• Animal cells and systems
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• 제3권2호
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• pp.161-165
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• 1999

Nephila clavata, a golden orb-web spider, was studied at two different field sites with respect to web size, height, and orientation. A majority of spiders at Site 1 (a band of shrub bush) built their webs parallel or nearly parallel to the edge of the bush. Similarly, at Site 2 (near a pond), most webs were aligned with the shoreline of the pond. Among the possible determining factors for the observed patterns of web orientation, wind and light did not appear important. Instead, the movement direction of insect prey appeared largely responsible. Disproportionately more webs faced outside the bush and toward the pond than inside the bush and away from the pond at Site 1 and 2, respectively. Such trend was more apparent for larger spiders with larger webs.

• The Korean Journal of Ecology
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• 제19권2호
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• pp.141-149
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• 1996

This study was to examine the occurrence of geographic song variation and its pattern of transitional direction among bush warbler populations distributed in Korea and Japan, Bush warbler songs (n=283) of 25 males from Cheongwon and Jeju, Korea, and from Chiba, Japan were analyzed. Chiba individuals had more song types and had the higher dominant frequency and longer duration of the introductory whistle portion than Cheongwon and Jeju individuals. In measure of eight song parameters, the parameters constantly showed a decreasing or increasing tendency. The constant tendency showed direction related with the geographic location from Chiba to Cheongwon. The difference in song parameters between Cheongwon and Chiba populations was the greatest in comparison to that of other sets of geographic populations. The degree of discrimination among the three populations was 92.00%. These results indicate that there is a geographic song variation between bush warblers of Japan and Korea, and that the song transition has been directed from Chiba (Japan) through Jeju to Cheongwon (Korea).

• Animal cells and systems
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• 제8권2호
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• pp.89-95
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• 2004

The bush warblers (Cettia diphone) have been recognized to possess two types of songs: a normal song that plays roles in attracting mate and territorial defense, and an anomalous song. The present study suggests that the anomalous song functions as an alarm signal as well as other unknown signals. Field observations and playback experiments on the anomalous song of bush warbler were conducted in order to investigate the contextual information that occurred between sender and receiver. In the field observation, the males frequently emitted anomalous songs to potential predators. The males responded with an anomalous song to stuffed potential predators. The distance from where the anomalous song occurs to the stimulating source varied depending upon the kinds of stimulus. The males of bush warbler possibly show different responses to the anomalous song depending on the level of danger. When the anomalous song was played back to terrestrial males and females, no distinctive behavior was observed. The anomalous song may be sung to defend the territory against predators or to distract invaders from the nest and female because the male and female behaviors were related with the anomalous song and its phonetic characteristics.

• Journal of Plant Biology
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• 제10권1_2호
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• pp.36-40
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• 1967

1. The effect of the pH value on P32 absorption of leaves of three forest trees under the water culture is investigated. 2. The degree of the P32 absorption to the pH value is quite different in each forest tree. 3. The phosphorus contents are proved higher in the leaves of Quercus accutissima(the saw shaped oak) than in the leaves of Pinus densiflora(the red pine) and Lespedeza bicolar (bush clover). 4. Larger contents of phosphorus are found in acidity plots than in alkalinity. The leaves of treated plot of the pH 4 (red pine), of the pH 5.0 (bush clover), and of the pH 5.0-6.5 (saw shaped oak) have a higher nutrient capital as indicated by P32 compared with that of the other pH values. 5. It is also noticed that P32 absorption capacity is decreased with the higher pH values. 6. The content of P of leaves shows the lowest value in the plot of the pH 6.5 (pine), of the pH 7.5(bush clover), and of the pH 9.0(saw shaped oak). It is also noticed that the red pine is to do very well in acid cultivation and then follow bush clover and saw shaped oak in the order.

