• Computational Structural Engineering
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• v.7 no.3
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• pp.95-103
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• 1994

The safety related components in the nuclear power plant should be designed to withstand the seismic load. Among these components the integrity of reactor internals under earthquake load is important in stand points of safety and economics, because these are classified to Seismic Class I components. So far the modelling methods of reactor internals have been investigated by many authors. In this paper, the dynamic behaviour of reactor internals of Yong Gwang 1&2 nuclear power plants under SSE(Safe Shutdown Earthquake) load is analyzed by using of the simpled Global Beam Model. For this, as a first step, the characteristic analysis of reactor internal components are performed by using of the finite element code ANSYS. And the Global Beam Model for reactor internals which includes beam elements, nonlinear impact springs which have gaps in upper and lower positions, and hydrodynamical couplings which simulate the fluid-filled cylinders of reactor vessel and core barrel structures is established. And for the exciting external force the response spectrum which is applied to reactor support is converted to the time history input. With this excitation and the model the dynamic behaviour of reactor internals is obtained. As the results, the structural integrity of reactor internal components under seismic excitation is verified and the input for the detailed duel assembly series model could be obtained. And the simplicity and effectiveness of Global Beam Model and the economics of the explicit Runge-Kutta-Gills algorithm in impact problem of high frequency interface components are confirmed.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.3
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• pp.33-50
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• 1988

This study was executed to find out how to improve on the planting and use of the plants in Kangweon- Do by surveying the planting areas -gardens, parks, streets, schools, etc. - in five cities of this province, and to select available native plants by surveying the main mountains in this province. The results are as follows ; 1. The species number within surrey areas was 319 species. and the species of which planting frequency was very high were Hibiscus syriacus, Juniperus chinensis, Buxus microphylla v. koreana, etc.. 2. The species number of school trees and flowers of 202 schools in Kangweon-Do were 33 species, 32 species respectively. and the species of school trees and flowers that showed the highest preference were Juniperus chinensis, Forsythia koreana each. 3. The species number of flowers and trees designated in 22 City and Keun were 14 species, 7 species respectively, and the species of flowers and trees that presented the highest designation frequency were Rhododendron schlippenbachii, Ginkgo biloba each. 4. The street trees planted along the main streets in Kangweon-Do were 18 species and 84,939 individuals, and the ratio of Populus alba${\times}$glandulosa was the highest among occurrence individuals. 5, As for the composition ratios of life forms of plants within survey areas, the ratio of deciduous broad-leaved tree was the highest as about 56% and that of deciduous coniferous tree was the lowest as about 1.6%. The ratios of native species versus exotic were 43 : 57 6. Through these results, it was thought that the diversification of planing species, the selection of plants suitable to each space and the generalization of use of native species were needed. So 254 plants native to Kangweon-Do were presented to correspond to these requirements.

• Journal of Korean Home Economics Education Association
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• v.20 no.3
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• pp.145-161
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• 2008

The purpose of this paper is to find out the needs of housing contents in highschool Home Economics among students. The 105 housing contents and topics were chosen from the 3 textbooks and related references. The number of 516 questionnaire from 8 areas were used to analyze. Analyses indicated that respondents were more likely to favor Home Economics subject and one out of five wanted to select it. Average needs of the housing contents was above middle(3.4) and these was a little difference among 3 middle units in housing. The most needed unit was housing design. There was a more wide difference in 19 small units than in middle ones, ranged $3.00\sim3.91$. Individual contents showed the most variousness in needs from 2.89 to 4.30 in the middle unit of housing and environments, 3.00 to 4.01 in housing design, and 2.68 to 3.91 in housing management. The needs of additional contents were about the same as those textbook contents and it indicated that new textbook needs to adopt the newly demanded housing contents. Some of individual, family, and environmental characteristics were significantly related to the students needs. The higher positive attitude such as favor, interest, and selecting of the subject was related to the higher needs of housing contents. Residential areas and neighboring were also related to most of the needs of individual housing contents.

