• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.169-179
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• 1997

서론 : Laminin의 수용기로 알려진 Integrin $\alpha6\beta4$의 세포내 표현 정도는 편평상피암을 위시한 여러 악성종양의 전이능력 및 예후와 밀접한 상관관계가 없다고 알려져 있다. 이 Integrin은 Laminin과 같은 세포와 리간드와 결합하면 상피세포의 기저막 지주 구조물인 hemidesmosome의 세포체질 요소(cytoskeletal element)와 연관되어 그 결과 세포의 기저막과 세포내 케라틴을 연결하는 역할을 한다. Integrin $\alpha6\beta4$는 구조적으로 다른 많은 integrin들과 달리 $\beta$4의 세포질내 영역(cytoplasmic domain)이 특징적으로 크다. 이 세포질내 영역 $\beta$4 integrin의 기능은 아직 밝혀지지 않고 있으나 아마 세포 성장의 신호전달 및 악성종양의 특징인 침윤 전이에 관련할 것으로 보아지고 있다. 재료 및 방법: 저자들은 우선 $\beta$4 integrin의 wild type s-DNA와 $\beta$4 세포질내 영역(cytoplasmic domain) 및 $\beta$4의 tyrosine 인산화 반응 부위가 각각 결손된 c-DNA를 PCR을 통하여 합성하여 pRc/CMV 벡터에 삽입한 후 원래 $\beta$4 integrin의 발현이 결집된 인간 방광암 세포에 Calcium phosphate precipitation 방법으로 주입(transfection)시켜 형질변환된 세포를 면역형광법, Flow cytometry 및 Immunoprecipitation 방법으로 클로닝하여 wild type $\beta$4-full length(Clone FL), truncated $\beta$4-cytoplasmic domain(C1one CD), 및 mutated $\beta$4-tyrosine phosphorylation site (Clone M)을 얻었다. 암 세포의 부착 및 침투 능력의 기능적 연구로 모노 클로날 항체와 fibronectin, laminin, Matrigel을 단백질 기질로 사용하였으며 결과 비교를 위하여 pRc/CMV 벡터만 주입시켰던 클로운과 방광암 세포주를 $\beta$4 integrin 음성 대조군으로 또한 이 Integrin의 높은 발현을 보이는 두경부 편평상피암 세포주를 양성 대조군으로 이용하였다. 결과 : 세포부착능력에 있어서 온전한 $\beta$4 cytoplasmic domain이 존재하는 클로운이 laminin에 강한 부착능력을 보였으나 fibronectin의 부착정도는 $\beta$4 integrin의 표현정도와 관계없이 모든 클로운에서 비슷하였다. Matrigel을 투과하는 암세포 침윤 능력에서는 $\beta$4 integrin의 표현이 존재하는 클로운들이 투과 능력이 높았으나 세포외 리간드가 없는 control membrane을 사용하였을 때와 비교하여 투과능력의 차이를 보이지 않았다. 결론 : 유전자 주입(transfection) 방법으로 integrin의 다양한 클로운의 합성이 가능하여 이 Integrin의 암 세포의 부착 및 침투 능력에서의 기능을 규명 할 수 있게 한다. $\beta$4 integrin은 편평상피 암세포의 부착에 있어서 세포외 리간드 laminin과 특이 결합하여 부착 능력을 높이는 중요한 역할을 하며 편평상피 암세포의 침투에 있어서는 $\beta$4 integrin의 표현이 침투 능력을 높이는 역할을 하나 이때에는 laminin과 같은 리간드와의 특이 결합에 의존하지는 않는 것으로 사료된다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.100-107
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• 2018

The objective of this study is to assess the strengthening effects of fiber reinforced polymer(FRP) sheets such as Carbon fiber, Glass fiber, and PET(polyethylene terephthalate) on reinforced concrete flexural members. Variables of theoretical analysis are types of strengthening materials, material properties and amount of strengthening materials. A virtual flexural member without FRP sheets was created as a control specimen to understand the structural behavior of the non-strengthened specimen in terms of elastic and ultimate cross section. In total, 11 specimens including one non-strengthened and ten strengthened specimens were investigated. Various variables such as types of strengthening, strengthening properties, and amount of strengthening were studied to compare the behavior of the control specimen with those of strengthened specimens with regard to moment-curvature relationship. Results of theoretical analysis showed that the moment capacity of strengthened specimens was superior to that of the control specimen. However, the control specimen indicated the best ductility among all the specimens. As the amount of strengthening increased, flexural performance was improved. Furthermore, the results indicated that the ductile effect of members was affected by the ultimate strain of FRP sheets. The strengthening effect on the damaged member was similar to that on the non-damaged one since there was less than 10% difference in terms of flexural strength and ductility. Therefore, even if a damaged member is treated as non-damaged for analysis there is probably no noticeable difference.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.243-253
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• 2011

