• Title/Summary/Keyword: Natural Science

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Korean and Worldwide Research Trends on Rare Plant and Endemic Plant in Korea (한국의 희귀 및 특산식물에 대한 국내·외 연구동향)

  • Chae, Hyun-Hee;Kim, Young-Chul;Son, Sung-Won
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.257-276
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    • 2022
  • Studies on rare and endemic plant conservation should be performed nationally to conserve plant diversity. Studies targeting a specific taxon have been reported based on the necessity of conserving plant diversity. From this point of view, there is an increasing necessity to compare and evaluate the studies for conservation. Moreover, it is necessary to analyze and review the direction for study subjects and items required for effective conservation of rare and endemic plants in Korea, based on the analysis results of collected data. We analyzed trends of studies on rare and endemic plants worldwide. In particular, we collected and analyzed the study trend in Korea. Study fields of the rare and endemic plants were divided into six classifications, of which the conservation ecology classification was sub-divided into the species traits, population study, and biological interaction. We have collected conservation ecology studies showing significant differences in regions and countries. They have been actively conducted in Europe and North America by region and in Japan and the United States by country. On the contrary, studies on basic ecology accounted for the most, followed by conservation genetics and restoration ecology in Korea. It was revealed that the portion of conservation ecology conducted in Korea was lower than that of the world. Moreover, studies mainly focused on a specific taxon of rare and endemic plants, such as endangered plants designated by the Korean Ministry of Environment. Particularly in Korea, conservation genetics and restoration ecology studies accounted for high percentages. Considering the worldwide study trends, particularly those in Europe and North America that lead the study of conservation ecology, we suggest approaches to increase the percentages of conservation ecology, including securing the information on species traits, population structure and population dynamics, and interaction between animals and plants are necessary for effective conservation of rare and endemic plants in Korea.

Anti-inflammatory and Cytotoxic Screening Evaluation of Macroalgae Resources (국내 해조류 자원의 항염증 및 세포독성 스크리닝 평가)

  • Kim, C.W.;Chang, K.J.;Kim, Y.B.;Kim, D.H.;Chae, C.J.;Choi, H.G.;Koo, H.J.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.22 no.2
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    • pp.69-79
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    • 2020
  • In this study, the anti-inflammatory and cytotoxic effects of hot-water extracts from 10 kinds of macroalgae in Korea were investigated. It was selected materials in consideration of biological activity and industrial potential as follows: Caulerpa okamurae; Codium fragile; Ulva australis; Ishige foliacea; Saccharina japonica; Sargassum horneri; Undaria pinnatifida; Gloiopeltis tenax; Gracilaria verrucosa; Porphyra tenera. Results showed that S. japonica and G. tenax significantly decreased NO productionn in LPS-stimulated Raw 264.7 cells at concentrations of 100, 1000 ㎍/mL and 1000 ㎍/mL, respectively. However, most of the other macroalgae used in the experiment did not affect NO production. It was observed that all macroalgae extracts except for the highest concentration (1000 ㎍/mL) treatment group of P. tenera did not affect the viability in Raw 264.7 cells. In addition, there was not significant decrease in cell viability by macroalgae extracts treatment in HINAE cells. These results suggest that S. japonica and G. tenax could be used as potential safe natural anti-inflammatory agents for food and feed additives. Also, the results of this study are expected to be used as basic data for the development of functional materials for 10 kinds of macroalgae resources in Korea.

Occurrence of Uranium-238 and Rn-222 in Groundwater and Its Relationship with Helium Isotope (지하수 내 우라늄-238 및 라돈-222 산출과 헬륨 동위원소와의 상관성 연구)

  • Jeong, Chan Ho;Lee, Yu Jin;Lee, Yong Cheon;Hong, Jin Woo;Kim, Cheon Hwan;Nagao, Keisuke;Kim, Young-Seog;Kang, Tae-Seob
    • The Journal of Engineering Geology
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    • v.31 no.4
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    • pp.659-669
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    • 2021
  • The purpose of this study is to elucidate the relationship between occurrence of natural radioactive materials such as 238U and 222Rn and original mixing ratio of helium isotope of groundwater from various geology, and to suggest the underground aquifer environment from helium original mixing data. 9 groundwater samples were collected from five study areas, and 238U, Rn-222 and helium isotope were analyzed. A high 238U content of the range of 218~477 ㎍ /L in the groundwater occurs in the twomica granite. 4He air-crust mixing ratio and the Rn-222 content show a rough relation, that is, Rn-222 content increases according to the increase of 4He crust mixing ratio. Because of helium and radon are an inert gas, their behavior in underground environment is assumed as an analogous. The 238U content and He isotope in groundwater does not show any distinct correlation. The groundwater can be classified as three groups (air, air-crust mixing, crust-mantle mixing origin) on the diagram of 3He/4He vs 4He/20Ne, which is composed of original mixing line from air-crust-mantle end members. This original mixing of helium can provide the information of underground aquifer characteristic such as the connection with surface environment or isolation condition from air environment.

