• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.1
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• pp.156-164
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• 2010

A total of 6 stepwise constructions were made for building the floating mass concrete foundation. The optimal curing strategies and specialized construction guidelines were adoptively extracted from the 1.5m cube mock-up test prior to the main concrete work. Two different thermal crack index(TCI) calculations from current construction manual exhibit relatively low values as comparing the measured temperature data. This implies that the hydration-induced cracking could be developed in parts of concrete mass. However, the controversial phenomenons in reality were observed. No significant surface cracks are detected at the successive construction stages. Thereby, this paper raises the question regarding on the existence of characteristic length with varying size and shape of a target specimen which are missing in the current construction manual. The isothermal core area and high thermal gradient area in the edge volume should be identified and be introduced to TCI calculation for the purpose of an accuracy.

• Journal of the Korean GEO-environmental Society
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• v.18 no.5
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• pp.45-53
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• 2017

IPM bridge was developed to revise the problems of IAB bridge by Nam et al, (2016). This research conducted the p-y analysis to examine the parameter traits among the protruded length (H), penetrated length (L) of pile bent and soil conditions. From the results, the maximum bending moment happened in the top segment of pile bent, because it is integrated to the upper structure. Also, the maximum shear force was shown in the boundary of the sand and weathered soil zones according to the analysis soil conditions. The maximum member force and unbraced length is converged when the ratio (L/H) of protruded length (H) and penetrated length (L) is 1.0. The larger material force is happened, if the pile bent is penetrated shallowly compared to the protruded length. The definite inflection points were shown in the horizontal displacement curve from the p-y analysis, also the smaller penetrated length made the curve grade slower.

• Journal of the Korean association of regional geographers
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• v.23 no.1
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• pp.1-22
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• 2017

This paper is to consider conceptually a formation of food-networks and border-crossing of transnational marriage migrant households on the basis of actor-network theory, and to analyze empirical data on the issues collected by interview with marriage migrant women living around Daegu, S.Korea. Some research results can be argued as follows: First, food can be seen, not as a single material object, but as a multiple and hybrid network of human and nonhuman (material and institutional) actors, in which activities of food cooking and eating are regulated by and (re)construct social relations and placeness of households. Secondly, food-networks in marriage migrant households implement relationships of micro-power (and attachment) in the process of its (re)formation, and hence the food-network, it can be argued, is a field of power in which conflicts and compromising around food cooking and eating are intersecting each others. Thirdly, food-networks in marriage migrant households in both their origin country and in the Korean home are not only affected by macro natural and social environments but also by micro placeness of the households, both of which constitute the food-networks and operate in relations with other actors in the netwroks. Finally, food-networks in marriage migrant households reflect multiple and multi-scalar spatial mobility and placeness of transnational food culture, through which they express topologically 'fluid space' and 'absent presence', in which marriage migrant women can (or cannot) conduct social and cultural border-crossing.

• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.382-392
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• 2021

Purpose To evaluate the ultrasonographic characteristics of steatocystomas focusing on the features that aid in differentiating them from epidermal inclusion cysts and lipomas. Materials and Methods The ultrasonographic findings of 14 histologically proven steatocystomas in 10 patients were retrospectively reviewed. The following features were assessed: the layer of involvement, shape, margin, echogenicity, posterior acoustic features, and the presence of a visible wall or intralesional striations. The findings were compared with those of subcutaneous lipomas and epidermal inclusion cysts to identify those findings that aid in the differential diagnosis of steatocystomas. Results The majority of steatocystomas appeared as a subcutaneous mass (n = 6, 42.9%) or a mass involving both the dermal and subcutaneous layers (n = 6, 42.9%). Steatocystomas exhibited a well-defined smooth margin (n = 12, 85.7%) and homogeneous echogenicity (n = 9, 64.3%), and showed no specific posterior acoustic features (n = 9, 64.3%). The most important features that differentiated steatocystomas from epidermal inclusion cysts were a homogeneous internal echotexture (p = 0.009) and absent or less prominent posterior acoustic enhancement (p < 0.001). The features that distinguished steatocystomas from lipomas were the margin (p < 0.001), echogenicity (p = 0.034), internal echotexture (p = 0.004), and the absence of intralesional striations (p < 0.001). Conclusion Steatocystomas appeared as well-defined homogeneous masses with mild or absent posterior acoustic enhancement.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.2
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• pp.123-130
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• 2015

This paper presents a new formulation for transient simulations of microwave propagation in heterogeneous unbounded domains. In particular, perfectly-matched-layers(PMLs) are introduced to allow for wave absorption at artificial boundaries used to truncate the infinite extent of the physical domains. The development of the electromagnetic PML targets the application to engineering mechanics problems such as structural health monitoring and inverse medium problems. To formulate the PML for plane electromagnetic waves, a complex coordinate transformation is introduced to Maxwell's equations in the frequency-domain. Then the PML-endowed partial differential equations(PDEs) for transient electromagnetic waves are recovered by the application of the inverse Fourier transform to the frequency-domain equations. A mixed finite element method is employed to solve the time-domain PDEs for electric and magnetic fields in the PML-truncated domain. Numerical results are presented for plane microwaves propagating through concrete structures, and the accuracy of solutions is investigated by a series of error analyses.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.4
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• pp.39-49
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• 2001

In this paper, inelastic analysis procedures are presented for the seismic performance evaluation of RC bridge piers with premature termination of main reinforcement. The mechanical characteristic of cracked concrete and reinforcing bar in concrete has been modeled, considering the bond effect between reinforcing bars and concrete, the effect of aggregate interlocking at crack surface and the stiffness degradation after the crack. The smeared crack approach is incorporated. In boundary plane at which each member with different thickness is connected, local discontinuous deformation due to the abrupt change in their stiffness can be taken into account by introducing interface element. The increase of concrete strength due to the lateral confining reinforcement has been also taken into account to model the confined concrete. The proposed numerical method for seismic performance evaluation of RC bridge piers with premature termination of main reinforcement will be verified by comparison with reliable experimental results.

