• Title/Summary/Keyword: Frontal reference

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Design and Implementation of Frontal-View Algorithm for Smartphone Gyroscopes (스마트폰 자이로센서를 이용한 Frontal-View 변환 알고리즘 설계 및 구현)

  • Cho, Dae-Kyun;Park, Seok-Cheon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.6
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    • pp.199-206
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    • 2012
  • Attempt to use as a marker of natural objects directly in the real world, but there is a way to use the accelerometer of the smartphone, to convert the Frontal-View virtual, because it asks only the pitch of the camera, from the side there is a drawback that can not be converted to images. The proposed algorithm, to obtain the rotation matrix of axis 3 pitch, roll, yaw, we set the reference point of the yaw of the target image. Then, to compensate for the rotation matrix to determine Myon'inji any floor, wall, the ceiling of the target image. Finally, to obtain the homography matrix for obtaining the Frontal-View to account for the difference between the gyro sensor coordinate system and image coordinate system, so we can get the Frontal-View from the captured images through the projection transformation was designed. Was tested to convert Frontal-View the picture was taken in an environment smartphone environment surrounding floor, walls and ceiling in order to evaluate the conversion program Frontal-View has been implemented, in this paper, design and The conversion algorithm implementation, it was confirmed that to convert a regular basis Frontal-View footage taken from multiple angles.

Morphology of the Aging Forehead: A Three-Dimensional Computed Tomographic Study

  • Yi, Hyung Suk
    • Archives of Craniofacial Surgery
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    • v.16 no.2
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    • pp.58-62
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    • 2015
  • Background: Age-related changes have been studied for lower and middle facial bones. Although the forehead comprises one-third of the facial area, no studies have investigated age-related changes in the upper part of the face or forehead. The purpose of this study was to use three-dimensional computed tomography (3D CT) to investigate age-related changes in the frontal bone. Methods: A retrospective review was performed for patients who underwent 3D CT scan of facial bones. Patients were divided by gender and age (20 to 40 years, 41 to 60 years, and above 60 years). The frontal bone curvature was evaluated by the length of frontal bone and by two frontal bone angles in relation to the Frankfurt horizon. Results: In both genders, aging was associated with increasing lower slope length. In elderly men (>60 years), the upper slope angle was significantly higher when compared to younger male subjects. Women demonstrated similar age-related changes, but the differences were only statistically significant for the middle and older age groups. Conclusion: This study demonstrates quantifiable age-related changes in the frontal bone. These findings contribute to the understanding of age-related changes of the facial soft tissues. The mean measurements in each age group can be used as a reference when planning forehead reconstruction.

Three-dimensional morphometric analysis of mandibule in coronal plane after bimaxillary rotational surgery

  • Lee, Sung-Tak;Choi, Na-Rae;Song, Jae-Min;Shin, Sang-Hun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.38
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    • pp.49.1-49.9
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    • 2016
  • Background: The aim of this report is to present a new reference for aesthetic mandible surgery using three-dimensional cone-beam computed tomography-based treatment planning for orthognathic surgery which can be implemented in surgical planning and perioperative procedure. Methods: To make an objective standard for evaluating aesthetic mandibular outline, we make an aesthetic scoring criteria with consideration of asymmetry, broad mandibular border line, and prominent mandibular angle. Two maxillofacial surgeons and two orthodontists rated their aesthetical evaluation from 1 to 5. Experimental group consisting of 47 female and 38 male patients who had rotational orthognathic two-jaw surgery from 2010 to 2011 were chosen according to aesthetic scoring done by two maxillofacial surgeons and two orthodontists. A high aesthetic score (${\geq}16$) means the facial contour is symmetric, with no broad and narrow aesthetic mandible frontal profiles. Control A group consisted of ten female and ten male patients who had no orthognathic surgery experience and low aesthetic score (${\geq}10$). Control B group consisted of ten female and ten male patients who had no orthognathic surgery experience and had anaesthetic mandibular frontal profile and a high aesthetic score (${\geq}16$). The three-dimensional image of the patient was taken from dental cone-beam CT (DCT) scanning (experimental group and control A group: 6 months DCT after surgery, control B group: 1st visit DCT). Each DCT was reformatted to reorient the 3D image using 3D analyzing program (OnDemand3D, cybermed Inc, CA, USA). After selection of 12 landmarks and the construction of reoriented horizontal, vertical, and coronal reference lines, 15 measurements were taken in 3D analysis of frontal mandibular morphology. Afterwards, horizontal and vertical linear measurements and angular measurements, linear ratio were obtained. Results: Mean $Go^{\prime}_{Rt}-Me^{\prime}-Go^{\prime}_{Lt}$ angular measurement was $100.74{\pm}2.14$ in female patients and $105.37{\pm}3.62$ in male patients. These showed significant difference with control A group in both genders. Ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}-Me^{\prime}$ length to some linear measurements (ratio of $Me^{\prime}-Cd^{\prime}_{Rt}Cd^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Me^{\prime}-Go^{\prime}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$) showed significant difference with control A group in both genders. Conclusion: This study was intended to find some standard measurement of mandible frontal view in 3D analysis of aesthetic patient. So, these potential measurement value may be helpful for orthognathic treatment planning to have more aesthetic and perspective outcomes.