A Study on Infiltration Process and Physicochemical Influence in the Unsaturated and the Saturated Zone of the Bottom Ashes from Thermal Power Plant (화력발전소 배출 바닥재의 불포화대와 포화대 침투과정과 물리화학적 영향에 대한 연구)

  • Park, Byeong-Hak;Joun, Won-Tak;Ha, Seoung-Wook;Kim, Yongcheol;Choi, Hanna
    • Economic and Environmental Geology
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    • v.55 no.1
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    • pp.97-109
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    • 2022
  • This study focused on the physicochemical effects of bottom ash dissolved precipitation on the soil and groundwater environment. The iced column and percolation experiments showed that most of the bottom ash particles were drained as the ash-dissolved solution, while the charcoal powder was filtered through the soil. Ion species of Al, As, Cu, Cd, Cr, Pb, Fe, Mn, Ca, K, Si, F, NO3, SO4 were analyzed from the eluates collected during the 24 h column test. In the charcoal powder eluates, a high concentration of K was detected at the beginning of the reaction, but it decreased with time. The concentrations of Al and Ca were observed to increase with time, although they existed in trace amount. In the bottom ash eluates, the concentrations of Ca and SO4 decreased by 30 mg·L-1 and 67 mg·L-1, respectively, over 24 h. It is regarded that the infiltration patterns of the bottom ash and biochar in the unsaturated zone were different owing to their particle sizes and solvent properties. It is expected that a significant amount of the bottom ash will mix with the precipitation and percolate below the water table, especially in the case of thin and highly permeable unsaturated zone. The biochar was filtered through the unsaturated zone. The biochar did not dissolve in the groundwater, although it reached the saturation zone. For these reasons, it is considered that the direct contamination by the bottom ash and biochar are unlikely to occur.

Floristic Characteristics of Vascular Plants in the Goyangsan Mtn.(Jeongseon-gun) and Munraesan Mtn.(Jeongseon-gun) Area (고양산(1,152.3m, 정선군)과 문래산(1,082.5m, 정선군) 일원의 관속식물)

  • Kim, Young-Chul;Chae, Hyun-Hee;Park, You-Cheol;Lee, Seon-Mi
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.220-256
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    • 2022
  • The most important thing for conserving plant diversity in an area is to make an overall inventory of the plant species inhabiting the area. In particular, limestone areas are known for their high plant diversity and distribution of specific plants. Despite that, only a few have been designated as protected areas. This study investigated the vascular plants distributed in Goyangsan Mtn. and Munraesan Mtn., located in limestone areas of the central part of the Korean Peninsula. A field survey was conducted eight times from April to October 2021. As a result, we identified a total of 654 taxa comprising 113 families, 357 genera, 592 species, 15 subspecies, 44 varieties, and 3 formulas. They included four endangered wild plant species: Astilboides tabularis, Eleutherococcus senticosus, Cypripedium macranthos, and Epilobium hirsutum. Endemic plants in Korea were identified as 32 taxa. Floristic target plants were identified as 168 taxa, specifically 5 taxa of grade V, 41 taxa of grade IV, and 36 taxa of grade III. The red data plants included 2 taxa as "Endangered (EN)", 7 taxa as "Vulnerable (VU)", and 7 taxa as "Near threatened (NT)". A total of 41 taxa of naturalized plants were identified, and 4 of them were invasive alien plants. The surveyed vicinity of Goyangsan Mtn. and Munraesan Mtn. showed high plant diversity and contained core habitats for distribution of an endangered wild plant, Astilboides tabularis,in the limestone area. Moreover, both mountains contained a small population of Cotoneaster integerrimus. These findings confirm that the area has conservation values. Therefore, we propose to identify areas with high plant diversity and designate them as special protected areas.

