• 제목/요약/키워드: Main Axis

검색결과 537건 처리시간 0.029초

진돗개에서 심장초음파 측정치와 평가와 임상적 응용 (Echocardiograpyhic Assessment and Clinical Application of Cardiac Disease in Korea Jin-do Dog III. Detection of Heartworm)

  • 박인철;강병규;손창호
    • 한국임상수의학회지
    • /
    • 제17권1호
    • /
    • pp.194-204
    • /
    • 2000
  • Echocardiography was performed to obtain the optimal planes for diagnosis of canine heartworm disease in 11 dogs. Imaging planes were taken the left ventricular outflow tract long-axis view, 4-chamber long-axis view, chordae tendineae level short-axis view and modified pulmonary arteries level short-axis view in the right parasternal window, and aptical 4-chamber long-axis view in hte left parasternal window. After echocaridography, the pulmonary artery valve pat was ligated with double 1-0 silk under the general anesthesia to prevent heartworm moving from pulmonary artery to right ventricle. The dogs were euthanized and examained for heartworms in heart and great vessels. Many adult heartworms were identified ultrasonographically within main pulmonary artery, bifurcation of pulmonary artery and right pulmonary artery, but not identified within right ventricle and atrium. At necropsy, adult heartworms were mainly found in pulmonary artery in 11 days, and also found in right ventricular outflow tract and right ventricle in 2 of 11 dogs. The modified pulmonary arteries level short-axis view was the best imaging plane for identifiying heartworms because the main pulmonary artery, branches of pulmonary artery and right pulmonary artery could be showed. The aortic root internal dimension (AOID) and right pulmonary atery internal dimension (RPAID) were measured from the modified pulmonary ateries level short-axis view and left ventricular outflow tract long-axis view. The RPAID and RPAID/AOID was higher in heartworm infected dogs than normal Korea Jin-do dogs in modified pulmonary arteries level short-axis view, and the AOID, RPAID and RPIAID/AOID was higher than in left ventricular outflow tract long-axis view, respectively. These results indicate that the pulmonary arteries were the major habitat of adult heartworm in canine heartworm disease and the modified pulmonary arteries level short-axis view was the best imaging planes for identifying heartworms because the main pulmonary arteries could be showed. Therefore the modified pulmonary arteries level short-axis view can be used for diagnosing heartworm disease and for monitoring dilation of pulmonary artery.

  • PDF

Magnetic Saturation Effect on the Rotor Core of Synchronous Reluctance Motor

  • Kim, Ki-Chan
    • Journal of Electrical Engineering and Technology
    • /
    • 제6권5호
    • /
    • pp.634-639
    • /
    • 2011
  • This paper presents a study on the design parameters that consider the magnetic saturation effect in a rotor core of a synchronous reluctance motor. Two important design parameters in a rotor are selected to analyze the saturation effect of a synchronous reluctance motor, particularly in a rotor core. The thickness of the main segment, which is the main path of the d-axis flux, and the end rip, which affects the q-axis flux, are analyzed using the d-axis and q-axis inductances. Moreover, the characteristics of torque and torque ripple when magnetic saturation takes place are analyzed. The saturation effect is verified by comparing the reluctance torque between the experiment and FEM simulation.

반작용 휠을 이용한 인공위성 지상 자세제어 실험 연구 (An experimental study on attitude control of spacecraft using roaction wheel)

  • 한정엽;박영웅;황보한
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
    • /
    • pp.1334-1337
    • /
    • 1997
  • A spacecraft attitude control ground hardware simulator development is discussed in the paper. The simulator is called KT/KARI HILSSAT(Hardware-In-the Loop Simulator Single Axis Testbed), and the main structure consists of a single axis bearing and a satellite main body model on the bearing. The single axis tabel as ans experimental hardware simulator that evaluates performance and applicability of a satellite before evolving and/or confirming a mew or and old control logic used in the KOREASAT is developed. Attitude control of spaceraft by using reaction wheel is performed.

  • PDF

수직축 풍력터빈의 유동해석에 관한 연구 (A Study on Air Flow Analysis in Vertical-axis Wind Turbine)

  • 이기선;박정철
    • 전기학회논문지P
    • /
    • 제66권4호
    • /
    • pp.158-162
    • /
    • 2017
  • This paper did basic study on the vertical-axis wind turbine. Namely, This paper was try to find the optimum conditions by using the ANSYS CFX simulation program through the changes of the main-blade angle and sub-blade angle. Main-blade Shape #4 angle $45^{\circ}$ compared to others Shape angle $0^{\circ}$ was increased by 157.2[%] to 263.2[%] in the power output and was increased by 110[%] to 250[%] in the power coefficient. Also, when the Shape #5 Fin length of main-blade doubles, because the power output was 70.8[%] compared to Shape #1 and 27.5[%] compared to Shape #4, and the power coefficient was 60[%] compared to Shape #1 and 28.6[%] compared to Shape #4, the power output and the power efficiency were rather reduced. The output current of Shape #4 was increased 109.9[%] compared to Shape #1 and increased 250[%] compared to Shape #5, and The output voltage of Shape #4 was increased 22.5[%] compared to Shape #1 and increased 3.7[%] compared to Shape #4.

