• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.11-12
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• 2005

With the great advances in process understanding, sensor and instrumentation technology and modelling capability it is important to ask what if any practical benefits can the lake manager and operator look forward to. Here, we examine some of the more important problems facing operators of drinking reservoirs, hydro-lakes and lakes used predominantly for recreation and the environment. In drinking reservoirs the main problems originate from increased loadings of nutrients leading to increased biomass and biomass that may give rise to toxins, of anthropogenic chemicals such as metals and synthetic organics and of pathogens of different types. Hydro-lakes are predominantly plagued by problems arising from low oxygen levels in the hypolimnion and in recreational and environmentally sensitive lakes the biggest challenge for the operator is to maintain an existing or establish a new trophic hierarchy or protect the water body from foreign species. The control variables that are at an operator's disposal are the choice of lake water level, the modification of the water colunm stratification via a de-stratification system, the modification of the lake flow path with flow intervention. curtains, intervention in the catchments to modify the loadings flowing into a lake, manipulation of the trophic chain with introduction of new species and chemical dosing, the latter being of marginal use in a large lake. Each of these options is cost effective under certain-circumstances. We endeavour to provide a users guide for their application and show how, especially new instrumentation and modelling methodologies may be used to achieve an effective intervention.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.342-347
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• 2015

Floating LNG is a new concept which is used as LNG regasification/receiving facility and for LNG production/export facility. LNG Floating Production Storage and Offloading(FPSO) concept will put vitality into marginal gas fields which were delayed because of excessive investment cost in the world. LNG Floating Storage Regasification Unit(FSRU) also provides commercially competitive and effective solutions to the areas where onshore infrastructure is not well established. LNG cargo containment system is one of the key functions for FLNG to store produced LNG on a floating structure. This paper presents a new technology related to a LNG containment system; a combined cargo containment system utilizing the advantages of iIndependent tank type and membrane system. Technical advantages have been validated through research work.

• Environmental and Resource Economics Review
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• v.17 no.4
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• pp.751-774
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• 2008

In this paper, we examine the institutional prices differences in the electricity and natural gas industries using unbalanced panel data from 1999 to 2001. The changing market structures following deregulation in both markets allow us to examine the institutional prices differences by ownership type, market structure and merger activities. Estimating the reduced form, after controlling both intrinsic characteristic (marginal costs) and external factors (demand), allows us to identify the extent to which specific factors are correlated with the price. Furthermore it allows us to identify systematic institutional price differences in both electricity and natural gas markets. Our estimation results suggest that the private firms in electricity markets are associated with higher prices than public firms after controlling for demand and cost. We further find that dual-product firms in the natural gas industry and the electricity industry are associated with lower rates than single product firms. These results provide a weak evidence of economies of scope in the dual-product firms. Our results finally suggest that merger activities in natural gas markets are associated with higher rates.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.1-12
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• 2016

Internet of Things (IoTs) technologies have been computerized information generated from a variety of objects and humans, and have been applied to various fields by connecting via the Internet. In order to compensate for the marginal characteristics of IoT smart devices, such as low-power, limited processing and capacities, combining IoT and cloud computing technologies is now established itself as one of the paradigms. In this paper, we look at the definition, features and services of IoT and cloud computing technology, and we investigate and analyze the conversing needs of IoT and could computing, existing conversion paradigms, convergence cases, and platforms. In results, there are challenges to be solved, even though the cloud technologies complement a number of restrictions of IoT and offer various advantages such as scalability, interoperability, reliability, efficiency, availability, security, ease of access, ease of use, and reduced cost of deployment. We analyze the new research issues of convergence paradigm, and finally suggest a research challenges for convergence.

• Journal of Environmental Policy
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• v.14 no.4
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• pp.63-101
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• 2015

Banking and borrowing under the ETS may affect the low carbon technology investment level. If the indirect implementation measures are allowed, firms can gradually adjust their carbon reduction costs between implementation periods based on their carbon reduction costs and emission price forecasts. This implies that banking and borrowing may reduce or increase the level of low carbon technology R&D investment. In an oligopoly market, the effects of the measures are quite different from the ones in a perfectly competitive market. This is because the indirect implementation measures can shift market competition in Cournot competition model. The effects of banking and borrowing on the carbon reduction R&D investments depend on emission reduction costs, marginal production costs, discount rate, initial free allocation, and the cost reduction effects of R&D investment.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.339-347
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• 2004

