• Journal of the Society of Naval Architects of Korea
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• v.56 no.3
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• pp.263-272
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• 2019

The aim of this study is to develop a rapid calculation technique of the residual strength in order to prevent sequential events under grounding accidents. Very Large Crude-Oil Carrier (VLCC), Suezmax, and Aframax double hull oil tankers carrying large quantities of crude oil were selected for target structures. The rock geometries are chosen from the published regulation by Marine Pollution Treaty (MARPOL) of the International Maritime Organization (IMO). Oceanic rocks as the most frequently encountered obstruction with ships are applied in this work. Damage condition was predicted using ALPS/HULL program based on grounding scenario with selected parameters, i.e. depth of penetration, damage location and tanker type. The results of the scenarios are quantified to form an empirical formula which can evaluate the residual strength. The proposed formula is validated by applying a series of random grounding scenarios.

• Steel and Composite Structures
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• v.47 no.3
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• pp.437-450
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• 2023

A half open cross section built-up column, namely cold-formed thin-walled steel built-up column with 12-limbsection (CTSBC-12) is put forward. To deeply reveal the mechanical behaviors of CTSBC-12 under axial compression and put forward its calculation formula of axial bearing capacity, based on the previous axial compression experimental research, the finite element analysis (FEA) is conducted on 9 CTSBC-12 specimens, and then the variable parameter analysis is carried out. The results show the FEA is in good agreement with the experimental research, the ultimate bearing capacity error is within 10%. When the slenderness ratio is more than 96.54, the ultimate bearing capacity of CTSBC-12 decreases rapidly, and the failure mode changes from local buckling to global buckling. With the local buckling failure mode unchanged, the ultimate bearing capacity decreases gradually as the ratio of web height to thickness increases. Three methods are used for calculating the ultimate bearing capacity, the direct strength method of AISI S100-2007 gives result of ultimate axial load which is closest to the test and FEA results. But for simplicity and practicality, a simplified axial bearing capacity formula is proposed, which has better calculation accuracy with the slenderness ratio changing from 30 to 100.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.06a
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• pp.31-42
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• 2002

The Design criteria are different from one another due to the different engineering properties of rock in the every nation. Most of the test results of the rock-socketed piers were loaded two times of the design load capacities because they would be used in the foundation of the bridge or the building. So we have much difficulties in study of the load capacities of the rock-socketed piers by the test result in Korea. When we design the rock-socket piers, every designer uses the different formula, and makes different results. Recently the demand of the large bridges and the huge buildings has been increased. The adequate design criterion of the rock-socketed pier is urgently needed to design them reasonable. In this paper we analyzed the various design criteria and proposed the adequate design criterion which is based on the test results of the rock-socked piers in Korea.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.256-257
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• 2019

Recently, the fire risk of architectural structures is increasing due to the super high - rise and super - size of the buildings. Therefore, the direction of fire safety design tends to change from the existing design to the performance - based design. In particular, domestic fire safety policies are divided into building law and fire fighting law. In case of fire fighting law, performance design is already carried out. Therefore, this study summarizes the prediction formula for fire characteristics among the structural fireproofing design field as shown in Fig. 1 according to this situation, and compares it with the standard method of each country in particular.

• Magazine of the Korea Concrete Institute
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• v.6 no.1
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• pp.111-119
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• 1994

The strength of vertical joints of precast concrete large panel structures depends on the many factors, such as the bond strength of grout concrete (or mortar), the interlocking of the shear keys, the dowel action of horizontal bars. Many experimental studies have been conducted to in vestigate the shear strength of the vertical joints. In domestic, a few design formulas to predict shear strength of the vertical joint were proposed by some investigators, but formulas were based on limited experimental results. The objective of this paper is to propose a suitable formula for the shear strength of vertical joints with 94 vertical joints experimental data using the modified Mohr-Coulomb's 4ield theory and regression analysis. From the comparison of the proposed formula with others, it is shown that the proposed formula can be used economically for the design of vertical joints.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.1
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• pp.72-85
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• 2001

