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Effects of Sowing and Harvesting Times on Feed Value and Functional Component of Triticale (x Triticosecale Wittmack) (트리티케일 파종시기 및 수확시기가 사일리지 사료가치와 기능성 성분에 미치는 영향)

  • Jisuk Kim;Kyungyoon Ra;Yul-Ho Kim;Myoung Ryoul Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.67 no.4
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    • pp.319-325
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    • 2022
  • Triticale forage has the highest yield of all winter forage crops, including rye, and a cold tolerance within an average low temperature of -10℃ in January. Therefore, this study analyzed the effects of sowing and harvesting times on the feed value and functional components of triticale to optimize the use and supply of triticale as livestock fee Room temperature' can vary widely with climate, season, and time of day. In order to clearly state the conditions of the study in a manner that facilitates replication by other researchers, please consider using an approximate temperature range instead. Seeds of the triticale 'Joseong' were sown during the fall of 2021 (October 20th) and spring of 2022 (March 7th). The triticale was harvested at the following growth stages: seedling stage, booting stage, heading stage, 10 days after heading, and 20 days after heading. The moisture content of each harvested triticale was adjusted to approximately 60%, and the triticale was fermented for silage for 40 days at ambient temperature under anaerobic conditions. We measured the pH and organic acid content of each silage to determine the feed value and functional component. The lactic acid content of the triticale silage harvested at the seedling stage sown in both fall and spring (1.61%, 1.63%) was the highest among all the silages. The octacosanol content in the silages of both fall-sown and spring-sown triticale harvested at the seedling stage (0.38, 0.27 mg/ml) was the highest. Overall, the results revealed that harvesting time had a greater impact on the feed value and functional components of triticale silage than sowing time.

Analysis of the Pre-service Chemistry Teachers' Cognition of the Nature of Model in the Design and Development Process of Models Using Technology: Focusing on Boyle's Law (테크놀로지를 활용한 모델의 설계와 개발 과정에서 나타난 예비화학교사의 모델의 본성에 대한 인식 분석: 보일 법칙을 중심으로)

  • Na-Jin Jeong;Seoung-Hey Paik
    • Journal of the Korean Chemical Society
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    • v.67 no.5
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    • pp.378-392
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    • 2023
  • The purpose of this study is to analyze the pre-service chemistry teachers' cognition of the nature of model in process of designing and developing models using technology. For this purpose, 19 pre-service chemistry teachers' in the 3rd grade of a education college located in the central region observe experimental phenomena related to Boyle's law presented in the 7th grade science textbook and researchers required the design and development of a model related to the observed experimental results using technology. Based on previous studies, the nature of model were classified into two aspect: 'Representational aspect' and 'Explanatory aspect'. The 'Representational aspect' was classified into 'Representation', 'Abstraction', and 'Simplification', and the 'Explanatory aspect' was classified into 'Analysis', 'Interpretation', 'Reasoning', 'Explanation', and 'Quantification'. The pre-service chemistry teachers' cognition were analyzed by the classification. As a result of the study, the 'Representation' of the 'expressive aspect' was uniformized in the form of space that changes in volume, and the pressure was expressed as the Brightness inside the cylinder or frequency of color change of particles for 'Abstraction'. In the case of 'Simplification', the particle collision was expressed as a perfectly elastic collision, but there was a group that could not simply indicate the type of particle. In the 'Explanatory aspect', in the case of 'Analysis', volume was classified as a manipulated variable, and in the case of 'Interpretation', most groups analyzed the change in pressure through the collision of gas particles. However, the cognition involved in 'Reasoning' was not observed much. In the case of 'Explanation', there were groups that did not succeed in explanation because the area where the particles collided was not set or incorrectly set, and in the case of 'Quantification', there was a group that formulated the number of collisions per unit time, and on the contrary, there was a group that could not quantify the number of collisions because they could not be expressed in numbers.

