• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.206-209
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• 2003

The purpose of AR and HR coating is acquire the very low reflection rate and the high reflection rate through the deposition of a thin film using the refraction ofmaterial. Basically if the high refractive material and the low refractive material are chosen and the condition for the experiment is determined, then we solve theproject with the optical design and multi thin film coating. First of all, we choose $SiO_2$for the low refractive material and $TiO_2$ for the high refractive material and apply Sputtering System easy to control the refraction rate and excellent in reconstruction to the equipment of thin film multiplication. For the control of the refraction rate and growth rate we modify RF Power and the ratio of Gas(Ar:O2), And we use Ellipsometer for estimation and analysis of the refraction rate and growth rate and AFM&SEM for the analysis of surface and component.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.54-55
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• 2010

Vacancy defects in graphene can be created by electron or ion irradiation and those induce ripples which can change the electronic properties of graphene. Recently, the formation of defect structures such as vacancy defects and non-hexagonal rings has been reported in the high resolution transmission electron microscope (HR-TEM) of reduced graphene oxide [1]. In those HR-TEM images, it is noticed that the dislocations with pentagon-heptagon (5-7) pairs are formed and diffuses. Interestingly, it is also observed that two 5-7 pairs are separated and diffuse far away from each other. The separation of 5-7 pairs has been known to be due to their self-diffusion. However, from our tight-binding molecular dynamics simulation, it is found that the separation of 5-7 pairs is due to the diffusion of single vacancy defects and coalescence with 5-7 pairs. The diffusion and coalescence of single vacancy defects is too fast to be observed even in HR-TEM. We also implemented Van der Waals interaction in our tight-binding carbon model to describe correctly bi-layer and multi-layer graphene. The compressibility of graphite along c-axis in our tight-binding calculation is found to be in excellent agreement with experiment. We also discuss the difference between single layer and bi-layer graphene about vacancy diffusion and reconstruction.

• Archives of Plastic Surgery
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• v.38 no.3
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• pp.333-337
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• 2011

Purpose: Various operations have been proposed to compensate for congenital absence of the vagina using ileal or colonic interposition. These methods involve laparotomy, which shows postoperative complications such as long scar and delayed recovery. One case of neovagina reconstruction with laparoscopic rectosigmoid colpopoiesis in Mayer-Rokitansky-Kuster-Hauser syndrome is presented to avoid laparotomic complications. Methods: Laparoscopic surgery was performed in a 27-year-old MRKH syndrome patient. After a cruciate incision, blunt dissection through two-finger wide space was created between the bladder and the rectum. A 14-cm rectosigmoid segment vascularized by a branch of sigmoid artery was isolated by laparoscopy. The distal end was sutured with vaginal vestibule mucosa. A continuity of intestine was restored by circular end-to-end proximate curved intraluminal stapler CDH29$^{(R)}$ through perineal opening. Results: Total operation time was 4 hr 15 min. Normal walking and ingestion were possible within 3 days and 4 days after surgery. The hospital stay was 7 days and the patient was followed up for 6 months. The neovaginal introitus was wide enough for inserting two fingers, and there has been no narrowing of the neovagina on palpation as confirmed by vaginogram. The patient had functional self-lubricating neovagina without excessive mucous production or the need for routine dilation or unnoticeable scar. Conclusion: The successful result of this laparoscopic vaginal reconstruction technique with rectosigmoid segment suggests that this technique can be considered for the option of vaginal reconstruction in girls with the MRKH syndrome.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.4
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• pp.543-548
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• 2021

The higher the resolution of the image, the higher the satisfaction of the viewers of the image, and the super-resolution imaging has a considerable increase in research value among the fields of computer vision and image processing. In this study, the main features of low-resolution image LR are extracted mainly using deep learning super-resolution models. It learns and reconstructs the extracted features, and focuses on reconstruction-based algorithms that generate high-resolution image HR. In this paper, we investigate SRCNN and VDSR in a super-resolution algorithm model based on reconstruction. The structure and algorithm process of the SRCNN and VDSR model are briefly introduced, and the multi-channel and special form are also examined in the improved performance evaluation function, and understand the performance of each algorithm through experiments. In the experiment, an experiment was performed to compare the results of the SRCNN and VDSR models with the peak signal-to-noise ratio and image structure similarity, so that the results can be easily judged.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.5
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• pp.284-293
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• 2013

