• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.75-76
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• 2015

This study has examined the impact resistance and blast resistance characteristics of HPFRCC as a research on impact resistance and blast resistance characteristics using high volume mortar and high velocity projectile for evaluating the protection performance of actual buildings as small quantity experiment of laboratory conditions is performed although there was an instance of performing research on mortar that has reinforced fiber followed by the rise of problems on the damage of human life and buildings created due to explosion and shock. As a result, the destruction loss area and depth have decreased in case of the surface compared to the rear side. As tensile strength and tenacity have increased with the increased fiber replacing ratio, a tendency of destruction loss area and depth getting decreased was shown as the impact resistance has increased.

• 한국안전학회지
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• 제38권1호
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• pp.34-41
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• 2023

In this study, S food manufacturing business located in Chungbuk was selected as the subject, and the transition in insulation resistance in major electrical equipment used in this food manufacturing business was analyzed for 4 years (2018-2021). It was confirmed that the insulation resistance decreased over time for all 18 electrical facilities. Insulation resistance changed due to environmental influences such as load characteristics and ambient temperature. Particularly in the case of the food manufacturing industry, it was confirmed that the decrease started after 2 years, although it varied depending on equipment and environmental influences. Furthermore, it was confirmed that management through predicting the management cycle of electrical equipment is possible by deriving a regression equation through regression analysis of insulation resistance measurement values.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.339-344
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• 2005

A person's body resistance in the waterpark, public bath and similar places is lower than any other places due to effect of water. So low voltage may create a shock hazard for the human body in case of leakage or fault currents from lighting unit etc. We researched the related regulations these are internal standards, NEC, IEC and investigated the actual conditions for the prevention of electrical shock due to lighting units in the waterpark, public bath and similar places. So we could present actual facilities's problems and solutions

• The Plant Pathology Journal
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• 제31권4호
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• pp.323-333
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• 2015

As sessile organisms, plants are exposed to persistently changing stresses and have to be able to interpret and respond to them. The stresses, drought, salinity, chemicals, cold and hot temperatures, and various pathogen attacks have interconnected effects on plants, resulting in the disruption of protein homeostasis. Maintenance of proteins in their functional native conformations and preventing aggregation of non-native proteins are important for cell survival under stress. Heat shock proteins (HSPs) functioning as molecular chaperones are the key components responsible for protein folding, assembly, translocation, and degradation under stress conditions and in many normal cellular processes. Plants respond to pathogen invasion using two different innate immune responses mediated by pattern recognition receptors (PRRs) or resistance (R) proteins. HSPs play an indispensable role as molecular chaperones in the quality control of plasma membrane-resident PRRs and intracellular R proteins against potential invaders. Here, we specifically discuss the functional involvement of cytosolic and endoplasmic reticulum (ER) HSPs/chaperones in plant immunity to obtain an integrated understanding of the immune responses in plant cells.

• 조명전기설비학회논문지
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• 제22권1호
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• pp.124-131
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• 2008

최근 도심지의 미관을 중요시함에 따라 전력설비의 지중화가 활발히 추진되고 있다. 지중선로의 분기나 접속을 인한 저압 지중함은 주로 사람의 통행이 빈번한 보도나 이면도로에 설치되어 있으며, 지중함 내 누전이 발생할 경우 행인이 감전될 위험이 있다. 더욱이 최근 기상이변으로 인한 폭우로 도로 침수가 자주 발생하고 있으며, 이러한 경우 인체는 물에 젓은 상태이므로 감전에 치명적일 수 있다. 본 논문에서는 저압 지중함에서 발생한 국내 외 감전사고사례의 원인과 점검결과를 분석하였으며, 분석결과 국내 외 감전사고의 사고원인은 통일하나 저압 지중함의 환경조건은 다른 것으로 나타났다. 향후 분석 자료는 저압 지중함에서의 감전사고를 방지하는데 활용필 수 있으며, 저압 지중함의 설치개선을 위한 기초 자료로 이용될 수 있을 것이다.