• Journal of Intelligence and Information Systems
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• v.27 no.3
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• pp.29-56
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• 2021

Recently, various types of products have been launched with the rapid growth of the e-commerce market. As a result, many users face information overload problems, which is time-consuming in the purchasing decision-making process. Therefore, the importance of a personalized recommendation service that can provide customized products and services to users is emerging. For example, global companies such as Netflix, Amazon, and Google have introduced personalized recommendation services to support users' purchasing decisions. Accordingly, the user's information search cost can reduce which can positively affect the company's sales increase. The existing personalized recommendation service research applied Collaborative Filtering (CF) technique predicts user preference mainly use quantified information. However, the recommendation performance may have decreased if only use quantitative information. To improve the problems of such existing studies, many studies using reviews to enhance recommendation performance. However, reviews contain factors that hinder purchasing decisions, such as advertising content, false comments, meaningless or irrelevant content. When providing recommendation service uses a review that includes these factors can lead to decrease recommendation performance. Therefore, we proposed a novel recommendation methodology through CNN-based review usefulness score prediction to improve these problems. The results show that the proposed methodology has better prediction performance than the recommendation method considering all existing preference ratings. In addition, the results suggest that can enhance the performance of traditional CF when the information on review usefulness reflects in the personalized recommendation service.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.2
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• pp.29-38
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• 2021

According to the theory of concentration recovery(ART), experiencing landscapes with healing properties can heal human mental fatigue caused by intentional concentration. The ART illustrates four healing qualities of the landscape. ART admits that various landscapes can have healing properties, the four healing properties of the landscape explained that the greater the perceptual strength, the stronger the healing effect. Until now, research on healing landscapes has been mainly done on natural and urban landscapes. The purpose of this study is as follows. First, eIt is intended to evaluate the healing characteristics of the Yangdong village landscape using RCS and investigate the impact of the healing characteristics on the visiting preference of the target landscape. Second, Evaluating the landscape image of Yangdong Village landscape, Investigating the effect of landscape images on the healing properties of landscape. This study was conducted in Yangdong Village, Gyeongju, 127 college students participated in the survey. SD 16 items to analyze landscape images and RCS 22 items from Laumann(2001) to evaluate healing properties were used as measurement tools. The findings are summarized as follows. First, The landscape image of Yangdong Village was analyzed through SD method, the analysis of the factors of Yangdong Village landscape image results in two factors: place and singularity. Second, It demonstrates the reliability and validity of RCS, Three factors were extracted from the factor analysis results. Third, Landscape images have a positive effect on the three healing characteristics of RCS. Fourth, Three healing properties of RCS have been shown to have a positive effect on visiting preferences, The order of influence on the relative visiting preferences was analyzed as attractiveness, fit, sense of escape, and sense of space. The findings suggest that future work requires research to re-validate the reliability of RCS. It is also necessary to analyze landscape images for various landscape types to specifically understand the effects on healing characteristics.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.51-60
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• 2021

Modern society is becoming more informed and intelligent with the development of digital technology, in which humans, objects, and networks relate with each other. In accordance with the changing times, a garden system has emerged that makes it easy to supply the ideal temperature, humidity, sunlight, and moisture conditions to grow plants. Therefore, this study attempted to grasp the concept, perception, and trends of smart gardens, a recent concept. To achieve the purpose of this study, previous studies and text mining were used, and the results are as follows. First, the core characteristics of smart gardens are new gardens in which IoT technology and gardening techniques are fused in indoor and outdoor spaces due to technological developments and changes in people's lifestyles. As technology advances and the importance of the environment increases, smart gardens are becoming a reality due to the need for living spaces where humans and nature can co-exist. With the advent of smart gardens, it will be possible to contribute to gardens' vitalization to deal with changes in garden-related industries and people's lifestyles. Second, in current research related to smart gardens and users' experiences, the technical aspects of smart gardens are the most interesting. People value smart garden functions and technical aspects that enable a safe, comfortable, and convenient life, and subjective uses are emerging depending on individual tastes and the comfort with digital devices. Third, looking at the usage behavior of smart gardens, they are mainly used in indoor spaces, with edible plants are being grown. Due to the growing importance of the environment and concerns about climate change and a possible food crisis, the tendency is to prefer the cultivation of plants related to food, but the expansion of garden functions can satisfying users' needs with various technologies that allow for the growing of flowers. In addition, as users feel the shapes of smart gardens are new and sophisticated, it can be seen that design is an essential factor that helps to satisfy users. Currently, smart gardens are developing in terms of technology. However, the main components of the smart garden are the combination of humans, nature, and technology rather than focusing on growing plants conveniently by simply connecting potted plants and smart devices. It strengthens connectivity with various city services and smart homes. Smart gardens interact with the landscape of the architect's ideas rather than reproducing nature through science and technology. Therefore, it is necessary to have a design that considers the functions of the garden and the needs of users. In addition, by providing citizens indoor and urban parks and public facilities, it is possible to share the functions of communication and gardening among generations targeting those who do not enjoy 'smart' services due to age and bridge the digital device and information gap. Smart gardens have potential as a new landscaping space.

