• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.80-88
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• 2013

The present study was conducted to evaluate relationship between nonylphenol uptake rate and clearance rate of Ruditapes philippinarum, Corbicula japonica and Mytilus edulis. Variation of the temperature and body size of the bivalves was used to modulate clearance rate and nonylphenol uptake rate in this experiment. Clearance rate and nonylphenol uptake rate experiments were determined for two different size classes of the bivalves (R. philippinarum: 0.35, 0.73 g, C. japonica : 0.047, 0.1000g, M. edulis: 0.30, 0.37 g; mean flesh dry weight) and three different temperature regime (5, 13 and $18^{\circ}C$). Weight-specific clearance rate in all animal size and temperature ranges increased in the order of R. philippinarum, C. japonica and M. edulis. The weight-specific nonylphenol uptake rate did not show specific trend among species. The clearance rate and nonylphenol uptake rate generally decreased with animal size and increased with water temperature. For all three species nonylphenol uptake rate had a strong relationship with clearance rate. For a given clearance rate ranges, the nonylphenol uptake rate was in the order of R. philippinarum > C. japonica > M. edulis. The results suggest that water ventilation capacity of filter-feeding organisms is an important physiological factor controlling uptake rate of dissolved nonylphenol.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.347-360
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• 2020

In this study, the Bayesian state-space model was used for the stock assessment of the Blackfin flounder. In addition, effective measures for the resource management were presentedwith the analysis on the effectiveness of fisheries management plans. According to the result of the analysis using the Bayesian state-space model, the main biometric value of Blackfin flounder was analyzed as 1,985 tons for maximum sustainable yield (MSY), 23,930 tons for carrying capacity (K), 0.000007765 for catchability coefficient (q) and 0.31 for intrinsic growth (r). Also the evaluation on the biological effect of TAC was done. The result showed that the Blackfin flounder biomass will be kept at 14,637 tons 20 years later given the present TAC volume of 1,761 tons. If the Blackfin flounder TAC volume is set to 1,600 tons, the amount of biomass will increase to 16,252 tons in the future. Lastly, the biological effectiveness of the policy to reduce fishing effort was assessed. The result showed that the Blackfin flounder biomass will be maintained at 13,776 tons if the current fishing efforts (currently hp) level is set and maintained. If the fishing effort is reduced by 20%, it will increase to 17,091 tons in the future. The analysis on the economic effect of TAC showed that NPV will be the lowest at 1,486,410 won in 2038, 20 years after the establishment of 2,500 tons of TAC volume. If the TAC volume is set at 2,000 tons, NPV was estimated to be the highest at 2,206,522,000 won. In addition, the analysis on the economic effect of the policy to reduce the amount of fishing effort found that NPV will be 2,235,592,000 won in 2038, 20 years after maintaining the current level of fishing effort. If the fishing effort is increased by 10%, NPV will be the highest at 2,257,575 won even thoughthe amount of biomass will be reduced.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.2
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• pp.140-149
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• 2008

Recently, the need for accessing information from anywhere at any time has been a driving force for a variety of mobile applications. As the number of mobile applications increases rapidly, there has been a growing demand for the use of Service Oriented Architectures(SOA) for various applications. Mobile based SOA offers a systematic way to classify and assess technical realizations of business processes. But mobile has severly restricted range of utilizing services in computing environment and more, a mobile computer is envisioned to be equipped with more powerful capabilities, including the storage of a small database, the capacity of data processing, a narrow user input and small size of display. This paper present mobile adaption method based on SOA to overcome mobile restriction. To improve mobile efficient we analyzing mobile application requirement writing service specification, optimizing design, providing extended use case specification which test use case testing and testing service test case which derived from service specification. We discuss an mobile application testing that uses a SOA as a model for deploying discovering, specifying, integrating, implementing, testing, and invoking services. Such a service use case specification and testing technique including some idea could help the mobile application to develop cost efficient and dependable mobile services.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.962-968
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• 2013

