• 제목/요약/키워드: 3-Dimensional D.P.

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Comparison of cone-beam computed tomography cephalometric measurements using a midsagittal projection and conventional two-dimensional cephalometric measurements

  • Jung, Pil-Kyo;Lee, Gung-Chol;Moon, Cheol-Hyun
    • 대한치과교정학회지
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    • 제45권6호
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    • pp.282-288
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    • 2015
  • Objective: This study investigated whether it is possible to use a two-dimensional (2D) standard in three-dimensional (3D) analysis, by comparing the angles and lengths measured from a midsagittal projection in 3D cone-beam computed tomography (CBCT) with those measured by 2D lateral cephalometric radiography (LCR). Methods: Fifty patients who underwent both LCR and CBCT were selected as subjects. CBCT was reoriented in 3 different methods and the measuring-points were projected onto the midsagittal plane. Twelve angle values and 8 length values were measured on both LCR and CBCT and compared. Results: Repeated measures analysis of the variance revealed statistically significant differences in 7 angular and 5 linear measurements among LCR and 3 types of CBCT (p < 0.05). Of these 12 measurements, multiple comparisons showed that 6 measurements (ANB, AB to FH, IMPA, FMA, Co-Gn, Go-Me) were not significantly different in pairwise comparisons. LCR was significantly different from 3 types of CBCT in 3 angular (SN to FH, interincisal angle, FMIA) and 2 linear (S-Go, Co-ANS) measurements. The CBCT method was similar for all measurements, except for 1 linear measurement, i.e., S-N. However, the disparity between the mean values for all parameters was within the range of clinical measurement error. Conclusions: 3D-CBCT analysis, using midsagittal projection, is a useful method in which the 2D-LCR normative values can be used. Although the measurements changed with reorientation, these changes were not clinically significant.

두경부 종물의 3차원 재건 영상에서, 원형 경계선 중첩을 이용한 경계선 추출법의 응용 (The Application of Circular Boundary Overlapping in 3-D Reconstruction of Neck Tumors)

  • 유영삼
    • 대한두경부종양학회지
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    • 제26권2호
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    • pp.204-211
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    • 2010
  • Background and Objectives : Boundary detection and drawing are essential in 3D reconstruction of neck mass. Manual tracing methods are popular for drawing head and neck tumor. To improve manual tracing, circular boundaries overlapping was tried. Materials and Methods : Twenty patients with neck tumors were recruited for study. Representative frames were examined for shapes of outline. They were all single closed curves. Circular boundaries were added to fill the outlines of the tumors. Inserted circles were merged to form single closed curves(Circular boundary overlapping, CBO). After surface rendering, 3 dimensional images with volumes and area data were made. Same procedures were performed with manual tracing from same cases. 3D images were compared with surgical photographs of tumors for shape similarity by 2 doctors. All data were evaluated with Mann-Whitney test(p<0.05). Results : Shapes of boundaries from CBO were similar with boundaries from manual tracing. Tumor outlines could be filled with multiple circular boundaries., While both boundary tracing gave same results in small tumors, the bigger tumors showed different data. Two raters gave the similar high scores for both manual and CBO methods. Conclusion : Circular boundary overlapping is time saver in 3 dimensional reconstruction of CT images.

Cephalometric Angular Measurements of the Mandible Using Three-Dimensional Computed Tomography Scans in Koreans

