• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.5
• /
• pp.601-610
• /
• 2023

The comprehension of water-level behavior in rivers is essential for effective flood and river environmental management. The objective of this study is to propose a methodology that can be used by field engineers engaged in actual practice, to readily identify the characteristics of water-level behavior during flood events. To this end, a total of 45 historical water-level records from 2010 to 2022 year, which provide flood information for the flood vulnerable districts of the Han River, were obtained. A Water-level Rise Behavior Curve (WRBC) was developed and suggested to quantify the amount of water-level rise per unit time during flood. As a result, the water-level rises by more than 80% of the total rise within the first 6.2 hours, followed by a gradual rise. The time required to achieve a particular equilibrium varied depending on the area and runoff characteristics of the upstream. Furthermore, the study revealed that the WRBC provides a statistical representation of the water-level rise trend during floods, and can be effectively utilized for flood mitigation measures in waterfront spaces and irrigation facilities.

• Journal of Korean Elementary Science Education
• /
• v.42 no.1
• /
• pp.34-46
• /
• 2023

To investigate the trends in science education research related to play and derive implications for elementary science education research, we analyzed 109 research articles on play in science education published both in Korea and abroad. First, the number of research studies conducted abroad has been steadily increasing since 2009, with the highest number targeting middle school students. Conversely, domestic research has the highest number of papers targeting elementary school students. Second, in terms of research methods, quantitative methods were the most commonly used. Third, the use of questionnaires was the most frequently published research method, while the use of observation and products was smaller in number in domestic studies compared to those conducted abroad. Fourth, In the aspects of the contents, more research was conducted in the field of physics than in other areas. In case of researches for elementary school students, domestic research was focused on four areas of science. Fifth, among the studies exploring effectiveness, the 'cognitive domain' was the most studied, followed by the 'science-related attitude domain' and the 'inquiry and practice domain'. Sixth, the use of play was high in the following order: online games, video games, virtual play, and games with rules. For domestic researches, studies on analog play were most frequently reported, and the ratio of digital games in abroad was higher than that of others. Seventh, the highest number of papers used teacher-directed play, and this tendency was more noticeable in domestic studies.

• Journal of the Korean Geotechnical Society
• /
• v.26 no.11
• /
• pp.47-61
• /
• 2010

To predict the settlement rate of a ground area that incorporates vertical drains, it is desirable to conduct various kinds of advanced field and laboratory tests for hydraulic properties. However, it is urgently needed to appropriately evaluate the hydraulic properties using the results of conventional soil tests which are extensively used for local practice. To achieve this purpose, a number of CPT dissipation test, laboratory permeability and consolidation tests were performed at five sites in the floodplain of the Nakdong River delta, and the test data were comprehensively analyzed. As a result, it is found that the coefficients of horizontal consolidation ($C_{h,NC}$) and permeability ($k_{h,OC}$) of the clay agreed well with those of the CPT-based methods proposed by Baligh and Levadoux (1986). The values of $C_{h,NC}$ and $k_{h,OC}$ were in the range of $0.4{\sim}3.0\;cm^2/sec$ and $0.40{\sim}2.50\;cm^2/sec$, each of which slightly increases or decreases with depth, respectively. It was also inferred that these trends seem to reflect the depositional environments of the clay.

• Journal of the Korean Society of Floral Art and Design
• /
• no.41
• /
• pp.93-114
• /
• 2019

The purpose of this study is to analyze the characteristics and problems of the content of flower design education videos on YouTube and to search for improvement direction. The subjects of analysis were 129 pieces of videos uploaded in the last one year including 'craftman floral design' as a search term. The result shows that contents covered were practical lectures, theory lectures, test related tips, job and character introduction, test work, educational guidance and publicity. The production format could be divided into studio lecture, classroom lecture, video feature, interview, Vlog, and television program. The hub-type programming strategy that periodically uploads the videos satisfying the target audiences' interests is mostly applied. The type of lecture covered 'practical skill test' got a good response from the users. Overall, content diversity, interaction between creators and users, and harmonious programming strategies are lacking. In order to improve this, it is necessary for emotional and expressive creators to pioneer differentiated fields and practice based on actual field. The introduction of interactive elements such as games and quizzes and the application of new media technologies such as VR and AR are worth trying. Three strategic types of 'hero', 'hub', and 'how to' should be applied complementary. As the demand for education content related to flower design is expected to expand in the future, it is required to develop content that can be used in various platforms, foster professional creators, and develop associated business models.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.6 no.10
• /
• pp.107-120
• /
• 2016

The purpose of this study is to analyze research trends of bilingual education which are focused on foreigner parent's language education for children from multicultural families in South Korea. After searching, total 36 research papers were selected and analyzed. Results from this study showed that, (1) relevant researches started from 2009, later then the number of researches kept about 4-6 yearly and reached the peak of 11 (31%) in 2004; (2) a large majority (75%) of the analyzed researches published in the magazines relative to a field of language education or children education; (3) diverse research methods were employed, and the number of researches applied on qualitative research methods is similar with on quantitative ; (4) the researches mainly studied on the members of multicultural families (67%), and 10 analyzed researches investigated parents and children together 28%, and 9 targeted on parents or one of them (25%), and 5 just on the children from multicultural families (14%). and, (5) The research topics mainly divided into four fields current bilingual education programs (31%), bilingual education (31%), interaction related to bilingual education (22%), suggestion on policy improvement(17%). Based on the results, discussions and implications for further research and practice on bilingual education and foreigner parent's language education will be provided.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.11 no.3
• /
• pp.287-301
• /
• 2009

