• 한국자동차공학회논문집
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• 제18권5호
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• pp.115-123
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• 2010

Cool-down performance after soaking is important because it affects passenger's thermal comfort. The cooling capacity of HVAC system determines initial cool down performance in most cases, the performance is also affected by location, and shape of panel vent, indoor seat arrangement. Therefore, optimal indoor designs are required in developing a new car. In this paper, initial cool down performance is predicted by CFD(computational fluid dynamics) analysis. Experimental time-averaging temperature data are used as inlet boundary condition. For more reliable analysis, real vehicle model and human FE model are used in grid generation procedure. Thermal and aerodynamic characteristics on re-circulation cool vent mode are investigated using CFX 12.0. Thermal comfort represented by PMV(predicted mean vote) is evaluated using acquired numerical data. Temperature and velocity fields show that flow in passenger's compartment after soaking is considerably unstable at the view point of thermodynamics. Volume-averaged temperature is decreased exponentially during overall cool down process. However, temperature monitored at different 16 spots in CFX-Solver shows local variation in head, chest, knee, foot. The cooling speed at the head and chest nearby panel vent are relatively faster than at the knee and foot. Horizontal temperature contour shows asymmetric distribution because of the location of exhaust vent. By evaluating the passenger's thermal comfort, slowest cooling region is found at the driver's seat.

• 대한족부족관절학회지
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• 제8권2호
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• pp.191-194
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• 2004

Purpose: Anatomic configuration of the ankle joint is useful information during various ankle procedures. This study was prospectively designed to investigate the sagittal inclination pattern of the ankle joint. Materials and Methods: Lateral standing ankle radiographs from one-hundred people (age: $17{\sim}68$, M:F=45:55) and magnetic resonance (MR) sagittal ankle images from twenty-four people (age: $16{\sim}65$, M:F=14:10) were studied. Post-traumatic, arthritic, or grossly deformed ankles at any reason were excluded. The posterior inclination angle (PIA) of the distal tibia was measured and compared between the lateral and the medial segment. Results: On plain radiographic data, the average PIA of the distal tibia was $6.14^{\circ}{\pm}3.56^{\circ}$ (range $0^{\circ}$ to $14^{\circ}$) in the lateral segment and $13.16^{\circ}{\pm}3.05^{\circ}$ (range $6^{\circ}$ to $22^{\circ}$) in the medial segment. On MR imaging data, the average PIA of the distal tibia was $5.08^{\circ}{\pm}4.26^{\circ}$ (range $1^{\circ}$ to $10^{\circ})$ in the lateral segment and $10.16^{\circ}{\pm}4.87^{\circ}$(range $5^{\circ}$ to $17^{\circ}$) in the medial segment. The PIA between two segments was significantly different. Conclusion: The sagittal configuration of the medial area ankle joint and the lateral area ankle joint has difference in the degree of posterior inclination and shape of curvature.

• 한국패류학회지
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• 제27권3호
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• pp.253-259
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• 2011

Boring behaviour and drilling mechanism were investigated by visual observations. In this study, of two kinds of holes (the outer and inner holes) which are formed by drilling of boring gastropod Lunatia fortunei (Naticidae), the diameters of the outer holes are broader and larger than those of the inner holes, and their holes look like the crater in shape, as seen in all valves of bivalves bored by Naticidae species. Two kinds of glands (the accessory boring gland and accessory salivary gland) on the foots of boring gastropods have been investigated. Of them, it has been confirmed that only the accessory salivary glands on the foots secreted sulphuric (acidic) components in the mucus (secretion), while the accessory boring glands on the foots did not secrete their components. In this study, we confirmed that L. fortunei possess the accessory boring gland on the foot, as seen in most species in Naticidae. Accoeding to the results of the experiment of the blue litmus paper tests of the mucus (secretions) secreted from the accessory boring gland the color of the blue litmus paper did not turn red in color because chemical components of mucus (secretion) secreted from the accessory boring gland on the foot of L. fortunei (boring gastropod) were not acidic components. It is supposed that the mucus, which is secreted from the accessory boring gland, contained gelatin-like substances or enzymes without acidic components, as already reported in Naticidae species. Therefore, these substances may be involved in softening the surface of the valves of M. veneriformis. Consequently, it is assumed thar L. fortunei bores holes through the shells of molluscs by means of following 3 methods: (1) a softening of the calcareous shells of M. veneriformis with chemical secretions (including gellatin-like substances or enzyme except for acidic components) from the accessory boring glands, (2) mechanical rasping with the radula, (3) a combination of both. In this study, particularly, acidic components, which are involved in softening the surface of the shells, are not associated with the boring mechanism of L. fortunei because chemical acidic components were not detected in the mucus (secretion), as found in Naticidae species.

