• Spatial Information Research
• /
• 제8권1호
• /
• pp.171-182
• /
• 2000

분류기법에 의해 원격탐사 영상으로부터 취득된 면속성 수치 지도는 GIS 의사결정자료로 사용되기 이전에 그 정확성에 관한 신뢰도 검증과정을 거쳐야 한다. 분류 정확도를 평가하기 위해서는 오분류행렬(confusion matrix)을 사용하여 전체 정확도, 사용자 정확도, 제작자 정확도 등을 얻게 되는데, 이때 오분류행렬을 구성하기 위해서는 기준자료(reference data)에 대한 표본추출이 이루어져야한다. 기준자료의 표본을 추출하는 기법간의 비교 및 표본 크기를 줄이고자 하는 연구는 많이 이루어져 왔으나, 추출된 표본들간의 거리를 줄임으로서 정확도 평가 비용을 감소시키고자 하는 연구는 미비한 실정이다. 따라서 본 연구에서는 프랙탈 분석을 통하여 기준자료의 표본을 추출하였으며, 이를 바탕으로 기존의 표본추출의 기법과 정확도 차이 및 비용효과 측면을 비교 분석하였다. 연구 결과 , 프랙탈 분석을 통하여 표본을 추출하는 기법은 그 정확도 추정에 있어 기존의 표본추출 기법과 큰 차이를 보이지 않았으며, 추출된 화소들이 가까운 저리에 군집에 있어 비용효과측면에서 유리함을 확인하였다.

• 보존과학회지
• /
• 제35권4호
• /
• pp.331-343
• /
• 2019

The purpose of this study was to investigate the material characteristics of black wares excavated from Yongyeon-ri, Damyang and to clarify the correlation of the factors that develop black coulor compared with black wares excavated from other regions. As a results of absorption rate, colour coordinate, compositional mineral, section analysis and contents showed high correlation between the kilns and the waste dumplings, indicating that they were made using the same materials. Second, comparing the microtextures and contents of the glaze layer with the excavated sherds from other kilns, a characteristic coagulation phenomena of iron oxides were not observed in Yongyeon-ri and Gilmyeong-ri, and it was considered that the material, mixing ratio, and firing environment were different from those of Bonggok-dong. In addition, statistical analysis using the major components revealed that the bodies of Yongyeon-ri were highly correlated with those of Bonggok-dong, which is nearest to the region, and similar to Gilmyeong-ri in the glaze layer. The characteristics of colorant were different depending on Fe₂O₃ content and K₂O content also contributed to the classification of the composition of each excavated kiln. Conclusionally, it can be seen from the scientific analysis that the colour of black wares excluded from different regions is materially different from that of iron oxide, the coloring condition, and the firing environment.

• 천문학회보
• /
• 제37권1호
• /
• pp.86.2-86.2
• /
• 2012

We present the study of association between sub-photospheric flow and photospheric magnetic fields of active regions respectively derived from the local helioseismology and observed magnetic fields. It is believed that the energetic transients, e.g., flares and CMES, are caused by changes in magnetic and velocity field topologies in solar atmosphere. These changes are essentially brought about by the magnetic fields that are rooted beneath the photosphere where they interact and get affected by sub-photospheric flows. Therefore, we expect the topology of sub-surface flows to be correlated with the observable topology of magnetic fields at the photosphere and higher layers. In order to examine the correlation, if any, we computed the near photospheric flows and photospheric magnetic fields using the Doppler velocity and magnetic fields observations, respectively, provided by the SDO/HMI. The high resolution Doppler observations from the HMI enabled us to compute the very high p-modes parameters which sample the sub-photosphere shallow near the photosphere. Furthermore, we compute the sub-photospheric flow topology parameters, e.g., vorticity, kinetic helicity, and photospheric magnetic field topology parameters, e.g., magnetic helicity, from the magnetic fields observations to compare their associations. We present the result of the analysis in the paper.