• 한국노년학
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• v.38 no.4
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• pp.1035-1055
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• 2018

The purpose of this study is to investigate the relationship between public care and family care. Public care for older adults began in 2008 with the implementation of the Long-Term Care insurance in South Korea. Although the expansion of public care has the purpose of reducing the care burden for the family, it is not easy to say whether the developments of public care system reduce the amount of family care for older family members. Theoretically, public care and family care are expected to have various relationships depending on the degree of the role and function(substitution, hierarchical compensatory, task specific, supplementation, complementarity). And literatures have showed inconsistent results depending on the country, data, and methods. In this study, we analyzed the relationship between two care types focusing on home care services for older persons. Analyses were based on data from the second(2008) to sixth(2016) waves of Korean Longitudinal Study of Ageing(KLoSA). To investigate elderly care dynamics in the households, we pooled the data for four changes between two periods(2008-2010, 2010-2012, 2012-2014, and 2014-2016). This study used an analytic sample of 262 older adults, who are aged 55 over and experienced public care at least one point of time. We used Fixed-Effects(FE) model to analyze the differences within the same individuals under the condition that time-invariant unobserved factors are controlled. This study distinguished the cases of entry into public care and other cases of exiting public care. The results showed that older people who are dependent on public care are less dependent on family care than before. In both entry and exit groups, negative relations were maintained, but in the entering stage of public care, the degree of negative relations was relatively small, whereas in the stage of maintaining or departing from public care, relatively negative relations were strong. At the beginning periods, even though public care increased, family care did not decrease significantly. On the other hand, at the time of ending public care and relying on family care, family care increased significantly. The results of this study show that the relationship between public care and family care is close to hierarchical compensatory model and varies according to the stage of caring transition. Also, it was found that the cases of transition from public care to family care have the biggest burden of elderly care than other groups.

• Korean Journal of Heritage: History & Science
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• v.43 no.3
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• pp.334-365
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• 2010

Mother-of-Pearl craftwork sketch involves the whole process of making a piece of work. Therefore, it includes types, forms, sizes, and patterns of the work. Some information about when and by whom those works were manufactured and who ordered them are still found in some sketches. This paper seeks to find out popular types and patterns of the works in each period and its demand and the way of supply by examining the collection of approximately 1700 Mother-of-Pearl craftwork sketches from the period of Japanese colonization up to the present time, which are owned by Mr. Song Bang-wung, Important Intangible Cultural Heritage no.10. Typical patterns of sketches are the hua-jo(花鳥 : Flowers and Birds), the Sakunja(四君子 : Four Gracious Plants), cultural treasures, figures in folk tales, 'Su-bok(壽福)' characters, and landscape. The pattern sketches have changed according to the circumstances of Korean society. During the period of Japanese colonization from the 1920s to the 1940s the manufacture and the supply and demand of Mother-of-Pearl craftworks were controled by the Japanese government. As a result, many of the patterns were adjusted to the Japanese taste. Most of its customers were also Japanese. During the 1950s after Independence the American Military Forces appeared as new customers due to the Korean War. Thus, the traditional Korean patterns to decorate accessories adored by American soldiers gained popularity. Foreign Mother-of-Perls were imported from the late 1960s to the 1970s. They were bigger and more colorful than those of Korean and it enabled the sketches bigger and the patterns more various. The most popular pattern in this period was the pattern of cultural treasures, such as an image of Buddha, metalcraft works, porcelains and pagodas. In terms of a technique, new techniques, such as engraving and rusting were introduced. There was a great demand for Mother-of-Pearl craftworks in the 1970s as people were highly interested in them. They were entirely made to order and there was a large demand from diverse organizations, furniture dealers and individuals. And the Mother-of-Pearl craftwork was in full flourish in the 1970s due to the country's economic development and the growth of national income. Mass production of the works was possible and the professional designers who drew patterns actively worked in this period. The favor of Mother-of-Pearl craftworks declined in the 1980s since the built-in furniture and the Western style of furniture became prevalent due to the change of housing into apartments. But it seemed that the manufacture of Mother-of-Pearl craftworks revived for once the technique of Kunum-jil(끊음질 : cutting and attaching) became popular in Tong-young(統營). After the 1990s, however, the making of Mother-of-Pearl craftworks gradually declined as the need of them decreased. Now it barely maintains its existence by a few artisans.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.224-255
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• 2022

