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Initial Analysis of the Underground Air Among Jeju Lava Forest(Sumgol) and its Healing Effect on the Human Body (제주 현무암 '숲' 지하 공기(숨골: Sumgol)의 분석과 인체에 미치는 치유 효과)

  • Sin, SBangsik;Kim, Hyek Nyeon;Lee, Deok Hee;Kim, Tae Seung;Kim, Yong Hwan;Kang, Chang Hee;Song, Kyu Jin;Lee, Hyung H.
    • Journal of Naturopathy
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    • v.11 no.1
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    • pp.18-30
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    • 2022
  • Background: It was to develop an air purification system (APS) using an underground air purification layer to verify the effect of basalt forest's underground air (sumgol) on a volcanic Jeju. Finally, it is necessary to analyze these purified air components and their usefulness to the human body in an air experience center. Purpose: It was to collect basalt forest air, analyze its composition, and explore its effect on the human body. Methods: We APS devices installed at four points in the Papaville area of Jeju. The air discharged from the APS was collected and analyzed the recycling components. An installed experience room filled with negative ions is about 5,000 ions/m3. After allowing the participants to stay for 60 to 120 minutes, we investigated the state of blood vessels. Results: In the analysis of the underground air, the O2 concentration was 21.18%, which was higher than the average oxygen concentration of 20.94% in the atmosphere. However, Formaldehyde was not detected, and the CO2 was 419 ppm, which was lower than that of indoor air. The PM2.5 concentration was less than 24 ㎍/m3 and detected anions over 5.000 /m3. The experiencer's vascular states improved, and the increase in pulse rate and stress relief were high. Conclusions: The valuable ingredients identified by analyzing the air were precious for natural healing. The experience results showed that it effectively improved the pulse rate, blood vessels, and stress. These conditions may be highly beneficial as a new area for expanding the basalt lava forest in the Jeju area into the natural healing and wellness industry.

A basic study on explosion pressure of hydrogen tank for hydrogen fueled vehicles in road tunnels (도로터널에서 수소 연료차 수소탱크 폭발시 폭발압력에 대한 기초적 연구)

  • Ryu, Ji-Oh;Ahn, Sang-Ho;Lee, Hu-Yeong
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.6
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    • pp.517-534
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    • 2021
  • Hydrogen fuel is emerging as an new energy source to replace fossil fuels in that it can solve environmental pollution problems and reduce energy imbalance and cost. Since hydrogen is eco-friendly but highly explosive, there is a high concern about fire and explosion accidents of hydrogen fueled vehicles. In particular, in semi-enclosed spaces such as tunnels, the risk is predicted to increase. Therefore, this study was conducted on the applicability of the equivalent TNT model and the numerical analysis method to evaluate the hydrogen explosion pressure in the tunnel. In comparison and review of the explosion pressure of 6 equivalent TNT models and Weyandt's experimental results, the Henrych equation was found to be the closest with a deviation of 13.6%. As a result of examining the effect of hydrogen tank capacity (52, 72, 156 L) and tunnel cross-section (40.5, 54, 72, 95 m2) on the explosion pressure using numerical analysis, the explosion pressure wave in the tunnel initially it propagates in a hemispherical shape as in open space. Furthermore, when it passes the certain distance it is transformed a plane wave and propagates at a very gradual decay rate. The Henrych equation agrees well with the numerical analysis results in the section where the explosion pressure is rapidly decreasing, but it is significantly underestimated after the explosion pressure wave is transformed into a plane wave. In case of same hydrogen tank capacity, an explosion pressure decreases as the tunnel cross-sectional area increases, and in case of the same cross-sectional area, the explosion pressure increases by about 2.5 times if the hydrogen tank capacity increases from 52 L to 156 L. As a result of the evaluation of the limiting distance affecting the human body, when a 52 L hydrogen tank explodes, the limiting distance to death was estimated to be about 3 m, and the limiting distance to serious injury was estimated to be 28.5~35.8 m.

