• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.288-291
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• 2011

최근 아스팔트 혼합물의 배합설계법은 기존에 주로 사용하던 빔 및 마샬 배합설계법에서 수퍼페이브 배합설계법으로 점차적으로 바뀌고 있는 추세이다. 수퍼페이브의 배합설계과정에서 중요한 사항 중의 하나는 선회다짐기를 사용하는 다짐방법이다. 아스팔트 포장은 노상 위에 보조기층, 기층, 표층의 순으로 구성되는데 노상은 포장 아래 약 1.0 m의 흙부분으로 포장과 일체로 구성되며 포장체에 작용하는 하중을 최종적으로 지지하는 층이다. 따라서, 수퍼페이브 배합설계법에서 사용하는 선회다짐기를 포장과 일체로 구성되는 노상의 다짐시험에도 적용한다면 각각의 포장층에 같은 원리의 다짐방법을 적용한다는 큰 의미가 있을 것으로 판단된다. 본 논문에서는 일반 노상토에 시멘트와 플라이애시를 첨가한 강화노상토를 선회다짐기를 이용하여 시편을 제작하였고, 각 시편에 대한 탄성계수를 1축압축시험, 공진주시험, LFWD를 이용해 각각 측정하여 각 결과물들의 상관관계를 추정하고자 한다.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.44-48
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• 2008

With extracts from Cheongmoknosang, anti-inflammatory effect was examined in LPS-stimulated Raw 264.7 cells. LPS (10 ng/ml) treatment increased the production of inflammatory cytokines, $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ but the ethanol extracts from Cheongmoknosang slightly decreased the production of $TNF-{\alpha}$ and also reduced the expression of iNOS and the production of COX-2. It seems that anti-inflammatory effects of ethanol extracts from Cheongmoknosang is partly due to the inhibition of iNOS and COX-2 expression by inhibiting nuclear translocation of $NF-{\kappa}B$ and AP-l in Raw 264.7 cells.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.161-168
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• 2003

평판재하시험은 재하시험시 표층의 매우 잘 다져진 곳에 대한 지지력 계수를 획득하여 실다짐도를 과대 평가하는 결과를 초래할 수 있다. 이에 착안하여 응력도달 범위가 작은 평판재하시험을 지양하고 콘관입시험으로부터 획득되는 노상의 관입지수로부터 지반의 다짐도를 추정할 수 있는 콘관입시험기와 구동시스템 및 해석 프로그램을 개발하였다.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.85-98
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• 2009

The in-situ Compaction test using sand cone (RC) and Plate Bearing Capacity Test (PBT) has been widely used for evaluating the subgrade and subbase condition on the pavement system. However, because the in-situ RC and PBT test are expensive and take plenties of time for operation, these are very difficult to figure out the in-situ characteristics of subgrade and subbase strength in detail. Therefore, for faster and economical operation, this study is to compare the Light Falling Weight Tests and propose the LFWD test as the in-situ Compaction test. This study suggests the relationship between in-situ RC value, $K_{30}$, $M_R$ and $E_{LFWD}$ of the subgrade and subbase materials in Korea using the laboratory and in-situ testing.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.27-34
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• 1968

상수의 엽면적은 상엽의 수획량 즉 수량과 높은 상관관계가 있고 그의 간이측정법은 매우 의의 깊은 일이므로 상전에서 생체대로 엽면적을 측정할 수 있도록 간이측정법을 고안하였다. 우리나리 상수의 주요품종인 개량서반, 일지뢰, 노상 그리고 수원 제4호의 4개품종을 재료로 절위별로, 지조별로 엽면적과 엽장, 최대엽폭과의 관계를 조사 실험하였으며 공시 엽수는 개량서반 741문, 일지뢰 853문, 노상 507문, 수원제4호 441문, 도합 2,542문이었다. 5개열엽으로 엽형이 비슷한 개량서반과 일지뢰의 2개품종의 엽면적은 (엽장$\times$최대엽폭)$\times$0,643, 단엽인 노상과 수원제4호의 2개품종의 엽면적은 (엽장$\times$최대엽폭)$\times$0,735에 의해서 구할 수 있음을 알았다. 즉 개량서반과 일지뢰는 엽장에 최대엽폭을 곱한 적에 계수 0.634를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 높은 상관관계를 보였고 이때의 상관계수의 평균을 개량서반에 있어서는 r=0.931, 일지뢰에 있어서는 r=0.960이었다. 노상과 수원상4호는 엽장에 최대엽폭을 곱한 적에 계수 0.735를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 또한 높은 상관관계를 보였고 이때의 상관계수의 평균을 개량서반에 있어서는 r=0.931, 일지뢰에 있어서는 r=0.960이었다. 노상과 수원상 4호는 엽장에 최대엽폭을 곱한 적에 계수 0.735를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 또한 높은 상관관계를 보였고 이 때의 상관계수 r의 평균을 노상에 있어서는 r=0.999, 수원상 4호에 있어서는 r=0.996이었다. 이 방법에 의하면 시간과 노력을 크게 절감시킬 수 있을 뿐만 아니라 생체대로 쉽게 엽면적을 구할 수 있는 이점이 있다.

