• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.154.2-154.2
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• 2016

In this work, we introduce a solution-processed CdS interlayer for use in inverted bulk heterojunction (BHJ) solar cells, and compare this material to a series of standard organic and inorganic cathode interlayers. Different combinations of solution-processed CdS, ZnO and conjugated polyelectrolyte (CPE) layers were compared as cathode interlayers on ITO substrates to construct inverted solar cells based on $PTB7:PC_{71}BM$ and a $P3HT:PC_{61}BM$ as photoactive layers. Introduction of a CdS interlayer significantly improved the power conversion efficiency (PCE) of inverted $PTB7:PC_{71}BM$ devices from 2.0% to 4.9%, however, this efficiency was still fairly low compared to benchmark ZnO or CPE interlayers due to a low open circuit voltage ($V_{OC}$), stemming from the deep conduction band energy of CdS. The $V_{OC}$ was greatly improved by introducing an interfacial dipole (CPE) layer on top of the CdS layer, yielding outstanding diode characteristics and a PCE of 6.8%. The best performing interlayer, however, was a single CPE layer alone, which yielded a $V_{OC}$ of 0.727 V, a FF of 63.2%, and a PCE of 7.89%. Using $P3HT:PC_{61}BM$ as an active layer, similar trends were observed. Solar cells without the cathode interlayer yielded a PCE of 0.46% with a poor $V_{OC}$ of 0.197 V and FF of 34.3%. In contrast, the use of hybrid ZnO/CPE layer as the cathode interlayer considerably improved the $V_{OC}$ of 0.599 V and FF of 53.3%, resulting the PCE of 2.99%. Our results indicate that the CdS layer yields excellent diode characteristics, however, performs slightly worse than benchmark ZnO and CPE layers in solar cell devices due to parasitic absorption below 550 nm. These results suggest that the hybrid inorganic/organic interlayer materials are promising candidates as cathode interlayers for high efficiency inverted solar cells through the modification of interface contacts.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.579-586
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• 2018

Short-term prediction of travel speed has been widely studied using data-driven non-parametric techniques. There is, however, a lack of research on the prediction aimed at urban areas due to their complex dynamics stemming from traffic signals and intersections. The purpose of this study is to develop a hybrid approach combining ensemble empirical mode decomposition (EEMD) and artificial neural network (ANN) for predicting urban travel speed. The EEMD decomposes the time-series data of travel speed into intrinsic mode functions (IMFs) and residue. The decomposed IMFs represent local characteristics of time-scale components and they are predicted using an ANN, respectively. The IMFs can be predicted more accurately than their original travel speed since they mitigate the complexity of the original data such as non-linearity, non-stationarity, and oscillation. The predicted IMFs are summed up to represent the predicted travel speed. To evaluate the proposed method, the travel speed data from the dedicated short range communication (DSRC) in Daegu City are used. Performance evaluations are conducted targeting on the links that are particularly hard to predict. The results show the developed model has the mean absolute error rate of 10.41% in the normal condition and 25.35% in the break down for the 15-min-ahead prediction, respectively, and it outperforms the simple ANN model. The developed model contributes to the provision of the reliable traffic information in urban transportation management systems.

• Korean journal of communication and information
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• v.53
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• pp.5-28
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• 2011

This research examines the recent increasingly intensified non-reporting phenomenon by the press in South Korea and its legitimacy and validity. Non-reporting denotes cases in which the press does not report on significant issues in society. Although journalism scholars have raised this question, it remains unaddressed through case studies and formal criticism. This research compares the reporting and non-reporting by major media groups of cases related to the surveillance of civilians by the National Intelligence Service and the Defense Security Command under the Ministry of National Defense. This research specifies that the non-reporting phenomenon relates not to the ability to report, but to willingness to report, due to intervention by political factionalism of media groups. The non-reporting phenomenon results from the press ignoring their basic responsibility stemming from journalistic ethics and their social responsibility to fulfill their readers' right to know. Accordingly, this research revealed that the non-reporting phenomenon cannot be justified through diverse theoretical discussions and the journalistic code of ethics. Through the logical framework of public opinions and diverse empirical data to support it, this research demonstrates that the non-reporting phenomenon produces not unhelpful, but harmful effects to resolutions to ideological dissent in South Korean society.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.334-350
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• 2010

