• Title/Summary/Keyword: 생태적 진화

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Environmental Studies on Masan Bay 1. Physical Factors and Chemical Contents (마산만의 환경학적 연구 1. 물리적 특성과 화학 성분함량에 대하여)

  • Kim, Jong Man;Han, Sang Joon;Lee, Jong Wha
    • 한국해양학회지
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    • v.11 no.1
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    • pp.25-33
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    • 1976
  • The physical factors and chemical contents were studied at 8 stations within Masan Bay, differing in depth and location with respect to inner and outer harbours. It is a relatively small bay with a long and narrow outlet. The water temperature and salinity at the inner bay was rather subject to change on weather condition of the neighbouring land than on the effects of the water mass of outer bay. The high nutrient contents in the bay were caused by the sewage and industrial activities. The outer harbour was less polluted than that of the inner bay; the high contents were significantly decreased from the entrance of the outer harbour. While the high disolved oxygen contents, over saturation in the surface strata may be the result of nearly all year round phytoplankton blooms, the lack of oxygen contents in the bottom strata were caused by the inadequate mixing of water mass and organic matters. The frequent red tide in the area may be the results of inflowing raw sewage, industrial activities of neighbouring land and inadequate mixing of water masses.

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Molecular Phylogenetic Study of the Barbel Steed (Hemibarbus labeo) in Seomjin River of Korea (한국 섬진강산 누치(Hemibarbus labeo)의 분자 계통유전학적 연구)

  • Park, Kiyun;Lee, Wan-Ok;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.52 no.3
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    • pp.221-230
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    • 2019
  • Barbel steed (Hemibarbus labeo) is a small freshwater fish species as semi-bottom dwellers distributed in eastern Asia. We carried out characterization of the cytochrome c oxidase subunit I (COI) gene from the mitochondrial DNA of H. labeo in the Sumjin River to identify the phylogenetic location of H. labeo in the genus Hemibarbus and Cyprinidae. Multiple alignment of the 577 bp COI sequence revealed high sequence homology (99~100%) between Seomjin River H. labeo. The nucleotide sequence similarity between H. labeo (HD1) and H. mylodon was 88.91% and that of H. longirostis was 88.81% among the three species found in Korea. In addition, the nucleotide sequence similarities of H. maculatus, H. meditus, H. umbrifer and H. barbus showed 98.97%, 97.20%, 96.87% and 98.85%, respectively. Phylogenetic analysis on seven species of the genus Hemibarbus showed that the H. labeo collected in this study formed two clades. One of which consisted of Hadong, Imsil, Kangjin. The other one formed a step with HD2, HD8 and HD9 of Hadong and the H. labeo reported in Busan, Asan and Seoul, Korea. Phylogenetic position of the H. labeo among Cyprinidae showed 0.143 for the evolutionary distance from Zacco platypus and 0.006 for the H. maculatus. In addition, the genetic position of the H. labeo among 28 species of Cyprinidae was found to be located in Group I, including Gobioninae fishes. The results of this study will provide key genetic information for the taxonomic comparison in Cyprinidae and study of model fish for pollution monitoring in freshwater environments.

Implementation of Pattern-Driven Web Test Automation Framework (패턴 중심의 웹 테스트 자동화 프레임워크의 구현)

  • Na, Jong-Chae;Jeong, Hyie-Soo;Ryoo, Seok-Moon
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.12
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    • pp.1239-1243
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    • 2010
  • The web environment is evolving rapidly. Testing in the web based software is an essential process to improve stability and productivity. Testing of complex web contents and ill(user interface) is most important thing. Implemented test cases are efficient when they are automated and reusable. But, most of the testing automation tools are focused on technical accessibility and functions still. A collaboration of the persons concerned and reusability of implemented test case are ignored. In this paper we propose an efficient way to design automated test case in web environment, and to share and pattern automated test cases we introduce testing framework called NTAF(NHN Test Automation Framework.). The NTAF is based on open source framework. It provides integrated testing environment that web testing cane be automated and managed continuously.

Mammalian Research Topics and Trends in Korea (국내 포유류 연구의 주제와 동향)

