• 환경영향평가
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• 제20권5호
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• pp.729-745
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• 2011

The purpose of this paper is to estimate the external diseconomies of an unwelcomed facility on the nearby houses. The facility and the area studied are Dangin-Ri power plant in Mapo-Gu, Seoul and the residential district surrounding it respectively. The nearby housing prices have been changed according to the time and circumstances of the public announcements about the reconstruction or removal plans of the plant. These price changes are regarded as the capitalized values of the external diseconomies due to the plant. This study is based on the hedonic price theory in order to estimate the diseconomies in monetary value. The tools for the estimation are four models of multiple regression with the transaction price as the dependant variable and various housing characteristics including the external effects of the plant as the independent variables. The sample analyzed is 833 house transactions for the past 5 years in the research area. The facts found are as follows; First, the most suitable functional form for the estimation is confirmed to be the linear model. Second, there are significant differences in influence on the housing values among the independent variables, that is, locational characteristics, physical features, and environmental changes with time. Third, the external diseconomy is estimated as \80,137,807 in case that the plant would be reconstructed in the underground of the present site, whereon a substitutional public park would be constructed and as \59,142,248 in case that the plant would move away.

• Journal of Magnetics
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• 제18권4호
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• pp.481-486
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• 2013

An electromagnetic launcher (EML) system accelerates and launches a projectile by converting electric energy into kinetic energy. There are two types of EML systems under development: the rail gun and the coil gun. A railgun comprises a pair of parallel conducting rails, along which a sliding armature is accelerated by the electromagnetic effects of a current that flows down one rail, into the armature and then back along the other rail, but the high mechanical friction between the projectile and the rail can damage the projectile. A coil gun launches the projectile by the attractive magnetic force of the electromagnetic coil. A higher projectile muzzle velocity needs multiple stages of electromagnetic coils, which makes the coil gun EML system longer. As a result, the installation cost of a coil gun EML system is very high due to the large installation site needed for the EML. We present a coil gun EML system that has a new structure and arrangement for multiple electromagnetic coils to reduce the length of the system. A mathematical model of the proposed coil gun EML system is developed in order to calculate the magnetic field and forces, and to simulate the muzzle velocity of a projectile by driving and switching the electric current into multiple stages of electromagnetic coils. Using the proposed design, the length of the coil gun EML system is shortened by 31% compared with a conventional coil gun system while satisfying a target projectile muzzle velocity of over 100 m/s.

• 한국지반환경공학회 논문집
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• 제13권8호
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• pp.25-33
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• 2012

터널 설계 시 해당지반에 관한 정보를 정확히 반영하는 것은 대단히 중요하다. 하지만 다양한 지형 및 지질조건을 모두 고려한 지반조사 및 시험 등은 경제적, 기술적으로 인하여 현실적으로 실시하기 어렵기 때문에 한정된 정보에 의하여 해석 및 설계를 하고 있는 실정이다. 본 연구는 도심지 및 산악지역 터널공사 시, 보다 정확한 안정성 검토 및 거동 예측을 수행하여 선정 결과에 대한 현장 적용성 여부를 판단하기 위해 인공신경망 이론의 적용을 통하여 기존 거동예측의 한계성을 극복하고자 하였다. 먼저, 현장 데이터를 확보하여 인공신경망 중 다층퍼셉트론을 연구에 적합한 구조로 구축하고, 역전파 알고리즘으로 학습시켜 적용하였다. 인공신경망을 이용한 현장적용성의 학습을 위한 자료는 터널의 지보패턴, RMR, Q, 암종, 굴진장, 굴착형태, 굴착경과일 등 터널거동에 영향을 미치는 영향인자를 고려하여 신뢰성 분석을 실시하고 선별된 계측자료의 결과를 데이터베이스화하여 사용하였다. 학습이 완료된 인공신경망 모델을 이용하여 터널시공현장의 굴착경과일에 따른 천단변위, 내공변위, 지중변위, 록볼트축력을 예측하고 현장 계측치와 비교분석을 통하여 인공신경망을 이용한 터널 시공 시 현장적용성을 확인하였다.

• Genomics & Informatics
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• 제4권1호
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• pp.33-39
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• 2006

Alternative splicing (AS) is an important mechanism of producing transcriptome diversity and microarray techniques are being used increasingly to monitor the splice variants. There exist three types of microarrays interrogating AS events-junction, exon, and tiling arrays. Junction probes have the advantage of monitoring the splice site directly. Johnson et al., performed a genome-wide survey of human alternative pre-mRNA splicing with exon junction microarrays (Science 302:2141-2144, 2003), which monitored splicing at every known exon-exon junctions for more than 10,000 multi-exon human genes in 52 tissues and cell lines. Here, we describe an algorithm to deduce the relative concentration of isoforms from the junction array data. Non-negative Matrix Factorization (NMF) is applied to obtain the transcript structure inferred from the expression data. Then we choose the transcript models consistent with the ECgene model of alternative splicing which is based on mRNA and EST alignment. The probe-transcript matrix is constructed using the NMF-consistent ECgene transcripts, and the isoform abundance is deduced from the non-negative least squares (NNLS) fitting of experimental data. Our method can be easily extended to other types of microarrays with exon or junction probes.