• 한국어류학회지
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• 제26권4호
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• pp.274-280
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• 2014

강도다리(Platichthys stellatus)의 정자는 대부분의 경골어류에서와 같이 첨체를 가지고 있지 않는 구형의 핵, 짧은 중편 및 꼬리를 가진 전형적인 수중형의 정자 형태를 하였다. 정자의 미세구조는 전자밀도가 높은 염색질 부위를 가지는 핵과 핵 기부에 위치한 깊이 함입된 핵와(nuclear fossa) 그리고 그 속에 기부 중심립과 말단부 중심립이 포함되어 있었다. 두 중심립은 90도의 각도로 배열되어 있었으며, 미토콘드리아는 중편 세포질에 배열되어 있으며 핵의 후반부와 꼬리의 기부를 둘러 싸고 있었다. 꼬리는 축사와 2개의 lateral ribbon로 구성되어 있었다. 이러한 특징들은 가자미류의 공유형질로 나타났다. 그러나 미토콘드리아의 수와 모양, 핵와의 모양과 크기에서는 종 특이적 특징을 나타내었다. 특히 강도다리 정자의 가장 큰 구조적 특징은 basal foot, rootlet 그리고 alar sheets로 구성된 기저체이었다. 이 구조의 형태적 특징은 다른 종들 사이에서 아주 다양하게 나타내었다. 이러한 구조는 가자미목의 계통적 관계를 연구하는데 매우 중요한 형질로 여겨진다.

• 한국운동역학회지
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• 제23권2호
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• pp.117-123
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• 2013

The purpose of this study was to provide data to increase the success rate of penalty kicks through quantifying the shape of skilled kicks by performing a kinematic analysis on the change of movement during the kicking phase which the goalkeeper uses as a vital clue. Three high definition video cameras(GR-HD1KR, JVC, Japan) were used for the study and 18 reflective markers were attached to the body joints. Corners of the goal, difficult for goalkeepers to block, were set as aims and 1 m by 1.2 m targets were installed. Each subject had five sets of kicks at random, and the analysis was done on the movements that hit the target. Time, speed of the right lower limb's center of mass, joint angle, and angular velocity were chosen as factors and the results of the analysis showed statistical significance. The player taking a penalty kick should train to avoid leaning one's body towards the kicking direction and change the angle of the right foot right before the impact to decide the direction of the ball. The goalkeeper can increase the save success rate by studying the angle of the kicker's body and the right foot as well as the timing of the kick.

• 한국자원식물학회지
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• 제16권1호
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• pp.89-98
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• 2003

본 연구에서는 Atractylodes속과 혼용되는 Atractylis속 6분류군의 화분을 광학현미경과 주사전자현미경으로 관찰하였다 본 속의 화분은 단립(monad)으로, 극축의 길이는 46.5-66.7$\mu\textrm{m}$, 적도면의 나비는 43.6-60.47$\mu\textrm{m}$이 었다. 발아구는 3공구형 (tri-colporate)으로서 , 구구(colpus)의 길이는 19.6-29.1 $\mu\textrm{m}$, 나비는 7.3-11.0$\mu\textrm{m}$이 었고, 공구의 직경 은 6.4-10.6$\mu\textrm{m}$ 이었다. 화분벽은 외표벽 (ektexine)은 기저층(foot layer)과 원주층(columellae), 피복층(tectum)으로 구성되고, 두에는 5.2-8.3$\mu\textrm{m}$이었다. 화분의 표면 돌기는 자상(echinate)으로서 길이가 1.4-5.8$\mu\textrm{m}$이었으며, 단위면적당(No./20$\mu\textrm{m}$$^2$) 분포는 6-33개 이었다 본 연구에서 취급된 분류군들의 화분, 특히 Atractylis arabica, A. aristata, A. carduus, A. microcephala의 화분형 태는 Atractylodes속의 화분과 매우 유사하였으며, 따라서 화분에 관련된 형질은 두 속을 구분하는 식별형질로 적용할 수 없었다. 그러나 화분에 관련된 형질이 Atractylodes속에서는 화분의 크기만이 속내 분류군간의 식별형질로서 기여도가 적은 반면, Atractylis속에서는 화분의 크기뿐만 아니라 형태 및 표면무늬와 자상돌기의 크기 등에 있어서 분류군간 의 식별형질로서 적용되어 분류학적 기여도가 다소 큰 것으로 판단된다. 또한 본 연구에서 취급된 분류군 중 A. cancellata와 A. prolifera는 나머지 분류군들과 달리 자상돌기가 작고 적도면상이 긴 특징은 본속의 화분의 진화경 향성을 파악하는데 매우 유용하였다.

