• Journal of The Korean Ophthalmological Society
• /
• v.59 no.11
• /
• pp.1091-1096
• /
• 2018

Purpose: We report a case of bilateral nonarteritic anterior ischemic optic neuropathy (NAION) following acute angle-closure crisis (AACC). Case summary: A 76-year-old female visited our clinic because of a 1-day history of ocular pain and vision loss in both eyes. The visual acuity was 0.02 in both eyes and her intraocular pressure (IOP) was 52 mmHg in the right eye (RE) and 50 mmHg in the left eye (LE). She had corneal edema and a shallow anterior chamber in both eyes, with 4 mm fixed dilated pupils. After decreasing the IOP with intravenous mannitol, laser iridotomy was performed. However, 2 days later, visual acuity was further reduced to finger counting at 10 cm RE and at 50 cm LE, and her optic disc was swollen. Bilateral NAION following AACC was diagnosed. One month later, visual acuity slightly improved to 0.02 RE and 0.04 LE, and the optic disc edema resolved. A small cup-disc ratio, optic disc pallor, and atrophy were observed. Humphrey visual fields demonstrated superior and inferior altitudial visual field defects in the LE, and almost total scotoma in the RE. Conclusions: AACC can be a predisposing factor for NAION, so the relative afferent pupillary defect, papilledema, and presentation of other risk factors are important clues to a diagnosis of NAION.

• KIPS Transactions on Computer and Communication Systems
• /
• v.10 no.7
• /
• pp.199-204
• /
• 2021

Digital substation refers to a substation that digitizes functions and communication methods of power facilities such as monitoring, measuring, control, protection, and operation based on IEC 61850, an international standard for the purpose of intelligent power grids. Based on the intelligent operating system, efficient monitoring and control of power facilities is possible, and automatic recovery function and remote control are possible in the event of an accident, enabling rapid power failure recovery. With the development of digital technology and the expansion of the introduction of eco-friendly renewable energy and electric vehicles, the spread of direct current distribution systems is expected to expand. MVDC is a system that utilizes direct current lines with voltage levels and transmission capacities between HVDCs applied to conventional transmission systems and LVDCs from consumers. Converting existing lines in substations, where most power equipment is alternating current centric, to direct current lines will reduce transmission losses and ensure greater current capacity. The process bus of a digital substation is a communication network consisting of communication equipment such as Ethernet switches that connect installed devices between bay level and process level. For MVDC linkage to existing digital substations, the process level was divided into two buses: AC and DC, and a system that can be comprehensively managed in conjunction with diagnostic IEDs as well as surveillance and control was proposed.

• Journal of the Korean Geosynthetics Society
• /
• v.19 no.4
• /
• pp.41-50
• /
• 2020

Since cracks in concrete structures expedite corrosion of reinforced concrete over a long period of time, regular on-site inspections are essential to ensure structural usability and prevent degradation. Most of the safety inspections of facilities rely on visual inspection with naked eye, so cost and time consuming are severe, and the reliability of results differs depending on the inspector. In this study, a portable measuring device that can be used for safety diagnosis and maintenance was developed as a device that measures the width and length of concrete cracks through image analysis of cracks photographed with a camera. This device captures the cracks found within a close distance (3 m), and accurately calculates the unit pixel size by laser distance measurement, and automatically calculates the crack length and width with the image processing algorithm developed in this study. In measurement results using the crack image applied to the experiment, the measurement of the length of a 0.3 mm crack within a distance of 3 m was possible with a range of about 10% error. The crack width showed a tendency to be overestimated by detecting surrounding pixels due to vibration and blurring effect during the binarization process, but it could be effectively corrected by applying the crack width reduction function.

• The Journal of the Korea Contents Association
• /
• v.22 no.3
• /
• pp.71-80
• /
• 2022

In the past, fish diseases were bacterial in aqua farms, but in recent years, the frequency of fish diseases has increased as they have become viral and mixed. Viral diseases in an enclosed space called a aqua farm have a high spread rate, so it is very likely to lead to mass death. Fast identification of fish diseases is important to prevent group death. However, diagnosis of fish diseases requires a high level of expertise and it is difficult to visually check the condition of fish every time. In order to prevent the spread of the disease, an automatic identification system of diseases or fish is needed. In this paper, in order to improve the performance of the disease identification system of Paralichthys olivaceus based on deep learning, the existing pre-processing method is compared and tested. Target diseases were selected from three most frequent diseases such as Scutica, Vibrio, and Lymphocystis in Paralichthys olivaceus. The RGB, HLS, HSV, LAB, LUV, XYZ, and YCRCV were used as image pre-processing methods. As a result of the experiment, HLS was able to get the best results than using general RGB. It is expected that the fish disease identification system can be advanced by improving the recognition rate of diseases in a simple way.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.2
• /
• pp.85-95
• /
• 2021

