• Journal of the Korea Concrete Institute
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• v.28 no.6
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• pp.673-683
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• 2016

In recent years, frequent terror or military attack by explosion, impact, fire accidents have occurred. Particularly, World Trade Center collapse and US Department of Defense Pentagon attack on Sept. 11 of 2001. Also, nuclear power plant incident on Mar. 11 of 2011. These attacks and incidents were raised public concerns and anxiety of potential terrorist attacks on major infrastructures and structures. Therefore, the extreme loading researches were performed of prestressed concrete (PSC) member, which widely used for nuclear containment vessel and gas tank. In this paper, to evaluate the blast resistance capacity and its protective performance of bi-directional unbonded prestressed concrete member, blast tests were carried out on $1,400{\times}1,000{\times}300mm$ for reinforced concrete (RC), prestressed concrete without rebar (PSC), prestressed concrete with rebar (PSRC) specimens. The applied blast load was generated by the detonation of 55 lbs ANFO explosive charge at 1.0 m standoff distance. The data acquisitions not only included blast waves of incident pressure, reflected pressure, and impulse, but also included displacement, acceleration, and strains at steel, concrete, PS tendon. The results can be used as basic research references for related research areas, which include protective design and blast simulation under blast loading.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.4
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• pp.95-100
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• 2007

Busan-port is world's fifth trading port and is playing an important role in medium of revenue expansion and civic growth of Busan metropolitan city. Therefore, Busan metropolitan city aims at establishment of maritime special city with sailing of popular election third times. But this sort of goal can be accomplished when job satisfaction of port's personnel concerned is elevated. So, the object of this study is to research on job satisfaction of Busan-port pier management corporation's employee. Through the examination of preceding studies, duty contents promotion remuneration control sense of responsibility colleague relation guarantee job office quantity working environment. tenure of office sex age education are used as factors of job satisfaction. The finding of this study are as follows; First, promotion and remuneration exert significant influence upon job satisfaction. Second, the job satisfaction of Busan-port Pier Management Corporation's Employee is pretty low.

• Journal of Navigation and Port Research
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• v.48 no.1
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• pp.62-77
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• 2024

In the maritime shipping industry, imbalance between supply and demand has persistently increased, leading to the utilization of blank sailings by major shipping companies worldwide as a key means of flexibly adjusting vessel capacity in response to shipping market conditions. Traditionally, blank sailings have been frequently implemented around the Chinese New Year period. However, due to unique circumstances such as the global pandemic starting in 2020 and trade tensions between the United States and China, shipping companies have recently conducted larger-scale blank sailings compared to the past. As blank sailings directly impact freight transport delays, they can have negative repercussions from perspectives of both businesses and consumers. Therefore, this study employed Poisson regression models and negative binomial regression models to analyze the influence of maritime freight rate determinants on shipping companies' decisions regarding blank sailings, aiming to proactively address potential consequences. Results of the analysis indicated that, in Poisson regression analysis for 2M, significant variables included global container shipping volume, container vessel capacity, container ship scrapping volume, container ship newbuilding index, and OECD inflation. In negative binomial regression analysis, ocean alliance showed significance with global container shipping volume and container ship order volume, the alliance with container ship capacity and interest rates, non-alliance with international oil prices, global supply chain pressure index, container ship capacity, OECD inflation, and total alliance with container ship capacity and interest rates.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.1-15
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• 2015

Before the advent of pasteurization and other microbiological controls in the dairy industry, milk product-borne diseases such as scarlet fever, typhoid fever, septic sore throat, and tuberculosis were globally widespread. Pasteurization was invented by Louis Pasteur, and it has been considered as one of the most effective ways to control milk product-borne diseases since the 20th century. Nevertheless, till date, various types of cheese in the EU, the USA, and other countries are made from unpasteurized milk as artisan cheese, following the specific food regulations of each nation. Furthermore, after the effectiveness of the Free Trade Agreement (FTA) negotiations between Korea and many nations, the import of various types of cheese made in different conditions and influenced by acidity, preservatives, temperature, competing flora, water activity, and salt concentration increased yearly. Hence, the objective of this review was to describe (1) the 60-day aging rule of cheese, (2) characteristics of the outbreaks linked to cheese manufactured from unpasteurized milk since 1998 to 2011 in USA, and (3) serious health risks from unpasteurized milk, to ensure food protection and safety and to use this basic information for risk assessment.

• Journal of Korean Society of Transportation
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• v.20 no.3
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• pp.149-158
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• 2002

For the purpose of preciously describing real time traffic pattern in urban road network, dynamic network loading(DNL) models able to simulate traffic behavior are required. A number of different methods are available, including macroscopic, microscopic dynamic network models, as well as analytical model. Equivalency minimization problem and Variation inequality problem are the analytical models, which include explicit mathematical travel cost function for describing traffic behaviors on the network. While microscopic simulation models move vehicles according to behavioral car-following and cell-transmission. However, DNL models embedding such travel time function have some limitations ; analytical model has lacking of describing traffic characteristics such as relations between flow and speed, between speed and density Microscopic simulation models are the most detailed and realistic, but they are difficult to calibrate and may not be the most practical tools for large-scale networks. To cope with such problems, this paper develops a new DNL model appropriate for dynamic traffic assignment(DTA), The model is combined with vertical queue model representing vehicles as vertical queues at the end of links. In order to compare and to assess the model, we use a contrived example network. From the numerical results, we found that the DNL model presented in the paper were able to describe traffic characteristics with reasonable amount of computing time. The model also showed good relationship between travel time and traffic flow and expressed the feature of backward turn at near capacity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1431-1438
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• 2015

