• Title/Summary/Keyword: 별형성

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A Study on the History of Chinese Roadside Tree through Old Literatures Review (고문헌 고찰을 통한 중국 가로수의 역사에 대한 연구)

  • Zhong, Tao;Ahn, Gye-Bog
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.1-10
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    • 2018
  • For a systematic research of the history of Chinese roadside trees, this study analyzed various ancient writings of China according to following topics; the philosophical backgrounds and diverse species of Chinese roadside trees in different periods, as well as the management systems and existent remains of ancient Chinese roadside trees. The analyses draw the following conclusion. First, the thoughts from Lao-tzu, Chuang-tzu, Mo-tzu, Mencius and Guan-tzu from Hundred Schools of Thought of Warring States Period had laid certain impact on the fundamental attitude of the Chinese roadside tree management system. Secondly, various and different species of Roadside Trees were planted from each time period: amongst all, Willow trees were the most common, and Pine trees to be the next common. Besides, fruit trees such as peach trees and plum trees had been largely selected as roadside trees from the Zhou dynasty to the Ming dynasty. Thirdly, the names of roadside trees and the government officials who managed the roadside trees were different in each era. Fourthly, the oldest existent remain of roadside trees in China, which dates back over 2000 years, is located in Jiange Cuiyun Corridor of Sichuan province.

Identification of Virus from Azuki Bean Plant (팥에 발생하는 바이러스 분리 동정)

  • 허남기;강문석;하건수;김혜자;최장경
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.2
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    • pp.160-165
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    • 1997
  • Three types of virus disease symptoms were observed in azuki bean plants: yellow mosaic; mosaic; severe mosaic with dwarf. The symptoms developed in the indicator plant inoculated with a virus- infected leaf of azuki bean showed similar host range with those of AMV, CMV and AzMV. In antiserum response, yellow mosaic symptom formed sediments with AMV antiserum, mosaic type with CMV antiserum, respectively, From the electron microscope observation, eclliptic particle (18~58$\times$18nm), isometric particle (30nm), and filamentous(730$\times$12nm) combined with inclusion body were observed in yellow mosaic, mosaic, and severe mosaic with leaf curling symptoms, respectively, The results demonstrate that yellow mosaic, mosaic, and severe mosaic with dwarf are caused by AMV, CMV and AzMV.

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A Study on the Analysis of Intellectual Structure of Korean Veterinary Sciences (국내 수의과학 분야의 지적 구조 분석에 관한 연구)

  • Cho, Hyun-Yang
    • Journal of Information Management
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    • v.43 no.2
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    • pp.43-66
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    • 2012
  • The purpose of this study is to see the intellectual structure in the field of veterinary sciences in Korea, using author profiling analysis(APA), a bibliometric approach. Three journals are selected on the basis of citation data, exchanging most citations with Korean Journal of Veterinary. And then, 50 authors who published most articles at selected journals during the given period of time were chosen. The analysis of similarity and dissimilarity among authors by comparing co-word appearance patterns from article title, abstracts, and keywords was made. Authors can be grouped 11 minor clusters under 4 major clusters, depending on their interests in the area of veterinary sciences in Korea. The subjects for each cluster at the veterinary sciences are decided by the matching the keyword, representing author's research interest. As a result, it is possible to figure out the current research trends and the researcher network in the field of veterinary sciences.

Studies on the Ecology of the pine Gall-Midge (Thecodiplosis japonesis Uchida et Inouye) II -The summer Felling period and Distribution of infested degrees (솔잎 혹파리의 생태조사(生態調査) (2) -하기벌채시기(夏期伐採時期)와 피해분포(被害分布)-)

  • Ko, Je Ho
    • Journal of Korean Society of Forest Science
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    • v.7 no.1
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    • pp.40-44
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    • 1968
  • 1. The larvae of the pine gall-midge begin to grow slowly from early July but grow rapidly from September. 2. The number of larvae in the galls does not decrease during the feeding period. 3. Pine needles infested by pine gall-midge cease to grow as soon as the gall starts to form. 4. In Seoul district the effective felling season of the pine trees for the Control of the pine gall-midge seems to be around 20th September when the size of larvae reaches 1.4-1.5mm in length. 5. The stratification and direction of the Crown, and the length of new shoot had no effect on the degree of infestation by pine gall-midge. However the degree of infestation differed among the trees of different ages as well as at the different levels of the mountain.

