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Present Status of the Quality Assurance and Control (QA/QC) for Korean Macrozoobenthic Biological Data and Suggestions for its Improvement (해양저서동물의 정량적 자료에 대한 정도관리 현실과 개선안)

  • CHOI, JIN-WOO;KHIM, JONG SEONG;SONG, SUNG JOON;RYU, JONGSEONG;KWON, BONG-OH
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.26 no.3
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    • pp.263-276
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    • 2021
  • Marine benthic organisms have been used as the indicators for the environment assessment and recently considered as a very important component in the biodiversity and ecosystem restoration. In Korean waters, the quantitative data on marine benthos was used as one of major components for the marine pollution assessment for 50 years since 1970s. The species identification which is an important factor for the quantitative biological data was mainly performed by the marine benthic ecologists. This leads to the deterioration of the data quality on marine benthos from the misidentication of major taxonomic groups due to the lack of taxonomic expertise in Korea. This taxonomic problem has not been solved until now and remains in most data from national research projects on the marine ecosystems in Korean waters. Here we introduce the quality assurance and control (QA/QC) system for the marine biological data in UK, that is, NMBAQC (Northeast Atlantic Marine Biological Analytic and Quality Control) Scheme which has been performed by private companies to solve similar species identification problems in UK. This scheme asks for all marine laboratories which want to participate to any national monitoring programs in UK to keep their identification potency at high level by the internal quality assurance systems and provides a series of taxonomic workshops and literature to increase their capability. They also performs the external quality control for the marine laboratories by performing the Ring Test using standard specimens on various faunal groups. In the case of Korea, there are few taxonomic expertise in two existing national institutions and so they can't solve the taxonomic problems in marine benthic fauna data. We would like to provide a few necessary suggestions to solve the taxonomic problems in Korean marine biological data in short-terms and long-terms: (1) the identification of all dominant species in marine biological data should be confirmed by taxonomic expertise, (2) all the national research programs should include taxonomic experts, and (3) establishing a private company, like the Korea marine organism identification association (KMOIA), which can perform the QA/QC system on the marine organisms and support all Korean marine laboratories by providing taxonomic literature and species identification workshops to enhance their potency. The last suggestion needs more efforts and time for the establishment of that taxonomic company by gathering the detailed contents and related opinions from diverse stakeholders in Korea.

LSTM Based Prediction of Ocean Mixed Layer Temperature Using Meteorological Data (기상 데이터를 활용한 LSTM 기반의 해양 혼합층 수온 예측)

  • Ko, Kwan-Seob;Kim, Young-Won;Byeon, Seong-Hyeon;Lee, Soo-Jin
    • Korean Journal of Remote Sensing
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    • v.37 no.3
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    • pp.603-614
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    • 2021
  • Recently, the surface temperature in the seas around Korea has been continuously rising. This temperature rise causes changes in fishery resources and affects leisure activities such as fishing. In particular, high temperatures lead to the occurrence of red tides, causing severe damage to ocean industries such as aquaculture. Meanwhile, changes in sea temperature are closely related to military operation to detect submarines. This is because the degree of diffraction, refraction, or reflection of sound waves used to detect submarines varies depending on the ocean mixed layer. Currently, research on the prediction of changes in sea water temperature is being actively conducted. However, existing research is focused on predicting only the surface temperature of the ocean, so it is difficult to identify fishery resources according to depth and apply them to military operations such as submarine detection. Therefore, in this study, we predicted the temperature of the ocean mixed layer at a depth of 38m by using temperature data for each water depth in the upper mixed layer and meteorological data such as temperature, atmospheric pressure, and sunlight that are related to the surface temperature. The data used are meteorological data and sea temperature data by water depth observed from 2016 to 2020 at the IEODO Ocean Research Station. In order to increase the accuracy and efficiency of prediction, LSTM (Long Short-Term Memory), which is known to be suitable for time series data among deep learning techniques, was used. As a result of the experiment, in the daily prediction, the RMSE (Root Mean Square Error) of the model using temperature, atmospheric pressure, and sunlight data together was 0.473. On the other hand, the RMSE of the model using only the surface temperature was 0.631. These results confirm that the model using meteorological data together shows better performance in predicting the temperature of the upper ocean mixed layer.

