• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1613-1616
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• 2005

In this paper, we developed an algorithm of generating cam contour curve for hinge mechanism of folder-type mobile phone. The main feature of this hinge mechanism is that we can operate uniform torque to open or close the mobile phone. We divided the opening or closing intervals of the cam into finite sub-intervals, and then we determined the cam contour curve of each sub-interval as a parabolic curve. Finally, these finite parabolic curves form the total cam contour. We can design single cam, which composed moving cam with contour curve and fixed cam that plays only roller, and twin cam with contour curve that is made up the pair of two cams symmetrically.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.261-264
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• 1997

A single action press robot, which consists of a driving unit, rotator, up-down feed base and feed bar, is developed and applied for the press automation. The driving unit is made up with a face cam and blade cam, which have a phase angle. The feeding system consists of a double speed-up apparatus and linear motion guides, and has a fast motion characteristics. A horizontal feeding speed of the feed bar is increased twice by the double speed-up apparatus. The driving mechanism could be simplified due to the speed-up of the feeding unit.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.526-533
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• 1990

The dynamic stability of a single cam drive mechanism is investigated by an analytical approach. The nonlinear differential equation describing the motion of a single cam drive mechanism is linearized with respect to the imput power angle, and results a linear parametric differential equation. The instability region is examined by applying the harmonic balance method to linearized parametric equation having periodicity. Through the dynamic stability analysis of a single cam drive mechanism, it is observed that the parametric resonances exist and the instability regions tend to become wide as increasing the drive speed and follower mass.

• Journal of Pharmacopuncture
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• v.19 no.4
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• pp.344-349
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• 2016

Objectives: This study aimed to determine the knowledge levels and attitudes of School of Health and Vocational School of Health students toward complementary and alternative medicine (CAM). Methods: Three hundred thirty-three (333) students studying at the Mehmet Akif Ersoy University School of Health and the Golhisar Vocational School of Health in Burdur, Turkey, were included in the study. Research data were collected by using a survey method based on the expressed opinions of the participants. Results: Of the participants, 69.7% were female and 97% were single (unmarried). Of cigarette users and those with chronic illnesses, 46.8% and 47.8%, respectively, used CAM. Those using CAM were statistically more likely to be female (P < 0.021), to have higher grades (P < 0.007), to be single (P < 0.005), to be vocational school of health graduates (P < 0.008), and to have fathers at work (P < 0.021). While 9.6% of the students thought CAM to be nonsense, 10.8% thought that the methods of CAM should be tried before consulting a doctor. Conclusion: A majority of the students in the study population were found to use complementary and alternative medicine, but that they lacked information about its methods. As a way to address this, CAM should be included in the curriculum of schools that provide health education, and CAM training programs should be given to healthcare professionals to improve their knowledge of CAM. In Turkey, many more studies should be performed to determine nurses' and doctors' knowledge of and attitudes about CAM methods so that they can give correct guidance to society and take more active responsibility in improving patient safety.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.6
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• pp.1056-1063
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• 1994

In this paper a content addressable memory (CAM) is designed by adopting best-match method. It has a single processing element(PE) architecture with high computational efficiency and throughput. It is composed of three main functional blocks(input MUX, best-match CAM, control part). It support fully parallel processing. Logic simulation is completed by using QUICKSIM, Circuit simulation is performanced by using HSPICE. Its layout is based on the ETRI 3 m n-well process design rules. Its maximum operating frequency is 20 MHz.

• Journal of Technologic Dentistry
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• v.42 no.1
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• pp.45-53
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• 2020

Purpose: The purpose of this study was to investigate the current status and satisfaction of dental CAD/CAM system. Methods: A survey of dental technicians was conducted and a total of 353 responses were used for analysis. The satisfaction difference according to career was analyzed by ANOVA and tukey HSD (α = .05). Results: Satisfaction with the design program was 3.64 ± .86, the highest among all items. On the other hand, the satisfaction with price was 2.75 ± 1.02, which was the lowest. The difference according to career was statistically significant in the following items. Frequent breakdown, single crown margin, bridge crown margin, retentivity, price, A/S, equipment training (p<.05). Conclusion: As the materials applied to dental CAD/CAM are expanding and the types of prostheses are diversified, the use rate of CAD/CAM is continuously increasing. The dental CAD/CAM system will need to be improved in a way that will satisfy all patients, dentists and dental technicians.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.3
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• pp.275-283
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• 2006

Statement of problem. There have been many studies about marginal discrepancy of single restorations made by various systems and materials. However most of the statistical inferences are not definite because of sample size, measurement number, measuring instruments, etc, and there have been few studies about the marginal fit of the Digident CAD/ CAM zirconia ceramic crowns. Purpose. The purpose of this study was to compare the marginal fit of the anterior single restorations made by using the Digident CAD / CAM zirconia ceramic crowns with metal-ceramic restorations and to obtain more accurate information by using a large enough sample size and by making sufficient measurements per specimen. Material and Methods. The crowns were made from one extracted maxillary central incisor pre-pared with a 1mm shoulder margin and $6^{\circ}$ taper walls by milling machine. The in vitro marginal discrepancies of the digident CAD / CAM zirconia ceramic crowns and control groups(metal ceramic crowns) were evaluated and compared. Twenty crowns per each system were fabricated. Measurements of a crown were recorded at 50 points that were randomly selected for marginal gap evaluation. Parametric statistical analysis was performed for the results. Conclusion. Within the limitations of this in vitro study, the following conclusions were drawn: 1. Mean gap dimensions and standard deviations at the marginal opening for maxillary incisal crowns were $88{\pm}10{\mu}m$ for the control (metal-ceramic crowns), $92{\pm}4{\mu}m$ for Digident CAD / CAM zirconia ceramic crowns. 2. Marginal gap between Digident CAD / CAM zirconia ceramic crowns and metal ceramic crowns did not show significant difference (P>.05). 3. The Digident CAD/ CAM zirconia ceramic crowns and metal ceramic crowns showed clinically acceptable marginal discrepancy.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.800-806
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• 2013

The purpose of this study was to evaluate the marginal fitnesses on the effect of span length of bridge and the marginal gaps within the clinically allowed range. The samples were fabricated with zirconia core using CAD/CAM system. The test groups were divided by four groups, single crown, 2-units bridge, 3-units bridge and 4-units bridge and 10 zirconia cores per each group. The results of mean marginal gaps were $42.95{\pm}6.93{\mu}m$ in the single crown, $43.53{\pm}5.27{\mu}m$ in 2-unit, $53.43{\pm}13.38{\mu}m$ in 3-unit, and $50.85{\pm}8.25{\mu}m$ in 4-unit on each. The marginal gap of mesial and distal surfaces were statistically significant differences between single, 2-unit group and 3-unit, 4-unit group (p<.05) and this results was effected by the span length. The buccal and lingual surfaces were no statistically significant differences within all groups(p>.05). From this results the span length of the zirconia core may have influence on marginal fitness and the marginal gaps were within the clinically allowed range.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.975-978
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• 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
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• v.5 no.2
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• pp.43-49
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• 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.