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The Effect of Carbon Dioxide Leaked from Geological Storage Site on Soil Fertility: A Study on Artificial Leakage (지중 저장지로부터 누출된 이산화탄소가 토양 비옥도에 미치는 영향: 인위 누출 연구)

  • Baek, Seung Han;Lee, Sang-Woo;Lee, Woo-Chun;Yun, Seong-Taek;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.54 no.4
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    • pp.409-425
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    • 2021
  • Carbon dioxide has been known to be a typical greenhouse gas causing global warming, and a number of efforts have been proposed to reduce its concentration in the atmosphere. Among them, carbon dioxide capture and storage (CCS) has been taken into great account to accomplish the target reduction of carbon dioxide. In order to commercialize the CCS, its safety should be secured. In particular, if the stored carbon dioxide is leaked in the arable land, serious problems could come up in terms of crop growth. This study was conducted to investigate the effect of carbon dioxide leaked from storage sites on soil fertility. The leakage of carbon dioxide was simulated using the facility of its artificial injection into soils in the laboratory. Several soil chemical properties, such as pH, cation exchange capacity, electrical conductivity, the concentrations of exchangeable cations, nitrogen (N) (total-N, nitrate-N, and ammonia-N), phosphorus (P) (total-P and available-P), sulfur (S) (total-S and available-S), available-boron (B), and the contents of soil organic matter, were monitored as indicators of soil fertility during the period of artificial injection of carbon dioxide. Two kinds of soils, such as non-cultivated and cultivated soils, were compared in the artificial injection tests, and the latter included maize- and soybean-cultivated soils. The non-cultivated soil (NCS) was sandy soil of 42.6% porosity, the maize-cultivated soil (MCS) and soybean-cultivated soil (SCS) were loamy sand having 46.8% and 48.0% of porosities, respectively. The artificial injection facility had six columns: one was for the control without carbon dioxide injection, and the other five columns were used for the injections tests. Total injection periods for NCS and MCS/SCS were 60 and 70 days, respectively, and artificial rainfall events were simulated using one pore volume after the 12-day injection for the NCS and the 14-day injection for the MCS/SCS. After each rainfall event, the soil fertility indicators were measured for soil and leachate solution, and they were compared before and after the injection of carbon dioxide. The results indicate that the residual concentrations of exchangeable cations, total-N, total-P, the content of soil organic matter, and electrical conductivity were not likely to be affected by the injection of carbon dioxide. However, the residual concentrations of nitrate-N, ammonia-N, available-P, available-S, and available-B tended to decrease after the carbon dioxide injection, indicating that soil fertility might be reduced. Meanwhile, soil pH did not seem to be influenced due to the buffering capacity of soils, but it is speculated that a long-term leakage of carbon dioxide might bring about soil acidification.

A Study on the Trend of Stone Industry and Residue (석재 산업 및 부산물 동향 조사)

  • Chea, Kwang-Seok;Lee, Young Geun;Koo, Namin;Youn, Hojoong;Lim, Jong-Hwan
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.1
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    • pp.1-12
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    • 2022
  • Stone has been used for various purposes, such as for building stones, megaliths, ornamental stones, hunting and grinding throughout history. The global stone production amounted to around 153 million tons in 2018 excluding quarry waste, up 0.8% on year. Of them, stone residues accounted for 71%. The worldwide stone trading decreased 1.5 million tons to 56.5 million tons in 2018. The average price of stone was 34.1 USD per square meter, down 2.5% from the previous year. It's down 7% when only considering trading between the world's top twelve exporters. But in the three leading countries, Italy, Greece and Brazil, the price saw a sharp increase. In 2018, stone imports and exports totaled 815 million square meters, raising over 20 billion USD of revenue. Imports were largely led by six countries: China, Italy, Turkey, India, Brazil, Spain and Portugal, from largest to smallest.) In terms of stone use per 1,000 population, it was 117 square meters in 2001, and it increased to 264 square meters in 2017 and 266 square meters in 2018. The volume more than doubled during the period, but it has been declining slightly in recent years. China, India, Saudi Arabia and Belgium were the only countries that the stone use per 1,000 population exceeded 1,000 square meters. The increase rate was steepest in China, India and the United States, from largest to smallest. The global stone production is likely to grow to 69.85 million tons by 2025, despite the global economic downturn.