Proposition for 4 Channel Frontal Lobe Electrode Configuration and Study on EOG Removal from Measured EEG (4채널 전두엽 전극 배치법의 제안과 측정된 뇌파에서의 안전도 제거에 관한 연구)

  • 신수인;조진호;김명남
    • Journal of Korea Multimedia Society
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    • v.6 no.1
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    • pp.167-175
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    • 2003
  • In this paper, a new electrode configuration and EOG removal method are proposed in order to measure EEG effectively on the frontal lobe and remove EOG in the measured raw EEG. The method of measuring EEG is proposed using four electrodes and a ground electrode on the frontal lobe with a reference electrode at the left earlobe. And also, the separation method using ICA is proposed for EOG removal from the measured EEG, Through the experiments of measuring EEG it was demonstrated that a subject can attach the electrodes by himself easily to measure his own EEG without any assistant and the proposed methods were suitable for removing EOG signal from the measured EEG.

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VALIDITY OF POSTERIOR ANTERIOR CEPHALOMETRIC AND 3D-CT FOR ORBITAL CANTING ANALYSIS (안와 경사의 분석을 위한 정모 두부규격방사선사진, 3D-CT의 유용성 평가)

  • Kim, Jin-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.6
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    • pp.546-553
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    • 2008
  • Purpose: The purpose of this study was to estimate validity of posterior anterior cephalometric and 3D-CT for orbital canting analysis. Materials and methods: Three trained observers classified two patients group using standardized frontal photographs of facial asymmetry patients. Group A consisted of patients with facial asymmetry and orbital canting(n=19), and group B consisted of patients with only facial asymmetry(n=43). Orbital canting was measured with line of bilateral inferior orbitale. Orbital canting measurement was done with posterior anterior cephalometric and 3D-CT. Each horizontal reference line was established by bilateral GWSO(cephalometric), FZS(3D-CT). Maxillary canting and mandibular deviation angle were also measured and analyzed with orbital canting. Results: The mean orbital canting was $3.03{\pm}1.00^{\circ}$ in Group A and $1.11{\pm}0.76^{\circ}$ in Group B in frontal photograph. The mean orbital canting was $1.20{\pm}0.74^{\circ}$ in group A and $1.22{\pm}0.65^{\circ}$ in group B by cephalometric analysis(p>0.05). In 3D-CT, orbital canting was almost paralleled with horizontal reference line. The orbital canting, maxillay canting and mandibular deviation between two groups showed no significant differences except madibular deviation in 3D-CT. Conclusion: Common analysis of posterior anterior cephalometric and 3D-CT is not valide method to evaluate orbital canting for facial asymmetry patients with orbital canting.

