• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.457-459
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• 2005

Low viscosity LCs have been developed for fast response time improvement of the TFT-LCD Monitors based on TN mode. This low viscosity characteristic s cause the pretilt angle to be changed and the uniformity to degrade. We have studied on the pretilt angle effect by the various components used for low viscosity LCs. We prepared the panels by using these various components and measured pretilt angle for this research. As a result of this research, we have found out that each low viscosity component has the different pretilt angle level and uniformity. For good display quality, it is important to keep the stable pretilt angle. The low viscosity LCs with this stable pretilt angle make it possible to prepare the high performance TFT-LCD Monitor with both fast response time characteristics and good display quality

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.827-833
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• 2022

In this study, the prediction of the bending angle for the 350 A bellows-type expansion joints and the structural stability according to the load were determined. The stability of the 2km piping system was predicted by applying the allowable bending angle of the expansion pipe joint obtained from the analysis. The maximum bending angle was calculated through bending analysis of the bellows-type expansion joints, and the maximum bending angle by numerical calculation was about 1.8°, and the maximum bending angle of the bellows obtained by comparing the allowable strength of the material was about 0. 22°. This angle was very stable compared to the allowable bending angle (3°) of the expansion pipe joint regulation. By applying the maximum bending angle, the allowable maximum deflection of the 2 km pipe was about 3.8 m. When the seismic load was considered using regression analysis, the maximum deflection of the 2km pipe was about 142.3mm, and it was confirmed that the bellows-type expansion joints and the deflection were stable compared to the allowable maximum deflection of the pipe system. These research results are expected to present design and analysis guidelines for the construction of piping and the development of bellows systems, and to be used as basic data for systematic research.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.175-187
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• 1998

The purpose of this study was to predict the prognosis of class III malocclusion treatments. 25 patients selected for this study were devided into two groups by the stability of dentitional, skeletal and soft tissue profile improvement. One was stable group which consisted of 12 children and the other was relapse group with 13 children. Various measurements in initial lateral cephalogram were calculated and analyzed by t-test, correlation coefficient and discriminant analysis. The results of this study were summarized as follows 1. In both stable and relapse groups, there was not distinct difference in the antero-posterior skeletal relationship (P<0.05). 2. As the result of wits, hn to occlusal plane angle and occlusal plane to mandubular plane angle, the occlusal plane of relapse group was stepper than that of the stable group. 3. In correlation coefficient analysis, the overjet and the occlusal plane to mandibular plane angle showed significant correlations (p<0.001, p<0.01). 4. The discriminant function was obtained from three major influential measurements; overjet, AB to occlusal plane angle and articular angle, and this function could discriminate correctly in 88% of these samples.

• Korean Journal of Applied Biomechanics
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• v.14 no.2
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• pp.15-26
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• 2004

The purpose of this study was to investigate the kinematic variables of peters motion in parallel bars. The subjects were 3 male national gymnasts. For this study, kinematic data were collected using video camera. Coordinate data were low-pass filtered using a fourth-order Butterworth with cutoff frequency of 6Hz. Each valuables analyzed was used to compare kinematic features between the subjects. The conclusions were as follows; 1. For a stable regrasp motion, the subjects appeared to increase horizontal and vertical displacement during the DS phase because it induce a vertical elastic of body and reaction of bar for the US phase. 2. For a stable hand standing motion of the regrasp, the subjects appeared to maintain the fast vertical and horizontal velocity during the DS phase, but in contrary during the US and Air phase the vertical and horizontal velocity appeared to do decrease. 3. When the arm lean angle and the trunk lean angle maintain a big angle during the DS phase, the subjects appeared to do a stable performance to release in a high position.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.15-19
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• 2000

The exact estimation of the ductile crack growth in a thin sheet would be needed in part of the commercial transport aircraft industry fields. A 2-dimensional elastic plastic finite element analysis was carried out to simulate a stable crack extension in a thin sheet 2024 aluminium alloy. Two kinds of crack modeling were used to evaluate curves of the stable crack extension. And then CTOA(crack tip opening angle) and CTED(crack tip energy density) were calculated in order to determine whether they can be used as useful crack extension criterions in a thin sheet. Results indicate that stable crack extension behaviors were simulated well and CTED is more admirable even though CTOA also is reasonable as a criterion for a stable crack extension in a thin 2024 aluminium alloy sheet.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.4
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• pp.185-192
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• 2001

In SRM drive, the ON·OFF angles of each phase switch should be accurately controlled in order to control the torque and speed stably. The accuracy of the switching angles is dependent upon the resolution of the encoder and the sampling period of the microprocessor, that are used to provide the information of the rotor position and to control the SRM power circuit, respectively. However, as the speed increases, the amount of the switching angle deviation from the preset values is also increased. Therefore, the low cost encoder suitable for the practical and stable SRM drive is proposed and the control algorithm to provide the switching signals using the simple digital logic circuit is also presented in this paper, As a result, a stable high speed SRM drive can be achieved by the high resolution switching angle control and it is verified from the experiments that the proposed encoder the logic controller can be a powerful candidate for the practical low cost SRM drive.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.993-995
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• 2002

Switched Reluctance Generator attracts much attention because of high effciency, simple controllability with traction drive. But the theories that have been adopted as SRG control methods are complicated up to the present. This paper proposes reference current limitation strategy for stable generation of SRM and switching angle control. The proposed method is verified by simulation and experiments.

