• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Journal of The Korean Association For Science Education
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• v.33 no.5
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• pp.911-931
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• 2013

The purpose of this study was to analyze pre-service teachers' reflective discussion on their practical work-based teaching by focusing on the components of instruction and the connectivity of discussion. Eight after-class discussions were recorded and transcribed, and finally analyzed in terms of theoretically driven categories such as aims, teacher knowledge and learner response which also respectively reflect the actual flow of planning, implementation and evaluation of the teaching practice. The result showed that in their discussion about students, conceptual understanding and scientific skill components were most emphasized, while teaching method and strategy were most frequently addressed in the discussion about teacher knowledge. But this also revealed problems in their discussions such as the lack of discussion about inquiry and student interest, difficulties in clarifying theoretical terms and the lack of discussion about instructional models and theories. Meanwhile, pre-service teachers' discussions were limited in terms of connectivity between the components of instruction, meaning that their discussion tended to deal with each component separately rather than occurred in connection with each other. Furthermore, when connections were made during the discussion, only few components of instruction appeared. Based on this result, the paper suggests the need to develop tools to facilitate effective reflection in ways that incorporate various components of instruction and enhance connectivity between the components and between the instructions.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.178-185
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• 2015

Purpose: The purpose of this study was to conduct a comparative assessment on the satisfaction level for the two interfaces of surgical guide system (SimPlant and R2GATE), the design and convenience of manufactured surgical guides and the importance of using the surgical guides thereof by means of survey. Materials and Methods: Hereupon, they simulated the implant surgical process by mounting the two manufactured systems of surgical guide on a dental mold, respectively. The study subjects were instructed to complete the questionnaire as to the satisfaction level upon completion of the simulated surgery. This study summarized the data of each question after collecting the completed questionnaires. Then, this study analyzed the summarized data by utilizing statistical program SPSS 20.0 (IBM). Results: R2GATE had a higher value of the satisfaction level on the design and convenience of manufactures surgical guides. R2GATE group ($7.33{\pm}1.26$) was found to have a higher value in terms of the overall satisfaction level compared to SimPlant group ($6.67{\pm}1.26$) (${\alpha}$ = 0.05). Conclusion: The user satisfaction level on the surgical guide manufactured for R2GATE system was to such an extent as it can be widely used in clinical environment. Moreover, the surgical guide manufactured as R2GATE system can guide both the length and direction of a drill simultaneously. As a result, it is highly recommended for those beginners who do not have a lot of experience in implant placement.

• Sleep Medicine and Psychophysiology
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• v.19 no.2
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• pp.89-96
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• 2012

Objectives: Individuals differ in their biological rhythms. This study investigated the association between the morningness-eveningness and sleep patterns, daytime sleepiness and fatigue in Korean male adolescents. Methods: Participants were 501 eleventh grade male students ($16.9{\pm}0.2$ years of age) in one male high school in Seoul. Each student completed the Korean translation of composite scale (KtCS), Epworth sleepiness scale (ESS), Fatigue Severity Scale (FSS) and a questionnaire about their sleep schedule. Results: The evening group had shorter weekday sleep time than the intermediate (p<0.001) or morning group (p=0.029). The evening group had more daytime napping (16.8%, p<0.001), high rate of caffeine use (58.8%, p<0.001) and snoring (18.5%, p=0.037). The evening group showed more daytime sleepiness (8.7, SD=3.2, p<0.001) and severe fatigue (4.4, SD=1.2, p<0.001) than the intermediate or morning group. Conclusion: Adolescents with eveningness have higher problems in weekday sleep, daytime sleepiness and fatigue. An intervention program for sleep problem in these adolescents should be considered.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.523-526
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• 2017

In modern recently technology, 3D-Audio is used to enhance immersion in Virtual Reality. This includes interest of people about VR and AR, which related to the field of computer graphics. In fact, a lot of research has been carried out in recent years into a 3D sound field. However, the existing 3D generator device used for virtual reality does not contain Doppler effect occurred by the sound comes to or leave from a listener, while an angle from the listener and the altitude of the source sound are applied. Therefore, this paper present 3D real sound utilizing Doppler effect with spatial-rotation-speaker. We map the source sound in 3D-space into a real space where a user stays and present 3D real sound by manipulating with rotation angle, phase difference, sound output volume of the sound in 3D-space, according to the location of a virtual source sound. Utilizing both natural Doppler effect of rotating sound that is occurring by spatial-rotation-speaker and artificial Doppler effect generated by frequency-modulation of sound quality could improving the virtual reality for sound condition for perspective listening.

