• 한국습지학회지
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• 제11권2호
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• pp.99-106
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• 2009

물거미(Argyroneta aquatica Clerck)는 전세계적으로 희귀한 거미로 물속에서 생활사를 보낸다. 우리나라에서는 경기도 연천군 은대리의 소규모 습지에서만 발견되고 이곳은 천연기념물로 지정되어 보호되고 있다. 본 연구에서는 물거미 서식 습지에서 개체군 밀도를 측정하고, 식생을 비롯한 생태학적 특성을 밝히고, 보전 방안과 관광자원화 방안을 제안하고자 시도되었다. 그 결과 물거미 밀도는 1마리/$m^2$, 총 개체수는 약 8,000마리/ha이었다. 물거미가 사는 곳의 습지는 수위변동이 심하였고, 현존식생은 나도겨풀과 갈대가 우점하였고, 물속에는 통발이 공통적으로 출현하였다. 본 지역은 현재 육화가 진행되고 있고, 서식지가 단절되어 있어 물거미를 보전하기 위해서는 건기에 물을 공급하고, 서식지를 상호 연결하는 생태통로가 필요하다. 또한 물거미 서식지를 활용한 생태관광화를 위한 방안에 대하여 제안하였다.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2354-2363
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• 2018

This paper proposed a novel double closed control strategy for single-phase voltage source pulse width modulation (PWM) rectifier based on active disturbance rejection control (ADRC) and dq current decoupling control. First, the mathematical model of the single-phase PWM rectifier in the d-q axis synchronous rotating reference frame is established by constructing a virtual component using a second-order generalized integrator (SOGI). Then, the mathematical model is simplified according to the active power conservation, and the first-order equation of single-phase PWM rectifier voltage outer loop is acquired. A linear auto-disturbance rejection controller is used to design the voltage outer loop according to the first-order equation. Finally, the proposed control strategy and the traditional PI control are compared and verified by simulation and physical experiments. Both simulation and experimental results confirm that the proposed control strategy has excellent dynamic performance and strong rejection ability to disturbances.

• 한국농촌건축학회논문집
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• 제8권1호
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• pp.101-110
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• 2006

During high speed economic growth period in Korea, our society has focused it's energy on the economic and social development based on the strategy of demolition and destruction of all our natural and man-made environment. In progress with that trend, our small cities in Korea also have just followed the metropolitan physical development pattern and considered that imitation of those metropolitan cities' or western cities' changes be the same meaning of "modernization". Therefore, our valuable urban and architectural heritages have been constantly destructed and that situation has been same in Anseong. Now in the new trend of environmentally sustainable urban design and at the new millenium period, we have to focus our attention on the retaining strategy of city's historicity as a city planner or an architect, and the first step for this strategy shall be to clarify the transition process of urban structure, especially of C.B.D. area of small cities since pre-industrial period.

• 한국산림과학회지
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• 제83권2호
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• pp.191-204
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• 1994

