• Journal of Korean Society on Water Environment
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• 제24권4호
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• pp.488-498
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• 2008

Soil and Water Assessment Tool (SWAT) model have been widely used in simulating hydrology and water quality analysis at watershed scale. The SWAT model extracts topographic feature using the Digital Elevation Model (DEM) for hydrology and pollutant generation and transportation within watershed. Use of various DEM cell size in the SWAT leads to different results in extracting topographic feature for each subwatershed. So, it is recommended that model users use very detailed spatial resolution DEM for accurate hydrology analysis and water quality simulation. However, use of high resolution DEM is sometimes difficult to obtain and not efficient because of computer processing capacity and model execution time. Thus, the SWAT Topographic Feature Extraction Error (STOPFEE) Fix module, which can extract topographic feature of high resolution DEM from low resolution and updates SWAT topographic feature automatically, was developed and evaluated in this study. The analysis of average slope vs. DEM cell size revealed that average slope of watershed increases with decrease in DEM cell size, finer resolution of DEM. This falsification of topographic feature with low resolution DEM affects soil erosion and sediment behaviors in the watershed. The annual average sediment for Soyanggang-dam watershed with DEM cell size of 20 m was compared with DEM cell size of 100 m. There was 83.8% difference in simulated sediment without STOPFEE module and 4.4% difference with STOPFEE module applied although the same model input data were used in SWAT run. For Imha-dam watershed, there was 43.4% differences without STOPFEE module and 0.3% difference with STOPFEE module. Thus, the STOPFEE topographic database for Soyanggang-dam watershed was applied for Chungju-dam watershed because its topographic features are similar to Soyanggang-dam watershed. Without the STOPFEE module, there was 98.7% difference in simulated sediment for Chungju-dam watershed for DEM cell size of both 20 m and 100 m. However there was 20.7% difference in simulated sediment with STOPFEE topographic database for Soyanggang-dam watershed. The application results of STOPFEE for three watersheds showed that the STOPFEE module developed in this study is an effective tool to extract topographic feature of high resolution DEM from low resolution DEM. With the STOPFEE module, low-capacity computer can be also used for accurate hydrology and sediment modeling for bigger size watershed with the SWAT. It is deemed that the STOPFEE module database needs to be extended for various watersheds in Korea for wide application and accurate SWAT runs with lower resolution DEM.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• 제9권3호
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• pp.123-129
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• 2009

Ubiquitous home is emerging as the future digital home environments that provide various ubiquitous home services like u-Life, u-Health, etc. It is composed of some home appliances and sensors which are connected through wired/wireless network. Ubiquitous home services become aware of user's context with the information gathered from sensors and make home appliances adapt to the current home situation for maximizing user convenience. In these context-aware home environments, it is the one of significant research topics to predict user behaviors in order to proactively control the home environment. In this paper, we propose Multi-Level prediction algorithm for context-aware services in ubiquitous home environment. The algorithm has two phases, prediction and execution. In the first prediction phase, the next location of user is predicted using tree algorithm with information on users, time, location, devices. In the second execution phase, our table matching method decides home appliances to run according to the prediction, device's location, and user requirement. Since usually home appliances operate together rather than separately, our approach introduces the concept of mode service, so that it is possible to control multiple devices as well as a single one. We also devised some scenarios for the conceptual verification and validated our algorithm through simulations.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제26권5호
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• pp.385-392
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• 2013