  • Kim, Yong Hyun;Kang, Seok Joo;Sun, Hook
    • Archives of Plastic Surgery
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    • 제43권1호
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    • pp.32-37
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    • 2016
  • Background We conducted this study to analyze the values of the key cephalometric angular measurements of the mandible using 3-dimensional (3D) computed tomography scans. Methods In the 106 enrolled patients, a 3D cephalometric analysis was performed to measure the angular variables of the mandible. These values were compared between the two sides and between the two sexes. Results The frontal measurements revealed that the mandibular body curve angle was larger on the left (Lt) side (right [Rt], $141.24{\pm}7.54$; Lt, $142.68{\pm}6.94$; P=0.002) and the gonial angle was larger on the right side (Rt, $134.37{\pm}8.44$; Lt, $131.54{\pm}7.14$; P<0.001). The sagittal measurements showed that the gonial angle was larger on the right side (Rt, $134.37{\pm}8.44$; Lt, $131.54{\pm}7.14$; P>0.05). Further, the transverse measurements revealed that the mandibular body curve angle was larger on the right side (Rt, $140.28{\pm}7.05$; Lt, $137.56{\pm}6.23$; P<0.001). Conclusions These results provide an average of the mandibular angular measurements for the Korean population, establishing a standard for determining surgical patient groups and outcome evaluations in the field of mandible contour surgery.

운전중인 고압전동기에서 절연열화 분석 (Analysis of Insulation Aging in Operating High Voltage Motors)

  • 김희동;주영호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.2175-2178
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    • 2005
  • During normal machine operation, partial discharge(PD) measurements were performed with turbine generator analyzer(TGA) in five high voltage motors(rated 6.6kV). These high voltage motors were installed with 80pF capacitive couplers at the terminal box. The PD patterns were displayed two dimensional and three dimensional. TGA summarizes each plot with two quantities such as the normalized quantity number(NQN) and the peak PD magnitude(Qm). Off-line PD measurements were conducted on five motors. These motors were energized to 3.81kV. The PD levels in pC were measured with a conventional digital PD detector. The comparison of positive to negative PD indicates whether the defect elements of PD are within the insulation or on the insulation surface. Internal discharges were generated in phase A, B and C of COP-B and pulv.-B, in phase B of Pulv. C and in phase C of Pulv.-D motor. Discharge at conductor surface was discovered in phase A of Pulv. D motor. Slot discharges occurred in three phases of Pulv. E motor.

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골격성 3급 부정교합 환자의 하악골 후퇴술 시행후 안모변화에 대한 3차원적 연구 (Three-dimensional analysis of soft and hard tissue changes after mandibular setback surgery in skeletal Class III patients)

  • Park, Jae-Woo;Kim, Nam-Kug;Kim, Myung-Jin;Chang, Young-Il
    • 대한치과교정학회지
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    • 제35권4호
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    • pp.320-329
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    • 2005
  • 하악 수술로 치료한 골격성 3급 부정교합 환자의 연조직 변화를 3차원적으로 분석하였다. 수술전과 수술후에 CT를 촬영하고, 연조직과 경조직을 각각의 임계값에 따라 segmentation였다. FH.평면, 정중시상면, PNS를 포함하는 전두면을 기준으로 공통 좌표계를 구성하고, 이 좌표계를 기준으로 술전, 술후 영상을 위치시켰다. 술후의 변화를 측정하기 위해 각각의 모형에 대해 전두면에 평행한 grid를 형성하였다. Grid내의 교점에서 골조직과 연조직 모형에 투사하여 만나는 점의 좌표값을 구하고, 이를 바탕으로 술후의 변화를 측정하였다. 하악골 후퇴술시 안모의 변화는 하악골 부분에서만 발생한 것이 아니라, 구각부에서도 관찰되었다. 하악골 부위의 연조직 변화는 대응되는 골조직 이동량에 따른 상대적인 값으로 계산하였다. 정중시상면에서의 변화율은 $77\~102\%$로 나타났다. (p<0.05). 정중시상면 이외의 부분의 변화양상도 이와 유사하였다. 구각부에서의 변화는 하악골의 이동을 대표할 수 있는 점의 이동량에 대한 상대적인 값으로 계산하였다. 정중시상면에서의 변화는 B점을 기준으로 $14\~29\%$이고, Pog점을 기준으로 $17\~37\%$, grid상 83번째 점을 기준으로 $11\~22\%$로 관찰되었다.(p<0.05)

Reference points suitable for evaluation of the additional arch length required for leveling the curve of Spee

