• International Journal of Automotive Technology
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• v.6 no.3
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• pp.269-275
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• 2005

The engine cooling system for a medium duty V6, 4.5 L diesel engine was modeled with a commercial code, GT-Cool in order to investigate the effect of controllable electric pump on the cooling performance and the fuel economy. The simulation results of the cooling system model with mechanical coolant pump were validated with experimental data. Two different types of electric pumps were implemented into the cooling system model and PID control for electric pump operation was incorporated into the simulation study. Based on the simulation result with electric pump, conventional thermostat hysteresis was modified to reduce pump operation for additional improvement of fuel economy, and then the benefit of electric pumps with modified thermostat hysteresis on fuel economy was demonstrated with the simulation. The predicted result indicates that the cooling system with electric pump and modified thermostat hysteresis can reduce pump power consumption by more than $99\%$ during the FTP 74 driving cycle.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.15-23
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• 2000

If a system such as a port and regional economy has a large boundary and complexity, the system's substance is considered as a black box, forecast accuracy will be very low. Futhermore various components in a port and regional economy exert significant influence on each other. To copy with these problem the form of structure models were introduced by using SD model. This study has the issue of simplifying the regional economic effects of the port as contributing to raising the regional income. The regional economic effects of port have various indirect ones except for this. So, SD(System Dynamics) was presented, and applied to simulate port and regional economy.

• Journal of Korean Port Research
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• v.14 no.4
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• pp.387-394
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• 2000

If a system such a port and regional economy has a large boundary and complexity, the system's substance is considered as a black box, forecast accuracy will be very low. Futhermore various components in a port and regional economy exert significant influence on each other. To copy with these problem the from of structure models were introduced by using SD model. This study has the issue of simplifying the regional economic effects of the port as contributing to raising the regional income. The regional economic effects of port have various indirect ones except for this. So, SD(System Dynamics) was presented, and applied to simulate port and regional economy.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.9-17
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• 1994

In this study, a shifting algorithm of CVT was suggested for the two(2) driving modes : (1) power mode and (2) economy mode. Shifting algorithm must be obtained to make the engine run on the optimum operating line for the desired performance of the vehicle. Optimum operating lines of the engine were obtained by connecting the shortest way of the iso-power lines for the power mode and by connecting the shortest way of the BSFC curves for the economy mode. Also dynamic model of CVT vehicle was derived considering the throttle and the brake operation. By using the shifting algorithm and the CVT vehicle model, numerical simulations were performed to estimate the performance of CVT. Simulation results showed that comparing the performance of the conventional 4-speed automatic transmission, acceleration performance of the CVT vehicle was almost same with the AT vehicle for the power mode and the fuel economy of CVT was 14% superior than that of AT for the economy mode.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.8
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• pp.93-101
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• 2021

The study aims to test the model of Yang et al. (2017) for the overall assessment of the transportation sector in the sharing economy and add some new elements on the benefits of customer loyalty from some previous studies that were not mentioned in Yang's model. This study will take examples from the two big brands of car-sharing apps in the sharing economy in Vietnam - Uber, and Grab. This research focuses on customer loyalty in the sharing economy with Uber and Grab as the transport sector in Ho Chi Minh City. Based on the survey data of 380 customers in Vietnam, the research results show that two independent factors positively impact commitment and satisfaction: social benefits and economic benefits. Simultaneously, economic benefit has a positive effect on satisfaction while trust benefit has a negative effect on commitment. Finally, commitment has a positive impact on customer loyalty in the sharing economy. As a result, companies in the sharing economy can identify which are the key factors that strongly influence customer satisfaction, commitment, trust, and loyalty to help managers to devise the appropriate solutions for promoting the strengths or overcoming limitations to contribute to perfecting and improving the quality of the company's services.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.5
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• pp.398-412
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• 2023