• 무역학회지
• /
• 제47권4호
• /
• pp.271-292
• /
• 2022

In Korea, the road transport industry is pointed out as a major cause of air pollutants, so management control is needed. Existing studies used only positive input and output variables to measure regional efficiency. However, it is necessary to consider the environmental pollution problem in efficiency analysis. In this study, an undesirable SBM analysis using CO₂ was conducted to measure efficiency of domestic regions. In addition, SDM was conducted to examine the ripple effect between domestic regions. As a result of the analysis, the efficiency of the capital area such as Seoul, Gyeonggi, and Incheon was high in the road transport industry. However, the efficiency of the road transportation industry in Daegu and Gangwon was low. In the SDM analysis, it was found that the regional equipment capabilities had a great influence on efficiency. In order to improve efficiency, it is necessary to increase and improve the equipment capacity of the road transport industry.

• Ocean and Polar Research
• /
• 제45권2호
• /
• pp.89-102
• /
• 2023

Climate and environmental changes in the Arctic Ocean due to global warming have been linked to extreme climate change in mid-latitude regions, including the Korean Peninsula, requiring a better understanding of the Arctic climate system based on the paleo-analog. This review introduces three paleoenvironmental research cases using neodymium isotopes (¹⁴³Nd/¹⁴⁴Nd, ε_Nd) measured on two different fractions of marine sediments: silicate-bound 'detrital' and Fe-Mn oxide-dominated 'authigenic' fractions. In the first case, detrital ε_Nd in core HH17-1085-GC on the continental shelf off northern Svalbard was used for tracing changes in sediment provenance and associated glacier behavior over the last 16.3 ka. The second case showed the potential use of authigenic ε_Nd as a quasi-conservative water mass tracer. Three prominent ε_Nd peaks and troughs observed in core PS72/410-1 from the Mendeleev Ridge in the western Arctic Ocean over the past 76 ka suggested episodic meltwater discharge events during 51~46, 39~35 and 21~13 ka BP. The last case proposed the use of the difference between authigenic and detrital ε_Nd as a proxy for reconstructing glacier fluctuation. The idea is based on the assumption that enhanced glacial erosion during glacier advances can supply sufficient freshly-exposed rock substrate for incongruent weathering, potentially leading to greater isotopic decoupling between bedrock and dissolved weathering products as recorded in detrital and authigenic ε_Nd, respectively. Thus, it would be worthwhile to take advantage of sedimentary ε_Nd to improve our understanding of past environmental changes in polar regions.

• KIEAE Journal
• /
• 제11권4호
• /
• pp.19-27
• /
• 2011

This study aims to find the determining factors for apartment rental prices by using Stepwise Multiple Regression Analysis. In the process, differences among the groups and multicollinearity and correlation between the variables are examined using analysis of variance(ANOVA), correlation analysis and factor analysis. The comprehensive analysis of reliability of the variable and comprehensivization ensure objectivity. For this analysis, the characteristics of the determining factors for apartment rental prices by sub-regions in Seoul are as follows : First, the housing supply rate appears center of the central and the southwest region is influenced by the cultural and ecological environment, convenience, the size of the complex and reputation of the developer. Second, the northeast region is generally influenced by the regional economy, housing size, the density of the complex, well-known construction companies and relevant variables of individual housing and the density of the complex, physical and social environment, reputation of the developer, local economy and housing size. Lastly, the southeast region appears to be influenced by the local economy, the density of the complex, housing size and the educational environment.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(C)
• /
• pp.447-451
• /
• 2010

In this paper, we propose a simple but effective algorithm to increase the speed of Emphysema region classification. Emphysema region classification method based on CT image consumes a lot of time because of the large number of subregions due to the large size of CT image. Some of the sub-regions contain no Emphysema and the classification of these regions is worthless. To speed up the classification process, we create an algorithm to select Emphysema region candidates and only use these candidates in the Emphysema region classification instead of all of the sub-regions. First, the lung region is detected. Then we threshold the lung region and only select the dark pixels because Emphysema only appeared in the dark area of the CT image. Then the thresholded pixels are clustered into a region that called the Emphysema pre-detected region or Emphysema region candidate. This region is then divided into sub-region for the Emphysema region classification. The experimental result shows that Emphysema region classification using predetected Emphysema region decreases the size of lung region which will result in about 84.51% of time reduction in Emphysema region classification.

