• Journal of the Korean Geosynthetics Society
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• v.21 no.1
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• pp.1-10
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• 2022

In this study, a model parameter evaluation method using relative density was proposed to utilize applicable UBC3D-PLM for liquefaction behavior. In addition, dynamic effective stress analysis, that is, liquefaction analysis, was performed on the case of the liquefaction occurrence region where acceleration and pore water pressure were measured, and compared with the actual measurement and the existing Finn analysis results. Through this study, it was found that the proposed method can easily evaluate the necessary parameters required by the related model and predict the pore water pressure behavior in the region where liquefaction occurs. In addition, in the case of the study area, both measurements and numerical analysis showed that liquefaction occurred when a certain amount of time elapsed after the earthquake acceleration reached the maximum value. In the case of UBC3D-PLM applied in this study, the excess pore water pressure behavior similar to the actual measurement was predicted, and the occurrence of liquefaction was evaluated in the same way as the actual measurement. In particular, although the excess pore water pressure in the sand layer was greater, the phenomenon in which liquefaction occurred in the silt layer was accurately realized. It is expected that the proposed model parameter evaluation method and finite element analysis applying UBC3D-PLM can be used to select the liquefaction reinforcement region in the future seismic design and reinforcement by evaluating the liquefaction occurrence region similarly to the real one.

• Korean Business Review
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• v.11
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• pp.241-253
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• 1998

One form of the anomalies of stock price changes as reaction to earnings information is believed to be caused by the so-called earnings fixation, which is the overreaction of stock prices to earnings. According to the Sloan (1996) study, stock price changes are positively associated with earnings at the time of earnings releases, but the association becomes negative after that, as the early overreaction is corrected. However, the problem in his study is to use cash flows computed by adjusting earnings with appropriate income statement and balance sheet items. As Bahnson et al. (1996) show, these cash flows substantially deviate from SFAS No. 95 cash flows and the sample used in this study is found to be subject to this substantial measurement error. Therefore, the result of Sloan might be driven by this error and the reexamination of earnings fixation is warranted. The results are generally consistent with those in Sloan. First, earnings is positively associated with stock price changes at the time of earnings releases, but the association becomes negative after that. Second, cash flows show a weak association with stock price changes at the time of earnings releases, but the association become stronger thereafter. Third, when seperated from cash flows, accruals have an incremental explanation about stock price changes beyond that of cash flows, accruals have a negative association later on. This finding is consistent with stock price overreaction to accruals, even when more cleaner cash flow data are used.

• Korean Journal of Psychosomatic Medicine
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• v.23 no.1
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• pp.3-11
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• 2015

Objectives:To determine the influence of parental behaviors on the onset and severity of eating disorders, this study compared aspects of perceived parental styles, according to eating disorder subtypes and age at onset in Korean women with eating disorders. Methods:One hundred and sixty-seven patients with eating disorders[Anorexia Nervosa (AN), N=49; Bulimia Nervosa(BN), N=118] were recruited for this study. Perceived parent behaviors were assessed with Parental Behavior Inventory(PBI) self-rating scale. The study subjects also completed the Eating Disorder Inventory -2 (EDI-2) to assess the severity of eating disorder symptoms. Results:In anorexia nervosa, early onset group(<16 years) reported low paternal affection and high paternal rational expression, low maternal interference than group with age at onset over 16 years. The severity of eating disorder symptoms was negatively associated with mother affection and rational expression in two subtypes of eating disorder(AN and BN). On stepwise regression analysis, paternal affection and maternal over-protection were associated with age of onset only in AN group and maternal affection was associated with the severity of symptoms in both groups of eating disorder. Conclusions:Considering the role of family function and perceived parental styles could help improve the management of eating disorders. These results emphasize the importance of fathers' role in the eating disorder on the age of onset, a relatively unexplored area of eating disorder research. Also, we investigated the importance of mothers' affection on the severity of symptoms.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.5
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• pp.185-196
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• 2023

This paper investigates the effects of entrepreneurs' cognitive biases on business opportunity evaluation, given their strong entrepreneurial spirit, which is characterized by innovation, proactivity, and risk-taking. When making decisions related to business activities, entrepreneurs typically make rational judgments based on their knowledge, experience, and the advice of external experts. However, in situations of extreme stress or when quick decisions are required, they often rely on heuristics based on their cognitive biases. In particular, we often see cases where entrepreneurs fail because they make decisions based on heuristics in the process of evaluating and selecting new business opportunities that are planned to guarantee the growth and sustainability of their companies. This study was conducted in response to the need for research to clarify the effects of entrepreneurs' cognitive biases on new business opportunity evaluation, given that the cognitive biases of entrepreneurs, which are formed by repeated successful experiences, can sometimes lead to business failure. Although there have been many studies on the effects of cognitive biases on entrepreneurship and opportunity evaluation among university students and general people who aspire to start a business, there have been few studies that have clarified the relationship between cognitive biases and social networks among entrepreneurs. In contrast to previous studies, this study conducted empirical surveys of entrepreneurs only, and also conducted research on the relationship with social networks. For the study, a survey was conducted using a parallel survey method using online mobile surveys and self-report questionnaires from 150 entrepreneurs of small and medium-sized enterprises. The results of the study showed that 'overconfidence' and 'illusion of control', among the independent variables of entrepreneurs' cognitive biases, had a statistically significant positive(+) effect on business opportunity evaluation. In addition, it was confirmed that the moderating variable, social network, moderates the effect of overconfidence on business opportunity evaluation. This study showed that entrepreneurs' cognitive biases play a role in the process of evaluating and selecting new business opportunities, and that social networks play a role in moderating the structural relationship between entrepreneurs' cognitive biases and business opportunity evaluation. This study is expected to be of great help not only to entrepreneurs, but also to entrepreneur education and policy making, by showing how entrepreneurs can use cognitive biases in a positive way and the influence of social networks.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.161-168
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• 2015

