• Journal of Korea Water Resources Association
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• v.40 no.2 s.175
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• pp.147-158
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• 2007

This study attempted to determine a suitable hydrologic model for assessing the impact of climate change on water resources, and to assess the accuracy of streamflow scenarios simulated by the selected hydrologic model using the meteorological scenarios of the Seoul National University Regional Climate Model(SNURCM). Comparison of four water balance models and two daily conceptual rainfall-runoff models for the simulation capability of the Daecheong Dam inflow indicated that the abcd model performs the best among the tested water balance models and performs as well as SSARR that is popular as a daily rainfall-runoff model in Korea. Parameters of the abcd model were then estimated for 12 ungauged subbasins of the Geum River by the regionalization method. The model parameters were first calibrated at nine multi-purpose dams and were then regionalized using catchment characteristics for another four multi-purpose dams, which were assumed to be ungauged sites. The model efficiency(ME) coefficients of the simulated inflows for these four dams were at least 87%. The MEs of the hindcasted meteorological rainfall scenarios of the 12 subbasins of the Geum River were more than 60%. Moreover, the ME of the Daecheong Dam inflow simulated by the abcd model using the SNURCM rainfall scenarios was more than 80%. Therefore, this research concluded that the abcd model coupled with the SNU-RCM meteorological scenarios can be used for impact assessment studies of climate change on water resources.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.1
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• pp.90-97
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• 1992

An estimation method for the amplitude and phase response of transmission line is discussed. and applied to narrow band ISDN subscriber line. The ABCD parameters of line are evaluated from four impedance values: the standard termination impedence at activated and deactivated stares, and the input impedances of line which can be estimated at each state. Estimating input impedence, the “chirp” signal is used as incident signal and noise effect can be reduced by ensemble averaging. These ABCD parameter estimations might be applicable to ether uniform or nonuniform line. Cleary the magnitude and phase response can be obtained from estimated ABCD parameters. The numerical simulation results for N ISDN subscriber line model are included, and the estimation error introduced by deviation in load impedence is also anlyzed.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.211-217
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• 2018

The purpose of this paper is to explore the possibility and strategic directions of Korean agriculture in the future by analyzing domestic and foreign successful cases leading to the 6th industrialization of agriculture by utilizing 4th Industrial Revolution technologies. To do this, we surveyed the key technologies of the 4th Industrial Revolution, and examined successful cases of the US, Korea and China. As results of these case studies, we recognized that 4th Industrial Revolution technologies could play important roles in the 6th industrialization of agriculture, and suggested meaningful strategic implications using ABCD model.

• The Journal of Economics, Marketing and Management
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• v.12 no.2
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• pp.73-81
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• 2024

Purpose: South Korea is a close ally of the US and an important partner of China. Caught between the two most powerful countries, South Korea's strategic directions are critical. This article emphasizes that the deeper core of the US-China trade war is to improve the business environment to attract foreign direct investment (FDI) to boost the economy, rather than engaging in the trade war. Research design, data, and methodology: Considering the complexity of this issue, this article applies a systematic analytical tool, the ABCD (Agility, Benchmarking, Convergence, and Dedication) model, to provide strategic guidance for inducing investments into South Korea in the context of the ongoing US-China trade war. Results: Specifically, South Korea needs to provide a more attractive business environment along the four points: expedite commercial activities through deregulation (Agility); adopt global standards of the flexible labor markets and technological developments (Benchmarking); integrate various industries and connect them to global value chains (Convergence); and create more economy-friendly policies rather than politics-oriented ones such as protectionism (Dedication). Conclusion: This study stands out not just by utilizing the ABCD model but, also by providing more systematic analysis and practical implications, particularly within the context of the escalating US-China competition. Unlike many existing studies that analyze the broader impacts of this geopolitical rivalry, this research delves into specific strategic guidelines for South Korea to attract FDI. The findings also provide implications for multinational corporations (MNCs) in choosing the locations for their overseas operations, particularly in South Korea.

• Journal of Korea Water Resources Association
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• v.50 no.7
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• pp.489-502
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• 2017

The objective of this study is to propose and evaluate the BAYES-ESP, which is a dam inflow prediction method based on Ensemble Streamflow Prediction method (ESP) and Bayesian theory. ABCD rainfall-runoff model was used to predict monthly dam inflow. Monthly meteorological data collected from KMA, MOLIT and K-water and dam inflow data collected from K-water were used for the model calibration and verification. To estimate the performance of ABCD model, ESP and BAYES-ESP method, time series analysis and skill score (SS) during 1986~2015 were used. In time series analysis monthly ESP dam inflow prediction values were nearly similar for every years, particularly less accurate in wet and dry years. The proposed BAYES-ESP improved the performance of ESP, especially in wet year. The SS was used for quantitative analysis of monthly mean of observed dam inflows, predicted values from ESP and BAYES-ESP. The results indicated that the SS values of ESP were relatively high in January, February and March but negative values in the other months. It also showed that the BAYES-ESP improved ESP when the values from ESP and observation have a relatively apparent linear relationship. We concluded that the existing ESP method has a limitation to predict dam inflow in Korea due to the seasonality of precipitation pattern and the proposed BAYES-ESP is meaningful for improving dam inflow prediction accuracy of ESP.

