• Transactions on Electrical and Electronic Materials
• /
• v.18 no.5
• /
• pp.279-286
• /
• 2017

In this paper, an optimal approach for the wide-area regulation of control devices in a transmission network is proposed. In order to realize an improved voltage profile and reduced power loss, existing devices such as tap-changing transformers, synchronous machines, and capacitor banks should be controlled in a coordinated and on-line manner. It is well-understood that phasor measurement units in transmission substations allow the system operators to access the on-line loading and operation status of the network. Accordingly, this study proposes efficient software applications that can be employed in area operation centers. Thus, the implanted control devices can be regulated in an on-line and wide-area coordinated approach. In this process, efficient objective functions are devised for both voltage profile improvement and power loss reduction. Subsequently, sensitivity analysis is carried out to determine the best weighting factors for these objectives. Extensive numerical studies are conducted on an IEEE 14-bus test system and a real-world system named the Azarbayjan Regional Transmission Network. The obtained results are discussed in detail to highlight the promising improvements.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.16 no.3
• /
• pp.315-320
• /
• 2006

There are many types of reduction drives for industrial applications. In general, high precision speed reducer which has a cycloid or involute teeth profile, used to in robot. Because, it is essential to use precision reduction drives for accuracy of position control on robot system. In this paper, we propose a robot speed reducer(RSR) with straight line teeth profile, which has basically a triangle teeth profile. In new straight line teeth profile, we have a good result for strength, stress and stiffness by using finite element analysis and the results indicate that variation of eccentric coefficient affects the optimal tooth motion, and it can lower the stress and noise.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.17 no.7
• /
• pp.952-956
• /
• 2007

In industrial site, as the technology of FA developes, many robots can take the place of human labor. Generally, robots require high precision reducers which have cycloid or involute tooth profile. These reducers provide high reduction ratios with low backlash and high accuracy but need a high stiffness of tooth. In this study, to improve the high precision, the cycloid reducers which have straight line teeth profile are used. Also the FEM analysis, which consist of straight line teeth profile, was performed to simulate the stress of teeth profile.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.41
• /
• pp.31.1-31.7
• /
• 2019

Background: To test the hypothesis that in profile smiling view, for ideal aesthetics, a tangent to the labial face of the maxillary central incisor crowns should be approximately parallel to the true vertical line and thereby perpendicular to the true horizontal line. Methods: An idealized female image was created with computer software and manipulated using the same software to construct an "ideal" female profile image with proportions, and linear and angular soft tissue measurements, based on currently accepted criteria for idealized Caucasian profiles. The maxillary incisor labial face tangent was altered in 5° increments from 70 to 120°, creating a range of images, shown in random order to 70 observers (56 lay people and 14 clinicians), who ranked the images from the most to the least attractive. The main outcome was the preference ranks of image attractiveness given by the observers. Results: The most attractive inclination of a tangent to the labial face of the maxillary incisor crowns in profile view in relation to the true horizontal line was 85°, i.e. 5° retroclined from a perpendicular 90° inclination. The most attractive range appears to be between 80 and 90°. Excessive proclination appeared to be less desirable than retroclination. Beyond 105° most observers recommend treatment. Conclusion: In natural head position, the ideal inclination of the maxillary incisor crown labial face tangent in profile view will be approximately parallel to the true vertical line and thereby approximately perpendicular to the true horizontal line.

• Imaging Science in Dentistry
• /
• v.39 no.4
• /
• pp.185-189
• /
• 2009

Purpose : The purpose of this study was to investigate how to detect proximal caries using line profile and validate linear measurements of proximal caries lesions by basic digital manipulation of radiographic images. Materials and Methods : The X-ray images of control group (15) and caries teeth (15) from patients were used. For each image, the line profile at the proximal caries-susceptible zone was calculated. To evaluate the contrast as a function of line profile to detect proximal caries, a difference coefficient (D) that indicates the relative difference between caries and sound dentin or intact enamel was measured. Results : Mean values of D were $0.0354{\pm}0.0155$ in non-caries and $0.2632{\pm}0.0982$ in caries (p<0.001). Conclusion : The mean values of caries group were higher than non-caries group and there was correlation between proximal dental caries and D. It is demonstrated that the mean value of D from caries group was higher than that of control group. From the result, values of D possess great potentiality as a new detection parameter for proximal dental caries.

