본 연구는 간호보건계열 대학생의 전공만족도, 진로성숙도가 취업스트레스에 미치는 영향을 알아보기 위한 서술적 조사연구이다. 본 연구는 G시의 3개학과 간호보건계열 대학생 410명을 대상으로 2017년 9월 26일부터 10월 31일까지 설문조사하였다. 수집된 자료를 토대로 기술통계, ANOVA, ANCOVA, Pearson correlation coefficients, Multiple regression으로 분석하였다. 연구결과, 전공선택 동기에 따라 전공만족도(F=9.856, p<.001) 및 진로성숙도(F=6.005, p=.001)가 유의한 차이가 있었으며, 학점은 진로성숙도(F=2.755, p=.042) 및 취업스트레스(F=3.503, p=.016)와 유의한 차이가 있었다. 또한 토익점수는 전공만족도(F=4.514, p=.004)와 유의한 차이가 있었다. 취업스트레스는 전공만족도(r=-.314, p<.001)와 진로성숙도(r=-.514, p<.001) 간에 유의한 상관관계가 있었으며 취업스트레스에 영향을 미치는 요인으로는 전공만족도(β=-.125, p=.007), 진로성숙도(β=-.459, p<.001) 순으로 나타났다. 이를 토대로 간호보건계열 대학생의 취업스트레스를 줄이기 위해 저학년 때부터 학과별 특성에 맞는 전공지도 프로그램을 마련하고 그에 따른 진로지도가 필요하리라 사료된다.

Since 1990’s, many researches about ultra high performance concrete have been conducted. Compare to conventional concrete, it shows significantly high compressive and tensile strength so that leads to reduce the self weight of structures. However, the use of slender member may meet the buckling failure that is not common phenomenon in concrete structures so far. Most design codes have not suggested any provisions for buckling limit states and very few of researches have been conducted for buckling of concrete girders. In this study, a number of finite element analysis were carried out to investigate the buckling behavior of UHPC I-shaped girders.

This study investigates characteristics on inelastic flange local buckling of ultra high performance concrete (UHPC) plate supported by one edge. The UHPC plate were modeled using 3D shell elements (S4R) and analyzed using by geometric and material nonlinear analysis. The plates for FE analysis were supported by pined and fixed boundary conditions to considering constrained effects of one web. The inelastic local buckling strength from the FE analysis were evaluated according to the flange slenderness ratios. The results shows that material non-linearities of tensile behavior of UHPC highly affects the inelastic local buckling of UHPC plate.

This study investigates elastic flange local buckling of ultra high performance concrete (UHPC) I-girders. The girders were modeled using 3D shell elements (S4R) and analyzed by eigenvalue analysis. Then, the flange local buckling strength from the FE analysis were evaluated according to the flange and web slenderness ratios and compared to the local buckling strength of steel girders. The results shows that the flange local buckling of UHPC I-girders are underestimated compared to the strength of steel girders which has same geometric cross sections and further studies needed related to this field.

This study investigates the flexural shear strength of ultra high performance concrete I-girder. The effect of aspect ratio on the flexural - shear strength of UHPC was analyzed using finite element analysis. The UHPC I-type girder was modeled using 3D shell elements and analyzed using geometric and material nonlinear analysis. The boundary condition is simple support condition and a displacement load is applied to the center of the upper flange. The results shows that shear strength decreased as the aspect ratio increased and the bending-shear failure of UHPC I-girder does not occur even at larger moment than ordinary concrete due to the cross-linking action of steel fiber.

Prestress is a reinforcement method to control crack due to moment on concrete girders with low tensile strength. In the existing literature, it is mentioned that prestress for ordinary concrete affects not only crack control but also shear strength enhancement. As the construction material improves, UHPC(Ultra-HIgh Performance Concrete) with excellent strength and ductility has been developed by combining ultra-high strength concrete and steel fiber. However, study on the effect of prestress on the shear strength of UHPC with different material properties from ordinary concrete is lacking. Therefore, in this paper, the effect of prestress on the shear behavior of UHPC I-girder is studied by finite element analysis. As a result of the analysis, it has been confirmed that the prestress increases crack strength and shear strength of UHPC.

Recently, for efficiency increase of the wind turbine tower, turbine has been enlarged and installation location has been transferring to offshore. The importance of the support structure is emphasized when a wind turbine tower is installed on offshore. The support structure is influenced not only by the system operating loads but also by various marine condition loads. Accurate and safe design is essential because the connection between the support structure and the wind tower can be relatively fragile. In particular, the type of foundation pile and sleeve grout connection were adapted from DNV, API, and ISO that are typically used for wind towers, and they have been continuously studied by many researchers. However, the experimental results by researchers are different from the design equations, and it needs to modify the formula according to connection properties and material. Therefore, this study investigates the design equation presented in existing design criteria and the results of research conducted by existing researchers, and analyzes ultimate strength and failure modes.

Displacement response of structure is valuable information for monitoring an structure integrity. However, measuring the displacement response is difficult than other structure responses, such as acceleration, strain, and angle. So, previous researches have focused on displacement estimation technique using measured acceleration. The displacement estimation methods also have weakness that filtering noise of measured data is so complicate. The estimated displacement might be diverged because of the measuring noise. Because of these reasons, this study focused on rotation angle. This study developed a algorithm for estimating displacement and structure deformed shape using rotation angle.

