• 한국자동차공학회논문집
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• 제20권6호
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• pp.46-51
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• 2012

Fuel Cell Hybrid Vehicles (FCHVs) have become a major topic of interest in the automotive industry owing to recent energy supply and environmental problems. Several types of power management strategies have been developed to improve the fuel economy of FCHVs including optimal control strategy based on optimal control theory, rule-based strategy, and equivalent consumption minimization strategy (ECMS). The ECMS is applied in this study. This strategy is based on the heuristic concept that the usage of the electric energy can be exchanged to equivalent fuel consumption. This strategy is known as one of the promising solutions for real-time control of hybrid vehicles. The ECMS for an FCHV is introduced in this paper as well as the equivalent fuel consumption parameter. The relationship between the battery final state of charge (SOC) and the fuel consumption while changing the equivalent fuel consumption parameter is obtained for three different driving cycles. The function of the equivalent fuel consumption parameter is also discussed.

• 유통과학연구
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• 제19권3호
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• pp.61-70
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• 2021

Purpose: This paper reviews the attitudes of consumers related to the consumption crisis response strategy (i.e., defensive vs. receptive) that companies implement during crises. Research design, data, and methodology: We discuss the interaction between the crisis response strategy and the consumption crisis type (i.e., corporate ability vs. corporate social responsibility). We used SAS ver. 9.4 software to analyze the results. We applied a 2 × 2 intergroup experimental design to our sample of subjects, who were undergraduate and graduate students at a university in Seoul, South Korea. The three experimental variables considered were the entity's risk response strategy, the crisis type, and public relations strategy. The experiments were conducted by presenting a hypothetical scenario to eight groups. Prior to this experiment, five preliminary surveys were conducted to determine the three variables just mentioned. Preliminary surveys were conducted on the basis of these criteria. For eight selected product lines, 320 undergraduates were required to enter the product lines that are frequently used in the assessment center up to the fourth priority. Results: Analysis of variance revealed that experiments related to crisis response strategy, type of enterprise crisis, and type of public relations message were successful. Conclusions: Our results verify the impact of different types of social initiatives on distribution marketplaces.

• 해양환경안전학회지
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• 제28권3호
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• pp.451-458
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• 2022

In Korea, five major ports have been designated as sulfur oxide emission control areas to reduce air pollutant emissions, in accordance with Article 10 of the "Special Act on Port Air Quality" and Article 32 of the "Ship Pollution Prevention Regulations". As regulations against vessel-originated air pollutants (such as PM, CO2, NOx, and SOx) have been strengthened, the Ministry of Oceans and Fisheries(MOF) enacted rules that newly built public ships should adopt eco-friendly propulsion systems. However, particularly in diesel-electric hybrid propulsion systems,the demand for precise control schemes continues to grow as the fuel saving rate significantly varies depending on the control strategy applied. The conventional Power Take In-Power Take Off(PTI - PTO) mode control adopts a rule-based strategy, but this strategy is applied only in the low-load range and PTI mode; thus, an additional method is required to determine the optimal fuel consumption point. The proposed control method is designed to optimize fuel consumption by applying the equivalent consumption minimization strategy(ECMS) to the PTI - PTO mode by considering the characteristics of the specific fuel oil consumption(SFOC) of the engine in a diesel-electric hybrid propulsion system. To apply this method, a specific fishing vessel model operating on the Korean coast was selected to simulate the load operation environment of the ship. In this study, a 10.2% reduction was achieved in the MATLAB/SimDrive and SimElectric simulation by comparing the fuel consumption and CO2 emissions of the ship to which the conventional rule-based strategy was applied and that to which the ECMS was applied.

• KIEAE Journal
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• 제12권1호
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• pp.119-125
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• 2012

The objective of this study is to evaluate the electric lighting energy consumption carried out by Daysim program. A comparison between the measurement and simulated exterior global horizontal illuminance shows differences about 10% and it is very similar to the measurement. The interior illuminance simulated by Daysim are 18.9% lower than the measurement and simulated lighting energy consumption is 10% lower than the measurement. Corrected annual lighting energy simulation results show that the best case is the combination of occupancy switch-off and dimming system with automatic controlled blinds (E-3). In case of no blinds, it occasionally derives the minimum lighting energy consumption but it causes the glare, so we need to be careful for choosing the control strategy. For the overcast sky, the lighting energy consumption is not changed significantly by control strategy while the lighting energy in the clear sky is changed noticeably. So we must know the right strategy for each case to control the electric lights and blinds.

• 대한가정학회지
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• 제45권7호
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• pp.119-129
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• 2007

The purposes of this study were to explain consumer attitude and purchasing behavior, and coping strategy considering consumption emotions of technology and individual characteristics associated with high-tech products. The results of this study were as follows: consumer attitude was found to be somewhat favorable and a half of the respondents had some purchasing experience of high-tech products. Many consumers were more likely to perceive consumption emotion and some of coping strategies were found to be preferred to others. Then consumer attitude was found to be significantly influenced by some of the consumption emotion, while other individual characteristics were found to be insignificant. In addition, the purchasing experience was found to be significantly influenced by consumer attitude, marital status and education. Finally, each kind of consumption emotion might have a relation to several coping strategies.