This study aims at investigating the possible effects on the tax accounting practices stemming from adopting the IFRS in financial reporting process. It also seeks for policy implications to help alleviate practical conflicts likely to arise from the inconsistencies between the existing tax law and the tax related IFRS provisions. The results of the survey analysis are summarized as follows: firstly, majority opinion is opposed to the fair value based revaluation of property assets as well as the application of immediate recognition of foreign currency translation gains/losses. It favors the existing provision on asset securitization which adopts sales transaction view. Secondly, most of the respondents oppose the proposed amendments which allows dual classification of lease contracts on the ground. Third, functional currency appears acceptable on a conceptual level, even though a deep concern is expressed regarding the practical feasibility of computing taxable income using financial statements translated on the basis of functional currency on a practical viewpoint. Fourth, many respondents support the existing convention of recognizing depreciation expenses for taxation purposes and are in favor of the separation of accounting and tax books on a long-term basis. Fifth, the majority opinion approves the maintenance of existing tax reconciliation system and the recognition of expenses related with the doubtful accounts on reporting basis. Finally, a concern is raised with regard to the added burden of practical job loads needed to comply with the proposed amendments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.75-84
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• 2017

The prolonged economic slowdown has forced many youths to opt for starting a business instead of seeking employment. Universities have shown their interest in startup training by opening startup courses and encouraging relevant student communities, while at the same time helping their students land a job. Along with this, the government has been implementing various policies through creative economy and youth startup initiatives, but the resulting quantitative growth has not been supported by a commensurate level of qualitative growth and this has created problems on the supplier side, such as by producing redundant functions and roles in multiple projects and inefficient investment. This study, which aims at proposing a direction towards more active support and thus helping the government achieve qualitative accomplishments that can match its effort in terms of quantitative growth, analyzes the current status of startup support of universities in Korea by examining the data regarding training programs and projects, and highlights the issues stemming from startup organizations in colleges. It also suggests solutions for improving in-college startup training and establishing an interlinked system among the relevant bodies in and out of college, with the hope that the results and alternatives proposed in this study will be utilized as the basis for more active student startup support activities.

• Korean Security Journal
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• no.62
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• pp.347-367
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• 2020

Rapid advancement of technology in today's society has allowed for easy access and use of data, promoting the process of informationization. Along with the merits of such development, unintended consequences of security risks involving wiretapping have been increasing as well. The security threats posed by wiretapping technology must be addressed by every organization and individual, as it could be used to leak confidential information about the nation's security, military and diplomatic strategies, industrial technologies, and personal information. Despite increasing threats stemming from the surrounding nations using advanced wiretapping technology, there is a lack of awareness at the government level, and the existing security measures for detecting and counteracting the wiretapping equipment are ineffective. In this research, the authors offered technical suggestions for improving the security strategies against the threats of wiretapping and information leakage by conducting a content analysis. The authors suggested the units of an agency be assigned a security grade based on its importance, and that adequate security equipment should be operated according to the grade. For instance, around-the-clock surveillance is recommended for grade-1 facilities, and portable wiretapping equipment detectors should be used to protect conference rooms and other key sites.

• The Journal of Korean Society for School & Community Health Education
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• v.7
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• pp.59-74
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• 2006

Objectives: The purpose of this research is to find out the relations among children‘s perceived competences, expressive disposition of interpersonal relations, and parents’ social support, which influence their self image. Methods: The samples to achieve the purpose of this research are composed of 294 students in G elementary school, OO city, Kyounggido, the number of male students in the fifth year being 71, female 77, and male students in the sixth year being 73, female 73. After having excluded the data of 9 students among them due to their insincere reply, this research analyzed the data of 285 students by using SPSS WIN Ver. 13.0. Results: First, after having observed the average difference stemming from each method, this research found that there is no sexual difference in parents‘ social support. (p<.05). In children's perceived competences, female students is higher only in active aspect than male students, but there is no meaningful difference in other aspects. In expressive disposition of interpersonal relations, the showing-off and narcissistic expressive tendency of female students is higher than that of male students, but there is no meaningful difference in other aspects. Second, this research found out the meaningful static correlation among parents' social support, children's perceived competences, and expressive disposition of interpersonal relations. Parents' emotional, appreciative, and informative support has the static correlation with all the other aspects of children's perceived competences, and material support has the static correlation with children's academic, active, and general self-esteeming sense (p<.05, p<.01). Third, this research observed, of all the aspects of parents' social support and expressive disposition of interpersonal relations, what variable is affecting children's perceived competences, and found that parents' appreciative support, showing-off and narcissistic expressive tendency, material support, and informative support, each in order, has meaningful influence (p<.05, p<.01). This fact shows that the further the children recognize these supports of their parents', the more affirmatively they recognize their competences, and the further the children of showing-off and narcissistic expressive disposion recognize their competences. Conclusions: First, sampling was conducted of the fifth and sixth male and female students of OO elementary school, and so the result of this research has the applicative limitation in the generalization for all the elementary school students. Therefore this research suggests further researches by broad sampling for the more advanced generalization. Second, this research only observed the differnce of perception deriving from gender and school year, but the parents' social support levels perceived by children reveal many differnces according to children's characters or their families' variables. Therefore this research suggests subsequent researches on various variables.

