In this study, rear strain behavior of concrete panel considering the projectile nose shape was evaluated. It was considered that penetration and scabbing properties are different by each projectile nose shape. so it should be taken into account the rear strain behavior by projectile nose shape, when predicting scabbing, perforation of concrete by projectile impact.

Recently, an indirect displacement estimation method using data fusion of acceleration and strain (i.e., acceleration-strain-based method) has been developed. This paper proposes an improved displacement estimation method that can be applied to more general types of bridges by building the mapping using the finite element model of the structure. An experimental validation of the proposed method was carried out on a prestressed concrete girder bridge, and the method provides the best estimate for dynamic displacements.

본 논문에서는 IFS(iterated function system) 프랙탈에서 점의 코드를 활용한 변형의 개선 방법을 고려한다. 기존의 변형방법에서는 부분적 변형이 랜덤 반복에 의해 임의로 전파되므로 대개 단조로운 느낌을 주는 모양이 나타나고 있다. 이러한 점을 개선하기 위하여 코드를 활용 하여 맵의 선택을 제어하는 방법을 제안한다. 제안된 방법을 적용한 결과 프랙탈의 모양 특성 이 적절히 반영된 흥미로운 변형을 얻을 수 있었다. 또한 코드에 따라 변화하는 상태변수를 도 입하여 좌표의 변환 외의 다른 속성의 변형을 손쉽게 구현하는 방법도 제안한다.

Genetically modified (GM) pepper H15 containing the gene for cucumber mosaic virus (CMV) coat protein (CP) and its control line non-GM pepper P2377 were investigated for their allergic risk. Amino acid sequence of the inserted gene product CMV-CP was compared with those of known allergens. No known allergen had greater than 35% amino acid sequence homology over an 80 amino acid window or more than 8 consecutive identical amino acids. Protein patterns of GM and non-GM pepper extracts were evaluated by SDS-PAGE, which showed similar distribution of protein bands for both GM and non-GM pepper. Antigen-antibody reactions were compared between GM and its non-transgenic parental control. ELISA and immunoblot analysis of sera from allergic patients showed some IgE reactivity; however, no differences were observed between GM pepper H15 and P2377. We therefore conclude that CMV-CP is less likely to be an allergen; the protein composition and allergenicity of the GM pepper H15 is not different from that of P2377 and safe as a commercial host.

When the concrete is subjected to impact of the projectile, compressive stress wave is transmitted to the rear side. When the compressive stress wave reached the rear side, is was reflected as a tensile wave. And, when the tensile stress in the concrete matrix exceeded the dynamic tensile strength, crack in the concrete was occurred.

Conventional strain gauge can measure about 15~20% elongation. However, when the steel are ruptured, the strain at the necking region can be much higher than the measurement capacity of the conventional strain gauge. To measure the maximum strain at the necking region a new measurement technique should be developed. In this study, for this purpose image processing method for measuring 2-D strain distribution of tensile specimen of steel is proposed.

This research investigated the effects of matrix strength on the direct tensile behavior of high performance hybrid fiber reinforced cementitious composites (HPHFRCCs) at high strain rates. 3 different type matrixes were used (56 MPa, 81 MPa and 180 MPa). And macro fiber was long hooked fiber (H, =0.3 mm,=30 mm) and micro fiber was short smooth fiber (S, =0.2 mm,  =13 mm). The volume content of macro fibers was 1.0% and the volume content of micro fibers was 1.0%. The high matrix strength clearly increased the tensile strength and peak toughness of HPHFRCCs even at high strain rates (74 ~ 161 /sec).

This study assesses the adequacy of a critical value of the FEMA 273 for beams utilized in the present performance-based design. From the comparison the critical values of FEMA 273 with those of previous experimental result about beams, it was shown that FEMA 273 underestimated the critical values. Therefore, it is necessary to perform a research to find the hysteresis model for the performance-based design considering the hysteretic behavior of domestic reinforced concrete members.

This paper is to investigate the stress-strain curves for STS 201 austenitic stainless steel over the full strain range. Ramberg-Osgood expression can be used to predict the stress-strain curve up to the 0.2% proof stress. Rasmussen and Shin have developed the approach for stress-strain curve of stainless steels beyond 0.2% proof stress based on the Ramberg-Osgood concept. However, for STS201 stainless steel, two existing concepts were not available for predicting the curves and therefore modified method was discussed in this paper.

To evaluate the compressive characteristics of concrete with high strain rate, SHPB(Split Hopkinson Pressure Bar) test is typically used. To verify the applicability and reliability of SHPB test for concrete, direct displacement image analysis with high speed camera was performed using plain concrete and UHPC.

