• 제목/요약/키워드: position sensitivity

검색결과 432건 처리시간 0.026초

시각장애 아동과 정상 아동의 선자세 균형 비교 (The Comparison Between Blind and Normal Children in Standing Position)

  • 김중선;이정순
    • The Journal of Korean Physical Therapy
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    • 제15권1호
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    • pp.119-154
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    • 2003
  • In this paper, the proprioceptive sensitivity was compared by Foot-Hand task method and the effect of the proprioceptive sensitivity and auditory to the standing position between blind and normal children was measured using BPM for 56 children in 7, 8, 9 and 10 years old. There are three measurement methods are used for BPM : Rest, Forward Looking, 'Sound' position. The following conclusions were obtained from the above measurements. 1. In comparison of proprioceptive sensitivity between blind and normal children, there is no significant difference(p > .05). There is no significant difference in comparison of each age group and also there is no difference in each gender group(p > .05). 2. In comparison of standing position measurement between blind and normal children, there is any difference (p > .05) in three measurement(Rest, Forward Looking, 'Sound' position) but there is no significant difference in each gender difference(p > .05). There is any difference between Rest and 'Sound' position of blind children, also there is any difference between Forward Looking and ' Sound ' position, rest and 'Sound' position of normal children(p > .05). 3. There is no significant difference of correlation between proprioceptive sensitivity test and standing position measurement in Pearson correlation coefficient(p > .05).

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인덕턴스형 미소 변위 측정 시스템과 응답 특성의 분석 (An Inductive Micro Position Sensign System and Analysis of its Response Characteristics)

  • 최동준;최인묵;김수현
    • 한국정밀공학회지
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    • 제18권3호
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    • pp.189-194
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    • 2001
  • This paper presents a mew design of an inductive position sensing system with high sensitivity. The designed system consists of the driving coils, position-detecting coils, and closed loop formed magnetic blocks. To obtain high sensitivity we design a symmetric and closed loop type measuring system with small air-gaps. The elements that affect the system characteristics are turn ratio, excitation frequency, air-gap size, capacitance effect, and load resistance. By experimental investigation, the influences of these elements are examined and the system parameters are selected. The sensitivity of the newly designed system is greater than 2800mV/(V mm) and the linearity error is below${\pm}0.01%; in; the; range; of; {\pm}200{\mu}m$.

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경계요소법을 이용한 압축성형다이 가열선의 최적위치 설계 (Optimal Positioning of Heating Lines in a Compression Molding Die Using the Boundary Element Method)

  • 이부윤;조종래
    • 대한기계학회논문집
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    • 제17권6호
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    • pp.1478-1485
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    • 1993
  • 본 연구에서는 압축 성형다이 가열선의 최적위치를 결정하는 문제를 다이의 형상 최적설계 문제로 정식화하고자 한다. 최적화 문제의 목적은 다이 내면의 온도를 지정된 온도로 균일하게 유지하는 것이다. 또한 Lee, Choi와 Kwak의 형상 설계 민감 도 해석을 위한 직접 미분 방법을 응용하여 가열선 위치변화에 관한 민감도 계산을 위한 경계 적분 방정식을 유도하고, 경계요소법으로 온도와 온도의 민감도를 해석하고 자 한다. 수치적 응용의 예로서, 넓은 평판의 성형을 위한 압축 성형다이의 가열선의 최적위치를 결정하는 문제를 다루고, 최적위치에서 가열선의 개수가 온도의 균일성에 미치는 영향을 검토한다.

Sensitivity of a control rod worth estimate to neutron detector position by time-dependent Monte Carlo simulations of the rod drop experiment

  • Jong Min Park;Cheol Ho Pyeon;Hyung Jin Shim
    • Nuclear Engineering and Technology
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    • 제56권3호
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    • pp.916-921
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    • 2024
  • The control rod worth sensitivity to the neutron detector position in the rod drop experiment is studied by the time-dependent Monte Carlo (TDMC) neutron transport calculations for AGN-201K educational reactor and the Kyoto University Critical Assembly. The TDMC simulations of the rod drop experiments are conducted by the Seoul National University Monte Carlo (MC) code, McCARD, yielding time-dependent neutron densities at detector positions. The detector-position-dependent results of the total control rod worth calculated by the extrapolation, the integral counting, and the inverse methods are compared with the numerical reference using the MC eigenvalue calculations and the experimental results. From these comparisons, it is observed that the total control rod worth can be estimated with a considerable difference depending on the detector position through the rod drop experiment. The proposed TDMC simulation of the rod drop experiment can be applied for searching a better detector position or quantifying a bias for the control rod worth measurement.

