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A Study on the Application of IUCN Global Ecosystem Typology Using Land Cover Map in Korea (토지피복지도를 활용한 IUCN 생태계유형분류 국내 적용)

  • Hee-Jung Sohn;Su-Yeon Won;Jeong-Eun Jeon;Eun-Hee Park;Do-Hee Kim;Sang-Hak Han;Young-Keun Song
    • Korean Journal of Environment and Ecology
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    • v.37 no.3
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    • pp.209-220
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    • 2023
  • Over the past few centuries, widespread changes to natural ecosystems caused by human activities have severely threatened biodiversity worldwide. Understanding changes in ecosystems is essential to identifying and managing threats to biodiversity. In line with this need, the IUCN Council formed the IUCN Global Ecosystem Typology (GET) in 2019, taking into account the functions and types of ecosystems. The IUCN provides maps of 10 ecosystem groups and 108 ecological functional groups (EFGs) on a global scale. According to the type classification of IUCN GET ecosystems, Korea's ecosystem is classified into 8 types of Realm (level 1), 18 types of Biome (level 2), and 41 types of Group (level 3). GETs provided by IUCN have low resolution and often do not match the actual land status because it was produced globally. This study aimed to increase the accuracy of Korean IUCN GET type classification by using land cover maps and producing maps that reflected the actual situation. To this end, we ① reviewed the Korean GET data system provided by IUCN GET and ② compared and analyzed it with the current situation in Korea. We evaluated the limitations and usability of the GET through the process and then ③ classified Korea's new Get type reflecting the current situation in Korea by using the national data as much as possible. This study classified Korean GETs into 25 types by using land cover maps and existing national data (Territorial realm: 9, Freshwater: 9, Marine-territorial: 5, Terrestrial-freshwater: 1, and Marine-freshwater-territorial: 1). Compared to the existing map, "F3.2 Constructed lacustrine wetlands", "F3.3 Rice paddies", "F3.4 Freshwater aquafarms", and "T7.3 Plantations" showed the largest area reduction in the modified Korean GET. The area of "T2.2 Temperate Forests" showed the largest area increase, and the "MFT1.3 Coastal saltmarshes and reedbeds" and "F2.2 Small permanent freshwater lakes" types also showed an increase in GET area after modification. Through this process, the existing map, in which the sum of all EFGs in the existing GET accounted for 8.33 times the national area, was modified so that the total sum becomes 1.22 times the national area using the land cover map. This study confirmed that the existing EFG, which had small differences by type and low accuracy, was improved and corrected. This study is significant in that it produced a GET map of Korea that met the GET standard using data reflecting the field conditions. 

The Infrared Medium-deep Survey. VIII. Quasar Luminosity Function at z ~ 5

  • Kim, Yongjung;Im, Myungshin;Jeon, Yiseul;Kim, Minjin;Pak, Soojong;Hyun, Minhee;Taak, Yoon Chan;Shin, Suhyun;Lim, Gu;Paek, Gregory S.H.;Paek, Insu;Jiang, Linhua;Choi, Changsu;Hong, Jueun;Ji, Tae-Geun;Jun, Hyunsung D.;Karouzos, Marios;Kim, Dohyeong;Kim, Duho;Kim, Jae-Woo;Kim, Ji Hoon;Lee, Hye-In;Lee, Seong-Kook;Park, Won-Kee;Yoon, Yongmin;Byeon, Seoyeon;Hwang, Sungyong;Kim, Joonho;Kim, Sophia;Park, Woojin
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.34.3-34.3
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    • 2020
  • Faint z ~ 5 quasars with M1450 ~ -23 mag are known to be the potentially important contributors to the ultraviolet ionizing background in the post-reionization era. However, their number density has not been well determined, making it difficult to assess their role in the early ionization of the intergalactic medium (IGM). In this work, we present the updated results of our z ~ 5 quasar survey using the Infrared Medium-deep Survey (IMS), a near-infrared imaging survey covering an area of 85 square degrees. From our spectroscopic observations with the Gemini Multi-Object Spectrograph (GMOS) on the Gemini-South 8 m Telescope, we discovered eight new quasars at z ~ 5 with -26.1 ≤ M1450 ≤ -23.3. Combining our IMS faint quasars with the brighter Sloan Digital Sky Survey (SDSS) quasars, we derive, for the first time, the z ~ 5 quasar luminosity function (QLF) without any fixed parameters down to the magnitude limit of M1450 = -23 mag. We find that the faint-end slope of the QLF is very flat (-1.2) with a characteristic luminosity of -25.7 mag. The number density of z ~ 5 quasars from the QLF gives lower ionizing emissivity and ionizing photon density than those in previous works. These results imply that quasars are responsible for only 10-20% of the photons required to completely ionize the IGM at z ~ 5, disfavoring the idea that quasars alone could have ionized the IGM at z ~ 5.

