• Research in Mathematical Education
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• v.1 no.2
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• pp.127-137
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• 1997

수세기는 초등 수학교육의 기초로서 보통 유치원 과정 이전부터 시작된다. 그러나, 서수와 기수의 구별된 사용의 중요성은 미국의 "학교 수학의 교과 과정과 평가 기준" (NCTM 1989)에서 뿐만 아니라 학교 교육의 현장에서도 많이 간과되고 있는 실정이다. 일반적으로 사용되는 수직선 (Number line)과 다르게 구조적으로 개발된 Hasse's structured number line을 사용하여 학생들에게 수세기의 의미와 기술을 가르친다면 구체적 경험을 통해 수학적 사고 능력을 키우고 개발하는데 도움이 된다. 만약 Hasse 의 9가지 수준에 따라 다양한 학습 활동을 개발하여 수업 계획을 세워서 학습을 진행한다면 수업은 역동적이며 매우 흥미로워 질 것이다. 학생들은 말로 나타내기(Verbalization)와 상상(Imagination)의 충분한 경험을 바탕으로 정신적 표현(Mental representation)을 개발하여 수세기 기초를 확립하고 나아가 연산을 쉽게 수행할 수 있을 것이다. 여기에 소개된 교구들과 학습 활동들은 초등 수학 교육이 암기 위주의 문답식이 아니며 얼마나 역동적이고 흥미로울 수 있나를 보여준다.

• Journal of Educational Research in Mathematics
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• v.22 no.4
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• pp.619-636
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• 2012

The main purpose of this study was to explore the process of generalization generated by mathematically gifted students. Specifically, this study probed how fourth, fifth, and sixth graders might generalize geometric patterns and represent such generalization. The subjects of this study were a total of 30 students from gifted classes of one elementary school in Korea. The results of this study showed that on the question of the launch stage, students used a lot of recursive strategies that built mainly on a few specific numbers in the given pattern in order to decide the number of successive differences. On the question of the towards a working generalization stage, however, upper graders tend to use a contextual strategy of looking for a pattern or making an equation based on the given information. The more difficult task, more students used recursive strategies or concrete strategies such as drawing or skip-counting. On the question of the towards an explicit generalization stage, students tended to describe patterns linguistically. However, upper graders used more frequently algebraic representations (symbols or formulas) than lower graders did. This tendency was consistent with regard to the question of the towards a justification stage. This result implies that mathematically gifted students use similar strategies in the process of generalizing a geometric pattern but upper graders prefer to use algebraic representations to demonstrate their thinking process more concisely. As this study examines the strategies students use to generalize a geometric pattern, it can provoke discussion on what kinds of prompts may be useful to promote a generalization ability of gifted students and what sorts of teaching strategies are possible to move from linguistic representations to algebraic representations.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.333-339
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• 2013

In this study we investigated the relationship between characteristics of vegetative growth of three species of Viola (V. rossii, V. japonica, and V. dissecta var. chaerophylloides) and light in order to explain how these three species could live together under a closed space in a forest. This studywas carried out at five sites in Mudeung-san (Mt.) on 1994, 1995, and 2000 and additional investigations were performed on 2007 and 2010 at the same sites. In order to find the relationship, three main investigations were conducted: counting number of individuals for each investigated year, measuring dry mass and counting developed leaves per plant, and finding presenting patterns of each species with reference to incidence of light. As a result, we found that three species could share the closed space in a forest because of their different adaptive strategies like V. rossii as Kstrategist, V. japonica as r-strategist, and V. dissecta var. chaerophylloides as an intermediator between two species.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.238-246
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• 2016

