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Effects of Thawing Conditions in Sample Treatment on the Chemical Properties of East Siberian Ice Wedges (동시베리아 얼음쐐기 시료의 해동방법이 시료의 화학적 특성분석에 미치는 영향)

  • Subon Ko;Jinho Ahn;Alexandre Fedorov;Giehyeon Lee
    • Economic and Environmental Geology
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    • v.55 no.6
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    • pp.727-736
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    • 2022
  • Ice wedges are subsurface ice mass structures that formed mainly by freezing precipitation with airborne dust and surrounding soil particles flowed through the active layer into the cracks growing by repeating thermal contractions in the deeper permafrost layer over time. These ice masses characteristically contain high concentrations of solutes and solids. Because of their unique properties and distribution, the possibility of harnessing ice wedges as an alternative archive for reconstructing paleoclimate and paleoenvironment has been recently suggested despite limited studies. It is imperative to preserve the physicochemical properties of the ice wedge (e.g., solute concentration, mineral particles) without any potential alteration to use it as a proxy for reconstructing the paleo-information. Thawing the ice wedge samples is prerequisite for the assessment of their physicochemical properties, during which the paleo-information could be unintentionally altered by any methodological artifact. This study examined the effect of thawing conditions and procedures on the physicochemical properties of solutes and solid particles in ice wedge samples collected from Cyuie, East Siberia. Four different thawing conditions with varying temperatures (4 and 23℃) and oxygen exposures (oxic and anoxic) for the ice wedge sample treatment were examined. Ice wedge samples thawed at 4℃ under anoxic conditions, wherein biological activity and oxidation were kept to a minimum, were set as the standard thawing conditions to which the effects of temperature and oxygen were compared. The results indicate that temperature and oxygen exposure have negligible effects on the physicochemical characteristics of the solid particles. However, the chemical features of the solution (e.g., pH, electric conductivity, alkalinity, and concentration of major cations and trace elements) at 4℃ under oxic conditions were considerably altered, compared to those measured under the standard thawing conditions. This study shows that the thawing condition of ice wedge samples can affect their chemical features and thereby the geochemical information therein for the reconstruction of the paleoclimate and/or paleoenvironment.

A Study on the Pattern and Promotion of Landscape Architects Participation in Urban Regeneration Projects- Focusing on the Urban Regeneration New Deal Project (2017-2019) - (도시재생사업에서 조경의 참여 양상과 증진 모색 - 도시재생 뉴딜 선정사업(2017-2019)을 중심으로 -)

  • Lee, Jeong-Hee;Yun, Young-Jo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.6
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    • pp.96-109
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    • 2022
  • This study aims to identify the role and the use of landscape architects as a core strategy in urban regeneration projects by project type. This study attempted to find ways to promote landscape architects' participation patterns and characteristics in promoting urban regeneration and revitalization plans. Among the New Deal projects, from 2017 to 2019, when the urban regeneration projects were promoted, a total of 822 projects with terms such as park, garden, landscaping, rest space, forest, greening, planting, and flowers were included, In this study, an integrated approach was applied, considering the status of landscape architects participation, a literature survey by project entity, analysis of prior research, revitalization plan reports, and interviews by project entity, and aspects and characteristics of landscape architects participation according to project type. The results were classified. In the urban regeneration projects, the landscape characteristics were analyzed in terms of hardware or software participation methods according to the project type, and the participation patterns and promotion measures of landscape architecture and ways to promote them identified in the course of the project are as follows. First, the role and participation pattern of landscape architects in urban regeneration projects differed depending on the type of project. As the prerequisites for each type of project, the subject of the project, the direction, the differentiation of the regeneration strategy for each project, and the level of participation of residents interacted in a complex way. The participation of landscape architects has changed and expanded its meaning and role. Second, the change and value of the expanded the participation method of landscape architects in the urban regeneration project and appeared as a multi-purpose and complex role in the process of a project, indicating that the value of landscape in the classical sense is changing and its substantive aspect depends on the type of project. Third, this study confirmed the importance of recognizing the role and value of 'landscape architecture' as a strategic and practical means of regeneration that can be utilized. Therefore, in order to promote the participation of landscape architects, diversification is required through changes in participation methods according to urban regeneration strategies for each project, rather than participation focused on hardware projects, such as park creation in terms of form and place. In addition, it was confirmed that the participation of landscape architects, which play an important role in fostering a sense of community among residents as an experience and activity program, should be further activated in terms of the process of the ideal way of existence. This study is meaningful in that it substantially grasps that the role of landscape architects is expanding as the subject of urban regeneration projects, and presents the direction for its promotion. Participation and research should be continued.

