• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.468-475
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• 2007

The Steel deck a structural analysis in head plate form change the objective bridge which it sells it accomplished a detailed structural analysis from the research which it sees and Bulk-head plate it accomplished. The length rib where the fatigue crack which is considerable generally occurs, width rib connection department and the length rib side, the width rib side it compares principal stress in the object and it does to sleep. It applied the grudge element model which it describes consequently after words and a load and a boundary condition and it executed it compared a static test and principal stress. It grasped the stress conduct of the The Steel deck petal which it follows in hand weaving rib affix location and the affix location to sleep in order to analyze a same location Bulk-head the head and comparison considered. From the detailed section which is reinforced with the stress investigation result hand weaving rib of the location which is weak in structural analysis result fatigue crack of form star reinforcement details basic form and Bulk-head the form which is reinforced with the head plate compared to principal stress investigation hour it is judged at the section which separates most.

• 한국압력기기공학회 논문집
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• 제13권1호
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• pp.75-83
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• 2017

This study investigated deformation behavior of major nuclear structural materials under cyclic loading conditions via cyclic stress-strain test. The cyclic stress-strain tests were conducted on SA312 TP316 stainless steel and SA508 Gr.3 Cl.1 low-alloy steel, which are used as materials for primary piping and reactor pressure vessel nozzle respectively, under cyclic load with constant strain amplitude and constant load amplitude at room temperature (RT) and $316^{\circ}C$. From the results of tests, the cyclic hardening and softening behavior, stabilized cyclic stress-strain behavior, and ratcheting behavior of both materials were investigated at both RT and $316^{\circ}C$. In addition, appropriate considerations for cyclic deformation behavior in the structural integrity evaluation of major nuclear components under excessive seismic condition were discussed.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.10-15
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• 2016

This research was conducted structural analysis in order to analyze the impact of the gear in Urea pump when the water is frozen. Subject of study, gear was designed nine models, this gear is a spur gear, located in pump. Contact conditions and rotation conditions were set the gear's condition of restriction. Given 136 MPa pressure to external gear by water was set to the applied stress. The performing result of structural analysis, maximum stress and strain are appeared between two gears. At the same diameter, strain and stress are decreased gradually thicker. Because of the little part in crevice between gears, this parts of gears could be obtained conclusion to be generated maximum stress and strain.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.267-268
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• 2006

The cylinder cover stud of low-speed marine diesel engine is more than just a stud. It is a large structural element occasionally weighing over 200 kg used for assembling the combustion chamber components. Therefore, to understand the structural behavior of the stud and design it safely is quite important considering a catastrophic failure which can be arisen from an inadequate use of it. In this paper, the analysis results of the structural behavior of the stud is introduced. Strain measurement results compared with FE analysis results are summarized. The results showed that 1) the stud stress increased with engine operating load, 2) the maximum stress amplitude was about 10 MPa which is far smaller than the stud's fatigue strength of 61 MPa, 3) the stress ratio is higher than 0.9 and the stud's load factor is about 20 %, and 4) about 7 % of initial pressure tightening load was reduced while changing to a nut tightened condition.

• 한국공간구조학회논문집
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• 제3권3호
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• pp.85-93
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• 2003

Steel, concrete and their combination materials are the most 6commonly used materials for civil engineering structural systems such as buildings, bridge structures and other structures. Recently, however, fiber reinforced polymer (FRP) composites, a relatively new composite material made of fibers and polymer resins, have been gradually used in structural systems as an alternative structural material. This paper describes a comparison of design strength equations for steel column and FRP composite column based on design philosophies. The safety factors used in allowable stress design (ASD) are relatively higher in FRP structural design than steel structural design. Column critical stress equations of FRP composites column from an experimental study can be represented by Euler elastic buckling equation at the long-range of slenderness, and an exponential form at the short-range of slenderness as defined in Load and Resistance Factor Design (LRFD) of steel column. The column strength of steel and FRP composite columns in large slenderness is independent of material strength, this result verified the elastic buckling equation as derived by Eq. (15) and Eq. (5).