The finite element method has become the most widely used method of structural analysis and recently, the method has often been applied to complex dynamic and nonlinear structural analyses problems. Even for these complex problems, where the responses are hard to predict, finite element analyses yield reliable results if appropriate element types and meshes are used. However, the dynamic and nonlinear behaviors of a structure often include large deformations in various portions of the structure and if the same mesh is used throughout the analysis, some elements may deform to shapes beyond the reliable limits; thus dynamically adapting finite element meshes are needed in order for the finite element analyses to be accurate. In addition, to satisfy the users requirement of quick real run time of finite element programs, the algorithms must be computationally efficient. This paper presents an adaptive finite element mesh generation scheme for dynamic analyses of structures that may adapt at each time step. Representative strain values are used for error estimates and combinations of the h-method(node movement) and the r-method(element division) are used for mesh refinements. A coefficient that depends on the shape of an element is used to limit overly distorted elements. A simple frame example shows the accuracy and computational efficiency of the scheme. The aim of the study is to outline the adaptive scheme and to demonstrate the potential use in general finite element analyses of dynamic and nonlinear structural problems commonly encountered.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• 제34권2호
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• pp.35-44
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• 2016

This study targets flower-viewing sites appearing in "Kyungdojapji" and talks about the seasonal customs and tourist attractions of the later Chosun; Pilundae, Bukdun, Outside of Dongdaemun, Cheonyunjeong and near Seodaemun etc. Through related poetry, paintings and maps, it looks into what scenic elements each attraction was made of and how the elements were felt by visitors. It sub-divided and analyzed scenic features into objective objects, subjective emotions and experienced behaviors. As a result, representative objective objects were flowers and there were also scenes where people enjoyed poem-writing meetings along with drinking-related physical elements such as liquor, liquor glasses, liquor bottles etc. Through drawing out scenes, where users gave meaning to objective objects, it tried to interpret what space meant to them, through which the meaning of flower-viewing attractions is first and foremost a space to enjoy artistic taste. Each space is used as the center of cultural creation such as literary people gathering, viewing flowers, drinking and having poetry-writing meetings. Second, as shown in scenes viewers depicted in each space, visitors were confirmed to enjoy scenes through multi-sensory appreciation. By this, flower-viewing attractions were confirmed to be not just flower-viewing but also venues of sensory experience. This study, which drew out the scenic features of traditional flower-viewing attractions, is expected to be basic material in tracing the flower-viewing enjoyed by our ancestors as a pastime and its spatial meaning and in planning Korea-unique flower-viewing attractions.

• Asia pacific journal of information systems
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• 제19권4호
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• pp.149-176
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• 2009

In the recent e-learning environment, avatars are often used to help learners get familiar with the contents, which is ultimately to motivate them to study more. Therefore, it is important to investigate whether avatars have actually the desirable effect on users of e-learning materials. Surprisingly, however, no extensive study has been conducted on this crucial issue Accordingly, main objectives this study are summarized as follows. First, we need to gain better understanding of how much learners' trust towards avatars (termed as "avatar trust") is transferred to learners' trust towards e-learning contents (termed as "contents trust"). Second, we need to investigate how much learners' personal relationships with avatars as well as learning behaviors change depending on avatar types (attractive vs. professional) and contents complexity (easy vs. difficult). As described in the study objectives, in order for us to analyze empirical data more systematically, we classified avatar types into two: "attractive" and "professional;" the contents are categorized as either "easy" or "difficult." Therefore, it is essential for this study to build a prototype e-learning website on which our research purpose can be realized and tested effectively with proper avatar types and e-learning contents. For this purpose, we built a prototype e-learning website, in which avatars are invited from currently working avatar instructors used in real-world e-learning websites, and e-learning contents are adapted from real-world contents about Java programming topic, which have been proved to have shown high quality and reliability. Our research method includes questionnaire survey by inviting a number of valid respondents comprised of office workers who are believed to have high demands for the e-learning contents as well as those who have previous experience with avatar instructors. Respondents were given one of the four e-learning experiment conditions (2 avatar types x 2 contents types) on a random basis. Each experimental e-learning condition is framed to have the same quality but different avatar type and content complexity. Then the respondents are asked to fill out the survey form which has questions about avatar trust, contents trust, personal relationships with avatar, and learning behavior, among others. Regarding the constructs used in research model, we based them rigorously on previous studies. For example, we used six constructs such as behavior to give information (BGI), behavior to obtain information (BOI), need for inclusion wanted, need for control wanted, contents trust, and avatar trust. To measure them, 7-Likert scales were used in the questionnaire. E-learning performance was measured indirectly through two constructs such as BGI and BOI. Six constructs used in the research model were adopted and revised from the FIRO-B model suggested by Schutz. Empirical results are as follows: First, professional avatars are more effective for difficult contents, while attractive avatars were not as effective for easy contents. Second, our study results ascertained that avatar trust transfers to contents trust regardless of avatar types and contents complexity.