삼림의 급격한 황폐화의 원인은 지구 환경의 악화와 무분별한 목재 자원의 남벌에 있다. 이러한 대규모의 삼림자원의 파괴에 의해 사라져가는 삼림 면적의 크기도 중요하지만 그에 못지 않게 그 안에 들어있는 식물종이 감소되어 가고 멸종되어 가는 것이 더욱 큰 문제가 된다. 이러한 종의 감소나 멸종이 가시적인 것이라고 한다면 종내의 유전변이의 감소는 눈에 보이지는 않지만 진화과정에 있어서 종을 유지하는데 필수적인 유전자 변이 폭이 좁아지기 때문에 매우 심각한 문제가 된다. 재배작물에 있어서 유전자 보존은 육종을 위한 측면에서 중요한 연구분야로 인식되어 왔다. 그러나 야생종인 삼림의 경우에는 현재 인간이 육종에 필요한 최소한의 개체만 유지 보존함으로써 유전변이가 심하게 축소되어 지속적으로 생존 진화할 수 있는 기본적 유전자 변이를 잃어버리게 될 위험에 처할 수 있기 때문에 삼림의 유전자보존이 절대적으로 필요한 것이다. 현재의 삼림 유전자 보존 정책은 현지보존, 현지외 보존, 시설내 보존으로 나누어 수행하고 있는데 아직도 그 방법이 확정되어 있지 않아서 많은 시행착오를 거듭하고 있다. 특히 광범위하게 분포되어 있는 같은 종의 삼림내 임목들간의 유전자변이를 조사 분석할 적당한 방법이 없으며 (동위효소변이에 많은 것을 의존하고 있으나 동위효소변이만으로 충분하지 못하다), 현지보존의 경우에도 얼마나 큰 집단을 또 어떤 행태로 보존해야 하는가에 대한 집단유전학적 이론 정립이 완전하지 못하다. 또한 현지외 보존의 경우 현지보존림의 유전변이를 빠짐없이 포함되도록 조성해야 할 구체적인 방법을 알지 못하고 있는 실정에 있다. 시설내 보존의 경우 종자 보관이나 화분 보관과 같은 기술적인 것은 재배작물의 방법을 적용하면 되지만 어떤 집단의 종자나 화분을 채집 보관해야 하는지에 대한 집단유전학적 근거가 아직 확실히 마련되고 있지 않다. 시설내 보존인 경우 기왕에 육종에 의해 선발된 개체를 유전자형(개체) 상태로 보존함으로써 부가가치를 높일 수 있을 것이며, 이러한 연구는 새롭게 개발되고 있는 조직배양 및 유전공학적 기법을 이용하므로써 발전할 수 있는 여지가 많은 연구 분야이다. 현지보존의 경우 유전자 보존만의 목적으로 조성된 삼림뿐만 아니라 다른 목적으로 보호 받고 있는 많은 삼림, 예를 들면 국립, 도립공원, 보안림, 노거수 등에 대한 적절한 생태유전학적인 연구를 통하여 유전자원으로 이용할 수 있는 방법이 강구되어야 하며, 현지외 보존의 경우에도 유전자원 보존림의 조성 뿐만 아니라 임목육종과정에서 기 조성되어 있는 채종원, 산지시험림, 차대검정림, 클론보존원 등에 대해서도 적절한 유전학적 연구 조사를 수행함으로써 현지외 유전자 보존림으로 이용할 수 있게 될 것이다.

• Animal cells and systems
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• 제16권1호
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• pp.41-49
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• 2012

Eighteen new polymorphic microsatellite markers were developed for the Korean mi-iuy croaker ($Miichthys$ $miiuy$, Perciformes, Sciaenidae), and allelic variability was compared between a wild population in Mokpo, Korea, and a hatchery population in Tongyeong, Korea. All loci were amplified readily and demonstrated allelic variability, with the number of alleles ranging from 5 to 37 in the wild population, and from 4 to 12 in the farmed population. The average observed and expected heterozygosities were estimated, respectively, to be 0.74 and 0.78 in the hatchery population samples, and 0.79 and 0.86 in the wild samples. These results indicate lower genetic variability in the hatchery population compared with the wild population, and significant genetic differentiation between the wild population and the hatchery samples ($F_{ST}$=0.058, P<0.001). These microsatellite loci may be valuable for future population genetic studies, monitoring changes in the genetic variation within stocks in a commercial breeding program, conservation genetics, and molecular assisted selective breeding of the mi-iuy croaker in the future.

• Journal of Ecology and Environment
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• 제42권3호
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• pp.111-119
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• 2018

Background: Juniperus chinensis L. populations are distributed locally on several areas including coastal cliffs which are difficult to access in the central eastern Korea. Wild populations inhabit relatively barren environments such as rocky areas and cliffs, which are very sensitive to even minor environmental disturbances including artificial interventions and natural disturbances, and thus demonstrate great fluctuations in the population size and density. This study aims to analyze the genetic diversity, differentiation, and genetic structure of each population in order to provide useful data required to establish a substantial conservation strategy of J. chinensis. Results: The genetic diversity of J. chinensis at the population level (P = 78.7%, h = 0.282, S.I. = 0.420) was somewhat higher compared with those measured in the same genus, Juniperus. The genetic differentiation degree among nine populations established naturally in central eastern Korea was 11.50% and that among sub-populations within the same area was 5.52%. On the other hand, genetic variation of individuals within the populations was 82.93%. But frequency of the main allele was different among loci. In particular, fixation of allele frequency and occurrence of rare allele in the highly isolated population suggest a likelihood that genetic drift would occur in populations of this plant. As the result of analysis on the genetic structure of nine populations, nearby populations and isolated populations tended to form separate clusters from each other as the hypothetical number of clusters (K) increase. Conclusions: This result implies that if the population size of J. chinensis is reduced due to environmental change and artificial and/or natural disturbances in the future, it could affect negatively on the genetic diversity of the plant species. In order to maintain and conserve genetic diversity of J. chinensis, ecological network, which can help genetic exchange among the local populations, should be prepared, and conservation strategies in situ as well as ex situ are also required with continuous monitoring.

