• The Plant Pathology Journal
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• 제32권6호
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• pp.508-518
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• 2016

Early blight of tomato caused by Alternaria solani, is responsible for severe yield losses in tomato. The conidia survive on soil surface and old dry lower leaves of the plant and spread when suitable climatic conditions are available. Macroclimatic study reveals that highest inoculum concentration of Alternaria spores appeared in May 2012 to 2013 and lowest concentration during January 2012 to 2013. High night temperature positively correlated and significantly (P < 0.01) involved in conidial spore dispersal and low relative humidity (RH) displayed significant (P < 0.05) but negative correlation with conidial dispersal. The objective of the study was to modify microclimatic conditions of tomato crop canopy which may hamper conidial dispersal and reduce disease severity. We evaluated effect of marigold intercropping and plastic mulching singly and in consortia on A. solani conidial density, tomato leaf damage and microclimatic parameters as compar to tomato alone (T). Tomato-marigold intercropping-plastic mulching treatment (T + M + P) showed 35-39% reduction in disease intensity as compared to tomato alone. When intercropped with tomato, marigold served as barrier to conidial movement and plastic mulching prevented evapotranspiration and reduced the canopy RH that resulted in less germination of A. solani spores. Marigold intercropping and plastic mulching served successfully as physical barrier against conidial dissemination to diminish significantly the tomato foliar damage produced by A. solani.

• 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.

• 암석학회지
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• 제22권4호
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• pp.273-289
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• 2013

강하화산재는 농업과 기반시설에 다양한 형태의 피해를 발생시킬 수 있는 악명 높은 재해이며, 특별히 항공과 인체 건강에 가장 유해하다. 본 연구는 백두산 화산으로부터 폭발적 분화에 의하여 화산재가 확산되고 퇴적되는 것을 모델링하기 위한 목적으로 개념적인 모델 설계를 논의하고자 한다. 이는 모델의 가정과 경계 조건에 대한 토의와 더불어 개념적인 모델의 상세 다이어그램, 가능한 입력 파라미터, 단위, 방정식에 대한 논의를 포함한다. 모델에 포함되어 있는 두 가지 주요 과정은 화산재의 확산과 퇴적이며, 만약 모델이 설계되면 모델을 실행시켜 얻을 수 있는 것은 분연주에 포함된 미세 화산재의 총량, 화산재의 이동 거리, 지표면에 침적되는 화산재 두께 등이다.

• 천문학회보
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• 제42권1호
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• pp.38.1-38.1
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• 2017

We report the results of three-dimensional radiation hydrodynamic simulations of star cluster formation in turbulent molecular clouds, with primary attention to how stellar radiation feedback controls the lifetime and net star formation efficiency (SFE) of their natal clouds. We examine the combined effects of photoionization and radiation pressure for a wide range of cloud masses (10^4 - 10^6 Msun) and radii (2 - 80 pc). In all simulations, stars form in densest regions of filaments until feedback becomes strong enough to clear the remaining gas out of the system. We find that the SFE is primarily a function of the initial cloud surface density, Sigma, (SFE increasing from ~7% to ~50% as Sigma increases from ~30 Msun/pc^2 to ~10^3 Msun/pc^2), with weak dependence on the initial cloud mass. Control runs with the same initial conditions but without either radiation pressure or photoionization show that photoionization is the dominant feedback mechanism for clouds typical in normal disk galaxies, while they are equally important for more dense, compact clouds. For low-Sigma clouds, more than 80% of the initial cloud mass is lost by photoevaporation flows off the surface of dense clumps. The cloud becomes unbound within ~0.5-2.5 initial free-fall times after the first star-formation event, implying that cloud dispersal is rapid once massive star formation takes place. We briefly discuss implications and limitations of our work in relation to observations.

• 한국의상디자인학회지
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• 제19권2호
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• pp.39-48
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• 2017

Transfer printing is a method to combine printing and dyeing technology by the use of sublimation. It is an environmentally-friendly printing method that saves costs, reduces the production processes by the omission of the washing process, and saves time by maintaining quality. Due to the development of transfer printing, a high value added printing technology is available now but color fastness to sublimation of the printing products is still low since there are few dyes that have an affinity to the fabrics and the application technology is still inadequate. Specially, in case of high concentration black dyes, eco-label type black dyes, which is a substitution for general dispersal dyes, have been developed while general dispersal black dyes are still used, creating issues such as color differences on the surface and back side of the fabrics and contamination by friction after transfer printing. There are also some restricted substances such as allergens. To address these issues, high concentration black dyes and application technology that are environmentally-friendly and that have over 16 K/S through the use of single dyes with excellent color fastness, fixation ability, and similar melting temperature were developed for this study.

• 한국해양학회지:바다
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• 제5권4호
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• pp.295-304
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• 2000

수리적인 환경 요인(조석, 바람 등)에 따른 하계 서남극 킹조지섬 마리안 소만의 수층 특성과 부유물질 분산을 이해하기 위해 내만에 유빙이 점유했던 시기에 30분 간격으로 CTDT연속 관측을 수행하였고 공간적인 표층 해수의 특성(수온과 염분)과 부유물질농도가 측정되었다. 소만 중앙의 수층은 탁도의 관점에서 크게 1)저온 ${\cdot}$ 저염 ${\cdot}$ 고탁도의 표층 플름과 2)고온 ${\cdot}$ 고염 ${\cdot}$ 저탁도의 맥스웰 만 유입수로 나누어진다. 소만 안쪽의 빙벽 앞과는 달리 빙하기저부 유출에 의한 담수성 수층이 나타나지 않았다. 고온의 맥스웰 만 표층수와 조수빙하/유빙의 열적 융빙은 표층 혼합층을 발달시키며 특히 소만 내 유빙의 점유와 거동으로 인해 맥스웰 만 유입수의 수층 특성이 불안정해진다. 이러한 수층의 불안정으로 인해 조석주기에 따른 맥스웰 만 유입수와 표층 플름의 거동은 나타나지 않았다. 소만 북부 연안에 나타나는 표층 플름에 비해 고온 ${\cdot}$ 고염 ${\cdot}$ 고탁도 표층 플름은 강한 북서풍 계열의 바람으로 위버 반도 서부 연안을 따라 중앙 분지로 유입되는 연안류이다. 표층 플름의 육성기원 쇄설물은 주로 급경사 연안의 빙벽 가장자리와 일부 해안가의 융설수류로부터 유입되며 조석과 바람에 의해 분산되고 조절된다. 특히 대조차 시기의 북서풍은 고탁도의 표층 플름을 내만에 체류시키며 소만 분지에 육성기원 쇄설성입자의 퇴적을 증가시킨다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.213-215
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• 1995

