• 제목/요약/키워드: reference dimension

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Contrast-Enhanced Magnetic Resonance Angiography for Evaluation of the Steno-occlusive Disease of the Supraaortic Arteries: Comparison with Computed Tomography Angiography and Digital Subtraction Angiography (조영증강 자기공명 혈관조영술을 이용한 대동맥궁 위 혈관의 협착 및 페쇄 질환 평가: 전산화 단층 혈관조영술 및 디지털 감산혈관조영술과의 비교)

  • Jeh, Su-Kyung;Kim, Bum-Soo;Jung, So-Lyung;Ahn, Kook-Jin;Shin, Yong-Sam;Lee, Kwan-Sung;Kim, Young-In;Lee, Kwang-Soo
    • Investigative Magnetic Resonance Imaging
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    • v.13 no.2
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    • pp.152-160
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    • 2009
  • Purpose : To intra-individually compare diagnostic accuracy of high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) with computed tomography angiography (CTA) and digital subtraction angiography (DSA) for the assessment of supraaortic steno-occlusive disease. Materials and Methods : Twenty-eight patients (20 men, 8 women, 53-79 years of age) underwent supraaortic CE-MRA, CTA and DSA. CE-MRA was performed on two 1.5T MR scanners (voxel dimension: $0.66{\times}0.66{\times}1.1$ or $1.2\;mm^3$), and CTA on 64-slice CT scanners (voxel dimension: $0.42{\times}0.42{\times}0.63\;mm^3$). All the three examinations were completed within 40 days (median 19 days; range 1-40 days). Retrospective evaluation and measurement of diameter of 6 extracranial and 9 intracranial arterial segments was done by 2 experienced radiologists. Results: A total of 420 arterial segments were examined by CE-MRA, CTA and DSA. On DSA, 34 stenoocclusive lesions were noted at extracranial (n= 19) and intracranial (n = 15) vessels. For extracranial stenosis greater than 70%, sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) were 94.7%, 98.7%, 90.0% and 99.3% on CE-MRA, and 94.7%, 99.3%, 94.7% and 99.3% on CTA. For intracranial stenosis greater than 50%, sensitivity; specificity, PPV and NPV were 93.3%, 98.3%, 77.8%and 99.6% on CE-MRA, and 86.7%, 97.9%, 72.2% and 99.1 % on CTA, with DSA as the standard of reference. Conclusion : Supraaortic CE-MRA is as reliable as CTA in depicting the arterial stenosis, and is effective in screening of significant stenosis of both extracranial and intracranial arterial stenosis.

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Determination of Flood Reduction Alternatives for responding to climate change in Gyeongan Watershed (기후변화 대응을 위한 경안천 유역의 홍수저감 대안 선정)

  • Han, Daegun;Choi, Changhyun;Kim, Duckhwan;Jung, Jaewon;Kim, Jungwook;Kim, Soo Jun
    • Journal of Wetlands Research
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    • v.18 no.2
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    • pp.154-165
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    • 2016
  • Recently, the frequency of extreme rainfall event has increased due to climate change and impermeable area also has increased due to rapid urbanization. Therefore, we ought to prepare countermeasures for flood reduction to reduce the damage. To consider climate change, the frequency based rainfall was calculated according to the aimed period(reference : 1971~2010, Target period I : 2011~2040, Target period II : 2041~2070, Target period III : 2071~2100) and the flood discharge was also calculated by climate change using HEC-HMS model. Also, the flood elevation was calculated by each alternative through HEC-RAS model, setting 5 sizes of drainage pumps and reservoirs respectively. The flood map was constructed using topographical data and flood elevation, and the economic analysis was conducted for reduction of flood damage using Multi dimension - Flood Damage Analysis, MD-FDA. As a result of the analysis on the flood control effect, a head of drainage pump was reduced by 0.06m up to 0.44m while it was reduced by 0.01m up to 1.86m in the case of a detention pond. The flooded area shrunk by up to 32.64% from 0.3% and inundation depth also dropped. As a result of a comparison of the Benefit/Cost index estimated by the economic analysis, detention pond E in period I and pump D in period II and III were deemed appropriate as an alternative for climate change. The results are expected to be used as good practices when implementing the flood control works considering climate change.

