• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2015.07a
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• pp.75-77
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• 2015

디스플레이 해상도가 지속적으로 고해상화가 되면서, 기존 저해상도 영상을 고해상도 디스플레이 크기에 맞춰 해상도를 키우는 기법인 초해상화(super-resolution, SR) 기법에 많은 관심이 쏟아지고 있으며 이에 대한 많은 초해상화 논문들이 게재되었다. 이 중 현재 최상 품질의 고해상도 영상을 복원하는 한 초해상화 기법은, 입력 받은 저해상도 영상을 자가 예제(self-examples)로 사용하여 선형 매핑(linear mapping)을 통해 점진적으로 여러 레벨(level)를 거쳐 조금씩 키우는 방법이다. 이때 각 레벨마다 기존 저해상도 영상 크기로 반복적으로 줄여 오차를 줄이는 역투영법(back-projection)을 사용하는데, 이 방법은 처리된 영상에 시각적 품질을 낮추는 링 아티팩트(ringing artifacts)를 생산하며, 이는 매 레벨마다 계속 누적이 되어 고해상도 결과 이미지 품질에 악영향을 미치는 단점이 있다. 이를 보완하기 위해, 본 논문에서는 저해상도 정지 영상을 고해상도 정지 영상으로 점진적으로 키울 때 일반적인 역투영법 대신 비국소적 평균법(non-local means, NLM) 기반 역투영법을 사용하는 초해상화 기법을 제안한다. 제안하는 기법은 매 레벨마다 생기는 링 아티팩트를 효과적으로 제거하여 높은 시각적 품질의 고해상도 영상을 복원할 수 있게 한다. 실험을 통해 제안된 초해상화 기법을 사용 시 기존 초해상화 기법보다 향상된 고품질 고해상도 영상 복원이 가능한 것을 확인하였다.

• Journal of the Institute of Convergence Signal Processing
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• v.23 no.1
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• pp.8-14
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• 2022

With the development of deep learning, super-resolution (SR) methods have tried to use deep learning mechanism, instead of using simple interpolation. SR methods using deep learning is generally based on convolutional neural networks (CNN), but recently, SR researches using attention mechanism have been actively conducted. In this paper, we propose an approach of improving SR performance using one of the attention mechanisms, non-local sparse attention (NLSA). Through experiments, we confirmed that the performance of the existing SR models, IMDN, CARN, and OISR-LF-s can be improved by using NLSA.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.59-67
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• 2020

In this study, a suitable algorithm for each BRT stop type is presented through the network construction and algorithm design effect analysis through the LISA, a traffic signal program, for the BRT stop type in the BRT Design Guidelines, Ministry of Land, Transport and Maritime Affairs, 2010.6. It was. The phase insert technique is the most effective method for the stop before passing the intersection, the early green technique for the stop after the intersection, and the extend green technique for the mid-block type stop. The extension green technique is used only because it consists of BRT vehicles, general vehicles and pedestrians. Analyzed. After passing through the intersection, the stop was analyzed as 56.4 seconds for the total crossing time and 29.8 seconds for the delay time. In the mid-block type stop, the total travel time of the intersection was 40.5 seconds, the delay time was 9.6 seconds, the average travel time of up and down BRT was 70.2 seconds, the delay time was 14.0 seconds, and the number of passages was 29.

• Journal of the Korea Convergence Society
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• v.5 no.4
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• pp.137-146
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• 2014

This study investigated the effects of response prompting through 3-steps compliance training to reaction time for child with Asperger's syndrome(AS). The participant was 3 and 8 year-old boy who was diagnostic As with non-compliant, delayed receptive language. Study design was multiple-baseline across behaviors. Target Behaviors were hands-up, following direction, and answering behavior. Dependent variable was latency reaction time during compliance training. This results mean that reaction time was increased raise hands-up behavior, compliance behavior and response ask questions. During intervention, the participant improve the rate on-task behavior as well as reduce off-task behaviors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1391-1397
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• 2016