• 환경영향평가
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• 제17권2호
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• pp.133-141
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• 2008

The loss, alteration, and fragmentation of habitat have led to a reduction of biodiversity. The growing awareness of the negative effects of habitat fragmentation on natural systems has resulted in conservation strategy that is concerned with not only population and habitat level but also ecosystem and landscape level. Especially, ecological network to link core areas or major habitat patches is one of the most important issues. Recently, landscape connectivity is increasingly used in decision making for fragmented landscape management in order to conserve the biodiversity in the regional scale. The objective of this study was to find potential forest as a ecological corridor in Go-yang city, Gyung-gi province using cost-distance modelling method that can measure connectivity based on animal movement. 'Least cost-distance' modelling based on functional connectivity can be useful to establish ecological network and biodiversity conservation plan. This method calculates the distance modified with the cost to move between habitat patches based on detailed geographical information on the landscape as well as behavioural aspects of the animal movement. The least cost-distance models are based on two biologically assumptions: (1) dispersers have complete knowledge of their surroundings, and (2) they do select the least cost route from this information. As a result of this study, we can find wildlife moving route for biodiversity conservation. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale, because this is reflection of geographical information and behavioural aspects of the animal movement.

• Journal of Microbiology
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• 제45권5호
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• pp.422-430
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• 2007

Clonostachys rosea (syn. Gliocladium roseum) is a well-known biocontrol agent and widely distributed around the world. In this study, an endochitinase gene Crchi1 was isolated from the mycoparasitic fungus C. rosea using the DNA walking strategy. The Crchi1 ORF is 1,746 bp long and interrupted by three introns. The cloned gene Crchi1 encodes 426 amino acid residues and shares a high degree of similarity with other chitinases from entomopathogenic and mycoparasitic fungi. Several putative binding sites for transcriptional regulation of Crchi1 in response to carbon (5'-SYGGRG-3') and nitrogen (5'-GATA-3') were identified in the upstream of Crchi1. Expression of Crchi1 gene in different carbon sources was analyzed using real-time PCR (RT-PCR). We found that the Crchi1 expression was suppressed by glucose but strongly stimulated by chitin or solubilized components of the cell wall from Rhizoctonia solani. Phylogenetic analysis of chitinases from entomopathogenic and mycoparasitic fungi suggests that these chitinases have probably evolved from a common ancestor.

• 농촌계획
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• 제12권4호
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• pp.115-123
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• 2006

The direct payment program for rural landscape conservation in practice since 2005. Recently it is the policy or plan of direct payment for rural landscape conservation attracts great interests as they may help rural people who are very disadvantaged. This paper presents the status of the direct payment program for landscape conservation in rural area and proposed improvements to the program as following; 1) to diversify the plant species, 2) to include other rural elements than plants, 3) to enlarge the areas of crop plantation, 4) to simplify and clarify application process. We sampled two pilot programs, one of spring flower crop and the other of autumn flower crop, and questionnaire surveyed visitors, local government officers and farmers in order to find problems and suggest improvements.

• Journal of Contemporary Eastern Asia
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• 제13권1호
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• pp.69-81
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• 2014

While much in the field of public management has emphasized the importance of nonprofit advocacy activities in policy and decision-making procedures, few have considered the relevance and impact of leading actors on structuring diverse patterns of information sharing and communication through social media. Building nonprofit advocacy is a complicated process for a single organization to undertake, but social media applications such as Facebook and Twitter have facilitated nonprofit organizations and stakeholders to effectively share information and communicate with each other for identifying their mission as it relates to environmental issues. By analyzing the Australian Marine Conservation Society's (AMCS) Twitter network data from the period 1 April to 20 April, 2013, this research discovered diverse patterns in nonprofit advocacy by leading actors in building advocacy. Based on the webometrics approach, analysis results show that nonprofit advocacy through social media is structured by dynamic information flows and intercommunications among participants and followers of the AMCS. Also, the findings indicate that the news media and international and domestic nonprofit organizations have a leading role in building nonprofit advocacy by clustering with their followers.