• Tunnel and Underground Space
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• v.13 no.5
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• pp.362-372
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• 2003

Since the occurrence of Portland cement, a great number of concrete structures were constructed. But the concrete structures have their own life times, which inevitably demand repairing treatments, especially on their surface parts. Currently many various methods have been developed and are being applied fer this purpose. In this study, a newly developed method using pneumatic chipping machine and anchor pin was adopted far repair of old concrete structure and the mechanical characteristics of cementing plane between existing and new concrete were tested. Comparing the removal methods for the decrepit part of existing concrete using pneumatic chipping machine and hydraulic breaker, the peak cohesion was higher when using chipping machine at the cementing plane. On the other hand, the residual cohesion was higher for the case of breaker. Step shaped chipping on the cementing plane was effective in increasing peak cohesion, which results 14% increase in the case of 30 mm step height and 22% in 50 mm height when compared with planar chipping plane. The use of anchor pin increased the residual cohesion, which restricted shear slip on the cementing plane after peak shear stress and the tensile strength of 32% compared with that of non-anchored case. According to the combined effect of step shaped chipping of 30 mm and anchor pin with an interval of 15 cm, the peak cohesion reached up to 77% and the residual cohesion showed 180% of the ones of the fresh concrete, respectively.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.178-188
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• 2022

Interim immediate denture is fabricated to minimize the period of edentulousness after removal of the patient's remaining teeth and before delivery of final prosthesis. In the case of using the CAD/CAM system, there is an advantage in that the manufacturing process in the clinic and laboratory can be simplified by overcoming some of the limitations of manufacturing interim immediate dentures in the traditional way. However, there are also disadvantages in that errors occur in the process of transmitting information about the patient's intermaxillary relationship to the digital network of the laboratory, resulting in unstable occlusal relationships or non-esthetic prostheses. To overcome this problem, using the simple and accurate POP BOW system's occlusal plane digital transfer method, it was possible to fabricate an esthetic and functional 3D printed interim immediate denture after removal of the remaining upper and lower anterior teeth.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.2045-2049
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• 2008

In this paper, we propose an novel architecture for H.264 High Profile Encoder Intra Prediction module. This designed module can be operated in 306 cycle for one-macroblock. To verify the Encoder architecture, we developed the reference C from JM 13.2 and verified the our developed hardware using test vector generated by reference C. We adopt plan removal and SAD calculation to reduce the Hardware cost and cycle. The designed circuit can be operated in 133MHz clock system, and has 250K gate counts using TSMC 0.18 um process including SRAM memory.

• IEMEK Journal of Embedded Systems and Applications
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• v.19 no.1
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• pp.1-8
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• 2024

Robotic arms have been widely utilized in various labor-intensive industries such as manufacturing, agriculture, and food services, contributing to increasing productivity. In the development of industrial robotic arms, camera sensors have many advantages due to their cost-effectiveness and small sizes. However, estimating object positions is a challenging problem, and it critically affects to the robustness of object manipulation functions. This paper proposes a method for estimating the 3D positions of objects, and it is applied to a pick-and-place task. A deep learning model is utilized to detect 2D bounding boxes in the image plane, and the pinhole camera model is employed to compute the object positions. To improve the robustness of measuring the 3D positions of objects, we analyze the effect of lens distortion and introduce a false positive filtering process. Experiments were conducted on a real-world scenario for moving medicine bottles by using a camera-based manipulator. Experimental results demonstrated that the distortion removal and false positive filtering are effective to improve the position estimation precision and the manipulation success rate.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.239-246
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• 2010

When galvanized steel strip is produced through a continuous hot-dip galvanizing process, the thickness of the adhered zinc film is controlled by impinging a thin plane nitrogen gas jet. The thickness of the zinc film is generally affected by impinging pressure distribution, its gradient and shearing stress at the steel strip. These factors are influenced by static pressure of gas spraying at air knife nozzle, a nozzle-to-strip distance and strip and a geometric shape of the air knife, as well. At industries, galvanized steel strip is produced by changing static pressure of gas and a distance between the air knife nozzle and strip based on experimental values but remaining a geometric shape of nozzle. Splashing and check-mark strain can generally occur when a distance between the air knife nozzle and strip is too short, while ability of zinc removal can lower due to pressure loss of impinging jet when a distance between the air knife nozzle and strip is too long. In present study, buckling of the jet and change of static pressure are observed by analyzing flow characteristics of the impinging jet. The distance from the nozzle exit to the strip varies from 6 mm to 16 mm by an increment of 2 mm. Moreover, final coating thickness with change of a distance between the air knife nozzle and strip is compared with each case. An ability of zinc removal with the various distances is predicted by numerically calculating the final coating thickness.

