• 제목/요약/키워드: Point-to-point

검색결과 46,461건 처리시간 0.062초

One-point versus two-point fixation in the management of zygoma complex fractures

  • Lee, Kyung Suk;Do, Gi Cheol;Shin, Jae Bong;Kim, Min Hyung;Kim, Jun Sik;Kim, Nam Gyun
    • 대한두개안면성형외과학회지
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    • 제23권4호
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    • pp.171-177
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    • 2022
  • Background: The treatment of zygoma complex fractures is of crucial importance in the field of plastic surgery. However, surgical methods to correct zygoma complex fractures, including the number of fixation sites, differ among operators. Although several studies have compared two-point and three-point fixation, no comparative research has yet been conducted on one-point versus two-point fixation using computed tomography scans of surgical results. Therefore, the present study aimed to address this gap in the literature by comparing surgical results between one-point and two-point fixation procedures. Methods: In this study, we randomly selected patients to undergo surgery using one of two surgical methods. We analyzed patients with unilateral zygoma complex fractures unaccompanied by other fractures according to whether they underwent one-point fixation of the zygomaticomaxillary buttress or two-point fixation of the zygomaticomaxillary buttress and the zygomaticofrontal suture. We then made measurements at three points-the zygomaticofrontal suture, inferior orbital wall, and malar height-using 3-month postoperative computed tomography images and performed statistical analyses to compare the results of the two methods. Results: All three measurements (zygomaticofrontal suture, inferior orbital wall, and malar height) showed significant differences (p< 0.05) between one-point and two-point fixation. Highly significant differences were found for the zygomaticofrontal suture and malar height parameters. The difference in the inferior wall measurements was less meaningful, even though it also reached statistical significance. Conclusion: Using three parameters in a statistical analysis of imaging findings, this study demonstrated significant differences in treatment outcomes according to the number of fixations. The results indicate that bone alignment and continuity can be achieved to a greater extent by two-point fixation instead of one-point fixation.

Development of Classification Technique of Point Cloud Data Using Color Information of UAV Image

  • Song, Yong-Hyun;Um, Dae-Yong
    • 한국측량학회지
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    • 제35권4호
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    • pp.303-312
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    • 2017
  • This paper indirectly created high density point cloud data using unmanned aerial vehicle image. Then, we tried to suggest new concept of classification technique where particular objects from point cloud data can be selectively classified. For this, we established the classification technique that can be used as search factor in classifying color information in point cloud data. Then, using suggested classification technique, we implemented object classification and analyzed classification accuracy by relative comparison with self-created proof resource. As a result, the possibility of point cloud data classification was observable using the image's information. Furthermore, it was possible to classify particular object's point cloud data in high classification accuracy.

Analysis of Average Neutral Point Current in 3-level NPC Converter under Generalized Unbalanced AC Input Condition

  • Jung, Kyungsub;Suh, Yongsug
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2016년도 전력전자학술대회 논문집
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    • pp.151-152
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    • 2016
  • This paper presents a neutral point deviation compensating control algorithm applied to a 3-level NPC converter under generalized unbalanced ac input conditions. The neutral point deviation is analyzed with a focus on the current flowing out of or into the neutral point of the dc-link in 3-level NPC converter. The model of neutral point deviation and neutral current are also constructed. The positive and negative sequence components of the pole voltages and ac input currents are employed to accurately explain the behavior of 3-level NPC converter and its impact on neutral point deviation. This paper includes the harmonic characteristic of neutral point current under various imbalance AC operating conditions.

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무게중심이 변동되는 차륜형 역진자의 평형점 상태에 관한 연구 (A Derivation of the Equilibrium Point for a Controller of a Wheeled Inverted Pendulum with Changing Its Center of Gravity)

  • 이세한
    • 제어로봇시스템학회논문지
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    • 제18권5호
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    • pp.496-501
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    • 2012
  • An equilibrium point of a WIP (Wheeled Inverted Pendulum) with changing its center of gravity is derived and validated by various numerical simulations. Generally, the WIP has two equilibrium points which are unstable and stable one. The unstable one is interested in this study. To keep the WIP over the unstable equilibrium point, the WIP is consistently being adjusted. A state feedback controller for the WIP needs a control reference for the equilibrium point. The control reference can be obtained by studying an equilibrium point of the WIP based on statics. By using Lagrange method, this study is deriving dynamic equations of the WIP both with and without changing its center of gravity. Various numerical simulations are carried out to show the validation of the equilibrium point.

EXISTENCE OF COINCIDENCE POINT UNDER GENERALIZED NONLINEAR CONTRACTION WITH APPLICATIONS

  • Deshpande, Bhavana;Handa, Amrish;Thoker, Shamim Ahmad
    • East Asian mathematical journal
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    • 제32권3호
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    • pp.333-354
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    • 2016
  • We present coincidence point theorem for g-non-decreasing mappings satisfying generalized nonlinear contraction on partially ordered metric spaces. We show how multidimensional results can be seen as simple consequences of our unidimensional coincidence point theorem. We also obtain the coupled coincidence point theorem for generalized compatible pair of mappings $F,G:X^2{\rightarrow}X$ by using obtained coincidence point results. Furthermore, an example and an application to integral equation are also given to show the usability of obtained results. Our results generalize, modify, improve and sharpen several well-known results.