Problem of greenhouse gases associated with global warming and the world rise in fuel oil prices due to the depletion of fossil fuel has attracted attention. For this reason, maritime transport business, has shown interest in green-ship technology to reduce the consumption of fuel and reduce greenhouse gas for environmental protection. Power system of the ship is one of the most important factors for safe operation. Therefore, at design of ship power system, most of existing vessel used comparative large capacity generator in order to respond peak load such as bow thruster, crane and etc. In the navigation of ship, marine generators most would be operated at low load operation. In the low load operation of the generation rate of 50% or less, the operation efficiency of the generator it deteriorated, to consume more fuel oil. It also, it means that adversely effect the life of the generator. In this paper, studied how to apply for a secondary battery in container ship that relatively frequent arrival and departure in port. As a result, in order to apply the secondary battery to increase the operating efficiency of the generator during the voyage, it was confirmed that it is possible to reduce fuel consumption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.382-392
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• 2017

This study analyzed the effect of an employee's psychological capacity(positive psychological capital), on perceived work overload, and explored how trust in supervisor moderated this relationship. In addition, we examined how positive psychological capital and perceived work overload influenced turnover intention. In doing so, we identified the antecedents of perceived work overload, and suggested ways to nurture positive psychological capital in organizations. Using survey data from 214 employees in the manufacturing industry in Korea, we found that positive psychological capital was negatively related to perceived work overload, and that the relationship was moderated by trust in supervisors. In addition, positive psychological capital was negatively associated while perceived work overload was positively associated with turnover intention. Results suggest the importance of understanding positive psychological capital given its crucial relationship with perceived work overload and turnover intention. The result also emphasizes the role that trust in supervisor plays, and the need to nurture employees' positive psychological capital in organizations.

• Management & Information Systems Review
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• v.32 no.4
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• pp.53-79
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• 2013

Social enterprises can be identified roughly as social purpose-oriented business ventures. They often fill the gaps left by governmental and commercial ventures in providing for certain vulnerable sectors of society. Though social enterprises often adopt market mechanisms in their organizational structures, their emphasis on particular social outcomes means that they intentionally pursue double/triple-bottom lines, thus distinguishing them from many traditional for-profit businesses. Among the Korean laborers, women have been hardest hit by the global economic crisis. As the movements have substantially been taken to strengthen women's economic activities in the recent years, many policies are formulated with these trends, connecting women's employment with social enterprises. This study focused on analyzing social enterprises to be friendly and to provide decent work to women. Data were collected from 491 social enterprises and 830 workers. The main results are as follows. First, the women's employment in social enterprises has accounted for a relatively high rate and the women's wage also is similar to men's one. Second, as for work conditions and types, most women have preferred irregular and non-managerial work. Thus, social enterprises have showed a positive response for the women's job opportunities, while social enterprises have had a negative one for enhancing the women's status at the labor market. In conclusion, social enterprises should institutionalize how to provide more stable working condition to women and to improve their's capacity.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.227-232
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• 2016

