• 우주기술과 응용
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• 제2권1호
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• pp.41-51
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• 2022

큐브위성은 기존의 인공위성과 마찬가지로 지구 관측뿐만 아니라, 우주탐사 분야에도 폭넓게 활용되는 인공위성 플랫폼이다. 또한 우주 공간물리현상을 관측하기 위한 자기장관측 임무에서도 다양한 형태로 제작되어 활용되고 있다. 자기장 측정의 경우, 일반적으로 위성의 자기 교란을 최소화하기 위해 자기장측정기가 위성 몸체로부터 멀리 떨어져 있다. 그러나 큐브위성과 같은 작은 위성의 경우 공간적인 제약으로 인해 자기장 센서의 위치 설정이 제한적이다. 이에 이 논문에서는 큐브위성에서 생성된 자기장 간섭을 추정하여 자기장 측정의 신뢰성에 얼마나 영향을 줄 수 있는지 분석하였다. 주요 잡음원으로는 상대적으로 높은 소비전력을 가진 반작용 휠과 자기 토크로드를 대상으로 조사하였다. 이러한 부품의 자기 쌍극자 모멘트는 제조업체의 데이터 시트에 제공된 정보를 사용하였다. 외부 자기장이 없는 공간에서 3 U 큐브위성 중간에 위치한 자기 토크로드의 잔류 모멘트의 영향은 위성의 몸체 최 외곽 끝에서 약 36,000 nT까지 나타날 수 있음을 확인했다. 또한, 1 nT 미만의 정확한 자기장 측정의 임무라면, 자력계는 위성 본체에서 약 0.6 m 반경 거리 외곽에 있어야 함을 알 수 있었다. 이러한 분석 방법은 자기장 측정을 수행하기 위해 CubeSat을 설계할 때 자기 청결도 분석의 중요한 역할이 될 것으로 기대한다.

• 한국자동차공학회논문집
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• 제10권1호
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• pp.216-233
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• 2002

Due to the environmental problems of fuel consumption and vehicle emission, etc., automotive makers are trying to reduce the weight of vehicles. The most effective way to reduce a vehicle weight is to use lighter materials, such as aluminum and plastics. Aluminum Intensive Vehicle(AIV) has many advantages in the aspects of weight reduction, body stiffness and model change. So, most of automotive manufacturers are attempting to develop AIV using Aluminum Space Frame(ASF). The weight of AIV can be generally reduced to about 30% than that of conventional steel vehicle without the loss of impact energy absorbing capability. And the body stiffness of AIV is higher than that of conventional steel monocoque body. In this study, Aluminum Intensive Vehicle is developed and analyzed on the basis of steel monocoque body. The energy absorbing characteristics of aluminum extrusion components are investigated from the test and simulation results. The crush and crash characteristics of AIV based on the FMVSS 208 regulations are evaluated in comparison with steel monocoque. Using these results, the design concepts of the effective energy absorbing members and the design guide line to improve crashworthiness for AIV are suggested.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.194-199
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• 2005

Body-on-frame type vehicle has a set of frame bushes which are installed between body and frame fur vibration Isolation. Such frame bushes are important vibration transmission paths to passenger space. In order to reduce the vibration level of passenger space, therefore, the change of complex stiffness of the frame bushes is more efficient than modification of other parts of the vehicle such as body, frame and suspension. The purpose of this study is to reduce the vibration level for ride comfort by optimization of complex stiffness of frame bushes. In order to do this end, simple finite element vehicle model was constructed and the complex stiffness of frame bushes was set to be design variable. Objective function was defined to reflect passenger ride comfort and genetic algorithm and sub-structure synthesis were applied for minimization of the objective function.

