• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2006년도 추계학술대회 논문집
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• pp.102-108
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• 2006

The three-dimensional flows in the Weis-Fogh mechanism are studied by flow visualization and numerical simulation by the discrete vortex method. In this mechanism, two wings open, touching their trailing edges (fling), and rotate in opposite directions in the horizontal plane. The structure of the vortex systems shed from the wings is very complicated and their effects on the forces on the wings have not yet been clarified. The discrete vortex method, especially the vortex stick method, is employed to investigate the vortex structure in the wake of the two wings. The wings are represented by lattice vortices, and the shed vortices are expressed by discrete three-dimensional vortex sticks. The vortex distributions and the velocity field are calculated. The pressure is estimated by the Bernoulli equation, and the lift on the wing are also obtained.

• 한국염색가공학회지
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• 제16권5호
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• pp.48-53
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• 2004

This study surveys the tension differences between Textec and Vamatex looms and analyses fabric mechanical properties using KES-FB system according to warp and weft tension differences. Fabric is designed as 5 harness satin weave using 150d/48f warp and 200d/384f weft polyester filaments, and is woven by $Omega^{\circledR$-Panter rapier loom by Textec Co.Ltd and P1001es rapier loom by Vamatex Co.Ltd., respectively. These grey fabrics are processed on the same dyeing and finishing processes. Weavability is also analysed by measuring warp tension variation according to the warp position. The relationship between shed amount and the warp tension on one fixed heald frame is surveyed, and the relationship between end breaks and warp and weft tensions is also discussed.

• 대한공간정보학회지
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• 제19권3호
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• pp.23-32
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• 2011

본 연구에서는 소유역을 정방형 격자망으로 형성하고 GIS 데이터처리를 행하여 다양한 지형적인 요소를 각 격자 단위로 해석할 수 있도록 한 다음, 분포형 모형 중 대표적인 $Vflo^{TM}$에 적용하였다. 그리고 모형을 이용함에 있어서 소유역 내에서 공간적으로 상이함을 무시하고 유역의 평균적인 토양함수조건을 적용하는 종전의 연구와 달리, 픽셀 단위로 구성되어 있는 LANDSAT 7 $ETM^+$ 위성영상으로부터 Tasseled Cap 변환을 통해 추출한 토양함수정보 를 모형의 각 격자에 적용하였다. 연구 결과, 소유역에서 토양함수의 공간적인 변화가 분포형 모형의 틀에 잘 부합할 수 있음을 확인할 수 있었다. 또한 영상획득시기의 습윤지수와 10일 선행강우량과의 관계식을 추정하였으며, 이를 통해 구한 가중치의 적용성을 입증할 수 있었다.

• 한국동물학회지
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• 제10권2호
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• pp.18-22
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• 1967

The routine entomological investigations were carried out in the areas of Kaejeon-Myon, OkkuGun, Cholla Pukdo province in 1964 and Sinchang-Myon, Asan Gun, Chungchong Namdo province in 1965, for the better understanding of the behavior of the anpheline mosquitoes especially of the population density , resting , feedign, and breeding habits. The results are as follows : 1. During the investigation , three species of anopheline mosquitoes were recorded ; Anopheles sinensis Wiedmann 1825, A, sineroides Yamada 1935, and A. yatsushiroensis Miyazaki 1951. A . yatsushiroensis Myiyasaki 1951, so far only recorded in Japan, was recorded for the first time in Korea in 1964 ; the site was Kaejong Myon, Okku Gun, Cholla Pukdo province. 2. Anopheles mosquitoes begin to appear from the middle of April and disappear in October. The date of mosquitoes collected by resting place collection in cow shed are three weeks ahead to the night time cow biting collection. 3. Resting places of anopheline mosquitoes are mainly in cow shed and outdoors which provides high humidity and shadow. 4. The population density of a. sinensis sows a peak in late June and early July in cow shed and by cow biting collection respectively, and another small peak in late August and early September. 5, . the biting activity at night is throughout the night from dusk to dawn, sharply decreasing just before dawn. The peak period was different in each months, 2100-2200 hours in June, 2300-2400 in July , 0300-0400 in August , and 2300-2400 in September. 6. The minimum temperature required for the mosquito's biting activity is 15 $^{\circ}C$ and the optimum is between 24-$25^{\circ}C$ : over $25^{\circ}C$ the activity is decreased. 7.A , sinensis appeared to be zoophilic in Sinchang area but 13 times anthrophophilic in Kaejong area than the former. 8. the light attraction of a. sinensis is significantly low in middle June and early August. The parous rate of A. sinensis caught by cow biting collection appeared higher after midnight (2400-0300 hours) with no relation to the peak period of biting activity by month.