Given social problems of social network service (SNS) addiction, it is critical to understand user's formation mechanism of SNS addiction. Since a number of studies have demonstrated the negative outcomes of excessive SNS use, the researchers examined important antecedents of SNS addiction as SNS habit that is considered as a key driver of SNS addiction. Moreover, the effects of self-expression, network management, and information search on SNS addition formation were investigated. The proposed theoretical model was empirically tested by using longitudinal survey data collected from 206 Facebook users. The analysis results indicate that SNS habit plays an important role in forming SNS addiction. Further, self-expression, network management, and information search influence SNS addiction through SNS habit. The analysis results offer some in-depth perspectives to SNS providers and government that establish policies or digital convergence strategies to induce healthy SNS use.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.499-502
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• 2004

DPPH radical-generating system was used to evaluate the antioxidant properties of the Rosaceae. The inhibitory effects of ethanolic extracts from Rosaceae plants were investigated on melanin biosynthesis which is closely related to hyperpigmentation. Of the Rosaceae extracts, Prunus sargentii, Rubus coreanus, Chaenomeles sinensis, Photinia glabra and Pyrus pyrifolia showed a potent inhibition of tyrosinase, the enzyme which converts 3-(3,4-dihydroxyphenyl) alanine (dopa) to dopachrome in the melanin biosynthetic process. Furthermore, MMT assay was used to check the cytotoxicity of extracts on the human foreskin fibroblast cell line, Hs68. Among the Rosaceae, bark of Prunus sargentii, bark wood of Photinia glabra and all parts or Chaenomeles sinensis showed more than $50\%$ inhibition of mushroom tyrosinase activity at 100 ug/mL and more than $80\%$ of strong DPPH radical-scavenging activity at 10 ug/mL. In audition to, they had no cytotoxic activity on Hs68. These results suggest that these extracts might be except a controler in pigmentation.

• KSBB Journal
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• v.14 no.3
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• pp.297-302
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• 1999

The polymeric matrices coated with poly(DL-lactide) were prepared using chitosan derivatives such as chitosan, chitosan hydrochloride, and sulfonated chitosan for application of drug delivery systems. The drug release study using prednisolone as a model drug was performed in the hydrochloride solution at pH 1.2. The release rate of drug was decreased according to the increased content of matrices. The release rate of prednisolone according to the kinds of polymeric matrices coated were decreased in the order to chitosan, sulfonated chitosan, and chitosan hydrochloride. Drug release rate of polymeric matrices coated with poly(DL-lactide) was not only two times slower than noncoated one, but also the burst effect of initial period of drug release was decreased in comparison with noncoated one. From these results, it was expected that these formulations based on the chitosan derivative matrices coasted with poly(DL-lactide) were acceptable drug delivery devices for a sustained-release dosage form of drug.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.207-215
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• 2018

In this study, targeting KOSPI and KOSDAQ listed companies, the relationship between the abnormal investment of companies and analyst earnings forecasts was empirically analyzed. The analysis period of this study spanned from 2003 to 2015 (with that of dependent variables spanning from 2004 to 2016) based on the variables of interest, and among the companies whose earnings per share forecasts were announced by financial analysts, the final sample of 4,917 companies/year that meets the research condition was selected as the target analysis. The results of the empirical analysis are as follows. First, it turned out that the more total abnormal investment, abnormal R&D and abnormal CAPEX investment, the more accurate were analyst earnings forecasts. Second, the more total abnormal investment, abnormal R&D, abnormal CAPEX investment, the more pessimistic analyst earnings forecasts tended to be. Further analysis has shown that these results came more from over investment groups than under investment groups. The results of this study are expected to make additional contributions to the existing studies in that the abnormal investment is considered as a determinant of analyst earnings forecasts.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.95-103
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• 2014

Given social problems of technology addiction such as games and mobile messenger services (MMSs), it have become important to understand theoretical mechanisms to generate technology addiction. In this vein, this study examined key antecedents of technology addiction in the MMS environment. We posit technology habit and user satisfaction as key predictors of technology addiction. In addition, the impacts of social interaction and flow on use's technology addition formation were investigated The research framework was tested by using survey data collected from 278 Kakaotalk users who have used more than 6 months. The analysis results found that both technology habit and user satisfaction play an important role in generating technology addiction in the MMS context. The findings of this study indicate that social interaction and flow significantly affects technology habit and user satisfaction. The analysis results help government and MMS providers establish policies or strategies to induce healthy MMS use.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.296-308
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• 2021

Electroencephalography (EEG) provides the most accurate and quickest diagnosis of epilepsy. It is also an important examination for the real-time evaluation of brain function and seizures, no matter where. In the field of epilepsy, it is appropriate for a clinical pathologist with considerable knowledge of EEG and clinical experience to perform the role of a Physician Assistant (PA). The electrode attachment method is based on the international 10-20 system. The EEG reading is mainly taken by longitudinal bipolar montage. However, a reading using only one montage may result in an error. Hence, two or more montages should be used for readings according to the clinical situation. In the EEG, electric potentials are seen as contour lines. The most important principle in EEG reading is under-reading, not over-reading. The higher the repetitions of the EEG recording, the greater the sensitivity of the reading. For a good reading, the EEG recording must be of good quality. So, the relationship between the neurologist and the EEG technician is very important. In the future, it is expected that the field of activities of the EEG technician with abundant EEG reading experience and clinical practical knowledge will be further expanded.