  • Cho, Yong-Hwa;Lim, Sung-Hoon;Gang, Sung-Nam
    • 대한치과교정학회지
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    • 제46권6호
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    • pp.356-363
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    • 2016
  • Objective: The additional arch length required for leveling (AALL) the curve of Spee (COS) can be estimated by subtracting the two-dimensional (2D) arch circumference, which is the projection of the three-dimensional (3D) arch circumference onto the occlusal plane, from the 3D arch circumference, which represents the arch length after leveling the COS. The purpose of this study was to determine whether the cusp tips or proximal maximum convexities are more appropriate reference points for estimating the AALL. Methods: Sixteen model setups of the mandibular arch with COS depths ranging from 0 mm to 4.7 mm were constructed using digital simulation. Arch circumferences in 2D and 3D were measured from the cusp tips and proximal maximum convexities and used to calculate the AALL. The values obtained using the two reference points were compared with the paired t -test. Results: Although the 3D arch circumference should be constant regardless of the COS depth, it decreased by 3.8 mm in cusp tip measurements and by 0.4 mm in proximal maximum convexity measurements as the COS deepened to 4.7 mm. AALL values calculated using the cusp tips as reference points were significantly smaller than those calculated using the proximal maximum convexities (p = 0.002). Conclusions: The AALL is underestimated when the cusp tips are used as measurement reference points; the AALL can be measured more accurately using the proximal maximum convexities.

Evaluation of accuracy of 3D reconstruction images using multi-detector CT and cone-beam CT

  • Kim, Mi-Ja;Huh, Kyung-Hoe;YI, Won-Jin;Heo, Min-Suk;Lee, Sam-Sun;Choi, Soon-Chul
    • Imaging Science in Dentistry
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    • 제42권1호
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    • pp.25-33
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    • 2012
  • Purpose : This study was performed to determine the accuracy of linear measurements on three-dimensional (3D) images using multi-detector computed tomography (MDCT) and cone-beam computed tomography (CBCT). Materials and Methods : MDCT and CBCT were performed using 24 dry skulls. Twenty-one measurements were taken on the dry skulls using digital caliper. Both types of CT data were imported into OnDemand software and identification of landmarks on the 3D surface rendering images and calculation of linear measurements were performed. Reproducibility of the measurements was assessed using repeated measures ANOVA and ICC, and the measurements were statistically compared using a Student t-test. Results : All assessments under the direct measurement and image-based measurements on the 3D CT surface rendering images using MDCT and CBCT showed no statistically difference under the ICC examination. The measurements showed no differences between the direct measurements of dry skull and the image-based measurements on the 3D CT surface rendering images (P>.05). Conclusion : Three-dimensional reconstructed surface rendering images using MDCT and CBCT would be appropriate for 3D measurements.

Protein Separation in Functional Rice Grains Using Two-Dimensional Gel Electrophoresis

  • Chung, Soo Im;Lee, Sang Chul;Kan, Mi Young
    • 한국작물학회지
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    • 제58권4호
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    • pp.388-392
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    • 2013
  • The proteins from functional rice cultivars (Nogwonchalbyeo, Giant embryonic, Arhyangchalbyeo, and Goamibyeo) and general white rice were extracted and separated using two-dimensional (2D) gel electrophoresis. A wide variation in the molecular weight (MW) and pH range of the expressed proteins in rice samples were observed. The green-kerneled rice (Nogwonchalbyeo) exhibited proteins with MW of 9-57 kDa and appeared at a pH range of 4-7. The Giant embryonic contained proteins with MW of 31-63 kDa and a pH range of 5-6. The aromatic glutinous rice (Arhyangchalbyeo) showed proteins with MW of 24-28 and pH of 5.8-6.8. The high-amylose rice (Goamibyeo) exhibited proteins with MW of 3-63 and pH of 5.2-5.6. The identified proteins uniquely found and highly expressed in each cultivar may have a significant role on rice functionality. The results illustrate that the 2D gel electrophoresis is a valuable method in the determination of the protein expression profiles in functional rice grains and may be useful in the identification of specific marker proteins associated with the functional property of rice.