An Installation and Model Assessment of the UM, U.K. Earth System Model, in a Linux Cluster (U.K. 지구시스템모델 UM의 리눅스 클러스터 설치와 성능 평가)

  • Daeok Youn;Hyunggyu Song;Sungsu Park
    • Journal of the Korean earth science society
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    • v.43 no.6
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    • pp.691-711
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    • 2022
  • The state-of-the-art Earth system model as a virtual Earth is required for studies of current and future climate change or climate crises. This complex numerical model can account for almost all human activities and natural phenomena affecting the atmosphere of Earth. The Unified Model (UM) from the United Kingdom Meteorological Office (UK Met Office) is among the best Earth system models as a scientific tool for studying the atmosphere. However, owing to the expansive numerical integration cost and substantial output size required to maintain the UM, individual research groups have had to rely only on supercomputers. The limitations of computer resources, especially the computer environment being blocked from outside network connections, reduce the efficiency and effectiveness of conducting research using the model, as well as improving the component codes. Therefore, this study has presented detailed guidance for installing a new version of the UM on high-performance parallel computers (Linux clusters) owned by individual researchers, which would help researchers to easily work with the UM. The numerical integration performance of the UM on Linux clusters was also evaluated for two different model resolutions, namely N96L85 (1.875° ×1.25° with 85 vertical levels up to 85 km) and N48L70 (3.75° ×2.5° with 70 vertical levels up to 80 km). The one-month integration times using 256 cores for the AMIP and CMIP simulations of N96L85 resolution were 169 and 205 min, respectively. The one-month integration time for an N48L70 AMIP run using 252 cores was 33 min. Simulated results on 2-m surface temperature and precipitation intensity were compared with ERA5 re-analysis data. The spatial distributions of the simulated results were qualitatively compared to those of ERA5 in terms of spatial distribution, despite the quantitative differences caused by different resolutions and atmosphere-ocean coupling. In conclusion, this study has confirmed that UM can be successfully installed and used in high-performance Linux clusters.

Service Philosophy as Wisdom for Human Society Development (인류사회 발전 지혜로서의 서비스철학)

  • Hyunsoo Kim
    • Journal of Service Research and Studies
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    • v.12 no.4
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    • pp.1-18
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    • 2022
  • This study was conducted to prove that the service philosophy is the development principle of human society in the service age. From ancient times to the present, the service philosophy was tried to show the wisdom of the development of human society in all earth spaces including the East and the West. In addition, it tried to prove that the service philosophy was at the center of the development wisdom of many countries and individuals who flickered on all space on earth and all human time. The study showed that the differences between countries were in software rather than hardware. Furthermore, it was analyzed that countries with a service philosophy embedded in the center of software such as spirit and culture made a great contribution to human society. The cases of Greece and Rome, the Republic of Venice, the Republic of the Netherlands, followed by the United States and modern Korea prove this, and the Soviet Union can be seen to disprove it. The former was a society in which state-run software was strong, and the latter was a society in which hardware was strong. There is a big difference between the case of the state, which citizens have autonomously organized and operated, and the case of the upper-level state-led operation. Since the leadership of the upper classes is not based on the service philosophy, the accumulated software power is weak, so it can be said that the accumulation of wisdom in human society is weak. Therefore, while the essence of human society so far has been a society of self-centered animal ecosystems led by selfishness, the human society in the service age from now on can be said to be a society of plant ecosystems where mutual respect and self-centeredness coexist. Just as the society centered on the service philosophy in the past human society prospered and left a greater legacy to mankind, it is suggested that the human society in the future service era should be a human society of a plant ecosystem centered on the service philosophy. Further in-depth studies related to this are needed in the future.

