• Journal of KIISE:Databases
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• v.37 no.6
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• pp.308-314
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• 2010

As the price of flash memory continues to drop and the technology of flash SSD controller innovates, high performance flash SSDs with affordable prices flourish in the storage market. Nevertheless, it is hard to expect that flash SSDs will replace harddisks completely as database storage. Instead, the approach to use flash SSD as a cache for harddisks would be more practical, and, in fact, several hybrid storage architectures for flash memory and harddisk have been suggested in the literature. In this paper, we propose a new approach to use flash SSD as an extended buffer for main buffer in database systems, which stores the pages replaced out from main buffer and returns the pages which are re-referenced in the upper buffer layer, improving the system performance drastically. In contrast to the existing approaches to use flash SSD as a cache in the lower storage layer, our approach, which uses flash SSD as an extended buffer in the upper host, can provide fast random read speed for the warm pages which are being replaced out from the limited main buffer. In fact, for all the pages which are missing from the main buffer in a real TPC-C trace, the hit ratio in the extended buffer could be more than 60%, and this supports our conjecture that our simple extended buffer approach could be very effective as a cache. In terms of performance/price, our extended buffer architecture outperforms two other alternative approaches with the same cost, 1) large main buffer and 2) more harddisks.

• Journal of Korea Port Economic Association
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• v.29 no.4
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• pp.1-25
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• 2013

The purpose of this paper is to estimate economic benefits for the investment of railway transshipment system with non-powered turntable. The freight transport by railway can have decided advantages over trucks in terms of energy efficiency, emissions and cost for certain freight movements, just as transportation in the metropolitan region can have great advantages over driving truck. But the freight transport by truck should gain significant mobility benefits from a freight railway system. Thus, the railway transshipment system with non-powered turntable which is coupled railway transport advantages with load transport advantages has been developed and used in the european countries. This research has conducted the empirical analysis, by calculating the investment of railway transshipment system with non-powered turntable. The key factor for the economic benefits for the non-powered turntable is the utilizing throughputs. This demand is influenced by the throughput in the railway transshipment system. The main results of this paper are as follows: railway transshipment system with non-powered turntable does not have economic benefit for investment. We recommend that the plan for investment has to be considered the modification.

• Environmental and Resource Economics Review
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• v.21 no.3
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• pp.595-625
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• 2012

Recently environment-friendly pellet boilers have interests as emissions of greenhouse gases are regulated internationally and energy security becomes more important to oil addicted countries including Republic of Korea. But the Korean market for pellet boilers is on the initial stage due to the high production costs relative to other conventional boilers. Hence the Korean government has supported financially and promoted the pellet boiler business. In this sense, it would contribute market stratergy and effective promotion policy for both of the government and private companies if we can forecast market shares of pellet boilers appropriately. For this purpose, this study surveyed potential consumers' preferences on pellet boilers among various alternatives using a choice experiment reflecting intangible costs. As the market share of new technology increases, intangible costs decline. According to different intangible cost scenarios, we experimented people's preferences on oil, gas, electric, and pellet boilers. A multinomial logit model was employed to estimate coefficient parameters of common attributes for various alternative boilers. Based on the estimates, we forecasted market shares of individual boilers. We found that as intangible costs decline, the market share of pellet boiler increase substantically while market shares of electric and gas boilers decrease dramatically. The market share of oil boiler did not change significantly. Meanwhile, as people are more rich, more educated, and exposed to advertisement on pellet boilers, the likelihood of choosing the pellet boiler increases.