SMALL DATA SCATTERING OF HARTREE TYPE FRACTIONAL SCHRÖDINGER EQUATIONS IN DIMENSION 2 AND 3

  • Cho, Yonggeun;Ozawa, Tohru
    • 대한수학회지
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    • 제55권2호
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    • pp.373-390
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    • 2018
  • In this paper we study the small-data scattering of the d dimensional fractional $Schr{\ddot{o}}dinger$ equations with d = 2, 3, $L{\acute{e}}vy$ index 1 < ${\alpha}$ < 2 and Hartree type nonlinearity $F(u)={\mu}({\mid}x{\mid}^{-{\gamma}}{\ast}{\mid}u{\mid}^2)u$ with max(${\alpha}$, ${\frac{2d}{2d-1}}$) < ${\gamma}{\leq}2$, ${\gamma}$ < d. This equation is scaling-critical in ${\dot{H}}^{s_c}$, $s_c={\frac{{\gamma}-{\alpha}}{2}}$. We show that the solution scatters in $H^{s,1}$ for any s > $s_c$, where $H^{s,1}$ is a space of Sobolev type taking in angular regularity with norm defined by ${\parallel}{\varphi}{\parallel}_{H^{s,1}}={\parallel}{\varphi}{\parallel}_{H^s}+{\parallel}{\nabla}_{{\mathbb{S}}{\varphi}}{\parallel}_{H^s}$. For this purpose we use the recently developed Strichartz estimate which is $L^2$-averaged on the unit sphere ${\mathbb{S}}^{d-1}$ and utilize $U^p-V^p$ space argument.

대두포장(大豆圃場)에서의 Two-dimensional Ordination 분석법(分析法)에 의한 제초제(除草劑) 살초(殺草) Spectrum 분류(分類) (Classification of Herbicidal Spectrum by Two-Dimensional Ordination Analysis in Soybean Field)

  • 강병화;김한수;김태완;용필순;안창우
    • 한국잡초학회지
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    • 제10권3호
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    • pp.192-196
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    • 1990
  • Two-dimensional 분석법(分析法)이 잡초(雜草)와 제초제(除草劑) 군락형(群落型)을 분류(分類), 제초제(除草劑)의 합리적(合理的)인 혼합처리(混合處理) 방법(方法) 모색(摸索) 및 대두포장(大豆圃場)에서 발생(發生)한 잡초군락(雜草群落)에 따른 효과적(效果的)인 제초제(除草劑) 선발(選拔)을 예찰(豫察)하기 위한 방법(方法)으로 이용되었다. 그 결과(結果)는 아래와 같이 요약(要約)되었다. 1. 11종(種)의 제초제(除草劑)를 피(56%) - 명아주(10%)-쇠비름(8%) 잡초군락형(雜草群落型)인 덕소의 대두포장(大豆圃場)에서 처리(處理)한 결과(結果) 11개(個) 군(群)으로 분류(分類)되었고 쇠비름(58%) - 피(29%) - 참비름(5%) - 바랭이(3%) 잡초군락형(雜草群落型)인 연천의 대두포장(大豆圃場)에 처리(處理)한 결과(結果) 9개군(個群)으로 분류(分類)되었다. 2. Clomazone 처리구(處理區)에서는 Quzalofopmethyl, Haloxfop 및 Kusagard 처리구(處理區)에서는 쇠비름, Bentazon 처리구에서는 피의 우점(優占)이 뚜렷하였다. 3. Two-dimensional ordination 분석법(分析法)이 단순히 유하성계수(類似性係數)를 이용하는 것보다 더 효과적(效果的)으로 제초제(除草劑) 살초(殺草) spectrum 증대 및 혼합처리(混合處理) 또는 체계처리(體系處理)를 위한 제초제(除草劑) 선발(選拔)에 이용할 수 있는 자료(資料) 제공(提供)이 더 용이하였다.

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