• Journal of the Society of Naval Architects of Korea
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• v.54 no.2
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• pp.151-160
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• 2017

Growing demand and rapid development of the synthetic fiber rope in mooring system have taken place since it has been used in deep water platform lately. Unlike a chain mooring, synthetic fiber rope composed of lightweight materials such as Polyester(polyethylene terephthalate), HMPE(high modulus polyethylene) and Aramid(aromatic polyamide). Non-linear stiffness and another failure mode are distinct characteristics of synthetic fiber rope when compared to mooring chain. When these ropes are exposed to environmental load for a long time, the length of rope will be increased permanently. This is called 'the creep phenomenon'. Due to the phenomenon, The initial characteristics of mooring systems would be changed because the length and stiffness of the rope have been changed as time goes on. The changed characteristics of fiber rope cause different mooring tension and vessel offset compared to the initial design condition. Commercial mooring analysis software that widely used in industries is unable to take into account this phenomenon automatically. Even though the American Petroleum Institute (API) or other classification rules present some standard or criteria with respect to length and stiffness of a mooring line, simulation guide considers the mechanical properties that is not mentioned in such rules. In this paper, the effect of creep phenomenon in the fiber rope mooring system under specific environment condition is investigated. Desiged mooring system for a Mobile Offshore Drilling Unit(MODU) with HMPE rope which has the highest creep is analyzed in a time domain in order to investigate the effects creep phenomenon to vessel offset and mooring tension. We have developed a new procedure to an analysis of mooring system reflecting the creep phenomenon and it is validated through a time domain simulation using non-linear mooring analysis software, OrcaFlex. The result shows that the creep phenomenon should be considered in analysis procedure because it affects the length and stiffness of synthetic fiber rope in case of high water temperature and permanent mooring system.

• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.99-106
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• 2001

The main objective of this study is to develop a continuity of double tee slab with two modified dap-ends to solve the problems of excessive moment, slab depth, deflection, and joint cracking in the original simply supported double tee slab systems. The modified joint is produced in a combination with two slabs with modified dap and one rectangular beam. The modified joint can be justified as following different merits. The span capacity for a design load is increased, while the deflection of the slab is decreased due to the decrease of positive moment at the center span of the slab. The joint cracking between slab and beam, which occur frequently in the original slab systems of double tee will be reduced. No more additional form work is needed to cast topping concrete for continuity. Three point loading tests are performed on the specimens with a variable of an amount of main longitudinal reinforcement to evaluate flexural and shear behavior. Following conclusions are obtained from the experimental investigation. The continuity of double tee slab effectively is provided by placing longitudinal steel reinforcement in the topping concrete over the connection, and generally leads to an increase in span capacity of double tee slabs with reduced deflection. It is more effective to control the initial cracking at the connection than that of some simply supported double tee slab systems.

• 대한공업교육학회지
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• v.40 no.2
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• pp.92-110
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• 2015

The purpose of this study is to provide necessary information to understand characteristics of vocational high school students and to enhance academic engagement through social support of teachers, leading to help research of teaching and learning strategy. A survey was conducted on 990 engineering major students attending 11 vocational high schools in Seoul metropolitan, Chungcheong, Jeolla, Kyeongsang and Kangwon regions. A questionnaire consists of measurement tools for the academic engagement (21 questions) and the social support of teachers (25 questions). The findings of this study are as follows: First, it is found that the level of students' academic engagement was high. But it appears that the students showed low engagement of emotion compared with that of behavior and cognition. There was no level difference according to gender, but there was a considerable difference according to a school year. The first year students' level of engagement was higher than the second and the third year students' in terms of cognition and emotion. Second, it shows that the level of the teachers' social support was normal, which was in the order of appraisal support, instrumental support, informational support, and emotional support. Especially, the level of appraisal support and instrumental support was most. Third, there were correlation and explanation between students' academic engagement and teachers' social support. Moreover, the result that teachers' emotional support has high correlation and explanation in qualitative terms of academic engagement support the importance. Therefore, it is concluded that the social support of teachers can make an positive influence on improving the academic engagement of students and provide students with adaptability and satisfaction with their school life, which may give students a positive effect in emotional development, self-formation, and complement.

