본 연구에서는 인디안구스베리(암라), 찔레나무, 쏘팔메토열매를 5:1:1 비율로 Complex하고 추 출하여 0%, 0.5%, 2.5%, 12.5%, 100%의 NF Complex를 제조하였다. 제조한 NF Complex로 탈색한 시 료 모발에 도포 후 손상된 모발과 비교 · 분석하였다. 개선 효과를 확인하기 위해 인장강도, 광택, 흡광도, 명도를 측정하였다. 측정 결과 인장강도는 증가하였다. 광택은 함량이 100%는 감소하고 나머지 함량은 증 가하였다. 흡광도는 손상모와 대조군과의 차이가 있어 개선 효과가 있는 것으로 보인다. 명도는 변화는 있 으나 미미하였다. NF Complex의 평균값은 유의미한 차이가 있음을 확인하였으며 추후 다양한 추출방법 및 혼합 비율에 따른 연구가 필요하다고 판단된다.

In this study, the physical properties and fracture characteristics according to the tensile load are evaluated on the materials of the polymeric filler and carbon fiber-based composite sleeve technique. The polymeric filler and the composite sleeve technique are applied to areas where the pipe body thickness is reduced due to corrosion in large-diameter water pipes. First, the tensile strength of the polymeric filler was 161.48~240.43 kgf/cm2, and the tensile strength of the polyurea polymeric filler was relatively higher than that of the epoxy. However, the tensile strength of the polymeric filler is relatively very low compared to ductile cast iron pipes(4,300 kgf/cm2<) or steel pipes(4,100 kgf/cm2). Second, the tensile strength of glass fiber, which is mainly used in composite sleeves, is 3,887.0 kgf/cm2, and that of carbon fiber is up to 5,922.5 kgf/cm2. The tensile strengths of glass and carbon fiber are higher than ductile cast iron pipe or steel pipe. Third, when reinforcing the hemispherical simulated corrosion shape of the ductile cast iron pipe and the steel pipe with a polymeric filler, there was an effect of increasing the ultimate tensile load by 1.04 to 1.06 times, but the ultimate load was 37.7 to 53.7% compared to the ductile cast iron or steel specimen without corrosion damage. It was found that the effect on the reinforcement of the corrosion damaged part was insignificant. Fourth, the composite sleeve using carbon fiber showed an ultimate load of 1.10(0.61T, 1,821.0 kgf) and 1.02(0.60T, 2,290.7 kgf) times higher than the ductile cast iron pipe(1,657.83 kgf) and steel pipe(2,236.8 kgf), respectively. When using a composite sleeve such as fiber, the corrosion damage part of large-diameter water pipes can be reinforced with same level as the original pipe, and the supply stability can be secured through accident prevention.

인장 강도는 복합 재료를 설계하기 위한 필수 변수이므로 개방 홀 인장 시험을 통해 복합 재료의 인장 강도를 측정한다. 그러나 인장 시험을 올바르게 모델링하는 것은 섬유와 매트릭스 손상, 층간분리 및 섬유와 매트릭스 사이의 손상 같은 다양한 손상을 수반하기 때문에 매우 어려운 과제다. 따라서 섬유와 매트릭스 사이의 면내 파괴 및 층간분리를 평가하기 위해 본 연구에서는 점진적 손상 모델을 개발하였다. 하신 손상 모델과 응집 영역 접근법을 층과 층간분리를 모델링하는데 사용하였다. 현재 모델의 결과를 이전에 발표된 실험 및 수치 결과와 비교하여 검증하였다. 이를 통해 유한요소해석에서 층간분리를 무시하면 인장 강도가 과대평가 된다는 것을 확인할 수 있었다.

In this study, we studied the damage area detection of the composite tension specimens under fatigue loading by using image processing techniques. The aim of this study is to detect the area of the damage region on the basis of original image. Basically we have used Matlab program. This study analyzed a total of six specimens under cyclic loading and the results using a user algorithm and analysis procedures of step 7. The damaged area was well detected except 3,000 cyclic loading. Accuracy of damage area detection is determined to be excellent by 83.3%(5/6). In general, however, in order to automatically detect the damaged area must develop an algorithm for setting the number of multi-threshold automatically. This is to perform the studies in the future.

Since the collapse of historical masonry structures in Europe in the late 1990’s, the interests in understanding the long-term effect of masonry under sustained compressive stresses have increased. That requires combining the significance of time-dependent effects of creep with the effect of damage due to overstress to realize the evolution of cracks and then failure in masonry. Meanwhile, composite analysis of masonry columns was proven effective for realizing ultimate strength capacity of masonry column. In this study, a simplified mechanical model with step-by-step in time analysis was proposed to incorporate the interaction of damage and creep to estimate the maximum stress occurred in masonry. It was examined that the interaction of creep and damage in masonry can accelerate the failure of masonry.