• Quality Improvement in Health Care
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• v.7 no.2
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• pp.190-202
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• 2000

Background : The objectives of this study were to examine patients' satisfaction with the DRG based payment method and its association with their awareness of the method, to examine patient reported changes in doctors' caring attitude, level of their out-of-pocket payments, providers' acceptance of patients' request for additional services after the program, and to examine changes in service utilization recorded in medical records. Method : One hundred-four patients who had cesarean sections before and after the demonstration program at two hospitals located in Seoul participated in the study. Patients were surveyed before discharges when their charges were finalized. Their medical records were reviewed as well to collect data for service utilization during hospital stays. The association between patients' satisfaction with the payment method and their awareness of the method was analyzed by ${\chi}^2$-test, and the significance of changes in providers' acceptance of patients' request for additional services and service utilization after the program were examined by ${\chi}^2$-test and t-test, respectively. Results : A large proportion of patients did not know of the DRG based payment method at the time of survey and a significantly larger proportion of patients who came to the hospitals with the knowledge satisfied with the method. About the same proportion of patients reported improvement and deterioration in doctors' caring attitude compare to the previous hospitalizations and a similar result was found concerning out-of-pocket payments. Providers' acceptance of patients' request for medication, PCA and painless delivery decreased significantly after the program whereas the acceptance for additional hospital days and laboratory and radiology tests did not. Length of stay, the numbers of days on antibiotics and antianemic medication, and the number of blood tests decreased significantly after the program, however, decreases in the rate of antianemic medication and the number of urine analyses were not statistically significant. Re-operation, in-hospital death, and complications were not observed before and after the program. Conclusion : The study findings indicated a need for better patient education and publicity about the newly introduced payment method to improve their satisfaction with the system. Other study findings concerning service utilization and quality of care indicators were consistent with the government funded evaluation studies.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.4 s.31
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• pp.21-26
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• 2004

Annually repeated flood damage is bringing about the rapid increasement of the loss of human lives and properly, and the enormous social cost for the restoration work is required. The annual amount of flood damage caused by the abnormal climate is reached about 1% of GDP, so more effective management of the flood control operation is needed to prevent the repetitive flood occurred same region. Also, the systematic planning and management or river improvement works are keenly required for the more effective execution of government working budget that expense to recover or to prevent the flood damage. The several organizations of government - Ministry of Construction & Transportation, Ministry of Government Administration and Home Affair, Ministry of Agriculture and Forestry, Ministry of Environment, Ministry of Science & Technology, Korea Meteorological Adminstration and so on - are promoting the flood prevention operations, but those promotion system makes it difficult to maintain the consistency of works. In this study, we try to develop the Web-GIS system prototype that will be able to effectively manage the nationwide river improvement works and to establish a framework that will be able to maintain the consistency of river improvement works. To achieve the study goals, we analysed current system of flood prevention operations, gathered related documents, had interviews with many government employees, and developed the Web-GIS system prototype.

• Journal of Navigation and Port Research
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• v.36 no.1
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• pp.21-26
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• 2012

Recently, vessel hijacking by pirates has been a big issue around the world. For example, the hostages of VLCC "SAMHO Dream" were released for a large sum of ransom. On January 20, 2011 "SAMHO Jewelry" succeeded releasing all of the 21 crews on the vessel by attacking the pirates in international waters for the first time since the founding of the Naval Force. Furthermore, the "HANJIN Tianjin" crews evacuated to the Citadel promptly and were rescued by the navy. As hijacking of Korean vessels by pirates is increasing, various safety measures must be implemented. As a matter of fact, the standard for ship's facilities has been partially revised and setting up an evacuation shelter on all vessels sailing dangerous zone has been reinforced. This research aims to discuss crew Citadel installation on vessels intended for long haul. In addition, it will look at measures against potential gas flow in the event of pirate armed attacks and fire outbreak onboard a vessel. It will also assess the optimal number of crew Citadels theoretically. Lastly, the optimal number of shelters in the event of fire outbreak will be discussed based on an FDS simulation.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.475-482
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• 2019

