• Journal of radiological science and technology
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• v.28 no.4
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• pp.327-332
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• 2005

The purpose of this Study was to investigate the prevalence rate of idiopathic scoliosis to the students from the elementary to the university in S city of Chung-Nam using 100 mm Mirror Camera radiation indirect examination units, with on age range of between eight and thirteen (1.526 subjects), fourteen and sixteen (462 subjects), seventeen and eighteen (291 subjects), nineteen and twenty four(508 subjects) and total of 2,787 participants with the 590 male subjects and 2,197 female subjects. The results of this study can be summarized and compared the primary examination with the secondary test of greater than $10^{\circ}$of Cobb's Angle were obtained as follows; 1. Indirect Examination were conducted to find idiopathic scoliosis amomg total 2.787 subjects, 257 subjects (9.2%) who showed positive sign greater than $10^{\circ}$in the Cobb's Angle ; below age of thirteen (132 subjects), between fourteen and sixteen (52 subjects), seventeen and eighteen (35 subjects), nineteen and twenty four (38 subjects). The $x^2-test$ analysis of Indirect Examination showed no statistical significant difference association between the age range and $10^{\circ}$Cobb's Angle of spinal curve(P>0.059). 2. The numbers of idiopathic scoliosis of greater than $10^{\circ}$Cobb's Angle of spinal curve in the primary examination were observed in 147 subjects (57.2%) at the Thoracolumbar region, 81subjects (31.5%) at the Thoracic region, 20 subjects (7.8%) at the Cervicothoracic region, 7 subjects (2.7%) at the Lumbar region, 2 subjects (0.8%) at the Cervical region. So, the large numbers were Thoracolumbar region, 183 participants (71.2%) showed the right side curve of scoliosis and 74 participant (28.8%) showed the left side curve of scoliosis. 3. The main region of the pain in one's own self more than $10^{\circ}$ Cobb's angle of spinal curve were no pain 219 subjects (85.2%), 18 subjects (7.0%) at the Lumbar region, 9 subjects (3.5%) at the Cervical region, 7 subjects (2.7%) at the Thoracic region, 2 subjects (0.7%) at the shoulder girdle region, 1 subjects (0.39%) at the pelvis and whole body region. There was statistical significant difference association between the Cobb's Angle of spinal curve and the main pain region of one's (P<0.006). This study may be significant to an early stage investigate of the prevalence rate of idiopathic scoliosis in the juveniles using 100 mm Mirror Camera radiation indirect examination units. The results of this study help that the students in a stage on growth the basis of data early discovery and therapy of idiopathic scoliosis.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.483-488
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• 2022

In this paper, when a gain grating and a refractive index grating exist simultaneously in a DFB laser diode having a wavelength of 1.55 ㎛, an anti-reflection coating is applied to the right mirror surface so that ρ_r=0. In case of δL<0, the characteristics of the oscillation frequency and oscillation gain have been analyzed. Whenever the phase of the grating on the left side of the mirror continuously decreases by π/2, the δL value of each oscillation mode decreases by about 0.6 to the left of the graph lines of each oscillation mode. The case of the oscillation mode having the lowest threshold gain is the case of κL=10, and in this case, the mode selectivity is relatively low compared to the case of other values of κL. From κL=0.1 to κL=6, the mode selectivity and the frequency stability are excellent. As the mode selectivity is excellent, the frequency stability is excellent. Compared to the case with two cleaved mirrors, the DFB laser diode with anti-reflection coating increases the threshold gain of the oscillation mode by about 2 times, but the mode selectivity becomes about 2 times better.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.718-724
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• 2012

This study aims to examine effects of vision control balance training applied to stroke patients on their balance. 26 stroke patients, the subjects of this study, were divided into an affected side 1/2 vision control group (9), a non-affected side 1/2 vision control group (9), and a non-vision control group (8). After vision control standing on Posturo-med, all of the three groups received balance training 20 minutes four times per week for 8 weeks watching themselves 1M away from a mirror. To measure their balance abilities, measurements were made on their time of balance maintenance and muscle activity prior to the intervention, four 4 after the intervention, and 8 weeks after the intervention. Vision control balance training applied to stroke patients resulted in increase in their time of balance maintenance and significant improvement in vastus medialis muscle activity (p<0.05). This study result is that vision control balance training is considered an effective exercise method for balance training of stroke patients.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.3
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• pp.89-93
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• 2020

