• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.162-162
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• 2019

Water Distribution Network (WDN) is a critical infrastructure to be maintained ensuring proper water supply to wide-spread consumers. The WDN consists of pipes, valves, pumps and tanks, and these elements interact each other to provide adequate system performance. If elements fail by internal or external interruptions, it may result in adverse impact to water service with different degree depending on the failed element. To determine an appropriate maintenance priority, the critical elements need to be identified and mapped in the network. In order to identify and prioritize the critical elements in WDN, an element-based simulation approach is proposed, in which all the elements composing the WDN are reviewed one at a time. The element-based criticality is measured using several resilience indexes that are newly developed in this study. The proposed resilience indexes are used to quantify the impacts of element failure to water service degradation. Here, three resilience indexes are developed, such as User Demand Severity, Economic Value Loss and Water Age Degradation, each of which intends to measure different aspects of consequences, such as social, economic, and water quality, respectively. For demonstration, the proposed approach is applied to a benchmark water network to identify and prioritize the critical elements.

• Proceedings of the Korea Port Economic Association Conference
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• 2003.07a
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• pp.271-294
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• 2003

In this article, 1'd like to analyse the principal distinctions between the duty of disclosure and warranty which are based on the same legal principles, utmost good faith(uberrima fides). Although the duty of disclosure and warranty have a same legal principle to protect insurance contract, they have several difference in appliance actually. Through these comparative analysis, I want to reveal the character of warranty which is unfamiliar to us under our commercial law. Warranty has some peculiarity, these are (a)A warranty does not have to be material to the risk, (b)A warranty must be exactly complied with, (c)It is impossible to defence for a breach of warranty, the breach of warranty is irremediable, and A casual connection between breach and loss needs not be shone, (d)A breach of a warranty may be waived by insurer. Sometimes in Korea like those stringent principles of warranty make Korean's small fishing or shipping company suffer from difficult because of insistence of discharge from liability by insurer. So I expect that all of them acknowledge the character of warranty and can make them protect their insurance money by themselves.

• Journal of Regulation Studies
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• v.27 no.1
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• pp.123-151
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• 2018

There have been voluminous debates on the economic effects of the Sunday shopping restriction in Korea. This paper summarizes the issues on the restriction, critically reviews the previous researches, and proposes policy alternatives. First, the Sunday shopping restriction in Korea significantly lowers supply-side efficiency. Second, the restriction considerably reduces demand-side efficiency due to higher transaction costs. Third, there is no empirical evidence showing the restriction improves equity overall. Fourth, even if equity improvement occurs, there are a number of policy alternatives that can achieve the same equity effect with less efficiency loss.

• Steel and Composite Structures
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• v.38 no.4
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• pp.365-380
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• 2021

Although traditional steel-concrete composite beams have excellent structural characteristics, it cannot meet the requirement of quick assembly and repair in the engineering. This paper presents a study on static behavior of bolt connected steel-concrete composite beam without post-cast zone. A three-dimensional finite element model was developed with its accuracy and reliability validated by available experimental results. The analysis results show that in the normal service stage, the bolt is basically in the state of unidirectional stress with the loss of pretightening can be ignored. Parametric studies are presented to quantify the effects of the post-cast zone, size and position of splicing gap on the behavior of the beam. Based on the studies, suggested size of gap and installation order were proposed. It is also confirmed that optimized concrete slab in mid-span can reduce the requirement of construction accuracy.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.477-482
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• 2021

Hydrogen production, hydrogen production cost, and utilization rate were calculated assuming four cases of hydrogen production system in combination of photovoltaic power generation (PV), water electrolysis system (WE), battery energy storage system (BESS), and power grid. In the case of using the PV and WE in direct connection, the smaller the capacity of the WE, the higher the capacity factor rate and the lower the hydrogen production cost. When PV and WE are directly connected, hydrogen production occurs intermittently according to time zones and seasons. In addition to the connection of PV and WE, if BESS and power grid connection are added, the capacity factor of WE can be 100%, and stable hydrogen production is possible. If BESS is additionally installed, hydrogen production cost increases due to increase in Capital Expenditures, and Operating Expenditure also increases slightly due to charging and discharging loss. Even in a hydrogen production system that connects PV and WE, linking with power grid is advantageous in terms of stable hydrogen production and improvement of capacity factor.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.877-887
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• 2022