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

  • 박동찬;이명호
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1989년도 추계학술대회 논문집 학회본부
    • /
    • pp.421-425
    • /
    • 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.

  • PDF

Geometric Modeling and Five-axis Machining of Tire Master Models

  • Lee, Cheol-Soo
    • International Journal of Precision Engineering and Manufacturing
    • /
    • 제9권3호
    • /
    • pp.75-78
    • /
    • 2008
  • Tire molds are manufactured by aluminum casting, direct five-axis machining, and electric discharging machining. Master models made of chemical wood are necessary if aluminum casting is used. They are designed with a three-dimensional computer-aided design system and milled by a five-axis machine. In this paper, a method for generating and machining a tire surface model is proposed and demonstrated. The groove surfaces, which are the main feature of the tire model, are created using a parametric design concept. An automatically programmed tool-like descriptive language is presented to implement the parametric design. Various groove geometries can be created by changing variables. For convenience, groove surfaces and raw cutter location (CL) data are generated in two-dimensional drawing space. The CL data are mapped to the tread surface to obtain five-axis CL data to machine the master model. The proposed method was tested by actual milling using the five-axis control machine. The results demonstrate that the method is useful for manufacturing a tire mold.

마이크로 3축 링 자이로스코프의 동역학 (Dynamics of a Micro Three-Axis Ring Gyroscope)

  • 최상현;김창부
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2002년도 추계학술대회논문집
    • /
    • pp.37-43
    • /
    • 2002
  • In this paper, we analyse and present mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure angular velocities about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the rotation of the gyroscope main body. The equations of motion, the response to angular velocities, and the relationships between the natural modes of vibration are derived and compared with the previous studies for the design of a micro three-axis ring gyroscope.

  • PDF

마이크로 3축 링 자이로스코프의 동역학 (Dynamics of a Micro Three-axis Ring Gyroscope)

  • 최상현;김창부
    • 한국소음진동공학회논문집
    • /
    • 제12권12호
    • /
    • pp.1001-1009
    • /
    • 2002
  • In this paper, we analyse and present mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure angular velocities about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the rotation of the gyroscope main body. The equations of motion, the response to angular velocities, and the relationships between the natural modes of vibration are derived and compared with the previous studies for the design of a micro three-axis ring gyroscope.

연속회전을 통한 능동 합성개구레이더위성 기동시간 단축 연구 (A Study on Active SAR Satellite Maneuver Time Reduction through Sequential Rotation)

  • 손준원;박영웅
    • 한국항공우주학회지
    • /
    • 제43권7호
    • /
    • pp.648-656
    • /
    • 2015
  • 능동 합성개구레이더 위성의 주요기동은 SAR 안테나 방향을 바꾸기 위한 롤축 기동이다. 그리고 도플러 중심주파수 변화를 최소화하기 위하여 요축 기동이 요구된다. 따라서 토크/모멘텀 용량을 대부분 롤축으로 그 다음으로 요축으로 할당하는 것이 합리적이다. 하지만 궤도 조정 때문에 가끔씩 피치축으로 중심으로 큰 각도의 회전이 요구된다. 본 논문에서는 롤축과 요축의 연속회전을 통한 피치축 기동시간 단축 방법에 대해서 살펴본다. 이들 두 축이 피치축에 비해서 기동성능이 좋기 때문에, 피치축을 중심으로 큰 회전이 요구될 때는 기동시간 단축이 가능하다.

두 개의 곡선형 펜들럼 주행 메커니즘을 갖는 구형로봇 (KisBot II : New Spherical Robot with Curved Two-pendulum Driving Mechanism)

  • 윤중철;안성수;이연정
    • 로봇학회논문지
    • /
    • 제6권4호
    • /
    • pp.323-333
    • /
    • 2011
  • Due to the limited pendulum motion range, the conventional one-pendulum driven spherical robot has limited driving capability. Especially it can not drive parallel direction with center horizontal axis to which pendulum is attached from stationary state. To overcome the limited driving capability of one-pendulum driven spherical robot, we introduce a spherical robot, called KisBot II, with a new type of curved two-pendulum driving mechanism. A cross-shape frame of the robot is located horizontally in the center of the robot. The main axis of the frame is connected to the outer shell, and each curved pendulum is connected to the end of the other axis of the frame respectively. The main axis and pendulums can rotate 360 degrees inside the sphere orthogonally without interfering with each other, also the two pendulums can rotate identically or independent of each other. Due to this driving mechanism, KisBot II has various motion generation abilities, including a fast steering, turning capability in place and during travelling, and four directions including forward, backward, left, and right from stationary status. Experiments for several motions verify the driving efficiency of the proposed spherical robot.