본 논문에서는 변형에 의해 유발된 패턴변화(pattern transformation)에 기반하여 압축(compression)과 인장(tension) 하중 모두에서 음의 포아송 비(negative poisson’s ratio)를 나타내는 다공성(porous) 구조를 제안한다. 기존에 개발된 원형 구멍을 이용한 구조는 연결선(ligament)의 회전 모멘트 부족으로 인해 인장 시 양의 포아송 비를 나타내는 한계점이 있었으며, 타원 형 구멍을 이용한 구조는 응력집중 현상으로 인하여 내구성(durability)이 약한 문제점이 있었다. 이에 본 연구에서는 휘어진 연결선의 배열을 통하여 인장하중 하에서의 회전 모멘트를 증가시키는 동시에 응력집중 현상을 완화하고 변형에너지(strain energy)를 구조물 전반에서 고르게 흡수하도록 설계하였다. 이를 통해 10%의 공칭 변형률(nominal strain) 범위 내의 압축 과 인장 모두에서 음의 포아송 비를 가지며, 기존 모델에 비하여 강성(stiffness)과 내구성이 개선된 구조를 개발하였다. 비선 형 유한요소해석을 통하여 기존 타원형 구멍 모델과의 비교를 수행하였으며 제안된 모델이 구조의 강성과 내구성 측면에서 현저히 개선됨을 확인하였다.

In the seismic design of building structural members, due to the complexity of the placement of PC steels in prestressed concrete members, it is necessary to review and define the definition of member damage in comparison with reinforced concrete members.In this study, the results of past experiments compared with the calculation results by ‘section Analysis Method’, with the aim of reviewing the precision of calculation results when member damage evaluation is performed using the section analysis method. Furthermore, it is also compared with the calculation results by the ‘split Element Method’.In addition, parametric studies were carried out, and the influence of the difference between the amount of PC steels and reinforced bar on the residual strain was examined.

The purpose of this study is to make a generalized analytical based on the proposed experiments on reinforced concrete(RC) partially infilled frames by U-type precast concrete(PC) wall panels with openings. RC frame and PC wall panels were connected with different strengths. Therefore, we developed modified strut-tie model(STM) with two seismic retrofitting specimens and conducted a nonlinear analysis by using a computer analysis program. Based on the test results, truss member of modified STM was designed, applying the strut-tie model theory of ACI 318M-11 Appendix- A. As a result, the modified STM analysis results were very similar to the experimental results. As a result of the load-displacement curve comparison, the failure load were similar within 5∼17% of error range. In particular, the experimental results and the results of modified STM analysis show that the failure behavior almost matched.

Cyclic loading test was performed on the partially infilled reinforced concrete(RC) frames by L-type precast concrete(PC) wall panels with the connections of two different strength. Based on the results of experimental test, the nonlinear analysis was practiced with modified strut-tie model(STM) method by using a computer program. Truss member of modified STM was designed, applying the strut-tie model theory of ACI 318M-11 Appendix-A. Modified STM was designed with two ways according to the test result. PC wall panel and RC frame were assumed to composite when push loading applied. The PC and RC structures were also assumed to behave non-composite and those two structures connected with link(top connector) when pull loading applied. The connection was designed by using elastic link of program. The results of analytical modified STM process generally conform to the experimental results. The failure load and the failure mode of the specimens could be predicted using modified STM. The ratio of failure load measured in specimens to analytical values were between 0.83∼1.16. The member or connection which was failed in experiment yield in the results of modified STM. The failure mode perfectly matched.