• 한국환경복원기술학회지
• /
• 제24권2호
• /
• pp.57-69
• /
• 2021

Urban green spaces supply ecosystem services (ESs), which are consumed by city residents and generate demand, to improve air quality. It is important to determine supply and demand for ESs and reduce the gap for efficient management. This study proposed a method to use the concept of supply and demand for ESs in the decision-making process for urban planning or management. PM₁₀ concentrations were converted to weight for demand assessment on PM₁₀ reduction, and PM₁₀ absorption capacity of all green spaces including the forests, and that of urban green spaces excluding forests, was calculated for each supply assessment. The differences in the calculated supply and demand were analyzed to derive the mismatched regions in Suwon. As a result, regions with big forested areas showed sufficient supply, indicating that the degree of mismatch among administrative neighborhoods (dong) varied greatly depending on whether they had a forest. An analysis of only urban green spaces showed that all neighborhoods lacked supply. Forests with high PM₁₀ absorption capacity had a great effect, but urban green spaces can be considered a key element in reducing PM₁₀ in daily life. Considering the mismatch of supply and demand, spatial distribution, and population distribution, it is possible to prioritize the supply of urban green spaces to reduce PM₁₀ and, furthermore, support decision making for priority zones subject to forest conservation and designation and cancellation of green spaces, which gives significance to this study.

• 대기
• /
• 제34권3호
• /
• pp.233-255
• /
• 2024

This study analyzed the distribution of Aerosol Robotic Network (AERONET) Version 3 Level 2.0 data, spanning over two decades, across South Korea and its six administrative regions (Seoul metropolitan area, Chungcheong, Jeolla, Gangwon, Gyeongsang, and Jeju). The research assessed long-term trends in aerosol optical depth (AOD) and mass concentration of particulate matter (i.e., PM₁₀ and PM_2.5), using data from the AERONET direct sun product and AirKorea, respectively. Additionally, eight aerosol types were identified using the scattering Ångström exponent and absorption Ångström exponent from the AERONET inversion product. The study further explored their domestic and regional distributions. Findings indicated that AERONET data were predominantly concentrated in the western regions of South Korea, including the Seoul metropolitan area, Chungcheong, and Jeolla, with a higher frequency of data in spring, thus demonstrating spatial and temporal heterogeneity. The annual average AOD exhibited a declining trend of -0.006 yr^-1. Similarly, PM₁₀ and PM_2.5 mass concentrations decreased by -1.324 ㎍ m^-3 yr^-1 and -1.335 ㎍ m^-3 yr^-1, respectively. These trends in AOD and PM₁₀ (PM_2.5) demonstrated positive correlations, with correlation coefficients of 0.674 (0.753) and statistically significant low p-values of 0.00058 (0.03), respectively. The analysis also revealed that aerosols in South Korea predominantly consisted of black carbon (BC) or BC-mixed types (84.09%), with a notable presence of smaller, less absorbent aerosol types (13.11%).

• 환경정책연구
• /
• 제9권4호
• /
• pp.53-76
• /
• 2010

본 논문은 제주와 강원을 제외한 전국을 5개의 광역 경제권으로 구분하여, 권역별로 이산화탄소 배출량에 대한 환경 쿠즈네츠 곡선을 추정 비교하고 그 정책적 시사점을 도출하고자 하였다. 이를 위해 1990 - 2007년에 걸쳐 5개 광역경제권의 이산화탄소 배출량에 대한 패널자료를 구축하였다. 슈어(Seemingly Unrelated Regression, SUR)모형을 통해 권역 간 밀접한 상호의존성을 고려하였으며, 에너지원의 가격지수와 인구밀도 등을 추가적인 설명변수로 고려하였다. 그 결과 5권역 모두에서 이산화탄소 배출에 대한 환경 쿠즈네츠 곡선의 존재를 상당히 일관되게 확인할 수 있었으나, 그 소득 전환점들은 1,370만 원에서 2,115만 원 사이에 놓여 있는 것으로 계산되어 권역별 차이가 어느 정도 존재하는 것으로 나타났다. 이러한 권역별 차이는 이산화탄소 배출량 감축과 관련된 정책의 더욱 효과적인 추진을 위해 적절히 고려될 필요가 있다. 아울러 에너지원의 가격 상승은 대체로 일인당 이산화탄소의 배출량을 줄이는 데 기여하였으며, 반면에 인구밀도의 증가는 대체로 일인당 이산화탄소 배출량을 증가시키는 것으로 나타나고 있다.