• Journal of the Korea Institute of Building Construction
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• v.9 no.4
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• pp.63-73
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• 2009

Recently, the use of lightweight panels in building structures has been increasing. Of the various lightweight panel types, styrofoam sandwich panels are inexpensive and are excellent in terms of their insulation capacity and their constructability. However, sandwich panels that include organic material are quite vulnerable to fire, and thus can numerous casualties in the event of a fire due to the lack of time to vacate and their emission of poisonous gas. On the other hand, lightweight foamed concrete is excellent, both in terms of its insulation ability and its fire resistance, due to its Inner pores. The properties of lightweight concrete is influenced by foaming agent type. Accordingly, this study investigates the insulation properties by foaming agent type, to evaluate the possibility of using light-weight foamed concrete instead of styrene foam. Our research found thatnon-heating zone temperature of lightweight foamed concrete using AP (Aluminum Powder) and FP (animal protein foaming agent) are lower than that of light-weight foamed concrete using AES (alkyl ether lactic acid ester). Lightweight foamed concrete using AES and FP satisfied fire performance requirements of two hours at a foam ratio 50, 100. Lightweight foamed concrete using AP satisfied fire performance requirements of two hours at AP ratio 0.1, 0.15. The insulation properties were better in closed pore foamed concrete by made AP, FP than with open pore foamed concrete made using AES.

• Journal of the Korea Institute of Building Construction
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• v.24 no.2
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• pp.273-284
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• 2024

This study investigates the impact of international oil price fluctuations on overseas construction orders secured by domestic and foreign companies. The analysis employs statistical data spanning the past 20 years, encompassing international oil prices, overseas construction orders from domestic firms, and new overseas construction orders from the top 250 global construction companies. The correlation between these variables is assessed using correlation coefficients(R), determination coefficients(R²), and p-values. The results indicate a strong positive correlation between international oil prices and overseas construction orders. The correlation coefficient between domestic overseas construction orders and oil prices is found to be 0.8 or higher, signifying a significant influence. Similarly, a high correlation coefficient of 0.76 is observed between oil prices and new orders from leading global construction companies. Further analysis reveals a particularly strong correlation between oil prices and overseas construction orders in Asia and the Middle East, potentially due to the prevalence of oil-related projects in these regions. Additionally, a high correlation is observed between oil prices and orders for industrial facilities compared to architectural projects. This suggests an increase in plant construction volumes driven by fluctuations in oil prices. Based on these findings, the study proposes an entry strategy for navigating oil price volatility and maintaining competitiveness in the overseas construction market. Key recommendations include diversifying project locations and supplier bases; utilizing hedging techniques for exchange rate risk management, adapting to local infrastructure and market conditions, establishing local partnerships and securing skilled local labor, implementing technological innovations and digitization at construction sites to enhance productivity and cost reduction The insights gained from this study, coupled with the proposed overseas expansion strategies, offer valuable guidance for mitigating risks in the global construction market and fostering resilience in response to international oil price fluctuations. This approach is expected to strengthen the competitiveness of domestic and foreign construction firms seeking success in the international arena.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.178-178
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• 2011

