• Title/Summary/Keyword: 초기 중심

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Evaluation of Structural and Functional Changes of Ecological Networks by Land Use Change in a Wetlandscape (토지이용변화에 따른 거시적 습지경관에서의 생태네트워크의 구조 및 기능적 변화 평가)

  • Kim, Bin;Park, Jeryang
    • Ecology and Resilient Infrastructure
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    • v.7 no.3
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    • pp.189-198
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    • 2020
  • Wetlands, which provide various ecological services, have been regarded as an important nature-based solution for, for example, sustainable water quality improvement and buffering of impacts from climate change. Although the importance of conserving wetlands to reduce the impacts of various perturbations (e.g., changes of land use, climate, and hydrology) has been acknowledged, the possibility of applying these efforts as a nature-based solution in a macro-scale (e.g., landscape) has been insufficient. In this study, we examine the possibility of ecological network analysis that provides an engineering solution as a nature-based solution. Specifically, we analyzed how land use change affects the structural and functional characteristics (connectivity, network efficiency, and clustering coefficient) of the ecological networks by using the ecological networks generated by multiple dispersal models of the hypothetical inhabiting species in wetlandscape. Changes in ecological network characteristics were analyzed through simultaneously removing wetlands, with two initial conditions for surface area, in the zones where land use change occurs. We set a total number of four zones of land use change with different wetland densities. All analyses showed that mean degree and network efficiency were significantly reduced when wetlands in the zones with high wetland density were removed, and this phenomenon was intensified especially when zones contained hubs (nodes with high degree). On the other hand, we observed the clustering coefficient to increase. We suggest our approach for assessing the impacts of land use change on ecological networks, and with additional analysis on betweenness centrality, we expect it can provide a nature-based engineering solution for creating alternative wetlands.

Morphological Study of the Regeneration of the Mouse Olfactory Epithelial Cells after Destruction by Intranasal Zinc Sulfate Irrigation (코 안 $ZnSO_4$ 점적으로 손상된 마우스 후각 상피세포의 재생에 대한 형태학적 연구)

  • Kang, Wha-Sun;Moon, Young-Wha
    • Applied Microscopy
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    • v.37 no.4
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    • pp.219-230
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    • 2007
  • The morphological effects of intranasal zinc sulfate(5% solution) irrigation on the mouse olfactory epithelium and the regeneration process of olfactory receptor cells following nasal irrigation were studied with scanning and transmission electron microscope. The results were as follows: 1. The septal epithelium except some basal cells was wholly detached from the basement membrane, during the first 6 to 24 hours after 5% zinc sulfate irrigation. 2. 3 days after $ZnSO_4$ treatment, two layered septal epithelium was formed from basal cells. And microvilli were observed in the apical epithelium of newly formed olfactory epithelial cells. 3. 5 days after treatment, a lot of centrosomes and basal bodies were observed in the olfactory receptor cells, and cilia were lined up between microvilli on the apical membrane of olfactory receptor cells. And immature olfactory knob was first observed in the newly formed olfactory receptor cells. Mature olfactory knob was observed 1 week after treatment. 4. There are very many mature olfactory knobs in the olfactory receptor cells 2 weeks after intranasal zinc sulfate irrigation. These results support that treatment with 5% zinc sulfate is a good experimental model for the regeneration of mammalian nervous tissues because this method could thoroughly detach the septal epithelium. During the regeneration of olfactory receptor cells, the surface membrane of the olfactory receptor cells widen the surface with the microvilli. Then cilia, which arranged in a line, substituted for the microvilli. The part of the surface membrane with cilia protruded and finally formed the olfactory vesicle.

