• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.4
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• pp.351-361
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• 2023

The purpose of this paper is to help those who research and develop solar cells in university laboratories and industrial sites understand the most basic and important quantum efficiency measurement and analysis method in analyzing solar cell performance. Starting with the definition of quantum efficiency, we calculate the theoretical current density according to the band gap of the solar cell material from the solar spectrum, along with a detailed introduction to the measurement and analysis methods, and measure and analyze the theoretical current density and quantum efficiency. We discuss in depth how to analyze the performance of solar cells through Quantum efficiency measurement and analysis of solar cells is a very useful method that can give intuition to solar cell performance analysis as it can analyze solar cells according to depth (front emitter, bulk, rear surface). Students and researchers who study solar cells with a deep understanding of theoretical current density and quantum efficiency measurement analysis are expected to use it as a basis for analyzing solar cell performance.

• Communications of Mathematical Education
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• v.37 no.1
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• pp.65-84
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• 2023

The method of Lagrange multipliers, one of the most fundamental algorithms for solving equality constrained optimization problems, has been widely used in basic mathematics for artificial intelligence (AI), linear algebra, optimization theory, and control theory. This method is an important tool that connects calculus and linear algebra. It is actively used in artificial intelligence algorithms including principal component analysis (PCA). Therefore, it is desired that instructors motivate students who first encounter this method in college calculus. In this paper, we provide an integrated perspective for instructors to teach the method of Lagrange multipliers effectively. First, we provide visualization materials and Python-based code, helping to understand the principle of this method. Second, we give a full explanation on the relation between Lagrange multiplier and eigenvalues of a matrix. Third, we give the proof of the first-order optimality condition, which is a fundamental of the method of Lagrange multipliers, and briefly introduce the generalized version of it in optimization. Finally, we give an example of PCA analysis on a real data. These materials can be utilized in class for teaching of the method of Lagrange multipliers.

• The Mathematical Education
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• v.61 no.2
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• pp.287-303
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• 2022

The purpose of this study is to draw implications for the improvement in the CSAT by analyzing structures and tasks in the Abitur. To this end, it analyzes the mathematics test system with a focus on the basic and advanced level examination systems, the operator, the using technology, and mathematical formulas. And the characteristics of tasks in the 2021 Abitur were analyzed. As a result of the analysis, first, Germany evaluates whether students have the competency emphasized in the curriculum at Abitur. Second, Germany, which emphasizes the proper use of technology, utilizes both tasks that use technology and those that do not in the Abitur. Third, the Abitur consists of most of the tasks using promised operators and uses various types of operators to present various types of questions to evaluate competence. Fourth, the Abitur includes not only simple structured items consisting of 2-3 subtasks but also tasks dealing in depth with a single situation centered on a big idea. Finally, mathematical justification and proof play an important role in the Abitur. Based on this, some specific measures for improving the CSAT were suggested.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.419-430
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• 2019

The study sought to find out the actual process of adapting to social life through interviews with college students and adult women living as defectors in the South, and to find out how it would be desirable to move forward in terms of education in order for all of our lives to be happy. The method of research consisted of semi-structured interviews. The interview period was four months. Based on the results of the interview, the following conclusions are given. First, it is necessary to establish a direction for strengthening cooperation rather than conflict in education, and restoring homogeneity of the same people. It is also true that real challenges are not easy at a time when the fratricidal war like the 6.25 conflict has deepened the conflict. However, at this point, 65 years later, the nation cannot stay only in the past. Second, the perception that they disapprove of economic aid to North Korean defectors also exists in part among adults. Third, negative thoughts about reunification among South Koreans also appear relatively high. This is believed to be due to the argument that the growth of social welfare and economic growth is offset by the increase in unification costs. Fourth, the content of living in real life such as culture and art, along with knowledge-oriented education in school education, should be treated with the same weight. This should create an environment in which North Korean defectors can enjoy the same happiness as South Koreans.

• The Korean Journal of Woman Psychology
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• v.14 no.2
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• pp.219-239
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• 2009

This study investigated gender differences in contribution of antisocial personality and affective empathy to psychopathy. Two hundred fifteen college students (male, 118; female,97) completed three measures including the PPI-R(Psychopathic Personality Inventory-Revised), the PAI-ANT(Personality Assessment Inventory-Antisocial Features), and the EETS (Emotional Empathy Tendency Scale). According to the results, the mean scores of PPI-R and EETS in male group were higher than in female group. Antisocial features were positively associated with psychopathy in both male and female groups and negatively with affective empathy. Males showed that the scores of affective empathy were negatively associated with those of antisocial features and psychopath. Females showed that the scores of affective empathy were negatively associated with those of antisocial personality and psychopathy but the correlation was significant only with the scores of antisocial behavior (ANT-A). To scrutinize the differences between male and female groups, the scores on the PAI and EETS were compared between 30% upper and 30% lower groups based on the scores of the PPI-R. According to the results, the upper group of the scores on the PPI had higher scores on the PAI and lower scores on the EETS. The differences of the scores on the EETS between high-psychopathy and low-Psychopathy groups were bigger in male group than in female group. Explanations and implications of the results were discussed and the directions of the future studies were suggested.