• The KIPS Transactions:PartD
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• v.15D no.4
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• pp.513-522
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• 2008

Service-Oriented Architecture(SOA) is an method to develop applications by developing and publishing reusable services which potentially be used in various applications, and discovering and composing right services dynamically. SOA adopts a paradigm of publish-discover-invoke, which is considerably different from object-oriented and component-based development(CBD) approaches. The service in SOA is different from function in procedural programming, object in object-oriented programming, and component in CBD, and its fundamental requirement is a high level of reusability and applicability. In SOA, service providers and service consumers are loosely coupled since the providers try to develop reusable services and the consumers try to locate right services without knowing much about the providers and their published services. Moreover, the process of searching, choosing and invoking right services is not presented in conventional programming paradigms. Therefore, conventional approaches to developing user interfaces and invoking the functionality on servers through JSP, and RMI in object-oriented programming cannot well be applicable to designing clients’ programs in SOA. Therefore, there is a high demand for a practical and systematic process for developing clients’ applications, and the such a process should be devised by considering key characteristics of services and SOA. However, little work on this area is known to date, and there has not a process for client side just except few guide lines for developing service client. In this paper, we propose a practical and systematic development process for developing clients' applications in SOA. Then, we define instructions for carrying out each activity in the process. To show the applicability of the proposed work, we show the result of applying our process in developing a services application for searching and booking hotels.

• Korean Journal of Construction Engineering and Management
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• v.7 no.5
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• pp.115-127
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• 2006

Although the Korean government have made a plan of housing market with supply and concentrated on the welfare of the people, there are still a lot of problem in housing market for lack of a long-term vision and consistent policy of the government. The plan of 115% of housing diffusion in 2012 is in progress after its acquisition of 100% in 2002, but there are no changes in the rental housing rate of 43% in 2003. In addition, there are getting worse circumstances in the instability of housing market and the low-income bracket, because of the Korean construction firms' bankruptcy with an increase of unsold hosing and a rapid increase of housing prices. The government have made the strategy of revitalizing the economy and regional development by means of a million public rental housing plan for the low-income bracket and welfare. This paper introduces the basic information of the subjective strategy establishment with the analysis of the reciprocal action of influence factors for public rental housing by system dynamics theory and the effect of public rental housing in housing supply market which has a long-term dynamic form.

• Korean Journal of Construction Engineering and Management
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• v.13 no.5
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• pp.64-75
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• 2012

Today organizations are making considerable efforts in order to maintain excellent talent, and in particular, they are focusing on understanding their intentions of changing jobs which are most highly correlated with job turnover. In the case of architectural design firms, its intensity of work is very high unlike industrial settings, and it not only takes much time to cultivate new men of talent and but also is characteristic that employees can change livery easily because of the flexible labor market. The turnover rated by National Statistical Office indicates that specialized, scientific and technical service industry including the architectural design firm has a relatively high turnover rate compared to the average of the turnover rate of the overall industries. However, studies on intentions of changing jobs until now were conducted focused on employees engaged in other industrial areas, and it is true that studies regarding intentions of changing jobs of practitioners of architectural design firms are very insufficient. In this context, the present study aimed to draw determinants affecting intentions of changing jobs of practitioners of architectural design firms, to objectively understand the practitioners' intentions of changing jobs through importance analysis by each factor based on this and to make a comparative analysis of differences between the large scale architectural design firms and the small and medium sized architectural design firms.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.171-183
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• 2013

Domestric Construction & Engineering market has been long in recession due to the global economic crisis. Domestic construction industries consequently looks at overseas construction markets where relatively more construction projects are constantly required. In order to provide meaningful information for Korean engineering companies to keep the pace with the changes in the construction industry, various construction related date and statistics are analyzed. In addition, previous research from the related organizations and construction engineering companies are closely reviewed. Investigation of preliminary data and research have been conducted to draw remedies for their overseas expansion. Moreover, it is attempted to classify foreign markets as the Asia, Africa and etc. (Europe, North America/the Pacific and Latin America) to provide the list of first target countries and its regional market information focusing on their bidding system. This study had tried to show comparative analysis of different bidding procedures between Korea and the selected countries to suggest measures of improvements for the domestic bidding system. Finally, this study suggested policy recommendations to meet the requirement of bid qualification to advance the global market that was suggested with validated clustering bidding data.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.3-11
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• 2013

Recently according to increasement of the single family and dual-earner couples, the number of infants and young children stays on a long time to the childcare facilities. this is increasing the importance to improve the physical environment. However, the operating and maintenance costs of the national-public childcare facilities have taken effect of the unfair support issues of municipality's financial situation. Especially, because of the lack of the operating and maintenance costs of the facility and the shortage of facilities equipment maintenance repair costs, nursery operations and Maintenance items are needed to distribute appropriately. Therefore, this study is to estimate the importance to facility operations and maintenance items based on "Kindergarten and Childcare Facilities"presented at the Child Care Policy Study. we are expected to allocate appropriately of operation and maintenance cost of a limited budget. In particular, those can be considered for operation and maintenance cost about the National-Public Childcare Facilities and be determined to a safe and pleasant environment to kindergartens through the appropriate operations and maintenance support.