• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.1-8
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• 2019

The integrity of the Reactor Pressure Vessel (RPV) is affected by the neutrons bombarding the vessel wall leading to embrittlement. This irradiation-induced embrittlement leads to reduction in the fracture toughness of RPV materials. This paper presents a comparative study of typical Optimized Power Reactor (OPR)1000 reactor pressure-temperature (P-T) limit curves using the pre-2006 American Society of Mechanical Engineers (ASME) editions used in the power plant and the current ASME edition of 2010. The current ASME Code utilizes critical reference stress intensity factor based on the lower bound of static, while the Pre-2006 ASME editions are based the critical reference stress intensity factor based on the lower bound of static, dynamic and crack arrest. Model-Based Systems Engineering approach was used to evaluate ASME Code Section XI Appendix G for generating the P-T limit curves. The results obtained from this analysis indicate decrease in conservatism in P-T limit curves constructed using the current 2017 ASME code, which can potentially increase operational flexibility and plant safety. Hence it is recommended to use ASME code edition after 2006 be used in all operating nuclear power plants (NPPs) to establish P-T limit curve.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.5
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• pp.1-11
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• 2000

A control system using a programmable logic controller (PLC) has been developed for a dual tower dryer (DTD) in a canadian deuterium natural uranium reactor (CADND) type nuclear power plant. This system will replace the existing DTD control system which was implemented with mechanical timers and relays. The new control system makes it possible for an operator to perform more precise time and dew point control for the DTD, thanks to the high efficiency and flexibility of the PLC. The operational cost for the control system is much reduced compared to the existing system.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.64
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• pp.239-264
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• 2014

Two types of responses to climate change exist. First is climate mitigation which includes efforts of reducing CO2 and GHG emissions. Second response is climate adaptation process which is establishing climate resilience in the supply chain. The two are inherently different since mitigation strategy focus on eliminating the source of climate change and is long term in nature but adaptation strategy is moderating the impact of potential or current climate change. In order to embed climate resilience in the supply chain, mitigation strategies and adaption strategies must be implemented simultaneously. Corporation's adaptation to climate change related natural disaster can be seen as a response that includes mitigation and adaptation strategies simultaneously. A comprehensive climate change resilience supply chain approach has to be developed. This paper illustrated guidelines and adaptation process framework businesses can utilize in order to build climate resilience. Screening process before the actual assessment of risk was introduced as well as the whole adaptation process of establishing information system and strengthening climate-related operational flexibility.

• Journal of the Korean Society of Combustion
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• v.22 no.1
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• pp.14-22
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• 2017

Co-firing of renewable fuel in coal fired boilers is an attractive option to mitigate $CO_2$ emissions, since it is a relatively low cost option for efficiently converting renewable fuel to electricity by adding biomass as partial substitute of coal. However, it would cause reducing plant efficiency and operational flexibility, and increasing operation and capital cost associated with handling and firing equipment of renewable fuels. The aim of this study is to investigate the effects of biomass co-firing on $CO_2$ emission and capital/operating cost. Wood pellet, PKS (palm kernel shell), EFB (empty fruit bunch) and sludge are considered as renewable fuels for co-firing with coal. Several approaches by the co-firing ratio are chosen from previous plant demonstrations and commercial co-firing operation, and they are evaluated and discussed for $CO_2$ reduction and cost estimation.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.3
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• pp.68-75
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• 2012

The traditional regulatory approach to managing pilots fatigue has been to prescribe limits on maximum daily, monthly, and yearly flight and duty hours, and require minimum breaks within and between duty periods. This approach comes from a long history of limits on working hours dating back to the industrial revolution. So, the Council of ICAO recently adopted International Commercial Air Transport regarding the development and implementation of fatigue risk management systems(FRMS). The FRMS can provide better safety outcomes than current prescriptive flight and duty regulations while allowing greater operational flexibility. This study aim to analyzing relative importance of pilots' fatigue factors in order to minimize pilots' fatigue-related safety risks. More researches regarding monitoring and managing fatigue, based upon scientific principles, are required in the future.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.269-274
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• 2004

The performance of a newly designed wastewater treatment process equipped with an anaerobic and two intermittent aeration tanks operated alternately was investigated. During the experimental period, several types of cyclic operating schedules with different aeration and non aeration time were examined for the optimization. At all modes, the removals of organic matter and SS were highly achieved. With respect to T-N removal, however, the cycle length for aeration on/off affected the efficiencies. At the optimal operating mode, the ORP bending point indicating the disappearance of nitrate was observed. Considering the influent wastewater characteristics and cyclic operating schedules, it can be suggested that T-P removal is much more BOD/T-P ratio and/or its load dependant rather than the aeration on/off time. The results obtained from pilot-scale test showed the competitive advantage of this alternating process through an omission of nitrate recycle and operational flexibility against influent load variations when comparing with other continuous flow processes.

