• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.1-9
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• 2014

Recently, natural aggregate was adequate to supply the demand due to increase of building construction. National pollution induced by construction waste caused by the reconstruction and redevelopment was cited as the major social issues in Korea. Therefore, government are required by law to use the recycled aggregate. In order to consider safety, KS F 2573 recommend that recycled aggregate with below design strength 27MPa and replacement ratio of 30%. This study on flexural behaviors of reinforced concrete beam was conducted and the specimens employed in test were planed with high strength concrete (40, 50 and 60MPa) and recycled aggregate replacement ratio (0, 30, 50, 100%). Although the flexural strength of reinforced concrete beam has trendy to decrease with increase of replacement ratio, it is meet to KCI 2007. The comparison results show that reinforced concrete beam using recycled aggregate can apply as flexural member in building construction.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.5
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• pp.55-63
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• 2018

Recently, the use of duplex stainless steel which with a two-phase microstructure (equal mixture of ferrite and austenite) has been increased in a variety of industrial fields due to higher strength leading to weight saving, greater corrosion resistance(particularly, stress corrosion cracking) and lower price. However, currently, stainless steels are not included in the structural materials of Korean Building Code and corresponding design standards are not specified. In this paper, experimental studies have been performed to investigate the structural behaviors of duplex stainless steel (STS329FLD) bolted connection with two bolts for providing the design data. Main variables are shear connection type (single shear and double shear) and end distance parallel to the direction of applied force. Fracture modes at the final step of test were classified into typical block shear fracture, tensile fracture and curling. Curling occurrence in single shear connection led to ultimate strength drop by up to 20%. Test strengths were compared with those by current design specifications such as AISC/AISI/KBC, EC3 and AIJ and proposed equations by existing studies. For specimens with no curling, Clement & Teh's equation considering the active shear plane provided a higher strength estimation accurancy and for specimens with curling, Kim & Lim's equation considering strength reduction by curling was also overly unconservative to predict the ultimate strength of curled connections.

• Journal of Korean Home Economics Education Association
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• v.18 no.4 s.42
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• pp.25-38
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• 2006

The purpose of this study was to investigate the education effect of eating habit unit in 'technology home economics' upon nutrition knowledge eating befavour of students. The eating habit unit in 'technology home economics' was taught with respect to 509 middle school 1st grade students, and preference acknowledgement were examined. Education effect was also examined by analyzing the changes in nutrition knowledge and eating befavour due to the education. Study results revealed that the level of acknowledgement for eating habit unit was positive while majority of the students thought that education contents were emphasized on the theory mainly because of insufficient class hours. Therefore, in order to let students know them better and make the best use of them, it is required to increase the class hours and research opportunity for practice class related with daily life. Through the middle school 'technology home economics' eating habit unit education, positive effect in part of eating habit area was observed and nutrition knowledge was enhanced after the education in both male and female students group. Judging from the results, less enhancement was observed in eating habit compared to the nutrition knowledge increase. Therefore, it can be concluded that continuous and a long range nutrition education is needed to transform the acquired nutrition knowledge into eating habit.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.9-20
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• 2015

Nowadays, Smart Wallet technology trend that is able to save users' consuming costs and also retain users' redundant behaviors such as Single-tapping, One-way communication, Integrated ID, has been issued in recent Mobile Industrial Fields. As one of Smart Wallet functions, Integrated ID is proposed for users' convenience, handiness, and immediate responses. It is designed for the effective management of users' IDs which are easy to be forgot because of its unusual structures. To be detail, instead of user, Integrated ID system can certificate users identification from various online sites (where user resisted) authorization requests via one-clicking, not putting identification data in each sites. So, this technology would be helpful much to a certain user who has lots ID and its Password in multiple Online shopping companies by establishing integrated ID. However, although Integrated ID has lots advantages to be used, most Mobile Service Companies has hesitated to apply Integrated ID service in their shopping systems because this technology requires them sharing their users' data. They have worried that this service would be not helpful to gain their profits. Furthermore, Users who join in multiple shopping companies and use Integrated ID services also are difficult to decide which company they have to save their points in before payment because this system could not show any financial benefit analysis data to their users. As following facts, via this paper majorly we propose the advanced Integrated ID system which concern shopping point management. Basically, this system has a strong security payment service and secure network services like other mobile Shopping systems. Additionally, this system is able to service (or to support) shopping -point -saving guide for customers' financial benefits and conveniences.

