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Estimation of TROPOMI-derived Ground-level SO2 Concentrations Using Machine Learning Over East Asia (기계학습을 활용한 동아시아 지역의 TROPOMI 기반 SO2 지상농도 추정)

  • Choi, Hyunyoung;Kang, Yoojin;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.275-290
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    • 2021
  • Sulfur dioxide (SO2) in the atmosphere is mainly generated from anthropogenic emission sources. It forms ultra-fine particulate matter through chemical reaction and has harmful effect on both the environment and human health. In particular, ground-level SO2 concentrations are closely related to human activities. Satellite observations such as TROPOMI (TROPOspheric Monitoring Instrument)-derived column density data can provide spatially continuous monitoring of ground-level SO2 concentrations. This study aims to propose a 2-step residual corrected model to estimate ground-level SO2 concentrations through the synergistic use of satellite data and numerical model output. Random forest machine learning was adopted in the 2-step residual corrected model. The proposed model was evaluated through three cross-validations (i.e., random, spatial and temporal). The results showed that the model produced slopes of 1.14-1.25, R values of 0.55-0.65, and relative root-mean-square-error of 58-63%, which were improved by 10% for slopes and 3% for R and rRMSE when compared to the model without residual correction. The model performance by country was slightly reduced in Japan, often resulting in overestimation, where the sample size was small, and the concentration level was relatively low. The spatial and temporal distributions of SO2 produced by the model agreed with those of the in-situ measurements, especially over Yangtze River Delta in China and Seoul Metropolitan Area in South Korea, which are highly dependent on the characteristics of anthropogenic emission sources. The model proposed in this study can be used for long-term monitoring of ground-level SO2 concentrations on both the spatial and temporal domains.

Sentinel-1 SAR image-based waterbody detection technique for estimating the water storage in agricultural reservoirs (농업저수지의 저수량 추정을 위한 Sentinel-1 SAR 영상 기반 수체탐지 기법)

  • Jeong, Jaehwan;Oh, Seungcheol;Lee, Seulchan;Kim, Jinyoung;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.54 no.7
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    • pp.535-544
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    • 2021
  • Agricultural water occupies 48% of water demand, and management of agricultural reservoirs is essential for water resources management within agricultural basins. For more efficient use of agricultural water, monitoring the distribution of water resources in agricultural reservoirs and agricultural basins is required. Therefore, in this study, three threshold determination methods (i.e., fixed threshold, Otsu threshold, Kittler-Illingworth (KI) threshold) were compared to detect terrestrial water bodies using Sentinel-1 images for 3 years from 2018 to 2020. The purpose of this study was to evaluate methods for determining threshold values to more accurately estimate the reservoir area. In addition, by analyzing the relationship between the water surface and water storage at the Edong, Gosam, and Giheung reservoirs, water storage based on the SAR image was estimated and validated with observations. The thresholding method for detecting a waterbody was found to be the most accurate in the case of the KI threshold, and the water storage estimated by the KI threshold indicated a very high agreement (r = 0.9235, KGE' = 0.8691). Although the seasonal error characteristics were not observed, the problem of underestimation at high water levels may occur; the relationship between the water surface and the water storage could change rapidly. Therefore, it is necessary to understand the relationship between the water surface area and water storage through ground observation data for a more accurate estimation of water storage. If the use of SAR data through water resources satellites becomes possible in the future, based on the results of this study, it is judged that it will be beneficial for monitoring water storage and managing drought.

Shipping Industry Support Plan based on Research of Factors Affecting on the Freight Rate of Bulk Carriers by Sizes (부정기선 운임변동성 영향 요인 분석에 따른 우리나라 해운정책 지원 방안)

  • Cheon, Min-Soo;Mun, Ae-ri;Kim, Seog-Soo
    • Journal of Korea Port Economic Association
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    • v.36 no.4
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    • pp.17-30
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    • 2020
  • In the shipping industry, it is essential to engage in the preemptive prediction of freight rate volatility through market monitoring. Considering that freight rates have already started to fall, the loss of shipping companies will soon be uncontrollable. Therefore, in this study, factors affecting the freight rates of bulk carriers, which have relatively large freight rate volatility as compared to container freight rates, were quantified and analyzed. In doing so, we intended to contribute to future shipping market monitoring. We performed an analysis using a vector error correction model and estimated the influence of six independent variables on the charter rates of bulk carriers by Handy Size, Supramax, Panamax, and Cape Size. The six independent variables included the bulk carrier fleet volume, iron ore traffic volume, ribo interest rate, bunker oil price, and Euro-Dollar exchange rate. The dependent variables were handy size (32,000 DWT) spot charter rates, Supramax 6 T/C average charter rates, Pana Max (75,000 DWT) spot charter, and Cape Size (170,000 DWT) spot charter. The study examined charter rates by size of bulk carriers, which was different from studies on existing specific types of ships or fares in oil tankers and chemical carriers other than bulk carriers. Findings revealed that influencing factors differed for each ship size. The Libo interest rate had a significant effect on all four ship types, and the iron ore traffic volume had a significant effect on three ship types. The Ribo rate showed a negative (-) relationship with Handy Size, Supramax, Panamax, and Cape Size. Iron ore traffic influenced three types of linearity, except for Panamax. The size of shipping companies differed depending on their characteristics. These findings are expected to contribute to the establishment of a management strategy for shipping companies by analyzing the factors influencing changes in the freight rates of charterers, which have a profound effect on the management performance of shipping companies.