Anthropometry of Nose in Korean Twenties (20대 한국인 코의 계측치)

  • Bae, Tae Hui;Yu, Young Il;Kim, Woo Seob;Kim, Han Koo
    • Archives of Craniofacial Surgery
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    • v.10 no.2
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    • pp.61-66
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    • 2009
  • Purpose: The aim of this study is to establish anatomical dimension of the nose and nostril shape in Korean twenties. Methods: Authors measured anthropometry of nose in Korean youths 1,000 individuals (male 363, female 637) and analyzed stastically them. Results: The mean measurements are as follows. 1. The shape of nostrils was classified into 7 types by the angle between both long axis of nostril (male / female). Type I ($<40^{\circ}$)1.7% / 1.72%, Type II ($41-70^{\circ}$) 26.17% / 29.35%, Type III ($71-100^{\circ}$) 39.94% / 38.77%, Type IV (unclassified) 3.85% / 5.80%, Type V ($101-130^{\circ}$) 20.93% / 17.89%, Type VI ($131-180^{\circ}$) 7.43% / 5.96%, Type VII ($>180^{\circ}$) 0% / 0.47% 2. Lengths (male/female) Width of nasal root: $25.29{\pm}2.25mm/24.72{\pm}2.40mm$ Width of nose: $37.63{\pm}2.46mm/34.77{\pm}2.11mm$ Width of columella: $7.18{\pm}0.92mm/6.92{\pm}0.86mm$ Width of alar: $4.99{\pm}1.00mm/4.74{\pm}0.91mm$ Width of nostril floor: $10.98{\pm}1.40mm/10.13{\pm}1.73mm$ Protrusion of nasal tip: $17.12{\pm}1.95mm/16.88{\pm}1.84mm$ Length of alar: $27.10{\pm}2.21mm/24.66{\pm}2.18mm$ Length of nasal root: $17.37{\pm}2.51mm/16.08{\pm}2.90mm$ Depth of nasal root: $7.83{\pm}1.63mm/6.82{\pm}1.36mm$ Length of columella: $8.13{\pm}1.40mm/7.30{\pm}1.46mm$ Height of nose: $60.50{\pm}8.90mm/59.14{\pm}9.22mm$ Height of nasal bridge: $52.68{\pm}7.49mm/50.57{\pm}7.71mm$ 3. Angles Nasofacial angle: $30.19{\pm}3.43^{\circ}/29.13{\pm}6.31^{\circ}$ Nasofrontal angle: $134.88{\pm}7.25^{\circ}/139.94{\pm}6.33^{\circ}$ Nasolabial angle: $95.08{\pm}8.95^{\circ}/95.80{\pm}8.93^{\circ}$ 4. Nasal index: $72.60{\pm}9.57%/68.21{\pm}7.03%$ Nasal tip protrusion-nasal height index: $45.64{\pm}5.21%/47.09{\pm}5.21%$ Nasal tip protrusion-nasal width index: $32.61{\pm}6.83%/31.63{\pm}6.71%$ Conclusion: These data could be useful reference for anthropometry of nose in Korean twenties.

Analysis of 3D Accuracy According to Determination of Calibration Initial Value in Close-Range Digital Photogrammetry Using VLBI Antenna and Mobile Phone Camera (VLBI 안테나와 모바일폰 카메라를 활용한 근접수치사진측량의 캘리브레이션 초기값 결정에 따른 3차원 정확도 분석)

  • Kim, Hyuk Gi;Yun, Hong Sik;Cho, Jae Myoung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.1
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    • pp.31-43
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    • 2015
  • This study had been aimed to conduct the camera calibration on VLBI antenna in the Space Geodetic Observation Center of Sejong City with a low-cost digital camera, which embedded in a mobile phone to determine the three-dimension position coordinates of the VLBI antenna, based on stereo images. The initial values for the camera calibration have been obtained by utilizing the Direct Linear Transformation algorithm and the commercial digital photogrammetry system, PhotoModeler $Scanner^{(R)}$ ver. 6.0, respectively. The accuracy of camera calibration results was compared with that the camera calibration results, acquired by a bundle adjustment with nonlinear collinearity condition equation. Although two methods showed significant differences in the initial value, the final calibration demonstrated the consistent results whichever methods had been performed for obtaining the initial value. Furthermore, those three-dimensional coordinates of feature points of the VLBI antenna were respectively calculated using the camera calibration by the two methods to be compared with the reference coordinates obtained from a total station. In fact, both methods have resulted out a same standard deviation of $X=0.004{\pm}0.010m$, $Y=0.001{\pm}0.015m$, $Z=0.009{\pm}0.017m$, that of showing a high degree of accuracy in centimeters. From the result, we can conclude that a mobile phone camera opens up the way for a variety of image processing studies, such as 3D reconstruction from images captured.

