공간연관성 지표를 이용한 낙동강 유역의 가뭄 핫스팟 지역 분석

손호준,변성호,박경운,김지은,김태웅 대한토목학회 2023 대한토목학회논문집 Vol.43 No.2

As drought risk increases due to climate change, various research works are underway around the world to respond to drought so as to minimize drought damage. In particular, in recent years, many studies are focused on analyzing regional patterns of drought in a comprehensive manner, however there is still insufficient to quantitatively identify drought-risk areas in a large river basin considering climate change in Korea. In this study, we calculated the Standardized Precipitation Index (SPI) and the Modified Standardized Precipitation Index (M_SPI) as representative meteorological drought index, and performed spatial autocorrelation analysis to identify the drought hotspot region under climate change scenarios of Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. The SPI was calculated by estimating parameters for each observation station within the study area, whereas the M_SPI was calculated by estimating parameters for the entire study area. It is more reasonable to use the M_SPI for assessing meteorological drought from an overall perspective within the study area. When the M_SPI was used, long-term droughts showed drought hotspot areas clearly larger than short-term droughts. In addition, the drought hotspot area moved from the center of the Nakdong River basin to the Seomjin River basin over time. Especially, the moving patterns of the short-term/long-term drought were apparent under the RCP 4.5, whereas the moving patterns of the long-term drought were distinct under the RCP 8.5 scenarios. 기후변화로 인해 가뭄의 위험도가 증가함에 따라, 전 세계적으로 가뭄의 피해 최소화를 위한 가뭄 대응 연구가 진행 중이다. 특히, 최근에는 가뭄의 지역적 패턴을 복합적으로 분석하기 위한 연구가 활발히 진행되고 있지만, 여전히 대하천 유역에서 가뭄 위험지역을 정량적으로 파악하는 연구는 부족한 실정이다. 본 연구에서는 표준강수지수(SPI)와 수정표준강수지수(M_SPI)를 산정하고, RCP4.5 및 RCP8.5 기후변화 시나리오에 대한 공간자기상관분석을 수행하여 가뭄 핫스팟 지역을 분석했다. SPI는 연구 지역 내의 분석단위별로 매개변수를 추정하여 지수를 산정하지만, M_SPI는 연구 지역 전체에 대한 매개변수를 추정하여 지수를 산정하기 때문에, 대상 지역 내의 전체적인 관점에서 기상학적 가뭄 판단에 더 합리적이다. 연구 결과, M_SPI를 사용했을 경우, 장기가뭄이 단기가뭄보다 명확히 큰 가뭄 핫스팟 지역을 나타냈다. 또한 가뭄 핫스팟 지역은 시간이 지남에 따라 낙동강 유역의 중심에서 섬진강 유역의 방향으로 이동하는데, RCP 4.5 시나리오는 단기/장기 가뭄의 이동패턴이, RCP 8.5 시나리오에서는 장기가뭄의 이동패턴이 뚜렷하였다.

삼나무, 편백의 연륜과 기후인자 분석을 통한 강원 동해안 지역 식재가능성 검토

손호준,김영설,김남영,이학봉,박완근 강원대학교 산림과학연구소 2014 Journal of Forest Science Vol.30 No.1

We measured radial growth of Cryptomeria japonica and Chamaecyparis obtusa growing in Gangneung, Boseong, Yangsan and Ulleung-do, respectively and analyzed its relationship with temperature and precipitation. We found from the result of tree ring counting that forest stands of Cryptomeria japonica in Gangneung and Boseong was 40 to 50 years old and 50 to 70 years old in Yangsan and Ulleung-do. According to climate change, the mean temperature in Gangneung was found to be 12℃ to 13℃ which was similar to that of Boseong and Yangsan 40 to 50 years ago. While the result of the radial growth measured from Cryptomeria japonica in Gangneung showed a slightly decreasing tendency compared to the other areas, Chamaecyparis obtusa showed an increasing tendency. In the case of Cryptomeria japonica, a strong negative correlation between radial growth and climate related variables including both mean temperature and mean precipitation existed in Ulleung. There was a strong negative correlation between radial growth and mean temperature for Chamaecyparis obtusa in Yangsan, although there was a positive correlation in Gangneung and Yangsan.