A Study on the Hydraulic Factors of Groundwater Level Fluctuation by Region in Jeju Island (제주도 지역별 지하수위 변동 요인에 대한 고찰)

  • Jeong, Jiho;Park, Jaesung;Koh, Eun-hee;Park, Won-bae;Jeong, Jina
    • The Journal of Engineering Geology
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    • v.32 no.2
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    • pp.257-270
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    • 2022
  • This study evaluated the hydraulic factors contributing to the decreasing groundwater levels across Jeju island. Time-series data for groundwater level, precipitation, and groundwater usage and information on land use were acquired, and the correlations among them were analyzed to evaluate the causes of the decreasing groundwater. The effects of precipitation and groundwater usage on the fluctuations of groundwater level were quantified using response surface analysis and sensitivity analysis, and methods for groundwater quantity management by region were proposed. The results showed that the rate of groundwater decrease in the western region was larger than that in the eastern region. For the eastern region, the influence of precipitation was large and the rate of decrease in the groundwater level was relatively small. The geological formation of this part of the island and continuous seawater intrusion suggest that although the absolute amount of groundwater extracted for use was large, the decrease in the groundwater level was not seen to be great due to an increase in pressure by seawater intrusion. Overall, precipitation and groundwater usage had the greatest effect on the amount of groundwater in the western region, and thus their data would be most useful for informing groundwater management, whereas other factors (e.g., sea level and the location of the freshwater-seawater transition zone) must be considered when understanding Jeju's eastern region. As the characteristics of groundwater level fluctuations in the eastern and western regions are distinct, an optimal management plan for each region should be proposed to ensure the efficient management of groundwater quantity.

A Study on the Measurement of Startup and Venture Ecosystem Index (창업·벤처 생태계 측정에 관한 연구)

  • Kim, Sunwoo;Jin, Wooseok;Kwak, Kihyun;Ko, Hyuk-Jin
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.6
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    • pp.31-42
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    • 2021
  • The importance of startups and ventures in the Korean economy is growing. This study measured whether the start-up and venture ecosystem is growing, including the growth of startups and ventures. The startup and venture ecosystem consists of startups and ventures, investors, and government, which are the main actors of the 'ecosystem', and their movements were measured with 25 quantitative indicators. Based on the original data of the time series from 2010 to 2020, the startup and venture ecosystem index was calculated by applying weights through the comprehensive stock index method and AHP. In 2020, the startup and venture ecosystem grew 2.9 times compared to 2010, and the increase in the government index had a significant impact on growth. Also, the individual indicators that make up each index in 2020, the corporate index had the greatest impact on the growth of the number of 100-billion ventures, while the investment index had a recovery amount and the government index had a significant impact. Based on the original data, the startup and venture ecosystem index was analyzed by dividing it into ecosystems (startup ecosystem and venture ecosystem), industry by industry (all industries and manufacturing industry), and region (Korea and Busan). As a result, the growth of the startup ecosystem over the past decade has been slightly larger than that of the venture ecosystem. The manufacturing was lower than that of all industries, and Busan was lower than that of the nation. This study was intended to use it for the establishment and implementation of support policies by developing, measuring, and monitoring the startup and venture ecosystem index. This index has the advantage of being able to research the interrelationships between major actors, and anyone can calculate the index using the results of official statistical surveys. In the future, it is necessary to continuously update this content to understand how economic and social events or policy support have affected the startup and venture ecosystem.

Analysis of Causality of the Increase in the Port Congestion due to the COVID-19 Pandemic and BDI(Baltic Dry Index) (COVID-19 팬데믹으로 인한 체선율 증가와 부정기선 운임지수의 인과성 분석)

  • Lee, Choong-Ho;Park, Keun-Sik
    • Journal of Korea Port Economic Association
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    • v.37 no.4
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    • pp.161-173
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    • 2021
  • The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.

A Study on the Sinpa of Along With the Gods and the Korean Sinpa -Focusing on the comparison between the Sinpa of Singwahamkke Jeoseung and the Sinpa of Along With the Gods: The Two Worlds (<신과함께>의 신파성과 한국적 신파 현상 -웹툰 <신과함께-저승편>과 영화 <신과함께-죄와 벌>에 나타난 신파성 비교를 중심으로)