MEASURES FOR STABILITY OF SLOPE ESTIMATION ON THE SECOND ORDER RESPONSE SURFACE AND EQUALLY-STABLE SLOPE ROTATABILITY

  • Park, Sung H.;Kang, Ho-Seog;Kang, Kee-Hoon
    • Journal of the Korean Statistical Society
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    • 제32권4호
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    • pp.337-357
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    • 2003
  • This paper introduces new measures for the stability of slope estimation on the second order response surface at a point and on a sphere. As a measure of point stability of slope estimation, we suggest a point dispersion measure of slope variances over all directions at a point. A spherical dispersion measure is also proposed as a measure of spherical stability of slope estimation on each sphere. Some designs are studied to explore the usefulness of the proposed measures. Using the point dispersion measure, another concept of slope rotatability called equally-stable slope rotatability is proposed as a useful property of response surface designs. We provide a set of conditions for a design to have equally-stable slope rotatability.

The function of point injection in improving learning and memory dysfunction caused by cerebral ischemia

  • Chen, Hua-De
    • 대한약침학회지
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    • 제4권1호
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    • pp.49-53
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    • 2001
  • This experiment has investigated the influence of Yamen (Du. 15) point injection on learning and memory dysfunction caused by cerebral ischemia and reprofusion in bilateral cervical general artery combined with bleeding on mouse tail to mimic vascular dementia in human beings. By dividing 40 mice into 4 groups (group1false operation group, group2model group, group3point injection with Cerebrolysin group4point injection with saline.) According to random dividing principles, we observed the influence of Yamen(Du. 15) point injection on the time of swimming the whole course used by model mice which had received treatment for different days in different groups, and the influence of those mice on wrong times they entered blind end. The result showed that point injection with Cerebrolysin and saline could improve learning and memory dysfunction of the mice caused by cerebral ischemia.

철도 선로전환기 기계식 밀착검지기 개발 (The Development of Mechanical Sensing Device of Railway Point)

  • 유재현;신명호
    • 조명전기설비학회논문지
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    • 제22권1호
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    • pp.50-57
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    • 2008
  • 철도 정거장 구내에서는 본선으로부터 측선으로 진로를 바꾸기 위하여, 즉 다른 선로로 분기하기 위하여 분기지점에 설치한 궤도설비를 분기기라 하며, 분기기의 방향을 전환시키는 장치를 선로전환기라 하는데, 이 장치에 문제가 발생하면 심각한 상황이 초래될 수 있다. 이 장치에는 정밀한 기기와 센서가 설치되어 사용되는데, 장애가 많이 발생하며 열차 탈선이라는 극한의 상황까지 이를 수 있다. 본 논문에서는 사용중인 안전장치들을 장애와 사고를 정밀 분석하고 이를 대체할 수 있는 장치를 개발하였다. 이 장치는 낙뢰에 의한 과전압의 영향을 받지 않도록 설계되어서 열차운행이 원활하게 된다.

최대우도법을 이용한 라이다 포인트군집의 박스특징 추정 (Box Feature Estimation from LiDAR Point Cluster using Maximum Likelihood Method)

  • 김종호;이경수
    • 자동차안전학회지
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    • 제13권4호
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    • pp.123-128
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    • 2021
  • This paper present box feature estimation from LiDAR point cluster using maximum likelihood Method. Previous LiDAR tracking method for autonomous driving shows high accuracy about velocity and heading of point cluster. However, Assuming the average position of a point cluster as the vehicle position has a lower accuracy than ground truth. Therefore, the box feature estimation algorithm to improve position accuracy of autonomous driving perception consists of two procedures. Firstly, proposed algorithm calculates vehicle candidate position based on relative position of point cluster. Secondly, to reflect the features of the point cluster in estimation, the likelihood of the particle scattered around the candidate position is used. The proposed estimation method has been implemented in robot operating system (ROS) environment, and investigated via simulation and actual vehicle test. The test result show that proposed cluster position estimation enhances perception and path planning performance in autonomous driving.

NUMBER OF WEAK GALOIS-WEIERSTRASS POINTS WITH WEIERSTRASS SEMIGROUPS GENERATED BY TWO ELEMENTS

  • Komeda, Jiryo;Takahashi, Takeshi
    • 대한수학회지
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    • 제56권6호
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    • pp.1463-1474
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    • 2019
  • Let C be a nonsingular projective curve of genus ${\geq}2$ over an algebraically closed field of characteristic 0. For a point P in C, the Weierstrass semigroup H(P) is defined as the set of non-negative integers n for which there exists a rational function f on C such that the order of the pole of f at P is equal to n, and f is regular away from P. A point P in C is referred to as a weak Galois-Weierstrass point if P is a Weierstrass point and there exists a Galois morphism ${\varphi}:C{\rightarrow}{\mathbb{p}}^1$ such that P is a total ramification point of ${\varphi}$. In this paper, we investigate the number of weak Galois-Weierstrass points of which the Weierstrass semigroups are generated by two positive integers.