values of 15 or higher and frequent reapplication are recommended. Controversy exists about whether vitamin D synthesis is inhibited by the use of sunscreen. However, considering that skin cancer most commonly develops on the head and neck area, applying it to the face and neck is reasonable in terms of balancing the risk-benefit ratio.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.640-651
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• 2022

Clinical studies on neuromodulation intervention for trigeminal neuralgia have not yet shown promising results. This might be due to the fact that the pathophysiology of chronic trigeminal neuropathy is not yet fully understood. Chronic trigeminal neuropathy includes trigeminal autonomic neuropathy, painful trigeminal neuropathy, and persistent idiopathic facial pain. This disorder is caused by complex abnormalities in the pain processing system, which is comprised of the affective, emotional, and sensory components, rather than mere abnormal sensation. Therefore, integrative understanding of the pain system is necessary for appropriate neuromodulation of chronic trigeminal neuropathy. The possible neuromodulation targets that participate in complex pain processing are as follows : the ventral posterior medial nucleus, periaqueductal gray, motor cortex, nucleus accumbens, subthalamic nucleus, globus pallidus internus, anterior cingulate cortex, hypothalamus, sphenopalatine ganglion, and occipital nerve. In conclusion, neuromodulation interventions for trigeminal neuralgia is yet to be elucidated; future advancements in this area are required.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.650-651
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• 2006

This paper presents a study of large grains by transmission electron microscopy in two WC-Co alloys, one W rich and one C rich. In the W rich alloy, some large grains are found in contact with the $\eta$ phase. The C content influences the morphology of large grains: they are flatter in the C rich alloy with smoother interfaces. Whatever the C content, they contain few dislocations compared to matrix grains except often in a small area. Small WC grains are often found inside the large grains. They have likely been engulfed during the growth of the large grains owing to the low boundary energy.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.691-694
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• 2021

The malalignment of the trunk causes abnormal stress in a specific area and lead to trunk instability. The purpose of this study was to investigate the correlation between the angle between the infrasternal angle and the trunk side shift distance. The participants in this study 22 subjects were participated. The infrasternal angle and trunk side shift distance were measured using a camera and analyzed using the Image J program. The correlation between the asymmetry of the infrasternal angle and trunk side shift distance was moderate (r=-0.413; p=0.028). According to the asymmetry of the infrasternal angle, it was confirmed that trunk lateral shift appeared in a specific direction. Based on result, it suggests that infrasternal angle and trunk side shift should be considered in the intervention plan of patients with asymmetry of the infrasternal angle.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.27-31
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• 2010

The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.