A Study on Determination of Frontal QRS Electrical Axis by Minnesota Coding Method (MINNESOTA CODE 분류방식에 의한 전면 QRS 전기축 판정에 관한 연구)

  • Park, Dong-Chan;Lee, Myoung-Ho
    • Proceedings of the KIEE Conference
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    • 1989.11a
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    • pp.421-425
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    • 1989
  • This paper present a algorithm for determination of the frontal QRS axis. Determination of electrical QRS axis helps In the differential diagnosis of wide QRS tachycardia and of hemiblock and In the localization of an accessory pathway. At first detecting R-point data and S-point data and two data is sumed and this data is determind such as positive or negative. Reference data is calculated by 9-point derivertives that is less affected by noise. Secondly, using data of lead2 calculate a morphology, this value is threshold for executing determination algorithm. This process is main body of this algorithm. As this algorithm have a six pattern of the axis that coded by minnesota ending method, the axis is determined more precisely than any other algorithm using 3 leads and affirm a relation of a axis and hemiblock and tachycardia.

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A CEPHALOMETRIC STUDY ON CHANGES OF FACIAL MORPHOLOGY IN THE FRONTAL VIEW FOLLOWING MANDIBLE SETBACK SURGERY ( BSSRO ) IN PATIENTS WITH SKELETAL CLASS III DENTOFACIAL DEFORMITIES (골격성 제3급 부정교합환자의 하악지 시상분할 골절단술후 하안면 폭경 및 고경의 변화에 대한 두부계측 방사선학적 연구)

  • Jang, Hyon-Seok;Rim, Jae-Suk;Kwon, Jong-Jin;Lee, Bu-Kyu;Son, Hyoung-Min
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.3
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    • pp.337-342
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    • 2000
  • Purpose : The purpose of this study was to analyze the lower third facial changes in frontal view after mandibular setback surgery. Materials and Methods : In this study, fifteen subjects(6 males and 9 females) with class III dental and skeletal malocclusions who were treated with BSSRO(Bilateral Sagittal Split Ramus Ostetomy) were used. Frontal cephalometric radiographs were taken preoperatively and more than 6 months postoperatively, and hard tissue(H2-Hl) and soft tissue changes (S2-S1) were measured on vertical and horizontal reference lines. In 15 cases, changes which developed more than 6 months after surgery were studied. Results : The results were as follows. 1. In the facial height, hard tissue $decreased(2.46{\pm}2.76mm)$ with statistical significance(P<0.01), and soft tissue also $decreased(1.64{\pm}3.66mm)$. As a result, the facial height generally becomes shorter after sagittal split ramus osteotomy. 2. In the mandibular width, hard tissue $decreased(2.08{\pm}3.59mm)$ with statistical sgnificance(P<0.05), but soft tissue $increased (2.14{\pm}5.73mm)$ without statistically significant difference(P>0.05) postoperatively. 3. In the facial index, hard tissue $decreased(0.23{\pm}2.21%)$, but soft tissue $increased(2.41{\pm}3.46%)$ with statistical significance. Conclusion : One of the main purpose of orthognathic surgery is to achieve facial esthetics and harmony. In order to fullfill this purpose, it is important to carry out a precise presurgical treatment planning by estimating the changes of frontal profile after surgery.

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Measurement of Thoracic Limb Joint Reference Angles in Purebred Shih-Tzu Dogs by Computed Tomography

