• Journal of Korean Society of Water and Wastewater
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• v.26 no.2
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• pp.191-199
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• 2012

Rainwater harvesting systems (RWHS), one of measures for on site rainwater management, have been promoted by laws, regulations and guidelines and have been increased. However, more evaluation of economic feasibility on RWHS is still needed due to seasonal imbalance of rainfall and little experiences and analysis on design and operation of RWHS. In this study, we investigated tank capacity of RWHS to secure economic validity considering catchment area and water demand, which is affected by building scale. Moreover, sensitivity analysis was performed to examine the effect of design factors, cost items and increase rate of water service charge on economic feasibility. The BCR (benefit cost ratio) is proportional to the increase in tank capacity. It is increased steeply in small tank capacity due to the effect of cost and, since then, gently in middle and large tank capacity. In case of 0.05 in the rate of tank volume to catchment area and 0.005 in water demand to catchment area, BCR was over one from the tank capacity of 160 $m^{3}$ taking into account of private benefits and from the tank capacity of 100 $m^{3}$ taking into account of private and public benefits. Sensitivity analysis shows that increase of water demand can improve BCR values with little cost so that it is needed to extend application of rainwater use and select a proper range of design factor. Decrease of construction and maintenance cost reduced the tank volume to secure economic validity. Finally, increase rate of water service charge had considerable impact on economic feasibility.

• The Transactions of the Korea Information Processing Society
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• v.4 no.8
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• pp.2080-2091
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• 1997

It is generally recognized that Video On Demand (VOD) service will become a promising interactive service in the emerging broadband integrated services digital networks. A centralized VOD system, all programs are stored in a single VOD server which is linked to each user via exchanges, is applicable when a small number of users enjoys the VOD service. However, in case of large service penetration, it is very important to solve the problems of bandwidth and load concentrating in the central video server(CVS) and program transmission network. In this paper, the architecture of the video distribution service network is studied, then a traffic characteristics and models for VOD system are established, and proposed program allocation method to video servers. For this purpose, we present an analysis of program storage amount in each LVS(Local Video Server), transmission traffic volume between LVSs, and link traffic volume between CVS and LVSs, according to changing the related factors such as demand, the number of LVS, vision probability, etc. A method for finding out storage capacity in LVSs is also presented on the basis of the tradeoffs among program storage cost, link traffic cost, and transmission cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1715-1724
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• 2015

This study assessed the long term structure of forest age groups and the possibility of a domestic wood supply based on the wood industry buildup master plan. Wood is assumed to be supplied by main cutting, renewal, cutting damaged trees and thinning. The cohort equation was applied to identify the dynamic changes in forest area according to the age groups. The sixth age group, which composed of only 7.7% in 2010, is expected to comprise 73% of the total production land. The area distributions of the other age groups are expected to be between 5.3 - 5.6%. Consequently, the production volume from main cutting accounts for approximately 93 - 95% of the total production. The production volume from thinning, which depends on the area of the second and third age groups, will be decreased gradually. When the volume of domestic timber supply was compared with the timber demand from a previous study, the self-sufficiency of timber demand will be approximately 83% in 2050.

• Journal of Korean Society for Geospatial Information Science
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• v.1 no.1 s.1
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• pp.117-125
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• 1993

GSIS is a system that contains spatially referenced data that can be analyzed and converted to information for a specific set of purpose, or application. The key feature of a GSIS is the analysis of data to produce new information. The current emphasis in the transportation is to implement GSIS in conjunction with real time systems Requirements for a transportation GSIS are very different from the traditional GSIS software that has been designed for environmental and natural resource applications. A transportation GSIS may need to include the ability for franc volume, forecasting, pavement management A regional transportation planning model is actually a set of models that are used to inventory and then forecast a region's population, employment, income, housing and the demand of automobile and transit in a region. The data such as adminstration bound, m of landuse, road networks, location of schools, offices with populations are used in this paper. Many of these data are used for analyzing of traffic volume, traffic demand, time of mad construction using GSIS.

• The Journal of Fisheries Business Administration
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• v.31 no.2
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• pp.133-153
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• 2000

During the last several decades, Korea has been regarded as one of the fastest growing economies in the world. However, the small size of national land has not met the vigorous demand for land necessary to develop economic infra-structures such as large-scale harbors airports and highways. In order to satisfy the growing demand for land, the Korean government and industry have implemented the national land development programs to reclaim land from the sea fur the several decades. It is certain that these land development programs have resulted in a lot of property disputes between fishermen and public project administrators. This paper is to develop a quantitative model to estimate compensation for damages or restriction of charted fisheries resulting from large-scale public projects. In this paper, the compensation model is derived by using cost-volume-profit analysis framework because the compensation for charted fisheries basically depends on the factors such as the costs, production volume, profit of charted fisheries damaged or restricted by public projects. The model shows that the compensation for damages or restriction of charted fisheries is determined by the average annual profit, damage duration period, and the degree of fishery damages. In addition, the degree of fishery damages measured by the ratio of lost profit to annual average profit turns out to be determined by the following factors: annul profit, unit variable cost, decrease in production volume, the rate of increase in variable cost, and a change in fixed cost. Furthermore, this parer discusses the nam issues related to practices and regulation of the compensation for fishery damages in the current Fishery Act of Korea and suggests some appraisal methods which will be able to lead to theoretically correct and fair compensation for fisheries damages resulting from large-scale public projects.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.65-72
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• 2001

