• 한국구조물진단유지관리공학회 논문집
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• 제25권6호
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• pp.262-269
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• 2021

본 논문은 SD700 확대머리철근의 겹침이음을 이용한 단차가 있는 보의 접합상세를 개발하기 위하여 실시한 구조성능평가 실험결과를 나타낸다. 실험변수는 주철근의 겹침이음길이, 철근 항복강도, 단부정착상세 등이다. 모든 실험체에 대하여 춤이 작은 보(B2)의 하부 주철근은 확대머리철근을 적용하였으며, 춤이 큰 보(B1)의 하부 주철근은 일자형 확대머리철근, 90° 갈고리형 확대머리철근 등 두 가지 상세로 이음방법을 적용하였다. 실험결과, SD500과 SD600을 적용한 실험체들은 겹침이음부에서 모두 휨파괴되었으며, 이로 인하여 최대내력은 유사하게 나타났다. SD500을 적용한 실험체들에 대하여, B1의 주철근을 90°갈고리형 확대머리철근으로 적용한 상세가 확대머리철근에 비하여 겹침이음부의 수평균열을 억제하였다. SD700의 확대머리철근을 사용한 실험체는 취성적인 정착파괴가 나타났으며, 겹침이음길이의 증가에 따라 최대내력이 증가하였다. SD700의 확대머리철근을 사용한 실험체들은 실험체정착길이/이론정착길이에 대한 실험내력/이론내력이 ACI 318-19 식은 1.30~1.48로 나타났으며, KDS-2021 식은 1.14~1.30로 평가되었다. 이를 볼 때, ACI 318-19 산정식이 보다 보수적으로 정착길이를 평가함으로써 더 큰 안전율을 가지고 있었다.

• Steel and Composite Structures
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• 제46권4호
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• pp.451-469
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• 2023

The use of precast hollow-core slabs (PCHCS) in civil construction has been increasing due to the speed of execution and reduction in the weight of flooring systems. However, in the literature there are no studies that present a finite element model (FEM) to predict the load-slip relationship behavior of pushout tests, considering headed stud shear connector and PCHCS placed at the upper flange of the downstand steel profile. Thus, the present paper aims to develop a FEM, which is based on tests to fill this gap. For this task, geometrical non-linear analyses are carried out in the ABAQUS software. The FEM is calibrated by sensitivity analyses, considering different types of analysis, the friction coefficient at the steel-concrete interface, as well as the constitutive model of the headed stud shear connector. Subsequently, a parametric study is performed to assess the influence of the number of connector lines, type of filling and height of the PCHCS. The results are compared with analytical models that predict the headed stud resistance. In total, 158 finite element models are processed. It was concluded that the dynamic implicit analysis (quasi-static) showed better convergence of the equilibrium trajectory when compared to the static analysis, such as arc-length method. The friction coefficient value of 0.5 was indicated to predict the load-slip relationship behavior of all models investigated. The headed stud shear connector rupture was verified for the constitutive model capable of representing the fracture in the stress-strain relationship. Regarding the number of connector lines, there was an average increase of 108% in the resistance of the structure for models with two lines of connectors compared to the use of only one. The type of filling of the hollow core slab that presented the best results was the partial filling. Finally, the greater the height of the PCHCS, the greater the resistance of the headed stud.

• 가족자원경영과 정책
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• 제27권1호
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• pp.41-52
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• 2023

본 연구는 한국 여성 가구주의 사회위험 인식수준과 이에 영향을 미치는 요인을 분석하였다. 2020년 「사회조사」 데이터를 활용한 분석결과 응답자의 사회적 자본, 인구 사회학적 특징, 경제적 변수가 사회 위험 인식에 영향을 미치는 것으로 나타났다. 특히 제 변수들을 통제한 후에도 여성 가구주의 사회 위험 인식은 남성 가구주의 사회 위험 인식보다 컸다. 여성 가구주의 경우 준법정신 및 위험대처능력과 같은 사회적 자본과 연령, 거주지역, 건강상태와 같은 인구 사회학적 요인과 소득수준, 주택 유형과 같은 경제학적 요인이 사회적 위험 인식에 영향을 미치는 것으로 나타났다. 가족 자원으로서의 사회적 자본의 역할과 기능에 대하여 논의하여, 가정, 지역사회 간의 협력적 관계 속에서 얻어질 수 있는 사회적 자본의 축적 방안들을 고안해보고자 한다.

• 대한가정학회지
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• 제35권4호
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• pp.229-242
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• 1997

the purpose of this study is to investigate the effect of household type on human capital enhancement expenditures and to compare the difference in these expenditures between female-hemale-headed and married-couple households. Data for this study were from the 1990-91 Consumer Expenditure Survey(CES) and consisted of a sample of 7,225 married-couple and 1,391 female-headed households with children under age 18. The dependent variable to measure human capital expenditures was the sum of four sub-components-education reading leisure and health care expenditures. Tobit analysis with a dummy variable for household type was used to identify the effect of household type on the dollars spent on human capital expenditures. The effect of household type was significant in human capital expenditures indicating that female-headed households spent significantly less for this category than did married-couple household holding other factors constant. the findings of this study suggested that income from a public assistance program was associated with lesser expenditures on human capital while social security income source was associated with greater human capital expenditures, It was also found that the addition of family members between ages of 6 and 17 positively affected human capital expenditures. Understanding these factors is useful for family resource management professionals who work with female-headed households.

