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Comparison of Carbon Storage Based on Alternative Action by Land Use Planning (토지이용에 따른 대안별 탄소 저장량 비교)

  • Seulki Koo;Youngsoo Lee;Sangdon Lee
    • Journal of Environmental Impact Assessment
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    • v.32 no.6
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    • pp.377-388
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    • 2023
  • Carbon management is emerging as an important factor for global warming control, and land use change is considered one of the causes. To quantify the changes in carbon stocks due to development, this study attempted to calculate carbon storage by borrowing the formula of the InVEST Carbon Storage and Sequestration Model (InVEST Model). Before analyzing carbon stocks, a carbon pool was compiled based on previous studies in Korea. Then, we estimated the change in carbon stocks according to the development of Osong National Industrial Park (ONIP) and the application of alternatives. The analysis shows that 16,789.5 MgC will be emitted under Alternative 1 and 16,305.3 MgC under Alternative 2. These emissions account for 44.4% and 43.1% of the pre-project carbon stock, respectively, and shows that choosing Alternative 2 is advantageous for reducing carbon emissions. The difference is likely due to the difference in grassland area between Alternatives 1 and 2. Even if Alternative 2 is selected, efforts are needed to increase the carbon storage effect by managing the appropriate level of green cover in the grassland, creating multi-layered vegetation, and installing low-energy facilities. In addition, it is suggested to conserve wetlands that can be lost during the stream improvement process or to create artificial wetlands to increase carbon storage. The assessment of carbon storage using carbon pools by land cover can improve the objectivity of comparison and evaluation analysis results for land use plans in Environmental Impact Assessment and Strategic Environmental Impact Assessment. In addition, the carbon pool generated in this study is expected to be used as a basis for improving the accuracy of such analyses.

Characteristic Analysis of Tropospheric Ozone Sensitivity from the Satellite-Based HCHO/NO2 Ratio in South Korea (위성 기반 HCHO/NO2 비율을 통한 국내 대류권 오존 민감도 특성 분석)

  • Jinah Jang;Yun Gon Lee ;Jeong-Ah Yu;Kyoung-Hee Sung;Sang-Min Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.563-576
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    • 2023
  • In this study nitrogen dioxide (NO2), formaldehyde (HCHO) from the Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI), OMI/ Microwave Limb Sounder (MLS) tropospheric column ozone (TCO), and Airkorea ground-based O3 data were analyzed to examine the photochemical reaction relationship between tropospheric ozone and its precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs). As a result of analyzing the trend of long-term changes from 2006 to 2020 using OMI satellite data, TCO showed an increasing trend, NO2 steadily decreased, and HCHO continued to increase in Northeast Asia. In addition, formaldehyde nitrogen dioxide ratio (FNR; HCHO/NO2 ratio), an indicator of ozone sensitivity, is gradually increasing, which means that the VOC-limited regime is decreasing. This study conducted a sensitivity analysis of ozone generation using TROPOMI FNR and ground-based ozone (O3) over the recent years (2019~2022) to identify the possible cause for the continuous increase of ozone in Korea. Similar to the previous studies, VOC-limited and transitional regimes appeared in megacities, and VOC-limited regimes also appeared in areas where major power plants were located. In VOC-limited regimes, in other words, areas where NOx is excessively saturated, the reduction in NOx emissions may have weakened the ozone titration and thus led to the increase of ozone. Therefore, VOC emissions should be reduced in the short term rather than NOx emissions to reduce ozone concentrations under the VOC-limited regime.

