• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.4
• /
• pp.598-605
• /
• 2010

The structural design of oil tankers and bulk carriers should be performed based on the Common Structural Rules(CSR) which were recently established by the International Association Classification Societies(IACS). At first, in the structural design viewpoint, the scantling and hullweight based on the CSR should be compared with those of existing rules, and then a minimum weight/cost design should be performed by considering the variation of the number of web and the material property. In this study, the optimum web space and material property will be proposed by performing a minimum weight/cost design of a large oil tanker, and the results will be compared with those of existing ship. The longitudinal members are determined by SeaTrust-Holdan developed by the Korean Register of Shipping(KR), and the transverse members are determined by NASTRAN and PULS.

• The Research Journal of the Costume Culture
• /
• v.24 no.1
• /
• pp.107-113
• /
• 2016

The purpose of this study was to examine new-silver women's fiber and material property preferences and purchasing behaviors. The survey subjects were 115 new-silver women ranging in age from 50 to 60 years old. This study utilized a questionnaire as a measurement tool. The results of this study were as follows: First, the home ownership rate of the participants in this was 81.4%, and 54.9% of them had a bachelor's degree or higher. Therefore, they turned out to be a new silver generation with higher education and stable income and assets. Second, regarding their purchasing behaviors, it was shown that they purchased the largest amount of clothing for themselves and their spouses, children, and grandchildren at the change of seasons. Third, with regard to their average spending on clothing, when they purchased clothing for themselves, it was shown that they purchased clothing at the price of KRW 500,000 or above for themselves but not for their family members. Fourth, their favorite type of fiber was synthetic fiber, and their favorite material property was heaviness, followed by roughness, stiffness, bulkiness, and glossiness. Moreover, with regard to their favorite functional textile, it was shown that the highest percentage of them preferred vitamin textiles, followed by ocher and scented textiles.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.1
• /
• pp.36-44
• /
• 2005

Nowadays, various kind of rubber-like materials are used in industry. These are usually installed in automobiles, trains, etc. They work as dampers or important parts in the system, and the applications for rubber-like materials are increasing. In the past days, rubber engineers and designers predicted rubber material behaviors by the analytic method for limited problems. With the progress of digital computers, Finite Element Methods is widely used for analyzing the rubber-like materials. The popular methods predicting rubber material property are curve fitting and least square method, but there are some problems such as low precision and tedious solving process. Here, we introduce a method estimating rubber material property by successive zooming genetic algorithm(SZGA). The proposed algorithm offers more precise rubber property. To demonstrate the effectiveness of the proposed algorithm, we compared this method with Haines & Wilson's method, MARC, ABAQUS.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.5
• /
• pp.103-111
• /
• 2008

This study proposes a technique to estimate the material property of a paper by using an experimental methods and commercial CAE software. Under gravitation, if one side of the paper is attached to the ground, the opposite side of paper is largely deformed, and vibrates freely. Since the paper has an orthotropic characteristic due to its treatment, the deformations in two orthogonal directions of the dry paper are different. An experimental method to measure the static deformation of the paper introduces this phenomenon. And dynamic behavior, frequency of free vibration is measured. And then. virtual prototypes that can represent the static and dynamic behavior are modeled by using the commercial CAE software $RecurDyn^{MT}$/MTT3D, which has been widely used by the printer makers. While comparing the deformation and frequency from the experiment and simulation, a design optimization technique in the commercial CAE software of R-INOPL, $RecurDyn^{TM}$/AutoDesign is used to estimate the material property such as Young's modulus, shear modulus and density of the paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.319-322
• /
• 2004

In this paper, we studied on the thermal conductivity and a mechanical property of the elastic epoxy. According to industrial development, insulation materials have various properties. They are solid, liquid, gas state, there are various type. Epoxy, a kind of insulation material, demand of not only high hardness but also elastic property. When the electric current flows into the conductor and the place where the heat occurs, this heat becomes the cause which shortens the life of the electrical appliance. Therefore, for the heat occurred transmit quickly, thermal conductivity of the insulation material is highly demanded. We studied on the thermal conductivity of elastic epoxy on the high voltage. In this result, thermal conductivity confirmed that it followed thermal property of mixed epoxy and addictives. Hardness is decreased when addictives increased.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.2 no.2
• /
• pp.93-100
• /
• 2006