The increase in human use and activity in the oceans is leading to marine pollution and habitat destruction. As a result, in particular, marine animals with a long life cycle and small population are threatened with extinction. Thus, the Korean government designated 11 artificial habitats, such as aquariums and marine museums, as Ex-situ conservation institutions to preserve endangered marine life in 2010. However, studies on the significance and economic value of Ex-situ conservation institutions providing marine life conservation services have not been conducted. Thus, the purpose of this study was to estimate the public's quantitative support for the operation policy of Ex-situ conservation institutions, which is a management method for the protection and propagation of marine animals in Korea. To achieve this, the economic value of the marine animal conservation role of the National Maritime Museum was estimated, operated as an Ex-situ conservation institution for the preservation of green turtles in Korea. By using the representative non-market valuation method for public goods known as the contingent valuation method (CVM), the economic value of the Ex-situ conservation institution (National Maritime Museum) was estimated at approximately 41.8 billion won to a maximum of 78.1 billion won. The results of this study can be applied as basic data for marine animal management policymakers in establishing efficient management plans for endangered marine animals in Korea's coastal waters.

• The KIPS Transactions:PartD
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• v.12D no.3 s.99
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• pp.461-470
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• 2005

This paper suggests a new policy for consolidating a company's profits by segregating the clients using the contents service and allocating the media server's resources distinctively by clusters using the cluster analysis method of CRM, which is mainly applied to marketing. In this case, CRM refers to the strategy of consolidating a company's profits by efficiently managing the clients, providing them with a more effective, personalized service, and managing the resources more effectively. For the realization of a new service policy, this paper analyzes the level of contribution $vis-\acute{a}-vis$ the clients' service pattern (total number of visits to the homepage, service type, service usage period, total payment, average service period, service charge per homepage visit) and profits through the cluster analysis of clients' data applying the K-Means Method. Clients were grouped into 4 clusters according to the contribution level in terms of profits. Likewise, the CRFA (Client Request Filtering algorithm) was suggested per cluster to allocate media server resources. CRFA issues approval within the resource limit of the cluster where the client belongs. In addition, to evaluate the efficiency of CRFA within the Client/Server environment the acceptance rate per class was determined, and an evaluation experiment on network traffic was conducted before and after applying CRFA. The results of the experiments showed that the application of CRFA led to the decrease in network expenses and growth of the acceptance rate of clients belonging to the cluster as well as the significant increase in the profits of the company.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.135-145
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• 2017

The purpose of this study is to present meaningful information and policy implications concerning the determinants of royalties to the government-funded research centers and agencies. These groups are responsible for policies encouraging technology transfer from the public sector to the private sector. To identify key determinants of royalties in technology transfer, this study conducted AHP survey analysis (Survey period: 01/10~31/10, 2016) of 85 companies which were participants of the R&D project "Next Generation BioGreen21" of R.D.A in the "N"center from 2011 to 2015. Research results show that the critical factors include: 1)Technical considerations for determining the profitability of the technologies, 2)The interest and willingness of the management group, 3)Necessity and urgency of technology transfer. These findings suggest three main policy implications. First, the government-funded research centers and agencies should develop technologies that help companies improve their commercialization as well as the profitability in the near future. Second, government-funded research centers and agencies should consider reducing the administrative burden of the royalty payment for private companies. Third, public R&D projects should reflect the proper research schedule for technology development on the basis of the R&D time span of companies which transfer technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.543-548
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• 2017

This paper examines the effects of strong corporate governance for listed companies in accessing capital markets from the point of view of the weighted average cost of capital. Results found that corporate governance had a significant negative(-) relation to the weighted average cost of capital. This finding is consistent with previous research and implies that the higher shareholder ownership and foreign ownership have confidence in the financial information of the company, and therefore, risk is reduced for investors. This results in lower expected rates of return and companies will pay a lower cost of capital. Second, tax evasion had a positive effect(+) on the weighted average cost of capital. The low quality of corporate accounting information is expected to increase tax avoidance. Accordingly, this results in increased risk. If the required rate of return is high in its impact,it leads to increased capital costs. In addition, corporate governance and tax avoidance factors showed a negative affect (-) on the weighted average cost of capital. Corporate governance plays an important role in tax avoidance and the weighted average cost of capital, and strong corporate governance reducesthe impact on tax avoidance. In addition, the weighted average cost of capital in capital markets showed the reducing effect.