• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.2
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• pp.68-76
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• 2022

This study was performed to investigate the mechanism of the change in compressive strength of autoclave cured geopolymers. Specimens were immerged in distilled water, 2M, 8M, and 14M alkaline solutions for 3, 7, and 21 days. The change in the specimens immersed in a short period of time was not significant, but the compressive strength of the specimens immersed in the distilled water and 8M alkali solution) for 21 days increased more than twice as much as before immersion because of additional geopolymerization. However, compressive strength decreased due to the alkaline aggregate reaction when alkaline solution was supplied more than a certain level of concentration. Therefore, immersing the specimens for more than 21 days in the distilled water or 8M alkaline solution would be desirable for the improvement of compressive strength of autoclave cured specimens.

• Korean journal of aerospace and environmental medicine
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• v.24 no.2
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• pp.21-27
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• 2014

We aimed to study about the effect of acute hyper-gravity (HG) on the allergic immune response in a murine model of allergic asthma. Thirty-two BALB/c mice were used. In Group A (control group, n=8), mice were sensitized and challenged with saline. Group B (HG control group, n=8) were exposed to HG (10 Gz, 1 hour) after intraperitoneal and intranasal saline challenge. Group C (asthma group, n=8) received intraperitoneal and intranasal ovalbumin (OVA) challenge. Group D (HG asthma group, n=8) were exposed to HG after intraperitoneal and intranasal OVA challenge. We evaluated serum total and OVA-specific IgE; serum titers of cytokines; and histopathologic examination of lung. As a result, titers of Serum total and OVA-specific IgE were not significantly different between groups. Compared to Group C, mice in Group D showed significant increase of Th2 cytokines (IL-4, IL-13), cytokines involved in eosinophilia (IL-3, IL-5, GM-CSF) and those involved in cell-medicated immunity (IFN-γ). In histopathologic examination, lungs of Group D showed significantly more infiltration of inflammatory cells compared to Group C. However, these differences were not so significant between Groups A and B. In conclusion, acute HG could exacerbate allergic asthma in experimental animals.

• Journal of Creative Information Culture
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• v.5 no.3
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• pp.285-293
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• 2019

As the 2015 Revised Secondary Information Curriculum was reorganized into a software-focused curriculum, a number of information teachers were needed. For this purpose, a special training course for multiple majors for secondary information teachers was established, and produced about 100 teachers with multiple majors. To improve this training program, this study surveyed the trainees joined in this program. As the result of the survey, there were findings that the short training period made it difficult to understand the overall content of the curriculum, and that they had a loss of learning due to the burden on another major. Therefore, long-term training is necessary to train informatics teachers, and by realizing the reinforcement of specialty through pre-training and main training, and by organizing a gradual curriculum, substantiality should be sought.

• The Journal of Korean Obstetrics and Gynecology
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• v.22 no.3
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• pp.197-204
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• 2009

Purpose: Obesity is the major risk factor of the heart disease and the metabolic disease. And many obese women have dysfunction of the endocrine system. There are many reports about oriental obesity treatment program. In clinics, the electroacupuncture with exercise is believed more effective. But the difference of weight loss as exercise and women was not studied. Methods: The subjects were 75 young women who visited Kangnam Kyunghee hospital for obesity management from March 2006 to July 2008. Six treatments had performed, the weight loss checked at every treatment. 52 women treated by oriental obesity treatment with exercise, 23 women treated therapy without exercise. As the exercise and the age, the weight loss was compared. Results: The weight loss of electroacupuncture with exercise was higher than that of electroacupuncture without exercise, but was not significant. The weight loss of perimenopausal women was significantly low. Conclusion: The comparison of electroacupuncture with exercise and electroacupuncture without exercise was not significantly different. The weight loss of the older women would be less than the weight loss of the younger.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.332-332
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• 2021

도시화가 상당히 이뤄지고 기습적인 폭우의 발생이 불확실하게 나타나는 시점에서 재산 및 인명피해를 야기할 수 있는 내수침수에 대한 위험도가 증가하고 있다. 내수침수에 대한 예측을 위하여 실측강우 또는 확률강우량 시나리오를 참조하고 연구대상 지역에 대한 1차원 그리고 2차원 수리학적 해석을 실시하는 연구가 오랫동안 진행되어 왔으나, 수치해석 모형의 경우 다양한 수문-지형학적 자료 및 계측 자료를 요구하고 집약적인 계산과정을 통한 단기간 예측에 어려움이 있음이 언급되어 왔다. 본 연구에서는 위와 같은 문제점을 해결하기 위하여 단일 도시 배수분구를 대상으로 관측 강우 자료, 1, 2차원 수치해석 모형, 기계학습 및 딥러닝 기법을 적용한 실시간 홍수위험지도 예측 모형을 개발하였다. 강우자료에 대하여 실시간으로 홍수량을 예측할 수 있도록 LSTM(Long-Short Term Memory) 기법을 적용하였으며, 전국단위 강우에 대한 다양한 1차원 도시유출해석 결과를 학습시킴으로써 예측을 수행하였다. 침수심의 공간적 분포의 경우 로지스틱 회귀를 이용하여, 기준 침수심에 대한 예측을 각각 수행하였다. 홍수위험 등급의 경우 침수심, 유속 그리고 잔해인자를 고려한 홍수위험등급 공식을 적용하여 산정하였으며, 이 결과를 랜덤포레스트(Random Forest)에 학습함으로써 실시간 예측을 수행할 수 있도록 개발하였다. 침수범위 및 홍수위험등급에 대한 예측은 격자 단위로 이뤄졌으며, 검증 자료의 부족으로 침수 흔적도를 통하여 검증된 2차원 침수해석 결과와 비교함으로써 예측력을 평가하였다. 본 기법은 특정 관측강우 또는 예측강우 자료가 입력되었을 때에, 도시 유역 단위로 접근이 불가하여 통제해야 할 구간을 실시간으로 예측하여 관리할 수 있을 것으로 판단된다.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.307-312
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• 2023