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Effects on Ginseng Growth and Ginsenoside Content in ICT-based Process Cultivation and Conventional Cultivation (ICT 기반의 공정재배와 관행재배에 있어서 인삼 생장 및 진세 노사이드 함량에 미치는 영향)

  • Kwang Jin Chang;Yeon Bok Kim;Hyun Jung Koo;Hyun Jin Baek;Eui Gi Hong;Su Bin Lee;Jeei Hye Choi;Hyo Yeon Son;Tae Young Kim;Dong Hyun Kim
    • Journal of Practical Agriculture & Fisheries Research
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    • v.25 no.2
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    • pp.12-19
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    • 2023
  • This study conducted an experiment with EC 1.0ms/cm ratio and excellent soil conditions for germination in ICT-based ginseng process cultivation. The first growth survey was conducted before transplantation of ginseng 1-year roots grown by seeding ginseng in the process cultivation, conventional cultivation and a second growth comparison survey was conducted after 3 months of growth. In the results, it was confirmed that ginseng grown in the process cultivation grew more than in the field. As a result of comparing the contents of 11 ginsenosides of 1-year and 2-year-old ginsenosides in the process cultivation and conventional cultivation ginseng, it was confirmed that the content of the process cultivation ginseng was higher than that of practice cultivation ginseng. In conclusion, conventional cultivation ginseng grows due to various factors under the natural cultivation environment, but process cultivation can secure the growth stability of ginseng by allowing stable soil and environmental control, so continuous research is needed in the future.

Assessing the Sensitivity of Runoff Projections Under Precipitation and Temperature Variability Using IHACRES and GR4J Lumped Runoff-Rainfall Models (집중형 모형 IHACRES와 GR4J를 이용한 강수 및 기온 변동성에 대한 유출 해석 민감도 평가)

  • Woo, Dong Kook;Jo, Jihyeon;Kang, Boosik;Lee, Songhee;Lee, Garim;Noh, Seong Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.1
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    • pp.43-54
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    • 2023
  • Due to climate change, drought and flood occurrences have been increasing. Accurate projections of watershed discharges are imperative to effectively manage natural disasters caused by climate change. However, climate change and hydrological model uncertainty can lead to imprecise analysis. To address this issues, we used two lumped models, IHACRES and GR4J, to compare and analyze the changes in discharges under climate stress scenarios. The Hapcheon and Seomjingang dam basins were the study site, and the Nash-Sutcliffe efficiency (NSE) and the Kling-Gupta efficiency (KGE) were used for parameter optimizations. Twenty years of discharge, precipitation, and temperature (1995-2014) data were used and divided into training and testing data sets with a 70/30 split. The accuracies of the modeled results were relatively high during the training and testing periods (NSE>0.74, KGE>0.75), indicating that both models could reproduce the previously observed discharges. To explore the impacts of climate change on modeled discharges, we developed climate stress scenarios by changing precipitation from -50 % to +50 % by 1 % and temperature from 0 ℃ to 8 ℃ by 0.1 ℃ based on two decades of weather data, which resulted in 8,181 climate stress scenarios. We analyzed the yearly maximum, abundant, and ordinary discharges projected by the two lumped models. We found that the trends of the maximum and abundant discharges modeled by IHACRES and GR4J became pronounced as changes in precipitation and temperature increased. The opposite was true for the case of ordinary water levels. Our study demonstrated that the quantitative evaluations of the model uncertainty were important to reduce the impacts of climate change on water resources.

