• Title/Summary/Keyword: 과학 전공

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A Study on the Research Topics and Trends in South Korea: Focusing on Particulate Matter (토픽모델링을 이용한 국내 미세먼지 연구 분류 및 연구동향 분석)

  • Park, Hyemin;Kim, Taeyong;Kwon, Daewoong;Heo, Junyong;Lee, Juyeon;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.873-885
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    • 2022
  • The particulate matter (PM) has emerged as a hot topic around the world as it has been reported that PM is related to an increase in mortality and prevalence rates. In South Korea, the importance of PM has been recognized since the late 1990s, and various studies on PM have been conducted. This study investigated the PM research topics and trends for papers (D=2,764) published in Research Information Sharing Service (RISS) using topic modeling based on Latent Dirichlet Allocation (LDA). As a result, a total of 10 topics were identified in the whole papers, and the PM research topics were classified as 'PM reduction (Topic 1)', 'Government policy and management (Topic 2)', 'Characteristics of PM (Topic 3)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', 'Bio (Topic 6)', 'Traffic (Topic 7)', 'Asian dust (Topic 8)', 'Indoor PM (Topic 9)', 'Human risk (Topic 10)'. In particular, the proportion of papers on topics 'Government policy and management (Topic 2)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', and 'Bio (Topic 6)' to the toal number of papers increased over time (linear slope > 0). The results of this study provide the new literature review methodology related to particulate matter and the history and insight.

Effect of Tetramethylpyrazine on Pro-Inflammatory Cytokine Expressions in Mouse Brain Tissue following Intracerebroventricular Lipopolysaccharide Treatment (Tetramethylpyrazine이 LPS의 뇌실주입에 따른 생쥐 뇌조직의 Pro-Inflammatory Cytokines 발현에 미치는 영향)

  • Choi, Yong-Seok;Won, Jong-Woo;Yoo, Inwoo;Shin, Jung-Won;Kim, Seong-Joon;Sohn, Nak-Won
    • The Korea Journal of Herbology
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    • v.28 no.1
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    • pp.83-90
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    • 2013
  • Objectives : Tetramethylpyrazine (TMP) is an active ingredient in Ligusticum wallichii and has a wide range of neuroprotection effects. This study investigated anti-neuroinflammatory effect of TMP on brain regions in intracerebroventricular (i.c.v.) lipopolysaccharide (LPS)-treated C57BL/6 mice. Methods : TMP was administered intraperitoneally at doses of 10, 20, and 30 mg/kg at 1 h prior to LPS (3 mg/kg) i.c.v. injection. mRNA level of pro-inflammatory cytokines, including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$ and IL-6, was measured in the cerebral cortex, hippocampus, and hypothalamus tissue using real-time polymerase chain reaction at 24 h after the LPS injection. Cyclooxygenase-2 (COX-2) positive cells in the hypothalamus was also observed using immunohistochemistry at 24 h after the LPS injection. Results : At a dose of 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$ and IL-$1{\beta}$ mRNA in the cerebral cortex and IL-$1{\beta}$ mRNA in the hippocampus. In the hypothalamus, doses of 20 mg/kg and 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 mRNA induced by the LPS injection. In addition, TMP (30 mg/kg) significantly reduced the number of COX-2 positive cells in the hypothalamus. Conclusion : These results indicate that TMP has an anti-inflammatory effect on neuroinflammation, especially in the hypothalamus, induced by LPS i.c.v. injection and suggest that TMP-containing Ligusticum wallichii may play a modulatory role on the systemic responses following hypothalamic inflammation.

