• The Korean Journal of Mycology
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• v.37 no.1
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• pp.117-119
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• 2009

Rhizopus soft rot caused by Rhizopus stolonifer occurred on strawberry (Fragaria ${\times}$ ananassa) in the plastic boxes in Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea on April 2008. The infected fruits were rapidly softened, water soaked and finally rotted. The symptoms were mainly occurred through wounds at harvest time. The colony color was white, cottony to brownish black after fully matured and numerous sporangiospores were formed on sporangia. The optimum growth temperature of the fungus was $30^{\circ}C$ on potato dextrose agar. Sporangia were globose or hemispheric shape of white color at initial stage and gradually changed with black color of $82{\sim}195{\mu}m$ in size. Sporangiophores were $12{\sim}25{\mu}m$ in width. Columella were hemispheric in shape, and $70{\sim}92{\mu}m$ in size. Sporangiospores were irregular round or oval in shape, brownish-black in color and $9{\sim}21\;{\times}\;7{\sim}8{\mu}m$ in size. This fungus formed stolones and rhizoid on PDA. On the basis of symptom, mycological characteristics and pathogenicity of the fungus, the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill.

• Research in Plant Disease
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• v.14 no.1
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• pp.57-60
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• 2008

A rhizopus soft rot caused by Rhizopus stolonifer occurred sporadically on apple fruits (Malus pumila var. dulcissima Koidz.) at a wholesale market of agricultural products in Jinju, Korea in 2006 and 2007. Infected fruits were rapidly water-soaked, softened and rotted. The symptoms were initiated mainly from wounds or cracks occurred at harvest time. Sporangiophores were $950{\sim}1,900\;{\mu}m$ in length and $12{\sim}22\;{\mu}m$ in width. Sporangia were globose or hemispheric and $82{\sim}185\;{\mu}m$ in size. The color of sporangia was white and cottony at first and gradually turned to brownish black, bearing abundant spores when matured. Columella were hemispheric and $70{\sim}85\;{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $8{\sim}18{\times}7{\sim}8\;{\mu}m$ in size. Optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. On the basis of mycological characteristics and pathogenicity to apple the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill. This is the first report of Rhizopus soft rot by R. stolonifer on Fuji apple in Korea.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.4
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• pp.56-61
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• 2009

This paper presents the ground surface potential profiles and hazard voltages around the metallic structure connected to a small-sized model ground electrode. Because it is very difficult to draw valid conclusions concerning a general grounding problem from actual field data, scale model tests can be used to determine the touch and stop voltages and surface potential profiles around ground electrode. In this work, a hemispherical vessel with a diameter of 1,100[mm] was employed to simulate uniform soil. As a result, the ground surface potential around the ground electrode was significantly raised In particular the ground surface potential at the just upper point of ground rod was higher than other points. When the buried depth of ground rod is increased, the ground surface potential and step voltage were lowered but the touch voltage was elevated.

• Korean Journal of Plant Taxonomy
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• v.47 no.4
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• pp.308-315
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• 2017

A new species, Corydalis bonghwaensis M. Kim & H. Jo, is described here. It is found on a mountain slope in Bongwha-gun, Gyeongsangbuk-do, Korea. Corydalis bonghwaensis shares several characteristics (white flowers, glabrous pedicels, white tubers, and the polygonal stigma) with related species C. namdoensis B. U. Oh & J. G. Kim and C. albipetala B. U. Oh. However, this new species has flowers which change from pale-yellow to white, a mucronated inner-petal apex, linear leaflets, and fusiform capsules with two-rowed seeds. In contrast, C. namdoensis has retuse inner-petal apex, various leaflets, and fusiform capsules with 2-rowed seeds. C. albipetala has retuse inner-petal apex, elliptical leaflets, and linear capsule with 1-rowed seeds. Also C. humilis B. U. Oh & Y. S. Kim has pale-blue purple flowers, elliptical leaflets, inflorescence with 1-5 flowers, and hemispherical lower-outer petal.

• Composites Research
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• v.33 no.4
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• pp.205-212
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• 2020

In this study, HfC was coated on two types of carbon/carbon composites coated with SiC by vacuum plasma spraying(VPS). The experiment was performed using a plasma wind tunnel with heat flux of 5.06 MW/㎡ for 120 s heat flux before and after the coating. The mass ablation rate was calculated through the mass change before and after the test, and the length change was measured by using calipers and high speed camera. The oxidation/ablation behavior were observed by FE-SEM with EDS analysis of the specimens cross section. The plasma wind tunnel test results showed that the coated specimens had low weight loss and length change, and high oxidation/ablation resistance. However, two types of the specimens tested under the same conditions were different in the ablation behavior and ablation rate, and it was evaluated that the cylindrical type had higher oxidation/ablation resistance.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.5
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• pp.405-414
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• 2015