SWAP 지수를 활용한 한강유역의 가뭄-홍수 급변사상 특성 분석

손호준,이진영,유지영,김태웅 한국수자원학회 2021 한국수자원학회논문집 Vol.54 No.11

A drought-flood abrupt alternation event is an overlapping extreme event that is harder to cope with than a single event of drought and flood. It is also expected to have a significant adverse impact on ecosystems as well as industries and agriculture. However, there has not yet been a comprehensive study that characterizes the drought-flood abrupt alternation events in Korea. Therefore, this study employed a standard weighted average precipitation (SWAP) index, which is efficient to analyze not only individual events of drought and flood but also the drought-flood abrupt alternation events considering various time scales. The SWAP standardized the weighted average precipitation (WAP) by adding temporal weights to the precipitation. The SWAP indices were calculated for middle-sized watersheds of the Han River basin using the area average precipitation during 1966 and 2018. The severity K was calculated to represent the relative regional severity considering normal rainfalls, and used to characterize the drought-flood abrupt alternation in the study areas. The results indicated that 20 of the 30 middle-sized watersheds in the Han River basin were confirmed to increase the severity of drought-flood abrupt alternation over time. Considering the frequency and severity of drought-flood abrupt alternation events in each watershed, vulnerable areas and dangerous areas due to drought-flood abrupt alternation were identified, for example, the Upstream Namhan River (#1001). 가뭄-홍수 급변사상은 가뭄과 홍수가 중첩된 사상으로, 생태계뿐만 아니라 산업과 농업 그리고 사회경제까지 큰 영향을 미치기 때문에 가뭄이나 홍수의 개별 사상보다 대처하기 어렵다. 하지만 국내의 가뭄-홍수 급변사상에 대한 연구는 부족한 실정이다. 본 연구에서는 표준가중평균강수(SWAP) 지수를 사용하여 가뭄-홍수 급변사상의 특성들을 분석하였다. SWAP 지수는 일강수량에 시간 가중치를 적용한 가중평균강수(WAP) 지수를 표준화 것으로, 한강유역의 중권역별 면적평균강수량(1966-2018년)을 사용해 산정하였다. SWAP 지수는 가뭄·홍수의 단일사상 분석 뿐 아니라 가뭄-홍수 급변사상을 분석하는데 용이하고, 시간의 척도 측면에서도 유연하게 사용할 수 있다. 또한, 심각도 K를 사용해 가뭄-홍수 급변사상의 상대적인 심각도를 지역별로 분석할 수 있다. 연구 결과, 한강유역 30개의 중권역 중 20개의 중권역이 시간이 지남에 따라 가뭄-홍수 급변사상의 심각도가 상승하는 추세가 확인되었고, 중권역별 가뭄-홍수 급변사상의 발생 빈도와 심각도 등을 고려하여 위험지역을 확인할 수 있었다. 예를 들어, 한강유역 내 가뭄-홍수 급변사상으로 인한 위험지역은 남한강상류(#1001) 유역으로 나타났다.

산겨릅나무(Acer tegmentosum Maxim.) 자생지의 서식환경 특성 및 식생구조

손호준,김세창,이다현,권순재,박완근,김영설 경상대학교 농업생명과학연구원 2016 농업생명과학연구 Vol.50 No.3

The present study was to survey the site environment, vegetation structure and soil characteristics in the wild habitats of Acer tegmentosum Maxim. and offers basic information for habitats conservation and restoration. Most of the wild habitats were located at altitudes between 605~1,413m with inclinations ranged as 8~30°. The bare rock rate were 8~50%. The vegetation structure by the PC-ORD based on the Two Way Cluster Analysis were divided into three groups CommunityⅠ(Acer tegmentosum – Quercus mongolica), CommunityⅡ(Acer tegmentosum - Carpinus cordata), CommunityⅢ(Quercus mongolica – Tilia amurensis). The species diversity(H') was highest in CommunityⅡ as 1.474, CommunityⅠwas 1.471, Community Ⅲ was 1.219. The soil textures were Clay loam, The average soil pH was 4.8, Soil organic matter was 15.15% and available phosphorus was 2.33ppm. Ordination analysis result by soil characteristics, community, characteristic species showed that the greatest effect factors were slope, altitude, tree and shrub’s cover rate, organic matter, total-nitrogen, calcium, magnesium. Correlation analysis between environment factor result showed that O.M. - (T.N., K+, Mg2+, CEC, EC), T.N. - (K+, Mg2+, CEC, EC) were positive correlations.