This paper describes an analytical study on seismic performance of domestic reinforced concrete (RC) school building not designed by seismic provision. The seismic index and the seismic performance of the building were evaluated through Japanese standard and Midas Gen, respectively. Seismic index (Is) of the RC school buildings in the X-direction is below 0.4. Based on the seismic index, for seismic-strengthening the building, infill shear wall or steel brace with a capacity of 1,300 kN was used. According to nonlinear static analysis results, the contribution of the seismic-strengthening to the shear resistance of the school building was measured to be greater than 30%. However, as expected, shear strength of school building strengthened with infill wall dropt rapidly after peak load and much narrower ductile behavior range was observed compared to steel brace strengthened building. Also, the building strengthened with steel brace showed 30% larger spectral displacement than that strengthened with infill shear wall. In nonlinear dynamic analysis, for the time history analysis, the maximum displacement showed tendency to decrease as amount of reinforcement increased, regardless of strengthening method. It was recommended that variable soil properties and earthquake record should be considered for improving seismic performance of buildings in seismic zone.

• The Journal of the Korea Contents Association
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• v.15 no.1
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• pp.366-378
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• 2015

The purpose of this study conducted in the United States was to identify the level of role stressors among professions at centers for independent living and to investigate the relationship between role stressors and burnout at the target population. A total of 218 professions completed a web-based and hard copy survey. The participants reported a mean (standard deviation) score of 22.48 (5.80) for the role conflict dimension, 22.20 (4.30) for the role ambiguity dimension, and 9.14 (2.55) for the role overload. Demographic assessment of the differences on the mean score of the three role stressors revealed significant associations with that age, job title, highest level of education, years of human service experience and working hours per week for role conflict/role ambiguity, and experience in human service for role overload. The role conflict, ambiguity, and overload stressors were significant predictors of emotional exhaustion and depersonalization explaining 26% and 14% of the variance, respectively. None of the stressors significant predicted personal accomplishment. The results indicate that role conflict, ambiguity, and overload are important predictors of burnout among professions at centers for independent living.

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.52-61
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• 2019

On 30 June, 2017, the Ministry of Land, Infrastructure, and Transport announced the minimum size of parking section will be expanded in parking lots. The expansion of parking section could lead to increase in apartment prices because of increase in total area of the parking lots. It is necessary to adjust the column spacing and number in the parking lots and to apply the 8-Bay long-span parking module with good parking efficiency. According to the study, the construction cost of the 6-Bay module and 8-Bay module was almost the same. But The 8-Bay module was more economical than the 6-Bay module because of the reduction in total area of 8-Bay multi-moduel. The Result of construction cost of 8-Bay modules, Removal Deck-plate RC system was most economical. While the construction cost of PC system was higher due to increase in volume of the member, it would ensure sufficient economy by reducing the girder height to apply a pre-stress method. Also, the construction cost of hollow slab system was the highest. But it could be used as the underground parking lots for apartment, because it had the lowest cost per square meter. This Study has a academic significance by proving the applicability of the 8-Bay Module to underground parking lot of apartment. And it is expected that this study will be used as basic data to derive optimal construction method that applies 8-Bay Module.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.119-126
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• 2019

In case of RC(Reinforced Concrete) structures which are constructed in coastal areas, chloride ions in sea water corrode the steel rebar in concrete. Especially in coastal areas, RC structures are affected by not only immersion of sea water, but also tidal of sea water and airborne chloride ions. In this study, marine environment exposure tests are conducted, considering 3 types of exposure environments(immersion zone, tidal zone, splash zone) and the exposure periods of 180 days, 365 days, and 730 days. Also, the concrete mixtures for this study are established, considering 3 levels of W/B(Water to Binder) ratio(0.37, 0.42, 0.47) and 2 levels of substitution rate of Fly ash(0 %, 30 %). In all exposure environments, Fly ash concrete has lower apparent chloride diffusion coefficients than OPC concrete. It is thought that fly ash's pozzolan reaction improves chloride resistance of concrete. Fly ash concrete has up to 63.5 % of decreasing rate in 180 days of exposure and up to 55.8 % of decreasing rate in 730 days of exposure, based on diffusion coefficients of OPC concrete. As a result of evaluation about effects of exposure environments, apparent chloride diffusion coefficients of fly ash concrete are evaluated in order of tidal zone, immersion zone, and splash zone. In tidal zone, It is thought that repeated cycles of wetting and drying of sea water cause the diffusion of chloride ions rapidly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.82-92
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• 2019