Estimation of Chlorophyll Contents in Pear Tree Using Unmanned AerialVehicle-Based-Hyperspectral Imagery (무인기 기반 초분광영상을 이용한 배나무 엽록소 함량 추정)

  • Ye Seong Kang;Ki Su Park;Eun Li Kim;Jong Chan Jeong;Chan Seok Ryu;Jung Gun Cho
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.669-681
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    • 2023
  • Studies have tried to apply remote sensing technology, a non-destructive survey method, instead of the existing destructive survey, which requires relatively large labor input and a long time to estimate chlorophyll content, which is an important indicator for evaluating the growth of fruit trees. This study was conducted to non-destructively evaluate the chlorophyll content of pear tree leaves using unmanned aerial vehicle-based hyperspectral imagery for two years(2021, 2022). The reflectance of the single bands of the pear tree canopy extracted through image processing was band rationed to minimize unstable radiation effects depending on time changes. The estimation (calibration and validation) models were developed using machine learning algorithms of elastic-net, k-nearest neighbors(KNN), and support vector machine with band ratios as input variables. By comparing the performance of estimation models based on full band ratios, key band ratios that are advantageous for reducing computational costs and improving reproducibility were selected. As a result, for all machine learning models, when calibration of coefficient of determination (R2)≥0.67, root mean squared error (RMSE)≤1.22 ㎍/cm2, relative error (RE)≤17.9% and validation of R2≥0.56, RMSE≤1.41 ㎍/cm2, RE≤20.7% using full band ratios were compared, four key band ratios were selected. There was relatively no significant difference in validation performance between machine learning models. Therefore, the KNN model with the highest calibration performance was used as the standard, and its key band ratios were 710/714, 718/722, 754/758, and 758/762 nm. The performance of calibration showed R2=0.80, RMSE=0.94 ㎍/cm2, RE=13.9%, and validation showed R2=0.57, RMSE=1.40 ㎍/cm2, RE=20.5%. Although the performance results based on validation were not sufficient to estimate the chlorophyll content of pear tree leaves, it is meaningful that key band ratios were selected as a standard for future research. To improve estimation performance, it is necessary to continuously secure additional datasets and improve the estimation model by reproducing it in actual orchards. In future research, it is necessary to continuously secure additional datasets to improve estimation performance, verify the reliability of the selected key band ratios, and upgrade the estimation model to be reproducible in actual orchards.

Effects of Change in Patient Position on Radiation Dose to Surrounding Organs During Chest Lateral Radiography with Auto Exposure Control Mode (자동노출제어장치를 적용한 흉부 측면 방사선검사 시 환자 위치 변화가 주변 장기의 선량에 미치는 영향)

  • Seung-Uk Kim;Cheong-Hwan Lim;Young-Cheol Joo;Sin-Young Yu
    • Journal of the Korean Society of Radiology
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    • v.17 no.6
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    • pp.903-909
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    • 2023
  • The purpose of this study is to compare and analyze the effect of changes in the patient's central position on the exposure dose and image quality of surrounding organs during a chest lateral examination using an Auto Exposure Control(AEC). The experiment was conducted on a human body phantom. A needle was attached to the lower part of the center of the coronal plane of the phantom, and a lead ruler was attached to the lower part of the detector so that the 50 cm point was located at the lower center of the AEC ion chamber. The exposure conditions were 125 kVp, 320 mA, the distance between the source and the image receptor was 180 cm, and the exposure field size was 14 × 17 inches. Only one AEC ion chamber was used at the bottom center, and the density was set to '0' and sensitivity to 'Middle', and the central X-ray was incident vertically toward the 6th thoracic vertebra. With AEC mode applied, the 50 cm point of the needle and lead ruler were aligned and the phantom was moved 5 cm toward the stomach (F5) and 5 cm toward the back (B5), and the dose factor was analyzed by measuring ESD. The ESD of the thyroid gland according to the change in patient center position was 232.60±2.20 μGy for Center, 231.22±1.53 μGy for F5, and 184.37±1.19 μGy for B5, and the ESD of the breast was 288.54±3.03 μGy for Center, F5 was 260.97±1.93 μGy, B5 was 229.80±1.62 μGy, and the ESD of the center of the lung was 337.02±3.25 μGy for Center, F5 was 336.09±2.29 μGy, and B5 was 261.76±1.68 μGy. As a result of comparing the average values of dose factors between each group, the difference in average values was statistically significant (p<0.01), and each group appeared to be independent. As a result of the study, there was no significant difference in the dose to the thyroid, breast, and center of the lung according to the change in the patient's central position, except for the breast (10%) when the patient moved forward about 5 cm. However, movement of about 5 cm posteriorly resulted in an average dose reduction of 23.7%. Additionally, when the patient's central position was moved to the rear, image quality deteriorated.