North Korea has already been using underground space for military purposes for decades, and is currently developing it as a key base for operating asymmetric forces. Accordingly, the special operations teams need fighting methods, weapon systems, and organizational structures to carry out subterranean operations. This paper presents an unmanned system platform for subterranean operations that combines tilt-rotor type drones, high-tech sensors, communication repeaters, and small robots, and a system that can be operated by special operation teams. Based on this, the survivability of the special operations teams can be strengthened and operational utility can be maximized. Afterwards, if Special Warfare Command collects collective intelligence based on the ideas related to subterranean operations presented in this paper and further develops these, it will be possible to drive subterranean operations doctrines, weapon systems, and organizational structures optimized for the battlefield on the Korean Theater of Operations in the near future.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.253-257
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• 2022

The Azerbaijani Armed Forces(AAF) that carried out a drone blitzkrieg for a short time defeated the Armed Forces of Armenia in 2020. As a result, the AAF proved that drones aren't supplementary means, but major ones in combat. Simultaneously, the AAF demonstrated that middle powers can shortly implement the revolution in military affairs(RMA) if the organizational culture for deep change are backed up. Especially, the AAF's RMA is full of suggestions to the Repulic of Korea Army(ROKA) because the ROKA wants to prepare the dronbot combat system for the future. After this, the ROKA is able to visualize how to perform the korean style drone blitzkrieg achieving a intact victory if its comabt system and structure are developed at the same time.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3A
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• pp.209-216
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• 2009

The structural stability as well as economical efficiency of the wind sensitive structures are strongly dependant on accurate evaluation of the design wind speed. Present study demonstrates a useful wind data obtained at the wind monitoring tower in the Kwangyang Suspension Bridge site. Moreover the Measure-Correlate-Predict (MCP) method has been applied to estimate the long-term wind data at the bridge site based on the wind data at the local weather station. The measured data indicate that the turbulent intensities and roughness exponents are strongly affected by the wind direction and surrounding topography. The new design wind speed based on MCP method is 20m/s lower than that at the original estimation, and the resulting design wind load is only 36% of the old prediction. The field measurement of wind data is recommended to ensure the economical and secure design of the wind sensitive structures because the measured wind data reveal much different from the estimated one due to local topography.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.283-296
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• 2011

The aim of this study is to analyze the short-term changes of beach and dune morphology at Hwajin beach, Korea using by terrestrial LIDAR. Based on ArcInfo as point cloud obtained through precise analyzing studying area twice (1st : Sep 1. 2010, 2nd : Oct 2nd. 2010) by terrestrial LIDAR, alteration of beach and dune was analyzed at DEM, of which cell size is about 10cm. Consequently, during the studying period, coastlines at studying area moved backward and reduced the area of coastal zone. In a section change, the north beach moved backward with more eroded beach face and the middle section of south beach moved forward with more deposited beach face. Considering all the section changes of beach at studying area, beach section during the 1st measurement period can be defined as a summer profile, and it can be explained that the temporary storm profile was formed by the strong wave created during studying period. As a result of analyzing the alteration of beach area by terrestrial LIDAR, alteration of narrow area was able to be analyzed in detail by class of 'centimeter' and the time was able to be shortened.

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.53-63
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• 2011

The changes and causes of channel section in Naeseongcheon River, a tributary of Nakdong River, during the long(1984~2001) and short(2009~2011) periods are analyzed. There are the declines of channel height with a maximum of approximately 2m in the most areas of the lower reaches during the past 20 years. These are thought as the influences of active aggregate collections and river dredging. The size of sand bar within the channel at the NM1 decreases greatly during the past 2 years. This may results from the decrease of sediment supply due to the Yeongju Dam construction in the upper reaches. However, the NM2 and NL2 where the natural channel are preserved experience the slight increase of height during the past 2 years. Therefore, the anthropogenic channel interferences in Naeseongcheon River have greatly influenced on the declines of channel height by the decrease of sediment supply.