얀센 메커니즘 로봇의 초음파 센서를 이용한 장애물 회피 알고리즘

손호준,신미경,이수홍 (사)한국CDE학회 2018 한국CAD/CAM학회학회지 Vol.24 No.2

본 논문은 기존의 얀센 메커니즘의 하드웨어 측면에 연구와 다르게 소프트웨어 측면에 더 초점을 두었다. M-sketch를 이용하여 구조적으로 얀센 메커니즘을 설계함과 동시에 초음파 센서를 통한 로봇의 장애물 회피알고리즘을 제시하였다. 본 적용된 알고리즘을 검증하기 위해서 V-rep 시뮬레이션을 진행하였으며 장애물 회피를 확인하였다.

강원도 지역 산림습원의 식물다양성 연구

손호준,김영설,김남영,이학봉,김세창,이희봉,박완근 한국자원식물학회 2015 한국자원식물학회지 Vol.28 No.4

This study was carried out to investigate the flora of indigenous habitat of Simjeok forest wetland, Mt. Jeombomg forest wetland, Mt. Sohwangbyung forest wetland, Jilmoi-neup, and Mt. Myeon forest wetland in Gangwon Province. The vascular plants were summarized as 547 taxa; 92 families, 296 genera, 468 species, 4 subspecies, 67 varieties, 8 forms. The plants that are specially noteworthy are 17 taxa of Korean endemic plants, 3 taxa of Critical Endangered Species (CR), 4 taxa of Endangered Species (EN), 8 taxa of Vulnerable Species (VU) and 17 taxa of Least Concemed Species (LC) in rare plants as categorized by the Korean Forest Service. Furthermore, V, IV, III degrees of floristic regional indicator plants as categorized by the Korean Ministry of Environment included 9 taxa, 14 taxa and 34 taxa, respectively. In addition, 25 taxa of naturalized plants were observed. In this study, we identified a variety of plants observed in the wetlands of Gangwon Province. We believe that this study will provide useful data for future research on the conservation and management of wetlands. 산림습원인 심적 산림습원, 점봉산 산림습원, 소황병산 산림습원, 질뫼늪 및 면산 산림습원을 대상으로 식물상 및 식물상의다양성을 분석하였으며, 그 결과는 다음과 같다. 조사지역에서확인된 관속식물은 92과 296속 468종 4아종 67변종 8품종 총547분류군으로 조사되었다. 조사 지역별로 살펴보면 심적 산림습원은 유역에서 269분류군이 습원 내에서 88분류군이 확인되었으며, 점봉산 산림습원은 유역에서 303분류군이 습원 내에서86분류군이 확인되었다. 소황병산 산림습원은 유역에서 303분류군이 습원 내에서 111분류군이 확인되었으며, 질뫼늪은 유역에서 209분류군이 습원 내에서 140분류군이 확인되었다. 면산산림습원은 유역에서 252분류군이 확인되었으며, 이중 습원 내에서 115분류군이 확인되었다. 이탄산림습원으로 알려진 용늪, 심적 산림습원, 점봉산 산림습원, 소황병산 산림습원, 질뫼늪및 면산 산림습원을 대상으로 식물상을 유집분석한 결과, 종조성은 습지의 형태 및 지리적 분포와 비교적 일치하는 경향을 보였다. 습원의 유역의 식물상 유사성을 보면, 점봉산 산림습원과면산 산림습원이 종유사성이 가깝게 나타났으며, 용늪과 질뫼늪도 종유사성이 비교적 가깝게 확인되었다. 습원 내의 식물상유사성은 심적 산림습원과 면산 산림습원이 가장 가깝게 나타났으며, 소황병산 산림습원과 질뫼늪도 종유사성이 높은 것으로 확인되었다. 절대습지식물(Obligate wetland plant, OBW) 의 유사성은 소황병산 산림습원과 질뫼늪이 가장 유사한 것으로 확인되었으며, 심적 산림습원과 면산 산림습원 또한 비교적유사한 것으로 나타났다.