This study was carried out to examine the changes in vascular flora in the first and second surveys targeting 32 outstanding forest wetlands in Jeonnam area including Gwangju metropolitan city, and based on this, establish a future monitoring system and effectively manage the excellent forest wetlands. The survey investigated the area seasonally every 4-5 years from 2015 to 2021. The change of flora of 32 excellent forest wetlands in Jeollanam-do increased from 103 families, 311 genera, 496 species, 16 subspecies, 38 varieties, 6 varieties, 556 taxa, to 111 families, 362 genera, 599 species, 16 subspecies, 51 varieties, 8 varieties, 674 taxa. Remarkable plants such as Red list and plants endemic to the Korean Peninsula increased also. However, Nepeta cataria and the like are exterminated locally, so an in situ and ex situ conservation strategy must be established. In the case of plants categorized according to wetland preference, the distribution ratio of such wetland plants slightly decreased and the distribution ratio of such terrestrial plants lightly increased for absolute wetland plants. It is necessary to prepare countermeasures for the terrestrialization of forest wetlands and to develop research techniques that can distinguish boundaries. In addition, the forest wetland should be systematically managed and supervised by designating it as a Forest Genetic Resources Reserve that can effectively conserve it.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.108-118
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• 2021

The purpose of this study was to provide baseline ecological data for the conservation of the Manchurian trout habitat through the investigation of the growth status of Brachymystax lenok tsinlingensis, and Pearson's correlation analysis (PCA) between the B. lenok tsinlingensis population and the use of the land around Gyebangcheon stream. Sampling was conducted twice in July, September, and October 2018. During the July and September surveys, 882 individuals belonging to 13 species from six families were collected. The dominant species was Rhynchocypris kumgangensis and the subdominant species was Zacco koreanus. The total number of B. lenok tsinlingensis collected was 99. The results of the length-weight relationship in the B. lenok tsinlingensis population were analyzed with a regression coefficient b value of 3.1272 and a condition factor (k) value of 0.0006. Therefore, the growth condition of B. lenok tsinlingensis was regarded as fairly good. The QHEI(Qualitative habitat evaluation index) value in the B. lenok tsinlingensis habitat was 119.5(±0.5)-153.5(±0.5), indicating optimal-suboptimal conditions. As a result of the HIS (Habitat suitability index) analysis, it was confirmed that the optimal habitat for B. lenok tsinlingensis was 0.45-0.55m and >1 m in water depth, 0.55-0.65 m s^-1 in water velocity, and boulder in the substrate. The ratio of the land use in this study site was analyzed as 66.26-96.31% for forest and grassland areas, 0.00-23.79% for agricultural areas, 0.00-4.19% for urbanized areas, and 3.69-8.87% for others. Correlation analysis of the number of B. lenok tsinlingensis and various factors revealed statistically significant correlations between QHEI and forest and grassland areas, agricultural areas, and urbanized areas.