• Journal of Korea Port Economic Association
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• v.31 no.3
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• pp.141-153
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• 2015

This paper is an attempt to analyze the comparative advantage of Busan Port to China. For this, we use the market comparative advantage index, which is a version of the revealed comparative advantage index. The market comparative advantage index (MCA) uses trade patterns to identify the sectors in which a region has a comparative advantage, in this case by comparing Busan Port's trade profile with the world average (China). The indices are calculated at the commodity level of the HS four-digit classification. The export data used in this study are obtained from the Korea International Trade Association. Exports to China accounted for almost one third of Korean exports in 2014. There are, however, structural differences among the main export items of Busan Port. This paper, therefore, employs MCA indices to reveal the behaviors of the ten main export items, which are "HS3920-other plates/sheets/film/foil of plastics," "HS7606-aluminum plates/sheets/strip," "HS8479-unspecified machines/medical appliances," "HS8486-machines for semiconductor devices or wafers," "HS8529-parts for transmission apparatus for television," "HS8703-motor vehicles for the transport of persons," "HS8708-parts of motor vehicles," "HS9001-optical fibers," and "HS9013-liquid crystal devices." The study shows that export competitiveness of nine items increases, the exception being HS8703. However, China's import ratios of seven of the nine items for which the MCA indices go up are on the decrease, which means that it would be hard to expand the export market for these seven items, despite the higher MCA indices. Since the shares of the port's total exports to China of HS3907, HS8486, HS8529, HS9001, and HS9013 in total exports to China increase together with China's import ratio decreasing, these items may have promising export markets. MCA increases of HS7606 and HS8479 are attributable to China's lower import ratio, rather than a higher export share, so higher MCA indices do not guarantee higher export competitiveness for these items.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.632-648
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• 2002

The purpose of this study was to investigate a process of change which was made by a science teacher for one-year long in-service education program in terms of constructivist teaching behaviors and beliefs. The in-service program was featured by the use of learning cycle model and Science-Technology-Society approach. One of science teachers, who attended an one-year long in-service program was selected for this study. She developed three teaching materials for the duration. The three teaching materials were analyzed to find components of Science-Technology-Society and the integration of science content and real life context. Also, an interview was performed to assess changes in her perspectives on science, science teaching and science learning through the program. The first material was constructed in the form of learning cycle with little emphasis on STS. The second material was embedded with personal matters such as a refrigerator. The final one was shown to be organized with science content in a personal context and with focus on the role play. The interview also showed that her perspectives on science and science teaching have changed toward the constructivist's during the participation in the in-service program. It is suggested that a long-term in-service program should be developed and implemented so that the science teachers may become constructivist teachers.

• Korean Journal of Occupational Health Nursing
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• v.10 no.1
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• pp.74-92
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• 2001

This study was carried out to investigate the types of health documents for nurses, the content of informations in the documents, and writing behaviors of occupational health nurses. Health documents were collected from 7 nurses who were working in 7 group occupational health agencies (GOHA) located at Seoul and Inchon area in Korea. The collected health documents written in January to June 1999 were analyzed, and revealed the following results. 1) The occupational health nurses were using 9 to 18 different types of health documents. The contents of the documents were considered quite similar to each other with slightly different headings and items to record. Among different types of health documents. Health Management Card for Workplace', Nursing performance sheet and Workplace environmental checklist were in common among nurses and were used for content analysis. 2) The 'Health Management Card for Workplace' was the only formal sheet of small-scale-enterprises (SSE) for health management, in which health and safety related information was recorded. The information on nursing services were recorded on the Nursing performance sheet, which has slightly different names on each type with similar contents. The Workplace environment checklist was for the information on general work environment management and mainly status of workplace hygiene. This checklist is to be used by or with nurses among the 3 types health professional team such as doctor, hygienist, and nurse, but it seemed not being used frequently by nurses. 3) Analysis on recording tendencies of nurses revealed that the writing styles of occupational health nurses were associated with 'memo' using a few number of words and short sentences. The amount of information by this kind of recording style was considered not enough for health management situation. The possible reasons for nurses to use this writing style might be insufficient time for recording and improper designed format of health documents. Because nurses working in SSE spend more time on the roads to visit workplaces, nurses may not found enough time for recording properly within their working time. In addition, the health records were designed to focus on the frequency of nurse's performance in certain types of work rather than on the method they used to deal with health problems. In conclusion, this study suggests that some steps are necessary to develop health documents and recording system which is appropriate to occupational health nurses. The educational need for nurses on appropriate recording behavior is also recommended.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.78-91
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• 2017