In this study, elastic flange local buckling strength of doubly symmetric I-girder subjected to bending moment were evaluated by 3D finite element analysis. The analysis model were modeled by 3D shell elements(S4R) using ABAQUS 6.13 program. And loading and boundary conditions were determined by equal end moments and simple boundary conditions. Flange and web slenderness ratio were considered in the parametric studies to evaluate flange local buckling strength with AISC design equations. Then, AISC design equations and characteristics of Elastic flange local buckling of I-girder were evaluated.

Concrete has been widely used for material of bridge girder. However, Concrete is considered as inefficient material for long-span girder. Because it has low material strength compared with those of steel girder, huge cross sectional area are required to have same strength of steel girder bridges. UHPC(Ultra High Performance Concrete) as new material is developed to supplement this weakness of concrete. UHPC has high compressive strength and show softness behavior due to it is reinforced by fiber. If UHPC has no any reinforcement for shear, diagonal tension crack failure is dominant like normal concrete. So, reinforcement for shear is essential and prestress is efficient method of reinforcement for UHPC due to high compressive strength. However, design equation for shear strength suggested by K-UHPC Certification(2012) do not consider prestress effect. Therefore, this study investigate effect of prestress for shear strength of ultra high performance concrete I-girder by using finite element analysis program

Grouted connections have been widely used for offshore structures such as connection method of jacket and mono-pile structures. It is recommended high strength concrete for grouting between pile and sleeve because it is so rapidly hardening that helpful to fatigue strength. This study investigates axial strength of pile to sleeve grouted connections made by 130MPa of high strength concrete. Push-out test were performed to evaluate the axial strength of the grouted connections with different shear-key spacing.

레몬그라스 분말을 첨가한 머핀의 품질특성 및 항산화를 측정하기 위하여 레몬그라스 분말 0%, 1%, 3%, 6%, 9%를 첨 가하여 머핀을 제조하였다. 머핀의 높이, 부피 및 비체적은 분말의 첨가량이 증가할수록 감소하였다. 레몬그라스 분말 첨가군의 수분 함량과 점도는 대조군과의 유의적 차이가 나 타내지 않았으며, 색도 측정 결과, 명도와 황색도는 레몬그라 스의 농도가 증가할수록 유의적으로 감소하였으나, 적색도는 증가하였다. Texture를 측정한 결과, 레몬그라스 분말의 씹힘 성은 첨가량이 증가할수록 감소하였다. 관능검사는 색, 향, 맛, 조직감, 기호도를 측정했으며, 그 결과 3% 첨가군에서 가 장 높은 관능검사 결과를 보여주었다. 레몬그라스 머핀의 DPPH 라디칼 소거능 측정 결과, 레몬그라스의 농도가 증가함에 따라 유의적으로 항산화 활성이 증가하였으므로, 레몬그라스의 첨 가가 머핀의 기능성에 좋은 영향을 나타낼 것으로 사료된다.

가을 울금의 품질향상을 위한 시비수준에 따른 생육특성을 조사하고, 생리활성물질의 변화를 알아본 결 과 아래와 같다. 가을 울금 정식 70일 후 지상부의 초기생육에서 주당 생체중은 시비수준 2배 처리구에서 131.5g으로 가장 무거웠으며, 초장 역시 생체중과 같은 결과로 2배 처리구에서 가장 길게 나타났다. 엽면 적 또한 시비수준 2배 처리구에서 가장 넓어지는 경향을 보였다. 정식 120일 후 생육 중기와 정식 180일 후 후기 생육에서는 지상부의 생체중, 초장, 엽면적, 총엽수 등의 생육 결과가 시비량이 증가할수록 양호 해지는 양상을 보였으며, 생육초기의 결과와 다소 차이를 보였다. 정식 180일째 근경중은 1/2배 처리 58.2g, 1배 처리 142.2g, 2배 처리 95.1g, 4배 처리 79.1g으로 1배 처리에서 1/2배 처리에 비해 약 244%, 4배 처리에 비해 180% 무거운 것으로 나타났다. 시비수준에 따른 가을 울금 근경의 curcumin의 함량은 시비수준이 증가함에 따라 curcumin, demethoxycurcumin, bisdemethoxycurcumin의 농도가 유 의성 있게 증가한 것으로 나타났다. 가을 울금의 curcumin 함량 증가를 위한 시비수준은 1배 처리가 가 장 적합할 것으로 사료된다. 시비수준에 따른 근경의 항산화 활성물질은 2배 처리에서 총 phenol 함량이 11.1mg/100g으로 가장 높았으며, 1배 처리에서 가장 낮았다. Flavonoid 함량은 1배 처리에서 8.50mg/100g으로 가장 높았으며, 4배 처리에서 5.30mg/100g으로 시비수준이 증가함에 따라 감소하는 경향이었다. Oxalic acid, tartaric acid, malic acid, citric acid 등 유기산은 시비수준이 증가함에 따라 그 함량도 증가하는 경향을 보였다.