The global small and mid-sized display market is changing from thin film transistor-liquid crystal display to organic light emitting diode (OLED). Reflecting these market conditions, the domestic and overseas display panel industry is making great effort to innovate OLED technology and incease productivity. However, current OLED production technology has not been able to satisfy the quality requirement levels by customers, as the market demand for OLED is becoming more and more diversified. In addition, as OLED panel production technology levels to satisfy customers’ requirement become higher, product quality problems are persistently generated in OLED deposition process. These problems not only decrease the production yield but also cause a second problem of deteriorating productivity. Based on these observations, in this study, we suggest TRIZ-based improvement of defects caused by glass pixel position deformation, which is one of quality deterioration problems in small and medium OLED deposition process. Specifically, we derive various factors affecting the glass pixel position shift by using cause and effect diagram and identify radical reasons by using XY-matrix. As a result, it is confirmed that glass heat distortion due to the high temperature of the OLED deposition process is the most influential factor in the glass pixel position shift. In order to solve the identified factors, we analyzed the cause and mechanism of glass thermal deformation. We suggest an efficient method to minimize glass thermal deformation by applying the improvement plan of facilities using contradiction matrix in TRIZ. We show that the suggested method can decrease the glass temperature change by about 23% through an experiment.

PURPOSES: This study is primarily focused on evaluating the effects of the non-linear stress-strain behavior of RAP concrete on structural response characteristics as is applicable to concrete pavement. METHODS : A 3D FE model was developed by incorporating the actual stress-strain behavior of RAP concrete obtained via flexural strength testing as a material property model to evaluate the effects of the non-linear stress-strain behavior to failure on the maximum stresses in the concrete slab and potential performance prediction results. In addition, a typical linear elastic model was employed to analyze the structural responses for comparison purposes. The analytical results from the FE model incorporating the actual stress-strain behavior of RAP concrete were compared to the corresponding results from the linear elastic FE model. RESULTS : The results indicate that the linear elastic model tends to yield higher predicted maximum stresses in the concrete as compared to those obtained via the actual stress-strain model. Consequently, these higher predicted stresses lead to a difference in potential performance of the concrete pavement containing RAP. CONCLUSIONS : Analysis of the concrete pavement containing RAP demonstrated that an appropriate analytical model using the actual stress-strain characteristics should be employed to calculate the structural responses of RAP concrete pavement instead of simply assuming the concrete to be a linear elastic material.

This paper is concerned with a test method that can be used to investigate the parameters of the Johnson-Cook constitutive model. These parameters are essential for accurately analyzing material behavior under impact loading conditions in numerical simulation. Ti-6Al-4V alloy (HCP crytal structure) was used as a specimen for the experiments. In the 10−3-103/ s strain rate range, three types of experimental methods (convention, compression and tension) were employed to compare the differences using MTS-810, SHPB and SHTB. Finite element analysis results when applying these parameters were displayed along with the experiment results.

Due to a lack of the hoop action of lateral reinforcements the effective confining force in rectangular sections reduces compared to circular ones. Therefore, the stress-strain model obtained from the experimental data with circular sections overestimates the lateral confinement effect in rectangular sections, which evaluates seismic safety margin of overall structural system excessively. In this study experiments with laterally-confined square sections have been performed and the characteristic values composing stress-strain model have been analyzed. With introduction of section coefficients, in addition, the new unified stress-strain model applicable to square sections as well as circular ones has been proposed.

In order to avoid collapse of bridges in earthquakes bridge piers are generally designed to attain sufficient ductility. This full-ductility design method has merits for securing the seismic safety readily against strong earthquakes but, it has weakness of high cost design because of excessive safety margin. Recently, in many countries with high seismic technologies, the seismic design concept tends to shift from the collapse prevention design to the performance-based one which requires different performance (damage) levels according to the structural importance. In order to establish this performance-based design method the displacement ductility of confined concrete members should be evaluated quantitatively. And the stress-strain model of confined concrete is indispensible in evaluating displacement ductility. In this study, 6 test groups with different lateral reinforcement ratios were prepared. 10 same specimens with circular section for each group were tested to obtain more reliable test results. The characteristic values necessary for composing the stress-strain model were obtained from experiments. Based on these characteristic values the new stress-strain model modifying the Hoshikuma's one has been proposed.

