• 건강소식
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• v.38 no.8
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• pp.22-23
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• 2014

르네상스시대의 위대한 천재 레오나르도 다빈치는 인간의 비행을 꿈꿨다. 새와 박쥐, 곤충 등 모든 생명체들의 비행역학을 관찰하고 자신의 모든 지식을 총동원해 날개를 설계했다. 수년간의 실험을 통해 그는 "인간이 새처럼 하늘을 날수 있다는 것은 불가능한 일이다."라는 결론에 도달했다. 그런 그가 지금의 한강변에서 패러세일링을 하는 사람들을 본다면 어떤 기분일까?

• Korean Journal of Health Education and Promotion
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• v.4 no.2
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• pp.1-8
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• 1987

학교는 교육과 연구의 기능을 가친 특수한 사회조직이다. 새로운 과학적인 지식을 습득하게 할 뿐만 아니라 집단생활 속에서 인간관계를 형성하고 상호협력 할 수 있는 경험을 터득하게 하는 장소이다. 그러나 학교는 사회집단으로서 지식제공에 의한 인간개발이나 인간관계에 의한 인격 및 정서발달을 개인 스스로의 체험과 책임으로 돌려 방치하는 자유방임적인 조직은 아니다. (중략)

• 베이커리
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• no.8 s.457
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• pp.64-65
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• 2006

(사)한국생협연대에서 주최한 '제1회 우리밀베이커리경연대회'가 지난 7월 12일 근로복지센터 '위캔'에서 개최됐다. 우리밀의 소비확대와 제빵 기술향상을 목적으로 한 이번 대회는 의무부문 식빵과 자유부문으로 나눠 경연을 펼쳤고 일반 소비자 단체를 심사위원단으로 참여시켜 큰 호응을 이끌었다.

• 주택과사람들
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• s.220
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• pp.39-40
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• 2008

주택 관련 조세 제도를 조세 원칙에 부합되도록 재정비해야 한다는 목소리가 높아지고 있다. 주택 가격 안정 대책 차원에서 단기적으로 다룰 문제가 아니라는 이야기다. 효율성.공평성 등 조세 원칙에 부합되는 합리적인 주택 관련 조세 제도는 무엇인지 해외 사례와의 비교를 통해 알아보자. 자료는 김경환-말페지-김정호의<재산권, 규제, 주택시장(자유기업원, 2008.8.)>을 토대로 했다.

• Defense and Technology
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• no.8 s.162
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• pp.30-34
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• 1992

일본이 1967년 HS-748을 최초로 자체 개발할 당시 1인당 GNP가 1,449불로서 우리나라의 1978년도 경제규모에 해당하며, 자유중국은 1977년 1인당 GNP 657불의 경제력으로 C-2 수송기를 자체 개발하였습니다. 이와 같은 사례에 비추어 경제규모 측면에서만 판단할때, 한국의 독자설계개발이 가능했던 시기는 화폐의 가치하락을 고려하더라도 1980년대 초반으로 볼수 있습니다

• Korean Journal of Biological Psychiatry
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• v.14 no.4
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• pp.232-240
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• 2007