Development of 1ST-Model for 1 hour-heavy rain damage scale prediction based on AI models (1시간 호우피해 규모 예측을 위한 AI 기반의 1ST-모형 개발)

  • Lee, Joonhak;Lee, Haneul;Kang, Narae;Hwang, Seokhwan;Kim, Hung Soo;Kim, Soojun
    • Journal of Korea Water Resources Association
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    • v.56 no.5
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    • pp.311-323
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    • 2023
  • In order to reduce disaster damage by localized heavy rains, floods, and urban inundation, it is important to know in advance whether natural disasters occur. Currently, heavy rain watch and heavy rain warning by the criteria of the Korea Meteorological Administration are being issued in Korea. However, since this one criterion is applied to the whole country, we can not clearly recognize heavy rain damage for a specific region in advance. Therefore, in this paper, we tried to reset the current criteria for a special weather report which considers the regional characteristics and to predict the damage caused by rainfall after 1 hour. The study area was selected as Gyeonggi-province, where has more frequent heavy rain damage than other regions. Then, the rainfall inducing disaster or hazard-triggering rainfall was set by utilizing hourly rainfall and heavy rain damage data, considering the local characteristics. The heavy rain damage prediction model was developed by a decision tree model and a random forest model, which are machine learning technique and by rainfall inducing disaster and rainfall data. In addition, long short-term memory and deep neural network models were used for predicting rainfall after 1 hour. The predicted rainfall by a developed prediction model was applied to the trained classification model and we predicted whether the rain damage after 1 hour will be occurred or not and we called this as 1ST-Model. The 1ST-Model can be used for preventing and preparing heavy rain disaster and it is judged to be of great contribution in reducing damage caused by heavy rain.

A Study on the Direction of Planting Renewal in the Green Area of Seoul Children's Grand Park Reflecting Functional Changes (기능변화를 반영한 서울어린이대공원 조성녹지의 식재 리뉴얼 방향성 연구)

  • Park, Jeong-Ah;Han, Bong-Ho;Park, Seok-Cheol
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.3
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    • pp.21-36
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    • 2023
  • As a solution to environmental issues, such as climate change response, the carbon neutrality strategy, urban heat islands, fine dust, and biodiversity enhancement, the value of urban green spaces and trees are becoming important, and various studies dealing with the effects of trees for environmental improvement are being conducted. This study comprehensively considers the preceding studies on planting tree species, planting structure, planting density, and planting base to propose a direction for the planting renewal of green areas in urban parks and applies the findings to a renewal plan to improve the urban environment through landscaping trees. A field survey was conducted on the planting status of Seoul Children's Grand Park, a large-scale neighborhood park in Seoul, and based on the survey data, a planting function evaluation was conducted, and areas needing improvement in planting function were identified. The planting function evaluation was carried out considering the park function setting, planting concept according to spatial function, and planting status. As a result of the study, the direction of planting renewal according to functional change was derived for each stage of planting function evaluation. Increasing the green area ratio is a priority in setting up park functions, but user convenience should also be considered. As a concept of planting, visual landscape planting involves planting species with beautiful tree shapes, high carbon absorption, and fine dust reduction effects. Ecological landscape planting should create a multi-layered planting site on a slope. Buffer planting should be created as multi-layered forests to improve carbon absorption and fine dust reduction effects. Green planting should consist of broad-leaved trees and herbaceous layers and aim for the natural planting of herbaceous species. For plant species, species with high urban environment improvement effects, local native species, and wild bird preferred species should be selected. As for the planting structure, landscape planting sites and green planting sites should be composed of trees, shrubs, and trees and herbaceous layers that emphasize ecology or require multi-layered buffer functions. A higher standard is applied based on the planting interval for planting density. Installing a rainwater recycling facility and using soil loam for the planting base improves performance. The results of this study are meaningful in that they can be applied to derive areas needing functional improvement by performing planting function evaluation when planning planting renewal of aging urban parks and can suggest renewal directions that reflect the paradigm of functional change of created green areas.