Fluid transport is a key issue in the development of microfluidic systems. Recently, Myong (2014) has proposed a new concept for droplet transport without external power sources and numerically validated the results for a hypothetical 2D, initially having a hemicylindrical droplet. In this paper, the movement of an actual water droplet, initially having a 3D hemispherical shape, on horizontal hydrophilic/hydrophobic surfaces is simulated using a commercial computational fluid dynamics (CFD) package, Fluent, with VOF (volume of fluid) method. The results are compared with the 2D analysis of Myong (2014), and the transport mechanism for the actual water droplet is examined based on the numerical results of the time evolution of the droplet shape, as well as the total kinetic, gravitational, surface free and pressure energies inside the droplet.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.133-135
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• 2001

데이터로서 XML 역할에 대한 중요성이 증대되어감에 따라, 구조 정보를 내포하고 있는 데이터로서의 XML 문서를 효과적으로 관리하는 구조설계 및 질의어 처리에 대한 연구가 활발히 진행되고 있다. XML 저장구조는 XML 스키마에 의존하지 안고, 반구조적 데이터에 대한 저장과 질의처리 설계방법과 DTD와 같은 XML 스키마를 기반으로 저장구조를 설계하는 방법이 있다. DTD는 XML 문서의 논리적인 구조정보를 표현하는 역할을 가지고 있으며, 그러한 역할은 이 기종간의 문서교환시 더욱 중요해진다. DTD 기반의 XML문서를 관계형 테이블로 사상하고자 할 때, 사상과정이 자동적으로 이루어지는 경우와 사용자가 관리자가 직접 테이블 생성에 관여하는 수동적인 사상방법이 있다. 수동적인 사상과정은 질의처리가 구현시 데이터베이스 설계 방법에 크게 의존하게 되는 단점이 있지만, 사용자가 주어진 DTD 구조에 따라서 특정 응용에 알맞은 저장구조를 직접 설계하기 때문에 더 효율적인 저장구조를 설계할 수 있다. 본 논문에서는 관계형 DB를 질의처리 하기 위한 하부 저장소로 사용하고, DTD 기반의 XML 문서를 관계형 DB 테이블간의 수동적인 사상과정을 통하여 효율적인 XML 문서 저장구조를 설계하는 방법을 제시한다.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.805-813
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• 2004

Our educational system clearly places much greater value on left hemisphere learning. Students who process information in other ways are at a serious disadvantage and may not be learning efficiently. Since mind mapping emphasizing visual and spatial language, it helps students to use the whole brain and promotes more effective comprehension. The purpose of this research was to determine the effects of the instruction using mind map on the science achievement of students. A pretest-posttest control group design was employed. Subjects were 153 male and female, first grade students in a middle school. A control group of 83 was instructed with a traditional teaching method, and an experimental group of 70 was instructed by using a mind mapping strategy. Two groups were treated for 50 hours during 17 weeks. Tolerance's 'Style Of Learning And Thinking(SOLAT)' was used to assess students' lateralization preferences. A 30-item multiple choice posttest was used to assess students' achievement. To analyze the data, we used an analysis of covariance(ANCOVA) and i-tests. It was found that 21.6% of students was left brain dominant, 31.4%, right brain dominant and 47.1 % was integrated style. There was no gender difference in hemispheric dominance. Significant differences existed between the test scores when they were taught by using a mind map. Mind mapping turned out to be a valuable learning technique for the right brain students, helping them to achieve the same level of subject mastery as left brain students. There was a significant difference between males and females in relation to mind map application. Female scored significantly higher than males.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.591-601
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• 2024

As generative AI-based educational content and services targeting child users rapidly increase, the need for research related to children's perception of generative AI is increasing. Accordingly, this study sought to determine the type of generative AI recognized by children and whether cognitive, behavioral, and emotional properties were assigned to it. To understand this, we collected responses through workshop activities to create storybooks with children, semi-structured interviews, and drawing. As a result, children viewed generative AI as an artifact with a high cognitive level, but it was not a type of existing artifact.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.22-24
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• 2004

XML은 관계형 데이터는 물론 구조화 또는 반구조화 된 데이터를 효과적으로 조직화하여 표현할 수가 있다. XQuery는 구조화된 XML 데이터를 대상으로 필요한 정보를 검색하는 질의어이다. 평면적인 테이블 형태의 SQL과는 달리 XQuery는 데이터의 내부구조 정보 없이는 질의어를 작성하는데 어려움이 따른다. 이 논문은 내부적으로 구조화된 XML데이터에서 필요한 정보를 검색하는 검색언어 XQuery질의를 효과적으로 작성할 수 있도록 질의 대상이 되는 XML 데이터 구조를 트리 형태로 보여주고, 필요한 경로식을 효과적으로 지정함으로써 질의어를 보다 쉽게 작성하도록 도와주는 XQuery 작성기를 설계하고 구현한다.