• Journal of the Korean Society for Precision Engineering
• /
• v.31 no.8
• /
• pp.697-703
• /
• 2014

This paper is study of solving vibration problem occurred in moving hand of wafer transfer robot in semiconductor manufacturing line. Long settling time for decreasing vibration makes low production rate, and moreover the excessive vibration of hand sometimes breaks the wafer in a cassette. The ways of reducing the moving speed and changing the type of motion profile did not help for lessening vibration. Therefore, we analyzed the mechanical property of the hand such as natural frequency, and frequency component of the motion profile currently used in the manufacturing line. In several conditions of motion profile, we found the best condition of which the frequency component in near of natural frequency of the hand is minimal and this induced small vibration in moving hand. The results were verified theoretically and experimentally using frequency analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.975-978
• /
• 2001

For machining auto-mobile cam, the developed biarcs-fitting method eliminates the ridge problems in conventional straight-line fitting approximation or single-arc fitting of curve tool path where it leaves ridges of tool marks on the machined surface of the workpiece. The powerful advantage of this biarc method is demonstrated by applying it to the numerically controlled machining of a curved cam profile, also verified by using a CNC simulating program for auto-mobile cam profile. As a result, this algorithm may be used in CNC milling and turning for cam profile machining with short block line.

• Journal of Power System Engineering
• /
• v.5 no.2
• /
• pp.43-49
• /
• 2001

For machining auto-mobile cam, the developed biarcs-fitting method eliminates the ridge problems in conventional straight-line fitting approximation or single-arc fitting of curve tool path where it leaves ridges of tool marks on the machined surface of the workpiece. The powerful advantage of this biarc method is demonstrated by applying it to the numerically controlled machining of a curved cam profile, also verified by using a CNC simulating program for auto-mobile cam profile. As a result, this algorithm may be used in CNC milling and turning for cam profile machining with short block line.

• 제어로봇시스템학회:학술대회논문집
• /
• 1999.10a
• /
• pp.194-197
• /
• 1999

Automatic weld bead removal system is consisted of bead removal tool, bead profile measurement system and tool motion control system. In this paper, design of weld bead profile measurement system which is used for automatic weld bead removal system is described. The system measures the weld bead position, normal vector of the auto-body and weld bead profile. The optical sensor with structured laser beam is used as a sensor and comparison of the sensor that can be used for this purpose is discussed in detail. The measurement process and the related software developed for this purpose are also described. A median filter, average filter and long line filters are used and their effects in bead profile measurement are discussed. The measurement system is integrated into automatic bead removal system and is used to remove weld bead in rear pillar of automotive body. The whole system operates well in automotive body assembly line and thus the system is proved to be good for this purpose.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.2 no.1
• /
• pp.23-27
• /
• 1972

A roentgenographic cephalometric study was made on the soft and hard tissue profile of Korean adults. The subject consisted of 52 males and 54 females from 17 to 22 years of age and with normal occlusion and acceptable profile. Twenty one landmarks were plotted and two oriented lines named SnH line and SnV line were drawn on the tracings of all cephalograms. The means and the standard deviations from the subjects were calculated in each measuring category and the means were compared with those of male and femal samples. The results were obtained as follow: 1. In depth and height, individual variations and sex differences of the lower facial profile were larger than the upper face. 2. The sex differences of upper facial profile were larger in height than depth. 3. The individual variations and sex differences of the top of nose were the smallest in all measuring points. 4. The thickness of the soft tissue of upper face and upper lip in male sample were larger than those of female, but the same matter were not found in mental region.