  • Park, Jae-Yeon
    • Journal of Popular Narrative
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    • v.26 no.4
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    • pp.77-114
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    • 2020
  • This article aims to examine the Sinpa of Along With the Gods: The Two Worlds. Along with the Gods: The Two Worlds was a box office hit with a 10 million attendance mark, but it was also criticized as a 'Korean Sinpa' at the time of its release. The original version of Along with the Gods is a Webtoon called Singwahamkke in Korean. The popularity of Singwahamkke and its adaptation, Along with the Gods was enormous, which prompted a very active research to be carried about the work. However there are only a few articles which analyze the Along with the Gods: The Two Worlds focusing on the Sinpa, even though the Sinpa of the Along with the Gods: The Two Worlds was a highly controversial issue when the movie was released. In this regard, this article tries to examine the Sinpa of the Along with the Gods: The Two Worlds closely, especially by comparing it with the original webtoon Singwahamkke Jeoseung. The body part of this article is composed of three major parts: chapters 2, 3, and 4. Chapter 2 contains an in depth explanation about the notion of Sinpa, the main conceptual research tool for this study. In chapter 3, the original webtoon Singwahamkke Jeoseung is examined closely. This chapter analyzes the 'Sinpajeok moment' in Singwahamkke Jeoseung and argues that despite the presence of Sinpa elements, the webtoon cannot be considered a 'Sinpajeok text'. On the other hand the main subject of chapter 4 is discovering what effect the adaptation from webtoon to movie had on this work, with a particular focus on the gender of Sinpa and Kim Ja-hong. Chapter 5, which corresponds to the conclusion, briefly evaluates the social significance of the controversy arisen in South Korea about the Sinpa in Along with the Gods: The Two Worlds. Sinpa is one of the most repeated code in the realm of Korean popular narrative. This is why the Sinpa of contemporary text is examined continuously even though there are already plenty of studies on the Sinpa. Everyone has called Along with the Gods: The Two Worlds Sinpa but no one has properly analyzed it. It is hoped that this article which closesly examined the Sinpa in Along with the Gods: The Two Worlds contribute to the field of Sinpa. It is also expected that this article can find appropriate contextual meaning of the series of Along with the Gods.

Extreme Job, How Will We Survive Since "Candlelight Protest"? -A Revival of Comic Mode and a Comedy Film in the Age of Self-Management (<극한직업>, '촛불혁명' 이후 어떻게 버티며 살아남을 것인가? -코믹 모드의 부활과 자기경영 시대의 코미디영화)

  • Chung, Young-Kwon
    • Journal of Popular Narrative
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    • v.26 no.3
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    • pp.221-254
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    • 2020
  • This paper finds a solution in the social context which cannot be explained thoroughly by well-timed release date, revival of comedy films, and the attraction of Lee Byeong-heon's comedy etc. while it throws question of how the film, Extreme Job captivated 16 million audience. The incredible hits of Extreme Job cannot be explained by analyzing the text alone. After this essay investigates a function and a role of comedy as a public sphere, it examines people's desires and wishes in the comedy and other genres since 2008 when the conservative government has seized power. Since 2008 a series of dark tone's action thriller, social problem film, and disaster film have emerged, these genres showed absence of public security, crisis of democracy and criticism against rulling class. On the other hand, hit comedy films have showed escapism such as weepie, nostalgia, and fantasy at the same time, generally. Although Veteran (2015) is not full-blown comedy, after this film's big success, "comic mode" has gradually revived. A light tone's films which are truer to genre rules has started representing the wishes of people toward social reforms and changes. Meanwhile, "Candlelight Protest" served as a momentum to recover the democracy which has been in crisis, but it could not lead changes in economic and daily lives. Exreme Job can be read as a question how we will survive since "Candlight Protest." The lives of detectives as self-employed workers who has taken over a fried chicken restaurant for going undercover are appearances of ordinary persons who must survive in the edless conpetition. Furthermore, this film shows a dream of a "great success myth" which becomes well-known as a famous restaurant and a self-management such as brand-naming and an exapansion of franchise business. We can read ganster's chicken franchises as a huge distribution industry which disturbs market system by delivering drugs secretly. While applauses that we give to the police having identities of self-employed workers which sweeps the ganster are giving support to oridinary neighborhood like us, they are also wishes of people who long for the restoration of publicness of police in the market which is becoming increasingly privatized today. A significance of this essay is to examine Extreme Job in terms of the geography of film genres and the revival of comic mode sicne 2008 at the macro level, and is to read the film in the perspective of the problems of economic and daily lives which has been still unsolved since "Candlelight Protest" at the micro level.

A Study of Masterplot of Disaster Narrative between Korea, the US and Japan (한·미·일 재난 서사의 마스터플롯 비교 연구)

  • Park, In-Seong
    • Journal of Popular Narrative
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    • v.26 no.2
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    • pp.39-85
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    • 2020
  • This paper examines the aspects of disaster narrative, which makes the most of the concept of 'masterplot' as a narrative simulation to solve problems. By analyzing and comparing the remnants of 'masterplots' operating in the disaster narratives of Korea, the United States, and Japan, the differences between each country and social community problem recognition and resolution will be discussed. Disaster narrative is the most suitable genre for applying the 'masterplot' toward community problem solving in today's global risk society, and the problem-solving method has cognitive differences for each community. First, in the case of American disaster narratives, civilian experts' response to natural disasters tracks the changes of heroes in today's 'Marvel Comic Universe' (MCU). Compared to the past, the close relationship between heroism and nationalism has been reduced, but the state remains functional even if it is bolstered by the heroes' voluntary cooperation and reflection ability. On the other hand, in Korea's disaster narratives, the disappearance of the country and paralysis of the function are foregrounded. In order to fill the void, a new family narrative occurs, consisting of a righteous army or people abandoned by the state. Korea's disaster narratives are sensitive to changes after the disaster, and the nation's recovery never returns to normal after the disaster. Finally, Japan's disaster narratives are defensive and neurotic. A fully state-led bureaucratic system depicts an obsessive nationalism that seeks to control all disasters, or even counteracts anti-heroic individuals who reject voluntary sacrifices and even abandon disaster conditions This paper was able to diagnose the impact and value of a 'masterplot' today by comparing a series of 'masterplots' and their variations and uses. In a time when the understanding and utilization of 'masterplots' are becoming more and more important in today's world where Over-the top(OTT) services are being provided worldwide, this paper attempt could be a fragmentary model for the distribution and sharing of global stories.

