• 한국가스학회지
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• 제22권5호
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• pp.100-106
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• 2018

국내산업단지 내 고압 매설배관은 장기사용배관이 많고 독성 가연성 불활성 등 고압가스는 물론 다양한 유해화학물질이 한도로 내에 복잡하게 매설되어있어 다양한 타공사 등 사고 발생 시 인접하여 매설된 다른 배관에 손상을 미칠 수 있어 높은 수준의 안전관리가 요구되고 있다. 이에 본 연구에서는 고압가스매설배관과 도시가스매설배관 안전관리실태를 심층비교분석을 통하여 고압가스 매설배관의 효율적인 안전관리방식 도출에 활용하고자한다.

• 한국레이저가공학회지
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• 제17권3호
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• pp.19-23
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• 2014

To directly engrave circuit-line patterns as wide as $6{\mu}m$ in a buildup film to be used as an IC substrate, we applied a projection ablation technique in which an 8 inch dielectric ($ZrO_2/SiO_2$) mask, a DPSS 355nm laser instead of an excimer laser, a ${\pi}$-shaper and a galvo scanner are used. With the ${\pi}$-shaper and a square aperture, the Gaussian beam from the laser is shaped into a square flap-top beam. The galvo scanner before the $f-{\theta}$ lens moves the flat-top beam ($115{\mu}m{\times}105{\mu}m$) across the 8 inch dielectric mask whose patterned area is $120mm{\times}120mm$. Based on the results of the previous research by the authors, the projection ratio was set at 3:1. Experiments showed that the average width and depth of the engraved patterns are $5.41{\mu}m$ and $7.30{\mu}m$, respectively.

• 비파괴검사학회지
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• 제20권4호
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• pp.305-313
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• 2000

콘크리트 내부에 위치한 철근과 공동의 탐사 성능을 파악하기 위해, 상용 비파괴 검사 장비를 이용한 측정과 이론적 모델링을 실시하고, 향상된 신호처리 결과의 예를 제시하였다. 실측에 사용된 장비는 레이더 장비 2종과 전자기법 철근 탐사 장비 2종이다. 철근 탐사에는 직경 19mm의 철근을, 그리고 공동 탐사에는 두께 50 mm의 스티로폼을 콘크리트 시험체 안에 각기 다른 피복 두께로 매립하여 측정하였다. 또한, 철근의 수평 배근 간격 탐사를 위해 두 개의 철근을 매립 측정하였다. 실험과 함께 전자기파 모델링 방법을 소개하여, 레이더를 이용한 경우, 철근과 공동이 탐지되는 과정을 이론적으로 보여주었다. 탐사능을 향상시키기 위해, 상용 레이더 장비의 측정 결과를 신호처리 과정을 통해 개선하였다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.255-261
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• 1998

The recent greenhouses are extremely light-weight structures and easily damaged by the strong winds due to the lack of uplift capacity of pile foundations. The uplift capacity of pile foundations are subject to the shape of the pile surface, diameter, weight, and embedded depths. etc. So, it is very important to figure out the most appropriate conditions on shape of the pile surface and it's embedding depths. to improve wind proof capability of pipe greenhouses. In this study, plane and corrugated pile surfaces were examined on their uplift capacity with 30 to 50 cm of embedding depths. The diameters of tested piles were 10 cm, 15 cm, and 20 cm, respectively. Compaction ratio of the tested soil was 80%. Each test run was repeated three times for the respective treatment. Obtained results are as follows; In all cases, as the diameter and the embedding depth were increased, the ultimate uplift capacity of the pile was also increased. And it was clear that the ultimate uplift capacity of corrugated pile was approximately two times as big as that of plain piles under same conditions.

• Geomechanics and Engineering
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• 제8권3호
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• pp.441-460
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• 2015

A new theoretical approach for analysis of stress around a tensioned anchor in rock is presented in this paper. The solution has been derived for semi-infinite elastic rock and anchor and for plane strain conditions. The method considers both the anchor head bearing plate and its grouted bond length embedded in depth. The solution of the tensioned rock anchor problem is obtained by superimposing the solutions of two simpler but fundamental problems: A distributed load applied at a finite portion (bearing plate area) of the rock surface and a distributed shear stress applied at the anchor-rock interface along the bond length. The solution of the first problem already exists and the solution of the shear stress distributed along the bond length is found in this study. To acquire a deep understanding of the stress distribution around a tensioned anchor in rock, an illustrative example is solved and stress contours are drawn for stress components. In order to verify the results obtained by the proposed solution, comparisons are made with finite difference method (FDM) results. Very good agreements are observed for the teoretical results in comparison with FDM.