A Study on the Naejeong (內庭) of Daesoon Jinrihoe Temple Complexes: Focusing on Literary Sources and Context (대순진리회 도장 건축물 내정(內庭)에 대한 연구 - 내정의 문헌 출처와 그 맥락을 중심으로 -)

  • Cha, Seon-keun
    • Journal of the Daesoon Academy of Sciences
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    • v.37
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    • pp.1-52
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    • 2021
  • The Naejeong, the inner court, which is one of the structures found in the temple complexes of Daesoon Jinrihoe. It serves the function of leading and controlling the operation and direction of Korean religions in general. Considering that the dictionary meaning of 'Naejeong' is 'a place to manage the affairs of the state from inside a palace,' the name and function of the structure appear to be in harmony. However, in the Daesoon Jinrihoe context, it is said that the name 'Naejeong (內庭 'Neiting' in Chinese)' is related to a verse from a Daoist scripture. It has not been revealed whether or not the scripture is historical, and what contents or contextual meanings it contains. This study tries to pursue this matter and introduce the original source of the Naejeong in Daesoon Jinrihoe as likely coming from Qianbapinxianjing (前八品仙經, The Former Scripture of the Eight Phases That Reveal the Means to Acquire Immortality). This scripture was compiled in Lüzu-quanshu(呂祖全書, The Entire Collection of Ancestor Lü). This text and its contextual meanings will also be examined. The origin of Qianbapinxianjing dates back to either the late Ming Dynasty or the early Qing. In those days, there existed a group of literati who worshipped Ancestor Lü because he had saved people and taught the art of immortality. The group organized Daoist Spirit-Writing Altars (鸞壇道敎) and invoked the spirit of Ancestor Lü. They were said to have been taught through messages received from spirit-writing sessions (降乩) with Ancestor Lü and several Daoist scriptures were composed by them in this manner. At Immortals-Gathering Pavilion (集仙樓) of Wandian (萬店) in Guangling (廣陵), China, some literati in that group conducted a spirit-writing session with Ancestor Lü between 1589 and 1626, and they produced a scripture which contained the passage, "A crow and a rabbit gather in the middle valley (烏兎結中谷) while a turtle entwined with a snake is in the inner court (龜蛇盤內庭)." They titled the scripture, The Five Movements and Filial Piety (五行端孝). This passage symbolically expresses the accomplishment of immortality in Neidan (internal alchemy) which, within the human body, combines the two energies of yin and yang which are Water and Fire in the Five Movements scheme. This kind of cultivation is said to be achieved only by maintaining the highest possible degree of filial piety. In this context, the Naejeong where a turtle is entwined with a snake (龜蛇合體) was a term that symbolically depicted a place wherein one transforms into an immortal through cultivation. The Five Movements and Filial Piety was included in Qianbapinxianjing after it had been compiled with the other scriptures containing Ancestor Lü's teachings. In 1744, Qianbapinxianjing was included in Lüzu-quanshu, the entire 32-volume collection of Ancestor Lü and printed for the first time. This underlies the belief in Ancestor Lü (呂祖信仰) which embraces the idea of the redemption of people, teaches the arts of immortality, and features Daoist Spirit-Writing Altars, filial piety, the art of Neidan, and the combination of Water and Fire.