Effects of β-Asarone on Pro-Inflammatory Cytokines and Learning and Memory Impairment in Lipopolysaccharide-Treated Mice (β-Asarone이 Lipopolysaccharide에 의한 생쥐 해마의 염증성 사이토카인 발현과 학습 및 기억 장애에 미치는 영향)

  • Choi, Moon-Sook;Kwak, Hee-Jun;Kweon, Ki-Jung;Hwang, Ji-Mo;Shin, Jung-Won;Sohn, Nak-Won
    • The Korea Journal of Herbology
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    • v.28 no.6
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    • pp.119-127
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    • 2013
  • Objectives : ${\beta}$-Asarone (BAS) is an active ingredient in Acori Rhizoma. This study investigated anti-neuroinflammatory and memory ameliorating effects of BAS in systemic lipopolysaccharide (LPS)-treated C57BL/6 mice. Methods : BAS was administered orally at doses of 7.5, 15, and 30 mg/kg for 3 days prior to LPS (3 mg/kg, intraperitoneal) injection. Pro-inflammatory cytokine mRNA, including tumor necrosis factor-${\alpha}$ (TNF-ㅍ), interleukin (IL)-$1{\beta}$ and IL-6, was measured in hippocampus tissue using real-time polymerase chain reaction at 4 h after the LPS injection. An ameliorating effect of 30 mg/kg BAS on learning and memory impairment in the LPS-treated mice was verified using the Morris water maze test. Results : BAS significantly attenuated up-regulation of TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 mRNA in hippocampus tissue of the LPS-treated mice. In acquisition training test, BAS improved learning performance of the LPS-treated mice with a significant decrease of escape latency to the platform. In memory retention test, BAS also ameliorated memory impairment of the LPS-treated mice with a significant increase of swimming time in zones neighboring to the platform, number of target heading, and memory score. Conclusion : The results suggest that inhibition of pro-inflammatory cytokines and neuroinflammation in the hippocampus by BAS could be one of the mechanisms for BAS-mediated ameliorating effect on learning and memory impairment in LPS-treated mice.

Effect of Ginsenoside Rg3 on COX-2 Expression in Brain Tissue of Lipopolysaccharide-Treated Mice (Ginsenoside Rg3이 Lipopolysaccharide에 의한 생쥐 뇌조직의 Cyclooxygenase-2 발현에 미치는 영향)

  • Choi, Wonik;Cho, Yong-Deok;Lee, Joon-Seok;Shin, Jung-Won;Kim, Seong-Joon;Sohn, Nak-Won
    • The Korea Journal of Herbology
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    • v.27 no.6
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    • pp.131-137
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    • 2012
  • Objectives : Cyclooxygenase (COX) plays a central role in the inflammatory cascade by converting arachidonic acid into prostaglandin. COX-2 is typically induced by inflammatory stimuli in the majority of tissues, it is responsible for propagating the inflammatory response and thus, considered as the best target for anti-inflammatory drugs. The present study investigated the modulatory effect of ginsenoside Rg3, a principle active ingredient in Panax ginseng, on COX-2 expression in the brain tissue induced by systemic lipopolysaccharide (LPS) treatment in C57BL/6 mice. Methods : Because systemic LPS treatment induces COX-2 expression immediately in the brain, ginsenoside Rg3 was treated orally with doses of 10, 20, and 30 mg/kg at 1 hour before the LPS (3 mg/kg, i.p.) injection. At 4 hours after the LPS injection, COX-2 mRNA was measured by real-time polymerase chain reaction method, COX-2 protein levels were measured by Western blotting. In addition, COX-2 expressions in brain tissue were observed with immunohistochemistry and double immunofluoresence labeling. Results : Ginsenoside Rg3 (20 and 30 mg/kg) significantly attenuates up-regulation of COX-2 mRNA and protein expression in brain tissue at 4 hours after the LPS injection. Moreover, ginsenoside Rg3 (20 mg/kg) significantly reduced the number of COX-2 positive neurons in the cerebral cortex and amygdala. Conclusion : These results indicate that ginsenoside Rg3 plays a modulatory role in neuroinflammation through the inhibition of COX-2 expression in the brain and suggest that ginsenoside Rg3 and ginseng may be effective on neurodegenerative diseases caused by neuroinflammation.