동적 평형위치에 있는 다물체계의 모드특성에 미치는 공차의 영향 분석을 위한 해석적 방법 (Analytical Method to Analyze the Effect of Tolerance on the Modal Characteristic of Multi-body Systems in Dynamic Equilibrium)

  • 김범석;유홍희
    • 한국소음진동공학회논문집
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    • 제17권7호
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    • pp.579-586
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    • 2007
  • Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. Sensitivity equations for damped natural frequencies and the transfer function are derived at the dynamic equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated.

인공위성 추진제 탱크의 열적 반응 및 민감도 해석 (Thermal Response and Sensitivity Analysis of Satellite Propulsion Tank)

  • 한조영;이균호;유명종
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2004년도 추계 학술대회논문집
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    • pp.131-136
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    • 2004
  • Thermal control of satellite propellant tank is achieved by patch heaters enabled by thermostat's behavior. It is important to attach the thermostat on the appropriate position of the propellant tank. However its position cannot be given with exact numerics because tank is spherical. Actually the position for thermostat is designated in relevant drawing approximately, therby, the engineer practices depending on his own experience and intuition. The sensitivity analysis for the position of thermostat is performed such that the influence on the thermal behavior and control of tank is examined quantatively. When assembling tank module, the reasonable performance on the thermal control is believed with possible human errors if the uncertainty in the position of thermostat is not quite large.

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Shaping of piezoelectric polyvinylidene fluoride polymer film for tip position sensing of a cantilever beam

  • 이영섭
    • 센서학회지
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    • 제14권4호
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    • pp.225-230
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    • 2005
  • This paper describes a novel tip position sensor made of a triangularly shaped piezoelectric PVDF (polyvinylidene fluoride) film for a cantilever beam. Due to the boundary condition of the cantilever beam and the spatial sensitivity function of the sensor, the charge output of the sensor is proportional to the tip position of the beam. Experimental results with the PVDF sensor were compared with those using two commercially available position sensors: an inductive sensor and an accelerometer. The resonance frequencies of the test beam, measured using the PVDF sensor, matched well with those measured with the two commercial sensors and the PVDF sensor also showed good coherence over wide frequency range, whereas the inductive sensor became poor above a certain frequency.

Inductive Micro Displacement Detecting System with High Sensitivity and Low Linearity Error

  • Park, Dong-June;Park, In-Mook;Kim, Soo-Hyun
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권3호
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    • pp.54-60
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    • 2001
  • A newly designed inductive micro displacement detecting system is presented. The proposed inductive system consists of driving coils, position-detecting coils, cores, and closed-loop formed magnetic blocks. The cores and magnetic blocks are made of Mn-Zn ferrite. When AC sine wave is applied to the driving coils, the time derivative flux is generated within the system, and then induced voltages arise in the position-detecting coils according to the core\`s position. Putting the cores to be moved proportionally to the input displacement, the induced voltage is proportional to input displacement. The parameters that affect the system characteristics are turn ratio, air-gap size, excitation frequency, overlap area, load resistance, capacitance effect, and so forth. Based on the experimental results, the system parameters are selected in such a way as to have high sensitivity ad stable responses. The sensitivity of the proposed inductive displacement-detecting system is greater than 2800mV.V-1mm-1 and the linearity error is below $\pm$0.10% in the range of $\pm$200㎛.

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다물체계의 평형위치에서 고유진동수에 대한 공차해석 (Tolerance Analysis for Natural Frequencies of Multi-body Systems in Dynamic Equilibrium State)

  • 엄승만;최동환;유홍희
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.95-100
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    • 2006
  • Tolerance analysis method for natural frequencies of multi-body systems having a equilibrium position is suggested in this paper. To perform the tolerance analysis, the Monte-Carlo Method is conventionally employed. However, the Monte-Carlo Method has some weakness; spending too much time for analysis and having a low accuracy and hard to converge in the numerical unstable area. To resolve these problems, a tolerance analysis method is suggested in this paper. Sensitivity equations of natural frequencies are derived at the equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivity of natural frequencies can be calculated.

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유도형 변위 센서의 민감도 향상을 위한 형상 최적 설계 (Shape Design Optimization of Inductive Position Sensor to Improve Sensitivity)

  • 홍준희;이동주;신우철
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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    • pp.250-254
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    • 2001
  • The resolution of analog sensor is determined by its sensitivity and amplitude of noise. This paper presents modeling of inductive gap sensor base on equivalent magnetic circuit and analysis of sensitivity. We can simulate static characteristic of inductive gap sensor using this model. Computer simulation show that sensor's sensitivity is affected by magnetic flux's leakage and fringing, and that they are affected by shape of sensor probe. Base on this, we designed shape of inductive position sensor probe.

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