We investigated the hepatoprotective effects of Angelica keiskei Koidzumi extract (AK) in HepG2-overexpressing cytochrome P4502E1 (CYP2E1) and C57BL/6J mice. In HepG2 cells expressing CYP2E1, cell viability and catalase activity in the ethanol-AK co-treated group significantly increased compared to those in the ethanol-treated group. In the in vivo study with C57BL/6J mice, the AK-supplemented group with ethanol liquid diet showed significantly reduced hepatic markers, including serum aspartate aminotransferase, alanine aminotransferase, and ${\gamma}$-glutamyl transferase, compared to the ethanol group without AK supplementation. AK supplementation (20 mg/kg BW/d) also significantly attenuated reactive oxygen species generation and malondialdehyde level. Notably, a low dose of AK supplementation (20 mg/kg BW/d) suppressed expression of hepatic CYP2E1 and inhibited CYP2E1 enzyme activity. These data indicate that a low dose of AK supplementation could restrain alcohol-induced hepatic damage mediated by CYP2E1.

• Korean Security Journal
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• no.36
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• pp.293-316
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• 2013

Today's high-rise buildings are increasing concern about the safety and evacuation of people related to the fire and threat from outside. Terrorism breaking out in high-rise buildings, a symbol of the national economy results in a number of casualties, economic loss, social fear and damage to national status. That's why high-rise building has also emerged as a target of major terrorist attacks, compared to other types of buildings. We have 54 high-rise buildings in 15 regions over the country. The Ministry of Land, Infrastructure and Transport and Seoul Metropolitan Government have offered the guidelines to prevent terrorist attacks toward high-rise buildings. Since the 9/11 terrorist attacks, the U.S. Federal Emergency Management Agency (FEMA) has developed and taken advantage of the Risk Management Manual Series. According to this manual, pre-assessment is conducted for the prevention of terrorism and particularly in FEMA 455, risk of the surrounding areas, vulnerability, possibility from terrorist attacks are checked. After the check, experts classify the risk of terrorist attacks toward the high-rise buildings and according to the risk classification, architects, security experts and structure engineers can carry out terrorism prevention program for high-rise buildings. The U.K. NaCTSO has also offered the terrorism prevention guidelines. Therefore, the Ministry of Land, Infrastructure and Transport and Seoul Metropolitan Government should make more concrete guidelines for high-rise buildings such as what U.S. FEMA and U.K. NaCTSO implement, including prior evaluation technique for terrorism risk.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.211-220
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• 2020

High-quality computed tomography (CT) images enable precise lesion detection and accurate diagnosis. A lot of studies have been performed to improve CT image quality while reducing radiation dose. Recently, deep learning-based techniques for improving CT image quality have been developed and show superior performance compared to conventional techniques. In this study, a super-resolution convolutional neural network (SRCNN) model was used to improve the spatial resolution of CT images, and image quality according to the hyperparameters, which determine the performance of the SRCNN model, was evaluated in order to verify the effect of hyperparameters on the SRCNN model. Profile, structural similarity (SSIM), peak signal-to-noise ratio (PSNR), and full-width at half-maximum (FWHM) were measured to evaluate the performance of the SRCNN model. The results showed that the performance of the SRCNN model was improved with an increase of the numbers of epochs and training sets, and the learning rate needed to be optimized for obtaining acceptable image quality. Therefore, the SRCNN model with optimal hyperparameters is able to improve CT image quality.

