• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.331-340
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• 2017

This study was performed in order to develop of the new modular construction system. For the modular construction method that is currently applied in the country, it is very expensive in terms of material costs and fire resistance because it uses only the steel C-type beam. In order to overcome this, and the practical application of new steel-PC hybrid module construction system. Improvement and development of the cross-section of the structural beam member in order to be carried out first. An experiment was carried out by making three specimens. Experiment result, the composite beam was dominated by the horizontal shear failure. It was evaluated through a nonlinear analysis and experimental & theoretical for the structural performance the composite beam member.

• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.2
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• pp.3-12
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• 2001

This paper presents the proposed methods of DE (distinct element) modelling to estimate the stability of tunnels in jointed rock masses. First, the criterion to select the joint set(s) contributed to the discontinuous behaviour in a tunnel section is proposed. Selected joint set(s) is(are) considered to form the edges of distinct elements (rock blocks) and the others to modify the elastic properties of rock blocks. The complex DE model with the average and the deviation of joint orientation and joint length for each joint set was compared to the simple model with only the average of joint orientation and the assumption that joint length is infinite. As a result, the latter is suitable to the purpose of tunnel design because it can show the consistent behaviour of a jointed rock mass such as the locally discontinuous failure and the global anisotropic behaviour.

• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.263-273
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• 1993

The purpose of this study was to analyse the center of resistance of the maxillary first molar using the 3-dimension finite element method. An extracted maxillary first molar of normal shape and average root length was selected and sectioned every 1.5mm parallel to the cementoenamel junction. Each section was traced and digitized to construct 3-D finite element model of the maxillary first molar. After a certain magnitude of counterbalancing moment(M) was applied to the tooth, a varying single force(F) of distomesial direction was applied to a certain point of th tooth until the tooth was translated. The force producing translation(Ft) was substituted to the equation ${\Delta}d=M/Ft$ to calculate the center of resistance of the maxillary first molar. And reducing the alveolar bone level 1.68mm, and 3.36mm below to the cementoenamel junction, the tooth movement was analysed to see the effect of reducing the alveolar bone level to the location of the center of resistance. The results were as follows ; 1. The center of resistance of the maxillary first molar was 3.72mm apical, 1.10mm buccal, and 0.71mm mesial to the geometric center of the horizontally sectioned surface at the cementoenamel junction. This point was 0.36mm apical, 1.20mm buccal, and 0.71mm mesial to the trifurcation point, indicating that it was not on the tooth root. 2. As the alveolar bone level was reduced, the center of resistance of the maxillary first molar was moved to the apical direction.

• Land and Housing Review
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• v.2 no.3
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• pp.277-285
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• 2011

To reinforce bearing capacity-changed section or different foundation in the same building, empirical or simple tools have been used. To solve this problem, an analytical solution which can evaluate and reinforce the stability of foundation is introduced. To suggest a clue for the problems, current foundation reinforcing method is studied through recent literature studies and the structural analyses of foundation slab are performed on the pile foundation of 49$m^2$, 59$m^2$ and 84$m^2$ I type apartments in 15 story building. The analyses are conducted with SAP 2000, a computer program for ordinary structural analysis. To predict the moments of slab by ground non-uniformity, the structural analysis results for the foundation slab of 3 types 15 story apartment buildings in 49$m^2$, 59$m^2$ and 84$m^2$ I type on non-uniformity ground are shown in the diagrams.

• Journal of Biomedical Engineering Research
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• v.31 no.4
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• pp.285-291
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• 2010

Recently, advance on various modalities of diagnosing, prostate volume estimation became possible not only by the existing two-dimension medical images data but also by the three-dimensional medical images data. In this study, magnetic resonance image (MRI), computer tomography (CT) and ultrasound (US) were employed to evaluate prostate phantom volume measurements for estimation, comparison and analysis. For the prostate phantoms aimed at estimating the volume, total of 17 models were developed by using devils-tongue jelly and changing each of the 5ml of capacity from 20ml to 100ml. For the volume estimation through 2D US, the calculation of the diameter with C9-5Mhz transducer was conducted by ellipsoid formula. For the volume estimation through 3D US, the Qlab software (Philips Medical) was used to calculate the volume data estimated by 3D9-3Mhz transducer. Moreover, the images by 16 channels CT and 1.5 Tesla MRI were added by the method of continuous cross-section addition and each of imaginary prostate model's volume was yielded. In the statistical analysis for comparing the availability of volume estimation, the correlation coefficient (r) was more than 0.9 for all indicating that there were highly correlated, and there were not statistically significant difference between each of the correlation coefficient (p=0.001). Therefore, the estimation of prostate phantom volume using three-dimensional modalities of diagnosing was quite closed to the actual estimation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.89-94
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• 2004

A steel plated is typically composed of plate panels. The overall failure of the structure is certainly affected and can be governed by the bulking and plastic collapse of these individual members. In the ultimate limit state design, therefore, a primary task is to accurately calculate the buckling and plastic collapse strength of such structural members. Structural elements making up steel palated structures do not work separately, resulting in high degree of redundancy and complexity in contrast to those of steel framed structures. To enable the behavior of such structures to be analyzed, simplifications or idealizations must essentially be made considering the accuracy need and degree of complexity of the analysis to be used. Generally the more complex the analysis the greater is the accuracy that may be obtained. The aim of this study is the investigation of the effect of the tripping behaviour including section characteristic for a plate under uniaxial compression. For this purpose of study, in used elasto-plasticity deformation FEA method are used for this study.

