• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.23-32
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• 2019

In this paper, we proposed a multi-chain Time of Arrival (ToA) positioning method to estimate positions using all received Loran-C signals from multiple chains without constraining to a single chain. Conventionally, we have to choose only one chain among several available chains for position estimation using Loran-C. Therefore, the number of signals to be used for positioning is limited to three to five. In general, if more signals are used for positioning estimation, its performance tends to be improved in terms of accuracy and availability. To validate the proposed method for multi-chain Loran-C, we firstly carried out a static positioning test in land. By analyzing the test results, we confirmed that the proposed method works well under a multi-chain Loran-C scenario. Subsequently, another mobile positioning test was conducted on board a vessel under a practical application scenario. From this second test, we successfully demonstrated that the multi-chain ToA positioning method even in situations where the conventional single-chain Loran-C approach fails for positioning.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.170-186
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• 2019

The marine ecosystem survey investigates and analyzes multi-parameters at various times from various sites. Therefore, it is very difficult to analyze the complex ecological data of multi-items effectively, and it is more difficult to identify the current status and diagnose the problems of ecosystem through data analysis. Therefore, this paper aims to provide an example of interpretation of complex ecological data through analysis of distribution characteristics and outliers of ecological survey data. The main contents of the study are to elucidate the background levels of coastal ecosystem parameters considering the distribution characteristics of data, and to establish ecosystem monitoring indicators and an adaptive management system for the coastal waters in Korean Peninsula. The data used in this paper are based on the coastal ecosystem survey of the National Marine Ecosystem Monitoring Program conducted by the Ministry of Oceans and Fisheries (MOF) and the Korea Marine Environment Management Corporation (KOEM), and the major citations are from year 2015 to 2017. This article is a preliminary study to establish the above processes and the final result will be derived in 2020 when the coastal ecosystem survey is completed three times along the Korean coast.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.173-186
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• 2019

The purpose of this study is to design and apply a pilot inquiry experiment focusing on the epistemological issues of scientific activities, and derive educational implications by analyzing experimental activities and reflective discussions. Three graduate students who major in science education participated in the study voluntarily. Participants showed the characteristics of stable enquiry in Experiment 1. However, the small but continuous changes in Experiment 2 led the experiment to a phase of fluid enquiry seeking new theories. Participants mobilized various resources, proposed new hypotheses, and models and requested additional experiments to verify them. In the process of reflective discussions, the participants led to the following three epistemological issues. First, at the beginning of the experiment, their observations were theoretically dependent. Second, when the observations were no longer coherent with theory, they face a crisis, and the adjustment of observation and theory proceeds. Third, stable enquiry and fluid enquiry are performed according to the relationship between observation and theory. The educational implications of school science inquiry based on the above process and results are as follows: First, this study shows that fluid enquiry can follow stable enquiry naturally, and examples of the activities are presented together. Second, in this study, it was confirmed that participants could draw up epistemological issues based on their experiences through reflective discussions following inquiry.

• Journal of The Korean Association of Information Education
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• v.23 no.2
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• pp.131-139
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• 2019

From 2019, software education has become a required subject for all elementary school students. However, many teachers are still unfamiliar with how the classes should be instructed. So this paper presented the meaning, detailed competencies and achievement standard in order to help in the collection, analysis and representation of data among the computational thinking that are key to software education. And it also suggested the applicability of the classes. The full course of the paper is summarized as follows. First, existing studies have summarized the meaning, detail and achievement standard of data related competencies. Based on this, a preliminary investigation was instructed. Pilot study carried out both FGI and closed questions at the same time. This was done in response to the survey's questionnaire reflecting the opinions of experts. Second, the results of the questionnaire generated as a result of the above were verified for validity, stability, and reliability among the PhD, PhD courses, software education teachers, and software education workers. Third, I developed and applied the five lessons as a class objective as 'Choosing collection method-Select the collection method according to the problem situation.', 'Searching for meaning of data-Understand what the analyzed data mean..', 'Using various expression methods-Use a variety of expression tools.' using the backward design model to integrate education, class, and assessment. As a result, the detailed competencies of data collection, analysis, and representation and achievement standard were presented. This may help in setting specific and specific criteria for what direction classes are recommended when planning data-related classes in elementary schools.

• Journal of Digital Convergence
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• v.17 no.4
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• pp.279-284
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• 2019

The purpose of this study is to investigate the direction of communication design through in-depth interviews on the topic of gender equality, which is an active theme of social issue happening worldwide, and to suggest a direction to provide better social issue communication direction. In order to do so, firstly, I researched case studies and investigated the characteristics of gender magazines such as If, Ferm and Womankind. Secondly, I conducted an empirical study of in-depth interviews to identify the emotional adjectives by women and men by different age groups from gender equality storytelling magazine experience. As a result, I was able to grasp two points necessary. First of all, for the gender equality content messages closely related to everyday stories level down the barrier and become easier to empathize with. Second of all, the more complex the social issues are, the more sustainable and credible if the content developed steadily and contingently. This study is meaningful in that it suggested a series of directions for communicating gender equality issues. Future research should complement the suggested directions for gender equality communication design and contribute to guiding further directions.