VR HMD 기반의 스테레오스코픽 깊이 값 적용 연구

손호준,김정호,이승현,하마커 앨러릭,권순철 사단법인 인문사회과학기술융합학회 2016 예술인문사회융합멀티미디어논문지 Vol.6 No.4

Recently, technology of Virtual Reality(VR) based on HMD among various kinds of VR implemented products has received widespread attention. Major IT-related companies around the world participated in VR HMD research and development. Therefore, the possibility of the spread of VR HMD has been highly praised. Demands of VR HMD products using Smart Phone has been especially increased so that it is required to create a high quality of VR contents. The purpose of study in this paper is to apply the depth value of stereoscopic to VR HMD. To implement it, we analyzed VR HMD optical system and converted an experimental image to virtual depth caused by binocular disparity based on the result of calculating NPP(Native Pixel Parallax). We produced the image of stereoscopic applied with the value converted and applied to VR HMD. This study is expected to be utilized as a VR content creation field of quantitative data. 최근 다양한 가상현실 구현 장치 중 HMD(Head Mounted Display) 기반의 가상현실 구현 기술이 주목받고 있다. 전 세계의 주요 IT관련 회사들의 VR(Virtual Reality) HMD의 연구 개발의 참여로 VR HMD의 대중화 가능성을 높게 평가받고 있다. 특히, 높은 스마트폰 보급률에 따라 스마트폰을 활용하는 VR HMD 제품의 수요가 늘어나고 있으며, 이에 따라 스마트폰 환경에서의 고품질 가상현실 콘텐츠 제작이 요구되고 있다. 본 논문은 VR HMD에서의 스테레오스코픽 3D 깊이 값 적용에 연구 목적을 둔다. 이를 위해 VR HMD의 파라미터 값을 측정하고, 측정한 값을 바탕으로 광학 시스템을 분석하였다. NPP(Native Pixel Parallax) 계산을 바탕으로 좌/우 영상의 시차에 의해 가상 깊이로 환산하였다. 환산된 깊이 값을 적용한 스테레오스코픽 이미지를 제작하고, VR HMD에서 적용하였다. 본 논문은 가상현실 내의 깊이 값을 구현하는 고품질의 VR HMD 콘텐츠 제작 분야에 정량적 자료로 활용될 것으로 기대된다.

Monitoring and Evaluating the Severity of Drought-Flood Abrupt Alternation Events Using Daily Standardized Precipitation Index

손호준,김지은,변성호,이주헌,김태웅 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.2

A drought-flood abrupt alternation (DFAA) event is an extreme combination of an overlapping drought and flood resulting in adverse impacts on ecosystems and human society. As precipitation variability increases due to climate change, the occurrence and magnitude of DFAA events are expected to increase. Using daily precipitation data for 1966 − 2018, we calculated the daily standardized precipitation index for middle-sized watersheds and evaluated the severity of DFAA events in South Korea. The severity of DFAA events was evaluated in two ways: the severity of whole period (SWP) represents the total magnitude of DFAA event, and the severity of transition period (STP) indicates the instantaneous severity of DFAA event during the transition from drought to flood. The severities were also graded by the quantiles to identify risk regions, and we used precipitation concentration degree (PCD) and precipitation concentration period (PCP) to analyze the relationship between DFAA events and precipitation trends in South Korea. The results showed that the STP in the Yeongsan River basin and SWP in the Han River and the Nakdong River basin were higher than in the other basins. In addition, considering patterns and trends of the PCF and PCP in South Korea, this study found that the frequency and severity of DFAA events were high during flood seasons when precipitation was concentrated.

Implementation of dynamic visual acuity testing system using optical see through head mounted display

손호준,윤덕영,이승현,권순철 한국인터넷방송통신학회 2017 International Journal of Internet, Broadcasting an Vol.9 No.3

Dynamic visual acuity is used as an important factor to measure athletic performance in sports field. A study on visual acuity testing system using non-see head mounted display (NST-HMD) was conducted recently. However, the NST-HMD has a problem that the sense of space felt by the subject differs from the actual environment. This is because the view is blocked so that it is only implemented in a virtual space. This paper proposes a dynamic visual acuity testing system using optical see through head mounted display (OST-HMD). To do this, OST-HMD and NST-HMD comparative tests were conducted using existing K-D (King-Devick) charts. Experiments were performed on 30 subjects and their visual acuity was measured and analyzed by parametric statistics and one-sample T-test. The results of the study demonstrate the effectiveness of the proposed OST-HMD. This study is expected to use the visual inspection and training equipment of OST-HMD

한묵령 산림유전자원보호구역에 대한 식물상

손호준,김영설,Xinmei Jin,안치호,윤영균,박완근 한국산림휴양복지학회 2013 한국산림휴양학회 학술발표회 자료집 Vol.2013 No.4