• Korean Journal of Applied Biomechanics
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• v.15 no.2
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• pp.11-20
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• 2005

This study has a purpose on contributing to apprehend safe and right way to stop to the inline skate beginners and to the instructors who teaches line skating on the basis for the result of the kinematical analysis on Heel brake stop movement of the inline skate, focusing on the displacement on COG, angle displacement of ankle joint, angle displacement of knee joint, angle displacement of hip joint, using a 3D image method by DLT. To achieve this goal, we analysed the kinematical factor of the 3 well-trained inline skating instructors and obtained the following results. 1. During the movement of heel-brake stop, when strong power was given to a stable and balanced stop and the lower limbs, if the physical centroid is lowered the stability increases, and if it is placed high from the base surface, as the stability decreases compared to the case of low physical centroid, we should make a stop by placing a physical centroid in the base surface and lowering the hight of physical centroid. 2. To make a stable and balanced stop and to provide a strong power to the lower limbs, it is advisable to make a stop by decreasing an angle displacement of ankle joint during a "down" movement. In case of the left ankle joint, in all events and phases the dorsiflexion angle showed a decrease. Nevertheless, in the case of the right ankle joint, the dorsiflexion angle shows an increase after a slight decrease. The dorsiflexion angle displacement of ankle joint can be diminished because of the brake pad of the rear axis frame of the right side inline skate by raising a toe, but cannot be more decreased if certain degree of an angle is made by a brake pad touching a ground surface. To provide a power to a brake pad, it is recommended to place a power by lowering a posture making the dorsiflexion angle of the left ankle joint relatively smaller than that of the right ankle. 3. To make a stable and balanced stop and to add a power to a brake pad, the power must be given to the lower limbs in lowering the hight of physical centroid. For this, it is recommended to make a down movement by decreasing the flexion angle of a knee joint and it is necessary to make a down movement by a regular decrease of the angle displacement of knee joint rather than a swift down movement in every event and phase. 4. The right angle displacement of hip joint is made by lowering vertically the hight of physical centroid as leaning slightly forward. If too narrow angle displacement of hip joint is made by leaning forward too much, the balance is lost during the stop by placing the center in front. To make a stable and balance stop and to place a strong power to the lower limbs, it is recommendable to make a narrow angle by lower the hip joint angle. However, excessive leaning of the upper body to make the angle too narrow, can cause an instable stop and loss of physical centroid. After this study, it is considered to assist the kinematical understanding during the heel brake stop movement of the inline skate, and, to present basic data in learning a method of stable and balanced stop for the inline skating beginners or for the inline skate instructors in the present situation of the complete absence of the study in inline skating.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.129-137
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• 2006

The treatment plan for orthognathic surgery must be based on accurate predictions, and this can be produced the most esthetic, functional and stable results. The purpose of this study was aimed to evaluate the amount and interrelationship of the gonial angle and the mandibular width change after the mandibular setback surgery in the mandibular prognathic patients. Twenty patients were selected who received orthognathic surgery after presurgical orthodontic treatment. The patients with skeletal and dental Class III malocclusion were operated upon with bilateral sagittal split ramus osteotomy and mandibular setback. The lateral and posteroanterior cephalometric radiographs were taken preoperatively, postoperative 1 day and 12 months later after the orthognathic surgery, and then the gonial angle and mandibular width were measured. The computerized statistical analysis was carried out with SPSS/PC program. The gonial angle at postoperative 1 day was decreased about $5.3^{\circ}$ than preoperative value and the gonial angle at postoperative 12 months was increased about $1.4^{\circ}$ than postoperative 1 day. So the gonial angle at postoperative 12 months was decreased about $3.9^{\circ}$ than preoperative value. The mean preoperative gonial angle was $125.35^{\circ}{\pm}7.36$, showing significantly high value than normal and mean gonial angle at postoperative 12 months was $121.45^{\circ}{\pm}6.81$, showing value near to normal. The mandibular width at postoperative 1 day was decreased about 1.1 mm than preoperative value and the mandibular width at postoperative 12 months was more decreased about 1.7 mm than postoperative 1 day. So the mandibular width at postoperative 12 months was decreased about 2.8 mm than preoperative value. These results indicate that sagittal split ramus osteotomy in mandibular prognathic patients with high gonial angle is effective to improvement of gonial angle. It is considered to be helpful for maintenance of postoperative stable gonial angle area that detailed postoperative care and follow-up.

• The Journal of the Korean dental association
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• v.21 no.12 s.175
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• pp.985-990
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• 1983

320 cephalometric roentgenograms of 25 boys and 15 girls which was longitudinally taken from the age 6.5 to 13.5 have been analyzed to access the angular growth changes of the mandible. The statistical analysis of the results allowed the following conclusions. 1. Gonial angle was reduced with ageing. 2. Chin angle was reduced with ageing. 3. Occlusal plane to mandibular plane angle was relatively stable. 4. Lower incisor to occlusal plane angle was reduced and showed the greatest variability.