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 봄 학술발표회 논문집
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• pp.93-100
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• 1998

The basic systems of spatial structures such as shells, membrane, cable-nets and tensegrity structure have been developed to create the large spaces without column. These structures may have large freedom in scale and form, and especially tensegrity structures are received much attention from the view points of their light weight and aesthetics. But There re some difficulties concerning structural stability, surface formation and construction method. One of the way to solve these problems reasonably is a combination of tensile members and rigid members. A structural system based on this concept is referred to as the "HTS ( Hybrid Tension Structure )". This is a type of flexible structural system which is unstable initially, because the cable material has little initial rigidity. As cable - dome hybrid structures is a type of HTS, the initial stress for the self- equilibrated system having stable state have to be introduced. To determine initial stress having stable state, the shape finding analysis is required before the stress - deformation analysis. In this paper, the primary objective is to derive the nonlinear finite element formula of cable and truss members considering geometric nonlinearity for shape finding of cable-dome, and to propose the method to decide the initial stress by the shape analysis of cable-dome hybrid structure with the self-equilibrated state.

• 한국학교ㆍ지역보건교육학회지
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• 제13권3호
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• pp.13-31
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• 2012

Purpose: This study was on the structural analysis of the covariant amount in order to evaluate the suitability of the structural models which can explain and predict the mental health of children on the basis of Bronfenbrenner's ecological theory. Methods: A questionnaire was used to survey 269 children from dysfunctional families out of 5th and 6th grade students from 30 elementary schools in one city and 6 counties, which was analyzed by using PASW Statistics 18.0 and LISREL 8.7 programs. Results: The variable which had influence on the self-esteem was the social support. The variable which had influence on the positive reaction under stress was the stress. The variables which had influence on the negative reaction under stress were stress, and self esteem. The variables which had influence on the mental health were the self-esteem and the negative reaction under stress. The main variables to influence the mental health of children from dysfunctional families turned out to be the self-esteem and the negative reaction under stress to the mental health. Conclusion: Evaluating the suitability of the models, I presented the bases on the practical nursing business. They showed the right directions to the mental health care of children from dysfunctional families.

• 한국정밀공학회지
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• 제15권12호
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• pp.28-36
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• 1998

This investigation is the result of a structural analysis by the finite element method and static loading test for the optimal structural design of an electric railway vehicle made of stainless 301L materials. We analyzed the stress and displacement of the existing electric car-body structure for predicting the position of concentrated stress, the flow of stress, rigidity to be occurred in the car-body structure when it is subjected to the vertical load. It was exposed that the side sills and window corners around the bolsters are the weak parts of the electric car-body structure because the bolsters of the electric car-body structure were subjected to the vertical load and dynamic load to be occurred during running. The flow of stress and the cause of stress concentration in the weak zone were studied in order to prevent the concentration of stress and buckling. The rearrangement of the structure and the selection of the beam elements were also carried out for optimum design of the structure.

• 대한조선학회논문집
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• 제39권2호
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• pp.61-68
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• 2002

K-a 관계가 동일하면, 선형파괴역학적 견지에서 균열개구 거동이 같다고 가정할 수 있다. 본 연구에서는 실제 구조물과 같은 K-a 관계를 주는 무한판 관통균열의 응력분포를 등가분포응력으로 정의한다. 실제 구조물과 동일한 K-a 관계가 구현되는 응력분포를 간단한 시험편에 작용시켜, 피로균열전파 해석을 수행하면 실제 구조요소의 피로전파수명 추정이 가능하다. 구조물에 대한 K-a 관계는 유한요소법 등의 이산화 수법 혹은 간이 추정법 등에 의하여 추정이 가능하다. 등가분포응력을 이용하여 유효 균열진전 음력을 구하는 방법의 타당성을 검토한다.

• Human Ecology Research
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• 제59권3호
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• pp.387-400
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• 2021

This study examined the structural relationship between children's academic stress, grit, executive function difficulty, and media device addiction. Data on 1,132 children and their mothers from the 11^th (2018)Panel Study on Korean Children were used for the study. Data were collected by Academic Stress Scale, Grit Scale-Children, Child-Adolescent Self-reported Executive Function Difficulty Screening Questionnaire, and K-Internet Addiction Scale. Data were analyzed using SPSS 25.0 and AMOS 23.0 program with Pearson correlation, structural equation model and bootstrapping. The main results were as follows. 1) Children's academic stress had a negative influence on their grit. 2) Children's grit had a negative influence on their executive function difficulty and media device addiction. 3) Children's executive function difficulty had a positive influence on their media device addiction. 4) The relationship between children's academic stress and media device addiction was mediated by their grit and executive function difficulty. This study is significant in the sense that it found protective factors and risk factors for children's addiction to media devices. We suggest that children's grit be improved, and their academic stress and executive function difficulty be reduced to prevent and mediate children's media device addiction.