• Advances in Energy Research
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• v.7 no.2
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• pp.147-166
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• 2020

Industrial cooling towers are often ageing infrastructure that is expensive to maintain and operate. A novel approach is introduced in which a heat pump circuit is incorporated to reduce the load upon the towers by extracting low-grade energy from the stream sent to the towers and repurposing in on-site processing operations. To demonstrate the concept, a model was constructed, which uses industrial data on cooling towers linked to a smelter's sulphuric acid plant, to allow direct economic and environmental impact comparison between different heat recovery and repurposing scenarios. The model's results showed that implementing a heat pump system would significantly decrease annual operating costs and achieve a payback period of 3 years. In addition, overall CO₂ emissions could be reduced by 42% (430,000 kg/year) and a 5% heat load reduction on the cooling towers achieved. The concept is significant as the outcomes introduce a new way for energy intensive industrial sectors, such as mineral processing, to reduce energy consumption and improve long-term sustainable performance.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.6
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• pp.560-568
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• 2005

The cost accounting of electricity and heat produced from an energy system is important in evaluating the economical efficiency and deciding the reasonable sale price. The OECOPC method, suggested by the author, was applied to a 650 MW combined cycle cogeneration system having 4 operating modes, and each unit cost of electricity and heat products was calculated. In case that a fuel cost is ${\\}400/kg$ and there are no direct and indirect cost, they were calculated as follows; electricity cost of ${\\}23,700/GJ$ at gas-turbine mode, electricity cost of ${\\}15,890/GJ$ at combined cycle mode, electricity cost of ${\\}14,146/GJ$ and heat cost of ${\\}6,466/GJ$ at cogeneration mode, and electricity cost of ${\\}14,387/GJ$ and heat cost of ${\\}4,421/GJ$ at combined cycle cogeneration mode. Further, these unit costs are applied to account benefit on this system. Since the suggested OECOPC method can be applied to any energy system, it is expected to contribute to cost accounting of various energy systems.

• Journal of the Korea Society of Computer and Information
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• v.18 no.8
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• pp.141-148
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• 2013

Traditional face-to-face university education has shifted its course to combine the advantages of both online and offline education in a blended-learning approach. However, there is still much that is unknown about the actual effect of blended learning, particularly it's learning outcomes in terms of cost effectiveness. This study qualitatively examines the costs and the learning outcomes of blended learning at an on-line college and off-line university. Online college level English pedagogy courses and blended with offline operations at an online university were studied across two semesters in terms of the quality of education, and both direct and indirect cost savings. Other causes for various learning outcomes and cost implications are proposed and validated.

• Journal of Korea Planning Association
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• v.53 no.6
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• pp.101-116
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• 2018

Paying an attention to the issue of energy poverty of low-income households and ensuing regressivity of energy consumption, this study empirically analyzes the effects of both household and housing characteristics on heating energy consumption in an integrated way and identifies their causal structure based on the 2016 Korea Housing Survey data provided by the Korean government. Multiple regression analysis shows that household income and deteriorated level of housing, such as age and degree of cracks have positive effects and floor area of housing has a negative effect on the heating energy consumption per unit area of housing (HECPUH). Path analyses further reveal that the direct effect of household income on HECPUH is offset by the indirect effects that are mediated by deteriorated level and floor area of housing, making the total effect statistically insignificant. As a result, there is no significant difference in HECPUH across all income strata, implying that low-income (high-income) households pay more (less) heating costs relative to their income level, since they reside in the houses with relatively low (high) energy efficiency. To deal with this regressive causal structure of energy consumption, a policy option is recommended to improve energy efficiency of low-income housing through the government assistance in its maintenance and repair.

• The Korean Journal of Emergency Medical Services
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• v.23 no.1
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• pp.35-48
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• 2019

Purpose: This study aimed to explore the rationality for and countermeasures against the use of prehospital patient restraint (PPR) techniques in efforts to limit violent behavior toward 119 emergency medical technicians (EMTs). Methods: Previous countermeasures to limit violent behavior toward 119 EMTs and medical personnel were focused on strict reactive and passive proactive responses. However, those in support of the countermeasures do not believe that violent and criminal behavior can be limited or extinguished by strengthening the punishment unconditionally. Results: When it comes to the far-reaching effects of stigmatization on people who engage in violent and criminal behavior, it is possible that unconditional punishment leads to more crime, increases the costs of imprisonment, and consequently, adds to the financial burden of the government. Conclusion: Thus, we are faced with an urgent need to prepare legal grounds for the use of PPR techniques by 119 EMTs for agitated or combative patients only, with direct medical oversight. Moreover, the legal foundation for the use of PPR techniques also needs to be established for emergency medical personnel. The use of PPR techniques not only ensures the safety of emergency medical services personnel, but also protects patients from injuring themselves and others.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.1
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• pp.29-36
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• 2019

