• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.11
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• pp.897-903
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• 1991

In this paper we propose a hybrid position/force controller of a robot manipulator using feedback error learning rule and neural networks. The neural network is constructed from inverse dynamics. The weighting value of each neuron is trained by using a feedback force as an error signal. If the neural networks are sufficiently trained well, it does not require the feedback-loop with error signals. The effectiveness of the proposed hybrid position/force controller is demonstrated by computer simulation using PUMA 560 manipulator.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.2
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• pp.158-163
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• 2013

The fusion of the GPS (Global Positioning System) and DR (Dead Reckoning) is widely used for position and latitude estimation of vehicles such as a mobile robot, aerial vehicle and marine vehicle. Among the many types of aerial vehicles, grater focus is given on the quad-rotor and accuracy of the position information is becoming more important. In order to exactly estimate the position information, we propose the fusion method of GPS and Gyroscope sensor using the DEKF (Dual Extended Kalman Filter). The DEKF has an advantage of simultaneously estimating state value and a parameter of dynamical system. It can also be used even if state value is not available. In order to analyze the performance of DEKF, the computer simulation for estimating the position, the velocity and the angle in a circle trajectory of quad-rotor was done. As it can be seen from the simulation results using own proposed DEKF instead of EKF on own fusion method in the navigation of a quad-rotor gave better performance values.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1140-1141
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• 2017

Depth of SWASH(Small Waterplane Area Single Hull) vessel which is an input value of its control system is measured by ultrasonic sensor. Distance to the its center of gravity can be simply calculated through ultrasonic sensor attached to the front of the vessel from the known values. However, it is to be calibrated with respect to its position for the accurate depth because it has geometric relation between the measurement value of ultrasonic sensor and the depth. In this research, depth calibration method of SWASH vessel using its position and ultrasonic sensor is introduced.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.612-627
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• 2020

This is a case study of Korea Airports Corporation(KAC) examining the effects of pre- and post-employment experience factors on individual and organizational priority. This study surveyed 240 employees of KAC and analyzed the results. The influence of pre-employment experience (number of times applying to public sector, reason to choose public sector, and job changing experience) and post-employment experience (years of employment, position, and job types) on personal value (authority, achievement, welfare, vacation, and personal life) and organizational value (responsibility, obligation, performance, compensation, and participation) was studied. The results indicated that organizational value is generally greater than personal value. Preference value (=organizational value/personal value) was greater than one for every group. Education, years of employment, position, reason to choose public sector were confirmed to influence preference value. For pre-employment factors, as an employee chooses to work in the public sector because of better balance of work-personal life, preference value was confirmed to be lower. For post-employment factors, when the years of employment are longer and the position is higher, preference value is significantly higher. The results imply that an organization should establish a fair evaluation and compensation system to help employees display their full capability to produce maximum performance.

• Journal of Power System Engineering
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• v.20 no.3
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• pp.64-73
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• 2016

In this research work, an algorithm development on tracking end-point of aerial work platform with jib profile and bend-linked boom was carried out to find the X, Y and Z direction value using coordinate transformation matrix. This matrix consists of device status value(length and angle) based on camera position axis, which are sent from device controller PLUS+1 by CAN protocol. These values are used to measure the distance and angle from the camera to the end-point. Using these distance and angle value, monitoring system controls FAN/TILT/ZOOM status of camera to get an adequate scene of workplace. This program was written in Java, C# and C for mobile device. These results provide the information to the aerial work device for secure operation.

• Journal of Korean Port Research
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• v.12 no.1
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• pp.119-130
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• 1998

As a satellite positioning system, GPS is designed to provide the information on three dimensional position, velocity, and time all over the world. The purpose of this paper is to obtain what day has the best accuracy and what time has the best accuracy of measuring of forteen-twenty mimutes for effective using of MAGELLAN G.P.S NAV DLX-10 system. The result of measurement maximum deviation value from November, 1997 to March, 1998 that latitude deviation is 3' .75 and longitude deviation is 2' .1 And the result of measurement maximum deviation value during fourteen minutes of April 29, 1998 that latitude deviation is 3' .75 and longitude deviation is 1' .9. The result of measurement maximum deviation value during twenty minutes of May 6, 1998 that latitude deviation is 4' .75 and longitude deviation is 2' .1 and that is provid 3' .25, 4' .1 to May 13, 1998. So, we expect efficient use of horizontal position for navigation.