배양액이 마우스 핵이식 재구축배의 초기발생에 미치는 영향

  • 심보웅;권오용;이은화;김순희;서정선
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.76-76
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    • 2002
  • 본 실험은 Piezo-미세조작기(PrimeTech Ltd., Japan)를 사용하여 마우스 핵이식 후 재구축배를 CZB와 KSOM 두가지 배양액을 사용하여 체외배양성적을 비교 검토하였다. MII의 미수정란은 성숙한 4~5주령 B6D2Fl에 hCG 주사 후 14시간째에 과적 방법을 통해 난관의 팽대부로 부터 회수하였고, metaphase II chromosome-spindle complex와 최소량의 세포질을 내경이 10$\mu\textrm{m}$인 피펫으로 흡입하여 탈핵하였다. 핵이식에 사용된 난구세포(8-l0$\mu\textrm{m}$)는 3시간동안 12% PVP 에처리 하여 piezo-미세조작기를 이용하여 세포질에 세포의 핵을 직접 미세주입 하였다. 핵이식 후 생존한 재구축배는 2시간동안 배양한 후 10mM SrC1$_2$와 5$\mu\textrm{g}$/$m\ell$의 cytochalasin B가 첨가된 $Ca^{2+}$-free CZB에서 6시간 활성화 처리하였다, 활성화 처리 후 위전핵이 관찰된 재구축란을 CZB 와 KSOM 배지에서 배양하면서 발달률을 비교하였고, 상실배 및 배반포배로 발달한 재구축배를 day 3 대리모에 이식하였다. 표 1에서 보는 바와 같이 재구축배의 2-cell로의 발달률에 있어서 KSOM이 CZB에 비하여 유의적으로 높게 나타났으며(P<0.05), 또한 4-cell과 상실배/배반 포배로의 발달률에 있어서도 KSOM이 CZB에 비하여 유의적으로 높은 발달률을 나타내었다(P<0.01). 또한 KSOM 배지에서 배양된 상실배/배반포배를 대리모에 이식한 경우에 11.5 d.p.c에 생존한 태아가 관찰되었다. 이상의 결과로 핵이식 재구축배의 활성화 처리 후의 발생에는 KSOM 배지가 CZB 배지에 비하여 유효함을 확인 할 수 있었다.그와 같은 배양 기술을 이용하여 외래유전자를 도입한 일련의 결과에 관하여 보고 하고자한다., 이것은 세포내 유전자가 transfection되지 않은 세포도 neo selection에서 선발된다는 것을 제시하고 있다. 따라서 체세포를 이용한 형질전환동물 생산을 위해서는 세포내 유전자 도입과 선발 과정에서 나타난 colony에 대하여 보다 엄격한 screen을 하는 것이 필요한 것으로 생각된다.로 우점하였다. 여름철 식물플랑크톤 대발생에 영향은 수온과 직산염이 중요하였으나, 부유물질 크게 기여하지 못하였다.애를 확인하고 지도 관점을 파악하는 것을 포함한다. 그러나 본 논문은 역사발생적 수학 학습-지도 원리의 실제적인 적용에 관하여는 기초적인 연구에 지나지 않기 때문에, 역사발생적 원리를 학교수학에 실제적으로 적용하기 위해서는 각각의 내용에 대한 철저한 역사적 분석을 바탕으로 하는 후속 연구가 필요하다./TEX>구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to look into the origin of the letter designs in t

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Occurrence of Jujube Witches' Broom Disease and Control Efficacy of Trunk Injection with Oxytetracycline in Boeun Area from 2018 to 2019 (2018-2019년 보은지역 대추나무 빗자루병 발생 및 옥시테트라사이클린 수간주사 방제 효과)

  • Kang, Hyo-Jung;Choe, Seonghui;Lee, Kyeong Hee;Park, Heesoon;Oh, Ha Kyung;Lee, Seongkyun;Shin, Hyunman
    • Research in Plant Disease
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    • v.26 no.1
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    • pp.19-28
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    • 2020
  • Jujube witches' broom (JWB) disease is a high-risk plant disease that occurred on and devastated jujube orchards throughout South Korea in the 1950s. Recently, as the jujube cultivation area has been significantly increased nationwide, we investigated the disease in jujube orchards in the Boeun region to obtain basic information for proactively evaluating the risk of JWB outbreaks from 2017 to 2019. A field trial was conducted to evaluate the effect of the trunk injection of Sungbocycline (a. i. oxytetracycline calcium alkyl trimethyl ammonium 17%, OTC). The incidence of JWB disease was very low in Boeun, but it was gradually increased mainly in the area and on the farms where it had occurred previously. The trunk injection with OTC was most effective in the early stages of growth. However, even though the trees were treated with OTC, disease symptoms appeared in other healthy branches in severely affected trees. When the tree was first injected with OTC in June, the control efficacy of second injection was higher one month after the first injection than five months. These results suggest that early diagnosis based on various symptoms and early control based on them can be very effective in preventing JWB disease in advance and increasing control efficacy.