Monitoring and Preventive Preservation of Cultural Heritages to Maintain Original Wooden Architectural Cultural Heritage (목조건축문화재 원형유지를 위한 문화재돌봄 모니터링과 예방보존)

  • CHUN Kyoungmee
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.192-214
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    • 2023
  • Wooden architectural cultural heritages are one of the visible legacies that show the national's identity. Even when the concept of 'the original' of cultural heritages was not accurately understood, the emphasis of preservation and management of cultural heritages was placed on 'preservation of the original form' or 'maintenance of the original form'. Moreover, these days, following the trend of international preservation principles, cultural heritages are considered important as "values as historical objects." This paper is the result of an attempt to determine the scope and content of what parts should be monitored to maintain the original form of wooden architectural cultural heritage. The first thing to be done in monitoring wooden architectural cultural heritage is to check the condition of the ground and foundation. The second is the column. This is because the instability of the column causes damage to the joint with each member and the fitting part, resulting in physical changes leading to damage to the wall. The third is monitor the roof tiles. If the leak continues into the building due to the separation or damage of the roof, the defect should be partially dismantled and repaired, so it should be monitored to maintain its original shape as much as possible. The monitoring range of the base, column, and roof serves as a reference point for identifying what damage is being done to the relevant cultural heritages. In other words, the data at the time when monitoring began becomes the 'original' for the year. Alternatives based on the analysis of monitoring for the preservation of original cultural heritages should be actively introduced. In addition, by sharing the current state and situation of cultural heritages as a result of monitoring with various related organizations, preventive preservation should be established rather than preservation of cultural heritages by "intervention."

Development of High-Resolution Fog Detection Algorithm for Daytime by Fusing GK2A/AMI and GK2B/GOCI-II Data (GK2A/AMI와 GK2B/GOCI-II 자료를 융합 활용한 주간 고해상도 안개 탐지 알고리즘 개발)

  • Ha-Yeong Yu;Myoung-Seok Suh
    • Korean Journal of Remote Sensing
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    • v.39 no.6_3
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    • pp.1779-1790
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    • 2023
  • Satellite-based fog detection algorithms are being developed to detect fog in real-time over a wide area, with a focus on the Korean Peninsula (KorPen). The GEO-KOMPSAT-2A/Advanced Meteorological Imager (GK2A/AMI, GK2A) satellite offers an excellent temporal resolution (10 min) and a spatial resolution (500 m), while GEO-KOMPSAT-2B/Geostationary Ocean Color Imager-II (GK2B/GOCI-II, GK2B) provides an excellent spatial resolution (250 m) but poor temporal resolution (1 h) with only visible channels. To enhance the fog detection level (10 min, 250 m), we developed a fused GK2AB fog detection algorithm (FDA) of GK2A and GK2B. The GK2AB FDA comprises three main steps. First, the Korea Meteorological Satellite Center's GK2A daytime fog detection algorithm is utilized to detect fog, considering various optical and physical characteristics. In the second step, GK2B data is extrapolated to 10-min intervals by matching GK2A pixels based on the closest time and location when GK2B observes the KorPen. For reflectance, GK2B normalized visible (NVIS) is corrected using GK2A NVIS of the same time, considering the difference in wavelength range and observation geometry. GK2B NVIS is extrapolated at 10-min intervals using the 10-min changes in GK2A NVIS. In the final step, the extrapolated GK2B NVIS, solar zenith angle, and outputs of GK2A FDA are utilized as input data for machine learning (decision tree) to develop the GK2AB FDA, which detects fog at a resolution of 250 m and a 10-min interval based on geographical locations. Six and four cases were used for the training and validation of GK2AB FDA, respectively. Quantitative verification of GK2AB FDA utilized ground observation data on visibility, wind speed, and relative humidity. Compared to GK2A FDA, GK2AB FDA exhibited a fourfold increase in spatial resolution, resulting in more detailed discrimination between fog and non-fog pixels. In general, irrespective of the validation method, the probability of detection (POD) and the Hanssen-Kuiper Skill score (KSS) are high or similar, indicating that it better detects previously undetected fog pixels. However, GK2AB FDA, compared to GK2A FDA, tends to over-detect fog with a higher false alarm ratio and bias.

