• Journal of environmental and Sanitary engineering
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• v.3 no.2 s.5
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• pp.79-90
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• 1988

Untill to-day the disposal of municipal refuse in Korea is entirely depending on dumping the refuse into concave land except a few case that bring about the secondary pollution by generating insects, offensive odour and the dust blow which cause adverse effects to dwelling community in the vicinity. It is widely recognized since Korea is ready to be advanced nation must be carried out the proper way of refuse disposal as meet with the environmental standard and ready to accept by general public. Refuse disposal that is practiced by world wide is known as sanitary landfill although it bears some what the expensive construction and operation costs rather than the plain dumping. The following statement is the construction of sanitary landfill in brief. When one takes a look at the Unites States which has huge territory normaly carry out the refuse disposal by anaerobic improved landfill method while the country has limitted land is experimenting various types of landfill which bring about the earier reuse of completed landfill site and minimise the secondary pollution. The author of this article consider out of several landfill methods the semi aerobic landfill will be widely applied in Korea in coming day, the following article will elaborate little more about the semi aerobic method.

• Journal of Fisheries and Marine Sciences Education
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• v.15 no.1
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• pp.25-46
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• 2003

Marine recreational fishing is one of the most popular outdoor leisures and the number of people who are participating is sharply increasing more and more because of the increasement of their income and demand for marine leisure. However our ecosystem is inevitably facing marine environmental deterioration and overfishing. That is because marine recreational fisheries resources are common property resources which can be catched by anyone not willing to pay for them except their private costs as commercial fisheries. Also fisheries resources unlike other resources are renewable resources and have a critical zone. That is, having a possibility of severe depletion may result from high discount rates used by private exploiters. This paper is focused on that marine recreational fishing license system which is adopted in most advanced countries such as Canada and U.S. and included in deterioration. And money obtained by license fee should be spent for more improvement fishing culture and welfare for marine recreational fishers.This system can lower the high rates of discount and be useful to become a sustainable marine recreational fishing industry.

• Environmental Engineering Research
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• v.12 no.4
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• pp.157-175
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• 2007

The membrane biofilm reactor (MBfR) creates a natural partnership of a membrane and biofilm, because a gas-transfer membrane delivers a gaseous substrate to the biofilm that grows on the membrane's outer wall. $O_2$-based MBfRs (called membrane aerated biofilm reactors, or MABRs) have existed for much longer than $H_2$-based MBfRs, but the $O_2$-based MBfR is a versatile platform for reducing oxidized contaminants in many water-treatment settings: drinking water, ground water, wastewater, and agricultural drainage. Extensive bench-scale experimentation has proven that the $H_2$-based MBfR can reduce many oxidized contaminant to harmless or easily removed forms: e.g., ${NO_3}^-$ to $N_2$, ${ClO_4}^-$ to $H_2O$ and $Cl^-$, ${SeO_4}^{2-}$ to $Se^0$, and trichloroethene (TCE) to ethene and $Cl^-$. The MBfR has been tested at the pilot scale for ${NO_3}^-$ and ${ClO_4}^-$ and is now entering field-testing for many of the oxidized contaminants alone or in mixtures. For the MBfR to attain its full promise, several issues must be addressed by bench and field research: understanding interactions with mixtures of oxidized contaminants, treating waters with a high TDS concentration, developing modules that can be used in situ to augment pre-denitrification of wastewater, and keeping the capital costs low.

• Environmental Engineering Research
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• v.22 no.4
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• pp.393-400
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• 2017

One of the big problems facing municipalities is the management and control of urban flooding where urban drainage systems are under growing pressure due to increases in urbanization, population and changes in the climate. Urban flooding causes environmental and infrastructure damage, especially to roads, this damage increasing maintenance costs. The aim of the present study is to develop a decision support tool to identify the performance of storm networks to address future risks associated with climate change in the Middle East region and specifically, illegal sewer connections in the storm networks of Karbala city, Iraq. The storm water management model has been used to simulate Karbala's storm drainage network using continuous hourly rainfall intensity data from 2008 to 2016. The results indicate that the system is sufficient as designed before consideration of extra sewage due to an illegal sewer connection. Due to climate changes in recent years, rainfall intensity has increased reaching 33.54 mm/h, this change led to flooding in 47% of manholes. Illegal sewage will increase flooding in the storm system at this rainfall intensity from between 39% to 52%.