• Geomechanics and Engineering
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• 제35권4호
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• pp.395-409
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• 2023

Long-span suspension bridges have tunnel anchor systems to maintain stable cables. More investigations are required to determine how closely tunnel excavation beneath the tunnel anchor impacts the stability of the tunnel anchor. In order to investigate the impact of the adjacent tunnel's excavation on the stability of the tunnel anchor, a large-span suspension bridge tunnel anchor is utilised as an example in a three-dimensional numerical simulation approach. In order to explore the deformation control mechanism, orthogonal tests are employed to pinpoint the major impacting elements. The construction of an advanced pipe shed, strengthening the primary support. Moreover, according to the findings the grouting reinforcement of the surrounding rock, have a significant control effect on the settlement of the tunnel vault and plug body. However, reducing the lag distance of the secondary lining does not have such big influence. The greatest way to control tunnel vault settling is to use the grout reinforcement, which increases the bearing capacity and strength of the surrounding rock. This greatly minimizes the size of the tunnel excavation disturbance area. Advanced pipe shed can not only increase the surrounding rock's bearing capacity at the pipe shed, but can also prevent the tunnel vault from connecting with the disturbance area at the bottom of the anchorage tunnel, reduce the range of shear failure area outside the anchorage tunnel, and have the best impact on the plug body's settlement control.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1403-1406
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• 2005

The present study was undertaken to study the effect of thermal stress on sexual behaviour of superovulated ewes. Fourteen adult Bharat Merino ewes with an average body weight of 29.4${\pm}$2.34 kg were randomly allocated into two groups of 7 each. All the animals were grazed on natural pasture in the morning and evening hours and housed in shed during night. Animals of Group-1 were housed in shed from 10:00 to 16:00 h while the animals of Group-2 were exposed to thermal stress in a hot chamber ($40^{\circ}C$ /6 h/day). All the animals were offered drinking water once a day at 16:30 h. Meteorological observations i.e. dry bulb, wet bulb, minimum and maximum temperature were recorded daily inside the shed as well as in hot chamber throughout the experimental period. For superovulation of animals, standard protocol developed at the Institute, using FSH (Ovagen 5.4 mg in eight injections) and PMSG (200 IU) was followed. Various sexual behaviour parameters (circling, tail fanning, head turning, standing and approaching to ram) and estrus incidence (onset of estrus and estrus duration) were observed in both the groups. The different estrus symptoms were graded subjectively on arbitrary scale of 0-5 where 0 representing no sexual behaviour (0%) and 5 representing maximum intensity in sexual behaviour (100%). Estrus was detected with the help of a marked aproned ram of proven vigor at six hourly intervals. The average percent values for sexual behaviour parameters recorded in Group-1 and Group-2 animals were 53.7${\pm}$3.76 vs. 41.1${\pm}$2.18 for circling, 71.8${\pm}$5.42 vs. 49.0${\pm}$4.41 for tail fanning, 64.7${\pm}$3.30 vs. 44.5${\pm}$4.34 for head turning, 90.1${\pm}$3.16 vs. 75.8${\pm}$4.02 for standing and 63.8${\pm}$4.8 vs. 41.9${\pm}$4.58 for approaching to ram. Animals exposed to thermal stress had significantly lower values of these sexual behaviour parameters. The animals kept in shed exhibited estrus earlier (25.4${\pm}$1.12 h) and duration was higher (37.7${\pm}$1.59 h) as compared to animals exposed to thermal stress i.e. 30.6${\pm}$1.16 h and 31.7${\pm}$3.57 h, respectively. The findings of the study indicate that thermal stress reduces the intensity of sexual behaviour in ewes and may result in failure of the animal to mate and conceive.