To test the effectiveness of using an energy storage system for frequency regulation, the Energy New Business Laboratory at KEPCO Research Institute installed a 4 MW energy storage system (ESS) demonstration facility at the Jocheon Substation on Jeju Island. And after the successful completion of demonstration operations, a total of 52 MW ESS for frequency regulation was installed in Seo-Anseong (28 MW, governor-free control) and in Shin-Yongin (24 MW, automatic generation control). The control system used in these two sites was based on the control system developed for the 4 MW ESS demonstration facility. KEPCO recently finished the construction of 184 MW ESS for frequency regulation in 8 locations, (e.g. Shin-Gimjae substation, Shin-Gaeryong substation, etc.) and they are currently being tested for automatic operation. KEPCO plans to construct additional ESS facilities (up to a total of about 500 MW for frequency regulation by 2017), thus, various operational tests would first have to be conducted. The high-speed characteristic of ESS can negatively impact the power system in case the 500 MW ESS is not properly operated. At this stage we need to verify how effectively the 500 MW ESS can regulate frequency. In this paper, the effect of using ESS for frequency regulation on the power system of Korea was studied. Simulations were conducted to determine the effect of using a 524 MW ESS for frequency regulation. Models of the power grid and the ESS were developed to verify the performance of the operation system and its control system. When a high capacity power plant is tripped, a 24 MW ESS supplies power automatically and 4 units of 125MW ESS supply power manually. This study only focuses on transient state analysis. It was verified that 500 MW ESS can regulate system frequency faster and more effectively than conventional power plants. Also, it was verified that time-delayed high speed operations of multiple ESS facilities do not negatively impact power system operations. It is recommended that further testing be conducted for a fleet of multiple ESSs with different capacities distributed over multiple substations (e.g. 16, 24, 28, and 48 MW ESS distributed across 20 substations) because each ESS measures frequency individually. The operation of one ESS facility will differ from the other ESSs within the fleet, and may negatively impact the performance of the others. The following are also recommended: (a) studies wherein all ESSs should be operated in automatic mode; (b) studies on the improvement of individual ESS control; and (c) studies on the reapportionment of all ESS energies within the fleet.

• International Commerce and Information Review
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• v.15 no.4
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• pp.267-286
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• 2013

The WCO Time Release Study (TRS) is a unique tool and method for measuring the actual performance of Customs activities. The ultimate aim of TRS is to improve the performance of the function being measured. To be more specific, TRS is used for identifying bottlenecks in the international supply chain and/or constraints affecting Customs release, assessing newly introduced and modified techniques, procedures, technologies and infrastructure, or administrative changes, establishing baseline trade facilitation performance measurement, identifying opportunities for trade facilitation improvements and estimating the country's approximate comparative position as a benchmark tool. The effective utilization methods of TRS for trade facilitation in Korea Customs Services are as follows ; Firstly, it is necessary to make every efforts to identify bottlenecks in border-related procedures and improve their procedures for continuous and more improved trade facilitation. Secondly, it is necessary to optimize and simplify export-related procedures using the TRS in exportation for efficiency of total international supply chain. Thirdly, it is necessary to make coordinated border management with main trading partners. Lastly, it is necessary to enhance Korea's international status to support underdeveloped countries in the field of trade procedures.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.4
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• pp.567-584
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• 2013

This study aims to explore an evolutionary path of the IT service industry in Fairfax County using the Cluster Adaptive Cycle model in economic geography. The analysis is based on detailed historical and industrial information obtained through a variety of data sources including local archival materials, economic census, and interviews. This study also performs a shift-share analysis during the period of 1990 to 2011. Using the adaptive cycle model, the local IT service industry is indicated by a trajectory of constant cluster mutation. The evolution of the local IT service industry has been closely related to federal government policy due to the regional specificity of the National Capital Region and the proximity of the Department of Defense. Although the economic downturn of the late 2000s, the local IT service industry has been notable resilience and adapted to a changing market and technological environment. This constant mutation of the local industry is resulted from not only high resilience which is based on the large government procurement market, the reinforcement of adaptive capacity of the local firms and the network of economic agents such as firm and supporting institutions, but also high flexibility of the knowledge-based service industry to a changing business environment.

• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.135-147
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• 2009

The world has witnessed the dramatic expansion of international construction markets during the last decades, particularly around the developing economies and energy resource-rich countries. However, despite the booming markets, the risks of emerging regions have also increased under the rapidly changing environments confronting the global contractors. Most of all, success in overseas business mainly depends on selecting the right market to enter. Accordingly, the right market selection requires global firms to carefully carry out the scientific market entry decision by evaluating country risks, market prospects, firm's capability, level of competition, and among others. This study aims at developing a market entry model by the use of real option analysis (ROA) and scenario planning, which addresses the corporate strategic flexibility against the uncertainties encompassing the overseas construction markets. Based on the suggested approach, global contractors are expected to make a better decision rather than a typically static approach in pursuing, postponing, or abandoning a prospective market to their capacity with a concurrent consideration of uncertainties as well as its option value.