Development and Application of Subway's Operating Cost Functions with Full Allocation Method (For Seoul, Incheon, Busan and Daegu) (완전배정방법을 이용한 도시철도 운행비용 모형의 정립과 적용 (서울, 인천, 부산, 대구지하철을 중심으로))

  • Song, Sun-Ah;Suh, Sun-Duck
    • Journal of Korean Society of Transportation
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    • v.22 no.7 s.78
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    • pp.41-48
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    • 2004
  • We may consider the inducement of demand to public transportation as a solution to relieve traffic congestion and pollution. Subway has merits as moving on schedule, transporting more people than bus. But subway is required a vast investment in the early stage of construction has a huge debt. So it runs into red figures, and on this account, services of subway are falling more and more. Development of subway's operation cost function is useful to understand structure of subway's operation and catch the relations of operation cost and actual results. In addition, we can present the policy that is a helpful to the operation as development of operation cost function. But there are short of studies about operation cost deal with a subway comparison with local train. Because local train has many lines and data, on the other hand, subway has one to four lines and less data. Most of previous studies sought the operation cost function of Seoul. So this study aimed to develop and apply the operation cost function of Seoul, Incheon, Busan and Daegu area using full allocation method. In this study, we considered the number of passengers, track-km, train-km, revenue as actual results. By appling the operation cost function, we compared the average cost of each city and confirmed the existence of economies of scale about the number of passengers, train-km.

Issues of Natech Risk Management (Natech위험의 개념 및 주요 쟁점)

  • Oh, Yoon-Kyung
    • Journal of Environmental Policy
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    • v.13 no.4
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    • pp.79-105
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    • 2014
  • Natech risk is a type of complex disasters that natural hazards trigger technological disaster or industrial accidents. Research on Natech risk has been started from the mid-1990s in European countries and the Unites States, and drawn much more attention after the Fukushima nuclear accident caused by the 2011 East Japan earthquake. While early studies on Natech risk have focused on the causal natural hazards and possibility to occur, and the resulting spill of hazardous materials from the perspective of science and engineering, the recent research interests lie on effective Natech risk management. Especially, emphasizing the difference of Natech risk management from traditional disaster management, issues of uncertainty management, integration between natural disaster and technological disaster, and responsibility, has been drawn attention. In Korea, Natech risk has not been introduced as a research topic. Although some regulatory improvements have been made in nuclear safety and chemical Substance management after the Fukushima disaster, the potential impact of natural hazards in these areas has not been considered yet. It is necessary to raise the issues of Natech risk management in research and policy areas through active discussion and interdisciplinary approaches.

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Predictive Contamination of Animal Products Due th the Inhalation of Air and the Ingestion of Soil of Cattle in an Accidental Release of Radioactive Materials - Focusing on Contaminative Influence for Milk (원자력 사고시 가축의 공기 흡입과 토양 섭취에 의한 축산물의 오염 - 우유에 대한 오염 영향을 중심으로)

  • Hwang, Won-Tae;Kim, Eun-Han;Suh, Kyung-Suk;Jeong, Hyo-Joon;Han, Moon-Hee;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.28 no.4
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    • pp.299-309
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    • 2003
  • In an accidental release of radioactive materials to the environment the contaminative influence of animal products due to the inhalation of air and the ingestion of soil of livestock, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was investigated with the improvement of the Korean dynamic food chain model DYNACON Although mathematical models for both contaminative pathways have been established for considering all animal products and incorporated into the model, investigation was limited to milk. As a result, it was found that both pathways are influential in the contamination of milk in the case of an accidental release during the non-grazing period of dairy cows. In the case of an accidental release during the non-grazing period, the inhalation of air was more influential than the ingestion of soil in the early days following an accidental release. While, it was the opposite with the lapse of time. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was greater compared with the cases of no precipitation, in general, because of a stealer deposition of radionuclides onto the ground. Precipitation during an accidental release was a less influential factor in $^{131}I$ (elemental iodine) contamination compared with the $^{137}Cs\;and\;^{90}Sr$ contaminations. In the case of an accidental release during the grazing period of dairy cows, the contaminative influence due to the inhalation of air was negligible.