Empirical Study of Biogas Purification Equipment (바이오가스 정제 설비의 실증 연구)

  • Hwan Cheol Lee;Jae-Heon Lee
    • Plant Journal
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    • v.18 no.4
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    • pp.58-65
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    • 2023
  • In this study, to increase the methane content of biogas supplied from Nanji Water Regeneration Center and to purify impurities, a three-stage membrane purification process was designed and installed to demonstrate operation. The methane concentration of biomethane produced in the 2 Nm3/h purification process was set to three cases: 95%, 96.5%, and 98%, and the membrane area ratio of the membrane was 1:1, 1:2, 1:1:1, The optimum conditions for the membrane area of the separator were derived by changing to five of 1:2:1 and 1:2:2. 3 stage separation membrane process of 30 Nm3/h was installed to reflect the optimum condition of 2 Nm3/h, and biomethane production of 98% or more of methane concentration was demonstrated. As a result of the operation of the 2 Nm3/h refining device, the methane recovery rate at the 98% methane concentration was 95.6% when the membrane area ratio was 1:1 as the result of the two-stage operation of the separator, and the recovery rate of methane at 1:2 was increased to 96.8%. The methane recovery rate of the membrane three-stage operation was highest at 96.8% when the membrane area ratio was operated at 1:2:1. The carbon dioxide removal rate was 16.4 to 96.4% and the 2:2 to 95.7% film area ratio in the two-step process. In the three-step process, the film area ratio was 1:2:1 to 95.4%, and the two-step process showed higher results than the three-step process. In the 30 Nm3/h scale biogas purification demonstration operation, the methane concentration after purification was 98%, the recovery rate of methane was 97.1%, the removal rate of carbon dioxide was 95.7%, and hydrogen sulfide, the cause of corrosion, was not detected, and the membrane area ratio was 1:2:1 demonstration operation, biomethane production with a methane concentration of 98% or higher was possible.

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Levels of Physicians' Self-assessment of Life Satisfaction and Associated Factors (임상의사의 삶의 만족도 자가평가 수준과 관련 요인)

  • Jong Sun Ok;Hyeongsu Kim
    • Journal of agricultural medicine and community health
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    • v.48 no.1
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    • pp.28-40
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    • 2023
  • Objectives: This study aimed to identify the level of self-assessment of life satisfaction and various factors related to the life satisfaction of Korean physicians. Methods: This study is a secondary data analysis using the 2016 Korean physician survey Korean Physician Survey(KPS) data collected by the Research Institute for Healthcare Policy of the Korean Medical Association. The member database(DB) of the Korean Medical Association was used for sampling and the target population was formed and surveyed by using stratified quota sampling. A questionnaire was sent by E-mail as an online survey method and was conducted for a total of 7 weeks from November 21, 2016 to January 8, 2017. The final number of respondents was 8,564 (response rate 13.8%). In this study, a total of 7,228 physicians, excluding residents and public health doctors who are currently treating patients directly, were studied. Factors affecting the life satisfaction of physicians were analyzed using ordinal logistic regression analysis. Results: The physical factors positively related to the life satisfaction of physicians were those who were in their 60s, female, and thought they had good health status. As for psychological factors, stress was low. As for economic factors, satisfaction with income was high. As for social factors, the physicians lived with their families and were satisfied with the time they could spend with them. Also, the physicians were satisfied with the social respect they received as a doctors. Conclusions: Based on the results of this study, it is thought that a multifaceted approach is needed to increase the life satisfaction of physicians.