Discourse and an Agenda for Religious Publicness: Faith, Sacred Objects, and Holy Sites (종교 공공성의 담론과 의제 - 신앙, 성물과 성지 -)

  • Yoon Yong-bok;Ko Byoung-chul
    • Journal of the Daesoon Academy of Sciences
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    • v.43
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    • pp.31-66
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    • 2022
  • In Korea, the concept of publicness, although conceptually unclear, is being used as a medium between religious groups and other areas of society. In this situation, it is necessary to discuss the concept and agenda of publicness related to religions. For this purpose, we reviewed the relationship and agenda between publicness and faith, and then analyzed the cases of creating sacred objects and holy sites in connection with the concept of publicness. Specifically, according to Chapter II, Publicness and Faith, theologians and sociologists interested in publicness generally presuppose or aim for social participation and change. In this context, the agenda related to religious publicness can include the ground of non-Christian publicness, interreligious equality in the public spheres, the status of religious bodies, and the participation of researchers in the public spheres. In Chapter III, Sacred Objects and Publicness, we divided religious publicness into 'publicness within religion' and 'publicness outside of religion.' According to this classification, rituals are a key factor in creating publicness within religion. Publicness outside of religion is not intrinsic, but is constructed through various external debates. In Chapter IV, Sacred Holy Sites and Publicness, we reviewed cases of the construction of Catholic holy sites and analyzed oppositional logic provided by other religious groups in relation to the publicness outside of religion. Those cases internally created publicness within religion but lead to evaluation and debate about publicness outside of religion in public spheres in which various religions participate. Those who opposed the creation of Catholic holy sites used the logic that Catholicism was eliminating the heritage and values of other religions, and responded by expanding this to include the logic that the Catholics were weakening publicness or creating religious bias.

Changes in Perceptions of Science Classes Using Artificial Intelligence among Elementary Teachers Participating in Research School (연구학교 참여 초등교사의 인공지능 활용 과학 수업에 관한 인식 변화)

  • Kim, Tae Ha;Yoon, Hye-Gyoung
    • Journal of Korean Elementary Science Education
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    • v.42 no.3
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    • pp.467-479
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    • 2023
  • For the successful implementation of education using artificial intelligence (AI) in schools, the perception of teachers is important. This study focuses on elementary school teachers and their perception of the need and teaching efficacy of science classes using AI before and after participating in a research school program. The analysis explores four key aspects, namely, learning, teaching, assessment, and communication. The study recruited 24 elementary school teachers from a school designated by the Gangwon Provincial Office of Education to participate in a year-long research school program. The study collected data using pre- and post-program surveys to explore changes in the perception of teachers regarding AI-based science classes. Furthermore, the researchers conducted individual in-depth interviews with four elementary school teachers to investigate the experience factors that influenced the changes in their perception of the aforementioned classes. The main findings were as follows. First, elementary school teachers were positively aware of the need for science classes using AI even prior to their research school experience; this perception remained positive after the research school program. Second, the science teaching efficacy of the elementary school teachers using AI was generally moderate. Even after the research school experience, the study found no statistically significant increase in efficacy in teaching science using AI. Third, by analyzing the necessity-efficacy as quadrants, the study observed that approximately half of the teachers who participated in the research school reported positive changes in learning, teaching, and assessment. Fourth, the study extracted four important experience factors that influenced the perception of the teachers of science classes using AI, namely, personal background and characteristics, personal class practice experience, teacher community activities, and administration and work of school. Furthermore, the study discussed the implications of these results in terms of the operation of research schools and science education using AI in elementary schools.

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.

Analysis on Dynamics of Korea Startup Ecosystems Based on Topic Modeling (토픽 모델링을 활용한 한국의 창업생태계 트렌드 변화 분석)

  • Heeyoung Son;Myungjong Lee;Youngjo Byun
    • Knowledge Management Research
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    • v.23 no.4
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    • pp.315-338
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    • 2022
  • In 1986, Korea established legal systems to support small and medium-sized start-ups, which becomes the main pillars of national development. The legal systems have stimulated start-up ecosystems to have more than 1 million new start-up companies founded every year during the past 30 years. To analyze the trend of Korea's start-up ecosystem, in this study, we collected 1.18 million news articles from 1991 to 2020. Then, we extracted news articles that have the keywords "start-up", "venture", and "start-up". We employed network analysis and topic modeling to analyze collected news articles. Our analysis can contribute to analyzing the government policy direction shown in the history of start-up support policy. Specifically, our analysis identifies the dynamic characteristics of government influenced by external environmental factors (e.g., society, economy, and culture). The results of our analysis suggest that the start-up ecosystems in Korea have changed and developed mainly by the government policies for corporation governance, industrial development planning, deregulation, and economic prosperity plan. Our frequency keyword analysis contributes to understanding entrepreneurial productivity attributed to activities among the networked components in industrial ecosystems. Our analyses and results provide practitioners and researchers with practical and academic implications that can help to establish dedicated support policies through forecast tasks of the economic environment surrounding the start-ups. Korean entrepreneurial productivity has been empowered by growing numbers of large companies in the mobile phone industry. The spectrum of large companies incorporates content startups, platform providers, online shopping malls, and youth-oriented start-ups. In addition, economic situational factors contribute to the growth of Korean entrepreneurial productivity the economic, which are related to the global expansions of the mobile industry, and government efforts to foster start-ups. Our research is methodologically implicative. We employ natural language processes for 30 years of media articles, which enables more rigorous analysis compared to the existing studies which only observe changes in government and policy based on a qualitative manner.

