• Title/Summary/Keyword: Direction measure

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A Comparison of the Trunk Muscle Activity According to the Direction of Upper Extremity Lifting using Elastic Band (탄력밴드를 이용한 팔 들기 시 방향에 따른 몸통근육 활성도 비교)

  • Lee, Hyun-Ok;Bae, Won-Sik;Shin, Jae-Wook
    • Journal of the Korean Society of Physical Medicine
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    • v.11 no.2
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    • pp.25-31
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    • 2016
  • PURPOSE: The purpose of this study was to compare the trunk muscle activity according to the direction of upper extremity lifting using elastic band. METHODS: Thirty three healthy individuals participated in this study. Each subject performed upper extremity lifting using elastic band on two different directions (straight and diagonal). And then we compared the muscle activity of respective trunk muscles of both directions. In order to examine the muscle activity of trunk muscle, we used the electromyogram to measure peak and mean torque in shoulder 90 degree flexion with sitting position. Electromyographic activities were recorded from the external oblique, internal oblique, rectus abdominis, and erector spine muscles during upper extremity lifting. RESULTS: As a result, first, there was significant difference between two directions. The muscle activity of ipsilateral external oblique and contralateral internal oblique is significantly increased in both straight and diagonal directions (p<0.05). Second, the muscle activities of external oblique and internal oblique of both side showed significant difference in diagonal direction (p<0.05). Third, the muscle activity of erector spine of both side showed significant difference in straight direction (p<0.05). CONCLUSION: Through this study, it is important that implement diagonal direction exercise at sitting positions to help increasing muscle activity of ipsilateral external oblique and contralateral internal oblique on patients when activating the trunk muscle or stabilizing the trunk.

A study on improving the low capability of direction finding by interfered phase difference at circular array antennas (원형 배열안테나의 위상간섭에 의한 방향탐지 성능저하 개선 연구)

  • Chung, Jae-Woo;Kim, Young-Kil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.9
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    • pp.2157-2163
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    • 2010
  • This paper includes the study of DOA(Direction of Arrival). CVDF(Correlative Vector Direction Finding) algorithm using at the phase difference each antenna needs to obtain ideal sinusoidal phase difference patterns. However, the phase difference patterns of circular array antennas may be interfered on a specific frequency band and to particular angle. The effect of installing each array antenna circularly and the effect of the interference by center pole (located in the center of a circular array antennas) may distort the phase difference patterns. This paper propose how to change the combination of antennas to measure phase difference patterns in real-time and how to use antenna beam patterns for minimizing the degradation phenomena with old CVDF algorithm. According to the test result, the capability of direction finding is improved.

Design of a Cross-obstacle Neural Network Controller using Running Error Calibration (주행 오차 보정을 통한 장애물 극복 신경망 제어기 설계)

  • Lim, Shin-Teak;Yoo, Sung-Goo;Kim, Tae-Yeong;Kim, Yeong-Chul;Chong, Kil-To
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.5
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    • pp.463-468
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    • 2010
  • An obstacle avoidance method for a mobile robot is proposed in this paper. Our research was focused on the obstacles that can be found indoors since a robot is usually used within a building. It is necessary that the robot maintain the desired direction after successfully avoiding the obstacles to achieve a good autonomous navigation performance for the specified project mission. Sensors such as laser, ultrasound, and PSD (Position Sensitive Detector) can be used to detect and analyze the obstacles. A PSD sensor was used to detect and measure the height and width of the obstacles on the floor. The PSD sensor was carefully calibrated before measuring the obstacles to achieve better accuracy. Data obtained from the repeated experiments were used to plot an error graph which was fitted to a polynomial curve. The polynomial equation was used to navigate the robot. We also obtained a direction-error model of the robot after avoiding the obstacles. The prototypes for the obstacle and direction-error were modeled using a neural network whose inputs are the obstacle height, robot speed, direction of the wheels, and the error in direction. A mobile robot operated by a notebook computer was setup and the proposed algorithm was used to navigate the robot and avoid the obstacles. The results showed that our algorithm performed very well during the experiments.

A Study on the Comparative Analysis of Images and Doses According to Tube Orientation During Anterior-Posterior Axial Projection Examination of the Skull (머리뼈 전-후 축 방향검사 시 Tube 방향설정에 따른 표면선량과 영상분석에 관한 연구)

  • Jeong, Sung-Hun;Yoo, Je-hyeon;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.44 no.4
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    • pp.301-306
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    • 2021
  • The skull has peripheral organs such as the crystalline lens and thyroid gland, which are highly radiosensitive, but the examination is performed without considering the uneven dose distribution due to the heel effect at the time of the current Skull Town's examination. However, no studies have been conducted on the exposure dose of surrounding organ tissues due to the difference in image density due to the heel effect and the non-uniformity of the dose. Using the cathode (-) and anode (+) set on the Tube to measure the scattered radiation along the Tube direction as a guide, change 30° and 37° in the cathode direction and 30° and 37° in the anode direction. It was given and investigated 5 times to obtain scattered radiation. image measurements were SNR, PSNR, RMSE, and MAE. Measurement results Measurement results of surrounding organ doses when the Tube direction was 30° and 37° The dose was low when the direction was cathodic in all organs (p<0.000). Both cathodes were higher in the image measurements(p<0.04). Continuous research may be needed for diagnostically valuable imaging and minimization of patient exposure dose.