In this study, we conducted a comparative study on user's perception and behavior on public system service (PSS) using institutionalism theory and MGA (multi-group analysis) methodology. In particular, this study focuses on how institutional isomorphism is applied to public system services and how MGA can be implemented correctly in a variance based SEM (structural equation model) such as PLS (partial least square). A data set of 496 effective responses was collected from pubic system users and an empirical research was conducted using three segmented models categorized by public proximity theory (public firms = 113, government contractors = 210, private contractors = 173). For rigorous group comparisons, each model was estimated by the same indicators and approaches. PLS-SEM was used in testing research hypotheses, followed by parametric and non-parametric PLS-MGA procedures in testing categorical moderation effects. This study applied novel procedures for testing composite measurement invariance prior to multi-group comparisons. The following main results and implications are drawn : 1) Partial measurement invariance was established. Multi-group analysis can be done by decomposed models although data can not be pooled for one integrated model. 2) Multi-group analysis using various approaches showed that proximity to public sphere moderated some hypothesized paths from quality dimensions to user satisfaction, which means that categorical moderating effects were partially supported. 3) Careful attention should be given to the selection of statistical test methods and the interpretation of the results of multi-group analysis, taking into account the different outcomes of the PLS-MGA test methods and the low statistical power of the moderating effect. It is necessary to use various methods such as comparing the difference in the path coefficient significance and the significance of the path coefficient difference between the groups. 4) Substantial differences in the perceptions and behaviors of PSS users existed according to proximity to public sphere, including the significance of path coefficients, mediation and categorical moderation effects. 5) The paper also provides detailed analysis and implication from a new institutional perspective. This study using a novel and appropriate methodology for performing group comparisons would be useful for researchers interested in comparative studies employing institutionalism theory and PLS-SEM multi-group analysis technique.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.50-55
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• 2009

To understand the status of the migrating Oriental Honey Buzzard(Pernis ptilorhynchus) in Korea, we carried out a preliminary study on the number and local movements of the Honey Buzzard from September 2005 to October 2007 at Hongdo Island, Jeonnam Province, Korea. A total of 702 Honey Buzzards in 2005, 404 individuals in 2006, and 659 individuals in 2007 were recorded during the fall migration season, but during the spring migration season only two and eight birds were observed in 2006 and 2007 respectively. The migrating Honey Buzzard showed peak numbers from 20 September to 5 October at the study site. According to observation of arrival time of538 Honey Buzzard in October 2007, a total of 2l6 birds(40.l %) were passing over Hongdo Island between 7:00 AM to 8:00 AM, rising skyward on columns of warm air. This suggests the use of thermal currents and avoidance of nocturnal movement for crossing water. They preferred moderate winds(<5 m/s in speed) from northwest, but the migrating number apparently decreased in case of strong winds (${\geqq}5 m/s$). This suggests that wind speed and direction are important environmental factors for migration of the Oriental Honey Buzzard. At present, it is unclear which breeding population(from north-eastern China or Japan) passes over Hongdo Island. Moreover, it is difficult to prove migration route and to understand migratory behaviors of the Oriental Honey Buzzard in Korea. To prove the breeding sites and routes of the migrants over the study site, we need more detailed and further studies such as satellite tracking researches.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.137-147
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• 2016

The purpose of this study was to analyze the perception factors of a pedestrian environment that affect pedestrian environment satisfaction(PES) and determine the relationship between PES and the expected effects of health promotion. The targeted areas of study are neighborhood parks in Suseong-gu, Daegu city. First, regarding the results for the evaluation of pedestrian environment perception, 'Gentle slope' was rated the highest, while factors regarding pedestrian safety such as 'Lots of unpleasant elements', 'Risk from biking and motorcycling' and 'Many obstacles on sidewalks' were rated low. A stepwise regression analysis showed that factors such as 'Fresh air', 'Beautiful scenery', 'Continuity of the sidewalks', 'Various attractions', 'The shade of trees' and 'Lots of unpleasant elements' influenced the PES. Therefore, creating fresh air and shade trees by planting trees and removing unpleasant elements from pedestrian areas are important. Also, it is necessary to cultivate beautiful scenery and attractions through street improvement and improve the continuity of the sidewalks. Finally, in terms of path analysis, PES influenced the frequency of park use, the expected effects of physical and mental health promotion both directly and indirectly.