Photo responsive polymer(PRP) is well known for its photo deformation under UV light, and goes back to its original shape in visible light due to the photoisomerization of the azobenzene inside the PRP. In this paper, dynamic study of the vibration in PRP is discussed. In order to predict photo-deformation of the PRP a multiscale modeling is introduced which covers quantum level photo excitation, microscopic morphology, and macroscopic deformation of the PRP. A simple 1D beam model is introduced to model dynamic bending behavior of the PRP. Through fast Fourious transformation analysis, we identify that vibration frequency of the PRP can be controlled by light polarization angle.

우리는 누구나 삶 속에서 여러 가지 갈등과 고난을 경험하게 된다. 이러한 문제를 해결하기 위해서, 근본적인 치료는 개인으로 하여금 영적으로 각성시키고, 개인의식의 핵심인 욕망을 알아차리게 하고, 우주의식을 갖도록 했을 때, 비로소 근본적인 치료가 일어난다. 결론적으로 마음을 완전히 치료한다는 의미는 의식의 성장 과 변형을 의미한다. 아유르베다는 아슈땅가요가의 8지칙에 따라 체질별 수행 방법이 있다. 그리고 이러한 8 지칙의 수행을 따라 가다보면 저절로 의식의 변형이 일어난다. 그러므로 의식변형 없이는 완전한 치료는 어렵 다는 것을 알 수 있으며, 홀리스틱 치료를 위해서도 요가 수행이 필요하다는 결론이다. 본 연구는 요가 수행 을 뒷받침하는 것이 아유르베다의 치료 기법들이며 수행기법들이라는 점을 알리고자 했으며, 또한 의식변형을 이끄는 단계를 요가와 아유르베다를 통해서 알아보고자 했다.

본 연구는 경상남도 하동군 옥종면 땅밀림 산사태지의 붕괴지 및 피해지역을 중심으로 사면붕괴양상을 규명하기 위해 땅밀림 산사태지의 인장균열지의 월별 변화양상을 조사하였다. 그 결과, 연구대상지에서는 땅밀림 산사태 발생징후라 판단되는 지하수 용출, 융기 및 함몰, 수목이상성장 등이 발견되었다. 아울러 당초 인장균열 두께와 폭은 1 : 4.2, 폭과 길이는 1 : 1.5로 나타났으며, 월평균 인장균열의 증감 폭은 폭 > 길이 > 상단부 사면길이 > 단차 순으로 나타났다. 한편, 강우인자와 인장균열의 형태 및 인장균열의 형태 중 세부인자들 간의 상관분석을 실시한 결과, 모두 상관관계가 없는 것으로 나타났다.

The present study deals with the effects of micro-alloying elements such as Ni, V, and Ti on the recrystallization behavior of carbon steels at different strain rates. Eight steel specimens were fabricated by varying the chemical composition and reheating temperature; then, a high-temperature compressive deformation test was conducted in order to investigate the relationship of the microstructure and the recrystallization behavior. The specimens containing micro-alloying elements had smaller prior austenite grain sizes than those of the other specimens, presumably due to the pinning effect of the formation of carbonitrides and AlN precipitates at the austenite grain boundaries. The high-temperature compressive deformation test results indicate that dynamic recrystallization behavior was suppressed in the specimens with micro-alloying elements, particularly at increased strain rate, because of the pinning effect of precipitates, grain boundary dragging and lattice misfit effects of solute atoms, although the strength increased with increasing strain rate.

형질전환(Living Genetically Modified)벼와 비변형 벼 재배지역의 곤충상 변동 양상을 2016년 7월부터 2016년 10월까지 비교 조사중이다. 경상대 사천 LMO 격리포장과 경북대 군위 LMO 격리포장에서 Bt(Bacillus thuringiensis) 형질전환 벼를 재배하여 조사하였고, 사천시 두량리, 선진리, 군위군 화계리에서 비변형 벼 재배지를 선택하여 조사하였다. 현재까지 조사결과로 사천 LMO 격리포장에서는 총 10목 41과 86종 1,058개체, 군위 LMO 격리 포장은 총 11목 49과 103종 1,697개체, 두량1 포장은 총 9목 38과 80종 1,035개체, 두량2 포장은 총 11목 55과 101종 1,071개체, 선진 포장은 총 10목 43과 74종 428개체, 화계1 포장은 총 10목 44과 83종 2,663개체, 화계2 포장은 총 11목 51과 98종 1,556개체가 채집되었다. 현재 형질전환 벼와 재배 벼 사이의 차이가 나타나지 않았다. 10월까지 실험을 진행, 군집분석하여 비교할 예정이다.