GOCI-II Based Low Sea Surface Salinity and Hourly Variation by Typhoon Hinnamnor (GOCI-II 기반 저염분수 산출과 태풍 힌남노에 의한 시간별 염분 변화)

  • So-Hyun Kim;Dae-Won Kim;Young-Heon Jo
    • Korean Journal of Remote Sensing
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    • v.39 no.6_2
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    • pp.1605-1613
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    • 2023
  • The physical properties of the ocean interior are determined by temperature and salinity. To observe them, we rely on satellite observations for broad regions of oceans. However, the satellite for salinity measurement, Soil Moisture Active Passive (SMAP), has low temporal and spatial resolutions; thus, more is needed to resolve the fast-changing coastal environment. To overcome these limitations, the algorithm to use the Geostationary Ocean Color Imager-II (GOCI-II) of the Geo-Kompsat-2B (GK-2B) was developed as the inputs for a Multi-layer Perceptron Neural Network (MPNN). The result shows that coefficient of determination (R2), root mean square error (RMSE), and relative root mean square error (RRMSE) between GOCI-II based sea surface salinity (SSS) (GOCI-II SSS) and SMAP was 0.94, 0.58 psu, and 1.87%, respectively. Furthermore, the spatial variation of GOCI-II SSS was also very uniform, with over 0.8 of R2 and less than 1 psu of RMSE. In addition, GOCI-II SSS was also compared with SSS of Ieodo Ocean Research Station (I-ORS), suggesting that the result was slightly low, which was further analyzed for the following reasons. We further illustrated the valuable information of high spatial and temporal variation of GOCI-II SSS to analyze SSS variation by the 11th typhoon, Hinnamnor, in 2022. We used the mean and standard deviation (STD) of one day of GOCI-II SSS, revealing the high spatial and temporal changes. Thus, this study will shed light on the research for monitoring the highly changing marine environment.

Factors Influencing Acceptance and Use of New Technologies in the Metaverse Era : Focusing on the Difference between B2C Context and B2B Context (Metaverse 시대의 신기술 사용 의도에 영향을 미치는 요인: B2C 맥락과 B2B 맥락의 차이를 중심으로)

  • Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.4 no.3
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    • pp.125-139
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    • 2021
  • As the 4th industrial revolution progresses, new technologies and services are being born, growing, and maturing. Now, beyond the mobile era, the metaverse is being discussed as a new paradigm. Therefore, in this study, in preparation for the metaverse era, we tried to analyze what factors have an important influence when consumers want to use new technologies. In particular, the research was conducted focusing on how the context in which consumers use the technology changes depending on whether they are B2C or B2B. For this, augmented reality (AR) was selected in the B2C context by linking the research subject with the metaverse era, and the smart factory was selected in the B2B context. The research model for the analysis was established by deriving and setting common influence variables by reflecting the characteristics of the research target technology based on the modified extended unified theory of acceptance and use of technology. A survey was conducted for empirical analysis, and 150 AR and 150 smart factory subjects were analyzed. The empirical study results are as follows. The relationship between performance expectancy and intention to use, technology readiness and intention to use was found to have a significant positive (+) effect on both AR and smart factory. On the other hand, it was found that effort expectancy, social influence, and trust had a positive (+) effect on intention to use only in AR. Only in smart factory, facilitating conditions had a significant positive (+) effect on intention to use. It was also found that the perceived risk had a significant negative (-) effect on the intention to use only in the smart factory. The results of this study are academically significant in that we empirically test that influencing factors of technology use varies depending on the context in which it is used by consumers. In practice, it provided an implication of what to focus on first is being implemented.

