• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.73-79
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• 2004

Mountain side ditch is constructed at the top of cutting slopes around road and it drains the surface water that flowed from upper part. Mountain side ditch is constructed to keep away the influx of the surface water into cutting faces. However, if Mountain side ditch is constructed on the top of cutting slopes, it is cause of trouble. For example, difficulty of quality control and lack of drainage faculty. Therefore, the faculty and establishment propriety of mountain side ditch are evaluated seriously, according to the condition of ground, topography and rainfall in this paper. Results from the study for the numerical analysis of effect of mountain side ditch indicate that safety factor is enlarged about 3% at rainfall.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.475-488
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• 2018

This study evaluates geothermal system efficiency in terms of input power and heat exchange volume on the heat-source and load sides, by applying a combined open-closed type loop system comprising a geothermal system and a groundwater well to a cultivation site. In addition, this study analyzes the effects of heating and cooling for a complex geothermal system, by evaluating the temperatures of an external site and a cultivation site during operation. During cooling operations the heat exchange volume on the heat source side, average 90.0kW/h for an open type system with an input of 235L/minute groundwater, and 40.1kW/h for a closed type system with an input of 85L/minute circulating water, for a total average heat exchange volume of 130.1kW/h. The actual heat exchange volume delivered on the load side averages 110.4kW/h. The average EER by analysis of the geothermal system's cooling efficiency is 5.63. During heating operation analysis, the heat exchange volume on the heat source side, average 60.4kW/h in an open type system with an input of 266L/minute groundwater, and 22.4kW/h in closed type system with an input of 86L/minute circulating water, for a total average heat exchange volume of 82.9kW/h. The actual heat exchange volume delivered on the load side averages 112.0kW/h in our analysis. The average COP determined by analysis of the geothermal system's heating efficiency is 3.92. Aa a result of the tradeoff between the outside temperature and the inside temperature of the production facility and comparing the facility design with a combined well and open-closed loops geothermal(CWG) system, we determine that the 30RT-volume CWG system temperature are lower by $3.4^{\circ}C$, $6.8^{\circ}C$, $10.1^{\circ}C$ and $13.4^{\circ}C$ for ouside temperature is of $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$ and $35^{\circ}C$, respectively. Based on these results, a summer cooling effect of about $10^{\circ}C$ is expected relative to a facility without a CWG system as the outside temperature is generally ${\geq}30^{\circ}C$. Our results suggest that a complex geothermal system provides improvement under a variety of conditions even when heating conditions in winter are considered. Thus It is expected that the heating-cooling tradeoffs of complex geothermal system are improved by using water screen.

• 대한핵의학회:학술대회논문집
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• 1977.05a
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• pp.95.3-96
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• 1977

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.187-187
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• 2012

최근 환경에 대한 관심이 증대하면서 생물다양성, 홍수조절, 온실가스 저감 등 다양한 기능을 수행하는 습지에 대한 보전 및 복원을 위한 많은 노력들이 진행되고 있다. 습지 보전 및 복원을 위한 다양한 방안 중 하나가 댐 및 주변지역을 습지로 조성하여 활용하는 방안이라고 할 수 있으며, 이를 위해서는 댐 및 주변지역의 습지로서의 활용을 위한 특성 파악이 우선적으로 이루어져야 한다. 따라서 본 연구에서는 댐 주변지역에 조성된 습지와 댐 저수지 자체를 모두 포함하여 댐습지라고 정의하고, 댐습지가 지니고 있는 습지의 기능 및 경제적 가치를 추정하고자 하였다. 본 연구의 대상지역은 기준습지와 대상습지로 구분되며, 기준습지는 우포늪과 보령댐, 대상습지는 용담댐이다. 댐습지의 기능평가는 수문지형학적 특성을 고려하는 HGM(Hydrogeomorphic Method)을 이용하였으며, 가치평가는 조건부가치측정법(CVM)을 이용하였다. 기능평가 결과는 우포늪과 보령댐을 각각 기준지역으로 선정하였을 경우로 구분하여 나타낼 수 있다. 자연습지인 우포늪을 기준지역으로 선정하였을 경우에는 댐의 주목적과 관련이 있는 수문학적 기능이 높게 평가되었으나 습지 내에서 진행되는 생지화학적 기능과 다양한 식물 종에 대한 서식처로써의 기능은 다소 미흡한 것으로 평가되었다. 보령댐을 기준지역을 선정하였을 경우에는 일부 기능을 제외하고 대부분의 기능이 유사한 것으로 평가되었다. 조건부가치측정법을 이용한 용담댐의 경제적 가치평가는 댐습지 생태공원조성에 따른 훼손된 습지의 보호, 희귀생물종의 보호, 휴양 및 여가기능 제공을 주요인으로 설정하고 설문조사를 수행하여 가치를 추정하였다. 그 결과 용담댐의 총 가치는 우포늪의 가치와 비교하였을 때 우포늪의 35~41%에 해당하는 것으로 추정되었다. 본 연구에서 수행된 댐습지의 기능 및 가치평가 결과는 댐이 단순히 이 치수 측면으로만 이용되는 것이 아니라 생태학적으로도 활용성이 있다는 사실을 나타내고 있다. 이를 통해서 향후 댐의 친환경적 활용 방안 및 댐습지 관리 방안에 중요한 기초자료로 활용될 수 있을 것으로 판단되며, 댐에 대한 긍정적인 인식 증진에도 많은 도움이 될 것으로 판단된다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.301-302
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• 2001