Currently, we stand between computers as creative tools and computers as creators. A new genre of movies, which can be called a post-cinema situation, is emerging. This paper aims to diagnose the possibility of the emergence of AI cinema. To confirm the possibility of AI cinema, it was examined through a case study whether the creation of a story, narrative, image, and sound, which are necessary conditions for film creation, is possible by artificial intelligence. First, we checked the visual creation of AI painting algorithms Obvious, GAN, and CAN. Second, AI music has already entered the distribution stage in the market in cooperation with humans. Third, AI can already complete drama scripts, and automatic scenario creation programs using big data are also gaining popularity. That said, we confirmed that the filmmaking requirements could be met with AI algorithms. From the perspective of Manovich's 'AI Genre Convention', web documentaries and desktop documentaries, typical trends post-cinema, can be said to be representative genres that can be expected as AI cinemas. The conditions for AI, web documentaries and desktop documentaries to exist are the same. This article suggests a new path for the media of the 4th Industrial Revolution era through research on AI as a creator of post-cinema.

• Korean Journal of Clinical Laboratory Science
• /
• v.56 no.2
• /
• pp.135-146
• /
• 2024

Urinalysis is a fundamental diagnostic test routinely performed in clinical laboratories. We evaluated two manual microscopy methods, including a novel protocol, against the standardized chamber method. A total of 402 specimens, comprising 201 positive each for red blood cells (RBCs) and white blood cells (WBCs) by the strip test and automated urine sediment analyzer, were selected for the analysis. The correlation coefficients between the standardized chamber method and the novel protocol RBC and WBC test were both r=0.98, indicating a high degree of correlation. The pair-wise agreement rates for the same grade between these two methods were 86.1% for RBCs and 88.6% for WBCs, with rates within one grade difference of both at 99.5%. In contrast, the agreement rates between the standardized chamber method and smaller or medium-sized laboratory methods were notably lower, with the same-grade rates at 11.9% for RBCs and 13.4% for WBCs, and within one grade difference at 67.2% and 74.1%, respectively. Additional analyses using the intraclass correlation coefficient and Bland-Altman plots confirmed that the novel protocol exhibited superior agreement compared to the other three manual microscopy methods tested. Therefore, we recommend the novel protocol as a standardized procedure for urine sediment preparation, given its high correlation and agreement with the standardized chamber method.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.23 no.2
• /
• pp.119-131
• /
• 2024

Understanding accurate traffic performance is crucial for ensuring efficient highway operation and providing a sustainable mobility environment. On the other hand, an immediate and precise estimation of highway traffic performance faces challenges because of infrastructure and technological constraints, data processing complexities, and limitations in using integrated big data. This paper introduces a framework for estimating traffic performance by analyzing real-time data sourced from toll collection systems and dedicated short-range communications used on highways. In particular, this study addresses the data errors arising from segmented information in data, influencing the individual travel trajectories of vehicles and establishing a more reliable Origin-Destination (OD) framework. The study revealed the necessity of trip linkage for accurate estimations when consecutive segments of individual vehicle travel within the OD occur within a 20-minute window. By linking these trip ODs, the daily average highway traffic performance for South Korea was estimated to be248,624 thousand vehicle kilometers per day. This value shows an increase of approximately 458 thousand vehicle kilometers per day compared to the 248,166 thousand vehicle kilometers per day reported in the highway operations manual. This outcome highlights the potential for supplementing previously omitted traffic performance data through the methodology proposed in this study.

• Journal of Gastric Cancer
• /
• v.5 no.4 s.20
• /
• pp.246-251
• /
• 2005

Purpose: Benign anastomotic stricture after an esophagojejunostomy using EEA stapler following a radical total gastrectomy is one of the most serious complications. The purpose of this study is to evaluate the incidence risk factors, and treatment associated with benign stricture. Materials and Methods: From March 1998 to February 2001, 436 patients underwent an esophagojejunostomy with Roux-en-Y anastomosis using an EEA stapler followed by an endoscopy. Thirty three of the 436 patients(5.5%) developed an anastomotic stricture; included 24 of the 33 patients had a benign stricture. Nine patients with a malignant stricture were excluded. Results: The median age of the 436 patients was 57 years $(23{\sim}85\;years)$. Two hundred ninety two patients were male, and 144 patients were female. The median time to diagnosing the stricture was 1.5 months $(0.5{\sim}6months)$. There was no statistical significance in any of the risk factors, including the diameter of the stapling device, the status of adjuvant treatment, the status of reflux esophagitis, and a clinical history of diabetes and hypertension. The strictured patients were treated with balloon dilatation, one to three times, with symptom relief. Conclusion: There were no statistically significant risk factors. However, further study of the vascularity of anastomoses and benign strictures needs to be considered. In the anastomotic strictured patients endoscopic balloon dilatation appeared to be the first line of treatment.

