• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.64.1-64.1
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• 2017

접촉쌍성 EK Com은 0.2667일의 짧은 주기를 가진 만기형 식쌍성으로 광도곡선의 변화로 인해 연구자마다 이계의 하위 유형을 다르게 언급하여 하위유형의 혼동이 있는 천체이다. 우리는 소백산천문대에서 2009년 5월 VR 필터로, 2013년 2 ~ 5월 사이 BVRI 필터로, 2016년 1 ~ 4월 사이 R 필터로 CCD 측광 관측하여 3개의 새로운 광도곡선을 획득하였다. 우리의 관측 자료와 SuperWASP의 공개된 자료로부터 40개의 새로운 극심시각을 산출하였다. 이 극심시각을 포함하여 155개의 극심시각을 여러 문헌에서 수집하여 주기 연구를 수행한 결과, EK Com의 공전주기는 영년 주기 증가와 더불어 8.2년의 주기적인 변화가 겹쳐 변화함을 발견하였다. 이러한 주기 변화 원인에 대하여 살펴본 결과, 영년주기변화는 질량이 작은 별에서 큰 별로의 질량이동에 의하여 일어나고, 주기적인 변화는 질량이 큰 주성의 자기 활동에 의해 발생할 수 있음을 보였다. Wilson-Devinney code를 이용한 광도곡선 분석을 통하여 EK Com은 개기식이 부식에 있는 하위 유형 A라기 보다 주식에 있는 W형에 속하며, 모든 광도곡선에서 1개의 Hot spot과 1개의 Cool spot을 가진 모형이 가장 관측치를 잘 설명한다. W UMa형 별들의 HR도, 온도비, 질량의 그래프에서 EK Com은 W형 Group들이 있는 위치에 존재한다. 이는 광도곡선에서 유추한 EK Com의 하위 유형과도 일치한다.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.241-259
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• 2006

Polydnavirus is a mutualistic DNA virus found in some braconid and ichneumonid wasps. Its genome is integrated into host chromosome as a provirus. Its replication occurs at ovarian calyx epithelium during host pupal stage to form episomal viral particles. The viral particles are delivered into hemocoel of the parasitized insect along with eggs during wasp oviposition. Several polydnaviral genomes, which are isolated from the episomal virus particles, have been sequenced and exhibit some gene families with speculative physiological functions. This review presents the viral characteristics in terms of Its parasitic physiology. For developing new insect pest control tactics, it also discusses several application strategies exploiting the viral genome to manipulate insect physiology.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.1 s.31
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• pp.71-80
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• 2005

Recently, water quality problems are emerging as important social issues since water quality in rivers and lakes are significantly deteriorated. Thus, an accurate prediction system on reservoir water quality is required, as well as an integrated system which can provide a solution for taking away contaminated materials. This research aims to develop an intelligent decision support system, which uses a GIS enabling management and spatial analysis. The developed system is a prototype that can be applied into real spot. This research area includes the following main subjects; system analysis and design, geometry data collection and database implementation, data acquisition and analysis on reservoir water quality, interface design and development GIS, and development of an expert system for water quality forecasting by WASPS.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.6
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• pp.124-136
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• 2002

A freshwater lake water quality management system(FLAQUM) was developed to help regional manager for the water quality of a rural basin. The integrated user interface system FLAQUM written in Visual Basic, includes three subsystems such as a database management system, basin pollutant loads simulation model using SWMM model and freshwater lake water quality simulation model using WASP5 model. Pollutant load simulation model was applied to simulate the discharge and pollutant loading from the watershed, and freshwater lake water quality model was applied to analyze the changes in water quality with respect to watershed pollutant loads, and this model could be used in planning to control watershed pollutant source for water quality management. Database management system was constructed fur all input and output data processing, and it can be used to analyze statistical characteristics using constructed data. Results are displayed both graph and text for convenience of user. The results of FLAQUM application to Boryeong freshwater lake showed that the lake was in eutrophic condition. The major contribution of pollution comes from tributary No.1 and No.4, which have a large number of livestock farms. Therefore, water quality management must be focused on appropriate management of the livestock farming in the two breanchs.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.142.2-142.2
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• 2012

Hoffmeister(1943)에 의해 변광성으로 발견된 V345 Cas (2MASS J23083986+5406545, ${\alpha}$(2000.0)=23h08m39.86s & ${\delta}(2000.0)=+54^{\circ}06^{\prime}54.6^{\prime\prime}$)는 B 필터에서 13.1~14.2의 광도 변화를 보이는 것으로 알려진 별이다. 우리는 레몬산 천문대(LOAO)에서 2007년과 2008년에 걸쳐 총 22일간 V345 Cas의 BVRI CCD 측광관측을 수행하여, 처음으로 V345 Cas의 년도 별 전체 광도곡선을 완성하였다. 우리의 관측 자료와 Super WASP에서 공개한 자료를 이용하여 각각 7개의 극심시각을 산출하였다. 우리가 결정한 극심시각을 포함하여 여러 문헌에서 수집한 총 68개의 극심시각을 이용하여 V345 Cas의 주기 분석을 수행하였다. 그 결과, V345 Cas의 궤도주기는 포물선 모양의 영년변화와 함께 약 30년의 규칙적인 변화를 겪고 있음을 발견하였다. 규칙적인 변화를 제3천체에 의한 광시간 효과로 가정하여 관측된 극심시각에 잘 맞는 광시간 궤도 해를 산출한 결과, 영년주기가 증가하는 경우와 감소하는 경우에 대해, 각각 29.0년과 39.7년 주기를 갖는 두 개의 광시간 궤도 해가 가능하다. 이러한 모호성을 해결하기 위해서 앞으로의 극심시각 관측이 중요하다. 2007년과 2008년 BVRI 광도곡선들은 부극심을 기준으로 좌우가 거의 대칭이며, 1년 사이에 특기할 만한 광도변화를 보이지 않았다. 우리는 이 광도곡선들을 Wilson-Devinney 쌍성 모델을 이용하여 분석하여, V345 Cas의 측광학적 해를 처음으로 산출하였다. 우리가 구한 해에 의하면, 약 88도의 궤도경사각에 두 성분별의 질량비가 약 0.5인 V345 Cas는 질량과 표면 온도가 큰 주성과 로쉬 로브를 채우고 있는 반성으로 구성된 준 분리형 식쌍성계이다.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.3
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• pp.128-132
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• 2006