• Steel and Composite Structures
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• 제15권4호
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• pp.357-377
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• 2013

In order to study the degradation and damage behaviors of steel frame welded connections, two series of tests in references with different connection constructions were carried out subjected to various cyclic loading patterns. Hysteretic curves, degradation and damage behaviours and fatigue properties of specimens were firstly studied. Typical failure modes and probable damage reasons were discussed. Then, various damage index models with variables of dissipative energy, cumulative displacement and combined energy and displacement were summarized and applied for all experimental specimens. The damage developing curves of ten damage index models for each connection were obtained. Finally, the predicted and evaluated capacities of damage index models were compared in order to describe the degraded performance and failure modes. The characteristics of each damage index model were discussed in depth, and then their distributive laws were summarized. The tests and analysis results showed that the loading histories significantly affected the distributive shapes of damage index models. Different models had their own ranges of application. The selected parameters of damage index models had great effect on the developing trends of damage curves. The model with only displacement variable was recommended because of a more simple form and no integral calculation, which was easier to be formulated and embedded in application programs.

• 한국도서관정보학회지
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• 제47권4호
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• pp.43-68
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• 2016

이 글의 목적은 현대 진보사서직 사상의 추세와 다양성을 밝혀서 국내 사서직의 사상적 그리고 정치적 지평을 넓히는데 도움을 주는 것이다. 이 목적을 달성하기 위하여, 미국의 대표적 진보사서인 '조이아 혼(Zoia M. Horn, 1918-2014)'이 자서전에서 기술하고 있는 도서관 자유사상을 귀납적 방법으로 분석하여 결과를 도출하였다. 그 결과, Horn의 핵심적인 도서관 자유사상은 평등, 지적자유, 그리고 인류평화라는 것과 이러한 핵심 사상의 구성요인들을 규명하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.130-133
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• 2006

Owing to Higher story tendency and ceiling hight restriction of recent times, even though the depth of Coupling Beam decreases the demand efficiency is coming to be high rather so it is the difficult to satisfy a demand efficiency with the actual existing RC/Steel condition. It has been researched a lot of methods as an alternative plan about these but designer cannot apply them for the reason ; the structure standard and theory background are not taking a triangular position. As accomplishing the test research about the beams-wall connections department of steel-plate composite coupling beams from the research in the study it examines closely the beams-wall connections conduct quality and tries to provide the fundamental data for reasonable and optimum connection department designs. It knows that connection fixation degree and composite conduct degree of member part together become the important variable showing an energy dissipation ability in Test result.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.538-541
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• 2006

PSC(Prestressed Concrete) box girder bridges have been widely applied in Korea. A number of these bridges have been built by the segmental construction method in the longitudinal direction and(or) vertically along the cross-sectional depth with MSS(Moving Scaffolding System). An actual 2-span continuous PSC box girder bridge of Kyeongbu high speed railway was selected and instrumented with 96 vibrating wire embedded type strain gauges and 2 thermocouples. The long-term behavior of the bridge was monitored through two major points located at mid-span of the first span and at the internal support. Data collection started just after the casting of the first segment (U section). Concrete strain and temperature data were gathered regularly by a data logger (CR10) during 600 days under and after construction. According to this measurement, the parabolic longitudinal strain distribution in the top slab at mid-span is shown. And also, the same distribution at the interior support is shown. The compressive strains at the cantilever region are larger than at the web position and the internal part in the top slab. Strain difference largely happened during the early construction period.

• Human Ecology Research
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• 제58권3호
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• pp.375-390
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• 2020

This paper explored the marriage migrant mothers' experiences of parenting bi-ethnic children in South Korea based on the concepts of ethnic socialization and intersectionality. We analyzed in-depth interviews of 22 marriage migrant women from Vietnam residing in the capital region of South Korea. They had at least one child whose biological father is Korean. Children were 5 years old or older, attending preschool or elementary school. Five types of bi-ethnic socialization strategies were identified, which provide portraits of different situations in which marriage migrant women were placed. The five strategies that emerged from the data were 1) "Natural practice of bi-ethnic socialization" including two heterogeneous groups, "Coexistence of two cultures" and "Mixture of two cultures", 2) "Active practice of bi-ethnic socialization", 3) "Struggling practice of bi-ethnic socialization", 4) "Silence on bi-ethnic socialization", and 5) "Suppressed bi-ethnic socialization". The strategies of bi-ethnic socialization that marriage migrant women chose to raise their children reflected personal perceptions of Korean society and individual ethnic identity formed within Korean society. This study complements existing research on ethnic socialization by examining how ethnic socialization practices are shaped by multiple contexts marriage migrant women embedded in Korean society.