• 한국의류학회지
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• 제30권1호
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• pp.157-166
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• 2006

The human body, which is composed of concave and convex curvatures, makes it difficult to transfer into 2D patterns directly from 3D data. In previous studies. Jeong, et al.(2004) suggested the block method was fester and easier when dealing with the triangular patches of male's upper dress form. Although the block method is useful to make a pattern, the information(area, length, etc.) from a 2D pattern would be different depending on the direction of the block method. As a result horizontal and diagonal block methods were suggested as optimal methods for 2D tight-fitting patterns. These block methods were closer to the original area of the 3D scan data than the vertical block method. The total area of the 2D pattern obtained by the horizontal and diagonal block methods showed little differences. In case of the horizontal and diagonal block methods, the total error of the 2D pattern area ranged from $0.01\%\~0.25\%$. In comparing the length of the 2D pattern with that of the 3D scan data, the obtained 2D pattern was $0.1\~0.2cm$ shorter than the 3D scan data, which was within the acceptable range of errors in making clothes. 3D space distribution images between the body surface and the experimental clothing were also measured and $3\%$ enlargement of the original pattern was verified as the adequate adjustment.

• 환경영향평가
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• 제20권4호
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• pp.539-555
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• 2011

Newly constructed, high-rise dense building areas by urban development can cause changes in local wind fields. Wind fields were analyzed to assess the impact on the local meteorology due to the land use changes during the urban redevelopment called "Eunpyeong new town" in north-western Seoul using CFD_NIMR_SNU (Computational Fluid Dynamics, National Institute of Meteorological Research, Seoul National University) model. Initial value of wind speed and direction use analysis value of AWS (Automatic Weather Station) data during 5 years. In the case of the pre-construction with low rise built-up area, it was simulated that the spatial distribution of horizontal wind fields depends on the topography and wind direction of initial inflow. But, in the case of the post-construction with high rise built-up area, it was analyzed that the wind field was affected by high rise buildings as well as terrain. High-rise buildings can generate new circulations among buildings. In addition, small size vortexes were newly generated by terrain and high rise buildings after the construction. As high-rise buildings act as a barrier, we found that the horizontal wind flow was separated and wind speed was reduced behind the buildings. CFD_NIMR_SNU was able to analyze the impact of high-rise buildings during the urban development. With the support of high power computing, it will be more common to utilize sophisticated numerical analysis models such as CFD_NIMR_SNU in evaluating the impact of urban development on wind flow or channel.

• 한국표면공학회지
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• 제42권3호
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• pp.133-138
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• 2009

Effects of bipolar pulse driving frequency between 50 kHz and 250 kHz on the discharge shapes were analyzed by measuring plasma characteristics by OES (Optical Emission Spectroscopy) and Langmuir probe. Plasma characteristics were modeled by a simple electric field analysis and fluid plasma modeling. Discharge shapes by a continuous dc and bipolar pulsed dc were different as a dome-type and a vertical column-type at the cathode. From OES, the intensity of 811.5 nm wavelength, the one of the main peaks of Ar, decreased to about 43% from a continuous dc to 100 kHz. For increasing from 100 kHz to 250 kHz, the intensity of 811.5 nm wavelength also decreased by 46%. The electron density decreased by 74% and the electron temperature increased by 36% at the specific position due to the smaller and denser discharge shape for increasing pulse frequency. Through the numerical analysis, the negative glow shape of a continuous dc were similar to the electric potential distribution by FEM (Finite Element Method). For the bipolar pulsed dc, we found that the electron temperature increased to maximum 10 eV due to the voltage spikes by the fast electron acceleration generated in pre-sheath. This may induce the electrons and ions from plasma to increase the energetic substrate bombardment for the dense thin film growth.

• 한국수산과학회지
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• 제43권5호
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• pp.532-539
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• 2010

Seaweed biomass was estimated in the rocky subtidal zone of Daejin on the mid-east coast of Korea using a destructive sampling method from February to November 2007. Monthly sampling was conducted at depths of 5, 10 and 15 m using 50 $\times$ 50 cm quadrats. A total of 73 species, including 5 chlorophytes, 25 phaeophytes, 43 rhodophytes and one seagrass were identified. Average seaweed biomass was 2,852.3 g wet wt. $m^{-2}$ and biomass values varied monthly from 1,189.8 g to 7,523.7 g. The species dominant in biomass were Laminaria japonica (481.7 g), Sargassum confusum (470.85 g), Undaria pinnatifida (422.57 g), Costaria costata (282.16 g), Odonthalia corymbifera (174.46 g), S. sagamianum (163.22 g) and S. horneri (122.18 g). The vertical distribution of algae was characterized by S. confusum and U. pinnatifida at 5 m, L. japonica and U. pinnatifida at 10 m, and O. corymbifera and L. japonica at 15 m depth. The C/P, R/P and (R+C)/P values were 0.20, 1.72 and 1.92, respectively.