Purpose: For reconstruction of craniomaxillofacial defects caused by tumor, trauma, infection etc, free flap transplantation with microvascular surgery is a very useful method. Thrombus formation at the anastomosis site is the major cause of graft failure. 4-Hexylresorcinol (4-HR) is generally known as an antiseptic and antiparasitic agent. This study was conducted in order to evaluate the effect of 4-HR on blood coagulation in vitro. In addition, we investigated thrombus formation and endothelial repair of an injured vessel in an animal model. Methods: In the in vitro experiment, we compared blood coagulation time between the 4-HR treated group and normal blood. Thirty rats were used for in vivo animal experiments. After exposure of the right femoral vein, a micro vessel clamp was placed and the femoral vein was intentionally cut. Microvascular anastomosis was performed on all rats using 10-0 nylon under microscopy. The animals were divided into two groups. In the experimental group (n=15), 4-HR (250 mg/kg) mixed with olive oil (10 mL/kg) was administered per os daily. Animals in the control group (n=15) were given olive oil only. The animals were sacrificed at three days, seven days, and fourteen days after surgery and rat femoral vein samples were taken. Vascular patency and thrombus formation were investigated just before sacrifice. Histologic analysis was performed under a microscope. Results: Results of an in vitro blood coagulation test showed that coagulation time was delayed in the 4-HR treated group. The results obtained from an in vivo 4-HR administered rat model showed that the patency of all experimental groups was better at thirty minutes, seven days, and fourteen days after microvascular anastomosis than that of the control group at seven and fourteen days after anastomosis, and the amount of thrombus in the experimental groups was much less than that of the control group. Endothelial repair was observed in the histologic analysis. Conclusion: Findings of this study demonstrated that blood coagulation was delayed in the vitro 4-HR treated group. In addition, good vascular patency, anti-thrombotic effect, and repair of venous endothelial cells were observed in the vivo 4-HR administered rat group.

• Current Optics and Photonics
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• v.2 no.2
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• pp.165-171
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• 2018

Fourier ptychographic microscopy (FPM) is a recently proposed computational imaging method that achieves both high resolution (HR) and wide field of view. In the FPM framework, a series of low-resolution (LR) images at different illumination angles is used for high-resolution image reconstruction. On the basis of previous research, image noise can significantly degrade the FPM reconstruction result. Since the captured LR images contain a lot of dark-field images with low signal-to-noise ratio, it is very important to apply a noise-reduction process to the FPM raw dataset. However, the thresholding method commonly used for the FPM data preprocessing cannot separate signals from background noise effectively. In this work, we propose an improved thresholding method that provides a reliable background-noise threshold for noise reduction. Experimental results show that the proposed method is more efficient and robust than the conventional thresholding method.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.1
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• pp.120-127
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• 2010

This paper presents a SR method using adaptive interpolation based on local gradient features to obtain a high quality SR image. In this method, the distance between the interpolated pixel and the neighboring valid pixel is considered by using local gradient properties. The interpolation coefficients take the local gradient of the LR images into account. The smaller the local gradient of a pixel is, the more influence it should have on the interpolated pixel. And the median filter is finally applied to reduce the blurring and noise of the interpolated HR image. Experiment results show the effectiveness of the proposed method in comparison with other methods, especially in the edge areas of the images.

• Architectural research
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• v.15 no.3
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• pp.133-141
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• 2013

The purpose of this paper is to highlight the main policies of the last half century that have shaped the urban architectural fabric of Seoul today, and explore whether a modified approach might better address the current socioeconomic conditions in Korea. The paper defines and examines urban planning in Korea through an overview of the four main urban project policies implemented in Seoul from the 1960s to the present: Land Readjustment (LR), Housing Site Development (HSD), Urban Redevelopment (UR), and Housing Reconstruction (HR). While the fundamental ideology behind these policies served well during a prolonged period of high economic growth, evidence is growing that these policies are losing steam under today's conditions. A growing legacy of stalled and incomplete urban projects from the mid-2000s-the New Town Project is an example-begs the fundamental question as to whether an alternative urban planning paradigm is needed for Korea in an age of low economic growth, low birth rates and a fossil fuel energy crisis. Through the urban morphologies of the three residential areas in Seoul developed by LR projects, this paper looks at the possibility of urban regeneration through the sustainment of urban architecture in those residential areas that have not been affected by HSD, UR, and HR.

• Journal of Chest Surgery
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• v.52 no.5
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• pp.360-367
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• 2019

Background: Primary chest wall sarcoma is a rare disease with limited reports of surgical resection. Methods: This retrospective review included 41 patients with primary chest wall sarcoma who underwent chest wall resection and reconstruction from 2001 to 2015. The clinical, histologic, and surgical variables were collected and analyzed by univariate and multivariate Cox regression analyses for overall survival (OS) and recurrence-free survival (RFS). Results: The OS rates at 5 and 10 years were 73% and 61%, respectively. The RFS rate at 10 years was 57.1%. Multivariate Cox regression analysis revealed old age (hazard ratio [HR], 5.16; 95% confidence interval [CI], 1.71-15.48) as a significant risk factor for death. A surgical resection margin distance of less than 1.5 cm (HR, 15.759; 95% CI, 1.78-139.46) and histologic grade III (HR, 28.36; 95% CI, 2.76-290.87) were independent risk factors for recurrence. Conclusion: Long-term OS and RFS after the surgical resection of primary chest wall sarcoma were clinically acceptable.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.6
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• pp.370-374
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• 2016

Mucoepidermoid carcinoma (MEC) is the most common type of malignant neoplasm in the minor salivary gland. The hard palate is a frequently involved site of MEC. The treatment of low-grade MEC on the hard palate is wide local resection with a tumor-free margin. In the present case, the maxillary defect was reconstructed using a buccal fat pad (BFP) flap, followed by application of 4-hexylresorcinol (4HR) ointment for 2 weeks. The grafted BFP successfully covered the tumor resection defect without tension and demonstrated complete re-epithelialization without any complications.