Increased Water Resistance and Adhesion Force to Skin through the Hybrid of Fatty Acid Ester and Titanium Dioxide (지방산 에스테르와 티타늄다이옥사이드의 복합화를 통한 내수성과 피부 밀착력 개선)

  • Ji Yeon Hong;Chi Je Park;Yong Woo Kim;Sang Keun Han;Sung Bong Kye;Ho Sik Roh;Soo Nam Park
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.3
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    • pp.247-258
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    • 2023
  • This study aims to investigate the enhancement of water resistance and improvement in adhesion to the skin by combining dextrin palmitate and isopropyl titanium triisostearate coating materials with titanium dioxide. Due to the recent increase in consumers who enjoy outdoor activities, the demand for sunscreen with excellent water resistance is increasing. Prior research was conducted with O/W, Pickering, and W/O/W multiple formulations, but there was a limit to water resistance. The purpose of this study is to develop a complex inorganic powder that can improve water resistance and increase adhesion to the skin to solve this problem. First, we combined dextrin palmitate and isopropyl titanium triisostearate coating materials to form a composite with titanium dioxide. The coating of the inorganic powder was confirmed using FE-SEM and FT-IR analysis. The composite exhibited significantly higher in vitro water resistance compared to other formulations. The hydrophobicity of the coated inorganic powder was compared by measuring the contact angles. When the coated inorganic powder was applied to the W/O sunscreen formulation and the non-coated inorganic powder was applied to the W/O sunscreen formulation as a control, the SPF of the sunscreen containing the coated inorganic powder was higher. These results were the same when observed with a UV camera. Finally the adhesion of the coated inorganic powder to the skin was assessed by applying it to a foundation product. In vivo study, it was observed that the product formulated with the coated powder exhibited less smudging compared to the foundation product formulated with the non-coated powder. The developed inorganic powder in this study demonstrated excellent adhesion to the skin, providing a superior sensory experience, as well as enhanced hydrophobicity and remarkable water resistance effects. In the future, the result of this study is expected to help develop various sunscreen products to improve water resistance.

The Contents of Namsan Park Records at the Seoul Metropolitan Archives (서울기록원 소장 남산공원 기록물의 현황과 내용)

  • Kim, Jung-Hwa;Gil, Jihye;Seo, Young-Ai;Park, Hee-Soung;Choi, Hyeyoung;Lee, Myeong-Jun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.6
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    • pp.110-123
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    • 2022
  • Namsan Park in Seoul was designated as a "grand park" in 1954 and is currently operated as an 'Urban Nature Park Area' and four 'neighborhood parks.' However, despite the park's historical and cultural value as an urban park, it has been discussed mainly from a perspective revolving around notions of a mountain or a city wall. To ensure a comprehensive exploration of Namsan Park's history, this study examined public records at the Seoul Metropolitan Archives (SMA), which houses the city's permanent records for preservation and organization. To this end, documents in the SMA Database (DB) were analyzed, yielding 1,359 records concerning Namsan Park. Based on the contents, general characteristics of the urban park were identified through production periods, record types, and disclosure types. Then, essential keywords concerning organizations, people, geographical areas, subjects, and business functions were examined. Finally, the contents and characteristics of Namsan Park in public records were scrutinized, focusing on specific spaces. This research also uncovered important information, such as park drawings, photos, planting lists, plant parcel lists, and significant discussions and decisions regarding the operation and management of the park. Although the public records do not contain a comprehensive history of Namsan Park, it was possible to check the primary historical changes and deliberation processes pertaining to the park's history. Therefore, continuous research intended to interpret and describe public records is expected to identify many implications. In addition, because the public records showed heterogeneous characteristics that center on specific periods and events, an essential task is to advance collaboration and networking with various related institutions, designers, researchers, and citizens.

Classification of Service Quality for HMR unmanned store business (HMR 무인매장 서비스 품질 분류에 관한 연구)

  • Jong Won Lee
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.41-61
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    • 2023
  • The universal form of life in the era of the 4th industrial revolution can probably be summarized as the keyword "non-face-to-face". In particular, in terms of consumption activities, face-to-face contact is gradually changing to a system that minimizes, and offline stores are rapidly changing to non-contact services through kiosks and robots. The social structure is also changing with the passage of time, and most fundamentally, our dietary consumption patterns are changing. In particular, the increase in single-person households and the aging population are having a great impact on changes in the food service industry, which is closely related to dietary life. The HMR (Home Meal Replacement) market has grown significantly as the labor of cooking at home has decreased and the use of substitute foods has increased. As the size of the market has grown, the types of businesses that provide products have also diversified. The development of technology, non-face-to-face culture, and corporate management efficiency are intertwined, and unmanned stores are spreading recently. In this study, service quality attributes of HMR unmanned stores, where competition is gradually intensifying, are classified, and service quality classification using the Kano model and Timko's customer satisfaction coefficient are calculated to provide implications for service management based on customer satisfaction. As a result of the analysis, 'products with short cooking time' and 'variety of products (menu)' were classified as attractive qualities, and 'cleanliness inside/outside of the store' and 'products at reasonable prices' were classified as unified quality. In addition, 'convenience of self-checkout process' was classified as a natural quality, and 'convenience of in-store passage' was classified as an indifferent quality. Furthermore, when the service factor was satisfied within the HMR unmanned store, the factor with the highest satisfaction coefficient was 'product (menu) variety', and the factor with the highest dissatisfaction factor was 'convenience of self-checkout process'. Through the results of this study, it is intended to derive priorities in service quality management of HMR unmanned stores and provide strategic implications for related businesses.