A new reactor concept is described that directly couples a supercritical CO₂ (sCO₂) power cycle with a CO₂-cooled, heavy water moderated pressure tube core. This configuration attains the simplification and economic potential of past direct-cycle sCO₂ concepts, while also providing safety and power density benefits by using the moderator as a heat sink for decay heat removal. A 200 MWe design is described that heavily leverages existing commercial nuclear technologies, including reactor and moderator systems from Canadian CANDU reactors and fuels and materials from UK Advanced Gas-cooled Reactors (AGRs). Descriptions are provided of the power cycle, nuclear island systems, reactor core, and safety systems, and the results of safety analyses are shown illustrating the ability of the design to withstand large-break loss of coolant accidents. The resulting design attains high efficiency while employing considerably fewer systems than current light water reactors and advanced reactor technologies, illustrating its economic promise. Prospects for the design are discussed, including the ability to demonstrate its technologies in a small (~20 MWe) initial system, and avenues for further improvement of the design using advanced technologies.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.625-634
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• 2007

Energy-saving is one of important issues in multi-family housing projects in South Korea. According to the study by Yu et al. (2002), the balcony conversion causes energy loss approximately one and a half times. Therefore, it is important to select the economical glass type in the balcony window. In order to identify the most economical glass type of balcony conversion in multi-family housing projects, the most typical type of the multifamily housing projects in the metropolitan area was selected as a candidate project. The selected candidate project has been simulated using ENERGY-10 program to estimate the heat load by the different five types of glasses as well as their life cycle cost analysis (LCCA) using present worth method. Finally, sensitivity analysis has been conducted to determine the most economical glass types under a different discount rate (interest rate) and service life of building.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.5 no.3
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• pp.86-93
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• 2024

Unintentional dispersal of organisms has explosively increased due to expansion of human activities. Among introduced organisms, some organisms are categorized as invasive species because of their effects on environmental risk, economic loss, and human health. In 2023, a leopard slug (Limax maximus) was reported in Suwon, Republic of Korea. This slug was designated as a potential invasive species because a wide range of plant species were identified as food sources for this slug in its original habitats. However, it is difficult to investigate the ecological risk of this newly introduced slug in Republic of Korea. Therefore, the potential ecological risk from this newly introduced slug was estimated by meta-genome analyses of its feces. Through meta-genome analyses, 22 Families, 28 Genera, and 26 Species of land plants were identified. Among these 26 identified plant species, six economically important crops - squash (Cucurbita maxima), tomato (Solanum lycopersicum), potato (Solanum tuberosum), cowpea (Vigna unguiculata), rice (Oryza sativa), and oriental melon (Cucumis melo) - were identified. Therefore, leopard slugs potentially could cause economic losses in Republic of Korea. Further study is required to build a control strategy against leopard slugs.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.131-136
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• 2013

Automobile was first introduced in 1903 in South Korea, the masses of the car was carried out rapidly compared to other countries. However, many people were killed in a traffic accidents and economic loss was occurred due to the spread of the automobile. In South Korea, 2012, traffic accident occurred 223,656 times, 5,392 fatality, 344,565 injured people. In the last five years, about 224,000 accidents per year were occurring. In other words, 610 traffic accidents occur and about 15 people pass away in one day. In addition, the proportion of traffic accidents is first place in the OECD countries and it is very high in the world. Understand occurrence tendency of traffic accident, accident frequency rate of the driver who drives more than 10 years was higher than the novice driver. In addition, as a result of examining the cause of the traffic accident, breach of safe driving obligation appears highest case (125,391 times), and followed by signal violation, break safety distance. Therefore, the majority of traffic accidents occurred by the lack of safety awareness of the driver. In this study, prevent the loss of human life and property in traffic disaster, by establish disaster prevention measures that investigated by questionnaire survey and statistical data of the state of consciousness and driving posture in response to the driving history of the driver.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.635-645
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• 2020

This research was conducted to achieve several objectives and focus research was based on financial behavior theory and prospect theory as grounded theory e.g., investigate the financial decision-making behavior between financial and real assets investment, and confirm the relationship existing between herding behavior and overconfidence factors to the level of loss and regret aversion, and financial literacy into real assets investment decisions. The study used 220 real estate auction respondents as investor samples at the State Assets and Auction Service Office Makassar, South Sulawesi, Indonesia. Data was collected through the use of a questionnaire consisting of 23 questions to measure the variables. Moreover, the research data passed through several feasibility tests like the inner and outer modeling by Partial Least Square - Structural equation model (PLS-SEM) while the hypotheses formulated were also tested to determine the magnitude of the variable relationship. Through the use of the direct and intervening test, loss and regret aversion variables have a positive and significant effect while financial literacy variables have no significant effect. There is a slight difference in the decision-making process for real assets and financial assets investors. Investment decision making behavior in the financial assets sector requires less complicated decisions compared to the decisions related to real assets investments.