  • Ko, Byung June;Eo, Soo Hyung
    • Korean Journal of Environment and Ecology
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    • v.31 no.1
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    • pp.30-41
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    • 2017
  • Mammals in Korea have been studied in various fields such as animal science, veterinary medicine, laboratory animal science, ecology, and genetics. As the importance of biodiversity has been emphasized recently, conservation and management of mammals have attracted much public attention. However, in spite of such an increase in scientific research and public interest, it is still difficult to find a report or summary to grasp the trend of mammalian research in Korea. The purpose of this study is to provide the basic data for future plans of the detailed research area and the related policies by grasping the research trends of mammals in Korea. Using text-ming and co-word analysis, we analyzed 392 mammalian research papers published in Korean national journals as of 2015. Our results showed that the number of mammalian research papers published in Korea has gradually increased and that the research target species have also become increasingly diverse. The major research areas identified through text-mining and co-word analysis are (1) evolution/phylogenetics/genetics, (2) environmental science/ecology, (3) embryology/reproductive biology/cell biology, (4) veterinary medicine related to parasites, (5) parasitology related to rodents, (6) bacteriology/virology, (7) anatomy/cell biology/laboratory animal science, (8) veterinary science related to morphology and anatomy, (9) animal science, (10) marine mammalogy, and (11) Chiroptera (bat) research. Environmental science/ecology has been the most active field among the 11 research areas in recent times, and the proportion of research has increased sharply compared to the past. Environmental science/ecology is the core of biodiversity conservation, and as the importance of biodiversity has been emphasized in recent years, researchers' interest in mammal ecology appears to have increased. We expect that the results of this study will be useful for future research plan and related policies on mammals in Korea.

기업 성장단계 별 외부 협력 및 정부 인증 지원제도가 성과에 미치는 영향

  • Park, Da-In;Park, Chan-Hui
    • 한국벤처창업학회:학술대회논문집
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    • 2018.11a
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    • pp.187-192
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    • 2018
  • 현재 급변하는 정보기술, 다양성을 추구하는 시장의 니즈, 미리 예측하지 못한 다양한 형태의 경쟁자 등의 출현으로 인해 경영환경이 급변하고 있는 것은 더 이상 새로운 현상이라고 보기는 어렵다. 이와 같이 급변하는 경영 환경은 기업 간 경쟁 심화를 불러일으키고 있으며, 경쟁 심화는 생존 및 발전을 위해 기업 특성에 맞지 않는 무분별한 전략을 활용하면서 오히려 역효과를 내고 있다는 문제를 야기하고 있다. 특히 변화하고 있는 환경 내 벤처기업 및 창업기업들의 경우 창업 후 생존율이 점차 낮아지면서 일반 기업들에 비해 경쟁력을 갖춘 기업을 찾아보기 어려운 것이 현실이다. 이에 벤처기업들은 도태되지 않고 생존하기 위해경쟁력을 강화시킬 수 있는 다양한 전략을 구사하고 있다. 벤처기업은 하나의 비즈니스 생태계 내 유기적 생명체로서 진화하기 위해 제품이나 산업의 수명주기와 마찬가지로 창업기, 초기 성장기, 고도 성장기, 성숙기, 쇠퇴기 등의 정형화된 단계를 거친다. 따라서 벤처기업은 무차별적인 전략을 통해 기업의 생존 및 성장을 도모 하는 것이 아니라 해당 기업이 놓인 수명주기 단계별로 전략, 조직 구조, 의사결정방식, 통제유형 등을 상이하게 판단하고 이에 적절한 전략을 수행해야 한다. 예를 들어, 동일 생산요소를 투입하더라도 이를 적용할 수 있는 지식이 있는 경우 더 높은 가치 창출이 가능(Aghion & Howitt, 1992) 하지만 창업 초창기의 기업은 고도 성장기의 기업보다 보유한 지식 수준 및 경험이 상대적으로 낮기 때문에 다양한 협력을 필요로 한다. 그러나 현재의 여러 선행연구들은 기업이 처한 상황을 고려하지 않은 단편적인 대처 방안이거나 혹은 부분적인 방법론을 제공하는 수준에 그치고 있다는 한계가 있다(이병헌 외, 2014). 따라서 본 연구에서는 '2016년 벤처기업정밀실태조사' 데이터를 기반으로 기업의 외부 협력 정도 및 벤처기업 지원제도 활용 정도가 경쟁력과 성과에 미치는 영향이 기업의 수명주기별로 상이하다고 보고 관련 전략 프레임워크를 제시하고자 한다.

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The naturalized Plants and regulating measures in Dokdo (독도 귀화식물과 관리방안)

  • Lim, Dong-Ok;Hwang, In-Chun;Hwang, Jung-Hwan;Park, Seon-Joo
    • Korean Journal of Plant Resources
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    • v.22 no.1
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    • pp.96-101
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    • 2009
  • Dokdo was formed since when four million six hundred thousand to two million five hundred thousand. Dokdo, Ulreung Island and the mainland in Korea are not touch each other since the formation, therefore, Dokdo are very important island for discussion of plant evolution from plant geography point of view. Plants of Dokdo was enlisted as 60 taxa, 27 families, 52 genera, 50 species and 10 varieties. The naturalized plants of a wide sense is composed of 25 taxa, two tree species as Lonicera morrowii and Elaeagnus macrophylla, and 23 herbs. The naturalized plants were identified of 5 species as Sonchus oleraceus, Brassica juncea var. integrifolia, Rumex crispus, Chenopodium album, and Bromus unioloides. Total naturalized plants are 32 taxa, ratio of total naturalized plants per a existing species was 60 percentage. Accordingly Vegetational environment of Dokdo was interpreted very incomplete state as well as severe ecological disturb by invade species. Preparation of a regulating plan on naturalized plants and concern of a policy decision are requested in the conservational dimension for native species in Dongdo. For the conservation of native species in Dokdo, there are prepared that a regulating plan as block of the influx and eradication etc. and a policy decision of naturalized plants are prepared for view of the conservation for native species in Dokdo.