Korean Family Business Research : A Review and Agenda for Future Research (우리나라 가족기업의 연구동향과 과제)

  • Nam, YoungHo
    • Korean small business review
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    • v.42 no.2
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    • pp.69-92
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    • 2020
  • This study is aimed at the growth and development of family businesses that greatly contribute to Korea's economic development, but the specific research purpose is to firstly examine the research trends and current status of Korean family businesses and compare them with those of developed countries such as the United States. Second, I would like to look at the future research for revitalizing Korean family business research. In addition, we intend to contribute to increasing the interest in this field and the number of researchers involved. The research target of this paper is 212 papers published in professional academic journals for 13 years from 2006 to 2018 when family businesses began to be fully researched in Korea, 112 master's and doctoral dissertations (graduate schools), and 324 totals. As a result of empirical analysis, the number of published papers is increasing more than the initial ones, but it has been on the decline recently. In addition, 57.5% of the journals are papers that do not have specific definitions or simply list the claims of several scholars by analyzing content. Thesis was 33.9%. As for the type of research, qualitative research, which is a conceptual research, is a small number, and empirical research occupies most of the research topics. Research topics and academic dissertations also have a large proportion of management, management strategy, succession, financial accounting, and business performance. In other words, it can be said that the research on family business in Korea corresponds to the early childhood of the United States. First of all, in the future, we need to put more effort into increasing the qualitative research, starting with the definition of a family business, which is an essential problem, in addition to the theory building of family business. Second, as an analysis level of research, we should make family an important level of analysis for existing individuals, groups, and organizations. Third, the research subject and research area should be expanded. It is desperately necessary to study large companies including chaebols, mainly from small and medium-sized companies, which are the existing research areas of family business. In addition, it is considered that it is necessary to appropriately introduce various theories suitable for the interdisciplinary study, which is the characteristic of the family business, for example, theories of family science, psychology, and sociology. Fourth, it should build the research infrastructure.

Case Study of Regional Cultural Contents Development Using Peacock Fan Intangible Cultural Asset (충남 무형문화재 공작부채를 활용한 지역문화 콘텐츠 개발 사례 연구)

  • Kim, Dae-Gi;Son, Ji-Yeong;Baek, U-Young
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.5
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    • pp.87-102
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    • 2020
  • The purpose of this study was to develop regional dance contents in order to receive attention from the region and re-illuminate the peacock fan, the intangible cultural property of Seocheon, Chungnam, which has been preserved in history and has been preserved in the face of rapid urbanization and modernization. The representative four series are composed of one-person dance, two-person dance, military dance, and creative dance. The titles of each piece are basic dance , male and female love dance , military dance , and finally Korean creative dance . The commonality of the four series is the traditional dance using peacock fan, and each dance showed unique emotion and atmosphere through different themes and music, costumes, and stages. It was found that the development of regional dance contents re-created reflecting the characteristics of regional cultural heritage should create an environment that can be steadily revitalized through modernization. Through this study, it was found that the intangible cultural properties, which are our traditional cultural resources, have unlimited potential to contribute to enhancing regional and national competitiveness along with the growth potential of regional differentiation. Through such research, if existing cultural resources are preserved for globalization and produced as contents that can be easily accessed by the public, various contents besides regional dance using regional unique culture can be developed and utilized.

The Use of Transmedia in Current Affairs Radio Shows Focusing on 'That Honey Show' of Kim Hyun-Jung's News Show(CBS) (라디오 시사프로그램의 트랜스미디어 활용 연구 - CBS <김현정의 뉴스쇼-댓꿀쇼>를 중심으로 -)

  • Shin, Jung-Ah;Han, Hee-Jeong
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.6
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    • pp.35-54
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    • 2021
  • This study examines the characteristics of CBS's Kim Hyun-Jung's News Show(hearafter News Show) and the change to transmedia. The distinguishing characteristics of News Show compared to radio-based current affairs programs are as follows. First, despite its time limit, it adopts the form of investigative reports or investigative documentaries to uncover the truth of the events through 'Detective Son Su-Ho', etc. Second, News show's interviews have avoided biased stance in the reporting of minority issues by interviewing the affected parties anonymously including people involved in incidents and accidents, bereaved families, and other victims. News Show has been producing a transmedia content called 'That Honey Show' (a show that reads comments as fun as honey) since November 2018. 'That Honey Show' is broadcast in real time on YouTube right after the News Show radio broadcast ends. As a form of spin-off content, 'That Honey Show' breaks down the boundaries among staff, MCs, and guests, as well as shifting roles by using 'vice characters'. The female host, Kim conducts interviews with the main characters related to various issues and extends the fixed identity of current affairs shows to the everyday politics and cultural realms. Thus she draws active participation and responses audience. This paper analyzes two representative broadcast cases of 'That Honey Show'-first, the case of resistance and activity of the BTS fandom ARMY in the US presidential election, and, second, the case of reporting on the Nth room incident. This analysis considers the critical participation of digital citizens and the effect of fostering a sense of community in the current affairs show in the transmedia era.

