• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_3
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• pp.1259-1267
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• 2023

In recent years, as the demand for distributed power has increased, the need for microgrids connected to grid power and renewable power generation sources has emerged. In the case of DC microgrids, reactive power does not occur, and power conversion losses are reduced compared to AC when connecting to the load and power grid[2]. With the revitalization of the DC distribution network industry, various studies and demonstrations of DC microgrids have been carried out. In the case of the recent unit distribution, its stability and effectiveness have been verified through empirical and research analysis. However, there is a lack of empirical tests to prevent chain accidents for the protection of the power grid circuits and the misoperation of the distributed power system caused by individual accidents when connecting various distributed power sources and power grids. In this paper, the operation plan of a stable multi-circuit DC distribution connection for the demonstration site was verified through the protection cooperation and operation algorithm for the stable linkage management of the DC distribution network composed of such a multi-circuit.

• Journal of Communications and Networks
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• v.18 no.4
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• pp.540-550
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• 2016

Since energy efficiency has become a significant concern for network infrastructure, next-generation network devices are expected to have embedded advanced power management capabilities. However, how to effectively exploit the green capabilities is still a big challenge, especially given the high heterogeneity of devices and their internal architectures. In this paper, we introduce a hierarchical power management architecture (HPMA) which represents physical components whose power can be monitored and controlled at various levels of a device as entities. We use energy aware state (EAS) as the power management setting mode of each device entity. The power policy controller is capable of getting information on how many EASes of the entity are manageable inside a device, and setting a certain EAS configuration for the entity. We propose the optimal local control policy which aims to minimize the router power consumption while meeting the performance constraints. A first-order Markov chain is used to model the statistical features of the network traffic load. The dynamic EAS configuration problem is formulated as a Markov decision process and solved using a dynamic programming algorithm. In addition, we demonstrate a reference implementation of the HPMA and EAS concept in a NetFPGA frequency scaled router which has the ability of toggling among five operating frequency options and/or turning off unused Ethernet ports.

• The Journal of shipping and logistics
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• v.34 no.4
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• pp.657-675
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• 2018

This study examines various policy programs for the creation of green harbors in major ports in the Northwest of the United States and suggests ways to apply them to major ports in Korea. Based on the fuzzy analysis process, the importance of major policy programs for the development of green ports in Korea was compared and analyzed. As a result of importance analysis, the Green Ship Incentive Program and the Carbon Footprint Program were identified as the most important policies. The first policy programs that should be introduced to Incheon Port are the AMP installation operation program and a vessel slowing program around the seaport. In case of Busan Port, the AMP installation operation program, the vessel slowing program around the seaport, carbon footprint, and installation of DPF were found to be excellent policies. These results may provide practical implications for policy makers of port authorities which has conducted environmental projects.

• Journal of Distribution Science
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• v.17 no.7
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• pp.99-109
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• 2019

Purpose - The purpose of this development the business model of the healthcare sector in order to promote patents satisfaction towards medical sector services improvement for the medical business model innovation to possess a competitive advantage in the medical and pharmaceutical industry. Research design, data, and methodology - Safety standard protocol from existing multidisciplinary literature is a process of theorization, which uses grounded theory methodology rather than a description of the data and the targeted phenomenon by using Jabareen (2009). The first task is to map the spectrum of food safety literature regarding the phenomenon in safety management. This process includes developing the implementation factors and other sources such as existing business models and practices into the protocol design. Results - The study suggests the conceptual framework to improve the safety management for patients' environmental sustainability performance. Conclusion - The business model may support the beneficial aspect to healthcare government's policymakers, hospital employees, and medical specialist who can apply the practical perspective of its value regarding an educational protocol. Originality/value - This study contributes to and extends our understanding of environmental sustainability performance, identifying the rationale for safety standards performance in the healthcare industry with suggested hybrid safety standards market consumer interconnector.

• Industrial Engineering and Management Systems
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• v.14 no.1
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• pp.44-57
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• 2015

In recent years, for the purpose of solving the problem regarding environment protection and resource saving, certain measures and policies have been promoted to establish a reverse supply chains (RSCs) with material flows from collection of used products to reuse the recycled parts in production of products. It is necessary to analyze behaviors of RSC members to determine the optimal operation. This paper discusses a RSC with a retailer and a manufacturer and verifies the behavior strategies of RSC members which may change over time in response to changes parameters related to the recycling promotion activity in RSC. A retailer takes two behaviors: cooperation/non-cooperation in recycling promotion activity. A manufacturer takes two behaviors: monitoring/non-monitoring of behaviors of the retailer. Evolutionary game theory combining the evolutionary theory of Darwin with game theory is adopted to clarify analytically evolutionary outcomes driven by a change in each behavior of RSC members over time. The evolutionary stable strategies (ESSs) for RSC members' behaviors are derived by using the replicator dynamics. The analysis numerically demonstrates how parameters of the recycling promotion activity: (i) sale promotion cost, (ii) monitoring cost, (iii) compensation and (iv) penalty cost affect the judgment of ESSs of behaviors of RSC members.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.445-449
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• 2014

The incidence of Cherry necrotic rusty mottle virus (CNRMV) and Cherry green ring mottle virus (CGRMV) have recently been occurred in Korea, posing a problem for sweet cherry cultivation. Since infected trees have symptomless leaves or ring-like spots on the pericarp, it is difficult to identify a viral infection. In this study, the incidence of CNRMV and CGRMV in sweet cherry in Gyeongbuk province was surveyed using a newly developed duplex reverse transcriptase polymerase chain reaction (RT-PCR) method that can detect both viruses in a single reaction. CNRMV and CGRMV co-infection rates were 29.6%, 53.6%, and 17.6%, respectively, in samples collected from three different sites (Daegu, Gyeongju and Gyeongsan) in Gyeongbuk province during 2012 and 2013. This duplex RT-PCR method offers a simple, rapid, and effective way of identifying CNRMV and CGRMV simultaneously in sweet cherry trees, which can aid in the management of viral infections that could undermine yield.