본 연구에서는 공단에서 발생하는 악취물질을 냄새센서를 이용하여 상시 감시하는 것을 목적으로 한다. 현재 다종다양한 냄새를 측정하기 위한 악취평가 방법으로는 관능측정법이 이용되고 있다. 그러나 이 방법은 악취판정원의 냄새세기의 차이와 판정원(panel)의 생체리듬에 따른 차이로 인하여 냄새의 객관적인 평가에 무리가 따르며, 언제, 어디서 돌발적으로 발생하는 악취의 연속적인 감시에 문제점을 나타내고 있다. 더욱이 우리나라는 환경 악취에 대해 직접관능측정법에 의한 악취 측정이 실시 되고 있어서 객관적으로 악취평가를 하기가 매우 곤란하다. (중략)

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.295-301
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• 2020

Radiation exposure exposed during mammography, which is performed for early examination of breast cancer, has also been suggested as a cause of carcinogenesis in the past, and scattered rays generated during examination may cause unnecessary radiation exposure to surrounding organs. In this study, the Monte Carlo simulation was used to evaluate the human organ doses exposed during conventional mammography, and to estimate the dose reduction effect for each organ when using 3D printing materials for radiation protection by scattered rays. As a result of organ dose evaluation, the breast on the opposite side of the examination was about 22.0% of the breast on the test side and about 58.6% on the eye, which was highly influenced by the scattering-ray. When using the 3D printing shield to protect it, the breast on the opposite side of the test showed an effective dose reduction effect at a thickness of 1 mm.

• Journal of Korea Port Economic Association
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• v.39 no.1
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• pp.35-46
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• 2023

This study was conducted to evaluating the willingness to pay for marine leisure ships through a contingent valuation method that can estimate the value of non-market economy. The questionnaire adopted a double-bound dichotomous choice Model and the variables for evaluating the amount of willingness to pay consisted of demographic variables and respondent behavior variables, and related information verified through previous studies. As a result of collecting and analyzing a total of 309 questionnaires, the amount of willingness to pay for marine leisure ships was estimated to be 25,510 won. In addition, significant variables affecting the amount of willingness to pay were the experience of visiting the island, satisfaction with the introduction of new maritime transportation, and intention to revisit the island. Through this study, it can be used as a basis for evaluating the economic value of new maritime transportation by estimating the willingness to pay for marine leisure ships using the contingent valuation method.

• Journal of the Korean Society of Radiology
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• v.10 no.4
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• pp.271-278
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• 2016

This study was fulfilled to evaluate the absorbed dose of breast and adjacent organs using MIRD type phantom in brachytherapy of breast cancer. The absorbed dose was analyzed assuming left or right breast is source organ which is $^{103}Pd$ or $^{192}Ir$. As a result, $^{192}Ir$ dose is higher than $^{103}Pd$ in source organ and also in contralateral breast. Particularly, significant adjacent organs are lung, liver, heart and contralateral breast in brachytherapy of breast cancer.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1D
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• pp.61-70
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• 2010

In case of low benefit project with low traffic or high-priced project, existing analysis of cost and benefit tends to present a low feasibility. However, considering the improvement of environment, intensification of disaster prevention, public stability of countryside area and formation of good scenery, these projects can have a feasibility. This paper analyzes and summarizes the indirect benefit of some ripple effects, caused by road projects, and presents the methodology and process in order to change the indirect benefit into monetary value.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.7-12
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• 2013

Environmental measurements in the many different types of horticultural farms were carried out to evaluate the ventilation performance for multi-span plastic greenhouses according to the eaves height, the number of spans, the existence of side wall vents and the position of roof vents. Hydroponic tomatoes were being cultivated in all experimental greenhouses, and ventilation rates of the greenhouses were analyzed by the heat balance method. It showed that the ventilation rate in the greenhouse with 4 m eaves height increased about 22% compared to the greenhouse with 2 m eaves height. The ventilation rate in the greenhouse with 9 spans decreased about 17% compared to the greenhouse with 5 spans. In the greenhouse with 9 spans, if there were no side wall vents, the ventilation rate showed about a third of the case that side wall vents were open. Overall, as the eaves height was higher and the number of spans was smaller in multi-span greenhouses, the natural ventilation performance was better. And the ventilation performance was best in the greenhouse which the eaves height was high and the position of roof vents was ridge, not gutter. Therefore, in order to maximize the natural ventilation performance, multi-span plastic greenhouses need to improve their structures such as that make the eaves height higher, place the roof vents on the ridge, install the side wall vents as much as possible, and the number of spans is limited to about 10 spans.