An Analysis on Beginning Secondary Science Teachers' Problems in their Teaching Practice through Collaborative Mentoring (협력적 멘토링 과정에서 나타나는 초임중등과학교사의 교수실행 문제점)

  • Park, Jihun;Nam, Jeonghee;Kwon, Jeongin
    • Journal of The Korean Association For Science Education
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    • v.35 no.4
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    • pp.557-564
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    • 2015
  • The purpose of this study is to examine the problems in the teaching practice of beginning science teachers who participated in the collaborative mentoring program to improve their teaching expertise. The participants were six beginning science teachers and six mentors at middle and high school levels. From each beginning science teacher and mentor teacher, journals, one-to-one mentoring records and transcripts, interviews and questionnaires, and transcripts conducted at the beginning, middle and the end of the mentoring program were collected. Seven aspects of the beginning science teachers' problems in their teaching practice were identified. The result showed that mentee teachers didn't set up specific learning objectives and they organized and presented lesson contents without considering students' proficiency level. Also, they found it hard to prepare for the lessons irrelevant to their major field of study and they tended to use convergent questions more than divergent questions. Mentee teachers tend to give teacher-centered rather than student-centered teaching. Beginning teachers' recognition of their problems in their teaching practice tends to lead changes in their teaching practice. Some of the problems that mentee teachers showed could be overcome if they recognized the problem through the collaborative mentoring program, but if not, it tends to remain throughout mentoring program.This study also highlighted the importance of reflection on beginning science teachers' practice.

Influence Factors of Online-Based Interpersonal Relationships by Developmental Level -Centered on Social Networking Service Users - (대인관계 발달 단계에 따른 온라인기반 대인관계에 미치는 영향요인 - 소셜네트워크 서비스(SNS) 사용자를 중심으로 -)

  • Heo, Song-Ji;Kim, Ja-Young;Jang, Hee-Jin;Ko, Hye-Young;Park, Su-E
    • Journal of Korea Game Society
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    • v.12 no.2
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    • pp.75-89
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    • 2012
  • In this paper, the correlation which is at work between affecting factors and interpersonal relationships' dimension depend on developmental level has been studied to search for clues about how to develop the online based interpersonal relationships -the fundamental aims of SNS related services- efficiently. People who'd ever entered into a relation through the 'online-based generated relationship' by SNS were divided into two groups on the development level. They were conducted a survey, and the results were derived using PLS statistics. As the result, 7 kinds of factors as social attraction, physical attraction, reciprocity, content quality, coexistence perception, information provision and similarity had an impact on the initial level of relationships, and 6 kinds of factors as social attraction, physical attraction, reciprocity, content quality, web appearance and coexistence perception had an impact on the developed level of relationships. This study could be utilized for the service design for facilitating interpersonal relationships efficiently by their level of development.

A Study of Co-Working Space Operation Strategy: Focused on Operation Elements Analysis by AHP Method (코워킹스페이스 운영전략 연구: AHP 기법을 통한 운영요소 분석을 중심으로)

  • Seo, Jong-Seok;Lee, Geun-Choon;Ock, Young-Seok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.4
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    • pp.157-165
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    • 2015
  • The purpose of this study is to suggest a successful operating strategy of co-working space. Therefore, the operating elements were identified through a literature research. And then, verified through site investigation and interview of operation managers. We found out that the high level operating elements are 'Co-working management', 'Membership management' and 'Supporting management' And the low level elements of Co-working management are 'Relationship facilitation', 'Networking event & Party' and 'Community & Communication', Membership management's are 'Service diversity & Price plan', 'Promotion & PR' and 'Alliance & Partnership', Supporting management's are 'Space & Interior', 'Facility & Device, Solution' and 'Mentoring & Education'. And the questionnaire was designed and conducted to Co-working space operators through the AHP method. As a result of the collected data analyzing, the highest priority was the operational element 'Community & Communication', and 'space and interior' is next, 'Service diversity & Price plan' is the third. The results were discussed with the relevant experts and it presents the following operating strategies. First, to create an environment suitable to voluntary coworking is the most important element. In particular, good management of 'Community & Communication' should be considered as a high priority operations strategy in a coworking space. Second, interior and space utilization helps in making the environment and atmosphere conducive to coworking. Office devices and facilities such as IT infra, printer, fax, scan, paper...etc are also important elements. But the reason why these necessary items are given a low priority is that these items don't need any special strategy. Third, in order to create a stable profit, 'Service diversity & Price plan' should be the characteristics of each coworking space because it will attract and secure enough customers. This study is valuable, it could be a great guideline for coworking space in an early stage to adopt operating model and strategy

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