• 한국산학기술학회논문지
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• 제13권6호
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• pp.2797-2803
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• 2012

본 논문은 모르타르에 근입되어 인발하중을 받는 정착판 GFRP 근의 인발거동을 기술하고 있다. 정착판 GFRP 근의 모르타르 시험체를 5개 제작하여 인발시험을 수행하였다. 시험 결과를 검증하기 위해 ANSYS 상용프로그램을 이용한 유한요소해석을 수행하였으며 시험결과와 비교되었다. 시험결과 모르타르에 매입된 정착판 GFRP 근의 파열 파괴강도식은 45도 콘(Cone)파괴 이론 보다는 CCD(Concrete Capacity Design)파괴이론을 적용하는 것이 타당한 것으로 나타났다.

• 한국주거학회논문집
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• 제21권1호
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• pp.31-42
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• 2010

The purpose of this study was to analyze behavioral patterns of elderly residents and to identify the characteristics of using furniture and home appliances by elderly-headed households. For this purpose, field studies that included observation and open-ended interview were conducted with 52 elderly-headed households. The major findings of this study were as follows: elderly-headed households need home appliances with lighter body, lower capacity and simple functions. Furniture for elderly people should be designed to minimize the inconvenience of using western style furniture, also the behavior patterns which are important to the elderly like taking medicine have to be considered. And it is necessary to design furniture and equipments properly to prevent accidents happened in housing. Lastly, because the elderly relies heavily on watching TV, it will be desirable to apply TV-friendly devices such as home networking and home automation. Research results will be useful information on product design to reflect characteristics of elderly and follow-up studies associated with each furniture and appliances and specific living behavior are needed.

• 가족자원경영과 정책
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• 제19권4호
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• pp.95-120
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• 2015

This study aimed to investigate the levels of assets and income of male- and female-headed households. A series of analyses of data from the 2013 Korean Household Finance and Welfare Survey on the economic resources of single-parent households were conducted. One of the major findings was that in a comparison between male-headed households and female-headed households, the levels of assets and income in female-headed households were lower than those in male-headed households. The labor income in male households was almost two times higher than that in female households. Housing conditions with respect to male households were more secure and better than those in female households. The factors influencing the levels of economic resources in single-parent households varied in terms of the type of economic resources. Gender, employment status, family characteristics and household income were statistically significant factors with respect to the levels of assets in single-parent households. The level of household income was influenced by gender, education, employment status and the number of household members. The effect of employment status on housing conditions was significant.

• 대한가정학회지
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• 제41권6호
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• pp.91-104
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• 2003

Using the 1998 Survey of Consumer Finances(SCF), this study examined the factors associated with the probability of saving by female-headed households in the U.S, and investigated how these factors differ by life cycle stages. Age of children, age of female householders and their retirement status were used to categorize three life cycle stages: first stage - have at least one child under age 18; second stage - under the age of 62 and have no children under age 18; third stage - over the age of 62 and retired. Logistic regression analysis results indicated that those with higher education and income and who were White were more likely to save. An interactive model showed that life cycle stages were significantly related to saving decisions. Female-headed households in the first stage or the third stage were less likely than those in the second stage (reference group) to save. For female-headed households in the first stage and the third stage, the amount of income had significantly positive effects on the decision to save. Also, in the group of households in the first stage, the receipt of welfare assistance increased the probability of saving.

• Steel and Composite Structures
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• 제48권2호
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• pp.131-143
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• 2023

The CFRP bar was used to achieve more ductile and durable headed-stud shear connectors in composite components. Three series of push-out tests were firstly conducted, including specimens reinforced with pure steel fibers, steel and CFRP bars. The distributed stress was measured by the commercial PPP-BOTDA (Pre-Pump-Pulse Brillouin optical time domain analysis) optical fiber sensor with high spatial resolution. A series of numerical analyses using non-linear FE models were also made to study the shear force transfer mechanism and crack response based on the test results. Test results show that the CFRP bar increases the shear strength and stiffness of the large diameter headed-stud shear connection, and it has equivalent reinforcing effects on the stud shear capacity as the commonly used steel bar. The embedded CFRP bar can also largely improve the shear force transfer mechanism and decrease the tensile stress in the transverse direction. The parametric study shows that low content steel fibers could delay the crack initiation of slab around the large diameter stud, and the CFRP bar with normal elastic modulus and the standard reinforcement ratio has good resistance to splitting crack growth in headed stud shear connectors.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.233-238
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• 2002

This study presents failure mechanisms for the pull-out strength of headed reinforcement for upper bound solution based on the limit theorem. The failure mechanisms to be presented follow the failure surface pattern of punching shear failure found in the joints of slab with a column. Several failure surfaces of the mechanisms have different characteristics for dissipation works and these mechanisms are able to interpret the role of bar details surrounding headed reinforcement.