• Journal of Power Electronics
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• v.1 no.1
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• pp.1-8
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• 2001

The elimination of a pole sensor is desirable due to the low-cost requirement, the compactness, and the applied drives. This paper proposes the algorithm for the initial pole-position estimation of a surface permanent magnet linear synchronous motor (PM-LSM), which is carried out under the closed loop control without a pole sensor and is insensitive to the motor parameters. This algorithm is based on the principle that the initial pole position (IPP) is estimated by the trigonometric function of the two reference currents. The effectiveness of the proposed algorithm is confirmed by testing a surface PM-LSM with large disturbance, which result shows that IPP is well estimated within a satisfied moving-distance and a shorter estimation taken-time even if large disturbance such as cogging and friction is existed.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.6
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• pp.187-193
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• 2004

In this paper, we proposed the GPS position data correction method for autonomous land navigation using vanishing point property and a monocular vision system. Simulations are carried out over driving distances of approximately 60 km on the basis of realistic road data. On a straight road, the proposed method reduces GPS position error by at least 63% within 0.5 m. However, the average accuracy of the method is not presented, because it is difficult to estimate it on other than a straight road in variable conditions.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.5
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• pp.134-142
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• 1994

An upper bound elemental technique (UBET) is applied to predict variations of neutral plane and optimal position of the initial billet for rib-wep shaped ring forging. In the analysis, the neutral plane position and velocity fields are determined by minimizing the total power consump- tion with respect to chosen parameters. The degree of die-cavity filling by initial billet-position and the variations of neutral plane by friction condition are investigated. Experiments have been carried out with pure plasticine billets at room temperature. The theoretical predictions of the forging load and the flow pattern are in good agrement with the experimental results.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.43-49
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• 2006

Nowadays, the thermal environments of classrooms are usually adjusted by the ceiling type air-conditioning system with a temperature sensor installed on inlet of an air-conditioner. However, it is not clear that the conventional temperature sensor position is proper to satisfy both thermal comport and energy saving in summer especially. Therefore, this study is aimed at finding out the best position of the temperature sensor on the purpose of the comfort thermal environment and energy saving. The different 5 positions for the temperature sensor are supposed in this paper to analyze thermal environment by CFD. From the analysis through the CFD simulations, the best position of the temperature sensor satisfying for both comfort thermal environment and energy saving is obtained.

• International Journal of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.84-94
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• 2018

The purpose of this study was to compare the balance ability at different foot positions using K A T 2000 (Berg, Inc, vista, CA.1994). Thirty (male 15, female 15) normal subjects participated in this study. All subjects were tested at a one leg position or a two leg position that were toe-in $25^{\circ}$, toe-out $25^{\circ}$, and $45^{\circ}$. The starting position was where the subject crossed their arms across the chest and flexed knees slightily. The results of each test were displayed on a screen in a score format, which indicated balance index. These collected data were analyzed by using one way ANOVA, and t-test. The results of this study were as follows: When changing the angle of the foot in the one-foot and two-foot standing positions, there was no statistically significant difference, but the balance performance with the foot rotated by $25^{\circ}$ was better than that with the foot rotated by $45^{\circ}$. When changing the direction of the foot in the one-foot and two-foot standing positions, there was no statistically significant difference, but the balance performance with the foot rotated laterally was better - except for the case when the foot was medially rotated by $25^{\circ}$ in the right-foot static standing position. When the feet were medially rotated by $25^{\circ}$ in the two-foot static standing position, and were medially rotated by $25^{\circ}$ and $45^{\circ}$ in the one-foot static standing position, the balance performance of females was better than that of males. In this study, it was found that the balance performance of the subjects changed when the position of the foot was shifted on an unstable base of support. However, there was little correlation between balance performance and the height, weight and foot length of the subjects. It is necessary to conduct a follow-up study targeting various age groups and those with various diseases using an unstable platform or applying different physical or visual conditions, such as the length of the legs. Physical therapists need to consider the position of the foot in clinical settings for a better balance training or assessment.

• Korean Architects
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• s.539
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• pp.16-17
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• 2014

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.411-414
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• 2002

This paper proposed new techniques of rotor position detection for Switched Reluctance Motor(SRM). This technique is very simple and easy to find out rotor position. The main idea uses the impulse responses which have different values between aligned and unaligned. In order to obtain the rotor position, the Impulse applied to the unenergized phases and their responses are analized to control the speed of SRM without shaft sensor, Experimental results verify the feasibility of the proposed method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.445-447
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• 2000

The terminal and core(wire conductor) in a Harness processing is connected by putting them in a applicator by virtue of a manual operation. A normal or abnormal condition of crimping connections is nearly determined by a skilled worker. In general, a skilled worker operates a press motor with a foot switch by pressing on foot and puts a wire conductor into a press with one hand. By doing so, sufficient efficiency is not obtained by a worker. In this paper, a basic study has done to make improve an efficiency by finding the normal arrangement out as to whether a terminal and wire conductor in Harness are placed on the right position or not with a quadrant plane photo position sensor.

• Archives of Craniofacial Surgery
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• v.20 no.6
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• pp.347-353
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• 2019

Most orbital surgeons believe that it's difficult to restore the primary orbital wall to its previous position and that the orbital wall is so thin that cannot be firmly its primary position. Therefore, orbital wall fractures generally have been reconstructed by replacing the bony defect with a synthetic implant. Although synthetic implants have sufficient strength to maintain their shape and position in the orbital cavity, replacement surgery has some drawbacks due to the residual permanent implants. In previous studies, the author has reported an orbital wall restoring technique in which the primary orbital wall fragment was restored to its prior position through a combination of the transorbital and transantral approaches. Simple straight and curved elevators were introduced transnasally to restore the orbital wall and to maintain temporary extraorbital support in the maxillary and ethmoid sinus. A transconjunctival approach provided sufficient space for implant insertion, while the transnasal approach enabled restoration of the herniated soft tissue back into the orbit. Fracture defect was reduced by restoring the primary orbital wall fragment to its primary position, making it possible to use relatively small size implant, furthermore, extraorbital support from both sinuses decreased the incidence of implant displacement. The author could recreate a natural shape of the orbit with the patient's own orbital bone fragments with this dual approach and effectively restored the orbital volume and shape. This procedure has the advantages for retrieving the orbital contents and restoring the primary orbital wall to its prior position.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.508-510
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• 2004

In this paper, we proposed the GPS position data correction method for autonomous land navigation using vanishing point property and a monocular vision system. Simulations are carried out over driving distances of approximately 60 km on the basis of realistic road data. In straight road, the proposed method reduces GPS position error to minimum more than 63% and positioning errors within less than 0.5m are observed. However, the average accuracy of the method is not presented. because it is difficult to estimate it in curve road or other road environments.