• Journal of Chest Surgery
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• v.31 no.1
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• pp.1-6
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• 1998

Total body water is increased after cardiopulmonary bypass resulting in tissue edema and organ dysfunction. Ultrafiltration has been used to reduce this accumulation of water. We have carried out a prospective randomized study in 17 children undergoing open heart surgery, comparing modified ultrafiltration(MUF) with nonfiltered controls. MUF was carried out for about 10 minutes after completion of cardiopulmonary bypass to a hematocrit 36∼42%. Blood loss, blood transfused, hemodynamics, and laboratory data were recorded for 24 hours postoperatively. The results were analyzed using Mann-Whitney U test, comparing controls(n=7) to ultrafiltered(n=10). There was no death in each group. The mean filtrate volume(ml/kg) was 42(30∼68). Blood loss(ml/kg/24hr) was 14.5 mean(4.0∼26.6) in controls versus 12.1 mean(6.0∼21.5) in MUF(P＞0.05) ; blood transfused(ml/kg/24hr) was 9.4 mean (6.0∼36.3) in controls versus 3.4 mean(0∼11.4) in MUF(P<0.05). There was rise in arterial blood pressure during MUF. Percent rise of systolic blood pressure was 4.2(0∼11.7) in controls versus 19.8(7.0∼36.9) in MUF(P=0.001). Percent rise of diastolic blood pressure was 10.0(1.6∼20.8) in controls versus 30.6(5.8∼73.3) in MUF(P<0.05). Platelet count, fibrinogen, and oncotic pressure rose after MUF. No complications directly attributable to the ultrafiltration were observed. Conclusively, MUF is safe, effective means of removing body water and beneficial to hemodynamics.

• Journal of Korean Elementary Science Education
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• v.18 no.2
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• pp.65-77
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• 1999

The purpose of this study was to find out the effectiveness of metacognitive instruction model on the changes of science concepts, when it was applied to 6th grade students. To do this, students were tested with the achievement of molecules and molecular motion concepts and metacognitive self-regulation test as a pretest Based upon metacognitive instruction model and student's conception, instruction program were developed. This metacognitive strategy Program was applied to the experimental group and expository teaching was applied to the comparison group (followed the order and method in authorized science textbook and teachers handbook). When planned lessons were finished, students were given a post-test to find conceptual change. After six months students were given a test again to find retention effect. There was a significant difference in conceptual change and retention between comparison group and experimental group by treatment at p< .05 level, The difference between comparison group and experimental group was especially significant, when the situation of test item wasn't similar to that of the textbook Metacognitive instruction model was more effective to high group than low group in metacognitive self-regulation level on conceptual change and retention. So the metacognitive strategy Played an important role in conceptual change and retention. And we can recognize that the students who take part in the metacognitive lesson can apply the corrected concept to the other concrete situation because they can understand new concept accurately by metacognitive strategies. And we can guess that high group in metacognitive self-regulation level can team metacognitive strategy easily but relatively low group student have some trouble in learning new strategy.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.67-75
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• 2015

This research is to investigate the four years growth mountain-cultivated ginseng ripened twenty-two weeks into four years fermented persimmon vinegar (tentatively: Sansamcho) ingestion on obese-related factors during dietary control. The Sansamcho was ingested orally, two times a day, after every meal for six weeks to the male rats. Groups were divided into the control (CON), the restricted diet (RD), and the weight cycling (WC). And, each groups has its own sub-groups as the -control (-CON), 2.5 times diluted Sansamcho ingestion (-MPV2.5), and 5.0 times diluted Sansamcho ingestion (-MPV5.0) groups, respectively. The number of rat was consisted of seven in each group. After six weeks rearing periods was done, abdominal fats (retroperitoneal fat, mesentery fat, and epididymal fat) and energy metabolic-related protein (AMPK: AMP-activated protein kinase; PPAR-${\alpha}$: peroxisome proliferator-activated receptor-${\alpha}$; and CPT-1: carnitine palmitoyltransferase-1) were weighed and analyzed. Amount of stored fat was significantly or tended to decrease by Sansamcho ingestion. In addition, sum of fats increasing were suppressed by the material. On the contrary, energy metabolism-related protein expression was significantly increased or tended to increase by Sansamcho ingestion. This results suggested that increased energy metabolism using Sansamcho was restrained effectively visceral fat store by high-fat diet and/or dietary control. In other words, it has a good function to suppress weight cycling which is the most insoluble problem. Therefore, the fusion material, Sansamcho, may expect to utilize as the obese-suppression-food.