The Korean government is actively promoting the hydrogen industry as a key driver of economic growth. This commitment is evident in the 2019 hydrogen economy activation roadmap and the 2021 basic plan for hydrogen economy implementation. This study quantitatively analyzes the economic impact of the hydrogen economy using input-output analysis based on the Bank of Korea's 2019 input-output table, projecting its size by 2050. Four parts dealt with production-inducing, value-added creation, employment-inducing, and wage-inducing based on a demand-driven model. The results reveal that transportation had the most remarkable economic effect throughout the hydrogen economy, and production was the least. The hydrogen economy is projected to reach 71.2 trillion won by 2050.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.101-108
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• 2004

The physical factor having a great influence among components of making values of profit model in apartment houses is equilibrium change of house and this study suggests an alternative of remodelling. It sets profit models including model dividing household of large scale into that of small scale using value making factor of apartment house and spatial composition techniques and model integrating households of small scale and converting them into those of large scale and finds that its economy is good as over 'average', evaluative value of economy is reduced as discount rate increases and economy of remodelling is superior.

• Journal of Information Technology Services
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• v.20 no.5
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• pp.177-187
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• 2021

The global economy has been very difficult due to the recent impact of COVID-19. Korea is also pushing for strong quarantine policies such as K- quarantine and social distancing, but the economy is hardly recovering. In particular, the economic situation began to change rapidly depending on the export and domestic market, the public's interest in the economy increased, and companies became more sensitive. In order to estimate this rapidly changing economic situation, major advanced countries have also developed models that can periodically monitor the economy at the government level. Through this, by periodically reporting the economic trends, the public and companies can be aware of the economic trends to some extent. This study analyzed the cases of weekly business trends in advanced countries and developed a model of weekly economic activity suitable for Korea. To verify this, indices closely related to the economy such as mobility, industrial activity, face-to-face consumption, and psychology were discovered and estimated. As a result of the study, the weekly economic activity index was judged to be very useful in capturing short-term real economic activity. In the future, in order to secure the robustness and stability of the index and to increase the reflection of reality, model improvement and parameter estimation should be performed regularly.

• International Journal of Computer Science & Network Security
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• v.23 no.9
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• pp.29-36
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• 2023

Blockchain is an emerging technology that is used to address ownership, centrality, and security issues in different fields. The blockchain technology has converted centralized applications into decentralized and distributed ones. In existing sharing economy applications, there are issues related to low efficiency and high complexity of services. However, blockchain technology can be adopted to overcome these issues by effectively opening up secure information channels of the sharing economy industry and other related parties, encouraging industry integration and improving the ability of sharing economy organizations to readily gain required information. This paper discusses blockchain technology to enhance the development of insurance services by proposing a five-layer decentralized model. The Najm for Insurance Services Company in Saudi Arabia was employed in a case study for applying the proposed model to effectively solve the issue of online underwriting, and to securely and efficiently enhance the verification and validation of transactions. The paper concludes with a review of the lessons learned and provides suggestions for blockchain application development process.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.119-138
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• 2020

Unlike the era of manufacturing-oriented industrial economy in the past, the era of service economy has characteristics intangible goods center, knowledge universalization, and expansion of needs, and many things that are of the economy are changing. In the past, the change in the environment was not fast, so even after analyzing the changed environment and deriving the talent needed for the company, it was possible to maintain a talent for the organization for a long time, so it is not proactive to build and apply talent. It became difficult to manage effectively. Therefore, in this paper, we conducted a normative study for deriving a desirable talent model rather than a descriptive human resource model. Human resources image suitable for the modern service economy era, the modern economic society and modern spirit were analyzed and reflected. The model in which the two opposing members of the organization, managers and employees, interact intensely and balance dialectically. A desirable talent in a modern organization must play the role of a manager, and the management and talent models in a modern organization can be said to be connected to each other like the front and back sides of a coin. The philosophy of human resources was presented in five dimensions: human, historical, social, economic, and management. The human resource model from eight factors: mastery, rationality, wisdom, customer orientation, innovation, flexibility, autonomy, collaboration. This study suggested that general talent model may vary depending on the company's type, empirical follow-up studies are needed the talents in each company in the future.