• Journal of Science Education
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• v.35 no.2
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• pp.204-220
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• 2011

This study was intended to develop an experimental module based on inquiry processes conducted by photosynthesis scientists. It was aimed to enhance scientific inquiry ability of the middle school students by applying the developed module. Developed module included some experiments conducted by earlier photosynthesis scientists such as Helmont, Woodward, Priestly, Hales and Ingen-Hausz. Inquiry process was involved in the developed module for instructing the inquiry methods. Rapid-cycling Brassica rapa known as a Fast Plant was used for the experimental material. Developed module was applied to the experimental group consisting 27 eighth grader, while experiments suggested in the science textbook was applied to the control group consisting 30 eighth grader. Developed module was more effective in improving students' scientific inquiry ability, especially measuring, forecasting and hypothesizing ability as its subordinate elements. When the result of post-test was compared to one of pre-test in the experimental group, their observing, forecasting, and generalization ability were improved. Experimental group showed that students' conception in photosynthesis and conceptual development related with the role of plants in the ecosystem and plant's food and movement of the water and nutrients were also improved. Before application, students in the experimental group did not have enough understanding of the abstract concept such as the existence or the role of the materials like $CO_2$ or $O_2$ or the energy accumulation. Developed module could help students to achieve the comprehensive concept regarding the role of plants as producers of organic matter and oxygen and to enhance their scientific inquiry ability and concepts regarding photosynthesis.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.412-417
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• 2003

작물의 생장상태를 측정하고자 기존의 연구자들에 의해서 많은 연구가 수행되고 있다. 그러나 작물의 생장을 감시하기 위한 기존의 방법은 파괴적이며 지속적이지 못하다는 단점을 지니고 있다. 작물이 생장 장해를 받아 눈에 띄게 작물의 생장변화가 보일 경우 작물은 이미 영구적인 손상을 받게 진다. 따라서 이런 작물의 생장 장해를 조기에 진단하여 작물의 생장 장해에 능동적으로 반응할 수 있는 방법의 개발이 절실히 요구된다. (중략)

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.1
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• pp.82-88
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• 2021

Sun-induced fluorescence (SIF) retrieval using remote sensing technique has been used in an effort to understand the photosynthetic efficiency and stress condition of vegetation. Although optical devices and SIF retrieval methodologies were established in order to retrieve SIF, the SIF measurements are domestically sparse. SIF data of paddy rice w as measured in Naju, South Korea from June 10, 2020 to October 5, 2020. The SIFs based red (O2A) and far-red (O2B) w ere retrieved using a spectral fitting method and an improved Fraunhofer line depth, and photosynthetically active radiation was also produced. In addition, the SIF data was filtered considering solar zenith angle, saturation conditions, the rapid and sudden change of solar irradiance, and sun glint. The provided SIF data can help to understand a SIF product and the filtering method of SIF data can contribute to producing high-quality SIF data.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.221-237
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• 2010

To estimate marine primary production, satellite data are essential for providing much better spatial and temporal resolutions. However, primary production estimation for turbid coastal water such as the Yellow Sea still needs much improvement. Here we evaluate currently available methods of primary production estimation in the Yellow Sea. We focus on comparison of eight combinations from four chlorophyll-a algorithms and two primary production algorithms of the Yellow Sea. Estimated primary production by the eight combinations ranged from 96.5 to $610.2\;gC\;m^{-2}\;yr^{-1}$ in the central region of the Yellow Sea. The new chlorophyll algorithms (presently under development by Korea, China, and Japan scientists) are expected to improve the retrieval of chlorophyll-a in turbid regions compared to the standard algorithm but there are certain unresolved problems. The new algorithm for primary production (which uses adjusted physiological parameters with in-situ data) also needs further improvement.

• Journal of The Korean Association For Science Education
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• v.35 no.6
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• pp.1019-1030
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• 2015

This study examined the development of a teacher's teaching practice and identified argumentation-specific pedagogical content knowledge (PCK) and the influence of the argumentation-specific PCK on teaching practice in an argumentation classroom. The teacher has a Ph.D degree in science education, a 19-year teaching career, and no experience in instructing in an argumentation classroom. The developed program consists of nine lessons regarding photosynthesis for 7th graders. The teacher participated in a collaborative reflection with researchers after each lesson once a week and five times in total, which lasted for thirty minutes. All of the lessons were video- and audio-recorded and the transcript of lessons and collaborative reflection, pre- and post-survey related to argumentation, and researchers' journals were analyzed. Analysis of the data showed that the teacher emphasized group interaction showing utterances of listening, evaluating arguments, counter-arguing/debating, and reflecting on argument process after the fourth lesson although the teacher focused on individual argumentation showing utterances of talking, knowing meaning of argument, and justifying with evidence in the first three lessons. Also, the argumentation-specific PCK, which was identified with the understanding of students, nature of argumentation and argumentation task strategy, also influenced the development of teaching practice. The teacher comprehended the students' challenges in argumentation, developed her understanding of the nature of argumentation from an individual plane to social plane, and demonstrated a deep understanding of the task strategy by voluntarily joining in modifying the argumentation tasks.

• Journal of Mushroom
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• v.18 no.1
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• pp.1-9
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• 2020

Mycorrhiza refers to the association between a plant and a fungus colonizing the cortical tissue of the plant's roots during periods of active plant growth. The benefits afforded by plants from mycorrhizal symbioses can be characterized either agronomically, based on increased growth and yield, or ecologically, based on improved fitness (i.e., reproductive ability). In either case, the benefit accrues primarily because mycorrhizal fungi form a critical linkage between plant roots and the soil. The soilborne or extramatrical hyphae take up nutrients from the soil solution and transport them to the root. This mycorrhizae-mediated mechanism increases the effective absorptive surface area of the plant. There are seven major types of mycorrhizae along with mycoheterotrophy: endomycorrhizae (arbuscular mycorrhizae, AM), ectomycorrhizae (EM), ectendomycorrhizae, monotropoid, arbutoid, orchid, and ericoid. Endomycorrhizal fungi form arbuscules or highly branched structures within root cortical cells, giving rise to arbuscular mycorrhiza, which may produce extensive extramatrical hyphae and significantly increase phosphorus inflow rates in the plants they colonize. Ectomycorrhizal fungi may produce large quantities of hyphae on the root and in the soil; these hyphae play a role in absorption and translocation of inorganic nutrients and water, and also release nutrients from litter layers by producing enzymes involved in mineralization of organic matters. Over 4,000 fungal species, primarily belonging to Basidiomycotina and to a lesser extent Ascomycotina, are able to form ectomycorrhizae. Many of these fungi produce various mushrooms on the forest floor that are traded at a high price. In this paper, we discuss the benefits, nutrient cycles, and artificial cultivation of mycorrhizae in Korea.