• 환경생물
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• 제23권2호
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• pp.157-162
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• 2005

한국산 산개구리류 3종의 분류학적 형질을 명확히 하기 위하여 형태학적, 계량형태학적 방법을 이용하여 한국산 산개구리류 3종(북방산개구리, 계곡산개구리, 아무르산개구리)과 일본산 산개구리류 1종(R. tsushimensis)을 비교 분석하였다. 형태학적 비교 분석결과, 산개구리류는 손가락 끝과 발가락 끝의 모양, 아래턱에 형성된 반문의 발달유무, 윗입술선의 유무, 물갈퀴의 발달 정도, 서구개치열의 형태 등이 차이가 있는 것으로 확인되었으며, 계량형태학적 분석을 통하여 고막의 직경과 발길이의 차이를 확인할 수 있었다. 따라서, 이러한 형태학적, 그리고 계량형태학적 특징은 한국산 산개구리류를 동정하는데 매우 유용한 형질이라고 생각된다.

• 한국지역사회생활과학회지
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• 제23권3호
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• pp.221-231
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• 2012

To find the differences between the real somatotype and the ideal somatotype, WHR(Waist to Hip Ratio), WCR(Waist to Chest Ratio), and body cathexis were analysed by using ANOVA test, Duncan's multiple range test, and $x^2$ test. Fashion image sought by female collegians was surveyed, too. The results were as follows. WHRs in slim, usual, fat body type were 0.75, 0.76, and 0.83 and WCRs were 0.77, 0.81, 0.80. The respondents who considered themselves to be overweight recognized themselves to be fatter than their real weight. They were not satisfied with their bust girth in slim body type, thighs and calves in usual body type, and all parts except for foot length, hand length and arm length in fat body type. 60% of the thin people considered their body hourglass shape, 30.4% of regular people recognized their body triangle type, 43.8% of fat people thought their body was round form. They thought current ideal body size was bigger in height and bust girth and smaller in waist girth and hip girth, and weight than real body size. Also they responded ideal body shape was an hourglass type independent of somatotype. The pursuit of clothing image was that 45.5% of female collegians were fashionable and raffine and 10.4% of female collegians was elegant and graceful. Among the body area, body parts that may have an effect on body image were body length in 13.1% of the respondents, waist girth in 10.7% of the respondents, and hip girth in 10.0% of the respondents.

• 대한기계학회논문집A
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• 제34권9호
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• pp.1145-1151
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• 2010

본 논문은 형상기억합금 와이어에 의해 구동되는 점핑로봇에 대한 연구로서 기구의 설계와 컴퓨터 시뮬레이션을 포함하고 있다. 인간과 같은 척추동물 하지 근골격계의 구조와 기능을 모방한 구조의 점핑 기구를 설계하였다. 점핑 기구의 각 다리는 대퇴부, 정강이, 발의 세 부분으로 구성되고, 점핑에 필수적인 단일관절근육인 대둔근, 양관절근육인 대퇴직근과 비복근을 포함하는 구조이다. 각 근육을 형상기억합금 와이어로 대체한 컴퓨터 모델로 시뮬레이션한 결과, 로봇의 최대 점핑 높이가 로봇 신장의 약 4 배임을 확인하였다. 또한 구조가 보다 단순화된 로봇 모델과 점핑 성능을 비교하였고, 그 결과 근골격계를 모방한 모델이 점핑 높이 면에서 3.3 배 우수한 것으로 나타났다. 이러한 컴퓨터 시뮬레이션을 통하여 형상기억합금이 소형 점핑로봇의 작동기로 사용하기에 적합함을 확인하였다.

• Structural Engineering and Mechanics
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• 제16권5호
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• pp.519-531
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• 2003

Piezoelectric actuators have long been recognised for use in aerospace structures for control of structural shape. This paper looks at active control of the swept shock wave/turbulent boundary layer interaction using smart flap actuators. The actuators are manufactured by bonding piezoelectric material to an inert substrate to control the bleed/suction rate through a plenum chamber. The cavity provides communication of signals across the shock, allowing rapid thickening of the boundary layer approaching the shock, which splits into a series of weaker shocks forming a lambda shock foot, reducing wave drag. Active control allows optimum control of the interaction, as it would be capable of positioning the control region around the original shock position and unimorph tip deflection, hence mass transfer rates. The actuators are modelled using classical composite material mechanics theory, as well as a finite element-modelling program (ANSYS 5.7).