• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.115-124
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• 2022

In this paper, we present an NFT auction service for the next generation, named NextAuction, which can reliably trade ownership of individual content using DID technology. Recently, as the types and sizes of tradable digital assets have expanded, the number of NFT transactions has also increased, and a significant number of marketplaces are being operated. But, the current user authentication methods of NFT marketplaces are done only through the associated blockchain wallets. It is desirable that ownership transfer through NFT transactions be transparently managed based on a more reliable identity authentication service. NextAuction increases the reliability of auction service participants by transparently and consistently providing identity authentication for users of auction services based on the DID technique using the Klaytn blockchain. In addition, in preparation for server failure that may occur during the auction of individual content, it provides users with a robust auction service using the BR2K technique that continuously provides consistent service through the replication of a target service. The NextAuction service is developed by extending BCON, a blockchain-based content management service.

• Economic Analysis
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• v.27 no.1
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• pp.67-90
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• 2021

This study found an interesting fact that the nonlinear relationship structure between volatility and trading volume changed before and after the COVID-19 pandemic according to empirical analysis using Bitcoin (BTC) market data that sensitively reflects investors' trading behavior. That is, their relationship appeared positive (+) in a stable market state before COVID-19 pandemic, as in theory based on the information flow paradigm. In a state under severe market stress due to COVID-19 pandemic, however, their dependence structure changed and even negative (-). This can be seen as a consequence of increased market stress caused by COVID-19 pandemics from a behavioral economics perspective, resulting in structural changes in the asset market and a significant impact on the nonlinear dependence of volatility and trading volume (in particular, their dependence at extreme quantiles). Hence, it should be recognized that in addition to information flows, psychological phenomena such as behavioral biases or herd behavior, which are closely related to market stress, can be a key in changing their dependence structure. For empirical analysis, this study performs a test of Ross (2015) for detecting a structural change, and proposes a Copula Regression Quantiles (CRQ) approach that can identify their nonlinear relationship structure and the asymmetric dependence in their distribution tails without the assumption of i.i.d. random variable. In addition, it was confirmed that when the relationship between their extreme values was analyzed by linear models, incorrect results could be derived due to model specification errors.

• Economic Analysis
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• v.26 no.2
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• pp.72-113
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• 2020

This study investigates the relationship between mineral exports to China, North Korea's most important source of foreign currency acquisition, and its imports of various items from China from the first quarter of 1995 through to the third quarter of 2019. The results from a cointegration analysis suggest that there exists a long-run equilibrium relationship between mineral exports and imports of food, fuel, and some intermediate goods, such as industrial supplies, parts, and accessories. The results from a vector autoregression using first-differenced variables indicate that the short-run relationship between mineral exports and imports is different between the period before and after the third quarter of 2010. Prior to structural changes, i.e., before the third quarter of 2010, import shocks affected mineral exports. However, after the third quarter of 2010, an increase in mineral exports led to an increase in the import of vehicles, intermediate goods, and luxury goods. This paper shows both the possibilities and the limits that mineral exports can contribute to North Korea's economic growth. The results, which show that mineral exports have a long-run relationship with intermediate goods, such as industrial supplies, parts and accessories, imply that mineral exports to China could have a positive effect on the North Korean economy. However, the fact that mineral exports do not have any significant effect on the import of machinery and equipment, which helps the accumulation of capital formation, shows that mineral exports have a limited effect on inducing long-term growth in the North Korean economy.

• Information Systems Review
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• v.18 no.4
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• pp.121-140
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• 2016

Today, consumers are interested in branded apps as new marketing channels. Consumers do not have ready access to information that will enable them to judge the quality of a particular product or service before purchase, but they will gain such information with branded apps. As they need to be actively chosen and downloaded to users' smartphone by the users themselves, branded apps have greater marketing effectiveness and influence than traditional channels. Therefore, corporations that place emphasis on interactions with customers anticipate a new marketing effect with their branded apps. With previous research on smartphone applications as a background, this research finds key factors in branded apps that influence users' satisfaction. Additionally, the study centers on the relationship in which satisfaction in the branded app significantly influences the purchase intention for the branded product/service.