• Journal of Korea Port Economic Association
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• 제34권4호
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• pp.161-180
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• 2018

Environmental value is essential to the survival and development of humans. Environmental value and its importance are being emphasized, and related disputes are being expanded. The concept of green logistics is understood to be the same as that of the environment. As a way to preserve nature and engage in sustainable development, green logistics includes all logistical activities for protecting nature and minimizing or reducing behaviors that harm the environment for all processes, including using and reusing products and abolishing the search for resources by final users. All areas of human activity, such as the political, economic, social, and cultural sectors, strive to protect and preserve the environment and nature. In particular, the preservation of the environment shall be stressed in the economic activities that produce various products and expand the value added, and similarly for the social aspects. Green (environment) logistics aims to protect the environment and expand the prevention of environmental destruction and minimization on Earth. Some important cases and experiences that were introduced and applied in major countries are summarized. This research reviewed previous studies and the concepts of green logistics, including at ports, which represent a key sector of logistical activities. In this paper, air and water pollution at Incheon Port were investigated, and alternatives and system figures related to improving environmental logistics regarding three dimensions-country, company, and civil society-are recommended.

• Korea journal of population studies
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• 제11권1호
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• pp.14-31
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• 1988

The national family planning program in Korea, which was instituted as an integral part of the nation's economic development plans since 1962, has contributed greatly to a reduction in the fertility and population growth rate. The total fertility rate dipped from 6.0 births per women in 1960 to 2.0 in 1985, and the population growth rate rom 2.84 percent per year to 1.25 percent during the same period, while the contraceptive practice rate for the 15-44 married women increased from 9 percent in 1965 to 70 percent in 1985. Study findings indicate that the fertility reduction in the past 26 years is largely attributed to the virgorous implementation of the national family planning program, rising age at marriage, wide-spread use of induced abortion, and the changes in attitude regarding the value of children that came into being in the wake of the rapid socio-economic development over the period. Among the strengths of the national family planning program are the following : 1) a pluralistic system of program manageent with active participation of various government and voluntary organizations, 2) utilization of a large corps of family planning field workers to conduct face-to-face communication and motivation activities, 3) use of private physicians with government support to provide contraceptive services, 4) a systematic program management system including program planning of traget allocation, evaluation, and supervision with a broad MIS and award system, 5) numerous incentive and disincentive schemes for stimulating the small family norm and contraceptive use, and 6) strong commitments to the family planning program by political leaders. The new demographic targets during the Sixth Five-Year Economic and Social Development plan period(1987-91) have been set for a further reduction in the population growth rate to 1.0 percent by 1993, assuming that the TFR will decline to 1.75 level in 1995. This target is, however, not easy to achieve due to anticipated unfavorable factors like the strong boy preference, high discontinuation rates of reversible contraceptive methods, fertility termination-oriented contraceptive use, a plateau level of contraceptive practice rate that has mostly accounted for a sterilization, shortened length of birth intervals, and the changing patterns of contraceptive mix. The recent changes in contraceptive and fertility behaviors clearly indicate that the past quantity-oriented management system of the national program should be redirected toward a quality-oriented approach. Particularly, program efforts should be expanded to recruit new contraceptive users in the 20s of younger age groups, both for birth spacing and controlling their fertility since the women aged 20 to 29 account for more than 80 percent of the total annual births in recent years. In addition, the current contraceptive fee system of the national family planning program should be gradually shifted from free contraceptive services to a acceptor's charge system, and the provision of contraceptive services through the medical insurance system, which will cover the entire population by 1989, should be accelerated as a means of integration of family planning program with other health programs.

