• Wind and Structures
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• 제5권2_3_4호
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• pp.257-266
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• 2002

In the recent years flow around bridges are investigated using computer modeling. Selvam (1998), Selvam and Bosch (1999), Frandsen and McRobie (1999) used finite element procedures. Larsen and Walther (1997) used discrete vorticity procedure. The aeroelastic instability is a major criterion to be checked for long span bridges. If the wind speed experienced by a bridge is greater than the critical wind speed for flutter, then the bridge fails due to aeroelastic instability. Larsen and Walther (1997) computed the critical velocity for flutter using discrete vortex method similar to wind tunnel procedures. In this work, the critical velocity for flutter will be calculated directly (free oscillation procedure) similar to the approaches reported by Selvam et al. (1998). It is expected that the computational time required to compute the critical velocity using this approach may be much shorter than the traditional approach. The computed critical flutter velocity of 69 m/s is in reasonable comparison with wind tunnel measurement. The no flutter and flutter conditions are illustrated using the bridge response in time.

• Wind and Structures
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• 제5권2_3_4호
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• pp.301-316
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• 2002

An important goal of computational wind engineering is to impact the design process with simulations of flow around buildings and bridges. One challenging aspect of this goal is to solve the Navier-Stokes (NS) equations accurately. For the unsteady computations, an adaptive finite element technique may reduce the computer time and storage. The preliminary application of a p-version as well as an h-version adaptive technique to computational wind engineering has been reported in previous paper. The details on the implementation of p-adaptive technique will be discussed in this paper. In this technique, two posteriori error estimations, which are based on the velocity and vorticity, are first presented. Then, the polynomial order of the interpolation function is increased continuously element by element until the estimated error is less than the accepted. The second through sixth orders of hierarchical functions are used as the interpolation polynomials. Unequal order interpolations are used for velocity and pressure. Using the flow around a circular cylinder with Reynolds number of 1000 the two error estimators are compared. The result show that the estimated error based on the velocity is lower than that based on the vorticity.

• 보존과학회지
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• 제19권
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• pp.67-72
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• 2006

경주 왕경지역에서 출토된 금동풍탁의 성분조성과 납동위원소비를 분석하였다. 유도결합플라즈마분광분석법(ICP)으로 주성분 및 미량성분 10개 원소를 분석한 결과 풍탁의 소지는 Cu와 Sn의 합금으로서 조성비는 92:4 이었다. 그외 8종(Pb, Zn, Fe, Ag, Ni, As, Sb, Co)의 미량성분은 모두 0.2% 이하로서 검출되었다. 이러한 결과는 Cu와 Sn 광석을 고순도로 정련하여 풍탁을 제조하였다는 것을 의미한다. 풍탁의 납동위원소비는 열이온화질량분석기(TIMS)로 측정하였고, 기존의 한국, 중국 및 일본의 납광석의 산지별 데이터베이스를 이용하여 풍탁 제조에 사용한 원료 산지를 추정하였다. 그 결과 납동위원소비에 의한 원료광석의 산지는 일치하지 않고 있어 판단이 어려워 단정적으로 기술할 수 없었다. 향후 연구과제로 남겨 놓고자 한다. 또한 풍탁의 미세조직을 관찰한 결과 일반적인 주조조직에서 볼 수 있는 dendrite조직이 잘 발달되어 있었으며 특별한 열처리 공정은 발견되지 않았다. 풍탁에 대한 이러한 일련의 과학 분석 결과는 향후 시대적, 지역적으로 풍탁의 비교 연구를 위한 기초자료로서 활용될 수 있다.

• 대한기계학회논문집B
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• 제29권1호
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• pp.35-45
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• 2005

TR-E2 configuration designed by Bell Textron was tested in KARI 1-m wind tunnel. To explore aerodynamic characteristics for the given configuration, a $12\%$ scaled model was fabricated and tested. Wind tunnel test for TR-E2 had been performed by changing the incidence angles of wing and deflection angles of control surfaces. Test result showed that the lower wing incidence angle has more favorable lift to drag ratio compared with original design. Longitudinal and directional characteristics of TR-E2 were found to be stable for the pitch and yaw motions. However, the lateral stability of TR-E2 is not stable for certain control surface deflection.

