• Journal of the Korean GEO-environmental Society
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• v.18 no.7
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• pp.5-12
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• 2017

The surface of the tunnel lining issues various problems such as cracks due to the cold weather. It is necessary to reduce the recovery costs by means of developing new recovery techniques. However, the research on reducing the damage of road tunnel lining caused by cold weather has not actively been conducted. Hence, this paper analyzes the effectiveness of using insulating materials such as aerogel and heat insulating liquid in enhancing insulating capability. The results show that these materials are effective in reducing heat transfer, confirming damage reduction in cold weather.

• Journal of the Korean Society for Railway
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• v.20 no.1
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• pp.99-110
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• 2017

As a part of several Eurasian initiatives, the Korean government is trying to reconnect railways through North Korea to the Asian continent. If South Korea could build a network using railway, it would be a chance to develop a robust economic environment and to motivate economic growth. In the railway reconnection project between North and South Korea, the most important part of the railway roadbed sector is repair or improvement, and then construction of a new line through North Korea. There are not many big differences in the geological conditions; however, climate condition varies greatly during winter. The most significant condition in the safety of railway operation is frost-heaving. However, since South Korea has a relatively mild climate condition compared with North Korea, design and construction specifications under severe weather conditions in winter have not been prepared. This study proposes a plan for revising the railway design standard for underpass structures through an analysis of international standards, leading to site construction to prevent frost-heave.

• KOREAN POULTRY JOURNAL
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• v.40 no.12
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• pp.138-141
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• 2008

매년 호흡기 질병의 발생상황은 기후와 밀접하게 연관되어 있다. 이것은 계사 외부온도가 떨어지면서 계사 내의 절대 환기량이 적어짐으로 인해 생기는 공기의 질저하가 질병이 발생하는데 있어 매우 깊은 관계가 있음을 의미한다. 계군에 대한 모니터링을 연중 실시하다 보면 계군에 발생하는 ND나 LPAI와 같은 호흡기 질병의 발생경향을 읽을 수 있다. 2008년 여름은 어느 해보다 길었고 가을 날씨는 최근 몇 년간의 상황과는 매우 다르게 높은 온도를 오랫동안 기록하였다. 온도가 비교적 높은 최근 몇 개월간의 기후 덕에 질병 발생의 정도가 경미하게 나타났다. 계사의 온도가 높게 유지되면서 환기량이 많아 뚜렷한 임상증상(호흡기 증상, 산란율저하)이 없이 내과하는 형태로 질병이 진행되고 전국적으로 ND나 LPAI 등의 발생이 없는 것처럼 보일 수밖에 없었던 것이다. 호흡기 질병의 발생은 외 기온도와 계사 내의 환기량과 밀접하게 연관되어 있다. 결론적으로 매년 발생하는 호흡기성 질병의 대부분은 환기량 부족에 따른 공기질의 저하가 가장 큰 원인 중의 하나라고 해도 과언이 아니다. 올 가을까지의 기후가 질병이 잘 발생하지 않는 상황을 낳았다 하더라도 이제 12월에 접어들면서부터는 계사온도가 당연히 낮아질 수밖에 없고 그로 인한 환기량의 저하에서 오는 호흡기 질병의 발생은 필연적이라 할 수 있다. 따라서 농장에서 체계적인 환기관리를 실시하면 계군에서 발생하는 호흡기 질병을 억제하거나 피해를 현저하게 줄일 수 있다. 이달의 질병관리 포인트로 세심한 환기관리를 제시하고 몇 가지 경험적 사항을 기술하고자 한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.98-99
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• 2020

The objective of the study is to investigate the compressive strength of damaged part by early frost damage and sound part of the concrete placed when exposed to a low temperature of -20℃ for 24 hours in normal concrete. Test results indicated that the compressive strength of damaged part was 14.5 MPa lower than that of sounf part due to early frost damage.

