• Journal of the Korean GEO-environmental Society
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• v.20 no.1
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• pp.51-56
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• 2019

This paper presents a method to deice concrete pavement with carbon nanotube(CNT) as an heating material so as to avoid the adverse effects of conventional deicing method such as salt on the structure, function and environment. To this end, laboratory tests integrated with numerical simulations were conducted. In the laboratory tests, the CNT was embedded inside the concrete slab and generated the heat up to the target temperature of $60^{\circ}C$ in the freezer at temperature of $-10^{\circ}C$. Then, the surface temperature was measured to investigate how far the heat transfers on the surface at temperature of above $0^{\circ}C$. Also, three different spacings of 15, 20 and 30cm between CNTs were conducted to determine the maximum allowable spacing of CNT. Along with these experimental tests, heat transferring analysis conducted to validate the test results.

• Economic and Environmental Geology
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• v.54 no.3
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• pp.389-397
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• 2021

Moryang Fault is geomorphologically observed as a linear fault valley from Angang through Moryang, Duckhyun and Wondong to Gimhae, and contacts with Yangsan Fault, being obliquely away to the east, at Angang disrict. The fault valley appears a V-shape feature with a width from 100 to 300 m, and has fragmental zones of the fault along the valley on a small scale. Nine fault-outcrop localities were found along the nine-kilometers valley between Daehyun-ri, Gyeongju, and Baenaemi-gogae, Yangdong-ri, Ulsan. The fault strikes the North-North-East to the Northeast and dips to the Northwest with high angles, and reveals it had been undergone predominantly sinistral reverse fault movement sense, left-lateral and right-lateral strike-slip sense in bedrocks. However, after unconsolidated sediments, there was the top-up-to-the-east dextral reverse fault movement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.10
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• pp.1188-1194
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• 2019

Among the many ways to measure the flow of fluid the hot air wind speed sensor is a device for measuring the speed or temperature by heat transfer of a fluid. However, the hot wire wind speed sensor is sensitive to external environmental factors, and has a disadvantage of inaccuracy due to ambient temperature, humidity, and signal noise. In order to compensate for this disadvantage, advanced technology has been introduced by adding temperature compensation circuits, but it is expensive. In order to solve this problem, this paper studies the wind speed sensor that does not need temperature compensation. Heated wind speed sensors are very vulnerable to the ambient temperature, which is generated by electronic circuits, even among external environmental factors. in order to improve this, the auxiliary heating element is additionally installed in the heating element to control a constant temperature difference between the auxiliary heating element and the heating element.

• Journal of Advanced Navigation Technology
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• v.25 no.1
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• pp.60-67
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• 2021

Countries around the world, including the U.S. are actively researching to commercialize the logistics services using drones. In Korea, telecommunications companies as well as logistics companies are researching and developing the logistics services using drones. However, there's an environmental difference for last-mile delivery between the U.S. and Korea. In Korea, more than 77% of the population lives in apartments and the population density is the 4th highest in the world. Accordingly, in terms of the logistics services using drones, it is necessary to research it with the Korean suitable environment. In this paper, a precision positioning method of drone last-mile delivery in urban areas using short-range wireless communication and barometer is proposed. The experiment results show that the proposed method can detect a window within 2.5 meters. It is expected that the proposed method will help improve the logistics services using drones in urban areas.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.469-476
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• 2022

This study developed a Recurrent Neural Network model implemented through Long Short-Term Memory (LSTM) that generates long-term tidal level data at Busan Port using tide observation data. The tide levels in Busan Port were predicted by the Korea Hydrographic and Oceanographic Administration (KHOA) using the tide data observed at Busan New Port and Tongyeong as model input data. The model was trained for one month in January 2019, and subsequently, the accuracy was calculated for one year from February 2019 to January 2020. The constructed model showed the highest performance with a correlation coefficient of 0.997 and a root mean squared error of 2.69 cm when the tide time series of Busan New Port and Tongyeong were inputted together. The study's finding reveal that long-term tidal level data prediction of an arbitrary port is possible using the deep learning recurrent neural network model.

• Journal of the Korea Institute of Building Construction
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• v.21 no.6
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• pp.629-640
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• 2021

According to statistics from the Ministry of Land, Infrastructure and Transport in 2018, approximately 37% of residential buildings in Korea need to be reconstructed. Due to the rapid growth of the demolition industry, many side effects such as environmental destruction and safety accidents are becoming a problem in the demolition of existing buildings. This study proposes a decision-making process for selecting the most suitable dismantling method for field application by comprehensively considering safety, economic feasibility, and environmental characteristics. In particular, field applicability is evaluated by evaluating risk factors for the selected method. To this end, this study proposes the TOPSIS method for the selection of the dismantling method using the QFD development concept, and the FMEA method as a continuous development process of the selected method.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.33-33
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• 2022