Influence of a chemical additive on the reduction of highly concentrated ammonium nitrogen(NH4+-N) in pig wastewater (양돈 폐수로부터 고농도 암모니아성 질소의 감소를 위한 화학적 첨가제의 영향)

  • Su Ho Bae;Eun Kim;Keon Sang Ryoo
    • Korean Journal of Environmental Biology
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    • v.40 no.3
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    • pp.267-274
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    • 2022
  • Excess nitrogen (N) flowing from livestock manure to water systems poses a serious threat to the natural environment. Thus, livestock wastewater management has recently drawn attention to this related field. This study first attempted to obtain the optimal conditions for the further volatilization of NH3 gas generated from pig wastewater by adjusting the amount of injected magnesia (MgO). At 0.8 wt.% of MgO (by pig wastewater weight), the volatility rate of NH3 increased to 75.5% after a day of aeration compared to untreated samples (pig wastewater itself). This phenomenon was attributed to increases in the pH of pig wastewater as MgO dissolved in it, increasing the volatilization efficiency of NH3. The initial pH of pig wastewater was 8.4, and the pH was 9.2 when MgO was added up to 0.8 wt.%. Second, the residual ammonia nitrogen (NH4+-N) in pig wastewater was removed by precipitation in the form of struvite (NH4MgPO4·6H2O) by adjusting the pH after adding MgO and H3PO4. Struvite produced in the pig wastewater was identified by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analysis. White precipitates began to form at pH 6, and the higher the pH, the lower the concentration of NH4+-N in pig wastewater. Of the total 86.1% of NH4+-N removed, 62.4% was achieved at pH 6, which was the highest removal rate. Furthermore, how struvite changes with pH was investigated. Under conditions of pH 11 or higher, the synthesized struvite was completely decomposed. The yield of struvite in the precipitate was determined to be between 68% and 84% through a variety of analyses.

Analysis of Paint Used for a Helicopter Operated in the Korean War through the History of Paint Application (페인트 도장의 역사를 통해 본 6·25전쟁 운용 헬기의 도료분석)

  • Kang Hyunsam;Jang Hanul;Choi Yangho
    • Conservation Science in Museum
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    • v.29
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    • pp.133-152
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    • 2023
  • This study references preceding studies to examine the history of paint application techniques using various paints in the past, with the aim to contribute to the long-term preservation of large military cultural heritage assets situated outdoors. To this end, the study compared the findings of preceding research with the findings of an analysis conducted on a H-13 helicopter housed at the War Memorial of Korea. Upon collecting and analyzing samples from three grounded WWII aircraft from above-ground by preceding studies, it was confirmed from each sample that the various chemical properties of chrome ensured the effectiveness of the protective coating. The compound was first tested as a corrosion-inhibiting pigment in the early 1940s and proved its excellent moisture-resistant properties over the course of 80 years, despite the deterioration of the paint layer and long-term exposure to the natural environment. For this reason, it has been widely used as a corrosion inhibitor for aluminum alloys in the aviation industry. In other word, the most widely-used material for preventing corrosion was an organic primer containing chromate. In this study, based on the paint analysis of a H-13 helicopter operated in the Korean War, it was shown that the second layer, consisting of the primer, contains chromium oxide (Cr2O3). In addition, it was estimated that red lead tetraoxide (Pb3O4) was used for the vehicle. Analysis results and data from previous studies can help to confirm the continued effectiveness of corrosion prevention function provided by chromate. Meanwhile, the result of infrared spectroscopy analysis confirmed the use of alkyd resin. In the future, comparisons with a more diverse range of artifacts will allow the identification of changes in the manufacturing technology of paints used to protect alloys from corrosion.