• 한국동물학회지
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• 제38권4호
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• pp.443-448
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• 1995

충북 청원군 일대에서 휘파람새 6 개체에 대하여 군집내 인 청원군집의 song과 군집외 인 제주개체의 song을 이용하여 playback실험을 실시하였다. 실험의 대상개체는 모두 다두 군집의 song에 대하여 강한 반응을 보였으나 군집 사이에 대하여 통계적으로 의미 있는 차이를 나타내지는 않았다. 이러한 결과는 청원군집내의 개체간의 먼 간격으로 인하여 이웃 개체간의 적은 상호작용에서 기인되어지는 것으로 판단된다. Song의 부분들이 song의 인식에 기여하는 정도를 파악하기 위하여, 휘파람새 song의 whistle 부분과 complex syllsble 부분을 이용하여 playback실험을 실시하였다. Complex syllable 부분에 대한 반응의 정도가 whistle 부분에 비하여 의미 있게 높았으며, 이러한 것은 song의 특정한 부분이, complex syllable, 개체의 song인식에 필요한 주된 정보를 담고 있다는 'releaser '가설을 지지하는 결과로 나타났다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1003-1008
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• 2007

Compliance effect consideration method for real-time multibody vehicle dynamics is proposed using quasi-static analysis. The multibody vehicle model without bush elements is used based on the subsystem synthesis method which provides real-time computation on the multibody vehicle model. Reaction forces are computed in the suspension subsystem. According to deformation from the quasi-static analysis using reaction forces and bush stiffness, suspension hardpoint locations and suspension linkage orientation are changed. To validate the proposed method, quarter car simulations of McPherson strut and multilink suspension subsystems. Full car bump run simulations are also carried out comparing with the ADAMS vehicle model with bush elements. CPU times are also measured to see the real-time capabilities of the proposed method.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 추계학술발표대회 논문집
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• pp.110-113
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• 2002

As a preliminary study for the three dimensional failure analysis of composite joints, the three dimensional stress analysis on a pin-loaded unidirectional-fabric hybrid composite joints are performed. The contact and frictions between composite plate and metal bush are considered in the finite element method by NASTRAN. Experiments are conducted to validate the accuracy and feasibility of the finite element technique for 25 specimens with 5 different geometries. The finite element and experimental results show the bush cap induces the unsymmetric deformation, stress distribution, and failure behavior through the thickness. The experiment also shows the failure loads are higher in the joint with bush cap than without it.

• 대한기계학회논문집A
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• 제32권2호
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• pp.162-169
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• 2008

Compliance effect consideration method for real-time multibody vehicle dynamics is proposed using quasi-static analysis. The multibody vehicle model without bush elements is used based on the subsystem synthesis method which provides real-time computation on the multibody vehicle model. Reaction forces are computed in the suspension subsystem. According to deformation from the quasi-static analysis using reaction forces and bush stiffness, suspension hardpoint locations and suspension linkage orientation are changed. To validate the proposed method, quarter car simulations of McPherson strut and multilink suspension subsystems are performed. Full car bump run simulations and fish hook handling test simulations are also carried out comparing with the ADAMS vehicle model with bush elements. CPU times are also measured to see the real-time capabilities of the proposed method.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.244-249
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• 1997

Internal and external heat sources will cause to deform to machine elements in the contact joint of structure,which results in the change of contact pressure distribution different from initial assembly. Heat induced variations of contact pressure will change the static and dynamic properties such as contact stiffness,damping as well as contact heat conduction in the structure. In order to design and control the intelligent machine tool operating in variant conditions more sophisticatedly, the good prediction for the changes of prescribed propeties are strongly required especially in the contact elements adjacent to the rotational or linear bearing This paper presents some computational and experimental results in regard to static and dynamic characteristics of the press-fitted bush and shaft assembly which is a model of the bearing innerrace and shaft assembly. In the condition of heat generation on the outer surface of the bush,the effects of changes in the negative clearance and the heat flux on pressure distribution and dynamic properties are investigated. Results of this study show that the edge effect of the bush and the initial clearance have effects on the transient dynamic characteristics significantiy.

• 한국기계가공학회지
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• 제16권4호
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• pp.104-112
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• 2017

In the sand casting process, the flow of liquid metal affects the quality of casting products and their die life. To determine the optimal bush part design process, this study performed various analyses using commercial finite element analysis S/W. The simulation focused on the molten metal behaviors during the mold filling and solidification stages of sand casting. This study aims to develop methods to reduce the cost and increase the tool life of the continuous hot zinc plating roll.