Overview and Prospective of Satellite Chlorophyll-a Concentration Retrieval Algorithms Suitable for Coastal Turbid Sea Waters (연안 혼탁 해수에 적합한 위성 클로로필-a 농도 산출 알고리즘 개관과 전망)

  • Park, Ji-Eun;Park, Kyung-Ae;Lee, Ji-Hyun
    • Journal of the Korean earth science society
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    • v.42 no.3
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    • pp.247-263
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    • 2021
  • Climate change has been accelerating in coastal waters recently; therefore, the importance of coastal environmental monitoring is also increasing. Chlorophyll-a concentration, an important marine variable, in the surface layer of the global ocean has been retrieved for decades through various ocean color satellites and utilized in various research fields. However, the commonly used chlorophyll-a concentration algorithm is only suitable for application in clear water and cannot be applied to turbid waters because significant errors are caused by differences in their distinct components and optical properties. In addition, designing a standard algorithm for coastal waters is difficult because of differences in various optical characteristics depending on the coastal area. To overcome this problem, various algorithms have been developed and used considering the components and the variations in the optical properties of coastal waters with high turbidity. Chlorophyll-a concentration retrieval algorithms can be categorized into empirical algorithms, semi-analytic algorithms, and machine learning algorithms. These algorithms mainly use the blue-green band ratio based on the reflective spectrum of sea water as the basic form. In constrast, algorithms developed for turbid water utilizes the green-red band ratio, the red-near-infrared band ratio, and the inherent optical properties to compensate for the effect of dissolved organisms and suspended sediments in coastal area. Reliable retrieval of satellite chlorophyll-a concentration from turbid waters is essential for monitoring the coastal environment and understanding changes in the marine ecosystem. Therefore, this study summarizes the pre-existing algorithms that have been utilized for monitoring turbid Case 2 water and presents the problems associated with the mornitoring and study of seas around the Korean Peninsula. We also summarize the prospective for future ocean color satellites, which can yield more accurate and diverse results regarding the ecological environment with the development of multi-spectral and hyperspectral sensors.

A Study on the Protection of Personal Information in the Medical Service Act (의료법의 개인정보보호에 관한 연구)

  • Sung, Soo-Yeon
    • The Korean Society of Law and Medicine
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    • v.21 no.2
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    • pp.75-103
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    • 2020
  • There is a growing voice that medical information should be shared because it can prepare for genetic diseases or cancer by analyzing and utilizing medical information in big data or artificial intelligence to develop medical technology and improve patient care. The utilization and protection of patients' personal information are the same as two sides of the same coin. Medical institutions or medical personnel should take extra caution in handling personal information with high environmental distinct characteristics and sensitivity, which is different from general information processors. In general, the patient's personal information is processed by medical personnel or medical institutions through the processes of collection, creation, and destruction. Still, the use of terms related to personal information in the Medical Service Act is jumbled, or the scope of application is unclear, so it relies on the interpretation of precedents. For the medical personnel or the founder of the medical institution, in the case of infringement of Article 24(4), it cannot be regarded that it means only medical treatment information among personal information, whether or not it should be treated the same as the personal information under Article 23, because the sensitive information of patients is recorded, saved, and stored in electronic medical records. Although the prohibition of information leakage under Article 19 of the Medical Service Act has a revision; 'secret' that was learned in business was revised to 'information', but only the name was changed, and the benefit and protection of the law is the same as the 'secret' of the criminal law, such that the patient's right to self-determination of personal information is not protected. The Privacy Law and the Local Health Act consider the benefit and protection of the law in 'information learned in business' as the right to self-determination of personal information and stipulate the same penalties for personal information infringement such as leakage, forgery, alteration, and damage. The privacy regulations of the Medical Service Act require that the terms be adjusted uniformly because the jumbled use of terms can confuse information subjects, information processors, and shows certain limitations on the protection of personal information because the contents or scope of the regulations of the Medical Service Law for special corporations and the Privacy Law may cause confusion in interpretation. The patient's personal information is sensitive and must be safely protected in its use and processing. Personal information must be processed in accordance with the protection principle of Privacy Law, and the rights such as privacy, freedom, personal rights, and the right to self-determination of personal information of patients or guardians, the information subject, must be guaranteed.

