• Journal of the Korean Geotechnical Society
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• v.21 no.10
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• pp.113-122
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• 2005

Application of Limit State Design in geotechnical engineering has become world-widely popular. While LRFD code in the North America presents geotechnical load and resistance factors, the values of resistance factors proposed by these methods are still unstable with limited application. CPT has been widely used for the pile design and various methods have been proposed to estimate the bearing capacity of piles. In this paper, resistance factors for representative pile design methods based on CPT results are evaluated. Field pile load test and CPT results were collected and analyzed in order to obtain necessary statistical data and resistance factors. Resistance factors of the base, shaft, and total capacity are estimated. From fisrt order second moment (FOSM) analysis, resistance factors of $0.30{\sim}0.55$ are estimated for total load capacity.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.343-349
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• 2014

The dental osseointegration implant should be enough to endure occlusion load and it's required to have efficient design and use of implant to disperse the stress into bones properly. Solidworks as a finite element analysis program for modeling and analysis of stress distribution was used for the research. The simple crown model was designed on applying conjoined condition with tightening torque of 20 Ncm of a abutment screw between a cement retained implant abutment and a fixture. A $45^{\circ}$ oblique loading from lingual to buccal side on buccal cusps of crown and performed finite element analysis by 100 N of external load. The results by a analysis for stress distribution of supporting bones of fixture were as below. The von Mises stress was concentrated on the upper side of supporting compact bone regardless of the diameters and lengths of fixture, and the efficiency result of stress reduction was increase of fixture's diameter than it's length. Therefore, it's effective to use wider fixture as possible to the conditions of supporting jaw bone.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.346-359
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• 2016

This study was conducted to find a method of improving social support in college students by analyzing the effects of interpersonal sensitivity and social support on college life satisfaction. To achieve the purpose of the study, questionnaires were distributed to 475 students in six colleges located in Busan Metropolitan City and the collected data were used for analysis. Then, hierarchical regression analysis was conducted using the SPSS statistic program. The major study findings are as follows. First, interpersonal sensitivity negatively influenced social support. Second, interpersonal sensitivity negatively influenced college life satisfaction. Third, social support positively influenced college life satisfaction. Fourth, social support had a mediating effect in the influence of interpersonal sensitivity on college life satisfaction. These study findings demonstrate that there is a need to develop a psychological counseling program for reducing interpersonal sensitivity of college students and improving social support and expand an interpersonal relationship and family relationship improvement program.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.265-273
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• 2017

The purpose of this study was to investigate the relationship among social support, career decision-making self-efficacy, and career decision level in golf majors. For this purpose, a survey was given to a convenience sample of 215 students in universities in Seoul and its metropolitan areas. The data were then analyzed using descriptive statistics, correlations, and multiple regression analysis. The major findings of this study were as follows. First, social support had a significant effect on the career decision-making self-efficacy of golf majors. Second, social support had a significant effect on the career decision level of golf majors. Third, career decision-making self-efficacy had a significant effect on the career decision level of golf majors. The results of this study may be helpful to provide empirical evidence on the roles of social supports and career decision-making self-efficacy needed to decide golf majors' career path.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1118-1125
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• 2009

This study, as basic research which was intended to develope the surface reinforcement method using reinforcement material which is applicable to very soft ground in Korea, was aimed at proposing Bearing Capacity Evaluation method for the surface ground improvement method. To that end, a wide width tensile test using geotextile, geogrid and steel bar (substitute for bamboo) and 21 kinds of the laboratory model tests with the end restraint conditions of the reinforcement that comprises the constrained and partially constrained (3 types) conditions were conducted. According to result of tests, Terzaghi's bearing capacity method is adequate to calculate bearing capacity in non-stiff material(geotextile, geogrid). But, It can't adequate to stiff material(bamboo net). So, New bearing capacity method suggest surface reinforcement method of very soft ground which Terzaghi's bearing capacity method modify for effect of stiffness.