A study for the structural strength evaluation on the doubler plate subjected to the biaxial in-plane compression has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. A1so, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et a1. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.4
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• pp.92-105
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• 2000

A study for the structural strength evaluation on the slender doubler plate has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate subjected to the longitudinal in-plane compression, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. Also, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et al. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• Fashion & Textile Research Journal
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• v.21 no.2
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• pp.189-202
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• 2019

This study develops a bodice pattern for high school girls aged 17 to 19 that use virtual garment simulation. The study developed a bodice pattern based on the fit evaluation result for two selected bodice patterns. The basic formula of the design method based on the result of 3 times of fit evaluation is as follows: waist back $length=stature/8{\times}1.85cm$, waist front length=waist back length+bust/40+0.7cm, front bust girth=bust/2+4cm, back bust girth=Chest/2+3cm, armscye depth=Chest/4+0.5cm, back interscye length=bishoulder length -1.2cm, front interscye length=back interscye length -1.2cm, front neck width=back neck width -0.3cm. The developed bodice pattern used Bishoulder Length as a criteria for the calculation formula of back interscye length, and back interscye length as a criteria for the calculation formula of front interscye length. The fit evaluation showed the relevance of the bishoulder length, front interscye length, and back interscye length based on a comparison of the calculated figure. A bodice pattern with great body suitability and fitness to high school girls was developed through 3D virtual garment simulation that calculated the application of body proportion to width. This study only analyzed the evaluation result of a virtual model only in a representative form; however, a pattern study is also proposed to compare and analyze the design methods of patterns by body type.

• Journal of the Korean Society for Nondestructive Testing
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• v.5 no.1
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• pp.34-47
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• 1985

The developing country, KOREA where does not possess the natural resources for traditional energy such as oil and gas, so. The nuclear energy is the most single reliable source available for closing the energy gap. For these reason, It is inavoidable to construct the nuclear power plant and to develop technology related nuclear energy. The rate of operation in large nuclear power facilities depends upon the performance of work system through design and construction, and also the applied technology. Especially, it is the most important element that safety and reliability in operation of nuclear power plant. In view of this aspects, Nuclear power plant is performed severe examinations during preservice and inservice inspection. This study provide an automation of analysis for volumetric examination which is required to nuclear power plant components. It is composed as follows: I. Introduction II. Inservice Inspection of Nuclear Power Plant ${\ast}$ General Requirement. ${\ast}$ Principle and Methods of Ultrasonic Test. ${\ast}$ Study of Flaw Evaluation and Design of Classifying Formula for Flaws. III. Design of Automation for Flaw Evaluation. IV. An Example V. Conclusion In this theory, It is classifying the flaws, the formula of classifying flaws and the design of automation that is the main important point. As motioned the above, Owing to such as automatic design, more time could be allocated to practical test than that of evaluation of defects, Protecting against subjective bias tester by himself and miscalculation by dint of various process of computation. For the more, adopting this method would be used to more retaining for many test data and comparative evaluating during successive inspection intervals. Inspite of limitation for testing method and required application to test components, it provide useful application to flow evaluation for volumetric examination. Owing to the characteristics of nuclear power plant that is highly skill intensive industry and has huze system, the more notice should be concentrated as follows. Establishing rational operation plan, developing various technology, and making the newly designed system for undeveloped sector.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.208-216
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• 2019

This study investigated design factors and removal efficiencies of a sheet flow channel as natural type water improvement techniques in the stream. The channel was designed considering the design factors, then constructed and monitored in the test bed of the Osan stream's floodplain. Water lever, velocity, discharge, T-P, T-N, and NO₃-N were monitored and the removal efficiencies and design formula were suggested. Overall efficiencies of T-P, T-N, and NO₃-N range 10 - 20%, and they show consistent relations with residence times. Minimum velocity requirement is also suggested from the relation of algae conditions and velocities. Relation formula of residence time and removal efficiency will be applicable in the design and operation process of a sheet flow channel.