• Economic Analysis
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• v.25 no.4
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• pp.1-24
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• 2019

This study examines the labor market performance of graduates who had student loans. Compared to earlier studies, we extended analyses to all jobs that were experienced for more than 18 months after graduation. First, we found that students who had student loans earned 2.81% less at their first job compared to their counterparts without student loans. Second, the wage gap decreased over time, a reduction of 0.66%p due to labor market turnovers. Third, when we compared cumulated labor income, however, the amount for borrowers were continuously higher. This is because the job searching period of a borrower was shorter, despite relatively lower wages at the first job, and borrowers also made more frequent job turnovers, accompanying relatively more wage increases. These results suggest that the negative effects of college loans on earnings, reported in previous studies, may have exaggerated the negative impact to some extent of having loans. However, when we look at the quality of jobs beyond simply wages, the proportion of borrowers working at large companies as regular workers was consistently low. Given that job conditions at the earlier stages of one's career may lead to gaps over time, our findings call for more systematic investigations into the effects that student loans have on long-term labor performance.

• Korean Journal of Culture and Social Issue
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• v.19 no.1
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• pp.69-86
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• 2013

The recent findings proposed and found that people from Eastern cultures could experience strong cognitive dissonance only when certain conditions, such as other-related choices, normative attitudes, were fulfilled. Even though such interesting findings are intuitively convincing on the basis of common understanding of individualist and collectivist cultures, the psychological mechanisms underlying the cultural variations of cognitive dissonance remain untested. The present study examined the role of attitude importance in cognitive dissonance by using the free-choice paradigm. After completing a pretest of individualism-collectivism scales, 60 college students ranked their preference to 10 items of either beverage or traffic regulations twice. Between the two ranking tasks, they were asked to engage in behavioral selection among their 5^th and 6^th preferred items. They also rated the personal importance of the preference. The results showed that attitude importance was positively correlated with attitude change and it could play a major role in experiencing cognitive dissonance beyond cultural orientation and situational factors. The current findings were discussed in universality of cognitive dissonance across cultures.

• Asia Marketing Journal
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• v.13 no.3
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• pp.135-161
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• 2011

Social commerce is a more recent phenomenon and growing in number and size with the diffusion of social networking services. But it has not been studied as extensively. The purpose of this study is to investigate consumers' social commerce usage intention empirically. Using the theory of reasoned action suggested by Fishbein and Ajzen(1975), this study tests that perceived value created by social commerce affects social commerce usage intention. In this study, authors e identify to the conception of perceived value as a multidimensional construct, economic, psychology, and time value. This study is to analyze the effects of the value perceived by the consumer on attitude toward social commerce and the effects of the attitude and subjective norm on social commerce usage intention. Additionally, we examine the moderating role of coupon redemption effort in the relationship between attitude toward social commerce and usage intention. In order to evaluative the validity of the model, 258 questionnaires were collected from college students who frequently use SNS and accept new trend and technology using internet survey. All the instrument items used in this study were adapted from previous research and the data were analyzed using SPSS 18 and AMOS 7. This study proposed several hypotheses and conducted an experiment to test these hypotheses. Based on the data analysis results, it was found that economic and psychology value has significant effects on attitude toward the social commerce but time value had not the effect on attitude toward the social commerce. And the present study has also shown that both attitude toward the social commerce and subjective norm significantly influenced usage intention. This finding suggests that the theory of reasoned action effectively explains the social commerce usage intention. The result regarding the moderating effect of the coupon redemption effort has shown that the attitude toward social commerce and usage intention is moderated by consumer perception about coupon redemption.

• Asia Marketing Journal
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• v.10 no.4
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• pp.65-98
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• 2009

The present study purposed to examine empirically the effects of animosity against a product's country of origin on product evaluation, attitude and purchase intention. For this study, we conducted an experiment of 316 university students in the Metropolitan area. The results of this study suggest that the negative influence of animosity against the country-of-origin on attitude and purchase intention was higher for low-typicality products than for high-typicality ones. This result suggests that the negative influence of animosity against a specific country is not equal among all products from the country, but can vary among the products. For products manufactured in a country other than the country-of-origin, the negative influence of animosity against the country-of-origin did not decrease. This result means that, even for multinational products, animosity against the country-of-origin can have a negative influence on the consumers' response to the products. Based on major findings of this study, both academic and practical issues are discussed. Suggestions for future studies are provided.

• Korean Journal of Culture and Social Issue
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• v.22 no.3
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• pp.343-362
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• 2016

Despite recent social movements to protect homosexuals' rights in Korea, psychological research investigating attitudes toward homosexuals has been largely ignored. The present study examined Koreans' explicit and implicit attitudes toward homosexuals and how openness is related to them. College students (N = 56) responded to questionnaires assessing explicit attitudes toward homosexuals and openness, one of the five factors of personality. They then took an Implicit Association Test designed to assess implicit attitudes toward homosexuals. We found that participants in general had more negative explicit attitudes toward gay men than lesbians. Implicit prejudice against gay men was also higher than lesbians. There was no participant sex difference in implicit attitudes toward gay men. However, male participants had more negative implicit attitudes toward lesbians than female participants did; in fact, females' implicit attitudes toward lesbians were not biased. While openness was negatively related only to explicit prejudice, values, one of the facets of openness, was negatively related to both explicit and implicit prejudice. This was the first study in Korea that investigated both explicit and implicit attitudes toward gay men and lesbians.