• Journal of the Korea Society of Computer and Information
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• v.7 no.1
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• pp.137-146
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• 2002

The benefit of TPL(Third-party Logistics) is reduction of transportation time, accuracy, improved expertise knowledge and access to logistics information system, improved operational efficiency, improved customer service, ability to focus in core business and greater flexibility. On the contrary, the defect of TPL is loss of control, unreliable promise of the enterprise (provider),inability to respond to logistics system requirement, lack of understanding of the user business goals . This thesis aims to suggest the optimal strategic to improve the logistics system and to satisfy the customer needs and also aims to suggest the TPL method to strengthen the TPL companies. And strategic plan Total (enterprise-TPL-customer) Logistics Information System(TLSI) of TPL operation. focused on transportation service and mechanism to use GPS model.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.2
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• pp.131-140
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• 2019

This study used a packed column reactor and a horizontal flow mesh reactor to examine the removal of copper ions from aqueous solutions using pine bark, a natural adsorbent prepared from Korean red pine (Pinus densiflora). Both equilibrium and nonequilibrium adsorption experiments were conducted on copper ion concentrations of 10mg/L, and the removals of copper ions at equilibrium were close to 95%. Adsorption of copper ions could be well described by both the Langmuir and Freundlich adsorption isotherms. The bark was treated with nitric acid to enhance efficiency of copper removal, and sorption capacity was improved by about 48% at equilibrium; mechanisms such as ion exchange and chelation may have been involved in the sorption process. A pseudo second-order kinetic model described the kinetic behavior of the copper ion adsorption onto the bark. Regeneration with nitric acid resulted in extended use of spent bark in the packed column. The horizontal flow mesh reactor allowed approximately 80% removal efficiency, demonstrating its operational flexibility and the potential for its practical use as a bark filter reactor.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.1395-1403
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• 2021

The COVID-19 pandemic is having an adverse impact on Bangladesh's economy by affecting millions of people's life and hampering their income sources. The outbreak of COVID-19 has created more pressure on the labor market. The pandemic reduces employment opportunities as most of the companies have stopped their recruitment process to cut their operational costs, which increases the rate of graduate unemployment in Bangladesh. Hence, this study aims to investigate the impact of COVID-19 on graduate employability in Bangladesh that adversely affects the income of families and eventually the nation's economy. A literature review has been conducted from secondary sources to evaluate the impact, which shows that the rate of graduate unemployment increased from 47% to 58% in 2020 with an expected annual loss estimated at $53 million. Findings also reveal that the prime reasons for graduate employability are low demand and huge supply of graduates in the labor market, lack of professional skills of graduates, ineffective education system, etc. The study suggests that the government of Bangladesh should develop some policies to overcome this problem such as ensuring employment subsidies, implementing skills development programs, improving labor market flexibility, initiating credit programs for generating employment, and developing entrepreneurial ecosystems in Bangladesh.

• Asia-Pacific Journal of Business
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• v.13 no.3
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• pp.171-182
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• 2022

Purpose - The main purpose of this study is to test two competing hypotheses on the relationship between foreignness and corporate philanthropy drawing on the resource dependence theory. Design/methodology/approach - This study used Korean Enterprsie Survey data constructed by Korean Statistical Information Service. This study employed both OLS and Tobit models to test the hypotheses. Findings - A conventional wisdom can argue that MNC subsidiaries are more willing to give charitable donations than local firms do because they may perceive philanthropy in the host country is a good opportunity to reduce liabilities of foreignness (H1-1). On the other hand, one can argue that MNC subsidiaries are less willing to give charitable donations than local firms do because they have operational flexibility when they are coerced to engage in corporate philanthropy by host country government stakeholders (H1-2). Empirical results support the prediction that MNC subsidiaries are less likely to give charitable donations than local firms do in Korea. Research implications or Originality - Our findings can provide useful insights to researchers and managers in the sense that MNC managers can increase or decrease their charitable donations depending on the institutional contingencies in different host countries. These institutional contingencies are particularly important within a transforming context such as Korea.