• Knowledge Management Research
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• v.15 no.3
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• pp.189-208
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• 2014

In spite of its popularity among practitioner and academic audiences, few existing studies go into any detail in examining the mechanisms of creating shared value (CSV), especially as applicable to the context of everyday operations. Nor do they provide recommendations to practitioners with regard to facilitating CSV concept. In response to this problem, I introduce benefit-sharing practice which I argue provides a solid route to the concept of CSV. Based on observations from the case study, 10 networks' benefit-sharing practices are analyzed and its featured characteristics are extracted accordingly. Findings demonstrate that such benefit-sharing models as 'Green-Development', 'Protection of the Environment', and 'Accreditation for Food Safety Management' can solve critical societal challenges while simultaneously driving greater profitability for both buyers and suppliers. The findings also suggest that benefit-sharing is a good vehicle of the realization of the CSV concept. I conclude by assessing how the findings add to the existing debate around collaborative supply-relationship and shared value. I suggest that benefit-sharing can contribute positively to the feasibility of CSV concept and, thereby, counter the assertion that CSV is the only immature-concept that lacks clear criteria of demarcation and cases for businesses to follow.

• The Journal of Information Systems
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• v.24 no.1
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• pp.169-191
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• 2015

Green supply chain management(GSCM) has emerged as an organizational system which helps organizations and their parter to achieve corporate profit by reducing environmental risk and cost. The main objective of this study is to investigate the relationship among organizational factors(manager support and organizational learning), GSCM practices(investment recovery and eco-design) and GSCM performance based on the BSC. Using a sample of 125 Korean companies, path analysis is used to test the research model. The results shows that the manager support has a positive effect on the investment recovery and eco-design. The results also suggest that the organizational learning directly affect the investment recovery, but do not affect the eco-design. The investment recovery and eco-design have effect on the GSCM performance. In addition, the competitive pressure has moderating effects on most of the relationships between the organizational factors and GSCM practices. This findings provides useful insights for managers seeking to adopt GSCM practices, and also provide useful guidelines for researchers to study GSCM performance.

• Journal of the Korean Society of Food Culture
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• v.21 no.1
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• pp.8-16
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• 2006

This study was performed by questionnaire to investigate the preference and intake frequency of Korean traditional commercial beverages. The subjects were consisted of 320 participants in Daegu and Kyungpook area. 'Chain market' scored 49.4% as purchasing place of traditional beverages. 'Tea bag' scored 31.6% as the favorite package of traditional beverages. On the reasons of drinking traditional beverage 'good for health' scored the highest with 31.3% respondents, followed by 'good smell' with 14.4%. Coffee and traditional tea were the choice of beverage after having a rich meal and on occasion of entertaining guests. The favorite foods in ordinary days were 'tea', 'alcohol', 'ice cream', 'nuts' and 'cookie'. More than thirty percent of the respondents, both male and female, raised the need of improvement in taste of traditional beverage. In the intake frequency, Korea traditional beverages obtained 1.80 points as a whole. 'Green tea' scored highest(3.40points) while 'mulberry-leaf tea' received the lowest score of 1.31 points. The preferred Korean traditional drinks were 'greed tea', 'shick hae', 'citron tea', 'misitgaru', 'maesil tea', 'rice tea' in the order. On the other hand, the preference for 'mulberry-leaf tea', 'boxthom tea', 'ginger tea', 'chrysanthemum tea' and 'omija tea' was very low. The people who are on twenties preferred 'shick hae', 'honey tea', 'citron tea', 'black tea' and 'misitgaru' more than the other generation.

• Journal of Korea Water Resources Association
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• v.37 no.4
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• pp.305-314
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• 2004

Climate change mainly due to the increase of green house gases cause different patterns of water cycle within the basin. However, it is common that current planning and management practices do not consider the effect of the climate change. So, this study evaluated the effect of climate change on the water circulation within the watershed. This study used several GCM simulations for the double $CO_2$condition for the generation of temperature and rainfall series using the Markov chain. Daily runoff series for 100 years were generated using a rainfall-runoff model. As results. annual temperature increase by ＋3.2 ∼＋4.6$^{\circ}C$, annual precipitation change －7 ∼ ＋8 %, annual runoff change －14 ∼ ＋7 %, and potential evapotranspiration amount change ＋3 ∼＋4 % for the change of 1 $^{\circ}C$ are found to be expected depending on GCM simulations. Even though the simulation results are very dependent on the GCM predictions considered, overall variability of runoff is expected to become higher than the current state.