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Morphology and Characteristics of Floral Organ in Highbush Blueberry (Vaccinium corymbosum) Cultivars (하이부쉬 블루베리의 품종별 화기 특성 및 형태적 관찰)

  • Kim, Su Jin;Bae, Kang Soon;Koh, Sang-Wook;Kim, Ho Cheol;Kim, Tae-Choon
    • Korean Journal of Plant Resources
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    • v.28 no.2
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    • pp.235-242
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    • 2015
  • Morphology and characteristics of floral organ in highbush blueberry cultivars were studied to select suitable cultivars of highbush blueberry for domestic cultivation. The stamen consists an anther and a tape-like hairy filament with well-developed trichomes. When the anther was opened, the wall of anther was not dehiscent, and pollen grains were discharged into two tubes. Pollen was mature tetrad type without being separated after meiosis (Late March). The number of pollen granules per anther was 400~1,300, the germination rate was higher in the cultivars having many pollen grains. Pistil was composed of five carpels and a shipper without separate part. The number of ovules per ovary was 39~67, therefore, the coefficient of ranged from 11.6 to 31.0%. The seed pod formation by combination of ‘Bluejay’ and ‘Sharpblue’ was higher in the cross-pollination than in the self-pollination.

Performance analysis of sensor selection methods for beam steering direction of non-linear conformal array (비선형 곡면 배열 센서의 빔 지향 방위별 센서 선택 방법에 대한 성능 분석)

  • Kwon, Taek-ik
    • The Journal of the Acoustical Society of Korea
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    • v.40 no.4
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    • pp.391-399
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    • 2021
  • The conformal array sensor has different sub-array depending on different beam steering directions. According to the method to effective the sensor, the performance of the conformal array sensor can be different, where the sub-array selects an effective sensor. Also, due to the figure of the conformal array sensor, the figure of the sub-array can be different each other, which results in different performance on directivity index, beam width and etc. In this paper, two methods to select sub-array which is the criteria for each sensors position vector and directive vector were proposed. For two sub-array selection methods, the performance of the directivity index, horizontal and vertical beam width were compared with the average and variance. In addition, this comparison was conducted when the number of sensors was fixed. When the number of sensors was not fixed, the directional vector method mainly results in high performance, but the performance of vertical beam width was lower or equal. When the number of sensors was fixed, the performance of two methods is similar, but the performance of variance was deteriorated.

An Exploratory Study of VR Technology using Patents and News Articles (특허와 뉴스 기사를 이용한 가상현실 기술에 관한 탐색적 연구)

  • Kim, Sungbum
    • Journal of Digital Convergence
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    • v.16 no.11
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    • pp.185-199
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    • 2018
  • The purpose of this study is to derive the core technologies of VR using patent analysis and to explore the direction of social and public interest in VR using news analysis. In Study 1, we derived keywords using the frequency of words in patent texts, and we compared by company, year, and technical classification. Netminer, a network analysis program, was used to analyze the IPC codes of patents. In Study 2, we analyzed news articles using T-LAB program. TF-IDF was used as a keyword selection method and chi-square and association index algorithms were used to extract the words most relevant to VR. Through this study, we confirmed that VR is a fusion technology including optics, head mounted display (HMD), data analysis, electric and electronic technology, and found that optical technology is the central technology among the technologies currently being developed. In addition, through news articles, we found that the society and the public are interested in the formation and growth of VR suppliers and markets, and VR should be developed on the basis of user experience.

A study on Motivation Factors and User Responses of Mods for PC Game and its Influences to Continuance Intention - Focusing on - (게임의 모드 이용 동기별 사용자 반응이 지속 사용 의도에 미치는 영향에 대한 연구)

  • Choi, Won-Bin;Chang, Byeng-Hee
    • Journal of Korea Game Society
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    • v.21 no.4
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    • pp.25-42
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    • 2021
  • This study investigated motivation factors of mods and their influence on user response to analyze IS Continuance. The data of 610 players of who used mods was analyzed by a Post Acceptance Model of IS Continuance, followed by empirical results. As a result of SEM, the motive factor was divided into the 'Media characteristic', 'Content characteristic', and 'Situational characteristic'. The motive factors significantly affected user response of 'Perceived Usefulness', 'Satisfaction', and 'IS Continuance'; each motivation factors have different influence and 'Content characteristic' significantly affected the IS Continuance.

