• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1270-1276
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• 2003

This paper describes an analytical method for wheel wear prediction. The outputs from vehicle dynamic software are used to calculation the wheel wear. Two calculation examples are shown for a high-speed line and a conventional line. Through the comparison of two cases, we can see the wheel wear characteristics on the conventional line and the high-speed line. The conventional line has many curved tracks that cause severe wheel flange wear. The influences of curve radius on wheel wear are also described considering the operational performance of the high speed trainset. A method of calculation using contact patch work model is presented for determination of the evolution by wear railway wheels.

• Journal of Chest Surgery
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• v.34 no.5
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• pp.386-392
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• 2001

배경: 기관지에 광범위한 협착을 가지고 있는 환자들에게서 협착된 기관지 이하 부위에 있는 폐를 절제하지 않고 기관지 협착 부위를 교정하여 폐환기를 원할하게 하고자 하는 다양한 술식의 기관지 성형술이 고안시도되어 왔지만 만족할만한 술기는 아직 정립되어 있지 않다. 저자들은 이러한 기관지 협착을 교정하기 위한 술식의 하나로서 기관지 대치물을 이용한 기관 성형술의 효과를 조사하기 위하여 본 실험을 시행하였다. 대상 및 방법: 기관지 대치물로 사용한 두 종류의 첨포에 따라 성숙견을 실험 동물로 하여 두 군으로 분류하였으며 A군(5예)에서는 좌측 주기관지 전측방 부위를 0.5$\times$0.5cm 크기의 직사각형으로 절제한 후 늑연골에 자가 심낭편을 댄 동일한 크기의 첨포를 절제 부위에 부착하였고 B군(5예)에서는 동일한 크기의 기관지 절제 부위에 glutaraldehyde로 처리된 우심낭편을 부착하였다. 첨포를 이용한 기관지 성형술 12주후에 실험견을 도살하고 육안적 및 현미경적으로 관찰하였다. 결과: A군이 기관지 성형술 부위에서는 첨포의 외면은 주위의 결합조직과 막상유착을 이루고 있었으며 첨포의 가장자리는 자가 기관지에 잘 부착되어 있었다. 기관지 내면은 내경의 협착이 없이 윤기 있는 점막으로 잘 유지되어 있었고 자가 기관지와 첨호와의 경계면은 신생육아조직이 일부 차지하고 있었으며 새로운 이행 상피가 가교를 이루고 있는 현미경적 소견을 보았다. B군의 기관지 성형술 부위에서는 첨포의 와부는 암갈색으로 변화된 부분적 괴사의 양상을 보였다. 기관지 내면은 첨포와 가자기관지 경계부위에서 염증성 육아조직과 부분적 출현 양상을 보고 기관지 내경의 일부가 수축되었으며 자가 기관지로부터 첨포내로의 새로운 상피 형성은 되어 있지 않았다. 결론: 늑연골에 자가 심낭편을 댄 첨포는는 자가 기관지와 상피 가교를 형성하고 기관지 내강의 협착이 없이 구조를 유지하므로 기관지 협착 및 결손의 치료를 위한 기관지 성형술시에 기관지 대치물로 사용될수 있는 것으로 사료된다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.515-522
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• 2017

In this paper, an isogeometric analysis for multipatch problem is investigated, in which two or more geometries are connected at the interface in a conforming or non-conforming conditions. To express higher continuity at the patch interface, two approaches such as Nitsche based method and master-slave method are formulated for the linear elasticity problem and discretized using the isogeometric approach using NURBS basis functions. A short comparison between two approaches in formulations reveals the pros and cons of them with the applicability in the isogeometric multipatch problem. In addition, a NURBS based stress recovery is adopted to express a better stress continuity through the post-processing. Numerical examples indicate the effectiveness of Nitsche method in the non-conforming patch, following the exact solution well. For the stress concentration problem with the conforming patch, introduced two methodologies show comparative results, meanwhile the NURBS based stress recovery presents an improved smooth stress contour in the whole domain including the patch interface.

• Korean Journal of Remote Sensing
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• v.35 no.6_3
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• pp.1273-1283
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• 2019

This paper proposes an advanced crop classification model that combines a procedure for weighted combination of spatial features extracted from multi-scale input images with a conventional convolutional neural network (CNN) structure. The proposed model first extracts spatial features from patches with different sizes in convolution layers, and then assigns different weights to the extracted spatial features by considering feature-specific importance using squeeze-and-excitation block sets. The novelty of the model lies in its ability to extract spatial features useful for classification and account for their relative importance. A case study of crop classification with multi-temporal Landsat-8 OLI images in Illinois, USA was carried out to evaluate the classification performance of the proposed model. The impact of patch sizes on crop classification was first assessed in a single-patch model to find useful patch sizes. The classification performance of the proposed model was then compared with those of conventional two CNN models including the single-patch model and a multi-patch model without considering feature-specific weights. From the results of comparison experiments, the proposed model could alleviate misclassification patterns by considering the spatial characteristics of different crops in the study area, achieving the best classification accuracy compared to the other models. Based on the case study results, the proposed model, which can account for the relative importance of spatial features, would be effectively applied to classification of objects with different spatial characteristics, as well as crops.