Evaluating efficiency of Vertical MLC VMAT plan for naso-pharyngeal carcinoma (비인두암 Vertical MLC VMAT plan 유용성 평가)

  • Chae, Seung Hoon;Son, Sang Jun;Lee, Je Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.33
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    • pp.127-135
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    • 2021
  • Purpose : The purpose of the study is to evaluate the efficiency of Vertical MLC VMAT plan(VMV plan) Using 273° and 350° collimator angle compare to Complemental MLC VMAT plan(CMV plan) using 20° and 340° collimator angle for nasopharyngeal carcinoma. Materials & Methods : Thirty patients treated for nasopharyngeal carcinoma with the VMAT technique were retrospectively selected. Those cases were planned by Eclipse, PO and AcurosXB Algorithm with two 6MV 360° arcs and Each arc has 273° and 350° of collimator angle. The Complemental MLC VMAT plans are based on existing treatment plans. Those plans have the same parameters of existing treatment plans but collimator angle. For dosimetric evaluation, the dose-volumetric(DV) parameters of the planning target volume (PTV) and organs at risk (OARs) were calculated for all VMAT plans. MCSv(Modulation complexity score of VMAT), MU and treatment time were also compared. In addition, Pearson's correlation analysis was performed to confirm whether there was a correlation between the difference in the MCSv and the difference in each evaluation index of the two treatment plans. Result : In the case of PTV evaluation index, the CI of PTV_67.5 was improved by 3.76% in the VMV Plan, then for OAR, the dose reduction effect of the spinal cord (-14.05%) and brain stem (-9.34%) was remarkable. In addition, the parotid glands (left parotid : -5.38%, right : -5.97%) and visual organs (left optic nerve: -4.88%, right optic nerve: -5.80%, optic chiasm : -6.12%, left lens: -6.12%, right lens: -5.26%), auditory organs (left: -11.74%, right: -12.31%) and thyroid gland (-2.02%) were also confirmed. The difference in MCSv of the two treatment plans showed a significant negative (-) correlation with the difference in CI (r=-0.55) of PTV_54 and the difference in CI (r=-0.43) of PTV_48. Spinal cord (r=0.40), brain stem (r=0.34), and both salivary glands (left: r=0.36, right: r=0.37) showed a positive (+) correlation. (For all the values, p<.05) Conclusion : Compared to the CMV plan, the VMV plan is considered to be helpful in improving the quality of the treatment plan by allowing the MLC to be modulated more efficiently

Observation of Volume Change and Subsidence at a Coal Waste Dump in Jangseong-dong, Taebaek-si, Gangwon-do by Using Digital Elevation Models and PSInSAR Technique (수치표고모델 및 PSInSAR 기법을 이용한 강원도 태백시 장성동 폐석적치장의 적치량과 침하관측)

  • Choi, Euncheol;Moon, Jihyun;Kang, Taemin;Lee, Hoonyol
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1371-1383
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    • 2022
  • In this study, the amount of coal waste dump was calculated using six Digital Elevation Models (DEMs) produced between 2006 and 2018 in Jangseong-dong, Taebaek-si, Gangwon-do, and the subsidence was observed by applying the Persistent Scatterer Interferometric SAR (PSInSAR) technique on the Sentinel-1 SAR images. As a result of depositing activities using DEMs, a total of 1,668,980 m3 of coal waste was deposited over a period of about 12 years from 2006 to 2018. The observed subsidence rate from PSInSAR was -32.3 mm/yr and -40.2 mm/yr from the ascending and descending orbits, respectively. As the thickness of the waste pile increased, the rate of subsidence increased, and the more recent the completion of the deposit, the faster the subsidence tended to occur. The subsidence rates from the ascending and descending orbits were converted to vertical and horizontal east-west components, and 22 random reference points were set to compare the subsidence rate, the waste rock thickness, and the time of depositing completion. As a result, the subsidence rate of the reference point tended to increase as the thickness of the waste became thicker, similar to the PSInSAR results in relation to the waste thickness. On the other hand, there was no clear correlation between the completion time of the deposits and the rate Of subsidence at the reference points. This is because the time of completion of the deposits at all but 5 of the 22 reference points was too biased in 2010 and the correlation analysis was meaningless. As in this study, the use of DEM and PSInSAR is expected to be an effective alternative to compensate for the lack of field data in the safety management of coal waste deposits.