• KIPS Transactions on Computer and Communication Systems
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• v.1 no.2
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• pp.79-86
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• 2012

An economic ship routing means to sail a ship with a goal of minimizing the fuel consumption by utilizing weather forecast information, and various such systems have been recently studied. For a successful economic ship routing system, an efficient algorithm is needed to search an optimal geographical path, and most of the previous systems were approaching to that problem through a minimal static-cost path search algorithm based on the Dijkstra algorithm. To apply that kind of search algorithm, the cost of every edge assigned with the estimated fuel consumption should be constant. However, that assumption is not practical at all considering that the actual fuel consumption is determined by the weather condition when the ship will pass the edge. To overcome such a limitation, we propose a new optimal ship routing system based on a minimal dynamic-cost path search algorithm by properly modifying the Dijkstra algorithm. In addition, we propose a method which efficiently reduces the search space by using the $A^*$ algorithm to decrease the running time. We compared our system with the shortest path-based sailing method over ten testing routes and observed that the former reduced the estimated fuel consumption than the latter by 2.36% on average and the maximum 4.82% with little difference of estimated time of arrival.

• Journal of the Society of Disaster Information
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• v.11 no.3
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• pp.365-375
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• 2015

This study is significant in the sense that it minimize the negative effect of workplace bullying, ultimately it maximize organizational performance and keep private security guards physical and mental health. We tested the hypothesis that workplace bullying negatively impacts private security guard's office attitude, but there will be significant difference in influence with their level of self-esteem scale. First of all, as the result of the correlation analysis of each of variables, a positive correlation was found between self-esteem and job satisfaction but negative correlation between self-esteem they have, the more job satisfaction they get, the lower turnover intention they have. Second, we tried to find out how self-esteem affect them on their job satisfaction. Using regression analysis, we can see that job satisfaction is affected by age, workplace bullying, relational aggression and self-esteem. For example, job satisfaction is increased as they get old and self-esteem is improved, on the other hand, workplace bullying and relational aggression is decreased. Third, to find out how self-esteem affects their turnover intention, we did regression analysis. The result shows that turnover intention is affected by age, working period, workplace bulling, relational aggression and self-esteem. For example, turnover intention if higher as working period, workplace bullying, relational aggression is increased while age and self-esteem is decreased.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.205-215
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• 2008

As static traffic assignment has reached its limitation with ITS policy applications and due to the increase of interest in studies of ITS policies since the late 1980's, dynamic traffic assignment has been considered a tool to overcome such limitations. This study used the Dynameq program, which simulates route choice behavior by macroscopic modeling and dynamic network loading and traffic flow by microscopic modeling in consideration of the feasibility of the analysis of practical traffic policy. The essence of this study is to evaluate the feasibility for analysis in practical transportation policy of using the dynamic traffic assignment technique. The study involves the verification of the values estimated from the dynamic traffic assignment with South Korea's expressway network and dynamic O/D data by comparing results with observed link traffic volumes. This study used dynamic O/D data between each toll booth, which can be accurately obtained from the highway Toll Collection System. Then, as an example of its application, exclusive bus-lane policies were analyzed with the dynamic traffic assignment model while considering hourly variations.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.7
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• pp.778-787
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• 1999

