• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.693-697
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• 1989

In this paper, force control for a multi-legged walking robot is investigated. For stable but relatively rapid walking, a simple force control algorithm is proposed in conjunction with the position control system. The proposed control method is tested on an experimental one leg system of two degree of freedom with a force controller using a position controller and a monoboard microcomputer to implement the proposed control algorithm. The experimental results shows that the control algorithm can be applied for walking in a terrain with wide range variation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.376-378
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• 2005

In this study, we have evaluated and classified arthritic pathology using the acoustical analysis of knee joint sounds. Six normal subjects and 11 patients with knee problems were enrolled. Patients were divided into the 1st patient group which required an orthopeadic surgery and the 2nd patient group of osteoarthritis. During sitting and standing periods, subjects' active knee flexion and extension were monitored. Fundamental frequency, mean amplitude of pitch, jitter and shimmer were analyzed according to the position and the joint angle. The result showed that the fundamental frequency of the 2nd patient group and standing position was higher than the others, and that the pitch of sounds changed unstably.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1992년도 추계학술대회 논문집
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• pp.28-33
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• 1992

The paper describes a new mean specific cutting pressure model in order to improve the accuracy of prediction of cutting force for face milling. The new mean specific cutting pressure model produces a mean specific cutting pressure and coefficients applied to existing cutting model not by traditional method but by considering intermittence and variation of chip width according to insert cutting position to take into cutter geometry machining condition and width of workpiece, and considering a mean measure force according to spindle eccentricity and mean measure force according to spindle eccentricity and insert initial position errors.. The simulated forces in X, Y, Z directions resulted from the simulated cutting model and the new cutting model are compared with measured forces in the time end frequency domains. The simulated forces in the time and frequency domains. The simulated forces resulted from the new cutting model have a good degreement with measured forces in comparison with these resulted from the existing cutting model

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1998년도 춘계학술대회 논문집
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• pp.316-322
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• 1998

Super precision working technique and machine tool have been developing continually thanks to advanced electronic field. To obtain good result. it is necessary to investigate surface state in grinding with ${\mu}{\textrm}{m}$ level. There were so many researches to satisfy these demands using non-contact methods through the computer vision. In this study, the texture of working surface was analyzed. cooccurrence matrice was obtained from the surface roughness. Texture parameter was obtained by means of position operator compose of $\theta$. d according to variation of angle direction and distance. As a result, it was found that surface texture was more effected by direction ($\theta$) then distance(d).

• 설비공학논문집
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• 제12권7호
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• pp.680-687
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• 2000

The objective of this study is to improve the control performance of Ondol system which causes overheating and underheating with 2-position on/off control. For this, a predictive control that determines the suitable on/off positions using Artificial Neural Network(ANN) model was proposed Dynamic analyses using computer simulation show that the neural network used in the predictive control is adapted to each room whose loads variation and thermal characteristics are different. To examine the applicability of this predictive control with ANN it was compared with 2-position on/off control through experiments.

• Journal of Forest and Environmental Science
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• 제31권4호
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• pp.267-271
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• 2015

The variations of wood density and mechanical properties of Juniperus polycarpos trees were studied in a natural forest in Iran. Sample disks were taken from each tree to examine wood density and mechanical properties (MOE and MOR) from pith to bark at breast height, 50%, and 75% of total tree height. The analysis of variance (ANOVA) indicated that radial position and height significantly affected all wood properties. The wood density, MOE and MOR were decreased along horizontal position from the pith to the bark and vertical direction from base upwards. Regression analysis showed that modulus of elasticity (MOE) and modulus of rupture (MOR) had a positive correlation with wood density.

• 치과방사선
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• 제6권1호
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• pp.7-14
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• 1976

This study was done using the 45° oblique lateral old, 18 males and 27 females, with normal occlusion, premolars and molars on upper and lower jaws. Axial inclination to nasal floor, occlusal plane and inter-axial inclination were examined. In addition the position of each tooth was examined in height and depth in upper and lower jaws. The results were obtained as follows; 1. The inclination of long axis of upper 1st premolar was most nearly perpendicular, upper canine was tilted mesially, and 2nd premolar and molars were tilted distally. 2. The inclination of long axis of lowers molar were tilted mesially. 3. There were no severe variation on the inter-axial inclination of canine to mandibular plane, and 2nd molar.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.360-363
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• 2009

Variation of viewing position of the observer is one of factors of image distortion in the stereoscopic display. A rotation movement of the observer makes the stereoscopic image distortion and that is caused by different horizontal position of each eye of the observer. It is different from horizontal and depth directional movement of the observer. In this paper, we showed the numerical simulation result about the distortion analysis and the correction of the stereoscopic image in rotation movement of the observer.

• 대한기계학회논문집A
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• 제33권5호
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• pp.508-513
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• 2009

Friction is an important factor for precise position tracking control of servo systems. Servo systems with highly nonlinear friction are sensitive to the variation of operating condition. To overcome this problem, we use the LuGre friction model which can consider dynamic characteristics of friction. The LuGre friction model is used as a feed-forward compensator to improve tracking performance of servo systems. The parameters of the LuGre friction model are identified through experiments. The experimental result shows that the tracking performance of servo systems with higherly nonlinear friction can be improved by using feed-forward friction compensation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.289-292
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• 2002

A sensorless control of a PM synchronous motor under the parameter variation is presented. The rotor position is estimated by using the d-axis and q-axis current errors between the real system and motor model of the estimator. The stator resistance is measured at low speeds when the motor changes its rotating direction. The gains in the position estimator are also adapted according to the motor speeds.