• Imaging Science in Dentistry
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• 제47권2호
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• pp.93-97
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• 2017

Purpose: The purpose of this study was to evaluate the accuracy of panoramic imaging in measuring the right and left gonial angles by comparing the measured angles with the angles determined using a lateral cephalogram of adult patients with class I malocclusion. Materials and Methods: The gonial angles of 50 class I malocclusion patients (25 males and 25 females; mean age: 23 years) were measured using both a lateral cephalogram and a panoramic radiograph. In the lateral cephalograms, the gonial angle was measured at the point of intersection of the ramus plane and the mandibular plane. In the panoramic radiographs, the gonial angle was measured by drawing a line tangent to the lower border of the mandible and another line tangent to the distal border of the ascending ramus and the condyle on both sides. The data obtained from both radiographs were statistically compared. Results: No statistically significant difference was observed between the gonial angle measured using the lateral cephalograms and that determined using the panoramic radiographs. Further, there was no statistically significant difference in the measured gonial angle with respect to gender. The results also showed a statistically insignificant difference in the mean of the right and the left gonial angles measured using the panoramic radiographs. Conclusion: As the gonial angle measurements using panoramic radiographs and lateral cephalograms showed no statistically significant difference, panoramic radiography can be considered in orthodontics for measuring the gonial angle without any interference due to superimposed images.

• 한국정밀공학회지
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• 제18권9호
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• pp.186-191
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• 2001

Spinning process is a chipless metal forming method for axi-symmetric parts, which is more economical, efficient and versatile method for producing parts than the other sheet metal forming process such as stamping or deep drawing. In this study, a fundamental experiment was conducted to improve productivity with process parameters such as tool path, angle of roller holder($\alpha$), feed rate($\gamma$) and corner radius of forming roller(Rr). These factors were selected as variables in the experiment because they were most likely expected to hale an effect on spring back. The empirical results were analyzed to know how much spring back was affected by these factors. And also thickness and diameter distribution of a multistage cup obtained by spinning process were observed and compared with those of a commercial product produced by conventional deep drawing.

• 한국전문물리치료학회지
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• 제16권1호
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• pp.1-9
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• 2009

An abdominal drawing-in maneuver (ADIM) with a pressure biofeedback unit can be used to prevent excessive lumbar lordosis during bridging exercise. Therefore, in this research, the effects of an ADIM on lumbar lordosis and lower extremity muscle activity during bridging exercise were investigated in thirty healthy adults. Surface electromyography (EMG) and VICON system were used to collect kinematic data and muscle activity, respectively. A paired t-test was used to determine a statistical significance. The results showed as follows: (1) When performing bridging exercise with an ADIM, the height of the anterior superior iliac spine and greater trochanter decreased significantly (p<.05). (2) When performing bridging exercise with an ADIM, the trunk extension angle and pelvic angle increased significantly (p<.05). (3) When performing bridging exercise with an ADIM, the EMG signal amplitude increased significantly in the rectus abdominis, internal oblique abdominis, external oblique abdominis, medial hamstring, and lateral hamstring (p<.05). (4) When performing bridging exercise with an ADIM, the EMG signal amplitude decreased significantly in the erector spinae (p<.05). From the result of this research, an ADIM trained with pressure biofeedback unit during bridging exercise is effective to prevent excessive contraction of erector spinae, to limit excessive motion of pelvis from sagittal plane and to increase muscle activity of abdominal muscles and hamstring muscle.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.426-429
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• 2005

In this study, the formed tool is used to machine of bearing raceway and a shape compensation scheme is proposed to compensate for shape of it in turning process. It is introduced the conventional design method of the formed tool; a simple depth compensation method and a drawing compensation method. And it is performed to investigate in detail properties of the formed tool about a tool angle and problems of a turning process of bearing raceway using the formed tool. The applicability of the proposed scheme is examined by comparing the experimental results obtained by a new designed formed tool with those obtained by a conventional tool.