• 설비공학논문집
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• 제16권6호
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• pp.574-583
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• 2004

In this study, the operation strategy of the radiant floor cooling is evaluated in terms of indoor environmental conditions and energy consumption through simulations using the TRNSYS comparing the existing cooling operation. The operation strategy during continuously operated for cooling is proposed that a representative room had additional equipments and other rooms were operated with only a radiant floor cooling system and that system and control method for cooling are varied with period while intermittently operated for cooling. Specifically, when there are no people in the room, rooms were operated by only radiant floor cooling system using cooling storage and when people are occupied, rooms were operated by dehumidification and supplementary cooling device with radiant floor cooling system. The results of this study show that proposed operation strategy can stably maintain the set room air temperature and can reduce the energy consumption compared to the existing cooling method during continuously operated for cooling. While intermittently operated for cooling, the difference of set room air temperature by proposed operation strategy does not happen, satisfying comfort standards and the radiant floor cooling can expect to supply stable electric power because of decreasing demand for peak electric power of energy consumption.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권10호
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• pp.4025-4041
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• 2020

Mobile edge computing (MEC) is capable of providing services to smart devices nearby through radio access networks and thus improving service experience of users. In this paper, an offloading strategy for the joint optimization of computing and communication resources in multi-user and multi-MEC overlapping scene was proposed. In addition, under the condition that wireless transmission resources and MEC computing resources were limited and task completion delay was within the maximum tolerance time, the optimization problem of minimizing energy consumption of all users was created, which was then further divided into two subproblems, i.e. offloading strategy and resource allocation. These two subproblems were then solved by the game theory and Lagrangian function to obtain the optimal task offloading strategy and resource allocation plan, and the Nash equilibrium of user offloading strategy games and convex optimization of resource allocation were proved. The simulation results showed that the proposed algorithm could effectively reduce the energy consumption of users.

• Asian Journal of Business Environment
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• 제5권4호
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• pp.59-66
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• 2015

Purpose - The aim of the study is to analyze the impact of the European Union's (EU) focus on innovation and consumption, after the EU Eastern enlargement, on trade, investment, and technology cooperation patterns of Korea to formulate a pan-European marketing strategy, with a special emphasis on the mobile phone industry. Research design, data, and methodology - This study compares the intersection of the pivotal areas in the markets in the "post-new normal" era to identify outlets to commercialize development and innovation in this region. The EU would like to realize potential trade and investment opportunities with the Central European Economic Community (CEEC) from this enlargement. Results - The study analysis suggests a positive impact for innovation and consumption from the EU Eastern enlargement on trade, investment, and technology cooperation patterns of Korea to formulate a pan-European marketing strategy with a special emphasis on the mobile phone industry or motorcar e-strategy. Conclusions - Due to the evolving close interdependencies some hubs have emerged between regional, small markets and the central, larger ones such as Germany and France.

• 한국유기농업학회지
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• 제20권1호
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• pp.1-19
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• 2012

The purpose of this study is to analyze consumption of homemade organically processed food (HOPF), and to derive directions for consumption promotion of HOPF. A survey was conducted for quantitative analysis regarding consumption. This study used an Ordinal Logistic Regression Model to derive more significant results in analyzing factors of consumption. The findings was that younger consumers with high income are more likely to purchase HOPF. And those consumers with high price and quality contentment are more likely to purchase HOPF. And contentment with certification institutions and improvement of health have a significant positive relationship with consumption. Consumers were found to pay 51 percent more for HOPF than for non-HOPF products. This level show that the current level of price premium for HOPF is 51 percent higher than their desired level. In order to reduce the price premium for HOPF, effective policy programs should be developed. A targeted market strategy to sell HOPF to younger consumers with high income is needed to boost consumption. A strict certification management system should be established to enhance consumer reliability in HOPF.

• Advances in Automotive Engineering
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• 제1권1호
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• pp.105-121
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• 2018

The hybrid electric powertrain is a robust solution that allows for major improvements in both fuel economy and emission reduction. In the present study, a through-the-road hybrid vehicle model with an electric motor driving the rear axle and an Internal Combustion Engine (ICE) driving the front axle has been constructed. We then present a systematic method for the determination of a real time applicable optimal Energy Management Strategy (EMS) for a hybrid road vehicle. More precisely, we compare the performance of rule-based EMS strategies to an optimization-based strategy, namely ECMS (Equivalent Consumption Minimization Strategy). The comparison is conducted in parallel with a parameterization of the size of the internal combustion engine and the implementation of a Continuously Variable Transmission (CVT) that allows following the line of best fuel economy. For the FTP-75 driving cycle, the constrained engine On-off control algorithm is shown to offer a 28% improvement potential of fuel consumption compared to the conventional internal combustion engine while the ECMS strategy achieves an improved potential of nearly 33%.