• 한국공작기계학회논문집
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• 제11권6호
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• pp.1-9
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• 2002

This study describes the geometric characteristics and the 5-axis machining method in order to make end mill cutter coming with insert tips. End mill geometry is consisted of flute part and insert tip part. Flute part modeled by using ruled surfaces with constant helix angle, and insert tip part modeled by rectangular planes containing tapped hole of specified direction in its center. In this study, the modeled insert tip part considered both of a radial rake angle and a axial rake angle, because they were important cutting conditions. In order to machining the virtual end mill defined from geometric characteristics, we programmed a special software to machining the end mill considered in this study. This software can generate NC-codes about following processes, end milling or ball end milling of flute part end milling of rectangular plane, centering of hole, drilling of hole, and tapping of hole. Ant sampled end mills were modeled and machined on 5-axis CNC machining center with two index tables. Since machined end mills were very agreeable to designed end mills, we saw that the method proposed in this study can be very useful for manufacturing of end mill body with insert tip.

• 대한인간공학회지
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• 제25권3호
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• pp.67-75
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• 2006

HVIMs consists of simulated driver models implemented with series of mathematical functions and computerized vehicle dynamic models. To effectively model the perception process, as a part of driver models, psychophysical nonlinearity should be considered not only for the single-modal stimulus but for the stimulus of multiple modalities and interactions among them. A series of human factors experiments were conducted using the primary sensory of visual and auditory modalities to find out the effects of auditory cues in visual velocity estimation tasks. The variations of auditory cues were found to enhance/reduce the perceived intensity of velocity as the level changed. These results indicate that the conventional psychophysical power functions could not applied for the perception process of the HVIMs with multi-modal stimuli. 'Ruled surfaces' in a 3-D coordinate system(with the intensities of both kinds of stimuli and the ratio of enhancement, respectively for each coordinate) were suggested to model the realistic perception process of multi-modal HVIMs.

• 보존과학회지
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• 제36권4호
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• pp.296-305
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• 2020

Konbaung Dynasty was the last unified dynasty that ruled Myanmar from 18^th to 19^th century. During this time Buddhist art flourished in Myanmar due to the interest of the rulers toward their traditional culture. Metal decorative artifacts in the 18^th century are classified into structures and Buddha statues. They are further subdivided into gilt-bronze and bronze objects, depending on their material component. Three-dimensional gilt-bronze decorative artifacts were cast with a brass alloy of Cu-Zn-Sn-Pb and their surfaces were gilded with extremely thin gold leaves (less than 1 ㎛ in thickness). The gilded layer approximately comprised 10 wt% silver in addition to the main element, gold. The lack of Hg in the gilded layer, indicated that the amalgam gilding technique was not applied. The analysis results indicated that the lacquered gilding technique was applied to the objects. Bronze decorative artifacts without gilding were cast with materials containing Cu-Sn-Pb. The bronze pavilions and bronze Buddha staues were crafted using the same alloy of high-tin bronze, which approximately contained 20 wt% Sn. No heat treatment was applied to reduce the brittleness of the objects after they were cast with a large amount of Sn. The most significant difference between the gilt-bronze and bronze decorative artifacts lie in their elemental compositions. The gilt-bronze decorative artifacts with their gilded surface were manufactured using brass containing zinc, while the unplated bronze decorative artifacts were composed of bronze containing tin. Artifacts of the same type and size are classified differently depending on the materials utilized in the surface treatment such as gilding.