A Study on Changes in Consumption Behavior due to the Risk of the COVID-19 Pandemic (COVID-19 팬데믹 위험으로 인한 소비행동의 변화 연구)

  • Oh, Jong-chul;Lee, Yu-sun;Kim, Jae-hong
    • Journal of Venture Innovation
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    • v.5 no.2
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    • pp.49-66
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    • 2022
  • This study intends to examine how the perception of covid-19 risk affects consumers' consumption behavior based on previous studies in a situation where the spread of covid-19 is prolonged. This study demonstrates how consumers' perception of covid-19 risk affects online and offline consumption behavior through the perceived severity, perceived vulnerability, coping effectiveness, and self-efficacy of the revised protective motivation theory (Rogers, 1983). We want to test it through analysis. In order to achieve the purpose of this study, consumers living in Seoul and Gyeonggi Province who have purchased within the past 3 months were selected as a sample. In addition, variable data such as risk perception of covid-19, perceived severity, perceived vulnerability, coping effectiveness, self-efficacy, online purchase attitude and purchase intention, offline purchase attitude and purchase intention were collected through the questionnaire.A total of 363 copies of valid responses were tested to test the hypothesis of the relationship between variables through the covariance structure model. The analysis results of this study were first, that covid-19 risk perception had a significant positive (+) effect on perceived severity, perceived vulnerability, and coping effectiveness. Second, perceived severity and perceived vulnerability were found to have a significant positive (+) effect on offline purchasing attitude. Third, perceived severity, perceived vulnerability, coping plan effectiveness, and self-efficacy were all found to have significant positive (+) effects on online purchase attitude. Finally, it was found that offline purchase attitude and online purchase attitude had a significant positive (+) effect on offline purchase intention and online purchase intention, respectively. Also, it was found that online purchase attitude had a negative (-) effect on offline purchase intention. The results of this analysis will provide meaningful implications for the establishment of strategies for distribution channels according to the social risk of infectious diseases.

An Empirical Study on the Effects of Personal Characteristics and Drama Characteristics on Entrepreneurial Intention : Focusing on the Moderating Effect of Social Support (개인 특성과 드라마 특성이 창업의지에 미치는 영향에 관한 실증 연구 : 사회적 지지의 조절효과 중심으로)

  • Chang, Soo-jin
    • Journal of Venture Innovation
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    • v.5 no.4
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    • pp.135-156
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    • 2022
  • This study attempted to identify the factors affecting entrepreneurial intention and to confirm the moderating effect of social support that plays a positive role in increasing entrepreneurial intention. The subjects of the study were 419 ordinary people, and data were obtained online and analyzed. The analysis method of this study was based on the SPSS statistical program Ver. 24, and a hierarchical regression analysis method was conducted to analyze the moderating effect. The results of hypothesis verification analysis in this study are as follows. First, innovativeness, risk-taking, self-fulfillment, economic motivation, immersion in a drama, drama role model, and indirect experience, all had a significant positive(+) effect on entrepreneurial intention. Second, among the factors affecting entrepreneurial intention, self-fulfillment was found to have the greatest influence. Third, it was confirmed that the moderating effect of social support between various variables and entrepreneurial intention had a significant effect on innovativeness, self-fulfillment, drama role model, and indirect experience, and entrepreneurial intention. The academic value of this study is to confirm the effect of drama characteristic variables on entrepreneurial intention. In addition, it was possible to confirm the moderating effect of social support, which is the total of individual external support. The implication of this study is that the desire for achievement had the greatest influence on entrepreneurial intention. Therefore, it is necessary to develop a desire to achieve in start-up support policies and start-up education. In addition, in light of the ripple effect of TV dramas, drama role model and indirect experience increase entrepreneurial intention, so it was possible to predict its influence on changes in perception of start-ups and entrepreneurs.