• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.380-380
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• 2019

본 연구에서는 일반 상호보완이론(Generalized Complementary Relationship, GCR)을 활용하여 실제증발산량을 추정하고, 추정한 실제증발산량기반 가뭄지수로부터 미국 전역에 대한 가뭄을 해석하는 것이다. 월강수량, 최고 최저기온, 이슬점온도 등의 필요한 기상자료는 Parameter-elevation Relationships on Independent Slopes Model(PRISM)으로부터 수집하였으며, 1981년부터 2015년까지 총 35년의 미국 전역에 대한 실제증발산량을 추정하였다. 대상지역의 유역평균 강수량과 유출량의 차(P-Q)와 North American Land Data Assimilation System(NLDAS-2) Noah 지표모형(Land surface models)으로 산정한 실제증발산량과 비교 검증하였다. GCR로부터 증발산 부족량(ET Deficit, ETD)을 산정하고 이를 표준정규화하여 미국 전역에 대해 Standardized Evapotranspiration Deficit Index(SEDI)를 산정하였다. 본 연구로부터 GCR 기반 실제증발산량은 P-Q의 값과 상관계수가 0.94로 매우 높은 상관성을 보였으며, NLDAS-2 Noah모형의 실제증발산량보다 다소 크게 추정하는 경향을 보였다. SEDI와 Standard Precipitation Index(SPI)의 상관성은 지속시간이 클수록 더 크게 나타났다. 증발산 상호보완이론활용 실제증발산기반 SEDI이 강수자료를 사용하지 않고서도 적절한 가뭄해석에 이용될 수 있을 것으로 판단된다.

• Korean Journal of Materials Research
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• v.30 no.12
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• pp.655-659
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• 2020

Hydrogen isotopes (i.e. deuterium and tritium) are supplied to the tokamak in the International Thermonuclear Experimental Reactor (ITER) fuel cycle. One important part of the ITER fuel cycle is the recycling of unused fuel back to the tokamak, as almost 99 % of fuel is unburned during fusion reaction. For this, cryogenic distillation has been used in the isotope separation system (ISS) of ITER, but this technique tends to be energy-intensive and to have low selectivity (typically below 1.5 at 24 K). Recently, efficient isotope separation by porous materials has been reported in the so-called quantum sieving process. Hence, in this study, hydrogen isotope adsorption behavior is studied using chemically stable ZIF-11. At low temperature (40 K ~ 70 K), the adsorption increases and the sorption hysteresis becomes stronger as the temperature increases to 70K. Molar ratio of deuterium to hydrogen based on the isotherms shows the highest (max. 14) ratio at 50 K, confirming the possibility of use as a potential isotope separation material.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.9
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• pp.77-86
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• 2018

Demand for construction technology is expected to change due to changes in domestic and foreign construction markets and the fourth industrial revolution. In particular, demand for project management strategy and project management capability is even more increasing rather than existing production technology capability. However, the current re-education program for engineers and technicians in construction industry is not matching the need of improving capacity required to reflect the demand of construction technology from construction industry. Therefore, in this study, as a part of efforts in innovating the current global construction talent re-education system to cope with the change in the construction industry, we analyzed the difference between the demand of construction technology and the present condition of construction re-education program. In order to investigate the current status of re-education of construction, questionnaires were prepared to gather opinions from construction engineers who attended construction re-education program and also from industrial partners that are jointly doing business. This study can be an example to improve the construction re-education program as a system for substantially reinforcing the competence of engineers rather than those programs that are merely verifying and/or extending engineers' certification.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.11
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• pp.163-170
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• 2019

Most of the current crack investigation work consists of visual inspection using simple measuring equipment such as crack scale. These methods involve the subjection of the inspector, which may lead to differences in the inspection results prepared by the inspector, and may lead to a large number of measurement errors. So, this study proposes an image-based crack detection method to enhance objectivity and efficiency of concrete crack investigation. In this study, YOLOv2 was used to determine the presence of cracks in the image information to ensure the speed and accuracy of detection for real-time analysis. In addition, we extracted shapes of cracks and calculated quantitatively, such as width and length using various image processing techniques. The results of this study will be used as a basis for the development of image-based facility defect diagnosis automation system.

