• Journal of the Society of Naval Architects of Korea
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• v.42 no.3
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• pp.259-267
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• 2005

The effects of hull flexibility on shaft alignment are growing as ship sizes are increased mainly for container carrier and LNG carrier. In order to consider hull flexibility on a propulsion shafting system, standardization of ship service conditions is necessary because hull deformation is continuously variable according to ship service conditions. How to summarize ship service conditions is suggested based on practically applicable four viewpoints : hull, engine, loading and sea status. Effects of the external forces acting on a ship propulsion shafting system are generally commented. Several design criteria regulated by classification societies are pointed at issue which seems to have Insufficient technical background. A qualitative verification is carried out to point out the invalidity of the assumption of effective supporting position. In this work, an elastic nonlinear multi-supporting bearing system is introduced as a key concept of the elastic shaft alignment. Hertz contact theory is proved to be more proper one than projected area method in calculation of the nonlinear elastic stiffness of the bearing, The squeezing and oil film pressure calculations in the long journal bearing like an after stern tube bearing are recognized as a necessary process for elastic shaft alignment design.

• Journal of the Korea Convergence Society
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• v.12 no.3
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• pp.217-224
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• 2021

Based on the hyper-connectivity of the 4th Industrial Revolution, the paradigm shifts to the sharing economy. Didichuxing has already dominated the platform and is expanding its service to the TaaS 3.0 mobility industry. This paper aimed to suggest the direction of the domestic car-sharing industry and service improvement plan by analyzing Didichuxing. Korea is being cut off from the car-sharing industry, due to conflicts with existing industries and high regulations. It is necessary to balance the protection of existing industries and fostering new industries in the direction of negative regulations. In the future, it is also necessary to study how various fields of the sharing economy will convergence and develop.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.157-167
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• 2021

Cyberloafing is activity deviation at the workplace where employees intentionally avoid doing their job during working hours that results in a decrease in productivity. Particularly in the context of this study, cyberloafing activity is the usage of the Internet while working. Yet, studies on the antecedents and consequences of cyberloafing in the context of industrial revolution 4.0 and society 5.0 have not been conducted. This research used a purposive convenient sampling of 280 employees in the business services branches in Indonesia, particularly the representative business service branches located in some cities and regencies, including Yogyakarta City, Sleman Regency, and Bantul Regency (Special Region of Yogyakarta) and its surroundings. The results show 3 antecedents of cyberloafing and 1 consequence of cyberloafing which influence each other. Furthermore, these findings have filled the existing gaps regarding the antecedents and consequences of cyberloafing in service provider industries in the context of industrial revolution 4.0 and society 5.0. From the results of this research, it can be concluded that the five hypotheses proposed in this study are supported. The antecedents and consequences of cyberloafing have been tested and proven in this study as a contribution to science and technology.

• Journal of Distribution Science
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• v.20 no.4
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• pp.95-100
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• 2022

Purpose: This study aimed to investigate whether distribution and service companies maintained their accounting information quality and provided reliable information despite the economic changes occurring after the outbreak of the COVID-19 pandemic in Korea. The distribution industry has enjoyed increased demand as many companies expanded their untact distribution channels, including to online sales. However, as the pandemic drags on, their future prospects remain uncertain. Research design, data, and methodology: In this study, we define 2018-2019 as the "pre COVID-19 period" and 2020 as the "post COVID-19 period." An empirical analysis was performed using a regression model that includes POST, the independent variable, indicating the post COVID-19 period, and discretionary accruals(DA), a proxy for earnings management, as a dependent variable. Results: The analysis shows that the coefficient of POST is significantly positive (+) for the dependent variable DA. This finding suggests that distribution and service companies engaged in more earnings management during the post COVID-19 period than during the pre COVID-19 period, indicating their awareness of the uncertainty of future business performance as the pandemic persists. An additional analysis confirmed that smaller companies with fewer stakeholders and higher information asymmetry tend to engage more in earnings management than larger companies.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.1
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• pp.87-94
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• 2017

