• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.395-400
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• 2001

In construction projects, it is very important to evaluate the performance of works in comparison with the cost and schedule plans. So, on the first of July, 2000, the Ministry of Construction and Transportation announced the EVMS will be applied in public sector soon. However there are still many arguments about how to establish the Performance Measurement Baseline(PMB) and how to evaluate the progress with accuracy. And many people confuse the meaning of EVMS with that of cost and schedule management. So, the purpose of this research is to propose the new useful methods to set up the PMB and to assess the exact progress in consideration of cost, schedule, and float time for successful implementation of EVMS.

• Journal of Venture Innovation
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• v.5 no.2
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• pp.101-110
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• 2022

It is easy for first movers of platform business model to monopolize the market due to the platform's own characteristics such as network effect and flywheel strategy. Accordingly, the regulations on platform operators are constantly being discussed in the recent monopoly regulation arguments, but the concrete regulations have not been settled worldwide. This is because there is no clear consensus on the valuation method which can objectively identify dominant platform firms from the others. This study suggested a platform valuation method based on the Tobin's Q theory, by measuring the moderating effect of the existence of specific scale of platform on the relationship between replacement cost and market valuation. Our method can not only be a standard for settling monopoly regulation by converging the regulation targets, but also contribute to active investment on the new platform firms by evaluating their potential growths quantitatively.

• Journal of The Korean Association For Science Education
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• v.23 no.3
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• pp.215-228
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• 2003

The present study is to analyze the arguments about the generation of declarative scientific-knowledge in the philosophy of science and invent a structured model of the process of scientific-knowledge generation with the types of the generated scientific-knowledge. The invented model shows that scientific-knowledge generation is a distinctive process with the processes of inductive, abductive, and deductive thinking. Furthermore, inductive process is included with observation, which is consisted of simple observation and operative observation, and rule-discovery which is involved with the processes of commonness discovery, classification, pattern discovery, and hierarchical relationship. Also, abductive process has two components. One component generates question and second component generates hypothesis in which the process consists of representing question situation, identifying experienced situation, identifying causal explicans, and generating hypothetical explicans. Finally, deductive process is involved with logical inventing test method and evaluation criteria, concrete inventing test method and evaluation criteria, evaluating hypothesis, and making conclusion.

• Journal of The Korean Association For Science Education
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• v.35 no.6
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• pp.1019-1030
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• 2015

This study examined the development of a teacher's teaching practice and identified argumentation-specific pedagogical content knowledge (PCK) and the influence of the argumentation-specific PCK on teaching practice in an argumentation classroom. The teacher has a Ph.D degree in science education, a 19-year teaching career, and no experience in instructing in an argumentation classroom. The developed program consists of nine lessons regarding photosynthesis for 7th graders. The teacher participated in a collaborative reflection with researchers after each lesson once a week and five times in total, which lasted for thirty minutes. All of the lessons were video- and audio-recorded and the transcript of lessons and collaborative reflection, pre- and post-survey related to argumentation, and researchers' journals were analyzed. Analysis of the data showed that the teacher emphasized group interaction showing utterances of listening, evaluating arguments, counter-arguing/debating, and reflecting on argument process after the fourth lesson although the teacher focused on individual argumentation showing utterances of talking, knowing meaning of argument, and justifying with evidence in the first three lessons. Also, the argumentation-specific PCK, which was identified with the understanding of students, nature of argumentation and argumentation task strategy, also influenced the development of teaching practice. The teacher comprehended the students' challenges in argumentation, developed her understanding of the nature of argumentation from an individual plane to social plane, and demonstrated a deep understanding of the task strategy by voluntarily joining in modifying the argumentation tasks.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.515-521
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• 2007

Aprotinin, a serine protease inhibitor, has been used to ameliorate the inevitable consequences, including blood component injury after cardiac surgery with cardiopulmonary bypass (CPB). However, there are many arguments on its dosage or usage. We assessed whether administration of low dose of aprotinin in only priming solution has any beneficial effect or reduces its side effects on cardiac surgery. Thirty patients scheduled for elective cardiac surgery were randomly assigned to aprotinin group (n=15) which received aprotinin in priming solution (two million kallikrein inhibitory unit, KIU) and added one million KIU at 1 hour after the beginning of CPB or control group (n=15) which did not receive it. Hematological and biochemical variables, cytokines and cardiac marker levels, and postoperative outcomes were compared between two groups at before, during or after operation. Platelet count in aprotinin group was higher than that of control group at postoperative 24 hr. Activated partial thromboplastin time in aprotinin group was longer than that of control group at intensive care unit (ICU). Troponin-I level and postoperative blood loss volumes in aprotinin group were lower than those of control group at ICU. There were no significant differences between the two groups on the others. These results showed that low dosage of only priming solution during cardiac surgery with CPB reduced platelet destruction and postoperative bleeding, and attenuates myocardial damage. However, further studies need to be carried out with more population or pediatric patients for evaluating various aprotinin usage.