In this paper, the analysis of impact damage behavior of a reinforced concrete structure that undergoes both a shock impulsive loading and an impact loading due to the air blast induced from an explosion is performed. Firstly, a pair of multiple loadings are selected from the scenario that an imaginary explosion accident is assumed. The RC structures strengthened with advanced composite materials (ACM) are considered as a scheme for retrofitting RC wall structures subjected to multiple explosive loadings and then the evaluation of the resistant performance against them is presented in comparison with the result of the evaluation of a RC structure without a retrofit. Also, in order to derive the result of the analysis similar to that of real explosion experiments, which require the vast investment and expense for facilities, the constitutive equation and the equation of state (EOS) which can describe the real impact and shock phenomena accurately are included with them. In addition, the numerical simulations of two concrete structures are achieved using AUTODYN-3D, an explicit analysis program, in order to prove the retrofit performance of a ACM-strengthened RC wall structure.

본 연구에서는 입자강화 복합재료(particle-reinforced composites)의 거동을 예측하기 위하여 Lee and Pyo(2007)에 의해 제안된 계면손상을 고려한 복합재료의 미세역학 탄성모델과 Karihaloo and Fu(1989)의 미세균열 생성모델을 결합하여, 보강입자의 계면손상(imperfect interface)과 기지 내 미세균열을 고려하여 탄성구성모델(constitutive model)의 거동해석을 수행하였다. 제안된 탄성구성모델의 적용성 검증과 주요손상변수가 거동예측에 미치는 영향을 알아보기 위해 일축 하중 하에서의 응력-변형률 관계를 수치적으로 나타내었다. 또한, 기존의 관련 실험결과와 본 해석결과와의 비교를 통하여 제안된 모델의 정확도를 검증하였다.

The purposes of this study were to test that complex motor training enhance motor function significantly, to test change in cerebellum, and to test the synaptic plasticity into the immunohistochemistry response of synaptophysin. Using an animal model of fetal alcohol syndrome - which equates peak blood alcohol concentrations across developmental period - the effects of alcohol on body weight during periods were examined. The effect of complex motor training on motor function and synaptic plasticity of rat exposed alcohol on postnatal days 4 through 10 were studied. Newborn rats were assigned to one of two groups: (1) normal group (NG), via artificial rearing to milk formula and (2) alcohol groups (AG), via 4.5 g/kg/day of ethanol in a milk solution. After completion of the treatments, the pups were fostered back to lactating dams, where they were raised in standard cages (two-and three animals per cage) until they were postnatal 48 days. Rats from alcohol group of postnatal treatment then spent 10 days in one of two groups: Alcohol-experimental group was had got complex motor training (learning traverse a set of 6 elevated obstacles) for 4 weeks. The alcohol-control group was not trained. Before consider replacing with "the experiment/study", (avoid using "got" in writing) the rats were examined during four behavioral tests and their body weights were measured, then their coronal sections were processed in rabbit polyclonal antibody synaptophysin. The synaptophysin expression in the cerebellar cortex was investigated using a light microscope. The results of this study were as follows: 1. The alcohol groups contained significantly higher alcohol concentrations than the normal group. 2. The alcohol groups had significantly lower body weights than the normal group. 3. In alcohol groups performed significantly lower than the normal group on the motor behavioral test. 4. In alcohol-control group showed significantly decreased immunohistochemistric response of the synaptophysin in the cerebellar cortex compared to the nomal group. These results suggest that improved motor function induced by complex motor training after postnatal exposure is associated with dynamically altered expression of synaptophysin in cerebellar cortex and that is related with synaptic plasticity. Also, these data can potentially serve as a model for therapeutic intervention.

본 증례연구는 복합손상을 가진 척수손상환자의 재활치료과정을 소개하여 유사한 사례의 치료에 도움이 되고자 하는 것이다. 증례연구의 대상자인 26세의 남자환자는 흉수 4번 완전손상과 사고 당시 전기화상에 의한 좌측하박 절단과 우측손의 정중신경이 마비되었다. 치료초기에는 일상생활동작 검사에서 MBI (Modified Barthel Index) 점수가 22점으로 독립적으로 가능한 것은 거의 없었고, 기능적으로도 모든 도움이 필요한 상태였으나 재활치료결과 독립적