Ductile Behavior of Ultra High Performance Fiber Reinforced Concrete Segmental Box Girder (초고강도 섬유보강 콘크리트 분절형 박스거더의 연성 거동)

  • Jeong, Min-Seon;Park, Sung-Yong;Han, Sang-Mook
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.3
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    • pp.282-289
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    • 2017
  • The flexural behavior tests of UHPC segmental Box girder which has 160MPa compressive strength and 15.4m length were carried out. The test variables are area of prestressing wires, volume fraction of steel fibers and longitudinal reinforcing bars in upper flange and web. PS tendons which has 32 strands of 15.2mm diameter in lower flange, 24 strands and 14 strands in lower flange were arranged and volume fraction of 2%, 1.5% and 1.0% is used in box girder concrete. UHPFRC box girder which has 32 strands in lower flange showed the over reinforcement and brittle behavior. UHPFRC box girder which has 24 strands showed the similar peak load as 32 strands girder and ductile behavior as large deflection. UHPFRC box girder which has 14 strands showed half of the peak load of 24 strands box girder and ductile behavior. After the application of the formular for the reinforcement index to the behavior of the UHPFRC box girders, reinforcement index does not determine the characteristic of behavior of UHPFRC box girder exactly. So the index should consider the dimension precisely and modify the reference value corresponding to the 0.005 strain of the prestressing strands.

Wavelet based Fuzzy Integral System for 3D Face Recognition (퍼지적분을 이용한 웨이블릿 기반의 3차원 얼굴 인식)

  • Lee, Yeung-Hak;Shim, Jae-Chang
    • Journal of KIISE:Software and Applications
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    • v.35 no.10
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    • pp.616-626
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    • 2008
  • The face shape extracted by the depth values has different appearance as the most important facial feature information and the face images decomposed into frequency subband are signified personal features in detail. In this paper, we develop a method for recognizing the range face images by combining the multiple frequency domains for each depth image and depth fusion using fuzzy integral. For the proposed approach, the first step tries to find the nose tip that has a protrusion shape on the face from the extracted face area. It is used as the reference point to normalize for orientated facial pose and extract multiple areas by the depth threshold values. In the second step, we adopt as features for the authentication problem the wavelet coefficient extracted from some wavelet subband to use feature information. The third step of approach concerns the application of eigenface and Linear Discriminant Analysis (LDA) method to reduce the dimension and classify. In the last step, the aggregation of the individual classifiers using the fuzzy integral is explained for extracted coefficient at each resolution level. In the experimental results, using the depth threshold value 60 (DT60) show the highest recognition rate among the regions, and the depth fusion method achieves 98.6% recognition rate, incase of fuzzy integral.

Photogrammetric Study of Lip in Young Population in Korean (한국 청년층 구순의 사진 계측학적 연구)

  • Kim, Woo Seob;Hong, Jung Soo;Kim, Han Koo;Kim, Seung Hong
    • Archives of Plastic Surgery
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    • v.32 no.2
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    • pp.155-160
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    • 2005
  • The aim of this study is to establish anatomical dimension of the lip in young population in Korean, using specially designed soft ware with photographic image. We measure 13 anatomical dimensions of lips in 2,229 young people. (917 male, 1312 female, Aged from 18-33 years. Average age 19.7). Statistical analysis of these measurements of large population could offer useful information in facial plastic surgery. The mean measurements are as follows 1. Lengths (male/female) Widths of philtrum: $1.11{\pm}0.19cm/1.02{\pm}0.21cm$ Heights of philtrum: $1.6{\pm}0.24cm/1.47{\pm}0.21cm$ Heights of cupid bow: $0.88{\pm}0.16cm/0.83{\pm}0.16cm$ Height of upper vermilion: $0.74{\pm}0.16cm/0.70{\pm}0.15cm$ Height of lower vermilion: $1.08{\pm}0.17cm/1.02{\pm}0.15cm$ Height of upper lip(Rt.): $1.24{\pm}0.2cm/1.23{\pm}0.2cm$ Height of upper lip(Lt.): $1.24{\pm}0.2cm/1.17{\pm}0.19cm$ Half horizontal length of lip: $2.2{\pm}0.26cm/2.11{\pm}0.2cm$ Horizontal length of lip: $4.41{\pm}0.4cm/4.25{\pm}0.36cm$ Height of lower face: $7.1{\pm}0.58cm/6.52{\pm}0.6cm$ 2. Angles Nasolabial angle: $97.77{\pm}11.97^{\circ}/95.5{\pm}11.34^{\circ}$ Mentolabial angle: $133.88{\pm}14.65^{\circ}/129.27{\pm}13.67^{\circ}$ Angle of Cupid's bow: $111.65{\pm}13.99^{\circ}/116.75{\pm}16.2^{\circ}$ Previous reported photogrammetric measurements was difficult to implement to surgical practice. Because these were printed photographies of the same size. Therefore, in this study, we can measure a lot of objects and items more conveniently and correctly by using proportional program on computer after taking a digital photograph. Consequently, proportional measurements with photogrammetry of lip could be useful and corrective substitute for anthropometrical measuring. These data could be useful reference for preoperative consultation, surgical planning and learning anatomical measurement of lips and adjacent structures.