The novel cut-and-cover tunnel construction method using rib-reinforced pre-cast arch segments has been recently developed and applied for practice to secure a structural stability of high covering and wide width section tunnels. Cut-and-cover tunnels are usually damaged by the seismic behavior of backfill grounds in case of a low covering condition. Seismic analyses are performed in this study to characterize the dynamic behavior of rib-reinforced pre-cast arch cut-and-cover tunnels. Seismic analyzes for 2 lane cast-in-place and rib-reinforced pre-cast arch cut-and-cover tunnels are carried out by using the commercial FDM program (FLAC2D) considering various field conditions such as the covering height embankment slope and excavation slope. It can be concluded that the amplification of seismic wave is reduced due to an increase in the structural stiffness induced by rib-reinforcement. The results show that the rib-reinforced pre-cast arch cut-and-cover tunnels are more effective against the seismic loading, compared to the cast-in-place cut-and-cover tunnels.

• Journal of Service Research and Studies
• /
• v.11 no.3
• /
• pp.1-16
• /
• 2021

Recently, crowdfunding has been receiving increased attention due to the variety of novel ways it provides for connecting funders and fundraisers. Concurrently, however, it has been criticized on the grounds of information asymmetry. We are interested in whether information collected from an asymmetric information source significantly influences crowdfunding success. Through this study, we would like to establish a social field of convergence pursued by Serve Science and to conduct practical research and practice together. First, we investigated the importance of interaction between funders and fundraisers within the crowdfunding platform. In the "comments" section, communication between funders and fundraisers reduces the degree of asymmetric information. In the aspect of presumable funders, they should make the best of the "comments" section to collect more solid information without losing return on their investment. Second, we analyze sentiment-based optimistic and pessimistic information from the "story" (asymmetric source) and "comments" sections. In conclusion, it shows that the optimistic and pessimistic information of the "comments" section has a great impact on crowdfunding success and that the influence of the "story" section is limited to pessimistic information under certain conditions. The crowdfunding platform is an innovative and productive way for startups and entrepreneurs to start a business, and since information an important role in the success of crowdfunding, It can be seen that it is essential to focus on establishing the best communication methods.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.3A
• /
• pp.513-521
• /
• 2006

Many studies have been conducted on the high tension bolt friction connection in the view of the field practice. Those effort, however, unfortunately have not been appropriately applied in the design specifications. Recently, particularly for steel bridges, rationalization of design takes greater attention from designers and hence, demand on rationalization of high tension connection becomes more significant. The purpose of this study is to suggest direction for the rationalization of high tension bolt connection and to also provide fundamental information for the improvement of the design specifications. In order to accomplish the purposes, the design specifications in Korea was analyzed and compared with other specification from abroad, and was studied one of the most important factors including slip coefficient, and the specifications on the size of bolt holes. The effect of over-sized bolt hole and the reduction of axial force on bolt was evaluated through the experimental studies on the slippage of the high tension bolt connections. Other research topics included herein includes the difference of slip coefficients, the effect of over-sized bolt holes and the gap distance of members, and the application of filler plate and corrosion protected bolts. From the research results, it is known that the specifications in Korea apply a constant slip coefficient with respect to the contacted surface conditions while various coefficients are available depending on the contacted surface conditions. Therefore, it is recommended that the specifications in Korea also develop and detail the slip coefficient which can appropriately take account of the variation of the contacted surface conditions. It is also suggested that the limitation abroad on the over-sized bolt hole may be applied for enhancing the effectiveness of construction.

• Journal of Industrial Convergence
• /
• v.21 no.8
• /
• pp.59-67
• /
• 2023

This study aims to examine how individual variables (motivation to participate, leadership life skills, aging awareness), interpersonal variables (relations with subjects, colleagues, and employees), and institutional variables (recognition compensation, institutional education) affect the continuity of volunteer activities. To this end, a survey was conducted on women aged 40 to 64 working at volunteer centers and local volunteer institutions in Seoul for 20 days from August 2, 2019, and a total of 300 questionnaires were distributed and 298 copies were collected, of which 180 were used for the final analysis. For data analysis, frequency analysis, descriptive statistical analysis, correlation analysis, and hierarchical regression analysis were conducted. As a result of the analysis, it was found that leadership life skills and motivation for participation, relationships with colleagues as interpersonal variables, and recognition compensation as institutional variables had a positive effect on the continuity of volunteer activities. This study aims to provide practical and policy suggestions to revitalize and maintain the continuity of volunteer activities of middle-aged women, and basic data for the development of programs to be used in the field of practice.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.21 no.2
• /
• pp.103-114
• /
• 2019

In this study we examined the preferences of college life factors for students at Korea National College of Agriculture and Fisheries(KNCAF). Analytical techniques of unstructured data used opinion mining and text mining techniques, and the results of text mining were visualized as word cloud. And those results were used for statistical analysis of the students' willingness to farm after graduation. The items of the favorable survey consisted of 10 items in 5 areas including university image, self-capacity, dormitory, education system, and future vision. After classifying the emotions of positive and negative in the collected questionnaire, a dictionary of positive and negative was created to evaluate the preference. The items of 'college image' at the time of university support, 'self after 10 years' after graduation, 'self-capacity' and 'present KNCAF' showed high positive emotion. On the other hand, positive emotion was low in the items of 'college dormitory', 'educational course', 'long-term field practice' and 'future of Korean agriculture'. In the cross-analysis of the difference in the will to farming according to gender, farming base, and entrance motivation, the will to farm according to gender and entrance motivation showed statistically significant results, but it was not significant in farming base. Also in binary logistic regression analysis on the will to farming, the statistically significant variable was found to be 'motivation for admission'