The purpose of this study was to analyze the relationship and degree of agreement between the six types of Geometry Psychological Assessment (GEOPIA) and four functions of the Myers-Briggs Type Indicator (MBTI) personality test, and to investigate the appropriate level of vocational aptitude commonly recommended by each tool. A total of 377 adult men and women from Korea, aged between 19 and 70 years, were tested using GEOPIA and the MBTI. Cronbach's alpha was calculated to verify the validity and reliability of the measuring tools, and the mean and standard deviation of each variable were calculated. Also, a cross-sectional analysis was conducted to examine the relationship between GEOPIA and the MBTI. The results showed that Round/Triangle (RT) types, Round/Box (RB) types, Triangle/Box (TB) types and Box/Curve (BC) types among the GEOPIA personality types are highly related to MBTI's Sensing/Thinking (ST) types. GEOPIA RC types were related to Intuition/Feeling (NF) and Sensing/Feeling (SF) types, and TC types were highly related to Intuition/Thinking (NT) types. Based on the common characteristics of the two tests, the findings suggest appropriate levels of vocational aptitude. Through this research, it was confirmed that GEOPIA (a Korean psychology and personality test) can be used in counseling, coaching, and education, and above all, is a reliable tool for vocational psychological assessment to search for career aptitude.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.61-72
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• 2018

In this study, applicability of the decentralized water supply system were investigated by the high flux evaluation using ceramic membrane with combined pretreatment process. A) filtration process increased the transmembrane pressure of 1.4 kPa and 89.5 kPa on 2 and $5m^3/m^2{\cdot}d$ of filtration flux, respectively, the physical backwashing recovery rate were less than 28.6%. The (B) Coag./Floc. - Sedi. combined process with 4 mg / L of A-PAC showed that the transmembrane pressure increased to within 6 kPa, the physical backwashing recovery rate was over 37.9 % higher than (A) Filtration process. (C) Coag./Floc. combined process showed an increase of transmembrane pressure compared with (B) Coag./Floc. - Sedi. combined process, physical backwashing recovery rate was over 84%. As a result of the membrane fouling analysis using the resistance in series model, the combined pretreatment process showed that the cake resistance (Rc) was more than 92% at membrane filtration flux of $2m^3/m^2{\cdot}d$. In the (C) Coag./Floc. combined process, cake resistance(Rc) was over 86% on high flux conditions. The coagulation floc contained in influent was removed by the membrane, and the cake layer formed with the removed floc was identified as reversible fouling resistance which could be recovered by physical backwashing. The decentralized water supply system, which has the limitation of site area and installation space, is considered to could be operation of high flux of ceramic membrane by applying (C) Coag./Floc. combined process without sedimentation process.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.40-47
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• 2021

In this study, the structural behavior by the details of the lap region with the headed bar was estimated through finite element analysis. To solve the finite element analysis of the anchorage region with complex contact conditions and nonlinear behavior, a quasi-static analysis technique by explicit dynamic analysis was performed. The accuracy of the finite element model was verified by comparing the experimental results with the finite element analysis results. It was confirmed that the quasi-static analysis technique well reflected the behavior of enlarged headed bar connection. As a result of performing numerical analysis using 21 finite element models with various development lengths and transverse reinforcement indexes, it was confirmed that the increase of development length and transverse reinforcement index improved the maximum strength and ductility. However, to satisfy the structural performance, it should be confirmed that both design variables(development length and transverse reinforcement index) must be enough at the design criteria. In the recently revised design standard(KDS 14 20 52 :2021), a design formula of headed bar that considers both the development length and the transverse reinforcing bar index is presented. Also the results of this study confirmed that not only the development length but also transverse reinforcing bars have a very important effect.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.6
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• pp.64-72
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• 2022

In this study, in order to confirm the seismic performance of reinforced concrete frames retrofitted with Wall Friction Damper(WFD), the test was conducted by setting two-story Reinforced concrete frames (reference specimen, OMF-N and specimen retrofitted with internal H-shaped steel frame and WFD, OMF-ALL(H)) as main variables. The WFD Seismic Retrofit Method is a mixture of strength improvement and energy dissipation methods. To prevent the pre-destruction of existing structure by friction force before sufficient energy dissipation of WFD, the internal H-shaped steel frame and chemical anchor that penetrates the side of the beam were used to install WFD. According to the test results, the OMF-N specimen showed an brittle failure pattern caused by the shear force of the R/C column after the maximum strength was expressed. The OMF-ALL(H) specimen showed that the reduction of pinching effect and the failure of the RC column occurred. Also, the maximum strength, cumulative energy dissipation and ductility of OMF-ALL(H) increased 3.01 times, 7.2 times and 1.72 times for OMF-N. As a results, test results revealed that the WFD Seismic Retrofit Method installed on Reinforced concrete structure improves the seismic performance and the strengthening effect is valid.