퇴적암반과 결정질암반에서의 심층처분장 부지조사를 위한 반사법탐사 사례 연구

권형석,한만호,공남영,문윤섭,오석훈 한국자원공학회 2023 한국자원공학회지 Vol.60 No.5

Crystalline and sedimentary rocks are the preferred host rocks in deep repositories for spent nuclear fuels. This study examined the Swiss case of sedimentary rocks and Swedish and Canadian cases of crystalline rocks. In Switzerland, a reflection survey was used to identify the candidate host rock for the disposal site as the Opalinus clay formation and to create images of the boundaries of the Mesozoic sedimentary layers, including the Opalinus clay formation. A 3D reflection survey was conducted to determine the distribution and small-scale faulting of the Opalinus clay formation. Sweden conducted reflection surveys at the Forsmark site to obtain geological information on the deformation lenses within the site and to characterize the geology of the three deformation zones near the site. Canada conducted a reflection survey at the Ignace site to obtain information on its geological structure, including the location and dipping angles of the reflectors distributed in the vicinity of the site.

분산형 전원을 포함하는 배전계통을 위한 조류계산 기법 연구

권형석,Kwon, Hyung-Seok 한국조명전기설비학회 2005 조명·전기설비학회논문지 Vol.19 No.2

This paper addressed the issue of the three-phase load flow program for electric power distribution systems that include distributed generations. The equipment models were selected in order to consider imbalances among phases for the load flow analysis of distribution systems. Also, power equations and measurement functions are newly derived. The load flow analysis program developed in this paper was tested for the propriety of algorithm and convergence characteristics by case studies on test systems in various scales and types. 본 논문에서는 분산형 전원을 포함하는 배전계통을 위한 3상 조류계산 프로그램에 대하여 소개한다. 배전계통의 조류계산을 위하여 각 상간에 존재하는 불평형을 모두 고려할 수 있도록 계통 내 설비들의 모델을 선정하였으며, 전력방정식이나 측정함수 등도 새로 유도하였다. 본 논문을 통해 개발된 조류계산 프로그램은 다양한 크기와 형태의 시험계통에 대해 사례연구를 시행함으로써 알고리즘의 타당성 및 프로그램의 수렴성을 검증하였다.

Analysis of Semantic Network in Life Science Domains on Middle School Textbook Based on 2009 Revised National Science Curriculum by Publisher

권형석,김영신 한국교원대학교 뇌기반교육연구소 2018 Brain, Digital, & Learning Vol.8 No.1

The textbook is the most fundamental and objective tool used by teachers and students in schools for the purpose of learning. The textbook writer is required to organize the content so that it can be logically understood by selecting the main concepts of the educational process. Studies so far have displayed restrictions in emphasizing the relationship and importance between concepts by merely providing the frequency and repetition of different concepts in a quantitative manner. Thus, this study has analyzed the life science unit of middle school science textbooks used in the 2009 revised educational curriculum in terms of the conceptual network by publishers. The middle school science textbooks published by three publishing companies were analyzed. The conclusion of this study is as set forth below. 1) There is a difference in terms of the number of concepts and network structure between publishers and units. 2) Second, the structure of the network of concepts was complex. 3) Third, the central concept of each unit varied based on the publisher. Based on this study, it is expected that the number of concepts in each unit of the new textbook will be reduced to form a simplified conceptual structure and a network that is connected to their related concepts. Furthermore, it is anticipated that this study will be helpful in the selection of textbooks that suit the characteristics of the students by adjusting the number of concepts proposed by each unit, irrespective of the author writing the unit.

