• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.40-59
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• 2018

This review summarizes the history of freshwater zooplankton research in Korean Society of Limnology and necessary future topics that are remain poorly investigated in South Korea based on main research topics of published articles focusing on lakes, reservoirs, rivers and wetland ecosystems. In Korea, a total 450 freshwater zooplankton species have been reported (85 species of cladocera, ca. 230 species of rotifera since 1939, and 138 species of copepoda), and they cover 10% of total zooplankton species list. In the present paper, we provide recent species list of zooplankton found in Korea and their taxonomic keys. Over periods of 45 years, there are 25 published papers for zooplankton biota in lentic ecosystems in Korean Journal of Ecology and Environment (KJEE). The ecology of zooplankton communities in rivers has focused on the mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns of genus Bosmina and rotifers (genus Brachionus and Keratella) that are most frequently found from Korea. On the other hand, the studies on zooplankton in wetland has focused on Alona, Chydorus and Ceriodaphnia with special emphasis on their relationships with aquatic macrophytes. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at rice paddy, Dumbeong and wetlands. During the last two decades, experimental advances in freshwater zooplankton ecology and understanding of structure and function of this biota were made from a series of articles mainly in journal of KJEE. For future studies, quantitative, experimental and interdisciplinary approaches would be key words to understand zooplankton ecology and their roles in aquatic ecosystems under changing environments, and we have suggested necessary zooplankton research fields and future directions.

• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.638-646
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• 2016

CWR (continuous welded rail) tracks on high-speed railway bridges have much more complicated axial force distributions caused by track-bridge interaction than those behaviors on embankments, and additional problems caused by track-structure interaction with the axial force of the CWR. In order to analyze and limit other physical phenomena caused by track-bridge interaction, a design guideline (KR C-08080, longitudinal track-bridge interaction analysis) is used when designing CWR track on bridges. Domestic analysis and design methods for track-bridge interaction follow the UIC 774-3R, and they suggest conservative methods and deterministic properties. Recently, many studies analyzing the methods of track-bridge interaction considering the loading history are being carried out; however, there has been insufficient studies of the variation of the resistance properties with a consideration of the actual loading history. In this study, the performances of rail fastening systems used for concrete track on bridges were tested and analyzed while considering the loading history. For this purpose, longitudinal and vertical loading combinations, applied in order to simulate the practical conditions and resistance characteristics (stiffness and elastic limit displacement), are analyzed through the experimental results. Also, a comparison study was conducted with the properties in the KR Code.

• ALGAE
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• v.31 no.2
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• pp.167-174
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• 2016

Biological response of cells to variable conditions should affect the expression level of certain genes. Quantification of these changes in target genes needs stable internal controls. Real-time quantitative polymerase chain reaction (PCR) has traditionally used reference or ‘housekeeping’ genes, that are considered to maintain equal expression in different conditions, to evaluate changes in target genes between samples and experimental conditions. Recent studies showed that some housekeeping genes may vary considerably in certain biological samples. This has not been evaluated in red algae. In order to identify the optimal internal controls for real-time PCR, we studied the expression of eleven commonly used housekeeping genes; elongation factor 1-alpha, glyceraldehyde-3-phosphate dehydrogenase, β-actin, polyubiquitin, 30S ribosomal gene, 60S ribosomal gene, beta-tubulin, alpha-tubulin, translation initiation factor, ubiquitin-conjugating enzyme, and isocitrate dehydrogenase in different life-history stages of Bostrychia moritziana. Our results suggest that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 30S ribosomal gene, have the most stable gene expression levels between the different life history stages (male, female, carposporophyte, and tetrasporophyte), while the other genes are not satisfactory as internal controls. These results suggest that the combinations of GAPDH and 30S would be useful as internal controls to assess expression level changes in genes that may control different physiological processes in this organism or that may change in different life history stages. These results may also be useful in other red algal systems.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06b
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• pp.129-140
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• 1998

There is considerable research activity related to computer graphics and virtual reality within the National Chiao Tung University (NCTU), Hsinchu, Taiwan. In this article, we describe the history of computer graphics at NCTU and report on our current research topics and future works. Besides we also briefly outline the research works on computer graphics and virtual reality within universities in Taiwan.