Objectives : Vascular endothelial growth factor(VEGF), one of potent cytokines, and its receptors were related with various biological functions and pathological conditions. The purpose of this study was to investigate the changes of serum level of free VEGF, soluble VEGFR-1, and soluble VEGFR-2 after treatment with atypical antipsychotic drug in schizophrenia. Method : The schizophrenic patients were diagnosed with DSM-IV and were prospectively followed up for 4 and 8 weeks. Thirteen schizophrenic patients were evaluated their clinical assessment with serum levels of free VEGF, sVEGFR-1, sVEGFR-2, and positive and negative symptom scale(PANSS) at baseline, 4 weeks, and 8 weeks after treatment with atypical antipsychotic drug. Thirteen normal control subjects were recruited and matched with the patient group by age and sex. Result : The serum level of free VEGF($295.2{\pm}43.7$pg/ml)and sVEGFR-2($8259{\pm}336.7$) at baseline(before treatment) in schizophrenic patients were not significantly different, compared with the control group($199.0{\pm}28.8$ and $8481{\pm}371.9$) respectively. However, the serum level of sVEGFR-1($86.2{\pm}10.3$, p<0.05) was significantly increased in the schizophrenic patients compared with the control group($59.0{\pm}6.4$). After treatment with antipsychotic drug, the serum levels of free VEGF at 4 weeks($338.9{\pm}56.5$) and 8 weeks($309.5{\pm}58.7$) were not significantly, different compared with baseline. But the serum levels of sVEGFR-1 was significantly decreased at 8 weeks ($57.3{\pm}6.3$, p<0.05) after antipsychotic drug treatment. The serum levels of sVEGFR-2 were decreased at 4 weeks ($7761{\pm}403.0$, p<0.05) and 8 weeks($7435{\pm}333.5$, p<0.05) compared with baseline. Conclusion : The decreased serum level of sVEGFR-1 and sVEGFR-2 might be affected by dopaminergic system which was influenced by antipsychotic drug.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.4
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• pp.109-122
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• 1983

An accurate thick beam element (TB4) which includes the effects of the shear deformation and rotatory inertia has been degenerated from the three dimensional continuum by employing the Timoshenko beam assumptions. The proposed TB4 element has four nodes and two degrees of freedom at each node, totally eight degrees of freedom. The transverse deflection W and plane rotation ${\theta}$ with the cubic interpolation functions are selected as nodal variables. The element characteristics are formulated by discretizing the beam equations of motion, using the Galerkin weighted residual method, and are numerically integrated by the reduced shear integration technique, using the three-point Gauss quadrature with the various shear coefficients. Several numerical examples are analyzed to demonstrate the accuracy and the monotonic convergence behavior of the proposed TB4 beam element. The result indicates that the TB4 element shows the more excellent performance and the monotonic convergence behavior than the other existing Timoshenko beam type elements for the whole range of the beam aspect ratios, in both static and free vibration analyses.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.906-912
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• 2012

This paper presents the new method for a six-degree-of-freedom (DOF) motion measurement and those dynamic characterizations in an ultraprecision linear stage using angle sensor-implemented grating interferometry. It consists of a diffractive optical element, a corner cube, four separate two-dimensional position sensitive detectors, four photodiodes and auxiliary optics components. From the previous study, it was confirmed that the proposed optical system could measure a six-DOF motion error in a linear stage. In this article, six-DOF motion dynamic characteristics of the stage were investigated through the step response and with respect to the conditions with a different speed of a slide table. As a result, the natural frequency and damping ratio according to a six-DOF direction was obtained. Also, it was seen that the speed of slide table had an significant effect on a six-DOF displacement motion, especially, X, which was considered as the effect of friction mechanism and local elastic mechanical deformation in a slide guide.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.12
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• pp.1933-1940
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• 2013

Recently, due to improvement of computer performance and development of information devices, technology of mobile augmented reality is proliferating rapidly. However, because most of contents are passive or limitary, user can not feel interest and immersion. This paper designs interaction user interface system of 2 dimensional drawing based on mobile augmented reality to make bi-directional communication between the real world and the virtual world possible by using the vision based augmented reality and the database system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.8 s.227
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• pp.953-960
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• 2004

In this study, the effects of freestream turbulence intensity on laminar-turbulent transition of separated shear layers in the wake of a circular cylinder are investigated using an immersed boundary method and LES. It is shown that the present numerical results without freestream turbulence for Re=3,900 based on bulk mean velocity and the cylinder diameter are in good agreement with other authors' experimental observations and numerical results, verifying our numerical methodology. Then a 'prescribed power spectrum' method is imposed to generate isotropic turbulence at the inlet of the computational domain at each time step. The principal effects of freestream turbulence intensity on flow statistics are investigated for Re=3,900. Statistical study reveals that the Reynolds stresses in the near-wake region gradually increase, and transition occurs further upstream, as the turbulence intensity increases. On the other hand, the bubble size behind the cylinder decreases as the turbulence intensity increases, which indicates that the freestream turbulence helps mean velocity be quickly recovered.