• Journal of the Korean Society for Library and Information Science
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• 제55권4호
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• pp.187-217
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• 2021

This study investigated the perceptions of librarians about Podcast and YouTube services in libraries. The study was designed by applying the Extended Technology Acceptance Model. Librarian's personal, organizational, and social awareness of library Podcast or YouTube services and the degree of understanding of users and their needs on services were mediated by perceived usefulness or ease of services= and influenced to having intentions and providing the services. First, we investigated the types of Podcast and YouTueb services provided by 39 libraries in Korea. Also, we collected data using an online survey method from 181 librarians and conducted hierarchical multiple regression analysis. Findings showed that libraries are using Podcast and YouTube appropriately considering features and functions of media, mainly for library event information/promotion, library programs, book recommendations, and author (librarian) lectures or interviews. Organizational or social awareness of librarians, i.e., library educational support, human resource supports, librarian recognition, job-related features, and understanding of user perceptions and needs, influenced the intention to provide library services. Also, there was a difference in perceived usefulness and ease of services between librarians who provided Podcast and YouTube services and those who did not. We expect that findings could be used as references to understand and support various aspects of librarians in charge of developing and providing Podcast or YouTube services in libraries.

• 한국노년학
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• 제37권3호
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• pp.583-600
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• 2017

The purpose of this study is to explore qualitatively what kind of coping strategy the Korean older adults use when they are depressed and why. Participants were users, older than 60, of an elderly welfare center in Seoul, and answers of 34 respondents who experienced depression were included in the analysis. The collected data were analyzed through content analysis. The results of the analysis showed that strategies to cope with depression used by participants were composed of 6 domains and 11 sub-domains: health behavior (medical approach / exercise and diet), family and social contact (social interaction / going out and going on a trip / communication with family), Religious activities (Religious activities), lifelong education (hobbies / educational activities), productive activities (labor), health risk behaviors (drinking and gambling / resignation). The depression coping strategies of the older adults and their characteristics are as follows. First, older adults used diverse problem-focused coping strategies to cope with depression. Second, older adults considered various coping strategies together and used them simultaneously. Third, the facility space for older adults functions as a shelter. Fourth, although there were cases where medical approach was used, the intention to reuse was very low. Through this study, the following suggestions were made to help older adults cope with depression more successfully. First, access to various coping strategies should be promoted. Second, more places where older adults can spend their time comfortably need to be provided. Third, resistance to mental health care should be resolved.

• Journal of Environmental Health Sciences
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• 제46권6호
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• pp.750-756
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• 2020

Objectives: After coronavirus disease 2019 (COVID-19) was declared a pandemic, the South Korean government announced guidelines on wearing masks to prevent its spread. The guidelines have changed depending on the severity of the spread of COVID-19. This study aimed to identify mask-wearing behaviours to counter the spread of COVID-19 in indoor and outdoor environments. Methods: The type of mask worn and proper wearing were observed in cafés, supermarkets, underground shopping malls, and streets in Seoul. Behavioral assessment was repeated in August at social distancing levels 1 and 2, in October at social distancing level 1, and in November after the mask mandates. Results: In August, 22.1% of subjects in cafés, 90.8% in supermarkets, 91.8% in underground shopping malls, and 83.6% on outdoor streets wore masks properly. In October, the proportion of correct wearers increased in all locations. After masks became mandatory in November, about 97% of users of supermarkets, underground shopping malls, and streets wore masks properly. In cafés, the proportion of proper wearers was 61.5% with both social distancing level 2 in August and the mandate in November. The number of KF-certified mask wearers continued to increase from August to November. Conclusion: This study investigated mask-wearing behaviors to counter COVID-19 through observations in indoor and outdoor places in Seoul. Mask-wearing behavior was different depending on the place and the government guidelines in place. The results could be used for evaluation of the current guidelines for COVID-19.