Random Forest 기법을 이용한 도심지 MT 시계열 자료의 차량 잡음 분류

권형석,류경호,심익현,이춘기,오석훈 한국지구물리.물리탐사학회 2020 지구물리와 물리탐사 Vol.23 No.4

We performed a magnetotelluric (MT) survey to delineate the geological structures below the depth of 20 km in the Gyeongju area where an earthquake with a magnitude of 5.8 occurred in September 2016. The measured MT data were severely distorted by electrical noise caused by subways, power lines, factories, houses, and farmlands, and by vehicle noise from passing trains and large trucks. Using machine-learning methods, we classified the MT time series data obtained near the railway and highway into two groups according to the inclusion of traffic noise. We applied three schemes, stochastic gradient descent, support vector machine, and random forest, to the time series data for the highspeed train noise. We formulated three datasets, Hx, Hy, and Hx & Hy, for the time series data of the large truck noise and applied the random forest method to each dataset. To evaluate the effect of removing the traffic noise, we compared the time series data, amplitude spectra, and apparent resistivity curves before and after removing the traffic noise from the time series data. We also examined the frequency range affected by traffic noise and whether artifact noise occurred during the traffic noise removal process as a result of the residual difference. 2 01 6년 9월에 발생한 경주지진원 구역에 대한 정밀 지질구조 규명을 위해 MT 탐사를 적용하였다. 경주지역의MT 측정자료는 조사지역 인근의 지하철, 전력선, 공장, 주택, 농경지에서 발생된 전기적 잡음과 철도, 도로에서의 차량잡음 등으로 인해 측정자료 왜곡이 심하게 발생되었다. 이 연구에서는 고속철도 및 고속도로와 인접한 4개소의 MT 탐사자료에 기계학습 기법을 적용하여 차량잡음이 포함된 시계열을 분류하였다. 고속열차 잡음이 포함된 시계열에 대해서는확률적 경사 하강법, 서포트 벡터 머신과 랜덤 포레스트 3가지의 분류모델을 적용하여 그 결과를 비교하였다. 대형트럭잡음이 포함된 시계열 자료에 대해서는 Hx 성분, Hy 성분과 Hx & Hy 합성성분 크기에 대한 3가지의 샘플 자료를 준비하였으며 랜덤 포레스트 분류모델을 구성하여 그 성능을 평가하였다. 마지막으로 차량잡음 제거 효과 분석을 위하여 차량잡음 제거 전후의 시계열, 진폭 스펙트럼과 겉보기비저항 곡선을 비교하였으며, 이를 통해 차량잡음이 영향을 미치는주파수 대역과 차량잡음 제거 시 발생될 수 있는 문제점에 대해 고찰하였다.

돌망태석축의 실험적 연구

권형석,정철호,백영식 대한토목학회 1993 대한토목학회 학술발표회 논문집 Vol.1993 No.1

2009 개정 중학교 과학 교과서 광합성 단원의 개념 네트워크 분석

권형석,박인경,김영신 한국생물교육학회 2018 생물교육 Vol.46 No.1

The textbook is the most fundamental and objective tool used by teachers and students in schools for the purpose of learning. The science is particularly a subject that displays a clear ranking relationship, so the content in a textbook must be suitable for the level of study. Thus, the textbook writer is required to organize the content so that it can be logically understood by selecting the main concepts of the educational process. However, studies so far have displayed restrictions in emphasizing the relationship and importance between concepts by merely providing the frequency and repetition of different concepts in a quantitative manner. Thus, this study has analyzed a network of the photosynthesis unit in science textbooks for middle schools currently used in the 2009 revised curriculum. The units of photosynthesis were divided and analyzed in three sub-unit of photosynthesis, transfer of water and nutrition, and the composition of plants. The NetDraw program was used to analyze the network of concepts. The conclusion of this study is as follows. First, there are many scientific concepts in science textbooks, which result in a complex structure. There are many similarities between the science textbook concept network and the top 30% concept network, so it will be necessary to reduce the number of concepts in science textbooks. Second, the level of achievement criteria in curriculum was sufficiently reflected in the textbook. Third, the three sub-unit of photosynthesis are connected by the concepts regarding cells, root, stem, and leaves. Through this study, it is anticipated that the concepts in the photosynthesis unit in textbooks will be connected in a more meaningful manner, and further studies will be conducted to analyze the degree of consistency of textbooks, in addition to the concepts used in actual schools.