A study on the relatively causal strength measures in a viewpoint of interestingness measure (흥미도 측도 관점에서 상대적 인과 강도의 고찰)

  • Park, Hee Chang
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.1
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    • pp.49-56
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    • 2017
  • Among the techniques for analyzing big data, the association rule mining is a technique for searching for relationship between some items using various relevance evaluation criteria. This associative rule scheme is based on the direction of rule creation, and there are positive, negative, and inverse association rules. The purpose of this paper is to investigate the applicability of various types of relatively causal strength measures to the types of association rules from the point of view of interestingness measure. We also clarify the relationship between various types of confidence measures. As a result, if the rate of occurrence of the posterior item is more than 0.5, the first measure ($RCS_{IJ1}$) proposed by Good (1961) is more preferable to the first measure ($RCS_{LR1}$) proposed by Lewis (1986) because the variation of the value is larger than that of $RCS_{LR1}$, and if the ratio is less than 0.5, $RCS_{LR1}$ is more preferable to $RCS_{IJ1}$.

Experimental Studies on Swirling Flow in a Vertical Circular Tube

  • Chang, Tae-Hyun;Lee, Chang-Hoan
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.7
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    • pp.907-913
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    • 2011
  • Swirling flows are related to the spiral motion in the tangential direction in addition to the axial and radial direction using several swirl generators. These type of flows are used in combustion chambers to improve flame stability, heat exchanger to enhance heat transfer coefficients, agricultural spraying machines and some vertical pipes to move slurries or transport of materials. However, only a few studies three dimensional velocity profiles in a vertical pipe have been reported. In this present paper, 3 dimension particle image velocimetry(PIV) technique was employed to measure the velocity profiles in water along a vertical circular pipe with Reynolds number from 6000 to 13,000. A tangential inlet condition was used as the swirl generator to produce the required flow. The velocities were measured with swirling flow in the water along the test section using the PIV technique.

An Automatic Focusing Method Using Establishment of Step Size from Optical Axis Interval (광학축 간격의 스텝크기 설정을 통한 오토포커싱 방법)

  • Kim, Gyung Bum;Moon, Soon Hwan
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.1
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    • pp.7-11
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    • 2015
  • In this paper, an automatic focusing method has been proposed for speedy and reliable measurement and inspection in industry. It is very difficult to determine focusing step size and moving direction in one camera autofocusing. The proposed method can improve speed and accuracy of focusing by using the optical axis interval of two cameras, which is automatically set up as focusing step size. Also, it can determine moving direction from focus value comparisons of two cameras, and then solve ambiguity of one camera focusing. Its performance is verified by experiments. It is expected that it can apply to optical system for measurement and inspection in industry fields.

A Study on the Sensor Calibration of Motion Capture System using PSD Sensor to Improve the Accuracy (PSD 센서를 이용한 모션캡쳐센서의 정밀도 향상을 위한 보정에 관한 연구)

  • Choi, Hun-Il;Jo, Yong-Jun;Ryu, Young-Kee
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.583-585
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    • 2004
  • In this paper we will deal with a calibration method for low cost motion capture system using psd(position sensitive detection) optical sensor. To measure the incident direction of the light from LED emitted marker, the PSD is used the output current ratio on the electrode of PSD is proportional with the incident position of the light focused by lens. In order to defect the direction of the light, the current output is converted into digital voltage value by opamp circuits peak detector and AD converter with the digital value the incident position is measured. Unfortunately, due to the non-linearly problem of the circuit poor position accuracy is shown. To overcome such problems, we compensated the non-linearly by using least-square fitting method. After compensated the non-linearly in the circuit, the system showed more enhanced position accuracy.

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Axial Direction Velocity and Wall shear Stress Distributions of Turbulent Steady Flow in a Curved Duct (곡관덕트에 난류정상유동의 축방향 속도분포와 벽면전단응력분포)

  • 이홍구;손현철;이행남;박길문
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.1
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    • pp.131-138
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    • 2001
  • In this paper, an experimental investigation of characteristics of developing turbulent steady flows in a square-sectional $180^{\circ}$curved duct is presented. The experimental study using air in a square-sectional $180^{\circ}$ curved duct carryed out to measure axials direction velocity and wall shear stress distrbutions by using Laser Dopper Velocimeter(LDV) system with data acquistion and processing the system of FIND6260 softwere at 7 sections from the inlet($\phi=0^{\circ}$) to the outlet($\phi=180^{\circ}$) in $301^{\circ}$ intervals of a curved duct.

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3 Directional Vibration Measurement of Wide Face Width Helical Gears (광치폭 헬리컬 기어의 3 방향 진동 측정)

  • Park, Chan-Il;Cho, Do-Hyun
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.661-666
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    • 2004
  • The purpose of this study is to measure the rotational vibration, radial vibration, and axial vibration for the helical gear with the wide face width relative to the whole depth. For this purpose, the experimental apparatus is designed and manufactured. The gear vibration of each direction is measured by the accelerometers attached at the gear body. As a result, meshing frequency and second harmonic component are greatly contributed to the gear vibration. As the rotational speed is increased, meshing frequency component has the more significant peak than the second harmonic one. However, the doubled torque decreases the vibration magnitude on the contrary and changes order of the vibration magnitude in each direction.

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