• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.31-37
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• 2015

A laser line welder using a solid-state laser (Yb:YAG) has been manufactured for joining ultra-thin cold-rolled steel coils in steelworks. The coils to be welded primarily range from 0.15 to 0.3 mm in thickness and 800 to 1,100 mm in width. Because the steel plate is extremely thin, it is very important to control the stop positions of the clamp at cutting and welding points. In this study, both hydraulic proportional control valves and LVDT sensor embedded cylinders were used to precisely control and monitor the positions of clamps with complementary stoppers. As a result, the positions could be controlled within an error of ${\pm}30{\mu}m$. Erichsen cupping tests on the welded joints show that the Erichsen index ranges from 4.4 to 4.6 mm. Furthermore, the tensile strength of welding points is comparable to that of the base metal.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.1
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• pp.109-114
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• 1995

The purpose of this study was to investigate the changes of the shape of the panoramic innominate line and also to examine the relation of the panoramic innominate line to maxillary posterior wall according to positional changes in panoramic radiographs of the patients who had no pathoses in the maxillary sinus and adjacent bony structures. Thus these panoramic radiographs were obtained and evaluated in standard, forward 10mm, backward 10mm, chin down 10°, and chin up 10° positions. And the following results were obtained : 1. Panoramic innominate lines were not changed in shape according to various positional changes in panoramic radiography. 2. The panoramic innominate line was observed to be more clear images and decreased distance to the posterior wall of maxillary sinus at forward 10mm and chin down 10° positions. And the panoramic innominate line was observed more blurred images and increased distance to the posterior wall of maxillary sinus at backward 10mm and chin up 10° positions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7A
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• pp.775-780
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• 2004

In this paper, we propose a simple protection scheme for error prone bit positions of turbo codes using the error detection capability of the CRC, which is almost always employed in practical systems. The proposed scheme based on bit flipping with CRC offers flexibility on selecting the level of protection. Also, not having send additional parity bits or discarding useful bit positions, it offers the best error performance for a given level of protection.

• Korean Journal of Applied Biomechanics
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• v.27 no.1
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• pp.67-74
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• 2017

Objective: The purpose of this study was to apply a general linear model in statistics to marker position vectors used to study human joint rotational motion in biomechanics. Method: For this purpose, a linear model that represents the effect of the center of hip joint rotation and the rotation of the marker position on the response was formulated. Five male subjects performed hip joint functional motions, and the positions of nine markers attached on the thigh with respect to the pelvic coordinate system were acquired at the same time. With the nine marker positions, the center of hip joint rotation and marker positions on the thigh were estimated as parameters in the general linear model. Results: After examining the fitted model, this model did not fit the data appropriately. Conclusion: A refined model is required to take into account specific characteristics of longitudinal data and other covariates such as soft tissue artefacts.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.183-188
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• 2003

This study is to make the fundamentals of sound quality evaluation in regard of acoustical characteristics of passenger compartment. The deviation of frequency response function level within audible frequency is evaluated at receiving point in the research of room acoustics. In this study, frequency response function is the one between speaker and driver's ear positions. The positions of driver and audio speakers are optimized by analysis of acoustic mode of acoustic cavity. The main reflection planes are determined by analysis sound ray path diffused at optimized speaker positions. Finally, designer selects acoustical material by analysis of absorption effect of acoustical materials on the main reflection planes in order to avoid to distortion and fluctuation of frequency response function..

• Korean Journal of Geomatics
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• v.2 no.2
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• pp.99-105
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• 2002

The accuracy of the Digital Photologging System, designed for the construction of the road Facility Database, highly depends on the positions and attitudes of the cameras from GPS/INS integration. In this paper, the development of a loosely coupled GPS/INS is presented. The performance of the system is verified through a simulation as well as a real test data processing. Since the IMU used in this study shows large systematic errors, the possible accuracy of the positions and attitudes of this low-performance IMU when combined with precise GPS positions are assigned. Currently, the integrated system shows the positional accuracy better than 5cm in real data processing. Although the accuracy of attitude based on real test could not be assigned at this time, it is expected that better than 0.5 degrees and 1.8 degrees for horizontal and down component are achievable according to the simulation result.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.11-18
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• 2011

This paper examines the categorical labeling of lexical pitch accent contrasts in North Kyungsang and South Cholla Korean listeners. It focuses specifically on investigating whether the pitch accent perception of adults and children has a dialect-specific effect. To evaluate the development of perceptual identification, slopes, intercepts, and positions at categorical boundaries were computed using a logistic regression function. The results showed that differences in slopes and intercepts were significant between North Kyungsang child and adult listeners, but the same was not the case for the positions at boundaries. As far as South Cholla child and adult listeners were concerned, there was a significant difference in slopes, but not intercepts and positions at boundaries. In the present study, the comparison of intercepts and slopes at the boundaries indicated developmental differences between North Kyungsang adult and child listeners. This improvement in categorical proportion seems to be a result of developmental changes in categorical perception. For South Cholla adult and child listeners, however, perception of the non-native contrast becomes less categorical.

• Journal of The Korean Astronomical Society
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• v.39 no.2
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• pp.31-40
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• 2006

Near-IR $H_2$ emission features in the northern region of the Orion A giant molecular cloud were observed in the $CO\;J\;=\;1\;{\rightarrow}\;0$ line in search of CO outflows. Out of the 30 sources surveyed, CO line wings were detected toward 28 positions, suggesting a strong correlation between $H_2$ jets and CO outflows. Blueshifted wings were detected toward 26 positions while redshifted wings were detected toward 15 positions, which suggests that there is a bias in the source selection. The bias is more severe in OMC 3 than in OMC 2. Since the protostars in OMC 3 are younger and more deeply embedded, the bias may be caused by the difference of extinction between blueshifted and redshifted outflows. Some physical parameters of the outflows were derived from the line profiles.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.339-344
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• 2003

The conformation of synthetic oligosaccharide can be elucidated by employing molecular modeling and highfield proton NMR (nuclear magnetic resonance) spectroscopy. Information with respect to the composition and configuration of saccharide residues and the sequence and linkage positions of the oligosaccharide can be obtained by employing a variety of one- and two-dimensional NMR techniques and molecular modeling. These techniques are also useful in establishing the solution conformation of the oligosaccharide moiety. This study is focused on the elucidation of linkage positions of synthetic trisaccharides, Gal(β1-4)Glc(β1-3)Glc, Gal(β1-4)Glc(β1-4)Glc and Gal(β1-4)Glc(β1-6)Glc.

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.47-53
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• 2008

In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.