• 대기
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• 제18권2호
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• pp.97-109
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• 2008

The aerosol characteristics in terms of 4 different cases (Asian dust, fog, clear sky and cloud) which had happened at Anmyeon Island in April 2006 were studied using various measurements such as the Micro Pulse Lidar (MPL), sunphotometer, $\beta$-ray $PM_{10}$ Analyzer, anemoscope and anemometer. In addition, synoptic charts, back trajectory analyses and satellite images were also used to help characterize the aerosol events. The aerosol optical properties were featured by the Aerosol Optical Depth (AOD) and ${\AA}ngstr\ddot{o}m$ exponent which were estimated by the sunphotometer. When Anmyeon Island was dominated by the Asian dust, the AOD was sharply increased as seven times as a yearly average of it (0.35). As compared with a yearly average of the ${\AA}ngstr\ddot{o}m$ exponent of 0.97, the ${\AA}ngstr\ddot{o}m$ exponent of a dust day was significantly low (0.099). In addition, $PM_{10}$ mass concentration showed an extremely high record. The maximum concentration reached $1790.5{\mu}gm^{-3}$ on 8 April 2006. The maximum mass concentration was shown with delay when the wind speed of $0ms^{-1}$ was observed. It was also found that a satellite image of the MODIS-RGB had a good agreement with the results of those measurements. It was shown that the MPL was able to describe effectively the vertical distribution of aerosol for all the cases. In particular, the MPL evidently captured the aerosol layer before the cloud observation. The aerosol layer was similarly described by the AOD. On a clear sky day, the AOD had not only a very low value (0.054) but also a feature of homogeneity.

• 대한지리학회지
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• 제37권3호
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• pp.222-236
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• 2002

태백산맥 동사면을 흘러 직접 동해로 유입하는 삼척 오십천의 중.하류부 하안단구는 기후단구와 해면변동단구로 구분된다. 기후단구는 5단이 확인되며, 해면변동단구는 해발고도 145-150m까지 7단의 지형면이 20-30m 간격으로 분포한다. 이와 같은 해면변동단구의 수직적 분포특징은 지반의 지속적인 융기와 기후변화에 의한 빙기와 간빙기의 해면승강작용의 결과이다. 해면변동단구 고고위면은 한반도에서 현재까지 보고된 가장 높은 해안단구보다 해발고도가 더 높다. 해발고도 40m에 분포하는 해면변동단구는 marine oxygen isotope stage 7, 해발고도 70m인 해면변동단구는 stage 9, 해발고도 90m인 해면변동단구는 stage 11, 해발고도 110m 지형면은 stage 13, 해발고도 150m 지형면은 stage 15의 간빙기에 형성된 것으로 추정된다. 중위면, 고위면과 고고위면에는 doline와 함께 uvala와 같은 카르스트지형이 발달하고 있으므로 토지이용과 지형경관이 특징적이다.

• 대한지리학회지
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• 제44권4호
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• pp.429-446
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• 2009

본 연구는 일본 시가현(자하현(滋賀懸)) 기류(동생(桐生))수문시험지의 1차곡 소유역인 마쯔자와 유역에서 유역 내 수문과정과 토양수, 지하수, 계류수의 수질 등의 관측을 실시, 산림유역 내 황(黃) 플럭스를 수문지형학적 관점에서 해석하여 온대 산림유역 내의 황 순환 과정을 밝히고자 실시하였다. 유역 상부 교란 구역의 토양은 ${SO_4}^{2-}$의 공급원으로 작용하고 있었으며, 사면 수문과정을 통해 유역 중부와 하부의 심층토양 및 지하수대에 ${SO_4}^{2-}$가 저장되고 있었다. 계류수의 ${SO_4}^{2-}$ 농도는 지하수위 변동과 음의 상관을 나타내고 있는 바, 이는 심층지하수에 저장된 ${SO_4}^{2-}$가 가뭄 등의 저수위시 혹은 평수위시에 유출되고 있음을 의미한다. 본 연구의 결과로부터 산림유역 내 각 수문과정이 ${SO_4}^{2-}$의 저장과 유출에 중요한 역할을 하고 있다는 것이 정량적으로 밝혀졌다.