• 천문학회보
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• 제43권1호
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• pp.46.3-47
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• 2018

We present a general N-body exasolar system simulator in anticipation of upcoming searches for exoplanets and even exomoons by next generation telescopes such as James Webb Space Telescope. For habitable zones, traditionally defined by temperature, we here address the essential problem of dynamical stability of planetary orbits. Illustrative examples are presented on P-type orbits in stellar binary systems, that should be fairly common as in Kepler 16b. Specific attention is paid to reduced orbital lifetimes of exoplanets in the habitable zone by the stellar binary, that is propoesed by Maurice van Putten (2017). Especially, we focused on a classic work of complex three-body problem that is well known by Dvorak(1986). We charge his elliptic restricted three-body problem to extend unrestricted three-body problem to look into dynamical motions in view of circumbinary planet, furthermore, we suggest that opposite angular orientation of the planet is relative to the stability of orbits. In here, counter-rotation case is relatively more faster than co-rotation case for being stable. As a result, we find that various initial conditions and thresholds to approach dynamical stability and unstability with unexpectable isolated islands over enormous parameter space. Even, superkeplerian effect of binary is important to habitability of the exoplanet and we can verify that superfaster binary doesn't effect on th planet and increases survivality of planet around the binary.

• 한국의류학회지
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• 제47권3호
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• pp.531-543
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• 2023

Unlike a still body in a photograph, the concept of time applies to a moving body wearing clothes. Clothes change shape according to movement, and multidimensional formative observation elements are required to perceive this. Thus, the purpose of this research is to develop a system for observing body movements and clothing. This experimental study was designed based on embodiment research. The first stage of the study derived body movement and clothing observation items from theory. In the second stage, 11 fashion personnel participated in experimental research to verify the observation items and identify those that needed correction or supplementation. The results showed that body movement and clothing observation items can be classified as follows: large moving bodies, moving clothes, body and clothes movement, and body and clothes space. The observation system for body movement and clothes presented can be used to construct the formation of moving clothes.

• 한국의류학회지
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• 제32권2호
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• pp.340-347
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• 2008

A prototype of 3D clothing design system with a direct pattern development function was suggested, reflecting intuitive design functions and design modifications while considering the fit of clothing patterns with the 3D human body in the virtual 3D space. The research method was as follows. Clothing models were created using a 3D design tool, 3ds max on the surface of 3D human body model made by scanning an actual human body. 3D illustrations were completed by revising the fit and sizing of the human body and clothing models. 2D T-shirt pattern was produced 3D illustrations using from a 3D scanning data modeling solution RapidForm 2004, a 2D conversion program for 3D data called 2C-AN, and Yuka CAD. As a result, the following conclusions were made. The fit of the clothing and human body can be adjusted by reflecting individual body figure characteristics and 3D illustrations over the actual 3D body model. Furthermore, intuitive design support functions were intensified overcoming the weak point of existing 3D clothing design system by developing the direct clothing design in the virtual 3D space. 3D illustration design modifications can be directly reflected on clothing patterns from 3D illustrations by 3D clothing design system developed in this study.

• 영어영문학
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• 제58권4호
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• pp.701-721
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• 2012

This paper aims to revisit William Faulkner's Absalom, Absalom! by focusing on the corporeal body and its role in dismantling the Southern ideology of white patriarchy. The latter, which is represented by Thomas Sutpen and his attempt to establish a white male dynasty, is a symbolic space in which the corporeal body turns into a symbolic one through the process of inscribing social ideologies on it. However, this symbolic space is also a contending site between the two bodies. The symbolic body of Sutpen cannot entirely erase its corporeal traces, and therefore the corporeal body, which is buried but nonetheless existent, threatens to undermine rules and premises of the symbolic order. Given that, this paper approaches Faulkner's critique of the Southern white patriarchal ideology from the tension that the corporeal body and the symbolic body create. The 'flesh' roughly corresponds to racial and sexual otherness, namely black flesh and the homoerotic desire of male body. Although they-as the matter of race and that of gender - function in different levels of signification, they still share a common purpose in revealing the logical paradox within Sutpen's symbolic order. The idea of pure whiteness that Sutpen subscribes to is a concept that prerequisites the existence of blackness. Likewise, his idea of male homosociality based upon patriarchal legacy stands precariously on the verge of disintegrating into homoetoricism. As internal otherness that Sutpen's symbolic order cannot fully incorporate, the corporeal body functions to indicate the limitation of Sutpen's Design and its body-signification process.