The study aims to examine Japan's National REDD+ Strategies prepared for Post-2020 and the status of its implementation by organizations in Japan, and then to suggest the potential REDD+ countermeasures against Joint Credit Mechanism (JCM) for Republic of Korea and their implications. As for the technical limitations of the guidelines of REDD+ under the JCM, it is pointed out that forests located at the place with less potential safeguard intervention tend to be selected as the target area for a project and that, as reference emission trend changes depending on the basic year of the baseline, differences could occur among the amounts of greenhouse gas emission. In addition, it is pointed out that the result of the calculation of the displacement of emissions, or leakeage, in REDD+, can have an uncertainty, since the calculation is done by just multiplying leakage area by certain coefficients, without considering the size of the leakage area. Furthermore, the lack of implementation guideline or methodologies for a project level is also pointed out as a limitation, considering that there are only some national and sub-national monitoring guidelines at present. Finally, internationally accepted guidelines for safeguard and its sub-items needed to be prepared, as current safeguard policy only includes lists without detailed items. Such things mentioned above are all related to, and can lead to the problem of double counting of items in Nested Approach etc., as well as of the distribution of credits. Therefore, Republic of Korea should take these into consideration when implementing its REDD+ projects.

• Journal of Agricultural Extension & Community Development
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• v.11 no.1
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• pp.67-81
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• 2004

The objectives of this study were; a) to review the Ilgam Gatgi or a job project of the rural women b) to relate the vocational educational strategies for human resources development and c) to suggest appropriate vocational education programs for rural women in Korea. The study was carried out through literature reviews, and the results of the study were as follows : First, government should provide appropriate information and educational programs to support rural women for facilitating them to have a sound understanding of the Ilgam Gatgi project. Second, government should provide diverse vocational education programs to facilitate participation in the tasks such activities as for upbringing management mindness, counting and marketing abilities. Research and development works should be emphasized to develop further the traditional foods as well as new products. Third, national support activities should be reinforced to let the people recognize the Ilgam Gatgi projects and its products. and governmental supports should be made to establish cyber business transactions system for the products from the Ilgam Gatgi projects. Fourth education for the laws and regulations on manufacturing and marketing of processed foods would be necessary for rural women, since the majority of the products from the Ilgam Gatgi projects were processed foods.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.819-822
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• 2021

To enhance phage endolysin-mediated cell wall disruption of Escherichia coli O157:H7, the cells were co-treated with aromatic compounds, namely thymol or eugenol, found in essential oils and endolysin LysECP26. Interestingly, the minimal inhibitory concentrations of LysECP26 was four times lower when used in combination with either of the two compounds than when it was used alone. This synergistic activity was also confirmed by viable cell counting. Within 1 h of LysECP26 and eugenol or thymol co-treatment to the cells, there was a 2.3 or 3.8 log CFU/mL reductions, respectively. Additionally, field emission scanning electron microscopy showed cell wall disruption and severe morphological alterations of the cells in case of the combination treatments. Therefore, endolysin and thymol or eugenol co-treatment can help in developing efficient bio-control strategies against gram-negative pathogen E. coli O157:H7.

• Korean Journal of Radiology
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• v.25 no.1
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• pp.86-102
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• 2024

Early diagnosis, accurate assessment, and localization of peritoneal metastasis (PM) are essential for the selection of appropriate treatments and surgical guidance. However, available imaging modalities (computed tomography [CT], conventional magnetic resonance imaging [MRI], and 18fluorodeoxyglucose positron emission tomography [PET]/CT) have limitations. The advent of new imaging techniques and novel molecular imaging agents have revealed molecular processes in the tumor microenvironment as an application for the early diagnosis and assessment of PM as well as real-time guided surgical resection, which has changed clinical management. In contrast to clinical imaging, which is purely qualitative and subjective for interpreting macroscopic structures, radiomics and artificial intelligence (AI) capitalize on high-dimensional numerical data from images that may reflect tumor pathophysiology. A predictive model can be used to predict the occurrence, recurrence, and prognosis of PM, thereby avoiding unnecessary exploratory surgeries. This review summarizes the role and status of different imaging techniques, especially new imaging strategies such as spectral photon-counting CT, fibroblast activation protein inhibitor (FAPI) PET/CT, near-infrared fluorescence imaging, and PET/MRI, for early diagnosis, assessment of surgical indications, and recurrence monitoring in patients with PM. The clinical applications, limitations, and solutions for fluorescence imaging, radiomics, and AI are also discussed.