Sensitivity analysis of the FAO Penman-Monteith reference evapotranspiration model (FAO Penman-Monteith 기준증발산식 민감도 분석)

  • Rim, Chang-Soo
    • Journal of Korea Water Resources Association
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    • v.56 no.4
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    • pp.285-299
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    • 2023
  • Estimating the evapotranspiration is very important factor for effective water resources management, and FAO Penman-Monteith (FAO P-M) model has been applied for reference evapotranspiration estimation by many researchers. However, because various input data are required for the application of FAO P-M model, understanding the effect of each input data on FAO P-M model is necessary. Therefore, in this study, for 56 study stations located in South Korea, the effects of 8 meteorological factors (maximum and minimum temperature, wind speed, relative humidity, solar radiation, vapor pressure deficit, net radiation, ground heat flux), energy and aerodynamic terms of FAO P-M model, and elevation on FAO P-M reference evapotranspiration (RET) estimation were analyzed. The relative sensitivity analysis was performed to determine how 10% increment of each specific independent variable affects a reference evapotranspiration under given set of condition that other independent variables are unchanged. Furthermore, to select the 5 representative stations and perform the monthly relative sensitivity analysis for those stations, 56 study stations were classified into 5 clusters using cluster analysis. The study results showed that net radiation was turned out to be the most sensitive factor in 8 meteorological factors for 56 study stations. The next most sensitive factor was relative humidity, solar radiation, maximum temperature, vapor pressure deficit and wind speed, followed by minimum temperature in order. Ground heat flux was the least sensitive factor. In case of ground surface condition, elevation showed very low positive relative sensitivity. Relativity sensitivities of energy and aerodynamic terms of FAO P-M model were 0.707 for energy term and 0.293 for aerodynamic term respectively, indicating that energy term was more contributable than aerodynamic term for reference evapotranspiration. The monthly relative sensitivities of meteorological factors showed the seasonal effects, and also the relative sensitivity of elevation showed different pattern each other among study stations. Therefore, for the application of FAO P-M model, the seasonal and regional sensitivity differences of each input variable should be considered.

Isolation and Characterization of the Indigenous Microalgae Chlamydomonas reinhardtii K01 as a Potential Resource for Lipid Production and Genetic Modification (지질생산 및 유전자 조작의 잠재적 자원으로서의 토착 미세조류 Chlamydomonas reinhardtii K01의 분리 및 특성)

  • Kim, Eun-Kyung;Cho, Dae Hyun;Suh, Sang-Ik;Lee, Chang-Jun;Kim, Hee-Sik;Suh, Hyun-Hyo
    • Journal of Life Science
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    • v.32 no.3
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    • pp.202-209
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    • 2022
  • The green alga Chlamydomonas reinhardtii, a unicellular haploid eukaryote, has long been used by researchers and industries as a cell factory to produce high value-added microalgae substances using genetic modification. Microalga K01, presumed to be Chlamydomonas, was isolated from 12 freshwater samples from the Chungcheong and Jeolla regions to replace C. reinhardtii, an introduced species currently used in most basic and industrial research. The isolated K01 strain was identified as C. reinhardtii through morphological and phylogenetic studies of the 18S rDNA gene sequence (NCBI accession number KC166137). The growth and lipid content of the isolated C. reinhardtii K01 were compared with three wild and four mutant strains in TAP medium, and it was found that the K01 strain could produce 1.74×107 cells/ml by the third day of culture. The growth rate of C. reinhardtii K01 was 1.5 times faster than UTEX2244, which showed the highest number of cells (1.20×107 cells/ml) among the compared strains. The lipid content of the isolated C. reinhardtii K01 (20.67%) was similar to those of the wild strains, although the fatty acid oleate C18:1 was not detected in the isolated strain but was identified in the seven others. The cell density of the isolated strain increased to 0.87 g/l during a six-day culture in BG11 medium, where nitrate (NaNO3) was introduced as a nitrogen source, while the seven acquired strains showed almost no cell proliferation.