  • Jeong, Jaemin;Kim, Eunki;Jeong, Youngeun;Jeong, Seong Mok;Lee, Hae Beom;Kwon, Youngsam
    • Journal of Veterinary Clinics
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    • v.37 no.4
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    • pp.169-174
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    • 2020
  • The purpose of this study was to establish normal values for the thoracic limb joint reference angles in Shih Tzu dogs and to describe the standardized CT methodology for measuring the joint reference angle of the humerus. Five pairs of thoracic limbs of Shih Tzu dogs were collected for the CT scans in this study. Three blinded observers measured the joint reference angle of the humerus and radius for each dog by using CT scans in the frontal, sagittal, and axial planes. The means (± SDs) for the average of the right and left humeral joint reference angles were as follows: mMPHA, 83.74 ± 3.95°; mLDHA, 85.04 ± 2.57°; mCaPHA, 46.75 ± 2.20°; mCrDHA, 79.47 ± 1.97°; and HTA, 19.16 ± 2.38°. Means (± SD) for the average of right and left of the radial joint reference angles were as follows: aMPRA, 85.04 ± 1.58°; aLDRA, 87.59 ± 1.37°; aCrPRA, 84.60 ± 1.46°; aCdDRA, 84.27 ± 1.79°; and RTA, 20.91 ± 3.00°. The intraclass correlation coefficients (ICCs) of the joint reference angles for the inter- and intraobserver reliability were good to excellent, except those for the mCrHA and HTA were moderate. Our results suggest that the method of measuring joint reference angles of other long bones by using CT can be applied to thoracic limbs and can extract valid values for one specific breed.

Investigation of Visual Perception Under Zen-Meditation Based On Alpha-Dependent F-VEPs

  • Liao, Hsien-Cheng;Liu, Chuan-Yi;Lo, Pei-Chen
    • Journal of Biomedical Engineering Research
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    • v.27 no.6
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    • pp.384-391
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    • 2006
  • Variation of brain dynamics under Zen meditation has been one of our major research interests for years. One issue encountered is the inaccessibility to the actual meditation level or stage as a reference. In this paper, we propose an alternative strategy for investigating the human brain in response to external flash stimuli during Zen meditation course. To secure a consistent condition of the brain dynamics when applying stimulation, we designed a recording of flash visual evoked potentials (F-VEPs) based on a constant background EEG (electroencephalograph) frontal $\alpha-rhythm$ dominating activities that increase significantly during Zen meditation. Thus the flash-light stimulus was to be applied upon emergence of the frontal $\alpha-rhythm$. The alpha-dependent F-VEPs were then employed to inspect the effect of Zen meditation on brain dynamics. Based on the experimental protocol proposed, considerable differences between experimental and control groups were obtained. Our results showed that amplitudes of P1-N2 and N2-P2 on Cz and Fz increased significantly during meditation, contrary to the F-VEPs of control group at rest. We thus suggest that Zen meditation results in acute response on primary visual cortex and the associated parts.

Does the maxillary anterior ratio in Korean adults follow the Golden Proportion?

  • Jin, Ming-Xu;Hong, Min-Ho;Lee, Kee-Joon;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
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    • v.8 no.2
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    • pp.125-130
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    • 2016
  • PURPOSE. The purpose of this study was to determine the effect of changes in the horizontal plane angle on the mesiodistal width ratios of the maxillary anterior teeth during the acquisition of frontal view photographs, derive these ratios for Korean adults on the basis of the data obtained, and analyze them using the Golden Proportion as a reference. MATERIALS AND METHODS. In experiment I, 30 plaster casts were mounted on an articulator and positioned on the angle-measuring device with a center setting of $0^{\circ}$. The device was rotated to $10^{\circ}$ in $1^{\circ}$ increments in a counterclockwise direction. At each angle, photographs were obtained and analyzed. Experiment II was based on 60 patients who visited the Department of Prosthodontics at Kyungpook National University Dental Hospital from February 2012 to February 2015. The patients were divided into three groups [Male (M), Female (F), Total (M + F)]. Frontal views were obtained for all groups and analyzed. RESULTS. From $1^{\circ}$ to $10^{\circ}$, the relative mesiodistal width ratios for the maxillary anterior teeth showed no significant differences from those at $0^{\circ}$. In all three groups, the relative width ratio of the maxillary central incisor was smaller than that specified in the Golden Proportion; the opposite was true for the canine. CONCLUSION. Our results suggest that the mesiodistal width ratios of the maxillary anterior teeth do not follow the Golden Proportion in Korean adults, and that a change in the horizontal plane angle from $1^{\circ}$ to $10^{\circ}$ during frontal photography does not affect these ratios.