도로소음은 다양한 소음원에 의해 발생하며, 도로를 이용하는 사람과 도로 주변사람에게 큰 불편을 초래한다. 보다 쾌적한 환경을 원하는 현대인에게 있어 도로 소음의 경감은 중요한 환경 공해로 작용한다. 도로 소음을 줄이기 위해서는 여러 가지 방법이 있을 수 있으며, 이 중 도로 포장의 개선을 통해 도로 소음을 경감할 수 있으며, 이와 같은 포장을 저소음 포장이라고 한다. 저소음 포장은 주행하는 차량의 타이어와 노면이 마찰하면서 발생하는 소음을 최소화하기 위한 것으로 소음 발생의 메커니즘을 바탕으로 하고 있다. 저소음 포장중 가장 널리 사용되고 있는 방법은 공극을 늘리는 것이다. 약 20%의 공극은 타이어와 노면 사이의 에어펌핑음을 최소화 하며, 소리를 흡수하는 역할로 약 3dB의 소음 가소 효과가 있는 것으로 알려져 있다. 소음을 감소시키는 또 하나의 방법은 노면의 표면 조직을 매끈하게 하여 타이어와 노면의 충격음을 줄이는 방법이다. 노면의 평탄성을 개선하기 위해 포장에 사용되는 골재의 최대크기를 줄이는 소입경 포장을 소음 가소의 목적으로 유럽 등지에서 많이 사용되고 있다. 본 연구에서는 이와 같은 저소음 기능을 위해 공극률을 크게 하고 소입경 골재를 사용하는 소입경 저소음 포장의 현장 적용을 위한 배합 설계를 수행하였다. 소입경 저소음 포장의 최대 골재 크기는 현장 적용성과 경제성을 고려하여 10mm 골재를 사용하였으며, 수도권에서 입수한 4곳의 산지 골재를 분석하여 골재 합성 입도를 산정하였다. 10mm 저소음 포장의 골재 입도 범위는 공극률 15~18%를 목표로 하며, 이를 만족하기 위하여 배합 설계를 수행한 결과 5mm 통과 중량 백분율이 약 30%로 하는 개립도가 적당한 것으로 나타났다. 공극이 증가함에 따라 포장의 내구성 향상을 위해 사용된 고점도 바인더는 아스팔트 혼합물의 생산 및 시공온도를 증가시키게 된다. 또한 굵은골재의 비율이 높은 개립도 아스팔트 혼합물의 경우 운반과정과 포설 과정에서 온도가 빨리 떨어지는 단점이 있다. 이를 극복하기 위하여 중온 첨가제의 사용을 통해 생산 및 다짐온도를 낮추고자 하였다. 소입경 저소음 포장의 배합설계 과정은 배수성 포장의 배합설계 과정과 유사하나, 칸타브로 손실률과 흐름실험의 변곡점을 기준으로 할 경우, 칸타브로 손실률과 흐름 손실률이 매우 작아 변곡점을 판단하기 어렵기 때문에 칸타브로 손실률과 흐름 손실률의 기준 만족 여부로 판별하고, 최적 아스팔트 함량은 공극률을 기준으로 산정하는 것이 바람직할 것으로 판단된다. 중온 첨가제를 사용할 경우는 중온 첨가제로 인한 점도의 변화를 감안하여 혼합 및 다짐 온도를 결정하고 배합 설계를 수행하며, 중온 첨가제의 특성과 양에 따라 최적 아스팔트 함량이 변화하게 된다.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.192-199
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• 2009

This study was conducted to find proper structural reinforcement methods for the 4.5m-high (eaves height) 1-2W type plastic greenhouse. 3D finite element analysis was used to analyze the steel-tube structure. The 4.5m-high 1-2W type plastic greenhouse was modified by welding 1.5m-long steel-pipes into a 3.0m-tall columns of the standard 1-2W type plastic greenhouse. This remodeling method is widely used in Korea with farmer's discretion to increase the production when they grow paprika. But it is not based on the quantitative structural analysis. The proposed reinforcement methods were proved to stand against the design wind velocity of $40m{\cdot}s^{-1}$ and snow depth of 40cm. It strongly implies that the cross beam between side columns and wind resistance walls, and the lattice type cross beam should be good reinforcements to improve the structural safety of the elevated eaves height plastic greenhouse.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.215-215
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• 2011