Numerical Simulation of Changes on Mixed Layer Depth with Climate Variability : SCHISM model (기후변동성을 고려한 연안해역의 혼합층 두께 변화양상 검토: SCHISM 적용)

  • Yoo, Hyung Ju;Lee, Joon-Soo;Kim, Dong Hyun;Lee, Seung Oh
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.273-273
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    • 2022
  • 혼합층(Mixed layer)은 온도가 일정한 수심층으로, 해수표면에 작용하는 바람의 영향으로 인하여 해수가 위아래로 섞여 형성된다. 이러한 혼합층은 영양염의 순환과 산소의 공급 등과 함께 일차생산량을 결정하는 중요한 요인이 될 수 있으며 혼합층 두께의 변동은 양식 산업에 영향을 미칠 수 있다. 최근에는 기후변화로 인한 해수면 상승 및 해수온 상승 등이 지속되고 있으며, 이러한 현상은 해양생태계의 변화를 초래하여 수산업의 피해를 유발할 수 있다(강원연구원, 2017). 이에 국립수산과학원, 기상청, 국립해양조사원 등 유관기관에서는 정선해양 수온 관측 및 해수순환모델을 이용하여 혼합층의 분석을 수행하고 있으나 격자 구축 및 초기·경계장 설정의 한계가 존재하여 정밀하고 정확한 혼합층 분석에는 어려움이 있다. 이에 본 연구에서는 비정형격자를 사용하여 격자 구축에 제약이 없는 SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model)을 이용하여 우리나라 연안해역의 계절변화 및 기후변동성에 따른 혼합층 두께의 변화를 검토하고자 한다. 연구대상지는 서해·동해·남해를 포함한 우리나라 전체 연안 해역(위도: 32°N ~ 39°N, 경도: 124°E ~ 132°E)으로 선정하였으며, 격자크기 100 ~ 3,000 m인 삼각격자로 격자를 구축하였다. 혼합층을 분석하기 위하여 수직격자 층은 50층으로 SZ(Sigma Z coordinate system)좌표계를 사용하였다. 초기·경계장은 FES(Finite Element Solution)2014, HYCOM(Hybrid Coordinate Ocean Model) 및 대기모델 결과를 이용하여 설정하였다. 수치모형 검증을 위하여 수온관측소에서 수심별 측정한 수온 값과 SCHISM 결과 값을 비교하였고, 상대오차가 약 10% 이내로 나타나 모형의 정확도를 확인하였다. 최종적으로 해수면 상승 및 해수온 상승 시나리오를 고려하여 계절별 연안해역의 혼합층 두께의 변화 양상에 대하여 검토하였다. 향후에는 보다 정밀한 대기모델과의 혼합모형 구축 및 다양한 수심 별 관측자료를 활용한다면 실무에서 적용 가능한 혼합층 분석 및 수산업 피해 발생 지역에 대한 피해저감 대책 수립이 가능할 것으로 판단된다.

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Callus Initiation and Organ Formation from in vitro Culture of Pelargonium spp. (In Vitro Culture에 의한 Pelargonium spp.의 Callus 유도 및 기관분화에 관하여)

  • Lee, Chun-Ha;Chung, Hae-Joon
    • The Journal of Natural Sciences
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    • v.4
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    • pp.143-159
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    • 1991
  • In order to investigate the micropropagation of Pelargonium, 2 cultivars of P. peltatum 'Pouletta' and P. zonale 'Pinto Red' were cultured in vitro on the MS basal medium supplemented with various concentrations of growth regulators. It attempted to study the induction of callus and the differentiation of organs from leaf disc, petiole segments, stem segments. hypocotyle segments and flower stalk segments. The results are summarized as follows; A. As for the initiation of callus, stem explant was proved to be the most suitable one among various explants of P. zonale 'Pinto Red'. The medium was supplemented with 1.0mg/1 BAP and 1.0mg/1 NAA. As NAA concentration increased, callus formation was enhanced, but higher concentration of NAA inhibited callus fromation. Leaf and hypocotyle explants showed less callus formation than stem and petiole explants. B. In P. zonale 'Pinto Red' petiole culture, the condition of cullus culture such as hormone concentration resulted in affecting shoots differentiation. The best result of shoots formation from the callus reculture were obtained from the combination of 0.5-1.0mg/1 BAP and 0.1-1.0mg/1 NAA when the callus was cultured in 1.0mg/1 BAP and 0.05mg/1 NAA. When the callus was cultured in medium without BAP, the shoot was not differentiated in subculture regardless to BAP and NAA concentration. and only callus was formed. C. Poly-phenol substance was observed in MS medium supplemented without PVP, in which callus was not formed from the leaf of P. peltatum 'Rouletta'. Polyphenol substance was not observed in MS medium supplemented with PVP, in which callus formation was increased. D. The callus formation of P. peltatum 'Rouletta' showed the stem explant being best result. The best result particularly in the stem explant among others. The optimal hormonal concentration was 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot formation was observed at 0.05mg/1 NAA and 1.0mg/1 BAP, 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot was malformed and the tissue recultured turned necrotic.

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