• Progress in Medical Physics
• /
• v.24 no.2
• /
• pp.99-107
• /
• 2013

The surgical resection was occurred mainly in liver metastasis before the development of radiation therapy techniques. Recently, Radiation therapy is increased gradually due to the development of radiation dose delivery techniques. 18F-FDG PET image showed better sensitivity and specificity in liver metastasis detection. This image modality is important in the radiation treatment with planning CT for tumor delineation. In this study, we applied automatic image segmentation methods on PET image of liver metastasis and examined the impact of image factors on these methods. We selected the patients who were received the radiation therapy and 18F-FDG PET/CT in Korea Cancer Center Hospital from 2009 to 2012. Then, three kinds of image segmentation methods had been applied; The relative threshold method, the Gradient method and the region growing method. Based on these results, we performed statistical analysis in two directions. 1. comparison of GTV and image segmentation results. 2. performance of regression analysis for relation between image factor affecting image segmentation techniques. The mean volume of GTV was $60.9{\pm}65.9$ cc and the $GTV_{40%}$ was $22.43{\pm}35.27$ cc, and the $GTV_{50%}$ was $10.11{\pm}17.92$ cc, the $GTV_{RG}$ was $32.89{\pm}36.8$4 cc, the $GTV_{GD}$ was $30.34{\pm}35.77$ cc, respectively. The most similar segmentation method with the GTV result was the region growing method. For the quantitative analysis of the image factors which influenced on the region growing method, we used the standardized coefficient ${\beta}$, factors affecting the region growing method show GTV, $TumorSUV_{MAX/MIN}$, $SUV_{max}$, TBR in order. The result of the region growing (automatic segmentation) method showed the most similar result with the CT based GTV and the region growing method was affected by image factors. If we define the tumor volume by the auto image segmentation method which reflect the PET image parameters, more accurate and consistent tumor contouring can be done. And we can irradiate the optimized radiation dose to the cancer, ultimately.

• Journal of Gastric Cancer
• /
• v.5 no.1
• /
• pp.16-22
• /
• 2005

Purpose: In Korea, the number of laparoscopy-assisted distal gastrectomies for early gastric cancer patients has been increasing lately. Although minimally invasive surgery is more beneficial, no reported case of a totally laparoscopic distal gastrectomy has been reported because of difficulty with intracorporeal anastomosis. This study attempts, through our experiences, to determine the feasibility of a totally laparoscopic distal gastrectomy using an intracorporeal gastroduodenostomy in treating early gastric carcinoma. Materials and Methods: We investigated surgical results and clinicopatholgic characteristics of eight(8) patients with an early gastric carcinoma who underwent a totally laparoscopic distal gastrectomy at the Department of Surgery, Our Lady of Mercy Hospital, The Catholic University of Korea, between June 2004 and September 2004. The intracorporeal gastroduodenostomy was performed with a delta-shaped ananstomosis by using only laparoscopic linear staplers (Endocutter 45mm; Ethicon Endosurgery, OH, USA). Results: The operative time was $369.4\pm62.5$ minutes (range $275\∼465$ minutes), and the anastomotic time was 45.1\pm14.4$ minutes (range $32\∼70$ minutes). The anastomotic time was shortened as surgical experience was gained. The number of laparoscopic linear staplers for an operation was $7.1\pm0.6$. The number of lymph nodes harvested was $31.9\pm13.1$. There was 1 case of transfusion and no case of conversion to an open procedure. The time to the first flatus was 2.8$\pm$0.5 days, and the time to the first food intake was $4.1\pm0.8$ days. There were no early postoperative complications, and the postoperative hospital stay was $10.0\pm3.9$ days. Conclusion: A totally laparoscopic distal gastrectomy using an intracorporeal gastroduodenostomy with a delta-shaped anastomosis is technically feasible and can maximize the benefit of laparoscopic surgery for early gastric cancer.