1996년도 UN해양법협약의 발효와 각국의 배타적 경제수역(EEZ) 선포로 연안역에 대한 관심이 국제적으로 고조되고 있는 가운데 우리나라에서도 연안역 관리법(가칭)이 제정되었다. 국토해양부는 연안역 공간이용 효율성 극대화와 부존 해양자원의 치계적인 개발과 보전을 위하여 연안역 관리법을 특별법으로 제정하였으며 1998년 중에 시행령 등 하위법령을 제정해 시행키로 하였다. 이 이후로도 연안역 특별법에 대한 연구는 계속 진행중이며, 현제 연안역은 연안어업, 수산양식장, 모래채취, 염전, 해수욕장, 관광지, 해양시설, 간척, 매립지, 공업단지 등으로 많이 이용되고 있다. 그러나 연안역 안전시설에 대한 상세 설계기준 및 시공에 대해서는 자세히 다루고 있지 않다. 연안역은 관광객이 증가하면서 안전시설과 구난장비의 미비한 실정으로 인해 인적 물적 피해가 빈번히 발생 증가하고 있는 것으로 나타나고 있다. 안전사고의 다발지역을 분석해 보면 관광객으로 인하여 방파제 주변에서의 안전사고가 증가하고 있는 상황이며, 이로 인한 인명피해도 증가하고 있다. 방파제에 대한 안전사고를 막기 위하여 우선적으로 방파제에 대한 안전사고를 해결하고자 인명피해를 막는 구난시설들에 대한 간격 등의 기준을 제시하였다. 다른 지역에 비하여 연안역은 파도에 의하여 사람이 떠내려가는 것을 고려하여 구난시설의 간격을 해안이나 다른 안전시설에 비하여 더 짧게 하였으며, 구난시설이 피해자에게 빠르게 전달되고자 멀리 던진 수 있으며, 구난시설을 잡음과 동시에 숨을 쉴 수 있는 여건이 조성되도록 연구하였다. 안전사고를 효율적으로 방지하기 위하여 인간공학을 접한 안전시설을 연구를 하였다. 인간공학이란, 인간의 행동, 능력, 한계, 특성 등에 관한 정보를 발견하고, 이를 도구, 기계, 시스템, 과업, 직무, 환경의 설계에 응용함으로 인간이 생산적이고 안전하며 쾌적하고 효과적으로 이용할 수 있도록 하는 것이다. 인간공학은 인간이 사용할 수 있도록 설계하는 과정에 있어 인간의 활용성 및 편리성을 증대하는 학문으로 보며, 설계초기 단계에서부터 인간의 요소의 체계적인 고려를 필요로 하게 되었다. 이 논문은 과거에 일어났던 사고사례들을 주시하면서 앞으로의 미래에 똑같은 사고사례가 발생하지 않도록 예방하이 위하여 인간공학과 안전시설을 통하여 연안역의 안전시설의 설치기준에 도움이 되는 자료를 제공하고자 한다.

• Journal of the Korean Institute of Gas
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• v.26 no.1
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• pp.7-19
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• 2022

Hydrogen purification is generally performed through chemical and physical methods. Among various types of purification method PSA(Pressure Swing Adsorption) is widely used with its purification capacity and economic efficiency. In Korea, most of the hydrogen used in automobiles and power generation fuel cells is purified using PSA. Hydrogen produced in petrochemical complexes has difficulties in transportation. The government is planning to install hydrogen extractors that produce hydrogen directly from consumers in connection with the city gas supply chain, and companies are also installing related research and demonstration facilities one after another. Europe and others have recently established safety standards related to PSA and are making efforts for systematic safety management at the construction and operation stage, but domestic safety standards related to PSA are still insufficient. This study aims to identify problems of existing facilities through surveys and risk assessment by companies operating existing PSA, and to prepare domestic technical standards including them in overseas technical standards to promote the safety of new and existing PSA systems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.229-236
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• 2006