Estimation of the Source Adult Population for Agrotis ipsilon (Lepidoptera: Noctuidae) Appearing in Early Spring in Korea: An Approach with Phenology Modeling (국내에서 이른 봄 출현하는 검거세미밤나방 성충집단의 기원 추정: 페놀로지 모형을 통한 접근)

  • Sori Choi;Jinwoo Heo;Subin Kim;Myeongeun Jwa;Yonggyun Shin;Dong-Soon Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.1
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    • pp.37-47
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    • 2023
  • The black cutworm, Agrotis ipsilon (Hufnagel), is an important crop pest worldwide that feeds more than 80 plant species including cabbage, potato, maize, wheat and bean, and this moth is a typical pest attacking underground parts of crops. It has been known in farm booklets that the larvae of A. ipsilon overwinter in the soil in Korea, but no definitive data exist yet. This study was conducted to evaluate that the specific appearance time of A. ipsilon observed actually in the field could be explained when we assumed that this pest overwinters in a form of larvae or pupae. Degree day-based phenology models were applied for tracking forward or backward to find the predicted developmental stage which developed at a specific stage found in the field. As a result of the analysis, it was confirmed that an initial population could be established in a group that does not overwinter as larvae or pupae in Korea. In other words, the appearance of adults in early March to April could not be explained by the presence of domestic overwintering populations. Populations that overwinter as larvae or pupae in Korea were able to emerge as adults in June to July at the earliest. Therefore, the group of adults appearing in early spring is highly likely to be a population that migrated from outside Korea. Taken together, it was estimated that the colony of A. ipsilon in Korea would be formed by a mixture of a migrant population through long-distance migration and a overwintering population.

A Review on Electrochemical Model for Predicting the Performance of Lithium Secondary Battery (리튬이차전지 성능 모사를 위한 전기화학적 모델링)

  • Yang, Seungwon;Kim, Nayeon;Kim, Eunsae;Lim, Minhong;Park, Joonam;Song, Jihun;Park, Sunho;Appiah, Williams Agyei;Ryou, Myung-Hyun;Lee, Yong Min
    • Journal of the Korean Electrochemical Society
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    • v.22 no.1
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    • pp.43-52
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    • 2019
  • As the application area of lithium secondary batteries becomes wider, performance characterization becomes difficult as well as diverse. To address this issue, battery manufacturers have to evaluate many batteries for a longer period, recruit many researchers and continuously introduce expensive equipment. Simulation techniques based on battery modeling are being introduced to solve such difficulties. Various lithium secondary battery modeling techniques have been reported so far and optimal techniques have been selected and utilized according to their purpose. In this review, the electrochemical modeling based on the Newman model is described in detail. Particularly, we will explain the physical meaning of each equation included in the model; the Butler-Volmer equation, which represents the rate of electrode reaction, the material and charge balance equations for each phase (solid and liquid), and the energy balance. Moreover, simple modeling processes and results based on COMSOL Multiphysics 5.3a will be provided and discussed.

The Effect of Major satisfaction, Parents' career support on the Behavior of career preparation among University students (대학생의 전공만족도와 부모의 진로지지가 진로준비행동에 미치는 영향)

  • Kim, Hey-Kyoung
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.3
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    • pp.708-719
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    • 2021
  • The purpose of this study was to investigate the effect of the major satisfaction and parents' career support on the behavior of career preparation among university students and to presents basic data for making active the behavior of career preparation. A survey was held to the university students in Seoul and Chungcheong cities from April 15 to May 14, 2021 195 copies were in the final analysis for data analysis, t-test, ANOVA, Pearson's Correlation Coefficient and Multiple regression was used. As a result, the factors of affecting on the behavior of career preparation were followed by Economic level, Major category, Motivation of the major, Grade, the major satisfaction and parents' career support. The multiple regression explanatory power was 50.5percent of the total changes in the behavior of career preparation. Therefore, this study could be used as a basic data for the development of education programs through increase the major satisfacton and enhance parents career support in order to the active behavior of career preparation.