• Environmental and Resource Economics Review
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• v.23 no.3
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• pp.435-451
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• 2014

This paper attempts to evaluate an environmental regulation program which enforces installation of filtering equipment to reduce major air pollutants from used diesel vehicles. A real option model is presented to incorporate fuel cost uncertainty and irreversibility of emission-reducing investment. A finite-life option based on finite difference method is developed to consider the limited life expectancy of used vehicles. After taking into account social benefits from emission reduction and costs from decreasing fuel efficiency after the adoption of filtering technology, the result finds overall positive performance of the Pollution Reduction Program. However, the result suggests that the Program be designed to be more specific to vehicle types to improve program performance.

• Smart Structures and Systems
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• v.4 no.5
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• pp.641-653
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• 2008

This paper proposes a practical and realistic method to establish an optimal lifetime maintenance strategy for deteriorating bridges by considering the life-cycle performance as well as the life-cycle cost. The proposed method offers a set of optimal tradeoff maintenance scenarios among other conflicting objectives, such as minimizing cost and maximizing performance. A genetic algorithm is used to generate a set of maintenance scenarios that is a multi-objective combinatorial optimization problem related to the lifetime performance and the life-cycle cost as separate objective functions. A computer program, which generates optimal maintenance scenarios, was developed based on the proposed method using the life-cycle costs and the performance of bridges. The subordinate relation between bridge members has been considered to decide optimal maintenance sequence and a corresponding algorithm has been implemented into the program. The developed program has been used to present a procedure for finding an optimal maintenance scenario for steel-girder bridges on the Korean National Road. Through this bridge maintenance scenario analysis, it is expected that the developed method and program can be effectively used to allow bridge managers an optimal maintenance strategy satisfying various constraints and requirements.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1243-1249
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• 2010

Ground anchors can be good solution in large and deep excavation. Anchored supports generally provide larger workspace than strut supports and good performances. The major benefit provided by these anchored systems was the open excavation area created by eliminating horizontal or raked struts, which generally inhibit rapid construction within the site area. In loose soils, however, anchors are sometimes hard to get high pullout anchor capacity, so that the spacing of anchor both horizontally and vertically is frequently controlled, in which the construction costs of anchors are increased. In order to increase anchor capacity, therefore, conceptual introduction of the multi-strand anchor is presented in this paper. Also, this study shows an numerical study of predicting the load transfer of the multi-strand anchor and a beam-column analysis was performed by a Elastic-Plastic beam theory.

• Journal of Korea Port Economic Association
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• v.36 no.1
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• pp.23-40
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• 2020

This study examined the background of IMO environmental regulations and countermeasures of domestic and foreign liner shipping companies and also analyzed the additional cost and profitability of container shipping companies by implementation of IMO 2020, when the fuel oil is converted to low sulfur oil. The results show that the national flag carrier would incur significant additional costs when using low sulfur oil, which would worsen its profitability in all scenarios. These analysis results suggest that for regional shipping companies need reasonable BAF setting standards, which is flexible to the price of fuel oil and also seek ways to co-exist through mutual cooperation among oil refiners, shippers and shipping companies.

• Journal of Soil and Groundwater Environment
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• v.22 no.2
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• pp.10-16
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• 2017

Recently, the gap between demand and supply of natural aggregate has increased owing to the depletion of aggregate sources. Therefore, policy support is necessary for the stable supply of aggregate resources. Public and construction works experience problems when they do not receive a steady supply of aggregate. Further, instabilities in aggregate supply lead to increases in aggregate prices, and consequently construction costs. As a result, the likelihood of poor construction using low-grade aggregate increases. It is therefore crucial to put measures in place that deal with these issues. This study aims to reduce the load imposed by aggregate use on the environment by recycling soil dredged from sewage ducts to reduce the gap between supply and demand of fine aggregate. The dredged soil is assessed using an applicability test for quality characteristics and solidification with basic properties. This study aims to secure the safety of dredging soil and solidified objects through interior physical and chemical analyses and to utilize it as a base material for concrete solidification in the future.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.5
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• pp.517-527
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• 2014

As sewer flooding frequents due to localized and concentrated stormwater and increased non-permeable surface area after urbanization, building cities with sound water recycle and accordingly efficient management of rainwater is demanded. To do this, the existing sewage (including rainwater) fee imposition system should be philosophically evaluated. This study presents problematic issues of the existing domestic sewage fee imposition system considering the principle of sharing costs on the service of sewage and rainwater collection and treatment. Four methods to improve the existing sewage fee imposition system are suggested: 1) imposing stormwater fee according to Polluter Pays Principle, 2) clarification of the share of public sector, 3) reducing or exempting the sewerage fee for inhabitants reducing urban runoff by constructing their own rainwater management facilities, 4) imposing charge for discharging rainwater to sewers due to new development action. Short, mid, or long term planning for rainwater management is recommended considering the situation of each municipality.