• Journal of the Society of Naval Architects of Korea
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• v.47 no.5
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• pp.751-756
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• 2010

The rapid growth of IT technology has enabled ship automation systems to gain better functionality and safety with reduced costs and crew numbers. Nowadays, the remote maintenance services for the systems are required because a ship may be located in a very remote area. To provide the remote maintenance services, some issues such as how to collect the ship automation systems data, how to monitor a ship's data from onshore offices, how to get support from experts while sailing, and how to reduce the maintenance costs, should be addressed. In this paper, we propose a remote ship maintenance system for remote monitoring and diagnostics of ship automation systems, which is based on both a ship area network to integrate separate system networks and a ship-shore communication infrastructure to support a remote access using satellite communications. Finally, we present the function test to verify the applicability of the proposed system.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.195-200
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• 2021

In recent years, Vietnam's economic growth rate has been attributed to the growth of many well-managed industries within Southeast Asia. Among them is the civil construction industry. Construction projects typically take a long time to complete and require a huge budget. Many socio-economic variables and factors affect total construction project costs due to market fluctuations. In recent years, crucial socioeconomic development indicators of construction reached a fairly high growth rate. Also, most infrastructure and construction projects have a high degree of complexity and uncertainty. This makes it challenging to predict the accurate project price. These challenges raise the need to recognize significant factors that influence the construction price index of civil buildings in Vietnam, both micro and macro. Therefore, this paper presents critical factors that affect the construction price index using the fuzzy extent analysis process in an uncertain environment. This proposed quantitative model is expected to reflect the uncertainty in the process of evaluating and ranking the influencing factors of the construction price index in Vietnam. The research results would also allow project stakeholders to be more informed of the factors affecting the construction price index in the context of Vietnam's civil construction industry. They also enable construction contractors to estimate project costs and bid rates better, enhancing their project and risk management performance.

• Journal of the Korea Management Engineers Society
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• v.23 no.4
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• pp.125-141
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• 2018

As global competition is intensifying, companies are entering not only developed markets but also emerging and developing countries. In emerging and developing countries, business-to-governmental relations are an essential factor influencing the firm performance. The purpose of this research is to examine the effects of corporate political activities on firm performance. Using the BEEPS data developed by the EBRD and the World Bank, the effect of various bribery activities regarded as corporate political activities on the firm performance was examined. Also, the moderating effect of competition type on the firm performance was proved. As the results, the bribery contribution, which is a corporate political activity, has a positive effect on the firm performance. Specifically, when infrastructure bribery occurred, costs and sales were higher, and when permission bribery was granted, profits, costs, and sales were higher. In addition, the effect of bribery as a corporate political activity on firm performance is moderated by competition type. These findings have academic and practical implications for empirical analyzing of SMEs' firm performance, guidelines suggestion for entry into the other countries, generalization possibility of using credible data, developing and designing export support systems and programs. Finally, limitations of the research and future research directions were discussed.

• Environmental and Resource Economics Review
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• v.13 no.2
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• pp.219-243
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• 2004

Generally, electricity market has monopoly market structure because of need of enormous investment for infrastructure. However, the introduction of competition in network industry as electricity is a tendency of the world with decreasing the effects of economy of scale due to the advancement of technology. Now, electricity industry restructuring is in progress but the competition in electricity retail market is not in force yet in Korea. Whether a effective competition exist or not is very important to policy decision maker who drive restructuring, but there are small numbers of quantitative researches on that. In this study, we estimated the effectiveness of competition in the electricity retail market through switching costs. If switching costs are high, consumers actually can be locked in incumbent firm in spite of introduction of competition. Therefore switching is a critical factor to determine effectiveness of competition and to estimate the size of switching costs quantitatively can proffer the information about whether the competition in the electricity retail market is effective or not in the future. We estimated switching costs using consumer' stated-preference data by conjoint analysis. In according to estimation results, the cost of switching process is not so high, but the relative brand loyalty of an incumbent company is significantly high. And the price is considered as the most important factor choosing an electric service commodity. Based on the empirical results, it is possible to analyze the relationship between suppliers' competitiveness resulted from management efficiency and customers' switching possibilities. The paper therefore provides guidance for suppliers in deciding to enter into retail competition and for policy makers in introducing retail competition. And it has a significance of estimating the switching costs directly.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.9
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• pp.900-906
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• 2010

We analyse benefits and costs of investment on the assurance of aircraft design and development of related infrastructure. Although the discounted cash flow from the sales of aircrafts is found to be smaller than the amount of required investment, the net present value considering the effects of export increase, import substitution, and the accident cost reduction is very high. This justifies governmental investment, for the effects are not easily appropriated by private investors.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.51
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• pp.391-414
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• 2011