• East Asian mathematical journal
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• v.31 no.4
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• pp.505-525
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• 2015

The purpose of this study is to analyze teaching method of addition and subtraction of whole number in Korea and New Zealand lower grade textbook and to get some suggestive points to develop mathematics curriculum and for a qualitative improvement of textbook. To do this, we will analyze focusing on teaching material, type and method of teaching, cases of real teaching and in the case of New Zealand, we will analyze portfolios together to see what kind of things do they deal with related to addition and subtraction. From these analyzing, the results are as follows: First, the guideline of accomplishment of group of year are stated in 2009 revised curriculum in Korea but it is rough. On the other hand, the level of accomplishment from kindergarten to high school are stated divided by eight kinds of thing in New Zealand curriculum. Second, there were common and different points in the aspect of teaching material. The common points are that both of our Korea and New Zealand are using materials related to real life intimately and the diifferent points are to use technology such as calculator and computer. They are more widely used in New Zealand than our Korea. Third, Korea had used routine method mainly but New Zealand had used method to develop creativity of learner such as to write problem corresponding to expression, posing problem corresponding to information, to complete table and find pattern and to write word problem to explain pattern and so on. Fourth, we could see special calculation strategies in the case of teaching addition and subtraction such as concept of double, compensation, various strategy based on counting of number, addition of the same number, magic square, near-double which are not finding in our mathematics textbook. Fifth, in the New Zealand textbook they had used teaching methods inducing curiosity of learner such as finding message and puzzle problem than solving given problem simply.

• Journal of Educational Research in Mathematics
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• v.21 no.1
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• pp.67-86
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• 2011

This study aimed to examine first graders' recognition and thinking about mathematical patterns. To attain the goal, this paper analyzed 116 students' response with regard to repeating, growing, and changing patterns represented in both picture and number, and also analyzed four students' thinking process of the patterns through interview. It was found that students showed high recognition in repeating, growing, and changing patterns in order. Whereas there was no significant difference between picture and number representation in both repeating and growing patterns, pictures gained a bit higher scores than numbers in changing patterns. Also, according to the result of examining the thinking process by the patterns, students tended to consider the patterns as a bundle and tried to solve problems with counting strategies. The result of this paper provides an empirical foundation on how first graders recognize and think of various patterns.

• Animal cells and systems
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• v.3 no.1
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• pp.29-39
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• 1999

Current data on reproductive characters of endemic and native species are essential to provide a strategy for the conservation of these species. Red pine (Pinus densiflora Sieb. & Zucc.) is one of the dominant, native tree species in Korea, but its reproductive ecology is not well-known. In 1997, the pattern of variation in cone and seed yields contributing to the conservation of declining populations of red pines was examined. Plant height and dbh were measured, and several new cones were collected from each tagged tree after counting the number of cones on each tree. For a subset of cones sampled, the number of fertile scales, the number of seeds at three development stages (early/late aborted, and filled seed), seed wing size, wing color, and individual filled seed mass were measured. The three sites which differed significantly in mean plant size also differed in mean cone and seed production per plant. However further analyses showed that most variation in characters examined occurred among plants within sites, but not among sites. An average of 90% of the potential seeds on the cones aborted at an early developmental stage, demonstrating that early abortion is a major factor affecting the number of filled seeds per cone. Individual seed mass was the only character which exhibited significant variations among sites as well as among trees within sites. Individual seed mass was overall negatively correlated with both the percentage of late abortion and the number of old cones per plant, suggesting that both the past and current years' reproductive activities have caused variations in seed mass. The potential dispersal distance of red pine seeds is quite large. However, wing loading was correlated with seed mass and number in a complex pattern across the sites. Distribution of seeds with varied colored wings differed among sites and among trees within sites. These results suggest that red pines at different sites might possess different strategies to cope with selection pressures acting during the final phase of reproduction, from seed dispersal to establishment. Then the ‘fitted’ red pine trees at each site should be identified and managed to conserve or restore populations.