• Journal of Industrial Convergence
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• v.19 no.6
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• pp.1-10
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• 2021

This study sought ways to strengthen the competitiveness of local governments using public diplomacy, especially in Chungcheongbuk-do, at a time when it is urgent to revitalize the local economy by attracting investment from domestic and foreign companies due to changes in the global supply chain. The main issues that have recently emerged in the global business environment include strengthening the localization of the global value chain, diversifying reshoring and supply chains, and creating an efficient global value chain through digital transformation. Therefore, this study emphasized the necessity of a strategy for public diplomacy based on these changes, and derived the response conditions and detailed strategies of Chungcheongbuk-do through SWOT analysis. In addition, based on the ABCD model, we set up a Chungbuk-type public diplomacy strategy and suggested strategic implications for upgrading Chungbuk's competitiveness.

• Korea Trade Review
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• v.44 no.4
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• pp.87-100
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• 2019

A country's participation in international technical standards development directly relates to its trade competitiveness. Many countries adopt international standards or influence their development process through the ISO/IEC. This study applies the ABCD Model to assess such activities through a constructed ITS index, not only in terms of 'level' of contribution but also in terms of 'process' participation that can give important implications related to the future potential influence of countries in standards development. Having examined seven countries, Korea showed the lowest score implying the need to enhance its performance in both 'international standards adoption' and 'internationalization of domestic standards'. Korea needs to more actively participate in currently on-going standards development processes, establish more offices that improve accuracy in the development, and consider participating in additional committees where domestic interests may potentially be at stake. Although KATS has improved greatly in regards to its relevant activities and database construction, a more active and specific plan must be made to allow its efforts to successfully influence Korea in international standards development. Confronted with strong challenges from directly competing countries in trade like China and Japan that showed better ITS scores, there is a need for Korea to step up its research and participation in this field.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.4 s.334
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• pp.45-52
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• 2005

This paper presents the characterization of through hole vias on printed circuit board (PCB) through the time domain and frequency domain measurements. The time domain measurement was performed on a single via using the TDR, and the model parameters were extracted by the fitting simulation using HSPICE. The frequency domain measurement was also performed by using 2 port VNA, and the model parameters were extracted by fitting simulation with ADS. Using the ABCD matrices, the do-embedding equations were derived probing in the same plane in the VNA measurement. Based on the single via characterization, the differential via characterization was also performed by using TDR measurements. The time domain measurements were performed by using the odd mode and even mode sources in TDR module, and the Parameter values were extracted by fitting with HSPICE. Comparing measurements with simulations, the maximum calculated differences were $14\%$ for single vias and $17\%$ for differential vias.

• Journal of Korea Water Resources Association
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• v.51 no.6
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• pp.523-533
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• 2018

The objective of this study is to analyze uncertainties of ensemble-based streamflow prediction method for model parameters and input data. ESP (Ensemble Streamflow Prediction) and BAYES-ESP (Bayesian-ESP) based on ABCD rainfall-runoff model were selected as streamflow prediction method. GLUE (Generalized Likelihood Uncertainty Estimation) was applied for the analysis of parameter uncertainty. The analysis of input uncertainty was performed according to the duration of meteorological scenarios for ESP. The result showed that parameter uncertainty was much more significant than input uncertainty for the ensemble-based streamflow prediction. It also indicated that the duration of observed meteorological data was appropriate to using more than 20 years. And the BAYES-ESP was effective to reduce uncertainty of ESP method. It is concluded that this analysis is meaningful for elaborating characteristics of ESP method and error factors of ensemble-based streamflow prediction method.

• Journal of Korea Trade
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• v.25 no.3
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• pp.153-168
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• 2021

Purpose - In this study, we aim to explore new distribution strategies for sustainable growth in the era of the 4th industrial revolution, focusing on SMEs (small and medium-sized enterprises) in Korea, and suggest ways to upgrade the government's official distribution channel to the next level. Design/methodology - First of all, this paper explored the prior research, the current status of sales support for SMEs, and the changes in the distribution industry due to COVID-19 pandemic. Based on Moon (2016)'s ABCD strategic model - Agility, Benchmarking, Convergence, and Dedication, the study then derived directions in which official distribution channels should move and the new distribution strategy for Korean SMEs to secure competitive advantage. Findings - First, in terms of 'Agility', in order to upgrade official distribution channels, which are currently at some competitive disadvantages compared to private distribution companies, we must quickly introduce technologies for the 4th industrial revolution, such as AI, Big Data, etc., and establish precise strategies to strengthen the capabilities of SMEs. Second, in terms of 'Benchmarking', the use of "Chamelezones" has been increasing to enhance the competitiveness of offline stores in line with recent ontact trends. Therefore, official distribution channels should also benchmark such cases, strengthening their competitiveness by utilizing offline spaces more efficiently and effectively. Third, in terms of 'Convergence', in line with the rapidly changing trend of the times, official distribution channels should also promote active partnerships with media commerce, e-commerce and ICT platforms, as well as cooperation with private retailers, and focus on creating synergy effects through them. Finally, from the perspective of 'Dedication', digitalization should be promoted step by step, finding the sector that can accelerate digital among the value chains of official distribution channels, and continuing to discuss how to digitize it realistically. Originality/value - Based on this analysis, we have presented strategies and implications for innovating official distribution channels for SMEs, which will contribute to enhancing the competitive advantage of official distribution channels in the post COVID-19 pandemic era.