• Journal of Platform Technology
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• v.12 no.1
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• pp.91-105
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• 2024

As the number of cases of applying IT systems to the existing isolated ICS (Industrial Control System) network environment continues to increase, security threats in the ICS environment have rapidly increased. Security threat scenarios help to design security strategies in cybersecurity training, including analysis, prediction, and response to cyberattacks. For successful cybersecurity training, research is needed to develop valid and reliable security threat scenarios for meaningful training. Therefore, this paper proposes a case-based security threat scenario development methodology for cybersecurity training in the ICS environment. To this end, we develop a methodology consisting of five steps based on analyzing actual cybersecurity incident cases targeting ICS. Threat techniques are standardized in the same form using objective data based on the MITER ATT&CK framework, and then a list of CVEs and CWEs corresponding to the threat technique is identified. Additionally, it analyzes and identifies vulnerable functions in programming used in CWE and ICS assets. Based on the data generated up to the previous stage, develop security threat scenarios for cybersecurity training for new ICS. As a result of verification through a comparative analysis between the proposed methodology and existing research confirmed that the proposed method was more effective than the existing method regarding scenario validity, appropriateness of evidence, and development of various scenarios.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.3
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• pp.502-516
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• 2014

This study has decomposed the Gini coefficient using Korean Labor & Income Panel Study data and empirically analyzed the impact of demographic characteristics and source-specific income of householder on the household income gap using panel analysis. The scope of areas were divided into 'nationwide,' 'metropolitan areas,' and 'non-metropolitan areas,' and the period before and after the global financial crisis was examined. The analysis findings are as follows. First, when the entire period was examined by income source using Gini decomposition with division of areas into 'nationwide,' 'metropolitan areas,' and 'non-metropolitan areas', the following results were revealed. The absolute and relative contribution level of property income to the gross income was the largest in the category of 'nationwide' and 'metropolitan areas,' while the contribution level of earned income was the largest in the category of 'non-metropolitan areas'. In addition, property income worsened the household income gap the most in the category of 'nationwide' and 'metropolitan areas.' Second, property income worsened the household income gap less after the financial crisis than before the crisis. It is probably because the price of real estate skyrocketed before the global financial crisis, worsening the household income gap, whereas the price drop after the crisis temporarily alleviated the gap. Third, a correlation analysis revealed that households with older householders whose education is high school graduation or below had relatively low gross income, and households with higher source-specific income, especially earned income, had relatively high gross income. Fourth, when the household income determinants were compared through panel analysis with division of areas into 'nationwide,' 'metropolitan areas,' and 'non-metropolitan areas,' the following results were obtained. While the impact of earned income, financial income, and other incomes was greater in non-metropolitan areas than in metropolitan areas, the impact of property income was greater in metropolitan areas than in non-metropolitan areas. To reduce the income gap, the government should impose higher taxes on the high-income class and provide tax benefits to the low-income class, with efforts to create a wide variety of jobs. In addition, since income inequality gets worse as the proportion of incomes generated through asset holdings becomes higher, the government should focus on stabilizing property prices while paying attention to the regional differentiation when carrying out related policies.

• Journal of Distribution Science
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• v.9 no.2
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• pp.31-36
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• 2011

I conducted empirical analyses of what happens when an offline channel expands to an online channel and whether the pre-existing offline channel's competitive assets (e.g. brand reputation and level of service satisfaction) can be linked to online channel preference. I found that an offline channel's brand reputation and level of service satisfaction can have a direct influence on offline channel preference and a second-hand influence on online channel preference. Thus, if the competitiveness of the online channel is strong enough and its customers have a higher preference for the offline channel, they will be committed and loyal to the company. The resultant enhanced competitiveness of the offline channel will present opportunities for both present and future success. The main results are the following. First, the management of the distribution channel service quality is more important than that of the brand reputation. Customers' experiences of service and subjective evaluations are not important only as the leading factors in the long-term brand reputation management but also as influential factors in channel preference. SoThus, given that the service quality of the pre-existing channel is not the customers' main concern, a strategy of improving the level of service satisfaction aimed at present customers is more valuable than a wide brand positioning strategy aimed at general and new customers. Second, when an offline channel company establishes an internet shopping mall on an online channel, it is highly likely that the preference and subjective evaluation of the present customers will influence the online channel. This applies not only to the special case of an expansion from an offline intermediary channel to an online one, but also to an online channel acting as an expansion of the business model of a conventional manufacturing or service company: both cases are vertical integrations of marketing channels in an expansion of the distribution channel. My theory applies to a wide range of contexts. Third and finally, any business strategy can grasp the meaning of 'channel expansion. Fundamentally, it is an expansion of the sales activity channel and marketing activity. However, it is also a way of enhancing marketing and sales competitiveness through an expansion to an online or offline channel. The expansion of an offline company to an online channel could be seen not as improvement but as an innovation of the business process by which two goals are achieved with one technique. The former is expected to increase the sales of the offline company, and the latter is also expected to increase sales while also contributing to cost reduction.