Effects of Magnetite(Fe3O4) as Electrical Conductor of Direct Interspecies Electron Transfer on Methane Yield of Food Wastewater (종간직접전자전달 전도체로서 Magnetite(Fe3O4)가 음폐수의 메탄생산에 미치는 영향)

  • Jun-Hyeong Lee;Tae-Bong Kim;Chang-Hyun Kim;Young-Man Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.1
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    • pp.15-26
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    • 2023
  • Methane production by anaerobic digestion occurs through interspecies electron transfer (DIET), a synthetic metabolism between acetic and methanate bacteria through hydrolysis and acid production steps. In this study, to improve methane yield, the effect of addition of magnetite (Fe3O4), a conductor promoting DIET on methane production in food wastewater was investigated, and the effect on methane yield was assessed by methane potential (Bu) and maximum methane production rate [Rm(t0)] by the operation of batch type anaerobic reactor adding Fe3O4. The Bu and Rm(t0) of food wastewater without Fe3O4 were 0.496 Nm3/kg-VSadded and 38.24 mL/day, respectively. The t0 which reached to Rm appeared at 21.06 days during the operation of the anaerobic reactor. The Bu of food wastewater with Fe3O4 was 0.502, 0.498, 0.512, 0.510, 0.518, 0.523, 0.524, 0.540, and 0.549 Nm3/kg-VSadded in the treatment of 5, 10, 15, 20, 25, 30, 40, 70, and 100mM-Fe3O4, respectively, and the Bu significantly increased to 36.95% with the addition of magnetite in the addition of 15mM-Fe3O4. And, the addition of Fe3O4 shortened the duration to reach Rm from 21.06 days to the maximum of 14.67 days by the addition of Fe3O4. Therefore, the methane yield and production rate of food wastewater significantly improved with the addition of Fe3O4.

Early Effect of Environment-friendly Harvesting on the Dynamics of Organic Matter in a Japanese Larch (Larix leptolepis) Forest in Central Korea (중부지역 일본잎갈나무림의 친환경벌채가 산림 내 유기물 변화에 미치는 초기 영향)

  • Wang, Rui Jia;Kim, Dong Yeob
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.473-481
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    • 2022
  • Environment-friendly harvesting is practiced to maintain ecosystem, landscape, and forest protection functions. The present study was conducted at Simgok-ri, Sinbuk-myeon, Pocheon, Gyeonngi-do, where a 41-50-year-old Japanese larch forest was harvested in an environment-friendly manner from 2017 to 2019. The dynamics of organic matter in this forest were investigated at three years after the harvest. Specifically, organic matter content was measured on the forest floor and in overstory biomass, litterfall, and soil up to 30 cm in depth from June 2020 to January 2021. Owing to the harvest, the amount of overstory biomass of the Japanese larch stands decreased from 142.22 to 44.20 t ha-1. On the forest floor, the amount of organic matter was 32.87 t ha-1 in the control plots and 23.34 t ha-1 in the harvest plots. Annual litterfall was 4.43 t ha-1 yr-1 in the control plots and 1.16 t ha-1 yr-1 in the harvest plots. Soil bulk density in the B horizon was 0.97 g cm-3 in the control plots and 1.06 g cm-3 i n the harvest plots. Soil organic matter content was 11.5% in the control plots and 12.8% in the harvest plots. The total amount of soil organic matter did not differ significantly between the control plots (245.21 t ha-1) and harvest plots (263.92 t ha-1), although the amount of soil organic matter tended to be higher in the harvest plots. The total amount of organic matter in the forest was estimated to be 406.48 t ha-1 in the control plots and 338.21 t ha-1 in the harvest plots. In the harvest plots, the ratio of aboveground organic matter decreased to 13.1% and soil organic matter increased to 78.0%, indicating that the distribution of organic matter changed significantly in these plots. Overall, the carbon accumulated in aboveground biomass was substantially reduced by environment-friendly harvesting, whereas the soil carbon level increased, which played a role in mitigating the reduction of system carbon in the forest. These results highlight one possible resolution for forest management in terms of coping with climate change. However, given that only three years of environment-friendly harvesting data were analyzed, further research on the dynamics of organic matter and tree growth is needed.