• Parasites, Hosts and Diseases
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• 제27권3호
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• pp.203-212
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• 1989

실험실에서 사육한 수종 패류를 이용하여 Echinostoma cinetorchis의 생활환을 형성시키 며 발육과정을 관찰하였다. 성충체(흰쥐에서 얻음)에서 분리한 충란을 배양하여 miracidium을 얻고 제 1중간숙주인 Hippeutis sp. 우렁이에 20개씩 감염시킨 바 58.3%(12개 중 7)는 cercaria 유출 전에 감염사하였고 나머지는 25일 째부터 7∼9일간 cercaria를 유출하였다. 이 cercaria를 수종의 패류에 접촉감염(패당 40∼50마리)시켰더니 피낭유충 형성은 Hippeutis sp.에서 100%(접촉 cercaria에 대한 피낭 비율은 56.7%), Radix auricuzaria coreana 100% (66.4%), Phyla acute 66.7% (37.3%) 및 자연산 Cipangopaludina sp. 50% (8%) 감염으로 전 실험 패류가 피낭유충을 형성하였다. Cercaria는 침입시 노출부인 두부, 족부에 부착한 후 포복하여 외투강 내로 이행하며, 패 체내의 피낭부위는 외투막, 원체강내, 내부 기관 및 조직 사이였다. 그리고 이를 흰쥐에 감염시켜 성충을 검출할 수 있었다. 이상의 결과로 한국에 있어서 E. cinetorchis의 주요 인체 감염원 역할을 할 것으로 믿어지는 논우렁이(Cipnngopaludina sp.)에 있어서 피낭유충 형성을 확인할 수 있었고 이 극구흡충은 타종(특히 E. hortense)과 달리 여러 담수 패류가 제2중간숙주 역할을 하고 있음을 확인하였다.

• Journal of Plant Biotechnology
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• 제29권3호
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• pp.193-198
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• 2002

작약의 약 및 소포자 배양 효율을 향상시키기 위하여 배지 내에 첨가되는 PAA의 농도별 배형성 정도와 배의 형태적 변이 등에 대한 실험을 수행하여 얻어진 결과를 요약하면 다음 과 같다. 작약의 약배양에서 배지 내에 첨가되는 PAA의 농도에 따라 소포자 유래의 배형성률은 다르게 나타났는데 2 mg/L의 PAA가 첨가된 배지에서 배형성률이 가장 높게 나타났으며, PAA의 농도가 증가됨에 따라 배형성를은 낮아진 반면 캘러스 형성률은 증가하는 경향을 나타내었다. 소포자에서 유래된 배의 형태는 PAA의 농도에 따라 큰 변이를 나타내었는데 2개의 자엽을 가진 정상배의 출현빈도는 2 mg/L의 PAA가 첨가된 배지에서 가장 높게 나타났으며 PAA의 농도가 그 이상으로 증가하면 오히려 비정상배의 출현빈도가 높아지는 경향이었다. 작약의 소포자 배양에서도 2 mg/L의 PAA 첨가 배지에서 10일간 전배양된 약을 PAA (2 mg/L)를 함유한 MS액체 배지에 배양했을 때 누출된 소포자 (shed microspore)의 수도 많았고 분열률도 높았으며, 이들 소포자로부터 형성된 배의 수도 가장 많았다.

• 한국해양공학회지
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• 제18권1호
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• pp.7-9
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• 2004

Using the solution to th contour integral of the complex logarithmic function ${\oint}_cIn(z-z_{0})dz$, the following definite integral, derived from the formula to calculate the forces exerted to n circular cylinder by the discrete vortices shed from it, has been evaluated (equation omitted)

• 한국전산유체공학회지
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• 제13권4호
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• pp.39-44
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• 2008

Numerical simulations of laminar flow over a sphere are conducted to investigate the effect of the Reynolds number on the characteristics of vortex shedding. The Reynolds numbers considered are between 300 and 475, covering unsteady planar-symmetric and asymmetric flows. Results show that the unsteady planar-symmetric flow can be categorized into two different regimes: single-frequency regime and multiple-frequency regime. The former has a single frequency component due to periodic shedding of the vortices with the same strength in every shedding cycle, while the latter has multiple frequency components due to cycle-to-cycle variation in the strength of shed vortices with the shedding angle fixed. The multiple-frequency planar-symmetric flow, which is newly found in the present study, occurs at Re=330${\sim}$360 between the single-frequency planar-symmetric flow and the asymmetric flow. On the other hand, the asymmetric flow occurs at Re${\geq}$365, where the vortices shed from the sphere show variation both in strength and shedding angle unlike the planar-symmetric flow. Also, it is shown that the breaking of planar symmetry is closely related to the imbalance of vortical strength between a pair of streamwise vortices.