• 한국위성정보통신학회논문지
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• 제8권4호
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• pp.130-134
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• 2013

본 논문에서는 3D 방송의 기본적인 원리를 설명하고 3D 방송을 CS 기술을 적용하여 데이터 용량을 줄이는 방식을 제안한다. 샘플링 이론과 CS 기술의 차이점을 설명하고 개념과 동작원리를 설명한다. 최근 제안된 CS 센싱의 복원 알고리즘인 AMP(Approximate Message Passing)와 CoSaMP(Compressive Sampling Matched Pursuit)를 소개하고 이를 이용하여 이미지 데이터를 압축 복원하여 비교한다. 두 알고리즘의 계산시간을 비교하여 낮은 복잡도를 갖는 알고리즘을 판단한다.

• 한국위성정보통신학회논문지
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• 제10권3호
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• pp.57-61
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• 2015

본 논문에서는 3D 방송의 기본적인 원리를 설명하고 실감영상 CS 기술을 적용하여 데이터 용량을 줄이는 방식을 제안한다. 샘플링 이론과 CS 기술의 차이점을 설명하고 개념과 동작원리를 설명한다. 압축 센싱의 복원 알고리즘인 SS-CoSaMP(Single-Space Compressive Sampling Matched Pursuit) 와 AMP(Approximate Message Passing)를 소개하고 이를 이용하여 이미지 데이터를 압축 복원하여 비교한다. 계산시간을 비교하여 낮은 복잡도를 갖는 알고리즘을 판단한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.447-450
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• 2005

The purpose of this study is to investigate properties of compressive strength of concrete using the shale rock as coarse aggregates. To evaluate properties of compressive strength of concrete using crushed shale rock, we performed the expriment according to the proportioning strength of $10MPa\~40MPa$ and the slupm of $12\%\~15\%$. The result of this study is as follow. The compressive strength of concrete using crushed shale rock is lower than those of granite aggregates. The proportioning strength is higher, the reduction of comperssive strength of concrete using the shale rock is higher.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.285-288
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• 2003

The compressive strength of concrete is used as the most fundamental and important material property when reinforced concrete structures are designed. It has been problem to use this value, however, because the control specimen sizes and shapes are different from every country. In this study, the effect of specimen shapes and sizes on compressive strength of concrete members was experimentally investigated based on fracture mechanics. Experiments for the mode I failure was earned out by using cylinder, cube, and prism specimens. The test results are curve fitted using least square method(LSM) to obtain the new parameters for the modified size effect law(MSEL). The analysis results show that the effect of specimen sizes and shapes on ultimate strength is apparent. The results also show stronger size effect in member when the casting direction is perpendicular to loading direction

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.24-25
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• 2016

In this study, the thermal strain of high strength concrete with the compressive strength of 80, 130, 180MPa were measured under 25% of compressive strength loading condition. As results, it is considered that decline of the elastic modulus and shrinkage strain of high strength concrete become grater at the elevated temperatures.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.214-215
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• 2017

Extreme loads such as impact and explosion have higher strain rate than static loading condition. Therefore, it is necessary to evaluate mechanical properties at high strain rate in order to apply fiber reinforced cement composites to ensure safety performance against impact and explosion. In this study, the compressive properties of fiber reinforced cement composites by strain rate were evaluated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1267-1272
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• 2000

When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and strength development may be delayed. These are problems on cold weather concrete. One of the solution methods for resolving these problems has been to reduce the freezing temperature of concrete by the use of chemical admixtures called Accelerators for freezing resistance. Therefore, in this study, we executed freezing temperature of mortar, setting and strength properties with using water reducing accelerator and accelerators for freezing resistance which are producted internationally. As a result of this experiment, the freezing temperature of mortar is lower and the setting property is promoted when the admixing content of accelerators for freezing resistance is increased. Moreover, the compressive strength of mortar used accelerators for freezing resistance represented the result which is similar with result of analysis of compressive strength increase with using logistic curve formula, but in the case of plain and using water reducing accelerator, there is no relation between logistic curve formula, maturity and compressive strength.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.105-108
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• 2005

This study investigated fundamental properties of the recycled aggregate which was produced through recent hi-techniques of recycling. In addition, the mechanical properties of the concrete that used the recycled aggregate were compared to the concrete used the natural aggregate. From the results of the mechanical property tests, as the recycled aggregate replacement ratio increased, the compressive strength and elastic modulus decreased. When the recycled aggregate completely replaced the natural aggregate, the compressive strength and elastic modulus was about 15$\%$ and 35$\%$ lower than the natural aggregate concrete, respectively. Based on the test results, equations for prediction of compressive strength and elastic modulus were suggested in the consideration of the amount of the replaced recycled aggregate. Based on the test results and study, the equation predicting the required development length of the recycled aggregate concrete is proposed.

• Advances in nano research
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• 제5권2호
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• pp.99-111
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• 2017

Nano particles have been gaining increasing attention and applied in many fields to fabricate new materials with novel functions due to their unique physical and chemical properties. In the present study two nano materials, namely nano silica (NS) and nano clay metakaolin (NMK) were partially replaced with ordinary Portland cement (OPC). The replacement level was varied from 0.5 to 2.0% in OPC and blended in cement mortar with a water cement ratio of 0.40. Mechanical property studies and durability experiments such as compressive strength, tensile strength, water absorption, depth of chloride penetration test. Nano silica was synthesized from rice husk ash and analyze the size using particle size analyzer. The results indicate that the compressive and tensile strength of the cement mortars containing nano materials were higher strength compared to the plain mortar with the same water cement ratio.

• 화약ㆍ발파
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• 제28권2호
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• pp.59-68
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• 2010

도심지에서의 건물해체 및 발파공사로 노후된 인접 구조물의 구조적 안정성에 영향을 미칠 가능성이 있다. 본 연구에서는 노후 콘크리트 재료의 물성을 파악하기 위하여 반발경도에 의한 압축강도와 X선 회절 및 상 분석에 의한 성분 함량으로 상관성을 비교하였고, 충격 에너지에 의한 손상도 평가를 위해 측정된 탄성파속도 값으로 손상도를 산출하였다. 결과적으로, 반발경도에 의한 압축강도와 재료의 성분 함량은 상관성이 있음을 확인하였고, 탄성파속도 값으로 산출된 손상도는 압축강도가 큰 재료일수록 작게 나타났고, 충격력이 작을수록 작게 나타났다.