A Study of Chinese Translation and Reader Reception of the Modern Korean Novel, Focusing on the Last 5 Years (한국현대소설의 중국어번역현황 및 독자수용양상 고찰 - 최근 5년간을 중심으로)

  • Choi, Eun-Jeong
    • Cross-Cultural Studies
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    • v.43
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    • pp.429-457
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    • 2016
  • This article is an analysis of the status of the modern Korean novels translated into Chinese over the past five years and how they are perceived by readers. Translation of modern Korean novels over the past five years has a few important characteristics as the following. The first characteristic is diversity. Books written by the most representative modern Korean writers, like Lee Gwang-soo, Kim Yu-jung, Kim Dong-ri, and books of the authors with very unique ideas, such as Park Kyung-ri, Lee Mun-yeol, Shin Kyung-suk, Gong Ji-young, Kim Young-ha, Park Min-kyu, Cheon Myung-gwan, and Kim Ae-ran have been translated and introduced to the Chinese population. Secondly, there are active translation of the books written by female writers. Lastly, without the support of the Literature Translation Institute of Korea or the Daesan Foundation, the number of works translated and published is slowly increasing. As a result of the increasing number of translations, the quality of translation is improving. However, interest on the part of Chinese readers in the modern Korean novel is not very high. But, the works of authors like Kim Young-ha, Cheon Myung-gwan, Kim Ae-ran, and Park Min-kyu, who began their literary careers after the mid-90s, are drawing relatively more attention. The common features of such works are the novelty of the narrative methods, attachment to reality, and readability. The interest shown by Chinese readers is significant in explaining the two following factors. First, it is true that many modern Korean novels are available in China, but only those that have been read will continue to be read. Second, the indifference of Chinese readers to modern Korean novels is because they are not yet aware of the existence of such works. It is important to train professional translators who can properly translate literature and also to focus on introducing the differences in modern Korean novels through canonical translation. To achieve this aim, not only supportive policies, but also cooperation between researchers in the field of modern Korean literature, translators, and publishers is essential.

"Jungmo2501", A Winter Oat (Avena sativa L.) Cultivar of Lodging Tolerance, Early-Heading and High Forage Yield (조숙 내도복 다수성 추파용 총체귀리 품종 '중모2501')

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Park, Ki-Hun;Oh, Young-Jin;Kim, Kee-Jong;Ju, Jung-Il;Jang, Young-Jik;Park, Nam-Geon;Kim, Dea-Wook;Ku, Ja-Hwan;Kweon, Soon-Jong;Ahn, Jong-Woong
    • Korean Journal of Breeding Science
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    • v.49 no.2
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    • pp.80-86
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    • 2017
  • 'Jungmo2501' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the National Institute of Crop Science, RDA in 2010. The following is the characteristics of 'Jungmo2501' that is characterized as light green leaf, yellow brown culm and whitish yellow grain. The heading date of 'Jungmo2501' was about 3 days earlier than that of check cultivar 'Samhan'(May 7 and May 10, respectively). Its plant height was 11 cm longer than 103 cm of the check, and the leaf blade ratio of aerial parts was 26 % higher than the check (11.8% and 9.4%, respectively). The cold tolerance, resistance to lodging and wet injury of 'Jungmo2501' were similar to those of the check. The average forage dry matter yield of 'Jungmo2501' harvested at milk-ripe stage was 5% higher than the check ($15.5ton\;ha^{-1}$ and $14.7ton\;ha^{-1}$, respectively). 'Jungmo2501' was higher than the check in terms of protein content (6.6% and 5.9%, respectively), neutral detergent fiber (58.5% and 57.6%, respectively), and acid detergent fiber (34.5% and 32.1%, respectively), while total digestible nutrients was lower than the check (61.6% and 63.6%, respectively), and TDN yield was $0.37ton\;ha^{-1}$ more than that of the check ($9.71ton\;ha^{-1}$ and $9.34ton\;ha^{-1}$, respectively). The silage grade of 'Jungmo2501' estimated by Flig score showed level II, meaning good quality. Fall sowing cropping of 'Jungmo2501' is recommended only for areas where average daily minimum mean temperatures in January are higher than $-6^{\circ}C$.

