• The Journal of Korean Physical Therapy
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• v.25 no.2
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• pp.88-95
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• 2013

Purpose: The purpose of this study was to conduct an analysis of kinematics of lower extremities and trunk in stance phase of walking according to turning direction. Methods: Ten university students (five male, five female) who were in their 20s (mean age was 20.6 years old) participated in this study. Participants did not have participants did not have any problem with skeletal muscular system. We used the "Qualisys motion capture system" for analysis of trunk and lower extremity movement in stance phase of walking according to turning direction. We collected data while subjects walked a distance of 10 m, and at the 6 m line, subjects were required to turn to the left side and the right leg was positioned in stance phase and the left leg was positioned in swing. For data analysis, the SPSS for Windows ver. 20.0 statistics program was used in performance of one way analysis of variance according to turning direction. Results: Significant difference of trunk and lower extremities was observed for turning direction according to walking cycle (p<0.05). Upper trunk movement showed a greater increase at three dimensions than lower trunk, and in heel off phase, pelvic movement showed a greater increase than lower trunk (p<0.05). In 45 degree and 90 degrees of turning direction, all movements of trunk and lower extremities were significantly different among three events of stance phase (p<0.05). Conclusion: We suggest that three-dimensional movement analysis of trunk and lower extremities during turning movement was very important in order to indicate increasing balance or walking ability for people with impaired movement or walking.

• Korean Journal of Applied Biomechanics
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• v.14 no.1
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• pp.117-131
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• 2004

The foreign superior players and national team players' turning phase was measured, compared and analyzed to help the representative players improve the skill of turn. The underwater video camera used to analyze and evaluate the representative players' skill of turn in detail and the result is as follows. 1. The record for the phase of turn was similar to the rank of the last record. The improvement of the skill of turn was required because Korean players' record was lower than the foreign players' one. In case of 200m events the 1st turn was the fastest and it took more time as the turn is repeated. 2. It shows that the preparation phase and turing motion cause the difference between the players and within one player. 3. The horizontal movement of center of gravity moves to turning point slowly in the preparation phase, does not move nearly in the turning phase and increase again in the propulsion phase. Good record has short time for turn phase. The result means that the shorten the turning phase is the most important factor. Therefore the preparation for this is required. The vertical movement is maintained or increase a little and then move to from the turning phase. 4. The characteristic of horizontal velocity in center of gravity is that there is any big changes at the preparation phase, the faster velocity is found from the better record and the accelerating time is fast at the propulsion phasen. The wrong motion is made by not using the swimming velocity for fuming and waiting and more time is required by this. 5. The angle of knee when the player touch the turning point is 106.22-135.56 and the maximum angle of knee during the driving after the touch of tuning point is full extension. The size of maximum angle of knee did not match with the required time of propulsion phase. It seems that the individual difference is big when the players touch the turning point the angle of knee and the research for the individual angle which can reveal the maximum power should be carried out. The national team player's skill for the him is behind the foreign players' one and a lot of problems were found. It shows that the players could not practice the skill for turn during the training. The 1st reason for it is the various facilities like underwater window or analyzing equipment like underwater camera with which the coaches can teach and correct the players' detailed skill. It is need to evaluate the players' detailed skill exactly and correct it by objective data to complete the good skill in the future. In this regard, the investment for the facility is necessary.

• 전기의세계
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• v.27 no.6
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• pp.63-68
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• 1978

To convert into multiphase from single phase are often necessary for industry field. In oder to convert of phase, phase shifted voltages are first buileded by single phase and then must combine with these voltages adequately. This paper aims at the description of the way of phase shift by means of turning on or turning off through natural commutation and forced commutation methods with firing angle of thyristor pating a role of switching controlled adequately. Experimental result of the Phase Shift with the Thyristors Utilized has been turned out to shift the phase to 60.deg., 90.deg., 120.deg., and other angles.

• Physical Therapy Korea
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• v.23 no.2
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• pp.11-19
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• 2016

Background: In the stroke patients with the characteristics of hemiplegic gait, turning direction of the affected and unaffected side influences turning time. Therefore, it is important to investigate the walking response to turning directions in stroke patients. Objects: This study aimed to measure the walking time while turning direction in hemiplegic patients depending on balance ability measured by Berg Balance Scale. Methods: A group of forty-five subjects with stroke (Berg Balance Scale score${\geq}46$ were twenty-eight, Berg Balance Scale score${\leq}45$ were seventeen) were enrolled in this study. Subjects were asked to perform the Timed Up and Go test. Testing indications included two directions for turning in each subject. These indications were for turning toward the affected and unaffected side in stroke patients. The duration of total analysis duration, sit to stand phase, stand to sit phase, mid-turning phase, and end turning phase were recorded. The obtained data were analyzed by using paired t-test and Wilcoxon signed rank test in the group that are below and above 45 points of Berg Balance Scale score. The significance level was set at ${\alpha}=.05$. Results: There were significant increase time in the analysis duration and end turning phase duration while subjects were turned the unaffected side in stroke patients that presented a Berg Balance Scale score${\leq}45$ (p<.05). However, the comparison between the affected side and the unaffected side in the stroke patients with Berg Balance Scale score${\geq}46$, revealed no significant differences of the measured parameters. Conclusion: This finding should be suggested in the specific definition of turning direction for evaluation with Timed Up and Go test in the Berg Balance Scale score${\leq}45$, and other intervention for hemiplegic patients need to be suggested the direction of turning during walking training program.