Ecological Studies of the Field Mouse (들쥐의 生態學的 硏究)

  • Kang, Soo Won
    • The Korean Journal of Zoology
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    • v.14 no.2
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    • pp.57-74
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    • 1971
  • The present investigation has been done to observe the ecological habits of field mice to protect the rice from damages during the growing season in paddy-field and during the storge period. The results obtained are summarized as follows: 1. Of 155 mice captured in the period of April-November 1970, which belong to four genera (Apodemus, Cricetulus, Rattus, and Micromys), 148 mice(95%) were found as striped field mice (Apodemus agrarius coreae). The population density of striped field mouse was revealed by the present study as 55/ha, which is quite a low level compared with that in Japan of 900/ha. 2. The age distribution of the mice as judged by their body weight was found mainly composed of adult and the sex ratio was found to be 1.8 as determined with 147 individuals. The nest was found to be occupied by an adult and was composed of at least three openings and more than one food storage tunnels. The mice usually keep hulled rice rather than unhulled one in storage tunnel. The weight of food found in a nest was about 50 grams on an average. 3. The mice show a most active behaviour 1-2 hours after the sunset, around midnight, and an hour before the sunrise, but they are active even in daytime in order for searching for food and for breeding. 4. The ratio (%) of damage appeared in high stem of sweet corn in August was 30 ~ 40 percent, whereas that in low stem was 80 ~ 90 percent. The weight of spoiled grains in paddy-field was 11, 400gm/0.4ha and this gives an estimate of 349, 695 for whole country. 5. The female striped field mouse weighs average of about 30 grams and gives birth to average of 4.8 younglings which wean away from female mouse three weeks after delivery. 6. The natural enemies to the mice are found to be carnivores (weasel, cat, mountain cat, fox, raccoon, and otter), raptatores(eagle, owl, kete, buzzard), and snakes. Two kinds of field rats(Rattus norvegicus, Cricetulus tritor) are also the predator to the mice. 7. The feeding preference of striped field mice follows in decreasing order of sweet corn, soybean, sweet potatoes, chestnut, and wheat. The mice do not have a preference for barley, millet, rough millet, red bean, and green bean. 8. The starvation experiment, in which water alone was supplied, revealed that the mice in good physical and nutritional conditions survived for 71 ~ 79 hours, whereas those in worse conditions survived for only 32 ~ 39 hours.

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An Unthinking Sage? Plotinus' Model of Non-Deliberative Action (생각하지 않는 현자(賢者)? 플로티누스의 비-숙고적 행동 모델)

  • Song, Euree
    • Journal of Korean Philosophical Society
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    • no.125
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    • pp.63-89
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    • 2019
  • The aim of this paper is to examine the so-called theory of automatic action attributed to Plotinus, according to which the sage can act automatically without deliberation or reasoning. Concerns were raised that such a theory runs the risk of turning the agent into an automaton by reducing action to mechanical reflexes to external stimuli. I attempt to show that Plotinus does not hold a theory of automatic action by arguing that the Plotinian sage's non-deliberative action is not automatic at all. For this purpose, I first draw attention to the non-deliberative action of the World-Reason (i.e. the reason of the World-Soul), which is supposed to present an ideal model of action. Indeed, Plotinus mentions that the World-Reason rules the world "as if automatically". This is, however, meant to indicate the spontaneous and natural manner in which the World-Reason rules. In this respect, the way the World-Reason works is compared to the way nature (i.e. the productive power of the World-Soul) works. But Plotinus points out that the World-Reason knows what to do, whereas nature works without knowing. In this connection, Plotinus makes it clear that the World-Reason does not calculate or deliberate about what to do because it already knows it. To clarify this point, I turn to Plotinus' analogy of practical wisdom (phronêsis) and skill, according to which the World-Reason is compared to an accomplished craftsman or artist, who confidently works without any doubt, hesitation or difficulty, thereby expressing her intelligence, unmediated by deliberation. From this perspective, non-deliberative action according to practical wisdom turns out to be superior to deliberative action. Plotinus admits that there are difficult circumstances in which even the skilled craftsman, unlike the World-Reason who always controls the whole situation, needs to deliberate or calculate, but he is nevertheless confident that the craftsman easily finds the solution. This suggests that the sage, who possesses practical wisdom, can act normally like a great master or virtuoso without deliberation, but in an emergency situation he also employs deliberation, but resourcefully and creatively responds to challenge. The attempt is made to elucidate the Plotinian model of sage's action with the help of Csikzentmihalyi's concept of 'flow' and Annas' application of it to the analogy of virtue and skill. Finally, it is shown that the sage's virtuous action, in spite of being a habituated action, is not a passive, routinized, automatic action, but an active, flexible, intelligent action.