Interstate electric power system, as an alternative for energy cooperation under regional economic bloc, has been hotly debated before progressing the restructure in electric power industry and rapidly expanded in many regions after 1990s. Especially, since northeast asia has strong supplementation in resource, load shape, fuel mix etc., electric power system interconnection in this region may bring considerable economic benefits. Moreover, since Korean electric power system has a great difficulty in a geographical condition to interrupt electricity transaction with other countries, it has been expanded as an independent system to supply all demand domestically. As a result, Korean electric power system makes considerable payment for maintaining system security and reliability and expands costly facilities to supply a temporary summer peak demand. Under this inefficiency, if there are electricity transactions with Russia via the North Korea route then economic electric power system operation nay be achieved using seasonal and hourly differences in electricity price and/or load pattern among these countries. In this paper, we estimate price cap of transacted electricity via interstate electric power system in northeast asia. For this study, we perform quantitative economic analysis on various system interconnection scenarios.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.793-796
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• 1996

This study proposes a new algorithm which performs a production simulation under various constraints and maintains computational efficiency. In order to consider the environmental and operational constraints, the proposed algorithm is based on optimization techniques formulated in LP form In the algorithm, "system characteristic constraints" reflect the system characteristics such as LDC shape, unit loading order and forced outage rate. By using the concept of Energy Invariance Property and two operational rules i.e. Compliance Rule for Emission Constraint, Compliance Rule for Limited Energy of Individual Unit, the number of system characteristic constraints is appreciably reduced. As a solution method of the optimization problem, the author uses Karmarkar's method which performs effectively in solving large scale LP problem. The efficiency of production simulation is meaningful when it is effectively used in power system planning. With the proposed production simulation algorithm, an optimal expansion planning model which can cope with operational constraints, environmental restriction, and various uncertainties is developed. This expansion planning model is applied to the long range planning schemes by WASP, and determines an optimal expansion scheme which considers the effect of supply interruption, load forecasting errors, multistates of unit operation, plural limited energy plants etc.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.878-882
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• 1996

This paper discusses the definition and concepts, approach methodologies, capable application areas in electricity business, and tentative calculation of avoided generation costs based on the Korea's official long-term generation expansion plan. The objective to evaluate avoided costs of a resource is to supply decision makers with the breakeven cost of a targeting avoided resource. For the evaluation of avoided costs of the Korea's generation system, we consider the pseudo-DSM option which has 1,000MW peak savings, load factor with 70 percent, and life-time With 25 years as the avoided resource. The DSM resource can save the fuel and capacity additions of a electric utility during its life time. The capacity and fuel savings are evaluated from the two different cashflows with and Without the DSM option, which are generated on the basis of the generation system optimization model(WASP-II), independently. The breakeven kWh costs of the DSM option over this 25-year period is projected to be 34.1[won/kWh], which is composed of generation-capacity and fuel avoided costs with 101.139[won/kW] and 17.6[won/kWh], respectively.

• Korean Journal of Environmental Agriculture
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• v.38 no.2
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• pp.104-109
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• 2019

BACKGROUND: The invasive hornet Vespa velutina nigrithorax has becomes a public concern in rural and urban South Korea. The technologies are necessary to develop a way to counter V. velutina. In an effort to develop a way to counter V. velutina, we found that a bacillus strain, named Bacillus sp. BV-1, produces volatile compounds that attract V. velutina. METHODS AND RESULTS: Field trials of V. velutina attraction were performed using plates and traps containing BV-1 cultures grown on sugar medium. When the sugar medium and sugar-grown BV-1 cultures in the plates were placed close together, V. velutina visited preferably the plates with the BV-1 cultures. Significantly more V. velutina were caught in the traps containing BV-1 cultures than in those containing only sugar medium. Headspace solid-phase microextraction coupled with GC/MS analysis of BV-1 cultures detected 2-methyl-1-propanol, 3-methyl-1-butanol, 3-methylbutanoic acid, ethyl hexanoate, 2-pheylethanol, ethyl octanoate, and ethyl decanoate as the major volatiles. CONCLUSION: BV-1 cultures were suggested as potential agents for managing V. velutina as they produce volatile compounds that attract the hornet.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.365-369
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• 2023

The genus Bitomus Szepligeti, 1910 (Hymenoptera: Braconidae: Opiinae) is known to parasitize in mining flies (Diptera: Agromyzidae), of which four species are recorded in Korea. Bitomus was revised by Fischer (1987, 1994) and recently treated by Papp (1978, 1981) in Korea. Bitomus is distinguished from other genera by the immovably joined second-third or fourth metasomal tergites, forming a carapace. In this study, Bitomus indicus is recognized for the first time in Korea. This study provides a diagnosis, description, distribution, and diagnostic illustrations.