• International Journal of Concrete Structures and Materials
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• 제3권2호
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• pp.97-101
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• 2009

It has been known that acid-resistant concretes on the liquid glass basis have high porosity (up to 18${\sim}$20%), low strength and insufficient water resistance. Therefore they can not be used as materials for load-bearing structural elements. Significant increasing of silicate matrix strength and density was carried out by incorporation of special liquid organic alkali-soluble silicate additives, which block of superficial pores and reduces concrete shrinkage deformation. It was demonstrated that introduction of tetrafurfuryloxisilane additive sharply increases strength, durability and shock resistance of silicate polymer concrete in aggressive media. This effect is attributable to hardening of contacts between silicate binder gel globes and modification of alkaline component owing to "inoculation" of the furan radical. The optimal concrete composition with the increased strength, chemical resistance in the aggressive environments, density and crack resistance was obtained.

• 한국세라믹학회지
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• 제19권1호
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• pp.5-12
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• 1982

SiC-containing by-product from the surface abrasion process of porcelain cores is used as a starting material to develop the SiC-containing technical porcelain bodies. To prevent the bloating phenomenon of by-product specimen at firing temperature, it is acid treated. In order to enhance the workability and to lower the firing temperature of bodies, clay is added. Body containing 25% clay and 75% by-product fired at 135$0^{\circ}C$ showes extremely high thermal shock resistance and acid resistance.

• 대한기계학회논문집A
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• 제22권1호
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• pp.73-79
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• 1998

The development of a new material which should be continuously usable under severe environment of very high temperature has been urgently requested. The conventional thermal barrier coating(TBC) is a two layer coating, but a composition and a microstructure of functionally graded material(FGM) are varied continuously from place to place in ways designed to provide it with the maximum function of mitigating the induced thermal stress. The purpose of this study is to evaluate the heat-resistant characteristics by thermal shock of laser and furnace heating. The fracture behaviors of non-FGM(NFGM) and FGM were investigated based on acoustic emission(AE) technique during thermal shock test. Therefore, it can be concluded that FGM gives higher thermal resistance compared to NFGM by AE signal and fracture surface analysis.

• 대한기계학회논문집B
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• 제21권1호
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• pp.89-98
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• 1997

Compression waves propagating in a high speed railway tunnel impose large pressure fluctuations on the train body or tunnel structures. The pressure fluctuations can cause ear discomfort for the passengers and increase the aerodynamic resistance of trains. As a fundamental research to resolve the pressure wave phenomenon in the tunnel, a steady theory of Chester-Chisnell- Whitham was applied to a simple shock tube with a sudden cross-sectional area reduction to model trains inside the tunnel. The results of the present theoretical analysis were compared with the experiments of the shock tube. The results show that the reflected compression wave from the model becomes stronger as the strength of incident compression wave and the blockage ratio increase. However, the compression wave passing through the model is not strongly dependent on the blockage ratio. The theoretical results are in good agreement with the experiments.

• 대한기계학회논문집B
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• 제21권9호
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• pp.1139-1148
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• 1997

Compression waves propagating in a high-speed railway tunnel develops large pressure fluctuations on the train body or tunnel structures. The pressure fluctuations would cause an ear discomfort for the passengers and increase the aerodynamic resistance of trains. As a fundamental research to resolve the pressure wave phenomenon in the tunnel, experiments were carried out by using a shock tube with an open end. A blockage to model trains inside the tunnel was installed on the lower wall of shock tube, thus forming a sudden cross-sectional area reduction. The compression waves were obtained by the fast opening gate valve instead of a conventional diaphragm of shock tube and measured by the flush mounted pressure transducers with a high sensitivity. The experimental results were compared with the previous theoretical analyses. The results show that the ratio of the reflected to the incident compression wave at the sudden cross-sectional area reduction increases but the ratio of the passing to the incident compression wave decreases, as the incident compression wave becomes stronger. This experimental results are in good agreements with the previous theoretical ones. The maximum pressure gradient of the compression wave abruptly increases but the width of the wave front does not vary, as it passes over the sudden cross-sectional area reduction.