• Journal of Conservation Science
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• v.37 no.2
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• pp.167-178
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• 2021

For the preservation and efficient content sharing of 5 volumes (2,866 pages) of Yu Kil-Chun's book published in 1971, which provides an important collection of data for the study of modern Korean history during the late 19th century (enlightenment period of Joseon dynasty). The books were purchased and its preservation status investigated and documented electronically by scanning for permanent preservation of content and to determine the condition of preservation at the time of documentation. The degree of deterioration and damage, such as discoloration, hardening, breakage, and damage in these 50 years old modern printed books was quantified through image analysis and made attempts to visualize the damaged areas. It was observed that the degree of deterioration and damage depended on the material and the surface condition of the paper used, the degree of exposure to light, and the storage environment. The comparison of the preservation status at the time of the photographing (or scanning) and judgment as to whether or not the image under investigation was artificially modified was accomplished by comparing the electronically documented images of Seoyugyeonmun (西遊見聞) in Volume 1 of Yu Kil-Chun's works with images provided on other websites. Practical problems encountered while considering the effective preservation of electronically documented data and publicly sharing it, in the course of this study, with other academic researchers around the world were also summarized.

• Science of Emotion and Sensibility
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• v.24 no.1
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• pp.59-72
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• 2021

Concepts and categories offer the basis for inference pertaining to unobserved features. Prior research on category-based induction that used blank properties has suggested that similarity between categories and features explains feature inference (Rips, 1975; Osherson et al., 1990). However, it was shown by later research that prior knowledge had a large influence on category-based inference and cases were reported where similarity effects completely disappeared. Thus, this study tested category-based feature inference when features are connected in a causal chain and proposed a feature inference model that predicts participants' inference ratings. Each participant learned a category with four features connected in a causal chain and then performed feature inference tasks for an unobserved feature in various exemplars of the category. The results revealed nonindependence, that is, the features not only linked directly to the target feature but also to those screened-off by other feature nodes and affected feature inference (a violation of the causal Markov condition). Feature inference model of causal model theory (Sloman, 2005) explained nonindependence by predicting the effects of directly linked features and indirectly related features. Indirect features equally affected participants' inference regardless of causal distance, and the model predicted smaller effects regarding causally distant features.

• Science of Emotion and Sensibility
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• v.24 no.3
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• pp.27-40
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• 2021

Because of self-enhancement motives, when involved in social comparison, many people generally value things that are related to themselves, with the representative example being possessions, which is known as the endowment (ownership) effect. However, there are times when someone else's possessions appear to be better than our own, even if they are the same things, which is known as the endowment effect reversal. The purpose of this study was to explore the moderating variable that regulates the endowment effect and the endowment effect reversal by confirming whether the value estimation of others' belongings differed through a regulatory focus as it was surmised that the regulatory focus would moderate the endowment effect of the self versus the others' ownership. Foreign participants were shown the currency of a country they were unfamiliar with and asked to estimate the value in their home country currency. It was found that when people thought the money was their own, people with a promotion focus estimated the value to be higher than people with a prevention focus. However, when they thought it was someone else's money, the regulatory focus moderating effect was not found to be significant, which suggested that the endowment effect may be strengthened or eliminated depending on the individual's regulatory focus. Based on these study results, the implications, limitations, and suggestions for follow-up studies are discussed.

• Journal of Science Education
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• v.44 no.3
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• pp.289-299
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• 2020

In this study, the definition, the level of difficulty, and the certainty of the understanding of 113 astronomy terminologies from 2009 revised middle school geoscience textbooks were examined. And through further interviews, the types of students' misconceptions about astronomy terminologies and their representative terms - examples of misconceptions were analyzed. The definitions of the terms presented by the students were largely classified as correct, low-level, and incorrect understanding. And low-level understanding was subdivided into high-level definition descriptions, undifferentiated concepts, and incorrect answers were subdivided into interference by scientific misconception and lack of prior knowledge. Given that the misconceptions due to terminologies can be distinguished from the prior misconception, the misconceptions due to terminologies can be effectively prevented by changing the term itself. In addition, students were aware of the advantages and disadvantages of metaphorical terms, and the recognition of their level of understanding is expected to be a good starting point considering that recognizing their own misconceptions is the first step in correcting them. Terminologies in science education is always an important subject of discussions, striving to select the right term according to the times, and scientific terms may change. It is expected that the results of this study will be the basis for discussions on the modification of terms.

• Korean Journal of Cognitive Science
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• v.32 no.2
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• pp.55-73
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• 2021

Psychological essentialism states that people believe some categories to have hidden and defining essential features which cause other features of the category (Gelman, 2003; Hirschfeld, 1996; Medin & Ortony, 1989). Essentialist belief on categories questions the Roschian argument (Rosch, 1973, 1978) that categories merely consist of clusters of correlated features. Unlike family resemblance categories, essentialized categories are likely to have clear between-category boundaries and high within-category coherence (Gelman, 2003; Prentice & Miller, 2007). Two experiments were conducted to test the effects of essentialist belief on category representation (i.e., between-category boundary, within-category coherence). Participants learned family resemblance and essentialized categories in their assigned conditions and then performed categorization task (Expt. 1) and frequency estimation task of category exemplars (Expt. 2). The results showed, in essentialized categories, both boundary intensification and greater category coherence. Theses results are likely to have arisen due to increased cue and category validity in essentialized categories and suggest that essentialist belief influences macroscopic representation of category structure.