Complex warpage behavior of the electronic packages causes internal stress so many kinds of mechanical failure occur such as delamination or crack. Efforts to predict the warpage behavior accurately in order to prevent the decrease in yield have been approached from various aspects. For warpage prediction, silicon is generally treated as a homogeneous material, therefore it is described as showing no warpage behavior due to thermal loading. However, it was reported that warpage is actually caused by residual stress accumulated during grinding and polishing in order to make silicon wafer thinner, which make silicon wafer inhomogeneous through thickness direction. In this paper, warpage behavior of the single-side polished wafer at solder reflow temperature, the highest temperature in packaging processes, was measured using 3D digital image correlation (DIC) method. Mechanism was verified by measuring coefficient of thermal expansion (CTE) of both mirror-polished surface and rough surface.

• Journal of International Society for Simulation Surgery
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• v.2 no.2
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• pp.90-93
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• 2015

The fibula free flap has now become the most reliable and frequently used option for mandible reconstruction. Recently, three dimensional images and printing technologies are applied to mandibular reconstruction. We introduce our recent experience of mandibular reconstruction using three dimensionally planned fibula free flap in a patient with gunshot injury. The defect was virtually reconstructed with three-dimensional image. Because bone fragments are dislocated from original position, relocation was necessary. Fragments are virtually relocated to original position using mirror image of unaffected right side of the mandible. A medical rapid prototyping (MRP) model and cutting guide was made with 3D printer. Titanium reconstruction plate was adapted to the MRP model manually. 7 cm-sized fibula bone flap was designed on left lower leg. After dissection, proximal and distal margin of fibula flap was osteotomized by using three dimensional cutting guide. Segmentation was also done as planned. The fibula bone flap was attached to the inner side of the prebent reconstruction plate and fixed with screws. Postoperative evaluation was done by comparison between preoperative planning and surgical outcome. Although dislocated condyle is still not in ideal position, we can see that reconstruction was done as planned.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2518-2520
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• 1998

Silicon can be reactive ion etched (RIE) either isotropically or anisotropically. In this paper, a new micromachining technology combining these two etching characteristics is proposed. In the proposed method, the fabrication steps are as follows. First. a polysilicon layer, which is used as the bottom electrode, is deposited on the silicon wafer and patterned. Then the silicon substrate is etched anisotropically to a few micrometer depth that forms a cavity. Then an PECVD oxide layer is deposited to passivate the cavity side walls. The oxide layers at the top and bottom faces are removed while the passivation layers of the side walls are left. Then the substrate is etched again but in an isotropic etch condition to form a round trench with a larger radius than the anisotropic cavity. Then a sacrificial PECVD oxide layer is deposited and patterned. Then a polysilicon structural layer is deposited and patterned. This polysilicon layer forms a pivot structure of a rocker-arm. Finally, oxide sacrificial layers are etched away. This new micromachining technology is quite simpler than conventional method to fabricate joint structures, and the devices that are fabricated using this technology do not require a flexing structure for motion.

• Journal of International Society for Simulation Surgery
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• v.3 no.1
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• pp.36-38
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• 2016

Fibrous dysplasia is a relatively rare disease but the management would be quite challenging. Because this is not a malignant tumor, the preservation of the facial contour and the various functions seems to be important in treatment planning. Until now the facial bone reconstruction with autogenous bone would be the standard. Although the autogenous bone would be the ideal one for facial bone reconstruction, donor site morbidity would be the inevitable problem in many cases. Meanwhile, various types of allogenic and alloplastic materials have been also used. However, facial bone reconstruction with many alloplastic material have produced no less complications including infection, exposure, and delayed wound healing. Because the 3D printing technique evolved so fast that 3D printed titanium implant were possible recently. The aim of this trial is to try to restore the original maxillary anatomy as possible using the 3D printing model, based on the mirrored three dimensional CT images based on the computer simulation. Preoperative computed tomography (CT) data were processed for the patient and a rapid prototyping (RP) model was produced. At the same time, the uninjured side was mirrored and superimposed onto the traumatized side, to create a mirror-image of the RP model. And we molded Titanium mesh to reconstruct three-dimensional maxillary structure during the operation. This prefabricated Titanium-mesh implant was then inserted onto the defected maxilla and fixed. Three dimensional printing technique of titanium material based on the computer simulation turned out to be successful in this patient. Individualized approach for each patient could be an ideal way to restore the facial bone.