A Study on the Reconstitution of CPTED Theoretical Model - Focused on the Analysis of Sustainable Development - (CPTED 이론 모델의 재구성에 관한 연구 - 지속가능한 발전 분석을 중심으로 -)

  • Liu, He;Hong, Kwan-Seon
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.302-315
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    • 2020
  • The issue concerning how to integrate with the needs of sustainable development according to Crime Prevention Through Environmental Design(CPTED) theory still continues in the development process of the third-generation theory at the present stage. In addition, the issue is under worldwide controversy and discussion. What is more noteworthy is that the viewpoints under debate and discussion have an influence on the mutual effect and relationship between the theoretical model and the principles in the theoretical model, and the influence can never be underestimated. After a mastery of the overall context of theoretical development, it is believed in this study that the identity of CPTED theory development can provide a diverse understanding dimension and a communication method between the environment and environmental users. On the basis of identity the development of CPTED theory, the crime prevention design mode of CPTED needs to connect different dimensions of sustainability, with the design goal of livability as the starting point, the Top-down model to adjust the safety of the environment. By no means can the environmental condition be improved by solely relying on the previous physical design method in virtue of Bottom-up model. Therefore, in this study, the identity of CPTED will be set as the core combined with Top-down crime prevention design model to propose a visual proposal for the reconstitution of the theoretical model, rather than supplementing the application of the contents or principles at a certain stage. Hence, it is expected to provide reference and enlightenment for the sustainable development of CPTED theory.

3D Face Recognition using Wavelet Transform Based on Fuzzy Clustering Algorithm (펴지 군집화 알고리즘 기반의 웨이블릿 변환을 이용한 3차원 얼굴 인식)

  • Lee, Yeung-Hak
    • Journal of Korea Multimedia Society
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    • v.11 no.11
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    • pp.1501-1514
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    • 2008
  • The face shape extracted by the depth values has different appearance as the most important facial information. The face images decomposed into frequency subband are signified personal features in detail. In this paper, we develop a method for recognizing the range face images by multiple frequency domains for each depth image using the modified fuzzy c-mean algorithm. For the proposed approach, the first step tries to find the nose tip that has a protrusion shape on the face from the extracted face area. And the second step takes into consideration of the orientated frontal posture to normalize. Multiple contour line areas which have a different shape for each person are extracted by the depth threshold values from the reference point, nose tip. And then, the frequency component extracted from the wavelet subband can be adopted as feature information for the authentication problems. The third step of approach concerns the application of eigenface to reduce the dimension. And the linear discriminant analysis (LDA) method to improve the classification ability between the similar features is adapted. In the last step, the individual classifiers using the modified fuzzy c-mean method based on the K-NN to initialize the membership degree is explained for extracted coefficient at each resolution level. In the experimental results, using the depth threshold value 60 (DT60) showed the highest recognition rate among the extracted regions, and the proposed classification method achieved 98.3% recognition rate, incase of fuzzy cluster.

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Dimensionality Reduction Methods Analysis of Hyperspectral Imagery for Unsupervised Change Detection of Multi-sensor Images (이종 영상 간의 무감독 변화탐지를 위한 초분광 영상의 차원 축소 방법 분석)

  • PARK, Hong-Lyun;PARK, Wan-Yong;PARK, Hyun-Chun;CHOI, Seok-Keun;CHOI, Jae-Wan;IM, Hon-Ryang
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.4
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    • pp.1-11
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    • 2019
  • With the development of remote sensing sensor technology, it has become possible to acquire satellite images with various spectral information. In particular, since the hyperspectral image is composed of continuous and narrow spectral wavelength, it can be effectively used in various fields such as land cover classification, target detection, and environment monitoring. Change detection techniques using remote sensing data are generally performed through differences of data with same dimensions. Therefore, it has a disadvantage that it is difficult to apply to heterogeneous sensors having different dimensions. In this study, we have developed a change detection method applicable to hyperspectral image and high spat ial resolution satellite image with different dimensions, and confirmed the applicability of the change detection method between heterogeneous images. For the application of the change detection method, the dimension of hyperspectral image was reduced by using correlation analysis and principal component analysis, and the change detection algorithm used CVA. The ROC curve and the AUC were calculated using the reference data for the evaluation of change detection performance. Experimental results show that the change detection performance is higher when using the image generated by adequate dimensionality reduction than the case using the original hyperspectral image.