• Mycobiology
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• v.45 no.4
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• pp.338-343
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• 2017

Cryptothecia austrocoreana is a new lichen species from South Korea. The species is characterized by the presence of a heteromerous thallus and faveolate ascigerous area (ascomata) immersed in a slightly raised thallus. The species has muriform ascospores, (4)6-8-spored $8-11{\times}3-4$ septate, $(34)36-48(51){\times}(17)19-23(25){\mu}m$. Atranorin, chloroatranorin, and barbatic acid are present. In the phylogenetic tree, C. austrocoreana belongs to the arthonioid clade in Arthoniaceae.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.499-510
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• 2019

History and philosophy of science has been consistently emphasized in science education for various purposes. In accordance with the introduction of the 2015 revised curriculum, history of science could be implemented for the curriculum; designing well-organized learning strategies is required. This study examines the case of undergraduate students who solved the convergence problem based on history and philosophy of science in the problem-based learning program. In particular, this study tries to find strategies for integrated education by comparing the problem structuring process and the meaning of problem solving experience of science/engineering and humanities/social sciences students. Participants were three students majoring in science/engineering and humanities/social sciences. Participants constructed and solved their own convergence problems by integrating the domains that were familiar to them into history and philosophy of science. While the process of structuring the problems and the use of history and philosophy of science were similar, there were differences between the science/engineering and humanities/social sciences students' point of view on history and philosophy of science and the other domain which they choose. Moreover, there were differences between the two group's meanings of problem solving experience. Finally, based on the results of this study, history and philosophy in science provided some implications in the context of science education and integrated education.

• Journal of Broadcast Engineering
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• v.22 no.4
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• pp.429-437
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• 2017

2D-to-3D conversion technology has been studied over past decades and integrated to commercial 3D displays and 3DTVs. Generally, depth cues extracted from a static image is used for generating a depth map followed by DIBR (Depth Image Based Rendering) for producing a stereoscopic image. Further, motion is also an important cue for depth estimation and is estimated by block-based motion estimation, optical flow and so forth. This papers proposes a new method for motion depth generation using Motion History Image (MHI) and evaluates the feasiblity of the MHI utilization. In the experiments, the proposed method was performed on eight video clips with a variety of motion classes. From a qualitative test on motion depth maps as well as the comparison of the processing time, we validated the feasibility of the proposed method.

• Journal of Species Research
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• v.3 no.2
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• pp.183-194
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• 2014

As part of a study to understand the current status of Korean plant species propagated in foreign countries, we conducted extensive surveys on Korean living collections in the Arnold Arboretum of Harvard University, the oldest public arboretum in North America. Specifically, we collected and identified the voucher specimens of the living collections and further examined the collection databases to understand the history of how Korean plants were introduced to the Arboretum. We found that a total of 154 Korean taxa (belonging to 49 families and 81 genera) have been planted in the arboretum. Most plants originated from seeds that were directly collected in Korea or obtained via seed exchanges with botanical gardens in Asia, Europe, and U.S.A. Of the 154 taxa, 16 are Korean endemic species, and three are listed as endangered species. In addition, 62 taxa are as floristic regional indicator species of Korea used by the Ministry of Environment.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.11a
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• pp.142-143
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• 2016

본 논문에서는 애니메이션, 드라마, 영화 등 영상으로 제작된 콘텐츠를 OpenGL를 사용하여 3D영상으로 재구성한다. 먼저 현재영상과 이전영상의 움직임의 차이로부터 운동 축적 데이터를 사용하여 모션 깊이맵을 생성한다. 그 깊이맵을 사용하여 OpenGL에서 사용하는 텍스쳐 맵핑으로 영상을 출력하고 3D 영상을 구현하기 위해 좌영상과 우영상을 생성하여 3D 입체영상을 만든다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.11a
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• pp.146-147
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• 2016

손동작 인식은 대부분 스킨 컬러 검출을 이용하였다. 하지만 이와 같은 방법으로는 빛이나 주변 사물에 의해 영향을 많이 받기 때문에 정확한 값을 일정하게 도출 해낼 수 없었다. 이에 본 논문은 운동축적 기법을 이용하여 움직임을 파악한 후 손의 움직임을 트랙킹하여 운동 방향을 구한다. 제안된 시스템은 C/C++을 기반으로 구현하여, 실험에서 제안 방법이 안정적이고 우수한 성능을 보여줌을 증명하였다.