A Study on Conceptual Suitability or Unfitness of 'Silhak' ('실학實學' 개념의 적합성 또는 부적합성에 관한 연구)

  • Kang, Jeong-Hoo
    • Journal of Ethics
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    • no.88
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    • pp.103-122
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    • 2013
  • This paper aims to study on conceptual suitability or unfitness of Silhak(實學). It is general that by criticizing Chujahak(朱子學) or beyond the limitation of Seonglihak(性理學), Silhak has developed practical tendency to reforming the society in the middle and end of Chosen Dynasty, related to the context of Korean national reflection in modern times. However, it is unfortunate to be understood. As presented in Chosenwangjosillok(『朝鮮王朝實錄』), there has been a few usages in the term 'Silhak'. In short, it was different from its contemporary meaning. At that time, it was usually used to have the meaning of Gyunghak(經學), compared to Sajanghak(詞章學), or rarely, of 'the true study' or 'the practical study'. Therefore, it is to claim that its conception has been manipulated or exaggerated very seriously. Since 1930s, in particular, its conception has been misused in interpreting works of Jung Yak-Yong by some scholars, such as Jung In-Bo, Moon Il-Pyung and An Jae-Hong, who tried to apply the term to overcome the Japanese colonial era symbolised as modernity based on the future life of Korea. Even though their attempt has led to have crucial discussions on the conceptions of Silhak, it has an unnecessary result that there has been a new and totally different understanding of Silhak in South Korea, North Korea, China, Japan, etc., which means that the unsustainable conception of Silhak has been one of major problems in studying of Silhak. To give an practical solution, I would try to make sense of 'time spirit' whose scholars studied Silhak in the middle and end of Chosen Dynasty. A problem, however, is that a scholar group in the name of Bukhakpa(北學派) had certain links and bonds. This is because many scholars studying of Silhak were usually features out of the main stream, which made them it difficult to form any various groups. That is to say, it seems to be natural that they have dreamed of utopian imaginations less than of overlapping points in reality. To sum up, it would be concluded at least that any approach to human lives and thoughts in the given conceptions of Silhak, e.g. ethical thoughts of Silhak, enables us to be indifferentiated to take its true meaning and time spirit of Chosen Dynasty. To be disenchanted of its social roles in Chosen Dynasty, fundamentally, it should be escaped from the wrong net of illusions and sings in understanding Silhak in certain eclectic steps.

A Study on the Environmental Instruction focused on ethical inquiry in elementary school (윤리적 탐구 중심의 초등 도덕과 환경수업)

  • Song, Youngmin
    • The Journal of Korean Philosophical History
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    • no.28
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    • pp.87-116
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    • 2010
  • In elementary, environmental education have been doing in various subjects. The features of environmental instruction would be reflected on contents of environmental education and characteristics of each subjects. These contents of environmental education might be contained normative contents, and it is moral subject that treats these normative contents systematically. Then environmental instruction of moral subject in elemental school should be approach and inquire teaching contents related to environment education. In elementary school curriculum of moral subject, teaching contents related to environment are 'preciousness of life' and 'right views of Nature and protection of the environment'. By these contents, moral instruction can approach to life of animal and plants centered on the reason to take them preciously and relation between nature and humans centered on the moral consideration. It is a difference that approaches to the environmental education not by factual understanding but by normative understanding in moral instruction. It must be focused on ethical inquiry for normative approach and reserving identity of moral subject. Necessary conditions for ethical inquiry to the environmental instruction are moral status of things besides humans. For the ethical inquiry to the moral status of nature environments, teachers could be set the logic of instruction based on the developments of environmental ethics. Formal cohesiveness of environmental instruction could be developed in sequence of ethical inquiry on moral status to the life of animal, life of plants, and whole system of nature. For this, teacher could reflect on their instruction focused on some explanations. That is, it is explanation to the animal life based on the individual-extended human oriented ethics for human, plants life based on the individual-non human oriented ethics, whole natural system based on the holistic-non human oriented ethics. When teachers reflect these explanation, they can compose their instruction as 'finding something in common with humans and animals', 'reflection on the attitude to the commons', 'thinking about reasons on the different attitudes to the commons', 'the things that disappear as plants die', 'thinking on values about non organism'. These plan of instruction could be critically reconstruct by other teachers. But environmental consciousness by ethical inquiry should be hold on instruction to the environment reflected on identity of moral subject.