• Journal of the Korean Geotechnical Society
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• v.33 no.6
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• pp.27-36
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• 2017

Gravel compaction pile method has been widely used to improve the soft ground on the land or sea as one of the soft ground improvement technique. The ultimate bearing capacity of the ground reinforced by gravel compaction piles is affected by the soil strength, the replacement ratio of pile, construction conditions, and so on, and various prediction equations have been proposed to predict this. However, the prediction of the ultimate bearing capacity using the existing models has a very large error and variation, and it is not suitable for practical design. In this study, multiple regression analysis was performed using field loading test results to predict the ultimate bearing capacity of ground reinforced by gravel compaction pile, and the most efficient input variables are selected through evaluation of error by leave one out cross validation, and a multiple regression equation for the prediction of ultimate bearing capacity was proposed. In addition, the prediction error was evaluated by applying artificial neural network using the selected input variables, and the results were compared with those of the existing model.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.319-327
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• 2017

In this study, characteristics of seismic behaviors of offshore wind turbine systems using concrete-suction-type supporting structures are investigated. Applying hydrodynamic pressure from the surrounding sea water and interaction forces from the underlying soil to the structural system which is composed of RNA, the tower, and the supporting structure, a governing equation of the system is derived and its earthquake responses are obtained. It can be observed from the analysis results that the responses are significantly influenced by soil-structure interaction because dynamic responses for higher natural vibration modes are increased due to the flexibility of soil. Therefore, the soil-structure interaction must be taken into consideration for accurate assessment of dynamic behaviors of offshore wind turbine systems using concrete-suction-type supporting structures.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.279-287
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• 2016

This study aims to examine the effect of family conflict, social support, and self-esteem on alife satisfaction of the aged. For the study, the subjects(n=296) obtained from the Korea Welfare Panel Survey were analyzed by utilizing the correlation analysis and hierarchical regression analysis. The results founded from data analysis are as follows: First, while family conflict influenced negatively life satisfaction of the aged, social support and self-esteem had a positive effect on it. Second, self-esteem was shown to have the highest effect among other independent variables on life satisfaction of the aged. The results showed that family conflict, social support and self-esteem were the important factors which played the significant role in the change of life satisfaction of the aged. On the basis of the findings, the need and policy support to enhance social support/self-esteem and to weaken family conflict were suggested.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.49.1-49.1
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• 2009

최근 손상된 생체조직의 재생 또는 대체를 위하여 다공성의 지지체(scaffold)를 이용하는 연구가 활발히 이루어져 왔다. 지지체 재료는 조직 재생을 목적으로 하는 경우에는 생분해성 고분자, 생흡수성 세라믹스 또는 이들의 복합재료가 사용되고, 조직 대체를 목적으로 하는 경우에는 금속 또는 세라믹스 재료가 단독으로 사용된다. 현재 경조직 대체를 위한 임플란트 재료로 사용되고 있는 금속재료 중 대부분이 타이타늄 또는 타이타늄 합금이다. 타이타늄은 비강도, 내식성이 우수하며, 생체 내 환경에서 부동태피막 재생 속도가 빠르고, 섬유상 결체조직 형성 두께가 얇아 생체의료용 소재로서 각광을 받고 있다. 다공성 타이타늄은 기존 타이타늄 소재의 장점에 다공체의 구조적인 특성을 부가하여 하중을 받는 골 결손부에 사용될 경우 뼈와의 탄성계수 차이에서 기인하는 응력차폐(stress shielding) 효과를 최소화할 수 있고, 다공체 내부로 골조직 성장을 유도할 수 있어 지지체와 골조직이 일체화되는 골융합 효과의 극대화를 기대할 수 있다. 본 연구에서는 기공 구조를 다양하게 제어할 수 있고, 3차원적 연결 기공구조를 만들 수 있는 적층조형(layer manufacturing) 기술을 이용하여 3차원 다공성 타이타늄 지지체를 제조하였으며, 이에 대한 세포독성, 조골세포 증식능 등 in vitro 생체적합성을 평가하고, Rat model 을 이용한 in vivo 생체적합성을 평가하였다. 또한 지지체의 골조직 재생 유도성의 증대를 위한 생체활성처리 영향도 분석 평가하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4861-4868
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• 2011

This study intends to investigate the health behavior, self-efficacy, behavior pattern and social support among hospital of nurses, to provide the basic data for self-efficacy promoting program and social support promoting program. The self-administered questionnaires were given to 202 nurses employed in hospital during the period from June 10 to June 26, 2011. As a results, the score of level of self-efficacy was statistically significant difference according to educational status, working period, marital state, place of duty, religion, night-duty, distribution of household labor, exercise and stress management. The score of level of social support was statistically significant difference according to place of duty, religion and distribution of household labor, alcohol drinking, smoking, and stress management. But the score of level of behavior pattern was not statistically significant difference according to self-efficacy and social support. In correlation, the score of self-efficacy level correlated positively with social support and not with behavior pattern.