A Design of Power System Stabilization of TCSC System for Power system Oscillation Damping (전력 시스템의 동요 억제를 위한 TCSC용 안정화 장치 설계)

  • 정형환;허동렬;왕용필;박희철;이동철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.2
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    • pp.104-112
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    • 2002
  • In this paper, it is suggested that the selection method of parameter of Power System Stabilizer(PSS) with robustness in low frequency oscillation for Thyristor Controlled Series Capacitor(TCSC) using Geletic Algorithm(GA). A TCSC meddle consists of a stories capacitor and a parallel path with a thyristor valve and a series inductor. Also in in parallel, as is typical with series capacitor applications, is a metal-oxide varistor(MOV) for overvoltage protection. The proposed PSS parameters are optimized using GA in order to maintain optimal operation of TCSC which is expected to be applied in transmission system to achieve a number of benefits under the various operating conditions. In order to verify the robustness of the proposed method, we considered the dynamic response of angular velocity deviation and terminal voltage deviation under a power fluctuation and rotor angle variation.

Analysis and Implications of Singapore's Smart Nation: Focusing on the Implemental Means of Smart City Initiative (싱가포르 스마트 네이션의 분석과 함의: 스마트시티 이니셔티브의 실행적 수단을 중심으로)

  • Kim, MyungHee
    • Journal of Convergence for Information Technology
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    • v.11 no.1
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    • pp.1-11
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    • 2021
  • This study focuses on that, unlike evolving smart technology, goals, policies, and administrative organization elements are tools that do not change in smart city implementation, and by applying the concept of policy implemental means, the characteristics of the Singapore Smart Nation Initiative are analyzed, results are derived and implications are suggested. To this end, literature analysis is conducted based on the case analysis framework with "Smart Nation" as an analysis unit and "project, administration, citizen engagement" as analysis elements. The implications through analysis are as follows. First, it is required to establish a state-led initiative for a major transformation into a digital society. Second, it is necessary to establish executive agencies directly under the president or prime minister for effective implementation of the initiative. Third, complementary programs at the level of detailed strategies, administrative organizations, and citizen participation as a means of implementation, should be considered and the flow of the recent digital ecosystem should be reflected. Fourth, it is necessary to promote a national movement for a great transformation into a digital society where all the people participate.

Evolution of OTT Service and Changes of Pay TV Industry (OTT 서비스 진화와 유료방송 생태계 변화)

  • Do, Joonho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.2
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    • pp.143-149
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    • 2022
  • The diffusion of OTT service has brought the fundamental changes in the value chain of the existing media industry. OTT service based on the public Internet has increased the number of subscribers by using dominant marketing capability, making the pay TV platform player's ability to connecting users powerless. This study examined the changes in the media market and pay TV industry in the USA due to the diffusion of OTT service and analyzed the changing strategies of media firms. The number subscribers of the expensive pay TV service in the USA has diminished, experiencing cord cutting and cord shaving due the diffusion of OTT. OTT players are changing the media market, showing the dramatic excellence in making original contents and distributing the newly released movies. Examination of the recent merger and acquisition cases of media firms tells that the investment in making original contents has increased in order to have the competitiveness in OTT business. The future media industry will be rapidly reshaped mainly based OTT service and strategic judgement is important to maintain the competitiveness of all media firms in the existing value chain of media industry.

The Influence of Professional YouTuber's Reputation on Viewer Loyalty and Subscription Intention : Focused on Moderating Effect of YouTuber Authenticity (전문 유튜버의 평판이 충성도 및 구독의도에 미치는 영향 -유튜버 진정성의 조절효과를 중심으로-)

  • Eun Chang-Ik
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.221-237
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    • 2023
  • This study was conducted as part of a phased study aimed at closely examining the mutual ecosystem between creators and viewers through paying attention to the personal media environment that is in the center of rapid changes in the media industry and particularly exploring the areas of activity of the single-person or minority media creators who lead the mobile media environment that could be accessed, viewed and produced anywhere. In particular, this study aimed to not only pay attention to the situation in which the potential to expand professional YouTuber areas encounters the changing desire and demand of content service users who continue to become more evolved as time passes, but also examine the influence of the reputation of professional YouTubers on users' loyalty and subscription intention, examine the moderating effect of sincerity on the relationship between YouTubers and users, and demonstrate such relationship formation process based on concrete data. In the conclusion section, implications that can be drawn from the study results and suggestions for further studies in the future were proposed.