Research Trend of Estuarine Ecosystem Monitoring and Assessment (국내 하구 수생태계 현황 및 건강성 조사의 성과와 하구 생태계의 국외 연구동향)

  • Won, Doo-Hee;Lim, Sung-Ho;Park, Jihyung;Moon, Jeong-Suk;Do, Yuno
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.1-9
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    • 2022
  • An estuary is an area where a freshwater river or stream meets the ocean. Even before the importance of the value of estuaries was recognized, the estuary was lost because of large-scale conversion by draining, filling, damming, and dredging. In South Korea, 643 estuaries are located, and the total area is 3,248,300 ha, accounting for 32.5% of the total area of South Korea. Over 35% of Korean estuaries are closed estuaries which are only temporally connected with the sea, either permanently or periodically. Since 2008, in order to preserve the estuary ecosystem and solve major issues in the estuary by accumulating knowledge about the estuarine ecosystem, the Ministry of Environment of Republic of Korea has been conducting the "Estuarine Ecosystem Monitoring and Assessment Project". At 668 sites of 325 estuaries, epilithic diatom, benthic macroinvertebrate, fish, and vegetation are investigated, and the habitat condition of each site is evaluated using the newly developed biotic index. More than 100 researchers annually record 2,097 species of estuaries according to the standardized survey guidelines over the past 14 years and provide strictly managed data necessary for establishing estuaries conservation policies. As a result of bibliometric analysis of 1,195 research articles related to the monitoring and assessment of the estuarine ecosystem, research on pollutants such as heavy metals and sediment control have recently been conducted. "Estuarine Ecosystem Monitoring and Assessment Project" is an ecological monitoring type of long-term mandated monitoring that is usually focused on identifying trends. Although it is difficult to identify the mechanism influencing a change in an ecosystem through long-term mandated monitoring, providing empirical data for supporting evidence-based policy, decision-making, and the management of ecosystems. In order to increase the efficiency of the project, research to investigate the relationship between sediments and pollutants and organisms can be conducted at specific estuaries or sites to compensate for the shortcomings of mandatory monitoring.

The Science-Related Attitudes from Adults' Experiences during Science Cultural Activities: Focusing on the Case of Science Fiction Discussions (성인들의 과학문화 활동 경험에서 나타난 과학 관련 태도 -과학소설 독서토론 활동 사례를 중심으로-)

  • Eunji Kang;Chaeyeon Shin;Jinwoong Song
    • Journal of The Korean Association For Science Education
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    • v.43 no.2
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    • pp.139-150
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    • 2023
  • This study started with the awareness of the need to explore various aspects of science education and was conducted according to the necessity of practical research on science cultural activities targeting adults. Accordingly, adults' book discussions of science fiction were selected as research cases, and science-related attitudes in science cultural activities were explored. There are four participants in the study, all of whom have engaged in a book club and have not majored or are working in science disciplines. Three science fictions were selected after establishing specific standards for the selection discussed with participants. For four months, a total of three unstructured book discussions of science fiction, post-interviews for each discussion, and in-depth individual interviews after the end of the entire activity were conducted. Various data such as recorded and transcribed reading discussion discourse, post- and in-depth individual interviews, researchers' observation records, and participants' book journals were collected and analyzed using a continuous comparison method. As a result of the study, as scientific thinking is illustrated in SF, the participants also demonstrated scientific attitudes during their discussions. In addition, the textual feature(storytelling) of science fiction was found to lessen cognitive overload and the burden of understanding science by providing scientific knowledge with context. Finally they demonstrated a shift in attitude toward science, valuing science cultural activities in themselves, rather than simply viewing science as a subject of understanding and learning. The conclusions and meanings of this study based on the above results are presented to enhance a positive attitude toward science for adults even after school education.