This paper is concerned with a coplanar pursuit-evasion game of one inertial evader and two identical noninertial pursuers. The terminal time is fired and the payoff is the distance between the evader and the nearest pursuer when tile game is terminated. The value functions and the strategies is constructed for all the game surface. To get a value function, we use the generalization of the Bellman-Isaacs fundamental equation.

• Environmental Engineering Research
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• 제17권3호
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• pp.167-174
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• 2012

In situ particle size spectra are obtained from two sequent cruises in order to evaluate the physical consequences of suspended particulate matters caused by episodic storm runoff from the Santa Ana River watershed, an urbanized coastal watershed. Suspended particles from various sources including surface runoff, near-bed resuspension, and phytoplankton are identified in empirical orthogonal function (EOF) analysis and an entropy-based parameterization (Shannon entropy). The first EOF mode is associated with high turbidity and fine particles as indicated by the elevated beam attenuation near the Santa Ana River and Newport Bay outlets, and the second EOF mode explains the suspended sediment dispersal and particle coarsening at the near-surface plume. Chlorophyll particles are also distinguished by negative magnitudes of the first EOF mode, which is supported by the relationship between fluorescence and beam attenuation. The integrated observation between the first EOF mode and the Shannon entropy index accentuates the characteristics of two different structures and/or sources of sediment particles; the near-surface plumes are originated from runoff water outflow, while the near-bottom particles are resuspended due to increased wave heights or mobilizing bottom turbidity currents. In a coastal pollution context, these methods may offer useful means of characterizing particle-associated pollutants for purposes of source tracking and environmental interpretation.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.302-305
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• 2007

During the CareBeijing campaign in September 2006, Imaging Differential Optical Absorption Spectroscopy (IDOAS) measurements were made over the city of Beijing, China using a spatial resolution of 146 pixels horizontally and 61 pixels vertically, each with a field of view of $0.133^{\circ}$ and $0.072^{\circ}$ in the horizontal and vertical directions, respectively. Using Fraunhofer reference spectra (FRS) for the evaluation of data for two consecutive days, the diurnal variation of $NO_2$ distributions was determined from data measured every single hour from 08:00 until 16:00 on September 9 and 10. Both days presented a fairly clear sky with high visibility. The setup allowed detailed images of the low surface $NO_2$ distribution over Beijing. Images with less than a 30-min temporal resolution showed variation of plume dispersal in both horizontal and vertical directions. An in-situ measurement was also conducted. Results from both instruments are interpreted by considering local emission sources and wind conditions.

• 방사성폐기물학회지
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• 제5권3호
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• pp.199-212
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• 2007

IP-2형 운반용기는 정상운반조건에서의 자유낙하시험 및 적층시험을 수행한 후에 운반내용물의 분산 및 유실이 없어야 하며 외부표면에서의 방사선량률이 20%이상 증가할 수 있는 차폐능력의 상실이 없어야 한다. 본 연구에서는 두꺼운 철판을 구조재로 사용하며 볼트체결방식의 뚜껑을 가진 IP-2형 운반용기에 대한 구조 안전성을 평가하기 위한 해석적인 방안을 제안하였다. 해석적인 방법을 통하여 원자력발전소에서 발생된 방사성폐기물 드럼을 폐기물 처리시설에서 임시저장고까지 운반하기 위한 두 종류의 IP-2형 방사성폐기물 운반용기에 대하여 자유낙하조건에서 운반내용물의 분산 및 유실과 차폐손실이 없음을 확인하였다. 자유낙하조건에서 운반내용물의 분산 및 유실을 평가하기 위하여 최대 볼트단면 평균응력값과 최대 뚜껑열림량을 볼트의 인장강도와 뚜껑부에 존재하는 단차와 비교 평가하였다. 또한 최대 차폐두께 감소량을 이용하여 차폐손실을 평가하였다. 자유낙하조건에 대한 동적충돌해석을 검증하고 구조 안전성을 시험적으로 평가하기 위하여 자유낙하시험을 다양한 방향으로 실시하였다. 자유낙하시험에서는 운반내용물의 분산 및 유실은 볼트체결방식의 뚜껑에서 볼트의 파손 및 플랜지의 변형 등을 검사하여 평가하였으며, 차폐손실은 초음파 두께 측정기를 이용한 차폐두께를 측정하여 평가하였다. 해석에 대한 검증을 위하여 시험에서 취득한 변형률과 가속도를 동일한 위치에서 얻어진 해석결과와 비교하였다. 해석결과는 시험결과에 비하여 보수적인 결과를 보여주므로 해석에서 입증한 IP-2형 방사성폐기물 운반용기의 안전성은 보수적인 결과이다. 마지막으로 유한요소해석을 통하여 적층조건에 대한 IP-2형 방사성폐기물 운반용기는 안전함을 입증하였다.