• Korean Journal of Metals and Materials
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• v.49 no.7
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• pp.577-582
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• 2011

The newly developed ${\alpha}-case$ controlled mold material for Ti investment castings was suggested in this research. The $Al_2O_3$ mold containing interstitial $TiO_2$ and substitutional $Ti_3Al$ was manufactured by the reaction between $Al_2O_3$ and Ti. It is obvious that as the $TiO_2$ and $Ti_3Al$ content in the mold surface were increased, the depth of the interfacial reaction was significantly reduced. In addition, substitutional $Ti_5Si_3$ in the mold surface owing to the reaction between Ti and $SiO_2$ from the binder was effective for ${\alpha}-case$ reduction. Therefore, the ${\alpha}-case$ reduction was accomplished by the diffusion barrier effect of interstitial $TiO_2$, substitutional $Ti_3Al$ and $Ti_5Si_3$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.231-239
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• 2021

There are six species of pinnipeds in Korean waters. Because of the lack of research on pinnipeds, it has been difficult to obtain ecological information on each species. All six species have been designated as endangered species, marine protected species, or national monuments by the government, depending on historical records. In this study, the current status of pinnipeds in Korea was investigated through reviewing the literature, and sighting and bycatch records, with the intention of providing new information for the review of the six species. Spotted seals and northern fur seals are well known inhabitants of Korea. The southern part of the East Sea is thought to be the margin of the distribution of Steller sea lions. Sightings of ribbon seals and ringed seals were not confirmed in Korean waters. Sea lions have not been seen since their last sighting on Dokdo in 1951 and are thought to have become extinct after that. It is necessary to delist undistributed or extinct species in Korea from the marine protected species list.

• Journal of Sasang Constitutional Medicine
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• v.32 no.4
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• pp.141-151
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• 2020

Objectives This study aimed to report significant improvement of dizziness, gait disturbance and dysarthria after treatment with Sasang constitutional medicine treatment on a Taeeumin patient with olivopontocerebellar atrophy. Methods A 53-year-old female diagnosed olivopontocerebellar atrophy about one year ago suffered from dizziness, gait disturbance and dysarthria. The patient was identified as Taeeumin Joyeol pattern and treated with Cheongsimyeonja-tang and Taegeuk acupuncture. The patient's main symptoms were observed using Global Assessment Scale (GAS) during the treatment period. In addition, the Unified Multiple System Atrophy Rating Scale (UMSARS) was used to assess the overall function of patient. Results We observed a significant improvement in symptoms of dizziness, gait disturbance and dysarthria using GAS, and UMSARS score decreased in Part I and II. Conclusions This case showed that Sasang constitutional medicine treatment can be effective treatment for Taeeumin patient with olivopontocerebellar atrophy. We consider that consistent treatment can contribute to improve the patient's quality of life.

• Journal of Sasang Constitutional Medicine
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• v.33 no.4
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• pp.32-42
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• 2021

Objectives The purpose of this case study was to report a patient with Post COVID-19 syndrome treated with Seunggeumjowi-tang based on Sasang Constitutional Medicine. Methods The patient was hospitalized after being diagnosed with COVID-19 and was suffering with post from COVID-19 syndrome such as fatigue and loss of appetite after discharge. The patient was diagnosed as Taeeumin and treated with Seunggeumjowi-tang. The progress was evaluated with the global assessment scale (GAS). Results and Conclusions Fatigue and anorexia were significantly improved, and other symptoms were restored as before. This case shows the possibility of Sasang Constitutional medication treatment for the sequelae of COVID-19.

• Korean Journal of Materials Research
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• v.31 no.8
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• pp.465-470
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• 2021

Deuterium is a crucial clean energy source required for nuclear fusion and is a future resource needed in various industries and scientific fields. However, it is not easy to enrich deuterium because the proportion of deuterium in the hydrogen mixture is scarce, at approximately 0.016 %. Furthermore, the physical and chemical properties of the hydrogen mixture and deuterium are very similar. Therefore, the efficient separation of deuterium from hydrogen mixtures is often a significant challenge when using modern separation technologies. Recently, to effectively separate deuterium, studies utilizing the 'Kinetic Quantum Sieving Effect (KQS)' of porous materials are increasing. Therefore, in this review, two different strategies have been discussed for improving KQS efficiency for hydrogen isotope separation performance using nanoporous materials. One is the gating effect, which precisely controls the aperture locally by adjusting the temperature and pressure. The second is the breathing phenomenon, utilizing the volume change of the structure from closed system to open system. It has been reported that efficient hydrogen isotope separation is possible using these two methods, and each of these effects is described in detail in this review. In addition, a specific-isotope responsive system (e.g., 2nd breathing effect in MIL-53) has recently been discovered and is described here as well.

• Journal of the Korean Society of Safety
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• v.37 no.6
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• pp.25-31
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• 2022

In this study, the spill and leak system is developed to provide real-time remote monitoring of industrial complexes where chemical accidents have been occurring every year. The spill and leak monitoring system uses IR-RCD equipment mounted on a 70m-high steel tower to detect chemical substances, thereby detecting chemical accidents such as leaks, fires, and explosions in real time. If IR-RCD equipment can actually detect chemical substances at a long distance, accurate and rapid initial response can be expected. Therefore, in order to confirm that IR-RCD equipment can detect chemical leakage accidents occurring at a long distance, acetone was selected as the experimental substance and a detection experiment was designed. The experiment was conducted using the acetone pool evaporation method at the wharf which was located 1.5 km away from IR-RCD equipment, and it was confirmed whether IR-RCD equipment could detect acetone in real time through the control monitor.