• Journal of the Korean Institute of Navigation
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• v.3 no.1
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• pp.1-17
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• 1979

It is very important for both naval architects and ship's officers to know the maneuvering characteristics of their ships. As the abilities of a rudder which controlls a ship can be determined clearly by analyzing the results of Kempf's zig-zag maneuver and directional stability of a ship also known by Dieudonn spiral maneuver, the importance of turning test which takes much time is recently apt to be neglected. But because the test can be executed comparatively more simply than any other maneuvering tests, it gives some informations on the directional stability, and turning characteristics may be expressed simply by the results of the test, it is still often performed. In this paper several assumptions are made to simplify the turning motion of a ship. The equations of initial transient phase, the radius ofsteady turning circle, and the center of the steady turning point are derived by using the hydrodynamic derivatives. And then the approximate method of drawing the turning circle geometrically is suggested.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1717-1722
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• 2005

The analytical transfer matrix method suggests a new quantization condition for calculating bound state eigenenergies exactly. In the quantization condition, the phase shifts of bound state wave functions scattered at classical turning points are explicitly introduced. We calculate the phase shifts of eigenfunctions of the Morse potential with various boundary conditions in order to understand the physical meaning of phase shifts. The Morse potential is known to adequately describe the interaction energy between two atoms and, therefore, it is frequently used to determine the vibrational energy levels of diatomic molecules. The variation of Morse potential eigenenergies influenced upon by changing boundary conditions is also investigated.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.12
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• pp.841-847
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• 2019

Time series data of 6-component loads were computed for a horizontal axis wind turbine rotor in yawed operating conditions with both rotating and non-rotating coordinate systems fixed at a center of a rotor hub. In this study, a well-known 20 kW class of the NREL Phase VI rotor was used for a model wind turbine, and this paper focuses on the yaw moments and over-turning moments for the operating wind speed range between 6 to 25 m/s. Unsteady blade element momentum theorem was adopted to get the aerodynamic loads acting on the wind turbine rotor. Computed 6-component loads using the developed UBEM code were compared with those using the NREL FAST program. From the computed results, both yaw and over-turning moments would be basic inputs to determine not only the specification of yawing mechanism but also the design condition of foundation.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.285-293
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• 2012

The aim of this study is to identify the appropriate movement for maintaining postural balance during Front Kick and Turning Side Kick motions. To do so, ten Taekwondo athletes: five skilled players(S, body mass: $65.0{\pm}5.8kg$, height: $172.3{\pm}3.7cm$, age: $20.0{\pm}1.2yrs$, career: $9.0{\pm}1.9yrs$) and five less-skilled players(LS, body mass: $67.1{\pm}5.5kg$, height: $173.2{\pm}5.1cm$, age: $19.4{\pm}1.7yrs$, career: $9.6{\pm}1.7yrs$) participated in this study. A three-dimensional motion analysis was performed on the participants using eight infrared cameras and two force plate(sampling frequency of 200 Hz and 2000 Hz for S and LS players, respectively). The participants' motions were divided into: a front-kick phase(P1) and a turning-side-kick phase(P2). For P2(p<.05), the range and root mean square(RMS) of the ground reaction torque and the M-L mean velocity of COP were greater for LS than for S; similarly, for P2(p<.05), the M-L range, A-P range, and velocity of the COP were greater for LS than for S. Further, the M-L range and maximum velocity of the COP was greater for failure than for success(p<.05). The femoral biceps muscle for bending the knee joint was significantly stronger in S than in LS(p<.05). It is expected that these results will be useful in developing a training program for improving the balance and stability of Taekwondo poomsae athletes and improve their front-kick and turning-side-kick motions.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.4
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• pp.253-261
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• 2021

This paper describes the process of evaluating maneuverability in still water of an unmanned surface vehicle based on data measured by performing sea trials. First, we set up a test scenario that is easy to analyze the maneuverability of the unmanned surface vehicle and to identify and verify the dynamics model. Since the attitude of hull varies according to the speed of the unmanned surface vehicle which has a planing hull shape, the relationship between waterjet RPM, speed and attitude is analyzed by performing straight forward tests at various speeds. The turning tests of the unmanned surface vehicle in which the waterjet angle rotates while turning are performed by changing the waterjet rotation angle under the condition of two representative speeds to analyze turning ability. The turning ability of the unmanned surface vehicle includes speed reduction, yaw rate, heel, and turing diameter at steady turning phase according to the speed and RPM.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.191-193
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• 2016

This paper proposes a voltage-controlled oscillator (VCO) that has broadband turning and low-level of phase noise characteristics. Due to the micro-strip line resonant circuit with a low Q value, which is applied to the broadband tuning range, the depreciated phase noise performance is compensated by restraining the harmonics of the oscillating frequency. The VCO was designed according to the proposed structure as well as the conventional structure, and the superiority of the proposed structure was verified through its simulation, fabrication, and measurement.