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.80-88
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• 2015

In the case of those types of work that are performed outdoor construction work, many non-working days occur due to climatic elements such as low temperature, rainfall, and high wind velocity. In particular, damage incurred construction delays hardly decreases because weather forecasting has become difficult due to global warming. In the present study, time points of drastic changes in annual average temperatures, annual average maximum temperatures, and annual average minimum temperatures were identified through BCP analysis and increasing/decreasing trends of non-working days in summer and winter were compared and analyzed on the basis of the change points. According to the results of the study, annual average temperatures drastically changed in 1988 and 1998. After the two time points, non-working days in summer and winter clearly showed increasing trends and decreasing trends respectively.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.136-146
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• 1999

A series of experiments were carried out in winter to investigate the indoor thermal environment in greenhouses with different kinds of heating systems, and characterize the energy consumption, heat transport and thermal energy efficiency of each system. By the Quantitative calculation of heat losses which transmit through the covers of greenhouse, the fundamental data of energy-saving of the particular heating system were obtained. And from the analysis of air temperature differences between indoor and outside, it was possible to select more effective energy-saving and comfortable heating system in greenhouses. The electric heater was more stable in thermal environment and cheaper in cost, since it could be used during the surplus time of electric power from 10：00 p.M. to 8：00 A.M. But the low air temperature in greenhouses besides these times resulted in a chilling problem of the crops. The heating system by hot air had the advantage to show nearly uniform temperature difference by the height above the ground. But the system had the disadvantage to require more energy consumption than the electric heating system.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1417-1424
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• 2018

The damage caused by foot-and-mouth disease and AI has been repeated in year by year, and the actual damage is held by farmers. Currently, domestic livestock farmers' demand for foreign labor force is rapidly increasing, but the foreign management system is very inadequate, autonomous disinfection consciousness is poor and seasonally disinfest of winter is a serious situation. Thus, the exit management system, where small and medium scale farmers can purchase and install, is necessary for medium and small scaled farmer who is suffering from the pollutants and who does not have capacity to install expensive sterilization. In this paper, we propose ICT fusion combined plasma access control system which can utilize the principle of low temperature plasma lamp, to introduce disinfection system, to ensure convenience and safety that enables integrated control.

• Journal of the Korean GEO-environmental Society
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• v.20 no.4
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• pp.17-21
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• 2019

In the cold region, the frozen damages in highway tunnels and regular road tunnels have widely been investigated and reported, but the measurement has not been sufficient made. The average temperature in cold region is below the zero, resulting in that the damage due to freezing at the entrance/exit of tunnel is more severe than in the middle of tunnel. In this study, a heating element was developed to prevent the tunnel lining from being frozen by enforcing to increase the temperature of tunnel lining. Then field tests using the developed heating element were performed and it was ensured that the temperature of tunnel lining increased after a certain time.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.118-125
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• 2011

This study was conducted to check danger of the cold injury by reviewing the lowest temperature by regions and the cold tolerance of Lagerstroemia indica and Pyracantha angustifolia. The cold tolerance of the samples treated at low temperature was evaluated by measuring electrical conductivity and observing browning of the cambium. It was proved that the lethal temperature of L. indica is below $-17.1^{\circ}C$, and that of P. angustifolia is below $-18.9^{\circ}C$. The frequency of the lowest temperature went down below $-17.1^{\circ}C$, was 7 times in Daejeon, 55 times in Cheongju and 72 times in Suwon for the last 45 years. In Daejeon, it has happened only once since 1975. The temperature dropped below $-18.9^{\circ}C$ 45 times in Cheongju and 32 times in Suwon during the same period, but it has not happened at all since 1991. It appears that the rising coefficient of the lowest temperature increases, as the latitude gets higher. As a result, L. indica and P. angustifolia which were planted in the central region of Korea, are considered in danger from freezing injury because the temperature can get very low intermittently in winter. But, the risk of freezing has reduced gradually as the lowest temperature raises each year.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.957-972
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• 2018

Tunnels constructed in cold regions can cause serious defects such as cracks and leaks due to external temperature changes in the portals and vents. In order to prevent the freezing damage of the tunnel, appropriate measures should be applied to the section where the freeze damage is concerned. However, the specific criteria and contents for judging whether or not the anti-freeze measures are applied are not presented. In this study, the laboratory freezing tests on the temperature changes of the concrete specimens under freezing conditions were carried out. And the freeze-thaw repetition cycle (F), which can judge the possibility of freezing damage, were presented based on the heat transfer quantity (W) by experimental results of case studies. Also, we propose a classification of cold regions considering the climatic characteristics of Korea for using it to efficient design and maintenance.