이제까지 대부분의 다중 에이전트 시스템에서는 에이전트 사회에 속한 모든 응용 에이전트를 작업 요청에 관계없이 처음부터 구동시킨다고 가정하였다. 이러한 에이전트 정적 구동 방법은 에이전트 관리를 단순하게 해주는 이점을 제공하지만 워크플로우 관리나 전자상거래와 같이 매우 많은 수의 에이전트로 구성되는 응용 분야에서는 시스템 과부하와 자원의 낭비 등 많은 문제점을 초래한다. 동적 에이전트 관리는 이에 대한 해결책으로 아주 많은 수의 에이전트를 포함하는 다중 에이전트 시스템에서 현재 수행중인 작업에 관련된 에이전트만을 선별하여 구동시키고, 작업이 끝난 에이전트는 종료시킴으로써 자원의 낭비를 막고 에이전트간의 상호작용 시에 요구되는 에이전트 통신의 복잡도 부담을 감소시키는 효과를 낸다. 본 논문에서는 자바로 에이전트 관리 시스템을 구현하고, 이 관리 시스템을 통해 각기 다른 언어로 개발된 응용 에이전트가 분산된 환경에서 상호 협력을 통해 작업을 수행할 수 있는 기법을 제안한다. 사용자나 다른 에이전트의 요청으로 에이전트를 동적으로 수행시키기 위해 다른 언어로의 확장을 가능하게 하는 Java Native Interface(JNI)를 사용한 기술 및 이러한 이질적인 에이전트간의 원활한 통신을 위해서 KQML 언어 인터페이스를 통한 통신 기능을 제안한다. 이질적 에이전트의 동적 관리를 가능하게 함으로써 다중 에이전트 시스템의 자원 이용 효율성과 확장성을 높이고 다양한 환경 변화에 대한 적응성과 개선된 협동능력을 제공한다.Abstract It has been assumed that all application agents in a multi-agent system are pre-invoked and remain active regardless of whether they are actually used. Although this kind of static agent invocation simplifies the management of agents, it causes several problems such as the system overload and a waste of resources, especially in the areas of the workflow management and the electronic commerce that consist of tens and even hundreds of application agents. A solution for these problems is the scheme of dynamic agent management that selectively invokes only agents that are actually requested and terminates them when they are no longer needed. This method prevents a waste of system resources and alleviates the complexity of agent communications.This paper proposes an agent management system implemented in Java that supports interactions between application agents that are developed using different languages. Dynamic agent invocation is accomplished by Java Native Interface(JNI) that links two heterogeneous methods, and by KQML language interface that facilitates the communications between heterogeneous agents. This scheme of dynamic agent management provides efficient resource usage, easy extensibility, dynamic adaptibility to changes in the environment, and improved cooperation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.68-75
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• 2019

This descriptive research study identified the factors affecting the nursing process confidence of nursing students. The study's data was collected from June 13th 2017 to June 30th, 2017. Informed consent was received from 129 students who were in their second year of nursing college. The collected data was analyzed using SPSS WIN 18.0 program. The score for self-directed learning ability was 3.45, the score for a critical thinking disposition was 3.55, and the score for nursing process confidence was 3.68. There was significant positive correlation between nursing process confidence and self-directed learning ability (r=.572, p<.001) and critical thinking disposition (r=.488, p<.001). The factor affecting the confidence in the nursing process was self-directed learning ability(32.2%). Educational methods based on building the self-directed learning ability are needed to enhance the nursing process. There are limitations in discussing the results of this study due to the lack of prior research. Further study is needed to confirm the results of this research and the relationships it revealed.

• Journal of Convergence for Information Technology
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• v.8 no.3
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• pp.183-191
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• 2018

This study is to examine the effects of Socially Prescribed Perfectionism on depression by Intolerance of Uncertainty and Unconditional Self Acceptance, and to well being to improve the positive life of college students. This study is conducted on 238 college students who are influenced by Socially Prescribed Perfectionism, Intolerance of Uncertainty, Unconditional Self Acceptance, and Depression. This study analyzed a questionnaire consisted of a sub-component of the Multidimensional Perfectionism Scale (MPS), a Intolerance of Uncertainty Scale(IUS), an Unconditional Self Acceptance Questionnaire-R(USAQ-R), and a depression scale (CES-D) and verified correlation analysis and structural equation model. The results of this study showed that socially prescribed perfectionism had significant negative correlations with intolerance of uncertainty, and had significant positive correlation with unconditional self acceptance. The results of the structural equation model showed full mediating effect of the intolerance of uncertainty and unconditional self acceptance between Socially prescribed perfectionism and depression, Finally, implications and suggestions are suggested in this study.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.617-626
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• 2021

This study was conducted to explore self-directed learning, learning flow, academic self-efficacy and academic achievement on nursing students and to investigate the major factors that influence academic achievement. Data were collected from October 15 to 19, 2021, data were analyzed utilizing the SPSS WIN 21.0 program. Participants in this study were 145 students of the college in J city. As a result of the study, self-directed learning was 3.67±0.65 points out of 5, learning flow was 3.35±0.76 points out of 5, academic self-efficacy was 3.43±0.94 points out of 5, and academic achievement was 3.85±1.13 points out of 5. The relationships between self-directed learning, learning flow, academic self-efficacy and academic achievement showed significant positive correlations. As a result of multiple regression analysis, factors influencing the academic achievements of nursing students were found to be learning flow and academic self-efficacy. Therefore, in order to increase academic achievement in nursing college students, it is necessary to develop educational programs to increase the academic self-efficacy, and to continuously check the effect.