• 국제물리치료학회지
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• 제10권3호
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• pp.1862-1867
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• 2019

Background: The importance of postural stabilization and cervical mobilization in subjects with pain from the anterior head posture is drawing more attention. However, studies on head and neck stabilizing intervention after mobilization are lacking. Objective: To examine the effects of Kinesiotaping and posture setting exercise on forward head posture (FHP). Design: Crossover Study Design Methods: The subjects were 17 male and female college students in their 20s with FHP. They were randomized into the Kinesiology taping group (KTG) with 9 subjects and posture stabilizing exercise group (PSEG) with 8 subjects. The intervention was conducted for 4 weeks, and changes in pain, craniovertebral angle (CVA), and proprioception were observed before and after intervention. Results: Pain was significantly reduced in the KTG and PSEG both before and after intervention. CVA and proprioception were significantly increased only in the PSEG. The differences in CVA and proprioception between the two groups were significant. Conclusions: These findings suggest that the application of posture setting exercise could decrease pain, proprioceptive error and increase CVA on FHP.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.276-279
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• 2000

When high temperature superconducting tapes is fabricated using the PIT (Powder In Tube) method, the length of HTS tapes is increased more than 500 ${\sim}$ 1,000 times of initial powder packed billet. On mechanical processing, heterogeneous properties between the ceramic superconducting core and Ag/Ag alloy sheath occur the non-uniformity deformation as like sausaging that deteriorate the critical current properties of HTS tapes. In this study, we investigated the workability of Bi-2223/Ag/Ag alloy sheath tapes fabricated by the PIT method involving a number of different mechanical processes, multi drawing and rolling. In order to obtain the high critical current density and high uniformity of Bi-2223/Ag sheath tapes, the influences of powder packing density, drawing die angle and rolling parameters were studied. We found that the roll diameter is an important variable in the rolling process, as critical current of tapes rolled using 250 mm rolls was higher than that using 150 mm rolls.

• 대한기계학회논문집
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• 제13권4호
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• pp.660-669
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• 1989

본 논문에서는 쐐기형 다이를 이용한 판재의 인발에 대한 슬립라인장에서 스트레인을 구하는 방법을 제시하고 이로부터 가공중에 생길 수 있는 역학적 문제의 공학적 해석을 얻고자 한다.

• 패션비즈니스
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• 제15권1호
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• pp.63-79
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• 2011

This study examines the relationship between breast shape and brassiere construction through the comparative analysis of brassiere pattern on the breast shape. This researcher drew the brassiere pattern of developing a pre-study for Chinese female adults according to average size based on the four breast shapes. And then we measures brassiere pattern size and comparatively analyzes breast between size and shape. Comparative analysis results of brassiere patterns are verified differences of size and shape on the breast shape. Above all an angle of cup dart showed remarkable differences on the breast shape. An angle of cup dart isn't proportioned to breast size. An angle of cup dart for cone shape is bigger than dome shape. Because cone shape breast is protruded center part but dome shape breast have a shape of smooth curve like a half globe. So an angle of a cone shape breast cup dart is determined bigger than dome shape breast. For increasing the uplift effect of brassiere, brassiere pattern is different on the breast shape. And a brassiere pattern need different drawing methods about the angle of cup dart, breast inner side diameter, slope and so on. This study has an important significance that it established a mechanical relationship of breast shape and brassiere pattern.

• 대한기계학회논문집A
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• 제29권2호
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• pp.325-332
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• 2005

This paper presents a study on defects in pearlite lamella structure of high carbon steel by means of finite-element method(FEM) simulation. High carbon pearlite steel wire is characterized by its nano-sized microstructure feature of alternation ferrite and cementite. FEM simulation was performed based on a suitable FE model describing the boundary conditions and the exact material behavior. Due to the lamella structure in high carbon pearlite steel wire, material plastic behavior was taken into account on deformation of ferrite and cementite. The effects of many important parameters(reduction in area, semi-die angle, lamella spacing, cementite thickness) on wire drawing process can be predicted by DEFORM-2D. It is possible to obtain the important basic data which can be guaranteed in the ductility of high carbon steel wire by using FEM simulation.

• 한국자동차공학회논문집
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• 제14권4호
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• pp.192-198
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• 2006

The real-time simulator of a turning-type sluice gate actuated by the hydraulic cylinders is developed using a PC and a visual C++ program language. The real-time simulator receives the directional control valve signal selected by the operator using the mouse, updates the state variables of the turning-type sluice gate system responding to the control signal, and draws the moving figures of the sluice gate, cylinder, reserved water every drawing time on the PC monitor. Also, the operator can observe the sluice gate angle, cylinder force, cylinder pressures, and hydraulic power representing the operation of sluice gate system through the PC monitor every drawing time. The simulator can be a very useful tool to design and improve the turning-type sluice gate system.