• Journal of the korean Society of Automotive Engineers
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• v.5 no.1
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• pp.17-23
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• 1983

현재 생산되고 있는 8 ton 차축(후료)의 강도를 평가하기 위해 strain gauge에 의한 능력측정과 이 제품의 신뢰성 향상을 위한 피로 시험기에 의한 시험 및 특히 용접부분의 결함을 검출하기 위한 비파괴검사법의 적용 등, 제품에 대한 품질보증을 위한 일련의 시험을 한 결과를 보고하 고자 한다.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.399-404
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• 2008

The objective of this study is to develop the predicting method of concrete strength when remove concrete form-work without making cement test piece at construction site. For this purpose, this study catches the Maturity Method by using RFID, the usability of which is now being emphasized at site, accumulates and record the strength data, which can be gained with the results of existing Maturity Method method that is accompanied with strength estimation study, in database, and finally proposes the system structure which can check the estimated strength by Maturity Method. The merits of this method by using of Maturity Method are as follows; More objective, precise, and rapid decision can be made to the concrete strength and about the maintaining period of concrete form and form support. More efficient control of integrated material management system can be possible. Architectural field example using RFID can be suggested more concretely. RFID applicability can be extended by using DB of material integration management system.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.465-470
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• 2008

This paper introduces experimental investigates of an electrical accident of the distributing cable termination with simulated badness construction. We prepared two termination kites, one is built-up type, the other is heat contraction type. Also, we manufactured cable termination that have simulated defect by badness construction and measured their insulation characteristics such as ac (35kV, 1min) and impulse (95kV, $1.2{\times}50{\mu}s$) withstand test. The influence of defects such as thickness and the gap between stress-con of housing and semi-conductor on insulating properties of the termination have been studied. The thickness decrease of insulator decreases ac breakdown strength. Dielectric breakdown traces of insulator that is damaged by knife displayed other shape. The gap of between housing and semiconductor deteriorates dielectric strength of insulator seriously.

• Journal of the Earthquake Engineering Society of Korea
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• v.17 no.1
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• pp.43-51
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• 2013

In this paper, analytical models for reinforced concrete shear wall systems designed based on Korean Building Code (KBC2009) are proposed, which have special and semi-special seismic details and are compared with experimental results for a verification of analytical models. In addition, semi-special seismic details aimed to improve constructability and enhance economic efficiency were proposed and evaluated. The analytical models were performed based on nonlinear static and dynamic analysis. Through the nonlinear analyses, two seismic details showed the similar seismic behavior from the cyclic test and the analytical models for the two different seismic details represented the behavior in terms of the initial stiffness, maximum strength and strength degradation. And newly proposed seismic details(semi-special) provided with similar hysterestic behavior as well as the maximum drift.

• Advances in nano research
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• v.3 no.4
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• pp.225-242
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• 2015

The current investigation aims to study performance of geopolymer mortar reinforced with Multiwalled carbon nanotubes upon exposure to $200^{\circ}C$ to $1000^{\circ}C$ for 2 hrs. MWCNTs are doped into slag Geopolymer mortar matrices in the ratio of 0.0 to 0.4, % by weight of binder. Mortar composed of calcium aluminosilicate to sand (1:2), however, binder composed of 50% air cooled slag and 50% water cooled slag. Various water / binder ratios in the range of 0.114-0.129 used depending on the added MWCNT, while 6 wt., % sodium hydroxide used as an alkali activator. Results illustrate reduction in mechanical strength with temperature except specimens containing 0.1 and 0.2% MWCNT at $200^{\circ}C$, while further increase in temperature leads to decrease in strength values of the resulting geopolymer mortar. Also, decrease in firing shrinkage with MWCNT up to 0.1% at all firing temperatures up to $500^{\circ}C$ is observed, however the shrinkage values increase with temperature up to $500^{\circ}C$. Further increase on the firing temperature up to $1000^{\circ}C$ results in an increase in the volume due to expansion.

• Land and Housing Review
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• v.6 no.1
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• pp.21-29
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• 2015

Coupling beams posses proper strength, stiffness and ductility capacities to resist efficiently under seismic loads. The strength, stiffness and ductility capacities for special diagonally reinforced concrete coupling beam with a span-to-depth ratio 2.0 or less is higher than those of coupling beam with conventionally reinforced concrete coupling beam. However, diagonally reinforced detailing creates major construction problem. In this study, design alternatives for diagonally reinforced concrete coupling beams were experimentally investigated. The results show that angle reinforced coupling beam(specimen SA) exhibited a better stable behavior in comparison with non-diagonally coupling beams(specimens SB-series) and sustained corresponding drift ratio, peak-to-peak stiffness and cumulative dissipated energy in comparison to diagonally coupling beam(specimen CA).

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.38-43
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• 2012

Sound absorption capability and mechanical properties such as MOE and MOR in bending of miscanthus particle based board were estimated by the two microphone transfer function method and three point bending method, respectively. The results are summarized as follows: The sound absorption coefficients of miscanthus particle based board was higher than those of commercial gypsum board which is well used as sound absorbing barrier. The MOR and MOE of miscanthus particle based board increased with increasing of board density. The sound absorption coefficients of miscanthus particle based board were 50~80% in the frequency range of about 1~2.5 Khz. In entire frequency range, those value increased with target board density decreasing.

• Korean Journal of Human Ecology
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• v.21 no.2
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• pp.181-195
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• 2012

The purpose of this study was to explore clusters of married woman based on family differentiation and family rules originating from their family of origin, and to examine family strength according to clusters. The research instrument comprised of a questionnaire completed by 269 married women that investigated family differentiation and family rules based on family origins, and the comparative strength of their nuclear family. Analysis of subgroups was based on four representative categories differentiating family rule patterns. Cluster analysis demonstrated that the higher family differentiation level and lower-mid family rules level were related to greater family strength. As a subgroup, lowest levels of family strength were associated with lower family differentiation and lower family rules in all clusters. Findings supported the efficacy of a typological approach for investigation of experiences of married women based on family origin.

• Journal of Families and Better Life
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• v.27 no.2
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• pp.305-316
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• 2009

The purpose of this study was to investigate how children from low-income families perceived their family strength, ego-resilience and school adjustment. The relative magnitude of effects of family strength, ego-resilience and school adjustment were compared. Data were collected from 217 children in grade 4 through 6 who were attending local child welfare centers located in Seoul, Korea. The key research findings were as follows. Ego-resilience and perceived family strength were related to school adjustment among children in poverty. The relatively greater effect of ego-resilience implied that programs for children in poverty need to focus on developing interpersonal relationship skills or coping strategies designed to enable children from disadvantaged environments to deal with stressful events and to promote their ego-resilience. Additionally, the recovery or enhancement of family strength and ego-resilience will be effective at protecting and solving various adaptive problems that children from low-income families may experience at school.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.129-134
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• 2000

Recently, HIPS(High Impact Polystyrene) materials are spot-lighted as office equipment, home electronics, electronics appliances housing, packing containers, etc. But its using are occur to problem caused by fatigue fracture. However, its strength is larged affected by environmental conditions. So, in this paper it tried to analyze the effect of temperature by tensile test and fatigue test. It was observed that yield strength and ultimate strength, fatigue life of same stress decreased relatively with increase temperature. Further, this paper predict S-N curve using the result of tensile test and micro vickers hardness test. For this purpose, the management in the engineering department is able to design the fatigue life of HIPS(HR-1360) materials.