• Ocean Systems Engineering
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• 제4권4호
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• pp.263-278
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• 2014

The spudcan requires the suitable design considering the soil, platform, and environmental conditions. Its shape needs to be designed to secure sufficient reaction of soil so that it can prevent overturning accidents. Its shape also has to minimize the installation and extraction time. Even in the same soil condition, the reaction of soil may be different depending on the shape of spud can, mainly the slope of top and bottom plates. Therefore, in this study, the relation between the slope of plates and the reaction of soil with and without water jetting is analyzed to better understand their interactions and correlations. For the investigation, a wind turbine installation jack-up rig (WTIJ) is selected as the target platform and the Gulf of Mexico is considered as the target site. A multi layered (sand overlying two clays) soil profile is applied as the assumed soil condition and the soil-structure interaction (SSI) analysis is performed by using ANSYS to analyze the effect of the slope change of the bottom plate and water jetting on the reaction of soil. This kind of investigation and simulation is needed to develop optimal and smart spudcan with water-jetting control in the future.

• 대한기계학회논문집A
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• 제29권2호
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• pp.284-292
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• 2005

Material flaws in the from of pre-existing defects can severely affect the crack initiation. Stress distribution and crack initiation life of engineering materials such as monolithic aluminum alloy and Al/Glass fiber laminate may be different according to the defect location. The aim of this study is to evaluate effects of relative location of defects around the circular hole in monolithic aluminum and Al/Glass fiber laminates under cyclic bending moment. Stress distribution and crack initiation behavior near a circular hole are considered. Results of Finite Element (FE) model indicated the features of different stress field due to the relative defects positions. Especially, the defects positions at ${\theta}=0^{\circ}\;and\;{\theta}=30^{\circ}$ was strongly effective in stress concentration factor ($K_t$) and crack initiation behavior.

• 한국물환경학회지
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• 제24권2호
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• pp.156-163
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• 2008

This study was to introduce a methodology of ecological health assessment for efficient management and to provide some diagnostic results of the survey. We evaluated ecological health assessment at five sampling locations of Sikjang Mountainous Stream using the index of biological integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) during May - October 2006. The health condition, based on the IBI model, averaged 32 and varied from 27 to 37 depending on the sampling sites. Thus, the stream health was judged as "good" to "fair" conditions. IBI values showed slight differences between upstream and downstream sites. Whereas, QHEI values varied from 75 (fair condition) to 196 (excellent condition) and QHEI at St. 4~5, indicating the downstream reach had significantly lower than the headwater site (St.1). Regression analyses also showed that QHEI values had a linear decrease from the headwater to downstream. This result indicated that habitat quality was rapidly degradated by human influence. Overall, data of IBI and QHEI suggested that the stream health was maintained well in the present but the habitat and biological quality were partially degradated in the downstream. So, the human interference should be minimized to protect the downstream environment.

• 조명전기설비학회논문지
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• 제19권6호
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• pp.22-28
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• 2005

접지설계에 있어서 토양의 전기적 특성은 접지극의 형상과 더불어 가장 중요한 설계요소 중 하나이며 이러한 토양의 전기적 특성은 접지극이 매설될 지역의 고유한 저항률, 즉 고유저항률(specific earth resistivity)로 대표되어 왔다. 이처럼 고유저항률에 근거한 수작업 접지설계는 복잡한 구조와 특성을 갖는 실제 토양을 균일한 매질로 등가 화하는 절차를 필요로 한다. 본 논문에서는 미얀마 500[kV] 송전철탑 수작업 접지설계를 위하여 수평다층토양을 균일 매질로 등가화 하는 절차를 제시하였다.

• Asian Journal of Atmospheric Environment
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• 제4권2호
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• pp.72-79
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• 2010

In this study, the ionic composition of volcanogenically derived particles and their temporal and spatial distributions have been investigated to evaluate the impact of the volcanic eruption on the local ecosystem and residents. To this end, an intensive field study was conducted to measure the size-segregated particulate matters at the east part of Sakurajima in Japan. Fractionated sampling of particles into > $PM_{10}$, $PM_{10-2.5}$, and $PM_{2.5}$ was made by a multi nozzle cascade impactor (MCI). The concentration of various ions present in the size-resolved particles was determined by Ion chromatography. The time dependent 3-dimensional Volcanic Ash Forecast Transport And Dispersion (VAFTAD) model developed by the NOAA Air Resources Laboratory (ARL) indicated that the sampling site of this work was affected by the volcanic aerosol particles plume. The temporal distributions of sulfate and $PM_{2.5}$ during the field campaign were significantly variable with important contributions to particle mass concentration. The chlorine loss, suspected to be caused by acidic components of volcanic gases, occurred predominantly in fine particles smaller than $10\;{\mu}m$.

• 정보처리학회논문지D
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• 제11D권5호
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• pp.1143-1148
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• 2004

분산 애플리케이션을 위한 다계층 모델 또는 분산 아키텍처를 개발하기 위해서는 웹디자이너와 페이지 작성가의 역할 분리, 엔터티 정의와 사용에 대한 고려, 데이터베이스 연결 및 관리, 트랜잭션 처리 둥 여러 가지 사항을 고려하여야 한다. 본 논문에서는 분산 애플리케이션 개발시 여러 고려사항에 대한 해결책으로 웹 계층 오브젝트 모델링 방법을 사용하는 DONSL(Data Server of Non SQL-Query) 아키텍처를 제안한다. 이 아키텍처는 트랜잭션 처리를 지원하고 웹 계층과 DBMS 사이에는 질의 로직을 단순화하는 방법을 통해 성능을 보장하는 구조이다. 제안한 개념적인 프레임웍은 각 계층(tier)의 작업을 단순화시키고 엔터티와 DAO(Data Access Object)를 제거시킴으로서 중대규모 사이트 구현을 용이하게 하는 방법을 제공한다.