• 한국응용곤충학회지
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• 제31권1호
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• pp.37-44
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• 1992

한국, 중국, 필리핀산 흰등멸구의 계량형태학적 차이를 분석하기를 위하여 총 89개 부분의 형태적 특징(촉각 34, 다리45, 주둥이10)을 조사하고 계량형태적 분석을 위하여 정준 판별분석법을 이용하였다. Scatter plot diagram 상에서 3개 집단의 중심점은 분리현상이 뚜렷하였고 그 정도는 단시형 암컷에서 크게 나타났다. Mahalanobis distance(MD)는 단시형 암컷의 경우 3개 집단 모두 5%에서 유의성이 있었고, 장시형 암컷의 경우 MD는 중국산 대 필리핀산, 한국산 대 필리핀산이 각각 0.1%, 1%에서 유의성이 있었으나, 중국산 대 한국산은 유의성이 없었다.

• The Korean Journal of Ecology
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• 제13권4호
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• pp.331-342
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• 1990

Analysis of vegetation on the pavements and under the trees of streets in Seoul city were investigated from July to November 1989. All of the vascular herbs were 9 orders, 13 families, 30 genera, 37 species and 1 forma. Species diversity and evenness index were higher on the pavements than under the trees of streets. Eragrostis multicaulis with C-4 pathway was a dominant species, and next orders of importace values were Eleusine indica(C-4), Digitaria sanguinalis(C-4), Taraxacum officinale(C-3) and Erigeron annus(C-3). On the pavements and under the trees of streets, light intensity and surface temperature were very high, Also, these sites were affected by many kinds of human interferences. Therefore, it was an example of adaptation to specific ecological environments that C-4 plats were more dominant than C-3, growth forms of C-3 plants were rosette or prostrate, and annual or biennial plants were distributed in these studied sites. Generally, fruits types were grains, achens and capsules. Seeds were very small and some had appendages such as pappus.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.189-192
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• 2002

In this paper, the submarine model, called DARPA SUBOFF model, has been numerically analyzed to investigate the aerodynamic forces variation in terms of angle of attacks and yaw angles. The SUBOFF model is consisted of the three parts : axisymmetric body, fairwater, and four symmetric stern appendages. Three dimensional unsteady incompressible Wavier-Stokes equation was used on curvilinear multi-block grid system. To validate the present code, the SUBOFF tare hull and an ellipsoid at angle of attacks of $10^{\circ}\;and\;30^{\circ}$ were simulated and a good agreement with experiments was obtained. After the code validation, the flows over SUBOFF model were simulated at three different angle of attacks and yaw angles. The variation of aerodynamic forces in terms of angle of attack and yaw angle were calculated. Also, to understand the flow features around a submarine with variation of yaw and attack angle, the pressure contours and streamlines were plotted.

• Animal cells and systems
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• 제8권1호
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• pp.1-12
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• 2004

All copepodid stages and free-swimming adults of Ergasilus hypomesi Yamaguti collected from plankton samples from a brackish lake in Korea are described. The antennule remains a four-segmented appendage until copepodid V. The antenna of copepodid I carries a vestigial exopod. Sexual dimorphism first appears at copepodid IVwhose males bear primodial maxillipeds. Leg 5 also is sexually dimorphic from copepodid IV onwards, with its free segment bearing three setae in the female and two setae in the male. Morphological features of some appendages appearing during copepodid development are discussed. It is noticed that the early copepodids of the Ergasilidae show the characteristic setation on the biramous legs and proximal segments of the antennule.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1216-1221
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• 2000

Thermally induced vibration response of composite thin walled beams is investigated. The thin-walled beam model incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, 'rotary inertia' and anisotropy of constituent materials. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferentially uniform system(CUS) configuration are exploited in connection with the structural coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. A coupled thermal structure analysis that includes the effects of structural deformations on heating and temperature gradient is investigated.

• 한국지구과학회지
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• 제23권1호
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• pp.30-37
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• 2002

Leptostrobus myeongamensis sp. nov. is newly described from the well-preserved but broken material occurring in the Upper Triassic Amisan Formation of the Nampo Group in Korea. This species is characterized by its lateral appendages of cone axis, each consisting of a rounded capsule and small scale leaf, and by its cone base covered with small scale leaves, the same size as in cone axis. This species is the first record from the Mesozoic strata in Korea.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.824-831
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• 2005

A model test was carried out, in order to verify the hydrodynamic performances of public 30 feet class sailing yacht. In the initial design stage, the performances and the running attitude of sail yacht including the hull form and sail plan, appendages were estimated by VPP, from which made the representative test conditions. A new experiment system such as captive model device was composed because the running attitude could be changed by wind conditions. The test results show that the minimum resistance is generated in the heeling 20 degree, which was expected in the initial design stage. It is thought to be the useful informations that the keel has an effects on hydrodynamic forces and resistance differences between the upwind and the downwind condition. Also this paper is associated with the state-of-the-art of calculating sailing yacht performance as this is performed in velocity prediction program (VPP). The VPP results shows a typical shape of a sailing yacht and the designed yacht has the best performance at 120 degree angle of true wind with 20 knots.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.303-310
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• 2002

The bending vibration and thermal flutter instability of spacecraft booms modeled as circular thin-walled beams of closed cross-section and subjected to thermal radiation loading is investigated in this paper. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferantially uniform system(CUS) configuration are exploited in connection with the structural flapwise bending-lagwise bending coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. The numerical simulations display deflection time-history as a function of the ply-angle of fibers of the composite materials, damping factor, incident angle of solar heat flux, as well as the boundary of the thermal flutter instability domain. The adaptive control are provided by a system of piezoelectric devices whose sensing and actuating functions are combined and that an bonded or embedded into the host structure.

• 한국항공운항학회지
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• 제14권4호
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• pp.31-37
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• 2006

In this paper, an experimental study on the robust input shaping for control of the residual vibration of flexible structures has been investigated. Two approaches has been used for the robustness of input shaping: the first method is to increase the number of impulses, and the other includes an EI shaper using vector diagram. The input case designed by the application of the above methods has been applied to a control problem involving residual vibration of a rotating hub with two flexible appendages. It has been found by a series of experiments that the input shaper designed in this paper works well for the residual vibration control of the flexible structure.

• International Journal of Aeronautical and Space Sciences
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• 제16권4호
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• pp.602-613
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• 2015

As one of the mission payloads to be verified through the cube satellite mission of Cube Laboratory for Space Technology Experimental Project (STEP Cube Lab), we developed a hinge driving separation nut-type holding and releasing mechanism. The mechanism offers advantages, such as a large holding capacity and negligible induced shock, although its activation principle is based on a nylon cable cutting mechanism triggered by a nichrome burn wire generally used for cube satellite applications for the purpose of holding and releasing onboard appendages owing to its simplicity and low cost. The basic characteristics of the mechanism have been measured through a release function test, static load test under qualification temperature limits, and shock measurement test. In addition, the structural safety and operational functionality of the mechanism module under launch and on-orbit environments have been successfully demonstrated through a vibration test and thermal vacuum test.