• The korean journal of orthodontics
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• v.37 no.2 s.121
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• pp.125-136
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• 2007

Objective: Soft tissue changes due to orthodontic treatment has large individual variation. Therefore continuous evaluation during treatment is required. Patients with fixed orthodontic appliances often wonder if their lip positions will change after the removal of brackets, but only a few studies exist on this topic. The objective of this study was to evaluate the changes of the lips and perioral soft tissue after bracket removal. Methods: The sample used in this study was 19 males and 33 females. Cephalometric X-rays were taken at 3 stages - T1 (before debonding), T2 (just after debonding), T3 (1.5 months after debonding). Results: The lower lip was retruded immediately after debonding (T2-T1), and 1.5 months after debonding (T3-T2). The mean amounts of retrusion from the vertical reference plane (sG perpendicular line) were about 0.38 mm for the upper lip and 0.88 mm for the lower lip. Immediately after debonding, lip retrusion of females was greater than that of males. During the post-debonding period, lower lip of males was retruded more than that of females. Conclusion: Lips are retruded after bracket removal, and there is no gender difference 1.5 months after debonding.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1326-1329
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• 1995

An influences of gap clearance, pressure and applied voltage shape on breakdown characteristics are investigated by using a rod-to-plane electrode in $SF_6$ gas. In case of D.C and A.C, a corona stabilization effect increases the breakdown voltage remarkably for lower pressure than 0.2MPa, whereas incase of negative D.C this effect exists independently of gas pressure. This suggests that an insulation optimization in a pratical apparatus is needed to prevent a corona appearance through the removal of local field enhancement.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.273-276
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• 2002

Watershed boundary and stream network can be extracted from DEM(Digital Elevation Model) using GIS software such as ARC/INFO or ArcView Spatial Analyst. However, there exist many errors in the generated watershed boundary and stream network just by operating sink removal function of the present software. This paper present the error reducing method to delineate watershed boundary and generate stream network especially in plane areas by using stream burning techniques known as Fillburn and Agree bum. These preprocessing techniques of DEM dramatically decreased the errors comparing with the results by no-bum DEM.

• Journal of ILASS-Korea
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• v.9 no.3
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• pp.15-21
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• 2004

The removal of the dusts in the subway stations, tunnels, factories and buildings becomes issue for comfortable indoor and outdoor conditions. There has been used an automatic self-cleaning filter system to collect the dusts. In general, the collected particles are removed by water spray nozzles. The new design for improving the cleaning efficiency of collected dusts and reducing the supplied water is the concept of the plane array of demister filters and the twin-fluid nozzle for mixing compressed air and water in the automatic self-cleaning filter system. Results show that the cleaning efficiency of twin-nozzle filter systems is 99.1%, compared to 47% in the conventional filter system. Therefore the automatic self-cleaning filter system using twin-fluid nozzle filter systems reduces water supplied in the filter system, and increases cleaning efficiency and drying efficiency.

• Journal of Technologic Dentistry
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• v.15 no.1
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• pp.63-72
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• 1993

The following results were come out after the careful study on the rational application of dental surveyor in the clinic 1. The adequate path of placement satisfying guiding plane, retention non-interference and esthetics. 2. The location of clasp arm and the accurate under cut position and amount of clasp tip can be judged. 3. In case that the model needs to be mounted to the surveyor, the exactly same location can be attained by the means of the tripoding. 4. The unnecessary undercut areas in the path of placement and removal car be corrected. 5. The surveyor is essential in manufacturing dental prosthesis and it can also carry out all sorts of prospective designs In terms of the diagnosis and treatment.