• Journal of Korean Neurosurgical Society
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• 제57권3호
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• pp.185-191
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• 2015

Objective : In order to provide normal values of the pediatric sub-axial cervical spinal canal and vertebral body growth pattern using computed tomographic scans, a total of 318 patients less than 10 years old were included. Methods : The growth of the vertebral body and canal space was investigated using four different age groups. The Torg ratio (TR) was calculated and all patients were classified into a low TR group and a high TR group according to a cutoff value of 1.0. To account for spinal curvature, the C3-7 angle was measured. Results : Very little axial expansion and growth in height were observed (2.9 mm and 3.4 mm, respectively), and the spinal canal increments (1.8 mm) were much smaller than the dimensions of the vertebral body. The mean TR values were $1.03{\pm}0.14$ at the C3 vertebral level, $1.02{\pm}0.13$ at C4, $1.05{\pm}0.13$ at C5, $1.04{\pm}0.13$ at C6, and $1.02{\pm}0.12$ at C7 in all patients. The mean sub-axial angle (C3-7) was $7.9{\pm}10.6^{\circ}$ (range: $-17-47^{\circ}$). Conclusion : The upper sub-axial spinal canal continuously increased in size compared to the lower sub-axial spine after 8 years of age. Considerable decrements in the TR was found after late childhood compared to younger ages. Generally, there were no significant differences between boys and girls in vertical length of the cervical vertebrae. However, the axial dimension of the vertebral body and the spinal canal space varied according to gender.

• Journal of Astronomy and Space Sciences
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• 제31권3호
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• pp.187-197
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• 2014

We have investigated the dynamical stability of the proposed companions orbiting the Algol type short-period eclipsing binary SW Lyncis (Kim et al. 2010). The two candidate companions are of stellar to substellar nature, and were inferred from timing measurements of the system's primary and secondary eclipses. We applied well-tested numerical techniques to accurately integrate the orbits of the two companions and to test for chaotic dynamical behavior. We carried out the stability analysis within a systematic parameter survey varying both the geometries and orientation of the orbits of the companions, as well as their masses. In all our numerical integrations we found that the proposed SW Lyn multi-body system is highly unstable on time-scales on the order of 1000 years. Our results cast doubt on the interpretation that the timing variations are caused by two companions. This work demonstrates that a straightforward dynamical analysis can help to test whether a best-fit companion-based model is a physically viable explanation for measured eclipse timing variations. We conclude that dynamical considerations reveal that the proposed SW Lyncis multi-body system most likely does not exist or the companions have significantly different orbital properties from those conjectured in Kim et al. (2010).

• 한국음향학회지
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• 제22권8호
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• pp.680-686
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• 2003

디지털 도파관 모델은 악기의 물리적 모델링에 사용되는 일반적인 방법이다. 디지털 도파관 모델에서 파동의 움직임은 시간 또는 공간을 기준으로 해석 가능하다. 음의 샘플링이 시간을 기준으로 이루어지므로 악기 모델은 시간에 의한 파동의 움직임으로 묘사되는 것이 일반적이다. 본 논문에서는 현에 대한 공간 기준의 디지털 도파관 모델에 악기 몸체 모델을 추가해 악기 음을 합성하였다. 그렇게 함으로써 합성 음의 음질을 향상시키고 악기 모델의 음색 조절 변수들을 효과적으로 처리할 수 있었다. 공간 기준 샘플링에서 현 및 몸체에서 발생하는 미소 지연 오차에 대해 설명하고 FD (Fractional Delay) 필터를 이용해 미소 지연을 처리하는 방법을 보였다. 그리고 지연에 수에 따른 합성음의 변화를 설명하고 그 결과를 시간 기준 디지털 도파관 모델과 비교하였다.