• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.478-485
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• 2018

Aids to Navigation (AtoN) is one of the marine traffic safety facilities that promotes the safety of maritime traffic and enhance ship's operational efficiency. However, functional failure of AtoN due to ship's collision or bad weather conditions leads to inconvenience or navigational risk to various users such as the ship operators. For insstance, the largest container port in Korea, Busan Port has experienced a total of 400 AtoN accidents in the past 12 years (2006-2017).Therefore, an average of 20.6 days of recovery time is required, which increases the maritime safety anxiety for AtoN users. is the objective of this study was to present the quantitative support of the users for the prevention of AtoN accidents and the improvement of the feasibility of implementing more efficient management in Korea. A survey was conducted on the users of Busan port areas to investigate general perception of AtoN in general and the accidents that have happened, and to estimate the economic value of navigational risk reduction by implementing effective AtoN management measure. Using the representative non-market valuation method for environmental or public goods known as contingent valuation method (CVM), the economic value granted to users for the AtoN services in Busan port was estimated to at least 16 billion won. Therefore, these finding could be used by AtoN managers and/or policy makers as a valuable data to identify the users' need of various AtoN services including Busan Port and to establish and implement more efficient management plan.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.391-400
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• 2019

In the case of fire, a structure loses its original stiffness due to the temperature rise, and the load bearing capacity decreases. The loss of structural strength increases with increasing fire time of the structure. To prevent the collapse of buildings, it is very important to understand whether or not the members are damaged. On the other hand, there is insufficient data to be a guideline for diagnosing and evaluating the residual strength of the members in Korea. Therefore, this study examined the resistance performance by Finite-Element-Analysis of composite beams, which are composite structures among structural members. Composite beam modeling was carried out based on the model used in the Electrical Penetration Room (EPR) in cooperation with KEPCO. The heat transfer analysis and structural analysis of the critical phase were performed using ANSYS, a finite element analysis program. ANSYS was used to perform heat transfer analysis and structural analysis at the static analysis. To analyze the residual performance, the temperature distribution of the composite beam and the maximum displacement result of the heat-affected structure analysis were derived and the experimental data and the structural analysis result data were compared and analyzed.

• Korean Journal of Family Social Work
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• no.57
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• pp.125-157
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• 2017

The purpose of this study was to analyse effects of public support for single-parent family for adolescent single-parent who experienced social exclusion and social network. This study utilized a part of National Youth Policy Institute's 'Research on the Actual Condition of the Adolescent Pregnancy, Birth and Rearing Children'. Participants of the study were 262 adolescent single-parents at the age of 24 and below. In order to understand the effect, this study verified the moderating effect of public support for single-parent family in the context of social exclusion and social network on parental attitude and behavior(parenting efficacy, parenting stress, negative parenting behavior). Results of this study are as follows; First, Nearly half of adolescent single-parent has economic hardship in original family and most they lived with preschool children on unemployed state that the average monthly income of them was about 600,000 won. It means that their financial independence difficult. Second, family support was only significant factor for parenting efficacy and positive relationship with family and acquaintances was major influence factor for causing positive parental behavior of adolescent single-parent. As a result, social network was verified more important factor than social exclusion on parental attitude and behavior. Lastly, public support for single-parent family was confirmed as social mitigation mechanism that has the moderating effect of social exclusion and social network on parental attitude and behavior.

• 한국노년학
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• v.32 no.4
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• pp.993-1011
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• 2012

The purpose of this study is to investigate the factors associated with the incidence and the transition of disability among Korean older adults. Samples consist of 1,454(42.7%) men and 2,032(58.3%) women aged 65 and over who participated in the 1st and 2nd wave of the Korea Longitudinal Study of Aging: KLOSA. To estimate the level of disability, ADL and IADL disability indexes are used. As the results, major risk factors for ADL/IADL disability incidence include injury, vision problem, cognitive function, depression, health behavior, socioeconomic characteristics and age. Among the normal older adults, the odds ratio of having dementia symptoms at 2nd wave(2008) are 2.0 times greater for the older adults who have less cognitive function than those who don't have at 1st wave(2006). Among the older adults with chronic diseases, the odds ratio of having disability at 2nd wave are 1.8 times greater for the older persons who have depression than those who don't have at 1st wave. Secondly, concerning the predictors affecting the disability transition among the disabled older adults at 1st wave, the likelihood of remaining at the same level or deteriorating the level of IADL disability, as compared with improving the level, is associated with having less instrumental support or being older. These results indicate that it is necessary to prefer multilevel intervention in order not only to prevent the incidence of disability, but also to prolong the deterioration of disability in the older adults.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.594-601
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• 2019

A true MSEW abutment is an abutment type that directly supports the load of a superstructure. Metal strips, which are in-extensile reinforcements, should be used to minimize abutment deformation. A study to derive the application conditions of a True MSEW abutment was carried out by Zevogolis(2007). As a result, the pullout factor of safety of the uppermost reinforcement was estimated to be the smallest. Therefore, the pullout factor of safety of the uppermost reinforcement is the most important design factor. Parameter analysis was conducted with the abutment length, abutment heel, and abutment height as variables. The pullout factor of safety increased with increasing abutment length and abutment heel length. This is because the contact area increases and the superstructure is dispersed as the abutment length and abutment heel length increase. The pullout factor of safety converges at an abutment length of 1.2m and an abutment heel length of 0.9m. This is because the effective length of the reinforcement is reduced due to the increase in contact area. On the other hand, the extension of the superstructure will increase if the abutment length and abutment heel length are increased excessively. In addition, earth-volume is increased if the abutment height increases excessively. This acts as an upper load on the MSE wall. Therefore, it needs to be examined carefully.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.1-12
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• 2019