• Physical Therapy Korea
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• v.17 no.1
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• pp.1-8
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• 2010

The purpose of this study was to compare EMG activity for pectoralis major muscle during shoulder movement with various abduction angle and rotation position in supine position. Fifteen healthy subjects were recruited for this study. All subjects performed shoulder horizontal adduction holding a 2 kg dumbbell in shoulder abduction $40^{\circ}C$, $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$, $160^{\circ}C$ with shoulder neutral, internal rotation (IR), and external rotation (ER). Surface EMG activity was recorded from pectoralis major clavicle part and pectoralis major sternum part for 5 seconds and EMG activity was normalized to the value of maximal voluntary isometric contraction (%MVIC). Dependent variables were examined with 3 (Neutral, IR, ER) ${\times}$ 5 ($40^{\circ}C$, $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$, $160^{\circ}C$) analysis of variance with repeated measures. The EMG activity of pectoralis major muscle was significantly different between shoulder abduction angles and between shoulder rotation positions (p<.05). The highest value of EMG activity of pectoralis major clavicle part among shoulder abduction angles was in $70^{\circ}C$ and, $90^{\circ}C$ in that order. The highest value of EMG activity of pectoralis major sternum part among shoulder abduction angles was in $130^{\circ}C$ and, $90^{\circ}C$ in that order. According to the rotation degree, shoulder ER showed the highest value and IR showed the lowest value in both muscle parts. These results suggest that shoulder abduction $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$ will be effective during manual muscle testing (MMT) and strengthening exercise for pectoralis major muscle. It is also supposed that shoulder ER is the efficient posture for strengthening of pectoralis major muscle.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.2
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• pp.257-266
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• 1998

This study was conducted to examine the changes of the mechanical properties of the position in jean slacks during the wear, previously used for the wearing test, which were subjected to repeated tensile-shearing deformation using a simulated fatigue tester has been investigated and compared, by calculating both mechanical properties and hand value(HV) of these fabrics with KES-F system and the by obtaining the THV through these calculated properties. The results are as follows. 1. The fatigue phenomenon of mechanical properties was the LT, 2H B, 2HBS, MMD, SMD, RC values increased, elasticity values of tensile, bending and shearing properties, such as B, G and compression properties LC, WC were reduced. It was shown, then, that those fabrics lost their elasticity and became flexible and soft with the increase of fatigue. 2. The hand value and THV; except anterior knee from all part of KOSHI, NUMERI, FUKURAMI was decreased. 3. The fatigue phenomenon of hand value was different on the position of clothing; on the position of hip, rate of B, G smaller than other parts and KOSHI was decreased, on the part of anterior thigh was FUKURAMI was increased, on the anterior knee RC, NUMERI, THV was increased, on the posterior knee was 2HB, 2HG, 2HGS showed increasedgreater than any other part and on the hem of back, MMD was increased, but NUMERI was decreased. 4. The changing process of mechanical properties in the simulation testing by the fatigue tester has similar tendency to that of the wearing tester. It is concluded that this testing method is useful to predict the fatigue phenomena of fabrics caused by wearing.

• International Journal of Advanced Culture Technology
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• v.5 no.3
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• pp.67-72
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• 2017

Transform variation technique is constituted the vibration status of the flash-gap recognition level (FGRL) on the distribution recognition function. The recognition level condition by the distribution recognition function system is associated with the scattering vibration system. As to search a position of the dot model, we are consisted of the distribution value with character point by the output signal. The concept of recognition level is composed the reference of flash-gap level for variation signal by the distribution vibration function. For displaying a variation of the FGRL of the maximum-average in terms of the vibration function, and distribution position vibration that was the a distribution value of the far variation of the $Dis-rf-FA-{\alpha}_{MAX-AVG}$ with $5.74{\pm}1.12$ units, that was the a distribution value of the convenient variation of the $Dis-rf-CO-{\alpha}_{MAX-AVG}$ with $1.64{\pm}0.16$ units, that was the a distribution value of the flank variation of the $Dis-rf-FL-{\alpha}_{MAX-AVG}$ with $0.74{\pm}0.24$ units, that was the a distribution value of the vicinage variation of the $Dis-rf-VI-{\alpha}_{MAX-AVG}$ with $0.12{\pm}0.01$ units. The scattering vibration will be to evaluate at the ability of the vibration function with character point by the distribution recognition level on the FGRL that is showed the flash-gap function by the recognition level system. Scattering recognition system will be possible to control of a function by the special signal and to use a distribution data of scattering vibration level.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.6
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• pp.463-472
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• 2017

Inertial Navigation System Alignment is the process to determine direction cosine matrix which is the transformation matrix between the INS body frame and navigation frame. INS initial position value is necessary to INS attitude calculation, so that user should wait until he get such value to start the INS alignment. To remove the waiting time, we propose an alignment algorithm that immediately starts after the INS power on by using pseudo initial position input and then is completed with attitude error compensation by entering true position later. We analyse effect of INS sensor error on attitude in process of time and verify the performance and usefulness of the close-loop alignment algorithm which corrects attitude error from the change of initial position.