• Journal of Global Scholars of Marketing Science
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• v.17 no.1
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• pp.1-21
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• 2007

This study seeks to understand the effects of information search activities and brand image on the hotel patronage intention based on the theory of reasoned action. First, it investigates the influence of attitude formed about hotel on the patronage intention. Second, it seeks to develope an alternative to TRA by looking into the effects of hotel image variable on hotel-specific attitude and patronage intention and attempts to substantiate the role of brand image as a substitute to subjective norm to increase the TRA's explanatory power. The main finding of this study are as follow; First, out of the three components of cognitive evaluation of hotel (human service, physical service and information service), human and physicial services were found to have significant influence on patronage intention. Brand image was found to exert notable influence on attitude toward hotel as well as patronage intention. Remarkably, the finding that brand image positively enhanced the TRA model sheds new strategic insight as to the usefulness of brand image as an alternative to overcome the TRA's limitation stemming from subjective norm. Third, it was learned that study subjects gave more weight to external information sources such as TV, radio, newspaper, magazine, and internet than to internal sources such as individual knowledge, experience or self image.

• Management & Information Systems Review
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• v.36 no.4
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• pp.167-185
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• 2017

With the expansion of corporate influence on civil society, companies are facing various demands and expectations on higher social responsibilities. This study discusses the influence of corporate social responsibility(CSR) on job attitude of employees when they recognize their company's CSR efforts. In this regard, it focuses on mediator effect of organizational identity by examining job satisfaction, organizational commitment, and turnover intention. Based on empirical investigation, positive influence was confirmed, stemming from recognized CSR. It influenced organizational identity, and it changed job attitudes including job satisfaction, organizational commitment, and decline of turnover intention. This result shows that if employees recognize company's sincere CSR activities and organizational values and culture are desirable, they tend to more strongly identify themselves with their organization. In sum, this paper found that organizational identity can be applied as a mediator which enhances the influence of CSR on job attitude. Lastly, it analyzed applicable implications to business management and suggestions for future research.

• Journal of the Korean Geotechnical Society
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• v.31 no.5
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• pp.35-46
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• 2015

In this study, the behavior of self-supported earth retaining wall with stabilizing piles was investigated by using a numerical study and field tests in urban excavations. This earth retaining wall can provide stable support against lateral earth pressures through its use of stabilizing piles that provide passive resistance to lateral earth pressures arising due to ground excavations. Field tests at two sites were performed to verify the performance of instrumented retaining wall with stabilizing piles. Furthermore, detailed 3D numerical analyses were conducted to provide insight into the in situ wall behavior. The 3D numerical methodology in the present study represents the behavior of the self-supported earth retaining wall with stabilizing piles. A number of 3D numerical analyses were carried out on the self-supported earth retaining wall with stabilizing piles to assess the results stemming from wide variations of influencing parameters such as the soil condition, the pile spacing, the distance between the front pile and the rear pile, and the pile embedded depth. Based on the results of the parametric study, the maximum horizontal displacement and the maximum bending moment significantly decreased when the retaining wall with stabilizing piles is used. Moreover, the horizontal displacement reduction effect of influencing parameters such as the pile spacing and the distance between the front pile and the rear pile is more sensitive in sandy soil, with a higher friction angle compared to clayey soil. In engineering practice, reducing the pile spacing and increasing the distance between the front pile and the rear pile can effectively improve the stability of the self-supported earth retaining wall with stabilizing piles.