• 생태와환경
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• 제50권4호
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• pp.374-380
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• 2017

Pine wilt disease (PWD) is one of the hazardous pine tree diseases in whole world. In Korea, PWD has been spreading since it was first observed in Busan in 1988. Dispersion of PWD is mainly mediated by its vectors such as Japanese pine sawyer. In this study, we characterized environmental condition including meteorological factors, geographical factors, and land use factors influencing on the occurrence of PWD. The occurrence data of PWD were collected at 153 sites where were the initial occurrence sites of PWD in local government regions such as city, Gun, or Gu scale. We used Akaike Information Criterion (AIC) to evaluate the relative importance of environmental variables on the discrimination of occurrence or absence of PWD. The results showed that altitude, slope, and distance to road were the most influential factors on the occurrence of PWD, followed by distance to building. Finally, our study presented that human activities highly influenced on the long term dispersal of PWD.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1652-1657
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• 2021

Nuclear materials can be utilized not only for peaceful uses, but also for military purposes; hence, the international community has devoted itself to the control, management and safeguarding of nuclear materials. Nuclear materials are of varying degrees of usability for development of nuclear weapons. Thus, several methods for assessing the attractiveness of nuclear materials for nuclear weapons purposes have been proposed. When these methods are applied to unirradiated depleted, natural, and low-enriched uranium (DU, NU, and LEU), they are certainly classified as non-attractive nuclear materials. However, when nuclear material attractiveness is to be evaluated for potential radiological dispersal device (RDD) uses, it is required to develop a different method for the different aspects and factors. In the present study, we derived a novel method for evaluating nuclear material attractiveness for use in RDD development. To this end, the specific activity and dose coefficient were identified as the two sub-factors, and, in consideration of those, the mass causing detrimental health effects was determined to be the main factor impacting on nuclear materials attractiveness. Based on this factor, the attractiveness of unirradiated DU, NU, and LEU for RDD use was qualitatively compared with that of ¹³⁷Cs.

• 한국작물학회지
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• 제55권4호
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• pp.365-370
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• 2010

본 연구는 유전자 조작 옥수수의 유전자 유출을 막기 위한 관리방법 개발의 목적으로 고려대학교 GMO 격리포장에서 2010년에 수행된 화분 비산실험의 결과를 이용하여 Yamamura(2004)의 Gamma model로 모델링하였다. 1. 모델의 결정계수는 0.44로 예측치가 실측치를 잘 설명하였다. 2 옥수수 화분의 최대 비산 방향은 북서쪽으로 나타났다. 3. 최대 비산 방향으로 타가수분율이 0.001까지 낮아지는 거리인 '유전자유출 한계거리(0.001)'는 525 m 그리고 국내법상 비의도적 GMO 혼입허용치인 0.03 까지 낮아지는 거리인 '최소 동일작물 재배 한계거리(0.03)'는 35 m로 나타났다.

• 한국건축시공학회지
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• 제16권1호
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• pp.77-85
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• 2016

본 연구에서는 소산 및 전투시설의 복토를 통한 방호성능 보강 정도에 대한 수치적인 판단근거를 제시하였다. 먼저 지근탄보다 직격탄의 피해가 더 크며 이를 방호기준에 적용해야 함을 폭발실증시험을 통해 확인하였다. 지근탄과 달리 직격탄의 경우 신관의 작동특성을 고려할 때 복토에 의한 방호가 중요하다. 복토를 위한 수치모형 제시를 위해 현장실사를 통해 방호시설 제원을 확보하고 이를 복토 물성치의 불확실성과 함께 고려하여 유한요소해석을 통한 방호성능 충족여부를 판단하였다. 해석결과를 토대로 로지스틱 회귀분석을 수행하여 복토를 통한 방호성능 보강을 위한 수치적 판단근거를 제시하였다. 본 연구에서 제시한 수치모형은 접적지역 내 소산시설 및 전투시설의 방호성능 보강정도 판단에 활용될 수 있다. 향후 폭발효과가 구조체에 미치는 요소에 대한 추가적 식별하거나 비선형 회귀모형을 이용한다면 보다 신뢰성있는 모델 제시가 가능할 것이다.

• 한국제4기학회지
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• 제21권2호
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• pp.49-53
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• 2007

• 대한치과의사협회지
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• 제26권1호통권224호
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• pp.65-71
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• 1988

• 환경생물
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• 제33권2호
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• pp.209-214
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• 2015

The Mesostigmata is an order of Subclass Acari either parasiting to diverse invertebrates or free-living predatory in terrestrial ecosystem. Phoresy is one of the unique behaviors of wingless arthropod dispersal by attaching winged arthropods. We collected mites attached on the dorsal part of abdomen adult sciarid fly, from mushroom culture. The mites were identified as Arctoseius cetratus Sellnick, 1940 in the family of Ascidae. Arctoseius cetratus has short J2, Z1, Z2, and S1, S2 setae, not reaching the bases of following setae. Posterior half of dorsal shield with longitudinal garland of puncta between J and Z setae, peritremes extending anteriorly to midlevel of coxaII. The genus Arctoseius and species Arctoseius cetratus are the first record in Korea. We provided the detail description of the species including the identification key in the family with some ecological notes.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.121.1-121
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• 2003

Dispersal of Xanthomonas axonopodis pv. citri, causing citrus bacterial canker disease on Unshiu orange was investigated at previously infested plots at Seogwipo in Jeju island of Korea. The bacterial pathogen overwintered in lesions started to multiply at tate May, and disease firstly observed one month after detection of phage from lesions. The disease gradually increased, however, it dispersed non-directionally to nearby plants from inoculum sources. Diseased plants were aggregated to form a cluster throughout the experiment. Population dynamics of phage on symtomless leaf surface and the disease severity were compared in the nursery, Increase of phage population on symptomless leaf surface preceded one month to that of the disease severity Population of phage increased constantly from late July to October, however, the disease severity decreased from late August to late October. It was assumed that the decrease of disease severity might be due to disease-induced defoliation.

• 안보군사학연구
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• 통권7호
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• pp.129-154
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• 2009

The principles of military operations(principles of war) are the fundamental principles ruling warfighting that made based on the experiences of wars from the time of ancient Greeks to the World War II. Recent wars such as Iraq War showed us the change of environment of war and the style of waging a war. It is believed that future war will be executed with the style of Rapid Deceive Operations, Effect Based Operations, Network Centric Operations. Therefor the principles of war which we use should be reconsidered whether it is useful or not in future warfare. By considering the present principles of operation which are using in many countries and analysing the style of waging future war, we suggest new principles of operations : principle of gravity, principle of mass and dispersal, principle of disturbance, principle of speed, principle of paralysis, principle of synchronization and integration, principle of leadership, and principle of information.

• 환경생물
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• 제21권2호
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• pp.181-188
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• 2003

In this study, soil seed and bud bank analysis were performed to abbess the mass of potential vegetation in soils less than 1 year old after covered and estimate the amount of seed bank transport through construction in urban area. The ratio of exotic species number to total species number in study sites and the landfill control site was 0.29 and 0.39, respectively. All plots pooled, mean species number and total mean seedling density per $\m^2$ in the top 10 cm of soil was 11$\pm$0 (average$\pm$S.E.) and 8037$\pm$221.Total plant seeds by artificial soil trasnsfer were estimated to be 53 thousand million $m^{-2}yr^{-1}$ in 10 cm soil depth. It reveals that soil transfer accelerates seeds and vegetation movement and makes urban vegetation mixed and common.