• Journal of Welding and Joining
• /
• v.28 no.4
• /
• pp.26-32
• /
• 2010

The purpose of this study is to evaluate the residual stresses at the multi-pass FCA weldment using the finite element analysis (FEA). In order to do it, an H-type specimen was selected as a test specimen. The variable used was in-plane restraint intensity. The temperature distribution at the multi-pass FCA butt weldment was evaluated in accordance with the relevant guidance recommended by the KWJS. The effective conductivity for the weld metal corresponding to each welding pass was introduced to control the maximum temperature below the vaporization temperature of weld metal. The heat flux caused by welding arc was assumed to be applied to the weld metal corresponding to welding pass. With heat transfer analysis results, the distribution of transverse residual stresses was evaluated using the thermo-mechanical analysis and compared with the measured results by XRD and uniaxial strain gage. In thermo-mechanical analysis, the plastic strain resetting at the temperature above melting temperature of $1450^{\circ}C$ was considered and the weld metal and base metal was assumed to be bilinear kinematics hardening continuum. According to the comparison between FEA and experiment, transverse residual stresses at the multi-pass FCA butt weldment obtained by FEA had a good agreement with the measured results, regardless of in-plane rigidity. Based on the results, it was concluded that thermo-mechanical FE analysis based on temperature distribution calculated in accordance with the KWJS’s guidance could be used as a tool to predict the distribution of residual stress of the multi-pass FCA butt weldment.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.7
• /
• pp.3562-3569
• /
• 2013

The performance of concrete structure decreases with change in time and the external environment. In order to reinforce the structure, the research about new material development and application of newly developed materials are widely conducted. In the case of composite FRP, it received good attention in the academia due to its high intensity-weight ratio, excellent corrosion resistency as well as good workability. When applying at the construction field, however, the utilization of FRP did not increase as much due to lack of reliability and design standard. Current study investigated the material characteristics during the temperature change at high temperature and the structural behavior from restraint effect for GFRP reinforcing materials. Two experimental variables were set in this study: GFRP reinforcements due to tensile properties of temperature and restraint compression effects. Three concrete specimen were selected for each set temperatures. For this reason, as a variable to experiment with the effects confined compression concrete members value and tensile properties with temperature reinforcement GFRP, experiment produced three pieces each for each set temperature, the concrete specimen, which is confined in the GFRP was selected each I did. For the temperature change during the experiment, the concrete specimen were mounted in order to expose to experimental high temperature for certain period of time. For compression performance evaluation, reinforcement effect from horizontal constraint of the fiber were measured using an Universal Material Testing Machine (UTM). Finally, this study revealed that the binding characteristics of GFRP materials from temperature change decreased. Also, this study showed that the maximum compression intensity decreased as the temperature increased up to $150^{\circ}C$ in the constraints ability of the GFRP reinforcements during the horizontal constraint of concrete.

• Journal of the Korean Geographical Society
• /
• v.51 no.1
• /
• pp.143-166
• /
• 2016

This study aims to consider spiritual therapeutic landscapes thought the case of catholic sacred places in Korea. The catholic sacred places, which have been a series of persecution, are distributed in 300 all over the country and can be divided into a formational type, a selective type, and a participatory type. In the formational type, the catholic sculptures are scattered here and there; but it seems that there are limits somewhat to feel the emotional stability and the experience of caring by God. Because the formational type is deserted or is built up in unnoticeable urban areas. The religious factors, for example, museums, special pray, Station of the Cross, Rosary way, statues of the Virgin Mary, catholic sculptures, etc. in the selective type are placed in the corners of the catholic sacred places to provide the opportunity of holy experience to pilgrims. But the level and the intensity of healing depends on the matter as to how much pilgrims experience religious factors voluntarily. Lastly, the participatory type means the experience of various religious factors following scheduled programs. The experience is for the group of pilgrims, not a person; and the human relationship via the religious experience spiritualizes the network of interest towards other participants. Furthermore, the spiritualized open mind towards other people becomes the power that can arrive at the emotional stability, the relief of stress, and the in-depth and authentic healing. Ultimately, the spiritual healing through religious factors is to realize human finitude and dedicate one's own self to God; in addition, the spiritual therapeutic landscapes are the place that can carry out such a spiritual ritual without any restraint.

• Economic and Environmental Geology
• /
• v.41 no.3
• /
• pp.315-326
• /
• 2008

Recently, the occurrence and intensity of Asian Dust have dramatically increased in Korean peninsula, resulting in severe damages to the domestic social and economic field. The most useful way to prevent the damage of Asian Dust is the restraint of the occurrence of Asian Dust itself. However, Asian dust is the one of the natural phenomena, thus there is a basic limit to manage the Asian Dust. Though it is impossible to restrain the occurrence of Asian Dust in short time at present, it is a urgent matter to minimize the damage of Asian Dust. It is necessary to construct the basic data for understanding the harmfulness of Asian Dust, and to elucidate the source area of Asian Dust in connection with the maleficence of itself. In this study, the source area of Asian Dust in spring, 2007, is investigated using the Sr-Nd isotopic ratios which is the most common method to trace the source of geological materials. The relationships of Sr-Nd isotope ratios indicate that Asian Dust was originated from Central Loess Plateau and/or Ordos desert in spring, 2007.