Comparison of Habitat Quality by the Type of Nature Parks (자연공원 종류별 서식지질 비교)

  • Jung-Eun Jang;Min-Tai Kim;Hye-Yeon Kwon;Hae-Seon Shin;Byeong-Hyeok Yu;Sang-Cheol Lee;Song-Hyun Choi
    • Korean Journal of Environment and Ecology
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    • v.36 no.6
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    • pp.553-565
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    • 2022
  • Awareness of the ecological value and importance of protected areas has increased as climate change accelerates, and there is a need for research on ecosystem services provided by nature. The natural park, which is a representative protected area in Korea, has a system of national parks, provincial parks, and county parks. National parks are managed systematically by the Korea National Park Service, but local governments manage provincial parks and county parks. There may be the same hierarchical differences in naturalness (habitat quality) depending on the hierarchy of the natural parks, but it has not been verified. To identify differences, we examined 22 mountain-type natural parks using habitat quality using the INVEST model developed by Stanford University. The analysis of the habitat quality, regardless of the type and area of the natural park, showed that it was higher in the order of Taebaeksan National Park (0.89), Juwangsan National Park (0.87), Woongseokbong County Park (0.86), and Gayasan National Park (0.85). The larger the area, the higher the value of habitat quality. A comparison of natural parks with similar areas showed that the habitat quality of national parks was higher than that of provincial parks and parks. On the other hand, the average habitat quality of county parks was 0.83±0.02, which was 0.05 higher than that of provincial parks at 0.78±0.03. Furthermore, the higher the proportion of forest areas within the natural park, the higher the habitat quality. The results confirmed that the naturalness of natural parks was independent of their hierarchy and that there are differences in naturalness depending on land use, land coverage, and park management.

The Effect of Untact Shopping Customer Experience on Continuous Use Intention through Expectation-Confirmation Model (언택트 쇼핑의 고객경험이 기대일치 모델을 통해 지속이용의도에 미치는 영향)

  • Hong, Suji;Han, Sang-Lin
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.227-245
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    • 2023
  • As offline company and online·mobile startups meet in an untact shopping environment, competition among companies in untact shopping is increasing. In this situation, companies need their own clear strategy to create customer value. In particular, it is very important to focus on 'customer experience' to establish such a strategy in an untact shopping environment. Customer experience refers to all processes in which consumers meet and experience a company or brand at a touch point. In this processes consumers decide whether to continue to use the company and brand. In this situation, it is thought that it will be meaningful for research to examine the customer experience of untact shopping. Therefore, this study aimed to examine the customer experience of untact shopping, which is used by all generations after COVID-19, through experience quality, and to examine the impact on the expectation-confirmation Model of untact shopping. The results of this study are as follows. First, as a result of examining whether interaction quality, information quality, and outcome quality affect expectation-confirmation it was found that all qualities except interaction quality affect expectation matching. Second, as a result of examining whether interaction quality, information quality, and outcome quality affect perceived usefulness, it was found that all qualities except interaction quality had an effect. Next, as a result of applying the expectation confirmation model to the untact shopping environment and examining whether the expectation confirmation has an effect on use satisfaction, it was found that there was a positive effect. As a result of examining whether perceived usefulness affects use satisfaction, it was found to have a positive effect. As a result of examining whether perceived usefulness affects expectation confirmation, it was found that there is a positive effect. Finally, as a result of examining whether perceived usefulness affects the intention to continue using untact shopping, it was found to be positive. Next, as a result of examining the effect of use satisfaction on trust, it was found that there was a positive effect. Finally, as a result of investigating whether trust has an effect on the intention to continue using, it was found that there is a positive effect. Looking at the important results especially, information quality was found to have the greatest influence.