In the past, social insurance premiums, such as national pension and national health insurance, is contained within the costs of construction projects, have been lowered due to price competition of companies participating in the bidding. The government is implementing the "Ex-post settlement system" to improve the problem. Therefore, the purpose of this study is to examine the concept of an Ex-post settlement system and background of its introduction and to identify problems in the management of the system. The problems of the Ex-post settlement system are: 1) avoiding the participation of construction workers, 2) the rigidity of the insurance premium settlement method in construction field, and 3) the cause of direct construction cost reduction. The ways to improve these problems are: 1) excluding social insurance premiums from construction project cost, 2) securing flexibility of the settlement method of insurance premiums in construction field, and 3) expanding the scope of persons eligible to participate in social insurance.

• Journal of Korea Society of Digital Industry and Information Management
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• v.17 no.2
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• pp.73-83
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• 2021

The development of technology based on digital technology has made 'hyper connectivity' between different services a reality, and an example of this is the reinforcement of non-face-to-face services. The non-face-to-face service is a service provided by service providers and customers using information and communication and technology without direct contact. Recently, it has expanded to the hotel industry, which is highly dependent on human resources, centering on the restaurant business. Therefore, this study attempted to identify the case of the "R" hotel in the Gangwon region, which is introducing and operating a kiosk, and to confirm the matters to be considered, the system operation method, and expected effects, etc. for hotels that intend to operate it in the future. It is difficult to affirm that the introduction of KIOSK directly reduced labor costs or increased service efficiency, but it seems meaningful that it has improved the convenience of users. In future research, practical research is needed on the impact of the system on management activities in relation to the introduction of KIOSK.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.4
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• pp.63-75
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• 2009

Recently personal information security breaches by unauthorised access, mistakenly disclosure or stolen become more frequent and the scale of the economic loss of such incidents is growing. Assessing economic loss of personal information security breaches is needed for decision making of information security investment This paper presents a framework to analyze economic impact of personal information security breaches and develops formula for each element to empirically calculate the economic loss. We also compared annual economic loss of Korea with that of Japan to develop some implications.

• Journal of Distribution Science
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• v.21 no.2
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• pp.21-34
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• 2023

Purpose: The goal of this study is to examine what makes young people more likely to use digital banking. This is because digital banking services and their distribution channels are technologically advanced, which can be a double-edged sword between ease of use and resistance to technology. Research design, data and methodology: This study included 320 participants from generation Z in Jakarta who use digital bank and used a quantitative method with PLS-SEM. Results: This study explains how, in addition to usefulness, costs, and self-efficacy, resistance to technology has a direct effect on usage attitudes. Meanwhile, if the attitude of use is preceded by aspects of usefulness, self-efficacy, and awareness, resistance to technology will be felt indirectly. Conclusions: This demonstrated that most discussed factors, such as Ease-of-Use and security of use, are important for Generation Z users but no longer a major consideration in accepting digital banking. Aside from being more open to the use of technology in digital banks, Generation Z also desires a balance of technology services and benefits. The limitations of this study are that it excludes social variables, uses certain generations, and limits the research area to one large city, which can be expanded in future studies.

• Structural Engineering and Mechanics
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• v.85 no.3
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• pp.369-379
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• 2023

Reliability-Based Design Optimization (RBDO) is an appropriate framework for obtaining optimal designs by taking uncertainties into account. Large-scale problems with implicit limit state functions and problems with discrete design variables are two significant challenges to traditional RBDO methods. To overcome these challenges, this paper proposes a hybrid method to perform RBDO of structures that links Firefly Algorithm (FA) as an optimization tool to advanced (finite element) reliability methods. Furthermore, the Genetic Algorithm (GA) and the FA are compared based on the design cost (objective function) they achieve. In the proposed method, Weighted Simulation Method (WSM) is utilized to assess reliability constraints in the RBDO problems with explicit limit state functions. WSM is selected to reduce computational costs. To performing RBDO of structures with finite element modeling and implicit limit state functions, a First-Order Reliability Method (FORM) based on the Direct Differentiation Method (DDM) is utilized. Four numerical examples are considered to assess the effectiveness of the proposed method. The findings illustrate that the proposed RBDO method is applicable and efficient for RBDO problems with discrete and continuous design variables and finite element modeling.