Building materials are trending toward environmental materials nowadays and the market share of those is growing. So those researches and developments for environmental property are proceeding now. The main properties of environmental products are far infrared emission, negative ion emission, electro magnetic wave shielding, and anti fungus, these products are used with shape of mortar, and spray on the finish material. But There are not much researches for the concrete, main material in construction field, with those functional properties. So in this research we evaluated slump, compressive strength and air content as basic properties for concrete using functional materials of sericite, wood pattern sand stone, carbon black and nanometric silver solution and functional properties like far infrared emission, negative ion emission, electro magnetic wave shielding, and anti fungus. The results were as follows. The most useful material in the functional materials was carbon black. Sericite and nanometric silver solution had a little effect on functional property, so it was difficult to apply to concrete, and wood pattern sand stone had a high functional property but low compressive strength, can be applied to a factory product. Anti fungus of the concrete using nanometric silver solution was not clear but if those specimens were aged in $CO_2$ gas for a long time it might apparent.

• Journal of Welding and Joining
• /
• v.28 no.1
• /
• pp.60-65
• /
• 2010

This paper is concerned with effects of Al, Mn and Si contents on spatter, fume, microstructure and mechanical property with 490MPa Grade Flux Core Wire(FCW). Ten kinds of FCW were fabricated by varying Mn, Si and Al contents and each FCW was weld for check the amount of spatter and fume generations, microstructures and mechanical property. Amount of spatter and fume generations was decreased with the increasing Si contents and decreasing by Al contents in FCW. And, their microstructure of weld metal were changed by Mn, Al and Si contents in FCW. With increasing of Al and Si, acicular ferrite was fine and volume fraction of acicula ferrite was increased. Thereby leading to improvement of Charpy impact property and strength.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.535-536
• /
• 2006

Researches about micro technology travel lively in these days. Such many researches are concentrated in the field of materials and a process field. But properties of micro materials should be known to give results of research developed into still more. In these various material properties, reliability data such as mechanical, optical, thermal property, etc is the basic property. In this paper, it is measured that is material properties of main BLU(Back Light Unit) components in LCD(Liquid Crystal Display). The pattern shape of prism sheet, diffuser film and reflective plate are measured by variable 3D scanning equipments. It is researched which is the method to measure an optimal 3D pattern shape in each components.

• Journal of Ocean Engineering and Technology
• /
• v.34 no.6
• /
• pp.481-488
• /
• 2020

Composite materialsuch as glass-fiber reinforced plastic and carbon-fiber reinforced plastic (CFRP) shows anisotropic property and have been widely used for structural members and outfitings of ships. The structural safety of composite structures has been generally evaluated via finite element analysis. This paper presents a technique for updating the finite element model of anisotropic beams or plates via natural frequencies. The finite element model updates involved a compensation process of anisotropic material properties, such as the elastic and shear moduli of orthotropic structural members. The technique adopted was based on a discrete genetic algorithm, which is an optimization technique. The cost function was adopted to assess the optimization problem, which consisted of the calculated and referenced low-order natural frequencies for the target structure. The optimization process was implemented with MATLAB, which includes the finite element updates and the corresponding natural frequency calculations with MSC/NASTRAN. Material properties of a virtual cantilevered orthotropic beam were estimated to verify the presented method and the results obtained were compared with the reference values. Furthermore, the technique was applied to a cantilevered CFRP beam to successfully estimate the unknown material properties.

• The Journal of the Korea Contents Association
• /
• v.3 no.2
• /
• pp.87-95
• /
• 2003

Prompt and efficient information collection on each research area is emerging as the key factor of national technology competitiveness in industrialized society. Accordingly, constructing a variety of specialized DBs as the tool for supporting R&D activities and providing appropriate information are essential task to be solved in promoting R&D productivity. On this study, We have developed ceramics material property DB to support and facilitate R&D activities of industry, academia and research institutes. The ceramic property DB which was regarded as the most important DB surveyed from korean done for scientists and researchers was selected. To develop this DB, us have designed DB customized for domestic users after analyzing items and structures of ceramic material property information. We hope that R&D researchers can save time and cost in acquiring property information and the R&D productivity will be improved by utilizing our research result.