팔당댐 유역은 수도권 2600만 인구의 상수원으로, 수도권 전체 물 소비량의 90.2%에 달하는 물을 공급하고 있어 중요성이 상당히 크다. 하지만 기후변화로 한반도에 극한기후의 발생 빈도가 증가하면서 미래 수자원 관리가 더욱 어려워질 전망이다. 이에 본 연구에서는 모형 구축을 통해 기후변화가 팔당댐 유역의 수자원에 미치는 영향을 정량적으로 평가하고자 하였다. 본 연구는 저수량이 높은 다목적댐이자 상류에 위치하는 소양강댐, 충주댐의 유역의 유입량을 수문모형인 VIC model로 모의하였다. 댐의 존재에 따른 하류의 유량 교란을 고려하기 위해 딥러닝 기반의 LSTM 예측 모형을 활용하였고 각 댐의 방류량을 예측하였다. 보정 기간(1986-2019), 검증 기간(2020)에 대한 방류량 예측 모형의 NSE는 0.9407, 0.6449로 높은 예측성능을 보였다. 팔당댐 유입량 예측에도 LSTM이 활용되었고 소양강댐, 충주댐의 방류량과 두 유역을 제외한 잔여유역의 기상변수인 강우량, 온도, 풍속이 입력되었다. 팔당댐 유입량 예측 모형의 NSE는 보정 기간(1986-2019), 검증 기간(2020)에 대해 각 0.9990, 0.7878로 유입량을 정확도 높게 예측하였다. 기후변화의 영향을 평가하기 위해 기상청에서 제공하는 RCP4.5의 상세화된 고해상도(1km) 미래 기상자료를 구축된 모형에 입력하여 미래의 팔당댐 유입량을 모의하였다. 모의 결과, 미래 기간에는 팔당댐 일 유입량의 변동성이 증가하면서 유황이 불안정해지고 극한에 해당하는 빈도 갈수량이 크게 감소하는 것으로 예측되었다. 따라서 극한기후로 인해 물 공급이 제한되는 재난 상황에 대비하여 물 공급에 대한 자립성을 높일 수 있는 새로운 물관리 정책이 필요할 것이다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.391-399
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• 2008

Because of relatively high temperature, over $240^{\circ}C$, of asphalt for steel deck bridge during pavement procedure, the temperature of deck could rise over $100^{\circ}C$ and undesirable excessive displacement and thermal stress could occur. In this study, in order to estimate the thermal effect of pavement process and to find the optimal pavement process, a new thermal analysis technique with Equivalent Heat Source (EHS) is proposed and its applicability to the practical pavement of steel bridge is studied. EHS is developed to simulate the high temperature pavement materials and its thermal effect such as conduction and convection which cannot be explain easily in general structural analysis program for bridge design. To verify the applicability of new analysis technique with EHS, thermal analyses of steel deck bridge with uplift and curved bridge with various pavement procedures are presented.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4A
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• pp.587-596
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• 2006

A half portion of Korean railway bridges depends on the type of steel plate girder bridge. Since these bridges have been built in the early stage of Korean economical boom, numerous maintenance effort suffers from aging and progressive degradation issues at present. In accordance with these efforts, this paper would like to address the detailed analyses of thin steel plates with bolts in order to simulate the connection regions of steel plate girder bridge. The fundamental modal analysis, transient dynamic analysis with 3D piezoelectric element in open circuit loop and signal process with aids of TOF(time of flight) and WC(wavelet coefficient) are extensively discussed.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.962-974
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• 1998

Background: Alteration of p53 tumor suppressor genes is most frequently identified in human neoplasms, including lung carcinoma. It is well known that bcl-2 oncoprotein protects cells from apoptosis. Recent studies have demonstrated that bcl-2 expression is associated with favorable prognosis for patients with non-small cell lung carcinoma. However, the precise biologic role of bcl-2 in the development of these tumors is still obscure. p53 and bcl-2 have important regulatory influence in the apoptotic pathway and thus their relationship is of interest in tumorigenesis, especially lung cancer. Purpose: The author investigated to know the prognostic significance of the expression of p53 and bcl-2 in radically resected non-small cell lung cancer. Method: 84 cases of formalin-fixed paraffin-embedded blocks from resected primary non-small cell lung cancer from 1980 to 1994 at Hanyang University Hospital were available for both clinical follow-up and immunohistochemical staining using monoclonal antibodies for p53 and bcl-2. Results : The histologic classification of the tumor was based on WHO criteria., and the specimens included 45 squamous cell carcinomas(53.6%), 28 adeonocarcinomas(33.3%) and 11 large cell carcinomas(13.1 %). p53 immunoreactivity was noted in 47 cases of 84 cases(56.0%). bcl-2 immunoreactivity was noted in 15 cases of 84 cases(17.9%). The mean survival duration was $64.23{\pm}10.73$ months in bcl-2 positive group and $35.28{\pm}4$. 39 months in bcl-2 negative group. The bcl-2 expression was significantly correlated with survival in radically resected non-small cell lung cancer patients(p=0.03). The mean survival duration was $34.71{\pm}6.12$ months in p53 positive group and $45.35{\pm}6.30$ months in p53 negative group(p=0.21). The p53 expression was not predictive for survival. There was no correlation between combination of the different status of p53 and bcl-2 expression in our study. Conclusions : The interaction and the regulation of new biologic markers, such as those involved in the apoptotic pathway, are complex. bcl-2 overexpression is a good prognostic factor in non-small cell lung cancer and p53 expression is not significantly associated with the prognostic factor in non-small cell lung cancer.