이 연구는 대학 환경 관련 교양 수강생 41명이 유전자변형농작물(GMO)에 대한 다큐멘터리 시청과 패널토론 후, 지속가능한 농업 측면에서 GMO를 각각 평가하고 비교했다. 그 결과, GMO는 경제적 지속가능성 측면 평가에서는 통계적으로 유의미한 차(p<0.05)가 있었으나, 사회적 지속가능성과 환경적 지속가능성에서는 통계적으로 유의미한 차가 나타나지 않았다. GMO의 경제적 지속가능성에서 다큐멘터리 시청과 패널토론 간 평가 차는 패널토론에서 이공계열(그룹3)과 인문계열(그룹1)/사회계열(그룹2) 간 차에 기인한 것으로, 이는 통계적으로 유의미했다(p<0.01). 다큐멘터리 시청 후 GMO가 경제적 지속가능성이 있다고 평가한 이공계열 학생 중 43%가 패널토론 후에는 경제적 지속가능성이 없다고 평가한 이유는 다음과 같이 나타났다. 첫째, GMO로 식량 생산량은 증가했으나 여전히 식량 부족 문제를 해결하지 못하고 있다. 둘째, 식량 생산 이익이 다국적기업 이익에만 치중되어 있다. 셋째, 농작물 독과점 문제가 생길 수 있기 때문이다. 이는 향후 GMO 기술이 경제·사회·환경과의 유기적인 관계 속에서 지속가능한 농업을 지원하는 방향으로 나아가야 함을 함의한다.

충돌 또는 폭발 하중 하의 콘크리트는 정적 하중에서 가지는 재료물성과 다른 거동을 보이게 된다. 즉, 고변형율 하의 콘크리트의 재료물성은 크게 변화하게 되며, 이를 시험평가하기 위한 방법 중 압축강도와 관련된 시험법으로는 SHPB(Split Hopkinson Pressure Bar) Test가 있다. 그러나, SHPB Test는 금속과 같은 인성재료를 위해 개발된 시험방법으로서 취성재료인 콘크리트에 적용이 가능한지에 대한 검토가 추가적으로 필요하며, UHPC와 같은 섬유보강 초고성능 콘크리트에 대한 연구는 미미한 실정이다. 이에 본 연구에서는 콘크리트 시험체를 위해 제작된 SHPB Test 장비를 사용하여 일반 콘크리트 및 UHPC 시험체에 대한 시험평가를 수행하였으며, SHPB Test의 적용 적정성을 파악하기 위하여 초고속카메라를 활용한 변위영상 분석을 통한 검증을 수행하였다.

In this study, longitudinal strain distribution of spliced rebar in the 1-directional tension test are evaluated with an image processing method (IPM). From these results, it is estimated that the coupler can decrease the elongation at the ultimate load, therefore, the spliced rebar with coupler should be evaluated to be used in the RC structure with LSD.

In this study, longitudinal strain distribution of rebar in the 1-directional tension test are evaluated with an image processing method (IPM). From these results, it is estimated that the necking region can make the over estimation of elongation of rebar, therefore, the estimation except the necking region can be suggested to evaluate the true elongation of rebar.

The purpose of this study was to investigate the strain characteristics of frame retrofitting grid-type seismic member. The experimental investigation consisted of a cyclic load tests of one story-one bay reinforced concrete frame retrofitting grid-type seismic member.

Recent earthquake of incidence is increasing. The purpose of this study was to investigate the strain characteristics of bare frame with non-seismic details. The experimental investigation consisted of a cyclic load tests on 1/3-scale models of one story-one bay bare reinforced concrete frame.

This study investigates the ultimate strength and curling influence in single shear bolted connection with aluminum alloys(6061-T6) using finite element analysis. The applicability of numerical modeling was validated through the comparison of existing test results. Main variables are end distance and edge distance. Strength reduction ratio by curling was estimated quantatively and it is known that the curling reduced the ultimate strength by maximum 26%.

This study evaluated the lateral thermal deformation induced by environmental factors for a precast I-girder. Lateral temperature gradients across the cross-section of the girder were calculated using analytical equations based on daily solar radiation, temperature variation, and wind speed. Then the lateral thermal deformation showed an average of approximately 40% to 71% of the tolerance for the initial lateral deformation of the girder, defined in the PCI bridge design standard.

In this study, Lead Rubber Bearing(LRB) characteristics calculated by the design of the seismic isolation system, according to the seismic isolation structure with the application of nuclear power plants. Experiments were carried out to analyze the compression characteristics of prototype LRB under variable shear displacement.

This research investigated the effects of adding micro fibers on the direct tensile behavior of ultra-high-performance hybrid-fiber-reinforced concrete (UHPHFRC) at high strain rates. Macro fiber was long smooth fiber (LS, Df=0.3mm, Lf=30mm) and micro fiber was short smooth fiber (SS, Df=0.2mm, Lf=13mm). The volume content of macro fibers was 1.0% and the volume content of micro fibers varied between 0.0 and 1.0%. The addition of micro fibers clearly increased the tensile strength of UHPHFRCs even at high strain rates.