Analysis of the Characteristics of Container Ports in Busan Port Using Industrial Organization Approach (산업조직론을 활용한 부산항 컨테이너 하역산업의 특성 분석)

  • Ko, Byoung-Wook;Kil, Kwang-Soo;Lee, Da-Ye
    • Journal of Korea Port Economic Association
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    • v.37 no.3
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    • pp.117-128
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    • 2021
  • In order for the users (shipping firms and shippers) and suppliers (stevedoring firms) in the container terminal industry to win-win, it is necessary to have some appropriate diverse market conditions for the industry. This study analyses the basic conditions and demand and supply characteristics of the industry and investigates the market performance of Busan container ports. First, this article analyses the basic characteristics of demand and supply. As the demand characteristics, there are five ones such as 1) exogeneity of demand, 2) function as export/import transportation and hub for transshipment, 3) increase of users' bargaining power, 4) high substituting elasticity, 5) reduction of volume growth. As the supply characteristics, there are seven ones such as 1) inelasticity of supply, 2) homogeneity of stevedoring services, 3) over-supply, 4) adoption of cutting-edge stevedoring technology, 5) scale economy and impossibility of storage, 6) labor market rigidity, 7) enhancing port's role in SCM. In addition, this study conducts the so-called structure-conduct-performance analysis. For the structure analysis, 1) lacks of scale economy in stevedoring companies, 2) high entry barrier, 3) strengthening of shipping firms' bargaining power, 4) transitory permission scheme for tariff are analyzed. For the conduct analysis, 1) price discrimination between export/import and transshipment, 2) mid-term length of terminal use contract, 3) continuous investment in equipment, 4) low level of cooperation among terminal operating firms are derived. For the performance analysis, 1) inequality in profitability, 2) reduction of export/import cost, 3) delay in adopting cutting-edge technology, 4) idle equipment are analyzed. Following this logical flow, the hypothesis that the market structure influences the market conduct is tested based on the actual dataset. As a future agenda in the conclusion, this article recommends the so-called port industrial policy.

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.

Effect of transaction characteristic factors of logistics companies on performance and long-term transaction intention (물류기업의 거래특성요인이 성과 및 장기거래의도에 미치는 영향)

  • Chung, Yeon-Joo
    • Journal of Korea Port Economic Association
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    • v.38 no.1
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    • pp.1-14
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    • 2022
  • The change in the management environment of the logistics industry in the era of global competition is becoming an era in which customers choose companies. Differentiation from competitors through the provision of products and services suitable for customers As customers' choices change depending on their superiority, companies are constantly striving to receive or retain customers' choices. Ultimately, this competitive structure can be seen as the importance of long-term relationship building. Therefore, in this study, we examined how factors related to transaction characteristics performed by logistics companies for customer satisfaction in the transaction relationship between cargo companies and shippers affect performance and long-term transaction intentions. First, we derived the factors of logistics service, cost, logistics infrastructure, and company competency, which are transaction characteristics factors of a logistics company that must be specifically realized for customer satisfaction in transactions between logistics companies. Second, we analyzed how the transaction characteristics factors of a logistics company affect the company's performance, and finally, how the company's performance factors affect long-term transaction intentions. As a result of empirical analysis, there were no statistically significant results on the relationship between transaction characteristics and performance of logistics companies, which can be attributed to the small size of the logistics companies that were the sample. In other words, logistics companies that do not have sufficient capacity to provide services at low prices have no choice but to engage in constant bleeding competition. It can be seen that it reflects the characteristics of the industry. On the other hand, the relationship between corporate performance factors and long-term transaction intention was found to have a positive relationship. The higher the level of partnership with logistics companies and visible financial performance is, the higher the transaction will be in the future, and the more the transaction volume will be gradually increased. And even if it costs a little more, it can be seen that the intention to continue trading is greatly expressed.