Many industrial accidents have occurred continuously in the manufacturing industries, construction industries, and service industries of Korea. Fatal accidents have occurred most frequently in the construction industries of Korea. Especially, the trend analysis of the accident rate and fatal accident rate is very important in order to prevent industrial accidents in the construction industries systematically. This paper considers forecasting of the accident rate and fatal accident rate with static and dynamic time series analysis methods in the construction industries. Therefore, this paper describes the optimal accident rate and fatal accident rate by minimization of the sum of square errors (SSE) among regression analysis method (RAM), exponential smoothing method (ESM), double exponential smoothing method (DESM), auto-regressive integrated moving average (ARIMA) model, proposed analytic function model (PAFM), and kalman filtering model (KFM) with existing accident data in construction industries. In this paper, microsoft foundation class (MFC) soft of Visual Studio 2008 was used to predict the accident rate and fatal accident rate. Zero Accident Program developed in this paper is defined as the predicted accident rate and fatal accident rate, the zero accident target time, and the zero accident time based on the achievement probability calculated rationally and practically. The minimum value for minimizing SSE in the construction industries was found in 0.1666 and 1.4579 in the accident rate and fatal accident rate, respectively. Accordingly, RAM and ARIMA model are ideally applied in the accident rate and fatal accident rate, respectively. Finally, the trend analysis of this paper provides decisive information in order to prevent industrial accidents in construction industries very systematically.

• International Area Studies Review
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• v.15 no.2
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• pp.125-150
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• 2011

As the economy grows, there is a concern that the economic development causes a productivity reduction because of the service intensive growth. However, the economy of developed countries encounter with the productivity growth as their economy grows, which phenomenon called Baumol's paradox. Oulton (1999, 2001) find out the reason of Baumol's paradox in a forward and backward chain effects. So, this paper is aimed at verifying the theory of Oulton (1999, 2001). Moreover, we test the difference effect between a consumer service and producer service input using a dummy variable. We use the Input-Output Table (1990, 1995, 2000, 2005) that is offered by the Bank of Korea to accomplish the purpose of our research that is represented above. We find out that the Korea's intermediate producer service inputs cause a multifactor productivity growth. That result is matched with the Oulton (1999, 2001)'s theory. But, the intermediate consumer service inputs don't have a significant effect on a multifactor productivity. The result of verifying the effect of intermediate producer service inputs among industries shows that the effects on manufacture industries are less than other industries.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.489-491
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• 2005

This paper presents the application study of substation automation protocol, IEC 61850 to digital relay (HiMAP). Especially, it implements the data modeling, ACSI definition, GOOSE, MSVCB and data service required in the existing digital relay. To verify the system performance, we develop the process emulator and HiMAP emulator, and describe the results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.3
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• pp.109-116
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• 2007

Entrepreneurship is considered as the main leadership creating enterprises and employment. However, in Korea empirical studies linking Korean entrepreneurial performances with her characteristics are rarely in existence. Current study focuses on Korean entrepreneurs in manufacturing, construction and other technologically intensive (MCOT henceforth) industries compared to entrepreneurs in service and other technologically less intensive (SOT henceforth) industries and to professional/technical wage workers and examines effects of human capital, demographic, and risk-taking characteristics on earnings. Education premium is higher for entrepreneurs in MCOT industries than for professional/technical workers, even though science and engineering diploma pays better in the latter, and that concentration in college causes more selection into the latter occupational family. In terms of education premium and effects of other characteristics SOT industry entrepreneurship and self-employment appear to be lower grade occupational families, even though there appear to be significant comparative advantages working in their selection.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.112-117
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• 2008

The Insulation, which is consist of the glass wool, mineral wool or perforated SUS plate, installed on the wall or under ceiling for the protecting heat and the blocking the noise of engine room area. In our shipyard, designing the structure model of insulation is hard and difficult, Because designed the insulation model is considered of any factors which are hull model properties of panel shape, direction and thickness and service of area. In this paper, We issue the way to utilize shape and direction of the hull model information and specific character of working space in engine room.

• International Journal of Reliability and Applications
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• v.8 no.2
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• pp.183-197
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• 2007

There is a growing trend for asset intensive industries to outsource maintenance services of their complex assets since outsourcing through service contract reduces upfront investments in infrastructure, expertise and specialised maintenance facilities. Estimation of costs for such contracts is complex and it is important to the user and the service providers for economic variability. The service provider's profit is influenced by many factors such as the terms of the contract, reliability of asset, and the servicing strategies, costs of resources needed to carryout maintenance. There is a need to develop mathematical models for understanding future costs to build it into the contract price. Three policies for service contracts are proposed in this paper considering the concepts of outsourcing maintenance service of assets to the service providers. Conceptual models are developed for estimating servicing costs of outsourcing through service contracts by considering time dependent failure mode.