• 대한건축학회논문집:계획계
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• 제36권2호
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• pp.63-70
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• 2020

In the ancient Buddhist temple area, various metal artifacts are still excavated. Therefore, the aim of this study is to approach the characteristics of ancient architecture through ancient metal artifacts. First, metal decoration of ancient architecture appears for the purpose of structure, decoration, arson. Then, as the method of wood structure is developed, the application is separated into structural, functional and decorative purposes. In ancient times, metal decoration has reduced the role of structure, but its decorative role has expanded. Second, various metallic ornaments were used on the roof of ancient architecture. As the wooden technology developed, the metal decoration was gradually omitted while applying the curve to the roof. Third, the metal ornaments used on the roof of ancient architectures include the ridge central decoration, roof top decoration, a nine-ring decoration, gable board Ornamental Metal, corner flower decoration, eaves nail, wind bell. And subsequent research requires a terminology that can link the results of archeology and Buddhist art through excavation as a result of architecture.

• 한국대기환경학회지
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• 제12권4호
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• pp.459-472
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• 1996

An experimental investigation on the wind flow over smooth bell-shaped two-dimensional hills with hill slopes (the ratio of height to half width) of 0.3 and 0.5 is performed in an atmospheric boundary-layer wind tunnel. Two categories of the models are used in the present investigation; six two-dimensional single-hills, and four continuous double-hills. The measurements of the flow field and surface static-pressure distribution are carried out over the Reynolds number (based on the hill height) of 1.9 $\times 10^4, 3.3 \times 10^4, and 5.6 \times 10^4$. The velocity profiles and turbulence characteristics are measured by the pitot-tube and X-type hot-wire anemometer, respectively. The undisturbed boundary-layer profile on the bottom surface of the wind tunnel is reasonably consistent with the power-law profile with $\alpha = 7.0 (1/\alpha$ is the power-law exponent) and shows good spanwise uniformities. The profiles of turbulent intensity are found to be consistent along the centerline of the wind tunnel. The measured non-dimensional speed-up profiles at the hill crest show good agreements with the predictions of Jackson and Hunt's linear theory. The flow separation occurs in the hill slope of 0.5, and the oil-ink dot method is used to find the reattachment points in the leeside of the hill. The measured reattachment points are compared with the numerical predictions. Comparisons of the mean velocity profiles and surface pressure distributions between the numerical predictions and the experimental results show good agreements.

• 한방안이비인후피부과학회지
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• 제11권1호
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• pp.23-39
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• 1998

The clinical data and thermographic imaging were analyzed on the 100 cases of Bell's palsy who were treated in the Kwang-Ju Oriental Medical Hospita! of Wonkwang University from February to October 1997. All the cases were taken Digital Infrared Thermograph Imaging(DITI) before treatment and 30 cases of them were taken follow up imaging again after recovery. And the following results were obtained. 1. Of 100 cases, under teenager occupied $1\%,\;teenager\;8\%,\;2nd\;decade\;14\%,\;3rd\;decade\;11\%,\;4th\;decade\;16\%,\;5th\;decade\;26\%,\;6th\;decade\;16\%,\;7th\;decade\;7\%\;and\;over\;80\;occupied\;1\%$. 2. Male occupied $48\%$ and female occupied $52\%$. 3. $42\%\;of\;male\;and\;23\%$ of female had the affected side at left side. And right facial nerve palsy occured at $29\%\;of\;male\;and\;29\%$ of female. 4. The most common cause of Bell's palsy was cold wind $18\%$, and the next were excessive labor $15\%,\;stress\;12\%,drinking\;2\%\;and\;cold\;food\;1\%$. 5. Thermal pattern were present as hyperthermal pattern in $44\%$ and hypothermal pattern in $22\%$. 6. The DITI showed hyperthermal pattern as close as to the onset day and changes to hypothermal pattern as times passed. 7. The DITI pattern and post-auricular pain, the most common prodomal syndrome, showed no significant relationship. 8. The relationship between the grade of paralysis and thermal patttern of DITI showed no significance. 9. Mean temperature of loci in affected side indicrtted $30.27^{\circ}C\;at\;Yang\;baek,\;30.02^{\circ}C\;at\;Taeyang,\;29.25^{\circ}C\;at\;Geoyo,\;29.62^{\circ}C\;at\;Jichang,\;29.78^{\circ}C\;at\;Hakwan,\;29.61^{\circ}C\;at\;Hyupgeo,\;and\;30.59^{\circ}C$at Yeopoong. 10. Mean temperature of loci in unaffected side showed $30.16^{\circ}C\;at\;Yang\;baek,\;30.02^{\circ}C\;at\;Taeyang,\;29.61^{\circ}C\;at\;Geoyo,\;29.68^{\circ}C\;at\;Jichang,\;29.70^{\circ}C\;at\;Hakwan,\;29.57^{\circ}C\;at\;Hyupgeo,\;and\;29.89^{\circ}C$at Yeopoong. 11. Of 30 cases who were taken follow up imaging again after recovery, the relationship between delta T at loci and symptoms showed no significance. It should be needed further investigation in order to apply them for clinical evaluation.