Alcohol Volume Consumption and Drinking Frequency among High School Students According to Social Alcohol Drinking Supplier (사회적 음주제공자에 따른 고등학생의 음주량과 음주빈도)

  • Kim, Sun-Hee;Yun, Mi-Eun;Lee, Geum-Seon
    • The Journal of the Korea Contents Association
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    • v.21 no.11
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    • pp.565-575
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    • 2021
  • The purpose of this study was to identify the amount of alcohol and drinking frequency among high school students based on social alcohol drinking supply. The data was on 161 drinkers aged between 16 and 19 from 21 high schools across the country using a questionnaire of the International Alcohol Control(IAC) Study, which was developed in 2012. Results show that the higher the number of social suppliers offering alcoholic beverages to high school students, the greater the consumption of alcohol per episode(59.433 g for one person, 113.40 g for two, and 133.56 g for three or more people). On the other hand, alcohol consumption among 'Honsul' people, a group that drinks alone without a social drinking supplier, was 167.84 grams, higher than that of groups that receive social drinking services. As a social drinking supplier for teenagers, drinking was the highest by their father (29.3 %), while friends (25.0 %) and mothers (20.7 %) were the main drinking suppliers. In particular, the provision of drinking due to father(𝛽=-.32, t=3.55, p<.01) and mother(𝛽=.22, t=2.71, p<.01) showed statistical significance as a factor in increasing the frequency of providing social drinking in adolescents. On the other hand, partner/boy or girl friend (𝛽=-.23, t=-2.73, p<.01) was a factor in reducing the frequency of alcohol provision. Friends(𝛽=.24, t=3.02, p<.01) and senior-junior schoolmates(𝛽=.16, t=2.04, p<.05) were the factors that increase the total alcohol intake of adolescents. This is due to the increase in the frequency of alcohol provision. This suggests that alcohol harm education should be expanded from students to parents, considering the role of parents as a social drinking supplier and the link between high alcohol intake among teenagers due to senior-junior friends and schoolmates.

A Study on Changes in the Safety Perception of Port Workers in accordance with the Enforcement of the Serious Disasters Act (중대재해법 시행에 따른 항만노동자의 안전인식 변화)

  • Park, Junkyu;Park, Keun-Sik
    • Journal of Korea Port Economic Association
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    • v.38 no.3
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    • pp.133-149
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    • 2022
  • The Port logistics is a pivotal industry in strengthening competitiveness for countries and companies and plays an important role in accounting for the majority of Korea's import and export volume, so its importance among Korea's industries is truly enormous. The port, which plays such an important role, is simultaneously unloaded, transferred into the dock, and stored, and it can be said that it is composed of a very complex flow. In particular, port unloading is an environment in which port unloading workers cannot escape the risk of disasters as large cargoes and cranes for container transport move, and numerous disasters are hidden and lead to serious disasters. Through literature studies on the Serious Accident Penalty Act, this study investigated how the Serious Accident Penalty Act affected port unloading workers and whether there was a change in satisfaction with safety education according to the enforcement of the Serious Accident Penalty Act. Through this study, it was found that port unloading workers were more aware of safety than managers in cognitive, attitude, and experience factors. Since the port unloading manager is not put into the unloading work, the perception of safety was analyzed to be lower than that of workers. Since managers should educate workers on safe work and be alert to safety, it seems that port unloading managers will also need to change their perception of safety. The Act on the Punishment of Severe Disasters took effect on January 27, 22, and in the early stages of the enforcement of the law, many confusing and ambiguous parts are found for those in charge of performing practical tasks on the front line until the law is settled. It seems necessary to revise the Act on the Punishment of Severe Disasters for the purpose of clear standards for the law and no safety accidents in the field to prevent confusion in work. In addition, in order to derive more meaningful research results in the future, it is expected that research on the perception of disasters by workers and managers will be continuously needed by deepening literature research to find various factors and using investigation methods such as interviews.