Analysis of the Composition Concept of Education Service Quality of Beauty Major University (뷰티전공 대학의 교육서비스품질 구성개념 분석)

  • Kang, Se-ryung;Lee, Young-jo
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.2
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    • pp.271-280
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    • 2022
  • The purpose of this study is to investigate the concept of composition of educational service quality through two integrated research methods of open questionnaires and focus group interviews for college students majoring in beauty. Participants in the study majored in beauty at 2-year and 4-year universities nationwide. The enrolled students were set as a population, and 250 people were adopted as a random sampling method and used for the survey. The series of results are as follows. First, as a result of inductive content analysis of open questionnaires, the educational service quality of beauty majors was derived into five areas: major knowledge, educational quality, professor-student intimacy, student needs reflection, usability, curriculum composition, environmental efficiency, educational equipment, and reputation. Second, as a result of the focus group interview, inductive content analysis was more reasonably pointed out and derived in depth. As a result of this study, it is believed that it can be used as basic data for the development of measurement tools for educational service quality of beauty majors.

A Proposal for Partial Automation Preparation System of BIM-based Energy Conservation Plan - Case Study on Automation Process Using BIM Software and Excel VBA - (BIM기반 에너지절약계획서 건축부문 부분자동화 작성 시스템 제안 - BIM 소프트웨어와 EXCEL VBA를 이용한 자동화과정을 중심으로 -)

  • Ryu, Jea-Ho;Hwang, Jong-Min;Kim, Sol-Yee;Seo, Hwa-Yeong;Lee, Ji-Hyun
    • Journal of KIBIM
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    • v.12 no.2
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    • pp.49-59
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    • 2022
  • The main idea of this study is to propose a BIM-based automation system drawing up a report of energy conservation plan in the architecture division. In order to obtain a building permit, an energy conservation plan must be prepared for buildings with a total floor area of 500m2 or more under the current law. Currently, it is adopted as a general method to complete a report by obtaining data and drawings necessary for an energy conservation plan through manual work and input them directly into the verification system. This method takes a lot of effort and time in the design phase which ultimately increases the initial cost of the business, including the services of companies specialized in the environmental field. However, in preparation for mandatory BIM work process in the future, it is necessary to introduce BIM-based automatic creation system that has an advantage for shortening the whole process to enable rapid permission of energy-saving designs for buildings. There may be many methods of automation, but this study introduces how to build an application using Dynamo of Revit, in terms of utilizing BIM, and write an energy conservation plan by automatic completion of report through Dynamo and Excel's VBA algorithm, which can save time and cost in preparing the report of energy conservation plan compared with the manual process. Also we have insisted that the digital transformation of architectural process is a necessary for an efficient use of our automation system in the current energy conservation plan workflow.

Preliminary Results from Sandstone Petrography of the Icheonri Formation in Gijang-gun, Busan: Implications for Provenance and Tectonic Setting (부산 기장군에 분포하는 백악기 이천리층 사암 조성의 예비 연구: 기원지와 조구조 역사 해석에의 의의)

  • Young Ji Joo;Heeseon Yang;Kyeongtae Kim;Hyun Ju Kim
    • Journal of the Korean earth science society
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    • v.44 no.2
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    • pp.161-168
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    • 2023
  • While numerous previous studies investigated the provenance and tectonic history of the Gyeongsang Supergroup, less are known about other Cretaceous strata in South Korea. This study presents preliminary results from petrographic analysis of the Cretaceous Icheonri Formation distributed in Gijang-gun, Busan. Based on the immature texture and composition of the Icheonri sediments, we interpret that they were derived from weakly denudated Cretaceous arc volcanoes developed along the eastern margin of the Asian continent, with limited weathering and transport. Additionally, the presence of chrome spinel grains in the sediments suggests the existence of ultramafic bodies exposed in their provenance. Further studies will advance our understanding of the tectonic developments in the southeastern Gyeongsang Basin, and facilitate a comprehensive correlation between the Icheonri Formation and the Gyeongsang Supergroup.