The Aspects of Performance in Major Multipurpose Places during the Japanese Colonial Era - Focusing on the performance of traditional music - (일제강점기 주요 다목적 공간들에서의 공연양상 - 전통음악공연을 중심으로 -)

  • Keum, Yong-woong
    • (The) Research of the performance art and culture
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    • no.36
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    • pp.603-647
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    • 2018
  • During the Japanese colonial era, Chosun Central Young Men's Christian Association Hall, Gyeongseong Public Hall, or Bumingwan was used as multipurpose space where various performances or events were held. Although traditional music performed in each of the places did influence the remaining of traditional music in existence as well as the vitalization of traditional musicians' activity, since these places were mostly for Western music or other genres, no research has been carried out to study the performance of traditional music there in detail. The purpose of this study is to understand the aspects of performing traditional music in multipurpose places mentioned above. Reviewing newspaper materials of the time, this author has examined the aspects of performing traditional music in each of those places in terms of the forms of performances performance programs performers as well as performing groups the aspects of development. First, this researcher considered in what forms traditional music was performed in each of the places mostly. About performance programs, this author divided them into instrumental music, vocal music court music, and folk music. Regarding performers, this study divided them into instrumental music and vocal music professional performers and unprofessional performers male and female master singers and gisaeng and figured out the importance of each of them in different places. Also, concerning the appearance of performers and performing groups, this researcher studied how it was associated with the space, and about the aspects of performance, how it was developed in different periods was examined. In that process, this author has learned that the aspects of performing traditional music in the space were significantly influenced by the characteristics of each space and has clearly and concretely understood performing programs as well as the aspects of performers and groups' activity. With this research as an opportunity, this author expects that research will be actively conducted on the performance of traditional music in each of the places that have not been studied yet and it can contribute to figuring out the development or trends of performing traditional music during the Japanese colonial era.

The Influence of Daily Social Interaction and Physical Activity on Daily Happiness of Korean Urban Older Adults (도시노인의 사회적 교류, 신체활동과 일상적 행복감의 관련성: 개인특성의 맥락효과를 고려하여)

  • Han, Gyounghae;Choi, Heejin
    • 한국노년학
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    • v.38 no.4
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    • pp.1083-1105
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    • 2018
  • The present study sought to capture day-to-day fluctuation of the daily happiness among Korean urban older adults and to examine whether the within person fluctuation of daily happiness is explained by the social and physical activities the older adults experience each day. We also examined whether the within person association between daily social, physical activities and the daily happiness varies by individual characteristics(i.e. gender, age, educational level and health). In addition, we explored the relationships between the level and fluctuation of daily happiness and the level of global happiness. The data was collected by multi-method approach, which includes general survey, daily diary method and collection of physical activity data through the activity monitors. In total, 175 urban older adults participated for seven days of daily diary survey. The data about the number of steps and the time spent on sedentary activities, light intensity physical activities and moderate to vigorous intensity physical activities were also collected during the same period from 16 sub-samples using activity monitors. Hierarchical linear modeling was applied for the analysis. The results were as below. First, the level of happiness of older adults fluctuated during a week, and the patterns of fluctuation varied by the gender and the health. Second, socializing with their children and friends elevated their levels of happiness. Also the impact of contacts with siblings on the level of daily happiness was greater for the unhealthy group compare to the healthy group. Third, older adults were happier on the days when they walked more, but the level of daily happiness decreased on the days when they spent longer time for low intensity physical activities. Lastly, the higher level of daily happiness were related to the higher level of global happiness, but the degree of fluctuation of daily happiness was not related to the level of global happiness. The implications of these results and suggestions for future research are discussed.

Analysis of Application of Massive Transfusion Protocol for Trauma Patients at a Single Tertiary Referral Hospital (단일 3차 의료기관에서 외상환자에 대한 대량수혈 프로토콜 적용 분석)

  • Kim, Hyerin;Yoo, Dong-Won;Kim, Hyerim;Shin, Kyung-Hwa;Lee, Hyun-Ji;Chang, Chulhun L.;Kim, Hyung-Hoi
    • The Korean Journal of Blood Transfusion
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    • v.29 no.3
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    • pp.262-272
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    • 2018
  • Background: Massive hemorrhage due to trauma is one of the major causes of death in trauma patients, and the quick supply of appropriate blood products is critical in order to reduce the mortality rate. We introduced a massive transfusion protocol (MTP) for safe and rapid transfusion of trauma patients. Using records collected since its adoption, we compared the characteristics of MTP applied group (MTP group) and MTP not applied group (non-MTP group) to determine whether there is an indicator for predicting patients to be treated with MTP. Methods: We retrospectively reviewed the electronic medical records and laboratory findings of patients who received massive transfusions in the trauma emergency room of a single tertiary hospital from February to August 2018. We analyzed various laboratory test results, the amount and ratio of the transfused blood products, and the time required for blood products to be released for the MTP group and the non-MTP group. Results: Of the 54 trauma patients who received massive transfusions, 31 were in the MTP group and 22 in the non-MTP group. There was no significant difference in initial vital signs (except blood pressure) and laboratory test results. Also there was no difference in the amount and ratio of blood products, but the time required for blood product release was shorter in the MTP group. Conclusion: There was no significant difference in clinical findings such as initial vital signs and laboratory test results between the MTP and non-MTP groups, but required blood products were prepared and released more quickly for the MTP group.