• Journal of International Society for Simulation Surgery
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• v.1 no.2
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• pp.99-102
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• 2014

The skull defect can be made after the trauma, oncologic problems or neurosurgery. The skull reconstruction has been the challenging issue in craniofacial fields for a long time. So far the skull reconstruction with autogenous bone would be the standard. Although the autogenous bone would be the ideal one for skull reconstruction, donor site morbidity would be the inevitable problem in many cases. Meanwhile various types of allogenic and alloplastic materials have been also used. However, skull reconstruction with many alloplastic material have produced no less complications including infection, exposure, and delayed wound healing. Because the 3D printing technique evolved so fast that 3D printed titanium implant were possible recently. The aim of this trial is to try to restore the original skull anatomy as possible using the 3D printed titanium implant, based on the mirrored three dimensional CT images based on the computer simulation. Preoperative computed tomography (CT) data were processed for the patient and a rapid prototyping (RP) model was produced. At the same time, the uninjured side was mirrored and superimposed onto the traumatized side, to create a mirror-image of the RP model. And we fabricated Titanium implant to reconstruct three-dimensional orbital structure in advance, using the 3D printer. This prefabricated Titanium-implant was then inserted onto the defected skull and fixed. Three dimensional printing technique of titanium material based on the computer simulation turned out to be very successful in this patient. Individualized approach for each patient could be an ideal way to manage the traumatic patients in near future.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.3
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• pp.322-327
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• 2023

Situs inversus totalis (SIT) is a rare condition in which cardiac and abdominal organs are inverted from their normal left-sided orientation. Mirizzi syndrome, characterized by the obstruction of the common hepatic duct or the common bile duct by gallstone, is a rare condition. Mirizzi syndrome co-occurrence in SIT patients is rare. Gallbladder in sinistroposition is extremely uncommon in SIT patients. We report a known case of diabetes, ventricular septal defect with transposition of the great arteries in a 32-year-old female who presented with jaundice, cholangitis, chills, and fever that had lasted for 10 days. She was confirmed to have SIT with type III Mirizzi syndrome following a series of diagnostic procedures. Primarily, endoscopic retrograde cholangiopancreatography along with common bile duct stenting was performed to initially reduce cholangitis. After an eight-week follow-up after the reduction of cholangitis, surgery was conducted. Mirror-imaged ports were used for the laparoscopic procedure, and the surgeon was on the patient's right side rather than the usual left side. The patient was discharged from the hospital following two days of uneventful healing.

• Korean Journal of Optics and Photonics
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• v.32 no.6
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• pp.286-295
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• 2021

A modified catadioptric omnidirectional optical system (MCOOS) using an RGB/NIR CMOS sensor is optically designed for a capsule endoscope with the front field of view (FOV) in visible light (RGB) and side FOV in visible and near-infrared (NIR) light. The front image is captured by the front imaging lens system of the MCOOS, which consists of an additional three lenses arranged behind the secondary mirror of the catadioptric omnidirectional optical system (COOS) and the imaging lens system of the COOS. The side image is properly formed by the COOS. The Nyquist frequencies of the sensor in the RGB and NIR spectra are 90 lp/mm and 180 lp/mm, respectively. The overall length of 12 mm, F-number of 3.5, and two half-angles of front and side half FOV of 70° and 50°-120° of the MCOOS are determined by the design specifications. As a result, a spatial frequency of 154 lp/mm at a modulation transfer function (MTF) of 0.3, a depth of focus (DOF) of -0.051-+0.052 mm, and a cumulative probability of tolerance (CPT) of 99% are obtained from the COOS. Also, the spatial frequency at MTF of 170 lp/mm, DOF of -0.035-0.051 mm, and CPT of 99.9% are attained from the front-imaging lens system of the optimized MCOOS.