The purpose of this study is to enhance the seismic performance of exposed column-base plate weak-axis connections for small-sized steel buildings. According to the site inspection for the small-sized building construction, the arbitrary connection details in steel buildings have been applied at the job site, which is considered to be insufficient to guarantee structural safety and stability considering the increased seismic risk in Korea. Therefore, a series of test programs had been done to develop enhanced connection details in order to ensue the adequate seismic stability and safety of small-sized steel buildings. From the test results, It was found that the exposed column-base plate weak-axis connections commonly used in Korea shows very poor seismic behavior due to the "Rocking" phenomena caused by the residual plastic deformation of anchor bolts between anchor plate and concrete. A series of hysteretic tests for finding that solution were conducted to reduce the "Rocking" phenomena of the column-base plate connections, and local buckling of webs in H-column. Finally the enhanced stable seismic behavior was obtained by reinforcing at least 8 anchor bolts with good bonding strength and stiffeners to the webs in H-column.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.84-95
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• 2019

This paper reports the process of seismic fragility analysis for the rahman-type continuous bridge system. The target structure was the five span highway bridge with maximum pier hight of 72m. OpenSees software was used for the nonlinear time history analysis. In this study, 50 ground motions are considered for nonlinear time history analysis. For each ground motion, PGA was scaled from 0.1g to 2.0g with intervals of 0.1g in order to consider a wide range of the seismic intensity measure. In addition, yield displacement and ultimate displacement of each pier were calculated through section analysis. Based on the result of non linear time history analysis and section analysis, damage condition of target bridge was classified according to the definition of damage condition proposed by Barbat et al. As a result, it was predicted that Extensive Damage occurred at P1 when 0.731 g earthquake occurred in the longitudinal direction. Based on the seismic fragility analysis results, it is found that the probability of occurrence of Extensive Damage in the 4,800 - year period earthquake was about 4.2%. Therefore the target bridge has enough safety for earthquake.

• Management & Information Systems Review
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• v.38 no.1
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• pp.155-168
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• 2019

The objective of our study is to examine the Earnings Quality of Win-Win Growth Corporate. The level of Win-Win Growth Corporate is measured by Win-Win Index of korea commission for corporate partnership. Earnings Quality is proxied by Accounting Conservatism that is measured by the method of Givoly and Hayn(2000). The samples of this study selected from listed corporate, consist of 3,608 observations can be collected from 2011 to 2017 at TS-2000. The result of this study can be summerized in the following. the Win-Win Growth has a significant positive relevance on Accounting Conservatism is the proxy of internal Earnings Quality. This means that Win-Win Growth corporate has a higher the Earnings Quality relatively. These results were supported by additional analysis that used the sample that is made up the Win-Win Growth Corporate completely. According to our study, we can expect that the Earnings Quality of Win-Win Growth corporate is true as steel. But this study have some limitation. Especially we can't explain the reason why the Win-Win Growth has a significant positive relevance on Earnings Quality. And, despite additional analysis, there are the limitation of controlling for endogeneity. We hope that our paper can help investor making a economic decision on investment and officials making a effective policy on the Win-Win Growth.

• Journal of the Korean Geotechnical Society
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• v.35 no.7
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• pp.15-27
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• 2019

The purpose of this study is to investigate the mechanism about damages occurring at quay wall and backfill in Youngilman Port during Pohang earthquake (M5.4) on November 15, 2017. In the field investigation, the horizontal displacement of the caisson occurred between 5 cm and 15 cm, and the settlement at backfill occurred higher than 10 cm. 2D-effective Stress Analysis was performed to clarify the mechanism for the damage. The input earthquake motion used acceleration ($3.25m/s^2$) measured at bedrock of Pohang habor. Based on a numerical analysis, it was found that the effective stress decreased due to the increase of excess pore pressure in the backfill ground and the horizontal displacement of the caisson occurred by about 14 cm, and the settlement occurred by about 3 cm. In backfill, the settlements occurred between 6 cm and 9 cm. This is similar to field investigation results. Also, it was found that the backfill soil was close to the Mohr-Coulomb failure line due to the cyclic loading from the effective stress path and the stress-strain behavior. It may be related to decreasing of bearing capacity induced by the reduction of effective stress caused by the increase of the excess pore water pressure.

• The Journal of the Korea Contents Association
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• v.21 no.10
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• pp.368-377
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• 2021

This study analyzed the determinants of capital structure based on the financial statements of agricultural corporations disclosed on the DART(data analysis, retrieval and transfer system) of the Financial Supervisory Service since 2011, when the Korea international financial reporting standards (K-IFRS) was introduced. There have been many empirical studies on the capital structure so far, but there are no studies targeting agricultural corporations. The sample period of agricultural corporations was from 2015 to 2019, with the debt ratio as the dependent variable, and among the variables suggested as meaningful in existing empirical studies, ROA(profitability), SIZE(corporate size), LIQ(liquidity), TA(tangible asset ratio), FA(fixed long-term suitability ratio), and GROWTH(growth potential) were selected as independent variables and panel data analysis was performed. As a result of the analysis, it was found that the debt ratio decreased as the ROA and SIZE of agricultural corporations increased. This can be interpreted as supporting the pecking order theory rather than the static trade-off theory in the relationship between the ROA and SIZE of Korean agricultural corporations with the capital structure. In addition, it was found that the debt ratio increased as the FA increased. These results suggest that Korean agricultural corporations need to establish a financing policy in consideration of ROA, SIZE, and FA.