Recently, the use of crushed sand produced by the crushing of stone is continuously increasing to reach an utilization rate of about 20% of the whole fine aggregates that is foreseen to grow larger in the future. However, the lack of recognition concerning quality during the production of crushed sand results in the use of crushed sand that do not satisfy the KS F 2527 standard during the manufacture of concrete. And, studies investigating the effects of such crushed sand on concrete are still neglected. Therefore, this study intends to provide data that can be exploited for concrete using crushed sand through the analysis of the effects of the grain shape of crushed sand on the quality of concrete. Results revealed problems in the workability, air entraining and durability for a value of 53% for the solid volume percentage for shape determination specified by the current KS F 2527. Analysis showed that the adjustment of the solid volume percentage for shape determination from the currently specified 53% to 55% will improve the quality of concrete using crushed sand in high strength concrete particularly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6336-6343
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• 2014

The aim of this study was to consider new 3D printing techniques and how to use them in architecture, compare the 3D printing and current techniques, and analyze them economically. 3D printing technology is expected to result in considerable changes to the entire system, such as production and distribution using this new technology in the near future. In addition, architecture is expected to follow this trend. This study examined how to take advantage of 3D printing technology in construction to prepare for a new architectural trend of 3D printing technology in the future. This study examined the 3D printing technology that is used in buildings and the current state of 3D printing technology. In addition, the 3D printing technology and current technology was also compared, and analyzed economically. 3D printing technology is the step before the stage of practical use. On the other hand, the commercialization of 3D printing technology makes it possible to reduce the cost compared to the current method. Furthermore, as the technology is developed in the future, the cost is expected to be reduced further. Therefore, the use of 3D printing technology in architecture is expected increase continually.

• Journal of the Korea Institute of Building Construction
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• v.14 no.2
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• pp.156-162
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• 2014

This study aims to develop a rapidly hardening type of concrete to achieve the removal of form intensity (more than 10MPa) using the method of curing at room temperature in order to solve some economic environmental problems by omitting the steam curing process involved in producing PC (Precast Concrete). Therefore, this study evaluated a rapidly hardening cement containing a high amunt of C3S, which is very responsive in expressing early intensity, and a rapidly hardening type of concrete which uses some hardening accelerator to increase thehydration reaction of $C_3S$. The results of the experiment on concrete using some hardening accelerator are asfollows. In the slump flow experiment for identifying the liquidity and the air test, the desired values were met. The compression strength showed rapid expression response by 12 hours, and met the desired value within 6~9 hours. Its drying shrinkage value and Autogenous shrinkage value were measured as below ($-754.5{\times}10^{-6}$),and satisfied the requirements. In addition, in the Semi-Adiabatic Temperature Test, it was found that the concrete rose to its peak temperature within 24 hours and then its temperature dropped.

• Korean Educational Research Journal
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• v.42 no.1
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• pp.1-34
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• 2021

The thesis tries to compare The Structure of World History with Anti-Oedipus in the textual context, and to re-compare in the educational context. I mean by the education an event which contrasts starkly with an essence. It adopts 5W1H, a general reporting form of an accident or event, as the distinctive features at twice comparisons. The purpose of the thesis is not evaluative but interpretive comparison. In the textual context, the thesis discusses, 1) as WHAT, the use of Marx from Kant vs. Nietzsche's point of view, 2) as WHO, the actual subjects of the exchanging human vs. the productive machine, 3) as WHEN/WHERE, the society of the modes of exchange vs. the modes of inscription, 4) as HOW, the revolutionay means of the simultaneous revolution of the world vs. the schizophrenic process, 5) as WHY, the ideal subjects of the associative human vs. the non-human of liberation of desire. In the educational context, the thesis discusses, 1) in the WHAT as educational way, autonomous morality vs. active power, 2) in the WHO as the affirmity of actual subjects, that of the ideal idea vs. that of real power, 3) in the WHEN/WHERE, as the in-between time-space of education, the incommensurable communicative situation of humans vs. the conflictive of machines, 4) in the HOW, as the educational method of achieving the ideal, the involuntary restoration of the already-had ideal vs. the now-have completion and break-through of the schizophrenic process, 5) in the WHY, as the aim of education, cosmopolitan vs. overman.