This paper asks the question: what choice of environmental policy instruments is efficient to reduce sulfur dioxide from stationary sources\ulcorner: In Korea, command and control has been a common way of controlling $SO_2-emissions.$ When compared to the non-incentive environmental policy instrument such as command and control, economic incentive environmental policy instrument has been the advantage of making polluter himself flexibly deals with in marginal abatement cost to develop environmental technology in the long view. Therefore, the application possibility of the incentive environmental policy instrument was studied in this research to realize the countermeasure for controlling of $SO_2-emissions.$ As a result, enforcement of the countermeasure such as flue gas desulfurizer by command and control would be suitable because power generation is performed by the public or for the public in source of air pollution and thus, economic principle is not applied to the polluter. In the source of industrial pollution, enforcement of fuel tax is found to be suitable for the countermeasure for the use of low sulfur oil in terms of the flexibility of demand for the price in the long tenn. For the permissible air pollution standards applicable to all air pollutant emitting facilities, enforcement of incentive environmental policy such as bubble, off-set, banking policy or tradeable emission penn its would be ideal in long terms according to the regional characteristics and the number and scale of air pollutant emitting facilities.

• Journal of Environmental Policy
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• v.7 no.3
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• pp.1-40
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• 2008

In this paper, I examine the welfare effects of various revenue-neutral tax reforms in the case of two vertically-related oligopolies(downstream and upstream), where the upstream industry is polluting. I show analytically when and how government can improve welfare by initiating various tax reforms, regardless of either the feasibility of a lump sum transfer or the availability of a tax on pollution. The profit wedge that is the difference between the unit price and the unit cost and the marginal environmental damages(MED) becomes important to decidethe direction of a tax reform and is crucial to determine the direction of welfare-improving tax-subsidy schemes. I also show that a tax on pollution(Pigouvian tax) is superior to a tax on intermediate good even in the case of vertically-related oligopolies, because the former always brings in positive welfare effect from the upstream firms' input substitutability, which a tax on intermediate good cannot provide. Some policy implications for 'reducing environmentally-harmful subsidies' are also discussed.

• Journal of Broadcast Engineering
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• v.13 no.3
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• pp.388-400
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• 2008

This paper introduces a cost-effective method fur improving anchor picture quality of a multiview video coding scheme that is mainly based on chroma compensation. Proposed method is applied to both INTER $16{\times}16$ and SKIP modes in only anchor P-pictures. By testing using JVT common test conditions, simulation results show that proposed method can obtain the average BD-PSNR gains fur U and V as 0.136 dB and 0.127 dB, respectively, while maintaining almost same performance for Y (luminance). For the range of low bit-rates, it is observed that average BD-PSNR gains of Y, U, and V are 0.141 dB, 0.494 dB and 0.525 dB, respectively. Necessary computational complexity is very marginal because the number of anchor P-pictures is only 4.18% in comparison with whole coded sequences, however it can be found that the proposed method can significantly improve the coding efficiencies of color components.

• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.31-41
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• 2006

The main purpose of this paper is to develop the practical method to estimate the congestion price in odor to overcome the difficulty of traditional microeconomics approach for demand and cost function concepts. In this paper, we estimate the theoretical congestion toll which reflecting the real traffic conditions such as a speed-density functions using a traffic engineering methods We calculates the optimal congestion toll based on the real traffic conditions assuming that the electronic road pricing (ERP) systems ave installed for the study road. After evaluating the various speed-density relationship methods. we found that the Drake model is best suited for the Gangbyeon Expressway Using the Drake model, the optimal congestion toll will be 94 to 3,255 Won for the traffic speed between 44km/h to 68 km/h based on wage rate method and 107 to 6,381 Won for the marginal substitution method for the Gangbyeon Expressway in city of Seoul, Korea.

• Plant Journal
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• v.9 no.1
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• pp.50-57
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• 2013

This study investigates the risks that can occur during the development stage of IPP project in developing countries. In case that ECA and MLA cannot participate due to poor credit rating of the country, the diversification of power purchaser in marginal states can be a great help to reduce both market risk and country risk at the same time. In case of thermal power plants and combined cycle power plants, the effect of performance degradation as time passed will be considered and expected profit of sponsors should be maintained. Recently, developing countries are expanding IPP projects to reduce the financing cost and Korean power companies are positively participating in IPP projects. Accordingly, the loss of Korean companies should be minimized by risk management through the risk mitigation methods of this study.