감자는 세계에서 4번째로 중요한 식량작물로 식품 및 사료로 이용되고 있다. 감자의 주요 소비형태는 일반식용 위주와 전분, 감자칩, 감자튀김 등 다양한 형태의 가공제품, 씨감자 형태로 사용한다. 또한 감자를 식품산업과 제지 산업에서 활용하기 위해 amylose 함량을 감소시키거나 acrylamide 생성을 줄인 유전자변형 감자가 개발되고 있다. 이 에 따라 우리나라의 경우 감자 가공품 수입이 많은 만큼 국내외 감자 제품에 대한 미승인 유전자변형 감자에 대한 검사법이 필요하다. International Service for the Acquisition of Agri-biotech Applications (ISAAA) 보고에 따르면 2016 년까지 45개의 GM 감자이벤트가 개발되었다. 이 중 우리나라는 식품의약품안전처로부터 4종의 GM 감자가 식품용 도로 승인되었다. 본 연구에서는 현재 미승인 유전자 감자 6개 이벤트에 대해 정성검사용 표준플라스미드 (pUC_GM potato A and B)를 제작하였으며, UDP-glucose pyrophosphorylase (UGPase) gene을 감자 내재유전자로 사용했다. 개발 된 표준플라스미드는 식품의약품안저처의 고시를 토대로 primers와 probes를 이용하여 Applied Biosystems ViiA7 real-time PCR system을 통해 정성분석을 수행하였다. 또한 검정한계치를 확인하기 위해 플라스미드를 100,000 - 10 copies까지 희석한 것을 주형으로 하여 real-time PCR을 진행하였다. 이와 같이 미승인 유전자변형 감자에 대한 정성 분석용 표준플라스미드가 개발되었으며 국내 미승인 유전자변형 감자에 대한 모니터링에 활용될 수 있을 것으로 기 대한다.

본 연구에서는 신규 승인 및 승인 예정인 유전자변형 콩 5개 이벤트(SYHT0H2, DAS-44406-6, MON87751, DAS-81419-2, DAS-68416-4)의 정량분석에 사용할 시험대조물질로써 플라스미드(pUC-GM soy C, D)를 개발하였다. 각각의 표준플라스미드는 콩 내재유전자인 lectin의 증폭서열을 포함하고 있으며, pUC-GM soy C에는 4개의 이벤트가, pUC-GM soy D에는 하나의 이벤트가 포함되었다. Applied Biosystems의 Viia7 real-time PCR을 통해 개발된 표준플라 스미드에 대한 검증실험을 실시하였다. 정량분석에 사용된 프라이머, 프로브는 식품공전에 고시되어 있는 것을 사용 하였다. 정량분석을 위한 표준곡선은 20, 200, 2000, 20000, 200000 copies로 희석한 표준플라스미드를 이용하였으며, R2는 0.993-1.000, 표준편차(standard deviation, SD)는 0.01-0.18로 확인되었다. 이와 같이 개발된 표준플라스미드 (pUC-GM soy C, D)가 5개 유전자변형 콩의 정량검사에 calibrator로 사용될 수 있음을 확인하였다.

Magnetostrictive actuator is fabricated with powder nano bonding method instead of sputtering method. Fabrication process and experimental measurement method for magneto-mechanical characteristics is proposed. For the design of highly flexible magnetostrictive actuator, TbDyFe nano powder bonding with Teflon substrate is adopted. The fabrication process for Teflon substrate and nano powder bonding is suggested and magnetostrictive behaviors are investigated. Variable magnetic field is applied to measure the magnetostrictive characteristics and magnetostriction is measured with different waves and different magnitude of magnetic field.