Rare Earth Elements (REE)-bearing Coal Deposits: Potential of Coal Beds as an Unconventional REE Source (함희토류 탄층: 비전통적 희토류 광체로서의 가능성에 대한 고찰)

  • Choi, Woohyun;Park, Changyun
    • Economic and Environmental Geology
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    • v.55 no.3
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    • pp.241-259
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    • 2022
  • In general, the REE were produced by mining conventional deposits, such as the carbonatite or the clay-hosted REE deposits. However, because of the recent demand increase for REE in modern industries, unconventional REE deposits emerged as a necessary research topic. Among the unconventional REE recovery methods, the REE-bearing coal deposits are recently receiving attentions. R-types generally have detrital originations from the bauxite deposits, and show LREE enriched REE patterns. Tuffaceous-types are formed by syngenetic volcanic activities and following input of volcanic ash into the basin. This type shows specific occurrence of the detrital volcanic ash-driven minerals and the authigenic phosphorous minerals focused at narrow horizon between coal seams and tonstein layers. REE patterns of tuffaceous-types show flat shape in general. Hydrothermal-types can be formed by epigenetic inflow of REE originated from granitic intrusions. Occurrence of the authigenic halogen-bearing phosphorous minerals and the water-bearing minerals are the specific characteristics of this type. They generally show HREE enriched REE patterns. Each type of REE-bearing coal deposits may occur by independent genesis, but most of REE-bearing coal deposits with high REE concentrations have multiple genesis. For the case of the US, the rare earth oxides (REO) with high purity has been produced from REE-bearing coals and their byproducts in pilot plants from 2018. Their goal is to supply about 7% of national REE demand. For the coal deposits in Korea, lignite layers found in Gyungju-Yeongil coal fields shows coexistence of tuff layers and coal seams. They are also based in Tertiary basins, and low affection from compaction and coalification might resulted into high-REE tuffaceous-type coal deposits. Thus, detailed geologic researches and explorations for domestic coal deposits are required.

A Basis Study on the Optimal Design of the Integrated PM/NOx Reduction Device (일체형 PM/NOx 동시저감장치의 최적 설계에 대한 기초 연구)

  • Choe, Su-Jeong;Pham, Van Chien;Lee, Won-Ju;Kim, Jun-Soo;Kim, Jeong-Kuk;Park, Hoyong;Lim, In Gweon;Choi, Jae-Hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.1092-1099
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    • 2022
  • Research on exhaust aftertreatment devices to reduce air pollutants and greenhouse gas emissions is being actively conducted. However, in the case of the particulate matters/nitrogen oxides (PM/NOx) simultaneous reduction device for ships, the problem of back pressure on the diesel engine and replacement of the filter carrier is occurring. In this study, for the optimal design of the integrated device that can simultaneously reduce PM/NOx, an appropriate standard was presented by studying the flow inside the device and change in back pressure through the inlet/outlet pressure. Ansys Fluent was used to apply porous media conditions to a diesel particulate filter (DPF) and selective catalytic reduction (SCR) by setting porosity to 30%, 40%, 50%, 60%, and 70%. In addition, the ef ect on back pressure was analyzed by applying the inlet velocity according to the engine load to 7.4 m/s, 10.3 m/s, 13.1 m/s, and 26.2 m/s as boundary conditions. As a result of a computational fluid dynamics analysis, the rate of change for back pressure by changing the inlet velocity was greater than when inlet temperature was changed, and the maximum rate of change was 27.4 mbar. This was evaluated as a suitable device for ships of 1800kW because the back pressure in all boundary conditions did not exceed the classification standard of 68mbar.

The Induction of ROS-dependent Autophagy by Particulate Matter 2.5 and Hydrogen Peroxide in Human Lung Epithelial A549 Cells (미세먼지와 산화적 스트레스에 의한 인간 폐 상피 A549 세포에의 ROS 의존적 자가포식 유도)

  • Park, Beom Su;Kim, Da Hye;Hwangbo, Hyun;Lee, Hyesook;Hong, Su Hyun;Cheong, Jaehun;Choi, Yung Hyun
    • Journal of Life Science
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    • v.32 no.4
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    • pp.310-317
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    • 2022
  • Recently, interest in the harmful factors of particulate matter (PM), a major component of air pollution, has been increasing. In particular, PM2.5 with a diameter of less than 2.5 ㎛ is well known to induce oxidative stress accompanied by autophagy in human lung epithelial cells. However, studies on whether PM2.5 increases autophagy under oxidative stress and whether this process is reactive oxygen species (ROS)-dependent are insufficient. Therefore, in this study, we investigated whether PM2.5 promotes autophagy through the generation of ROS in human alveolar epithelial A594 cells. According to our results, cells co-treated with PM2.5 and hydrogen peroxide (H2O2) showed a lower cell viability than cells treated with each alone, which was associated with increased total and mitochondrial ROS production. The co-treatment of PM2.5 and H2O2 also increased autophagy induction, which was confirmed through Cyto-ID staining, and the expression of autophagy biomarker proteins increased. However, when ROS generation was artificially blocked by N-acetyl-L-cysteine pretreatment, the reduction in cell viability and induction of autophagy by PM2.5 and H2O2 co-treatment were markedly attenuated. Therefore, the present results suggest that PM2.5-induced ROS generation may play a critical role in autophagy induction in A549 cells.