• 한국지반공학회지:지반
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• 제8권4호
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• pp.81-98
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• 1992

고층건물이나 지하철등의 건설시 지하굴착을 깊게 실시하므로서 지하공간의 활용도를 증대시킬 수 있다. 이 경우 지하를 연직으로 굴착하기 위하여는 흙막이벽과 지지구조를 안전하게 설계 시공하여야 한다. 최근에는 지하굴착시 지하작업공간확보등의 이점 때문에 흙막이벽지지 구조로 앵가를 만이 사용하는 경향이 있다. 본 논문에서는 사질토지반의 지하굴착을 실시한 8개 감각현장에서 굴착을 위한 흙막이벽을 지지하기 위하여 사용된 앵카에 하중계를 부착하여 앵카의 축력을 측정하였다. 측정된 앵카축력으로부터 환산된 측방토압은 흙락이벽체의 강성에 관계없이 지표면으로 탁터 굴착깊이의 30%에 해당되는 깊이까지는 선형적으로 증가하다가 그 깊이 아래부터는 일정분포를 보이는 사다지꼴모양의 분포를 보였다. 이 일정토압 분포부분의 토압은 평균적으로 최종굴착 깊이에서의 Rankine 주동토압의 63%에 해당하거나 쳔직상개입의 17점에 해당하였다. 이 연구 결과 사질토지반의 앵카지지 흙막이벽의 앵카축력설계에 적용하기 위한 측방토압으로는 Terzaghi-Peck이나 Tschebotarioff의 경험적분포를 다소 수정하여 적용할 수 있음을 알았다.

• 치과방사선
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• 제14권1호
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• pp.135-140
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• 1984

In spite of many projections of TMJ, there are rarely satisfactory projections of TMJ. The author traced and measured the P-A cephalograms, which number is 70 in each male and female, them finding the following results. 1. The long axis of the condyle is 19.80㎜ on the right, and 19.89㎜ on the left in male, and that of 18.65㎜ on the right and 18.10㎜ on the left in female. 2. The intercondylar distance is 119.02㎜ in male, and 108.20㎜ in female, resulting that the intercondylar distance in male is much longer than that in female. 3. The right and left deviation of the midline passing through the center of the intercondylar distance and prosthion is +0.37㎜ in male, +0.64㎜ in female, and its range is from -4.6 to +5.7㎜ in male, and from -3.2 to +6.1㎜ in female, resulting that prosthion nearly coincides with midline. 4. The angle of the intercondylar distance and the long axis (vertical angle) is +5.48' in male, and +6.02' in female, resulting that there is a little difference between male and female and the angle of the right is greater than that of the left in both male and female. 5. The typology of the condyle in sum of male and female is; Right: A type 55 (39.3%), B type 66 (47.1%), C type, 12 (8.6%), D type, 7 (5.0%), E type, 0 (0%) Left: A type, 60 (42.9%), B type, 58 (41.4%), C type, 14 (10.0%), D type, 8 (5.7%), E type, 0 (0%) 6. The distribution of the typology between the right and the left is; AA 26 (18.6%), AB 50 (35.7%), AC 10 (7.1%), AD 3 (2.1%) BB 26 (18.6%), BC 13 (9.3%), BD 9 (6.4%), CC 0 (0%), CD 3 (2.1%)

• 대한치과기공학회지
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• 제40권1호
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• pp.41-47
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• 2018

Purpose: The purpose of this study was to analyze the biomechanical properties of the dental implants on the supporting bone using three-dimensional finite element method when three different abutment materials were applied to the implant system. Methods: Three different dental implant models were fabricated by applying Ti, PEEK, and CRE-PEEK (60% carbon-reinforced PEEK) to abutment material. The abutment and connecting screw from the fixture was applied with a tightening torque of 20 Ncm. And then, total loads of 150 N were applied in an $30^{\circ}oblique$ direction (to the vertical). The structural stability of dental implants on the supporting bone was analyzed using Von Mises stress and principal stress values. Results: The maximum tensile stress of the cortical bone was highest at 12.6 MPa in the PEEK abutment (Model-B). Ti abutment (Model-A) and CRE-PEEK abutment (Model-C) showed similar stress distributions (10.6 and 10.3 MPa, respectively). And the maximum compressive principal stress was similar in all models. The Von Mises stress value delivered to the bone around the implant was highest at 16.5 MPa in Model-B. On the other hand, Model-A and C showed similar stress distributions (14.0 and 13.8 MPa, respectively). In addition, the maximum equivalent stress applied to the abutment was highest at 629.8 MPa in Model-A. The stress distribution in Model-C was 573.9 MPa. Whereas, Model-B showed the lowest value at 165.6 MPa. Conclusion : The dental implant supporting bone system using PEEK material seems to have the possibility of supporting bone fracture. It was found that the CRE-PEEK abutment can reduce the elastic deformation and reduce the stress value of the interfacial bone.