According to the report from OECD, 80% of world trade quantity was influenced by standard, 50% of EU trade demand certification of forced standard. This leads to develop standard connected with R&D in most country and company worldwide. Recently, Technical standards have advantage of reduction of production cost and market dominating power. Standardization of construction technology has very important role that ouput of R&D refer to KS, national construction standards and it activates in the market. However, domestic construction research related to effectiveness of standadization fall short of expectation in comparison with manufacturing industry. This study present criteria that can analyze the performance and effectiveness in construction R&D project connected with standardization. And it applied domestic R&D cases (finished from 2000 to 2009), analyzes ouput of standadization and economic effect to verify the value of construcion technology standardization.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.4
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• pp.323-329
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• 2017

Nowadays, considering global warming and enhanced prohibition to discharge pollutants at sea, all of existing operation-ships must lead to the reduction of fuel consumption. International standards of International Maritime Organization and EU rules governing harbor pollutants are being strengthened. Therefore, ship-owners and operators are seeking ways to reduce $CO_2$, SOx, and NOx emissions. Although world trade continues to expand, total fuel usage for sea transport tends to diminish. However, ICS(International Chamber of Shipping) has set a goal of reducing $CO_2$ emissions from shipping by 50% until 2050. In addition, with respect to the Paris Climate Change Accord in 2015, IMO proposes to set up a reduction target of GHG emission from existing operation-ships. For setting up a reduction target of GHG from international maritime transport, "A data collection system for fuel consumption" will be introduced in the near future. In order to effectively reduce the use of fuel in a ship in accordance with the trend of compulsory fuel saving from operation ships, this paper suggested adoption of an Incentive-Penalty scheme based on Emission-Trading-Scheme, Carbon Tax, and basic calculation formula after verifying the EEOI level for a year.

• Environmental and Resource Economics Review
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• v.16 no.3
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• pp.549-574
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• 2007

This paper was intended to evaluate environmental policies of South Korea and compare its environmental sustainability with other Eastern Asian countries in terms of some sustainability measures. To meet the purpose, the paper is composed of three parts: a brief and critical review of Korea's current environmental policies, comparison of its sustainability with other Eastern Asian countries in terms of well-known environmental sustainability indices, and comparison in terms of a less well-known alternative measure. Korea's environmental policies as stipulated in "Green Vision 21", "Green Korea 2005" were evaluated in light of OECD EPRK 2006. Korea's environmental performance is then compared with other countries based on such environmental sustainability indices as EF, ESI, EPI and EVI. Unfortunately the well-publicized indices to measure sustainable development (SD) seem to fail in measunng SD and in providing comparability, because it does not base on the genuine concept of SD. Therefore, we tried to suggest an alternative measurement in terms of sustainability quantity (SQ), which is presented for South Korea and her major trading partners, such as USA, Japan and China.

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.699-707
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• 2013

With the increase in the trade volume between countries, the market of freight forwarders industry has been gradually growing. However, not only in Korea, with the number of global freight forwarders increasing, global competition has been increasingly fierce, and domestic freight forwarders are facing enormous challenges, therefore, the relevant policy sectors have carried out a series of supportive policies, while academics have conducted various researches. But most of them have focused on the current situation or the business model, and they could not get feedback on government support policies from enterprises. Using the AHP analysis, this study decided the priority of the government's ongoing supporting policies, compared the cognitive differences among of the companies of 3 different sizes, which was further verified using t-test. Then we compared the government support policies with the actual expectations of the companies to see if they matched on the basis of the previous results of this study, in order to help to strengthen the competitiveness of our freight forwarding industry.

• Economic Analysis
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• v.25 no.1
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• pp.34-65
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• 2019

This paper investigates the effects on Korean exports of demand in developed economies, and how these effects have changed since the global financial crisis. As a measure of import demand, we use import intensity-adjusted demand to take into account heterogenous import intensities across components of aggregate demand. Our estimation of a dynamic panel regression model reveals that Korea's exports to the G7 countries were elastic with respect to the import demand of these countries until the global financial crisis, but have shifted to become inelastic since. Furthermore, we separately estimate the effects of the different components of the G7 countries' aggregate demand (private consumption, public consumption, investment and exports). The results show that the decrease in private consumption in the G7 countries during the crisis had a significant impact in causing the decline in Korea's exports to them, but that the increase in their public consumption since the crisis has had a significant effect on driving increased Korean exports to them. The effects of the G7 countries' exports on Korea's exports to them remain positive and significant during both the pre- and post-crisis periods. The effects of the G7 countries' investments on Korea's exports are also positive and significant, but the positive effect has weakened since the crisis. Our findings suggest that the overall effect of changes in the G7 countries' import demand on Korea's exports to them has weakened compared to the pre-crisis period.