Analysis of the effect of long-term water supply improvement by the installation of sand dams in water scarce areas (물부족 지역에서 샌드댐 설치에 의한 장기 물공급 개선 효과 분석)

  • Chung, Il-Moon;Lee, Jeongwoo;Lee, Jeong Eun;Kim, Il-Hwan
    • Journal of Korea Water Resources Association
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    • v.55 no.12
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    • pp.999-1009
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    • 2022
  • The Chuncheon Mullori area is an underprivileged area for water welfare that does not have a local water supply system. Here, water is supplied to the village by using a small-scale water supply facility that uses underground water and underground water as the source. To solve the problem of water shortage during drought and to prepare for the increasing water demand, a sand dam was installed near the valley river, and this facility has been operating since May 2022. In this study, in order to evaluate the reliability of water supply when a sand dam is assumed during a drought in the past, groundwater runoff simulation results using MODFLOW were used to generate inflow data from 2011 to 2020, an unmeasured period. After performing SWAT-K basin hydrologic modeling for the watershed upstream of the existing water intake source and the sand dam, the groundwater runoff was calculated, and the relative ratio of the monthly groundwater runoff for the previous 10 years to the monthly groundwater runoff in 2021 was obtained. By applying this ratio to the 2021 inflow time series data, historical inflow data from 2011 to 2020 were generated. As a result of analyzing the availability of water supply during extreme drought in the past for three cases of demand 20 m3/day, 50 m3/day, and 100 m3/day, it can be confirmed that the reliability of water supply increases with the installation of sand dams. In the case of 100 m3/day, it was analyzed that the reliability exceeded 90% only when the existing water intake source and the sand dam were operated in conjunction. All three operating conditions were evaluated to satisfy 50 m3/day or more of demand based on 95% reliability of water supply and 30 m3/day or more of demand based on 99% of reliability.

Evaluation of Temperature and Precipitation over CORDEX-EA Phase 2 Domain using Regional Climate Model HadGEM3-RA (HadGEM3-RA 지역기후모델을 이용한 CORDEX 동아시아 2단계 지역의 기온과 강수 모의 평가)

  • Byon, Jae-Young;Kim, Tae-Jun;Kim, Jin-Uk;Kim, Do-Hyun
    • Journal of the Korean earth science society
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    • v.43 no.3
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    • pp.367-385
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    • 2022
  • This study evaluates the temperature and precipitation results in East Asia simulated from the Hadley Centre Global Environmental Model version 3 regional climate model (HadGEM3-RA) developed by the UK Met Office. The HadGEM3-RA is conducted in the Coordinated Regional climate Downscaling Experiment-East Asia (CORDEX-EA) Phase II domain for 15 year (2000-2014). The spatial distribution of rainbands produced from the HadGEM3-RA by the summer monsoon is in good agreement with the Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of water resources (APRODITE) data over the East Asia. But, precipitation amount is overestimated in Southeast Asia and underestimated over the Korean Peninsula. In particular, the simulated summer rainfall and APRODITE data show the least correlation coefficient and the maximum value of root mean square error in South Korea. Prediction of temperature in Southeast Asia shows underestimation with a maximum error during winter season, while it appears the largest underestimation in South Korea during spring season. In order to evaluate local predictability, the time series of temperature and precipitation compared to the ASOS data of the Seoul Meteorological Station is similar to the spatial average verification results in which the summer precipitation and winter temperature underestimate. Especially, the underestimation of the rainfall increases when the amounts of precipitation increase in summer. The winter temperature tends to underestimate at low temperature, while it overestimates at high temperature. The results of the extreme climate index comparison show that heat wave is overestimated and heavy rainfall is underestimated. The HadGEM3-RA simulated with a horizontal resolution of 25 km shows limitations in the prediction of mesoscale convective system and topographic precipitation. This study indicates that improvement of initial data, horizontal resolution, and physical process are necessary to improve predictability of regional climate model.