The advance into the overseas markets of domestic enterprises has been increasing continuously. Brazil, for domestic companies, has been emerging as the huge potential country in the development of markets and resources. According to the reports from World Bank and Brazil government, one of the biggest difficulties of businesses in Brazil for foreign enterprises is the lack of Transportation Infrastructure and high logistics costs. However, until now, there is no professional institute and systematic DB in Korea to provide the overall information of Brazil logistics or details oriented to enterprises' needs; furthermore, enterprises have the difficulties to gather or investigation the logistics information by themselves due to the constraints of language and budget. For these reasons, with the latest data, this study reviews the overall information of Brazil logistics environment and provides the status of Brazil logistics that is necessary for enterprises to advance into Brazil market. Also, this explains the reason for why Brazil has such a high logistics cost with the objective data. In addition, this paper carried out the benchmarking case study as an example of logistics strategy and plan in Brazil. This study can contribute to serve as useful information for domestic enterprises which planning or doing business in Brazil.

• Journal of Applied Reliability
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• v.16 no.4
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• pp.287-294
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• 2016

Purpose: Environment test support is urgent for small and medium defense companies in order to improve the reliability of weapons systems. Also, to reduce the burden of test costs, the voucher system must be strengthened. Quality assurance support should be accompanied by budget support. Methods: First of all, it is necessary to expand infrastructure for test equipment that suffers shortages by considering environmental test frequency and waiting periods to reduce the time required for environmental tests. Results: In regard to the environmental test, expansion for test equipment infrastructure, security of budget for the test, establishment of test plan, education and consulting support are required to resolve some limits of small and medium defense companies. Conclusion: Along with the opening of environmental test courses for industry operators, the expansion for consulting support projects of the defense industry support system is needed.

• International Journal of Railway
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• v.2 no.3
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• pp.99-106
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• 2009

Checks and tests before putting safety facilities into service as well as the results of these tests are essential, time consuming and may show great variations between each other. Economic constraints and the increasing complexity associated with the development of computerized tools tend to limit the capacity of the classic approval process (manual or automatic). A reduction of the validation cover rate could result in practice. This is not compatible with the French national plan to renew the interlocking systems of the national network. The method and the tool presented in this paper makes it possible to formally validate new computerized systems or evolutions of existing French interlocking systems with real-time functional interpreted Petri nets. The aim of our project is to provide SNCF with a method for the formal validation of French interlocking systems. A formal proof method by assertion, which is applicable to industrial automation equipment such as interlocking systems, and which covers equally the specification and its real software implementation, is presented in this paper. With the proposed method we completely verify that the system follows all safety properties at all times and does not show superfluous conditions: it replaces all the indoor checks (not the outdoor checks). The advantages expected are a significant reduction of testing time and of the related costs, an increase of the test coverage rate, an answer to the new demand of railway infrastructure maintenance engineering to modify and validate computerized interlocking systems. Formal methods mastery by infrastructure engineers are surely a key to prove that more safety is not necessarily more expensive.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.6
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• pp.3280-3298
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• 2019

Vehicular ad-hoc networks (VANETs) have become increasingly significant in intelligent transportation systems, they play a great role in improving traffic safety and efficiency. In the deployment of intelligent VANETs, intelligent vehicles can efficiently exchange important or urgent traffic information and make driving decisions. Meanwhile, secure data communication and vehicle's identity privacy have been highlighted. To cope with these security issues, in this paper, we construct an efficient anonymous authentication scheme with secure communication in intelligent VANETs. Combing the ElGamal encryption technique with a modified Schnorr signature technique, the proposed scheme provides secure anonymous authentication process for encrypted message in the vehicle-to-infrastructure communication model, and achieves identity privacy, forward security, and reply attack resistance simultaneously. Moreover, except the trusted authority (TA), any outside entity cannot trace the real identity of an intelligent vehicle. The proposed scheme is designed on an identity-based system, which can remove the costs of establishing public key infrastructure (PKI) and certificates management. Compared with existing authentication schemes, the proposed scheme is much more practical in intelligent VANETs.

• Korea Trade Review
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• v.44 no.5
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• pp.107-125
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• 2019

This study analyzes the effects of FDI on the global value chain (GVC) using participation and export value added using panel data from 2005 to 2016 for 63 countries. This study used the GLS method. Results are as follows: First, foreign direct investment had a positive impact on the global value chain (GVC) participation and export value added of non-OECD economies. Furthermore, tariff rates were more sensitive to non-OECD countries than OECD countries. In addition, logistics infrastructure had a negative impact on global value chain (GVC) participation and export value added, while developed countries, such as OECD countries, with good infrastructure, had a positive impact on non-OECD countries. Finally, research and development costs have been shown to play a very important role in non-OECD countries. This study found that various service sectors, such as research and development (R & D) as well as the general manufacturing industry, are expanding beyond two countries to form global value chains (GVC) in which several countries are connected from production to consumption.