Performance Optimization of Numerical Ocean Modeling on Cloud Systems (클라우드 시스템에서 해양수치모델 성능 최적화)

  • JUNG, KWANGWOOG;CHO, YANG-KI;TAK, YONG-JIN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.27 no.3
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    • pp.127-143
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    • 2022
  • Recently, many attempts to run numerical ocean models in cloud computing environments have been tried actively. A cloud computing environment can be an effective means to implement numerical ocean models requiring a large-scale resource or quickly preparing modeling environment for global or large-scale grids. Many commercial and private cloud computing systems provide technologies such as virtualization, high-performance CPUs and instances, ether-net based high-performance-networking, and remote direct memory access for High Performance Computing (HPC). These new features facilitate ocean modeling experimentation on commercial cloud computing systems. Many scientists and engineers expect cloud computing to become mainstream in the near future. Analysis of the performance and features of commercial cloud services for numerical modeling is essential in order to select appropriate systems as this can help to minimize execution time and the amount of resources utilized. The effect of cache memory is large in the processing structure of the ocean numerical model, which processes input/output of data in a multidimensional array structure, and the speed of the network is important due to the communication characteristics through which a large amount of data moves. In this study, the performance of the Regional Ocean Modeling System (ROMS), the High Performance Linpack (HPL) benchmarking software package, and STREAM, the memory benchmark were evaluated and compared on commercial cloud systems to provide information for the transition of other ocean models into cloud computing. Through analysis of actual performance data and configuration settings obtained from virtualization-based commercial clouds, we evaluated the efficiency of the computer resources for the various model grid sizes in the virtualization-based cloud systems. We found that cache hierarchy and capacity are crucial in the performance of ROMS using huge memory. The memory latency time is also important in the performance. Increasing the number of cores to reduce the running time for numerical modeling is more effective with large grid sizes than with small grid sizes. Our analysis results will be helpful as a reference for constructing the best computing system in the cloud to minimize time and cost for numerical ocean modeling.

Estimation of Monthly Dissolved Inorganic Carbon Inventory in the Southeastern Yellow Sea (황해 남동부 해역의 월별 용존무기탄소 재고 추정)

  • KIM, SO-YUN;LEE, TONGSUP
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.27 no.4
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    • pp.194-210
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    • 2022
  • The monthly inventory of dissolved inorganic carbon (CT) and its fluxes were simulated using a box-model for the southeastern Yellow Sea, bordering the northern East China Sea. The monthly CT data was constructed by combining the observed data representing four seasons with the data adopted from the recent publications. A 2-box-model of the surface and deep layers was used, assuming that the annual CT inventory was at the steady state and its fluctuations due to the advection in the surface box were negligible. Results of the simulation point out that the monthly CT inventory variation between the surface and deep box was driven primarily by the mixing flux due to the variation of the mixed layer depth, on the scale of -40~35 mol C m-2 month-1. The air to sea CO2 flux was about 2 mol C m-2 yr-1 and was lower than 1/100 of the mixing flux. The biological pump flux estimated magnitude, in the range of 4-5 mol C m-2 yr-1, is about half the in situ measurement value reported. The CT inventory of the water column was maximum in April, when mixing by cooling ceases, and decreases slightly throughout the stratified period. Therefore, the total CT inventory is larger in the stratified period than that of the mixing period. In order to maintain a steady state, 18 mol C m-2 yr-1 (= 216 g C m-2 yr-1), the difference between the maximum and minimum monthly CT inventory, should be transported out to the East China Sea. Extrapolating this flux over the entire southern Yellow Sea boundary yields 4 × 109 g C yr-1. Conceptually this flux is equivalent to the proposed continental shelf pump. Since this flux must go through the vast shelf area of the East China Sea before it joins the open Pacific waters the actual contribution as a continental shelf pump would be significantly lower than reported value. Although errors accompanied the simple box model simulation imposed by the paucity of data and assumptions are considerably large, nevertheless it was possible to constrain the relative contribution among the major fluxes and their range that caused the CT inventory variations, and was able to suggest recommendations for the future studies.