• Nuclear Engineering and Technology
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• v.42 no.5
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• pp.576-581
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• 2010

KAERI (Korea Atomic Energy Research Institute) fabricated MOX (Mixed Oxide) fuel pellets as a cooperation project with PSI (Paul Scherrer Institut) for an irradiation test in the Halden reactor. The MOX pellets were fitted into fuel rods that included instrumentation for measurement in IFE (Institutt for Energiteknikk). The fuel rods were assembled into the test rig and irradiated in the Halden reactor up to 50 MWd/kgHM. The irradiated fuel rods were transported to the IFE, where ceramography was carried out. The fuel rods were cut transversely at the relatively higher burn-up locations and then the radial cross sections were observed. Micrographs were analyzed using an image analysis program and grain sizes along the radial direction were measured by the linear intercept method. Radial cracks in the irradiated MOX were observed that were generally circumferentially closed at the pellet periphery and open in the hot central region. A circumferential crack was formed along the boundary between the dark central and the outer regions. The inner surface of the cladding was covered with an oxide layer. Pu-rich spots were observed in the outer region of the fuel pellets. The spots were surrounded by many small pores and contained some big pores inside. Metallic fission product precipitates were observed mainly in the central region and in the inside of the Pu spots. The average areal fractions of the metallic precipitates at the radial cross section were 0.41% for rod 6 and 0.32% for rod 3. In the periphery, pore density smaller than 2 ${\mu}m$ was higher than that of the other regions. The grain growth occurred from 10 ${\mu}m$ to 12 ${\mu}m$ in the central region of rod 6 during irradiation.

• Solar Energy
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• v.15 no.3
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• pp.59-73
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• 1995

The thermal analysis is accomplished with the route for the underground power transmission system which adopts the water pipe cooling with trough in tunnel. As a result, in case of a cooling system based on a refrigerator, the optimum condition for the flow rate of cooling water and the air velocity are calculated as the $2{\sim}3{\ell}/s/pipe$ and $1{\sim}2m/s/fan$, respectively. On the other hand, in case of cooling tower the optimum condition for them are calculated as the $2{\sim}3{\ell}/s/pipe$ and 6 m/s/fan, respectively. But the cooling system based on a cooling tower has the problem of enlarging the size of cooling fan and suppressing the labor of operator in tunnel. Therefore, to meet all the cooling conditions for a given cooling section, the cooling system based on a refrigerator is more acceptable.

• The Journal of Fisheries Business Administration
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• v.35 no.2
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• pp.1-29
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• 2004

This paper aims to understand the points which the Board of Directors of the National Federation of Fisheries Cooperatives System has proposed, and to find some improvement. This Fisheries Cooperatives previously had a single board system operating two small board rooms which became independent within the two sectors of credit and .provision in addition to the existing board of directors. This is a very unique board of directors system which is not found in cooperatives in our country nor in the business world. This change of the board of directors of the Fisheries Cooperatives is ascribed to the reorganization of the system into a completely independent division system, which operates business separately based on each sector as opposed to the previous multiple cooperatives system. However, a plural board of directors system does contribute to the improvement of managerial efficiency by strengthening the self-control of each independent business section, but deepens conflicts between its internal organizations, and brings about a reverse function which might deteriorate both the controlling power of a systematic organization and the coordinating power between sectors. This paper made an analysis of acceptors' attitudes toward the board of directors of the fisheries cooperatives system by regulating all the staff directly related to the operation of the board of directors of the fisheries cooperatives system as a group of acceptors and by selecting one hundred and fifty persons among the staff as a sample. The inquiry into acceptors' attitudes was made using questionaries, and the data for this investigation was processed and analyzed using a statistical method. The contents of this paper are composed of I. an introduction, II. the findings of the questionary investigation, III. the overall opinion for the improvement of the board of directors system, and IV. a summary and conclusion.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.503-514
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• 2015

This article tried to suggest ways to improve satisfaction of their life, as finding the determinants of the disabled through the cross-section research by the Ministry of Health and Welfare. This article used data from the 2011 investigation of actual condition for the Disabled, which is a representative of the disabled in Korea. For statistical analysis, this paper used PASW statistics 18.0 (SPSS Inc, Chicago, USA). Analysis of frequency, descriptive statistic and multiple regressions were conducted. The level of significance was set up as 0.05. As the result, we found that life satisfaction of the disabled was influenced by all factors such as factor in discrimination, socioeconomic factors, disability and health factor. Therefore, we think that the government needs to prepare a systemic method for extending right of the disabled and improving rehabilitation and independent living.