계측에 의한 비탈의 변형거동 분석

정철호,최진국,권형석,김효진 대한토목학회 1994 대한토목학회 학술발표회 논문집 Vol.1994 No.1

GPR탐사를 이용한 댐체 기초암반 파쇄대 영상화

권형석(Kwon Hyoung Seok),최준호(Choi Joon Ho),노병돈(Ro Byung Don),김용표(Kim Yong Pyo),오병화(Oh Byung Hwa) 대한토목학회 2009 대한토목학회 학술대회 Vol.2009 No.10

복합배전계통에서 계통손실을 고려한 분산형 전원의 위치선정 및 상태추정

권형석(Kwon Hyung-Seok),김홍래(Kim Hongrae) 한국산학기술학회 2004 한국산학기술학회논문지 Vol.5 No.6

전력 소비자 근처에 설치, 운영하는 소규모 발전 형태인 분산형 전원에 대한 관심이 최근 들어 커지고 있다. 전력산업 구조개편이 진행되고 있는 현 상황에서 분산형 전원을 배전계통 내에 설치하고, 배전계통의 상태추정 기법을 적용하여 배전계통 운영을 안정적이고 신뢰성 높게 하려는 시도가 이루어지고 있다. 본 논문에서는 배전계통에 분산형 전원을 추가하였을 때 계통 손실에 미치는 영향을 분석하여 분산형 전원의 최적위치를 선정하고, 분산형 전원이 포함된 배전계통을 위한 상태추정 기법을 개발하였다. 불량데이터에 대한 강건성이 뛰어난 WLAV 상태추정기를 구현하였으며, 단일, 다중, 상호작용 불량 데이터에 대한 테스트를 실시하였다. IEEE 34 모선 수지상 계통을 사용하여 사례연구를 수행함으로써 제안한 알고리즘의 타당성을 확인하였다. Recently, It IS Increasing the concern of distributed generations(DGs) that installed small power at a site near by the customer. In deregulation environment, not only distributed generation operation but also state estimation is the key function in distribution systems. This paper process to calculate the impact of distributed generation on a distribution feeder. WLAV state estimation is performed the distribution systems with DGs and bad data test including single, multiple, interacting. Simulations with test cases are performed and the results are presented, using IEEE 34 bus radial distribution systems.

전자유도 탐사를 이용한 지하매설물 탐지 정확도 분석

권형석(Hyoung Seok Kwon),최준호(Joon ho Choi),황대진(Dae jin Hwang),김문재(Mun jae Kim),윤정섭(Jeoung seob Yoon) 한국방재안전학회 2008 한국방재안전학회 논문집 Vol.1 No.4

전자유도 탐사는 매설관로에서 발생되는 자기장을 측정하는 탐사방법으로 하나의 관로만 매설되어 있는 경우에는 20cm 이내의 높은 정확도를 보이지만, 탐지대상 관로 인근에 다른 관로가 매설되어 있으면 자기장의 교란으로 정확도가 감소한다. 본 연구에서는 지하매설물 탐지 정확도 향상을 위하여 대칭성을 이용하여 매설관로의 수평위치를 검증하는 방법과 에너지 크기 비교법과 삼각법을 이용하여 매설심도를 검증하는 방법에 대해 고찰하였다. 다음으로 현재 판매되는 전자유도 탐사장비가 별도의 저장장치를 가지고 있지 않아 측정자료의 분석이 불가능한 문제를 개선하기 위하여, Bluetooth 무선통신장치를 이용하여 측정자료를 저장하는 방법을 개발하였다. 마지막으로 두개의 인접관로를 하나로 오인하는 문제점을 개선하기 위하여 현장모형실험을 통해 인접관로의 거리에 따른 분해능을 고찰하였다. Electromagnetic induction surveys are one of the useful methods to detect the location and buried depth of underground utilities by measuring horizontal and vertical magnetic fields. It can effectively detects single buried utility with the accuracy of within 20 cm. However when another utility is buried near to target one, the accuracy of utility location considerably decreases due to the distortion of magnetic fields caused from adjacent utility. This study shows the ways to verify the location and buried depth of target utility when magnetic fields does not show symmetric distribution due to adjacent another utility. Using Bluetooth wireless communication tools, we developed the way to records measured magnetic fields to handheld PDA. We investigated the criteria for minimum distance of two adjacent utilities to separate the individual responses through field model test