• Journal of The Korean Association For Science Education
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• v.41 no.5
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• pp.401-414
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• 2021

The purpose of this study is to explore the cognitive achievement characteristics by group of achievement levels in the PISA 2018 science domain compared to the results of the PISA 2015, and to compare and analyze the 'epistemic' knowledge in the revised curriculum 2009 and in the revised curriculum 2007. The average correctness rates in PISA 2015 and PISA 2018 were analyzed by sub category of the evaluation frame in the PISA scientific domain. In the competencies domain, especially, the average correct answer rates of 'evaluating and designing scientific inquiry' were the lowest in medium and lower groups, but the rates rose in all achievement groups compared to PISA 2015, which is encouraging. Although the answer rates were low for both 'living system' knowledge and 'epistemic' knowledge in the knowledge domain, the average answer rates of the upper and middle groups increased in 'epistemic' knowledge compared to PISA 2015. The changes in the curriculum experienced by students participating in PISA were analyzed in relation to the 'evaluating and designing scientific inquiry' competency and 'epistemic' knowledge, which increased in average correct answer rates. In terms of understanding science, the "What is science?" unit that explicitly presents epistemic knowledge, and nature of model in inquiry activities, were explicitly presented in the revised curriculum 2009. In terms of understanding the process of justifying scientific knowledge, the number of inquiry activities increased, scientific explanations based on experimental results strengthened, and the "Science and Human Civilization" unit was introduced to help students to understand STS while simultaneously conducting arguments. These findings confirm the educational performance of groups by achievement level in the PISA 2018 scientific domain and suggest that the direction of education relates to epistemic knowledge in Korea's Science curriculum.

• Asia pacific journal of information systems
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• v.24 no.4
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• pp.559-575
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• 2014

Individual investors are increasingly flocking to message boards to seek, clarify, and exchange information. Businesses like Seekingalpha.com and business magazines like Fortune are evaluating, synthesizing, and reporting the comments made on message boards or blogs. In March of 2012, Yahoo! Finance Message Boards recorded 45 million unique visitors per month followed by AOL Money and Finance (19.8 million), and Google Finance (1.6 million) [McIntyre, 2012]. Previous studies in the finance literature suggest that online communities often provide more accurate information than analyst forecasts [Bagnoli et al., 1999; Clarkson et al., 2006]. Some studies empirically show that the volume of posts in online communities have a positive relationship with market activities (e.g., trading volumes) [Antweiler and Frank, 2004; Bagnoli et al., 1999; Das and Chen, 2007; Tumarkin and Whitelaw, 2001]. The findings indicate that information in online communities does impact investors' investment decisions and trading behaviors. However, research explicating the correlation between information on online communities and stock market activities (e.g., trading volume) is still evolving. Thus, it is important to ask whether a volume of posts on online communities influences trading volumes and whether trading volumes also influence these communities. Online stock message boards offer two different types of information, which can be explained using an economic and a psychological perspective. From a purely economic perspective, one would expect that stock message boards would have a beneficial effect, since they provide timely information at a much lower cost [Bagnoli et al., 1999; Clarkson et al., 2006; Birchler and Butler, 2007]. This indicates that information in stock message boards may provide valuable information investors can use to predict stock market activities and thus may use to make better investment decisions. On the other hand, psychological studies have shown that stock message boards may not necessarily make investors more informed. The related literature argues that confirmation bias causes investors to seek other investors with the same opinions on these stock message boards [Chen and Gu, 2009; Park et al., 2013]. For example, investors may want to share their painful investment experiences with others on stock message boards and are relieved to find they are not alone. In this case, the information on these stock message boards mainly reflects past experience or past information and not valuable and predictable information for market activities. This study thus investigates the two roles of stock message boards-providing valuable information to make future investment decisions or sharing past experiences that reflect mainly investors' painful or boastful stories. If stock message boards do provide valuable information for stock investment decisions, then investors will use this information and thereby influence stock market activities (e.g., trading volume). On the contrary, if investors made investment decisions and visit stock message boards later, they will mainly share their past experiences with others. In this case, past activities in the stock market will influence the stock message boards. These arguments indicate that there is a correlation between information posted on stock message boards and stock market activities. The previous literature has examined the impact of stock sentiments or the number of posts on stock market activities (e.g., trading volume, volatility, stock prices). However, the studies related to stock sentiments found it difficult to obtain significant results. It is not easy to identify useful information among the millions of posts, many of which can be just noise. As a result, the overall sentiments of stock message boards often carry little information for future stock movements [Das and Chen, 2001; Antweiler and Frank, 2004]. This study notes that as a dependent variable, trading volume is more reliable for capturing the effect of stock message board activities. The finance literature argues that trading volume is an indicator of stock price movements [Das et al., 2005; Das and Chen, 2007]. In this regard, this study investigates the correlation between a number of posts (information on stock message boards) and trading volume (stock market activity). We collected about 100,000 messages of 40 companies at KOSPI (Korea Composite Stock Price Index) from Paxnet, the most popular Korean online stock message board. The messages we collected were divided into in-trading and after-trading hours to examine the correlation between the numbers of posts and trading volumes in detail. Also we collected the volume of the stock of the 40 companies. The vector regression analysis and the granger causality test, 3SLS analysis were performed on our panel data sets. We found that the number of posts on online stock message boards is positively related to prior stock trade volume. Also, we found that the impact of the number of posts on stock trading volumes is not statistically significant. Also, we empirically showed the correlation between stock trading volumes and the number of posts on stock message boards. The results of this study contribute to the IS and finance literature in that we identified online stock message board's two roles. Also, this study suggests that stock trading managers should carefully monitor information on stock message boards to understand stock market activities in advance.