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.321-330
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• 2013

Voice Handicap Index and Voice-Related Quality of Life in Idiopathic Parkinson's Disease 10.7231/jon.2013.24.2.155, The Differences of Learning Characteristics in Sasang Constitution 10.7231/jon.2013.24.2.163, A Preliminary Comparison of the Efficacy of Auricular Acupuncture, Transdermal Nicotine Patch and Combination Therapy for Smoking Cessation 10.7231/jon.2013.24.2.179, The Effects of OnDam-tang-Kami-bang (ODK) in Antioxidant and Serotonin Metabolism Testing on P815 Cell 10.7231/jon.2013.24.2.189

• Journal of Aerospace System Engineering
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• v.7 no.1
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• pp.39-43
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• 2013

In this study, damage assesment and repair technique of aircraft adopted on Sandwich composite structure were performed. The sandwich composite structure were damaged by drop weight type impact test machine. The damaged sandwich composite structure was repaired using external patch repair method after removing damaged area. This study presents comparison results of the experimental investigation between the impact damaged and the repaired specimen.

• Journal of Korean Society of Rural Planning
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• v.21 no.4
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• pp.27-33
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• 2015

Forest ecosystem is considered as an important stepping stone to minimize the impact of climate change. However, the rapid urbanization has caused fragmentation of forest ecosystem. The fragmentation of forest patch results in edge effect which brings about adverse impacts on forest function and structure. Degradation of forest ecosystem decreases carbon sequestration because edge effect reduces productivity. Therefore, we analyzed the impact of forest edge effect on forest ecosystem carbon stock change in Seongnam-si, Gyeonggi-do. We used connectivity analysis to determine forest edge and core area. The field study sites were selected with considering forest age, density, class and soil type. Secondly, forest carbon stock was calculated with allometric equation. The soil carbon stock was derived from Walkely-Black method. Lastly, Mann-Whitney test was conducted to validate differences between carbon stock in edge and core area. As a result of study, the connectivity analysis was effective to determine forest edge and core. The core and edge of forest patch showed different composition of tree species and soil properties. Carbon stock per tree in the edge area was lower than that in the core area. However, the difference of soil organic carbon content between the edge and core were relatively small. This assessment can be applied for the conservation of forest patch as well as quantitative assessment on the forest carbon stock change caused by fragmentation.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.6
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• pp.501-508
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• 2015

Lately, much research on hull plate forming has been successful in improving productivity of the forming process. Those researches include forming methods, forming information, and automation. After forming each plate, the fabricated surface is compared with the corresponding designed surface. Two sets of data from the designed and fabricated surfaces are matched in order to complete the forming process. However, only a few papers deals with comparison of two surfaces. This paper presents a new matching method based on the bounding volume hierarchy (BVH). By comparing the conventional method, this new approach using BVH shows not only good agreement but also better advantages.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.7
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• pp.282-287
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• 2003

″H″ type resonator has the advantage for the miniaturization of high-T7 superconducting (HTS) microstrip antenna in comparison with the conventional microstrip antenna such as rectangular type or circular type. In this paper we designed miniaturized HTS antennas using this "H"-type resonator and reported the characteristics of our antennas including return loss, bandwidth, radiation patterns, efficiency and so on. To fabricate the "H" type antenna, HTS YBa$_2$Cu$_3$$O_{7-x}$ (YBCO) thin films were deposited on MgO substrates using rf-magnetron sputtering. For comparison between normal conducting antennas and superconducting antennas, the gold antennas with the same dimension were also fabricated. An aperture coupling was used for impedance matching between 50 $\Omega$ feed line and HTS radiating patch. The ″H" type superconducting antenna showed the performance of 1.38 in SWR, 26 % in efficiency, and 13.8 dB in the return loss superior to the normal conducting counterpart.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.53-59
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• 2010

There are various types of antenna fed method; coaxial probe, coupling, parasitic elements, and impedance matching. In this paper, the fed method of the proposed antenna is microstrip line type. The high frequency structure simulator (HFSS) is used to analyze the characteristics of the T-shaped microstrip antenna with various patch dimensions. In comparison with the basic microstrip antenna, this proposed T-shaped microstrip antenna with 40.38 % of patch dimensions has the optimum characteristics of resonant frequency, return loss, and radiation pattern at 2.0 GHz band.