• 설비공학논문집
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• 제12권11호
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• pp.972-981
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• 2000

Comprehensive work is done for flows by an axial fan by experimental research. The present model fan is used for air handling device for out-door unit of an air conditioner in home appliance. PIV(Particle Image Velocimetry) system and wind tunnel are adopted for measurements of flows and performance evaluation, respectively. Major experimental conditions are the installation depth of a fan into a bellmouth of it. Optimal position of a fan in an inlet guide tube is observed by examination of fan-performance and flows in both upstream and downstream of the fan. Consequently, in the case of the fan inserted in half depth into the inlet tube, the efficiency of fan shows its maximum value and flow patterns is also streamlined.

• Journal of Acupuncture Research
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• 제25권5호
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• pp.205-211
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• 2008

Objectives : This study is designed in order to evaluate oriental medical treatment of facial diplegia with continued facial palsy. Methods : The authors observed patients by Yanagihara's unweighted grading system for operated acupuncture treatment, herbal medicine treatment and physiotherapy. Results & Conclusions : 1. Both facial grade had different scores in Yanagihara's unweighted grading system for 2 cases when the facial palsy occured. 2. Both cases were diagnosed in wind-cold(feng-han) type. 3. The left and right side of face took different amount of time to recover. 4. Facial diplegia was significantly improved.

• 헤리티지:역사와 과학
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• 제52권2호
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• pp.292-307
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• 2019

불교에서는 부처의 위엄, 부처의 세계가 멀리 있는 것이 아님을 보여주는 방편으로 불상과 그 주변을 아름답게 꾸몄다. 여기에 이용된 각종 불구를 장엄구라고 한다. 장엄구는 불상을 꾸미는 장신구, 광배, 보개, 번 등 다양하며, 건물 밖에 걸었던 풍탁 또한 불교 장엄구의 일종이다. 풍탁은 지금까지도 사원에서 널리 쓰이는 불교 장엄구이다. 중국에서는 낙양 영녕사 목탑, 둔황석굴 등으로 미루어 보아 적어도 6세기 무렵에는 이미 풍탁을 사용한 것으로 보인다. 우리나라 불교사원은 삼국시대에 중국에서 불교가 전래한 것과 동시에 지어졌으므로 사원 건물에 매다는 풍탁도 사원 조성과 그 시작이 크게 다르지 않을 것으로 보인다. 현존하는 가장 이른 풍탁은 백제 미륵사지 <금동풍탁>이다. 우리나라 풍탁은 입면에 따라 종형과 제형으로 구분된다. 이는 옆 변의 형태에 따라 세분화할 수 있다. 종형과 제형 풍탁은 시대가 흐르면서 서로에게 영향을 주었는데, 이러한 모습이 고려시대 풍탁에 가장 잘 드러나고 있다. 고려시대 풍탁은 이전의 형식, 구조, 의장 등을 계승하면서도 기술적으로 발전을 도모하고, 자유로우면서도 과하지 않은 의장을 표현하였다. 특히 고려 소종의 입상연판문대(立狀蓮瓣文帶), 왕실의 위엄을 드러내는 불문(?文), 고려 향로 속 삼환문(三環文)과 범자문(梵字文), 석조물의 창호문(窓戶文) 등 동 시기의 불교 미술품과의 교류를 짐작하게 하는 의장은 고려시대 풍탁에서 가장 두드러지는 부분이다. 이처럼 고려 풍탁은 특정한 규격에 얽매이지 않으면서도 그 역할에 충실했던 것으로 보인다. 본 연구는 지금까지 확인된 우리나라 풍탁을 조사한 결과 고려시대에 제작된 것이 가장 비중이 높다는 점에서 시작되었다. 풍탁 연구는 다른 불교 장엄구에 비해 미진한 실정이기에 가장 많은 고려시대 풍탁을 기반으로 이루어져야 한다고 생각한다. 우선 풍탁이 왜 만들어졌는지를 살펴보고 우리나라 풍탁의 형식을 알아보겠다. 이를 토대로 고려시대 풍탁의 시기별 전개와 특징을 고찰하고자 한다.