Since Pyoungtaek thermal power plant began using natural gas in 1986, the annual using volume has rapidly increased and reached 12.7 million tons in 1999. When the natural gas is cooled to a temperature of approximately -162$^{\circ}$C at atmospheric pressure, it condenses to a liquid called liquefied natural gas(LNG). LNG has a special characters such as odorless, colorless, non-corrosive, and non-toxic. So, LNG storage tank, tanker ship, transfer pipelines are required the special storage and transportation systems and technology. The presently operating LNG terminals are Pyongtaek and Inchon terminals. A total of 19 above-ground LNG storage tanks(100 thousand ㎘ grade) are currently in operation with a sendout capacity of 4,360tons/hour. To meet the growing domestic demand of LNG supply, the Inchon receiving terminal is expanding(six in-ground tank) and constructing a third LNG terminal at Tongyong. In this paper, case study on seepage analysis and countermeasure against increasing the seepage volume of in-ground LNG storage tank excavation work is reported. The results of an additional seepage analysis are presented to verify the design seepage volume of assumption section and seepage volume after curtain-grouting in the slurry wall.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.53
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• pp.315-336
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• 2012

In year 2011 export volume of South Korea surpassed 500billion USD and overall trade volume has exceeded one trillion USD. South Korea is ranked at 7th in the world by its export volume. Such an expansion of the trade volume leads to growth in customs clearance service demand. However, there are only handfuls of studies on the efficiency of customs clearance service which customs broker provide. If the efficiency in this study is not absolute, it shows relative efficiency to decision making unit. In this research survey was conducted targeting members of Korea Customs Brokers Association. Based on the survey improvement plans to enhance efficiency of customs clearances are as follows. First, rationalize the customs broker fee. Second, setup batch processing system to improve efficiency of the work process. Third, develop new area of task such as FTA and AEO certification. Forth, raise service quality by improving professionalism of customs brokers. Fifth, work efficiency of the office in the capital area will increase. Sixth, when inspecting import export cargo, customs broker should attend at the scene by their choice. Meanwhile, difference analysis on competent customs, type of office, and duration of the business was done but all the aspects were rejected. Such aspects does not influence on its effectiveness.

• KIEAE Journal
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• v.13 no.1
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• pp.57-63
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• 2013

Building Energy Efficiency Rating system was enforced in 2001 to enhance spreading high-energy performance and saving buildings. It was only for the new apartments, but expanded to new office buildings in 2010, and moreover, government offices require 1st grade of Building Energy Efficiency Rating system. Green Building Act, which is established to reduce the emissivity of carbon dioxide by reducing building energy consumption, will be enforced in 2013, and new apartments and office buildings will be subjected to it. Henceforward, it will extend to other types of buildings and will be phased in. In general, pumps and fans consume approximately half of the air-conditioning energy consumption, and about a quarter of the total building energy consumption when office buildings have total floor area of more than 10000 square meters. This study analyzed the energy demand when applying VAV(Variable Air Volume) and VWV(Variable Water Volume) System to reduce energy returns of the pumps and the fans by ECO2, which is a computer simulation program used for Building Energy Efficiency Rating system.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.1079-1090
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• 2021

This study examines the influence of individual investors' sentiment on Japanese IPO aftermarket performance (measured by return and trading volume on the first trading day and return on the first trading year). This study proposes that IPOs will be, on average overpriced on the listing day when individual investors' sentiment is highly optimistic. Higher initial return and trading volume are expected in IPOs with higher investors' optimism. Further, the positive initial return will occur in the short term as individual investors usually are uninformed investors who demand shares based on their personal preferences, which will last only in a short period. Following the overvaluation hypothesis, price reversals should be predicted once the effect of individual investors' optimism has disappeared, causing the IPOs to underperform in the long term. Using 520 Japanese IPOs issued from January 2010 to December 2019, this study reveals that individual investors' sentiment is positively and significantly related to returns and trading volume on the first trading day. Return reversals are found on the first trading year despite the insignificant influence of individual investors' sentiment on IPO return on the first trading year.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.9
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• pp.85-91
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• 2022

The demand for electric vehicles has increased because of environmental regulations. The lithium-ion battery, the most widely used type of battery in electric vehicles, is composed of a cathode, an anode, and an electrolyte. It is manufactured according to the pole plate, assembly, and formation processes. To improve battery performance and increase manufacturing efficiency, the manufacturing process must be optimized. To do so, simulation can be used to reduce wasted resources and time, and a finite-element method can be utilized. For high simulation quality, it is essential to reflect the material properties of the electrode by considering the pores. However, the material properties of electrodes are difficult to derive through measurement. In this study, the representative volume element method, which is a homogenization method, was applied to estimate the representative material properties of the electrode considering the pores. The representative volume element method assumes that the strain energy before and after the conversion into a representative volume is conserved. The method can be converted into one representative property, even when nonhomogeneous materials are mixed in a unit volume. In this study, the material properties of the electrode considering the pores were derived. The results should be helpful in optimizing the electrode manufacturing process and related element technologies.