The marine structures with sea water cooling system always expose to the oceanic atmosphere. Therefore, the protection of the equipments is very important. To investigate the effectiveness of advanced composite materials for the application in offshore environments, the tensile test, hardness test, undercutting property test, permeance test and the friction and wear test were carried out by using various applicable coating materials. The main results obtained can be summarized as follows; 1. The micro-hardness of the Archcoat 502B showed the highest value. 2. The coefficient of friction of the Rigspray coating at the speed of 2.21m/sec showed the lowest value, and that of the Archcoat 502B coating at 1.08m/sec and 0.18m/sec indicated the lowest values. 3. The wear mass at the speed of 0.18m/sec and 1.08m/sec in dry condition showed the smallest values. 4. The Archcoat 502B coating is fitted to the dynamic instruments in the range of low speed and middle speed. Rigspray coating is fitted to the dynamic instruments in the range of high speed. 5. The wear mass of five kinds of coating materials at the range of low speed was very small, and those of the Archcoat S02B, Archcoat 402B and Rigspray coating at high speed range were quitely smaller than those of the Modified Epoxy and Tar Epoxy.

본 연구는 적충복합보에 있어서의 층간분리현상을 추적하는 기법을 소개하고 있다. 이 기볍에서는 충간분 리된 보와 층간분리되지 않은 보와의 응답차이를 최대화하도록 조화운동의 가력올 보위별로 최적화한다.2개 층의 알루미늄 보에 대하여 수치해석을 수행하였으며， 계측 및 보의 형태에 따른 노이즈를 고려하였다. 층간 분리를 모텔링하기 위하여 스웹함수를 사용하였으며 층별복합판 이론에 기본한 유한요소법을 이용하여 해석 하였다.

In this paper, the effect of steel fiber-reinforced cement composite (SFRCC) on damage resistance of steel tube member. Test results show that the cumulative energy dissipation of SFRCC specimen was about 14% higher than that of Con specimen.

The effect of steel fiber types on the self-sensing capacity of strain-hardening fiber-reinforced cementitious composites (SH-SFRCs) was investigated. Three types of fiber, including twisted, smooth and hooked fibers, were used with a volume content of 1.5% in a mortar matrix. Although all the SH-SFRCs exhibited self damage-sensing capacity, the gauge factor, representing for damage-sensing ability, was different according to the types of fiber as follows: twisted (138.09) > smooth (99.85) > hooked (88.50). The SH-SFRC with twisted fiber produced the highest gauge factor which is very favorable for development of self damage-sensor.

복합소재는 가벼운 중량과 높은 비강성 및 비강도의 장점을 갖는다. 본 연구에서는 고성능 방재를 위하여 층간 분리 손상을 갖는 복합소재 구조에 대한 유한 요소 모델링을 엄밀한 고차항 판 이론에 근간하여 수행하였다. 3차원의 층간분리 현상을 절점당 7개의 자유도를 갖는 2차원 유한요소로 정식화하여 층간분리영역 경계에서의 변위를 일치시키기 위한 변환기법을 적용하였다. 유한요소 정식화 과정에서, 본 연구에서는 다음과 같은 영역에서의 세가지 타입의 요소를 적용하였다. (1) 층간분리가 일어나지 않은 영역 (2) 층간분리가 일어난 영역에서의 요소 (3) 층간분리가 시작되는 경계 영역에서의 요소. 층간분리 영역은 동일한 위치에서 층간분리의 윗부분 요소와 아랫 부분 요소로 구분하여 적용하였다.

최근 사회 기반 시설물에서 구조물의 안전성 및 적정 성능 수준을 확보하기 위하여 구조물의 결함 빛 노후화에 의한 성능 저하 등을 상시적으로 모니터링하기 위한 관심이 높아지고 있다. 이 중 배관 구조물은 국가 주요 자원의 수송을 책임지는 핵심 사회 기반 시설물임에도 불구하고 지중에 매립된다는 위치적 특성 상 상시적으로 구조물의 상태를 모니터링하기는 매우 어렵다. 또한 배관 구조물에서는 내부 미세 균열에서부터 국부 좌굴, 볼트 풀림, 피로 균열 등과 같이 다양한 형태의 손상이 복합적으로 발생 가능하다. 따라서 본 연구에서는 이러한 복합 손상을 효율적으로 진단하기 위하여 압전센서를 이용한 자가 계측 회로 기반의 유도 초음파 계측 시스템을 복합 손상 진단에 적용하였다. 유도 초음파 자가 계측으로부터 특정 중심 주파수에 해당하는 구조물의 웨이블렛 응답을 계측한다. 복합 손상을 유형별로 분류하기 위하여 유도 초음파 계측으로부터 추출한 특성을 이용하여 손상지수를 계산하고 이를 지도학습 기반 패턴인식 기법에 적용한다. 제안된 기법의 적용성 검토를 위하여 배관 구조물에 인위적으로 다중 손상을 생성시켜 시험을 수행하였다.