• International Journal of Highway Engineering
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• v.12 no.3
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• pp.71-77
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• 2010

Anti-freezing layer does not used in case of non frost heaving in subgrade soils. In this case, the modulus of subgrade soils were varied with freezing and thaw cycles under non frost heaving. That effect should be properly considered in pavement design. Impact resonance test that is nondestructive testing method was used for continuously determining the modulus of subgrade soils during freezing and thaw cycle. The modulus of subgrade soils was identical with freezing and thaw cycles under closed freezing and thaw system which is no water supplement into specimen during testing. There was also no difference in the modulus of subgrade soil between before and after freezing-thaw cycles for all specimens with different water content and density. That is thaw-weakening of subgrade soils do not occur under closed freezing and thaw system. The moduli at freezing conditions are varied with water content and density, but it can be ignored in practical design sense.

• International Journal of Highway Engineering
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• v.11 no.4
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• pp.17-23
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• 2009

Deformational characteristics of subgrade soils are very important input parameters for pavement design. It is necessary to make an amount of effort to estimate experimentally the modulus of subgrade soils. In case of designing simple (or lower level) pavement section, the estimation of the modulus based on experiments must cause an excessive cost. It has proposed various empirical correlation models to estimate the modulus from basic properties of the materials or more simple alternative tests. Seven subgrade soils in Korea were tested in this study. It was founded that the deformational characteristics of subgrade soils in Korea has a close relation to strength characteristics, the empirical correlation model was proposed. There was a close relation between cohesion value and modulus at low confining stress ($r^2=0.93$). By comparing with the measured modulus and the modulus determined by proposed correlation model from strength characteristics, the value of the coefficient of determination ($r^2$) is 0.75.

• Journal of Digital Convergence
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• v.18 no.8
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• pp.69-83
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• 2020

The purpose of this study is to classify the types of street parking in low-rise residential areas. First of all, prior research was reviewed to examine the background of occurance and the process of change of low-rise residential areas. and derive factors that affect the street environment. Next, based on the selection criteria, the residential area of Bangi 2-dong, Songpa-gu was selected as the site of the case and the status analysis was conducted on streets, buildings, and on-road parking. The summary of the results is on-road parking usually occurs on residential streets where social consensus is difficult to reach, suggesting that alternatives to on-road parking in residential areas are needed. Based on the results of the previous analysis, street types were classified considering the characteristics of streets, structures and street parking. Then, the characteristics of each type of street were analyzed and implication for improving the street environment were suggested. In addition, the results of the classification of street types confirmed that different street parking occurred depending on the width of the street and the use of the lower floors, even if it was the same area, and that a solution was needed accordingly.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.141.2-141.2
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• 2009

• International Journal of Highway Engineering
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• v.5 no.2 s.16
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• pp.37-47
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• 2003

The basic study was performed on the mechanical analysis of frost and heave using program FROST by CRREL, U.S. army corps of engineers. The characteristics of frost heaving in pavement was analyzed by considering climate, pavement sections and subgrade soil conditions in Korea. Water tables were located at the depth of 0.35m, 2m and 3.35m from subgrade. Inputs were evaluated inevitably from the existing references. As a result frost heave and depth were evaluated with respect time. Maximum frost heave decreased lowering the water table and maximum frost depth was less than 15cm from subgrade. Frost action did not affect seriously on the analysis sections.