• Management & Information Systems Review
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• v.35 no.1
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• pp.189-206
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• 2016

It was required to attach the documents on the details of external audit including the number of the participants in external audit, audited parts and audit times under the Article 7-2 on the audit report to the accounting audit report from 2014 in accordance with the amendment to the Act on External Audit of Stock Companies. This study aim to calculate the audit fee based on the estimated cost of service calculation of the government contribution agencies by reflecting the implementation of the revised external audit. This study calculated the audit fee for the target company (a listed company assumed to have no internal control risks and relevant audit risks for unqualified opinion in the previous year, 100 billion won of total amount of asset, manufacturing company in the previous year and preliminary client request) by putting together four items of expenditure including employment costs, expenditure, general management expenses and profit in accordance with the calculation system of cost of service under the State Contract Act. Then, it used the data collected from the documents on the details of the revised external audit after requesting estimation on the target company with the estimated cost to Big-4 accounting firms to identify the participants and times of the accounting audit. The employment costs applied 150% of participation rate of the base price of employment costs for the academic research service cost in 2014, the expenditure used the average value of accounting firms of corporate business management analysis of the Bank of Korea (2013), the general management expenses applied 5% of the general management rate of service business under Article 7-1 of the Enforcement Rule of the Act on Contracts to which the State is a Party and the profit applied 10% of profit rate of service business under Article 7-2 of the Enforcement Rule of the Act on Contracts to which the State is a Party. Based on the calculation of the estimated costs by applying the above, the audit fee was estimated at 50,617,769won. Although the result is not the optimal audit fee, it may be used as a basic scale to compare the audit fees of companies without criteria. Also, such amendment to the Act on External Audit of Stock Companies may improve independence of auditors and transparency of the accounting system rather than previous announcing only the total audit times.

• Management & Information Systems Review
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• v.35 no.1
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• pp.51-68
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• 2016

In this paper, we aim to analyze the effect of accounting policy change subsequent to the adoption of K-IFRS in Korea, whereby the firms are required to recognize impairment losses on goodwill on a periodic basis rather than to amortize over a specific period. As a principle-based accounting standard, the K-IFRS expands the scope of fair value measurement with a view to enhance the relevance and timeliness of accounting information. In the same vein, intangibles with indefinite useful life, of which goodwill is an example, are subject to regulatory impairment tests at least once a year. Related literature on the impact of mandatory change in goodwill policy document that impairment recognition is more likely to be practiced opportunistically, mainly because managers have a greater discretion to conduct the tests under K-IFRS. However, existing literature examined the frequency and/or magnitude of the goodwill impairment before versus after the K-IFRS adoption, failing to notice the impairment symptoms at individual firm level. Borrowing the definition of impairment symptoms suggested by Ramanna and Watts(2012), this study performs a series of tests to determine whether the goodwill impairment recognition achieves the goal of communicating timelier information under the K-IFRS regime. Using 947 firm-year observations from domestic companies listed in KRX and KOSDAQ markets from 2008 to 2011, we document overall delays in recognizing impairment losses on goodwill after the adoption of K-IFRS relative to prior period, based on logistic and OLS regression analyses. The results are qualitatively similar in robustness tests, which use alternative proxy for goodwill impairment symptom. Afore-mentioned results indicate that managers are likely to take advantage of the increased discretion to recognize the impairment losses on goodwill rather than to provide timelier information on impairment, inconsistent with the goal of regulatory authority, which is in line with the improvement of timeliness and relevance of accounting information in conjunction with the full implementation of K-IFRS. This study contributes to the extant literature on goodwill impairment from a methodological viewpoint. We believe that the method employed in this paper potentially diminishes the bias inherent in researches relying on ex post impairment recognition, by conducting tests based on ex ante impairment symptoms, which allows direct examination of the timeliness changes between before and after K-IFRS adoption.

• Management & Information Systems Review
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• v.37 no.4
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• pp.1-20
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• 2018

This study aimed to examine earnings quality of firms selected as Global Champs project which has been promoted by the government since 2013 to support small and medium sized enterprises, for the screening year(t-1) and selected year(t). Earing quality is measured as the value of discretionary accruals estimated by Dechow et al.(1995) adjusted Jones model and Kothari et al.(2005) model, respectively. I analyze the differences of earning quality between the Global Champ firms and the paired firms selected through criteria of the similar total assets and the same industry in the screening year and the selected year. This study is motivated by the needs of measurement of the performance of the Project from the accounting transparent point of view. As the results of this study, major findings are summarized as follows. Firstly the earnings quality of the selected firms was lower than that of the paired firms. This can be explained as a result of motivation of earnings management by companies eager to meet the requirements to be selected for the Project. Secondly, in the selected year, the earnings quality was proved to improve, comparing to the screening year. This can be explained by the efforts of companies to reinforce management innovation and transparent management, which in turn led to positive effects on the earnings quality. These findings were found to be consistent in the additional analyses, where the earning quality of the reconstructed sample with only selected companies was compared for the screening year and the selected year, based on the year before the screening year(t-2).