• Korean Institute of Interior Design Journal
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• v.13 no.2
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• pp.100-108
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• 2004

인테리어 디자인학은 보편적으로 건물의 내부공간, 즉 매우 명확한 경계들을 전제로 잘 정의된 공간들에 관한 연구로 그 범위가 제한되어져 왔다. 따라서 건축, 도시, 또는 매우 광대한 의미에서의 환경디자인의 특권으로 알려져 있는 도시에 관한 쟁점을 그다지 자주 다루지 않는 편이라 할 수 있겠다. 그러나 극도로 고밀도화된 현대의 대도시들은 주요 지하 교통망을 중심으로 상업, 유흥, 업무시설 그리고 경우에 따라서는 주거단지에 까지 쉽게 연결되는 거대한양의 전이 실내공간들을 창출해내고 있다. 이것이 최근 홍콩의 건축가 게리 챙(Gary Chang)에 의해서 규정된 새로운 개념의 고밀도 도시 인테리어 랜드스케이프(interior landscape)인 것이다. 이러한 인테리어스케이프의 개념은 현대 도시의 모습 중에서 가장 흥미로운 개념들 중의하나라 할 수 있는데 다양한 요소들이 혼합된 그 특성은 이제 사회학, 건축, 인류학, 도시탐험, 인테리어 디자인, 도시 그리고 환경 디자인 등 다양한 분야에서 뜨거운 논쟁의 주제로 떠오르게 된 것이다. 이제 도시에 관한 연구는 더 이상 외부에서 내부로 진행되는 것이 아니고, 내부에서부터 출발되는 것이다. 극도로 밀집된 아시아의 대도시들은 이렇게 혼잡한 도시환경의 모든 요인들을 더 잘 이해할 수 있도록 다양하고 흥미로운 상황들을 제공해 주고 있다. 상업적 목적으로 건물 전체를 사용하는 수직적 전략이나 다양한 문화적 행태들은 도시 환경의 '혼잡성'을 그냥 참을만한 것이 아니라 오히려 그 도시만의 매력적 요소로 부각시켜 주는 것이다. 본 논문은 인테리어스케이프를 중심으로 진행되고 있는 다양한 이론적 논쟁들의 분석에 그 기초를 두고 있다. '장소성의 부재'의 개념, 혼잡의 문화, 공공공간의 사유화, 결절도시, 한계의 개념들을 분석하여 아시아 대도시들이 어떻게 이러한 쟁점들을 그들 자신만의 고유한 해결책으로 발전시키는지를 고찰하고자 한다. 본 논문의 목적은 서울을 사례분석 중 하나로 사용하여 인테리어 디자인 분야의 경계를 대도시로 확장하는 동시에 새로운 적용영역의 가능성을 탐구하는데 있다 하겠다.

• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.5-19
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• 2014

In this study, the structural analysis is performed on the method of shallow block and deep cement mixing pile, and then their characteristics and associated behaviors were analyzed. In the case of continuous beam analysis, the predicted settlement was very small, and shear force and bending stress are somewhat overestimated. The frame method is similar to numerical analysis in the internal force shallow block and long pile, but because the settlement of pile is underestimated, the additional calculation using the reaction of the long pile is necessary. For soil arching method and piled raft foundation method, the excessive axial force of long pile was predicted because the load sharing of pile is very large compared to the other methods. In the behavior of the shallow block and deep pile method, the settlement of shallow block and contact pressure are much in the center than the edge. In the estimating method considering the interaction between improved material and ground, the load sharing of the soil-cement pile ranges from 20% to 45%, and the stress ratio is 2.0~5.0 less than piled DCM. The maximum member forces at the boundary conditions of pile head are similar, but in fixed head the axial force and vertical displacement are different in accordance with pile arrangement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2505-2510
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• 2013

Parametric studies on nonhomogeneous pile and homogeneous pile installed in clay were performed through the developed technique to investigate the effects of considered factors on the lateral pile behaviors. Values of the parameters with embedment depths of the two piles having different flexural rigidity show that values of the parameters for more rigid pile were greater than those for smaller one. Parameters for the case of the nonhomogeneous pile were converged to the same ones of the homogeneous pile as nodal point moves away from point of material boundary. In order to determine adequate upper length of the nonhomogeneous pile, changing patterns of the parameters, lateral displacement, member forces and so forth should be compared.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2032-2037
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• 2009

The load carrying capacity of bridge structures in public use is generally evaluated without considering their actual behavioral characteristics. This study examined common errors taking place in the evaluation of load carrying capacity of bridge structures. In order to account for their current behavioral characteristics such as the boundary condition, we evaluated the load carrying capacity of a bridge in terms of axial force, which was calculated by applying deflection to the buckling equation for members with initial imperfections, and in terms of bending moment obtained from deflection.