• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2877-2883
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• 2010

The folding kinetics of $WT^*$ ubiquitin variant with valine to alanine mutation at sequence position 26 (HubWA) was studied by stopped-flow fluorescence spectroscopy. While unfolding kinetics showed a single exponential phase, refolding reaction showed three exponential phases. The semi-logarithmic plot of urea concentration vs. rate constant for the first phase showed v-shape pattern while the second phase showed v-shape with roll-over effect at low urea concentration. The rate constant and the amplitude of the third phase were constant throughout the urea concentrations, suggesting that this phase represents parallel process due to the configurational isomerization. Interestingly, the first and second phases appeared to be coupled since the amplitude of the second phase increased at the expense of the amplitude of the first phase in increasing urea concentrations. This observation together with the roll-over effect in the second folding phase indicates the presence of intermediate state during the folding reaction of HubWA. Quantitative analysis of Hub-WA folding kinetics indicated that this intermediate state is on the folding pathway. Folding kinetics measurement of a mutant HubWA with hydrophobic core residue mutation, Val to Ala at residue position 17, suggested that the intermediate state has significant amount of native interactions, supporting the interpretation that the intermediate is on the folding pathway. It is considered that HubWA is a useful model protein to study the contribution of residues to protein folding process using folding kinetics measurements in conjunction with protein engineering.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.6
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• pp.675-687
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• 2009

In general, the forming process of the curved hull plates consists of sub tasks, such as roll bending, line heating, and triangle heating. In order to complement the automated curved hull forming system, it is necessary to develop an algorithm to classify the curved hull plates of a ship into standard shapes with respect to the techniques of forming task, such as the roll bending, the line heating, and the triangle heating. In this paper, the curved hull plates are classified by four standard shapes and the combination of them, or saddle, convex, flat, cylindrical shape, and the combination of them, that are related to the forming tasks necessary to form the shapes. In preprocessing, the Gaussian curvature and the mean curvature at the mid-point of a mesh of modeling surface by Coon's patch are calculated. Then the nearest neighbor method to classify the input plate type is applied. Tests to verify the developed algorithm with sample plates of a real ship data have been performed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.3115-3123
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• 1993

This paper presents a real-time correction method of the movemont errors of a translatory precision machine axis. This method is a null-balances technique in which two plane mirrors are used to generate an interferometric fringe pattern utilizing the optical principles of TwymanGreen interferometry. One mirror is fixed on a reference frame, while the other is placed on the machine axis being supported by three piezoelectric actuators. From the fringe pattern, one translatory and two rotational error components of the machine axis are simultaneously detected by using CCD camera vision and image processing techniques. These errors are then independently suppressed by activating the peizoelectric actuators by real-time feedback control while the machine axis is moving. Experimental results demonstrate that a machine axis can be controlled with movement errors less than 10 nm in vertical straightness, 0.1 arcsec in pitch, and 0.06 arcsec in roll for 50mm travel by adopting the real-time correction method.

• International Journal of Knowledge Content Development & Technology
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• v.9 no.1
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• pp.57-79
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• 2019

This study attempts to seek a solution, in terms of brain science, to stimulate reading activities of men to whom no attention has been given from the field of reading. In order to do so, brain pattern, reading tendency, reading preference, reading effectiveness and influence of reading were analyzed. As a result of the analysis, first, it showed that respondents' characteristics did not affect brain patterns, but school and social influences on reading were found to affect brain patterns. Second, reading propensity according to gender was observed to be different in terms of personal health, personal self - esteem, and cultural artistry. On the other hand, reading effectiveness was found to be different in terms of reading engagement and the willingness to continue reading whereas reading propensity according to the brain pattern was different in books related to humor and family matters. Third, reading satisfaction, reading engagement and willingness to continue reading all were observed to affect the reading activities of men. Suggesting measures to stimulate reading activities of men based on such findings, first, implementing dynamic reading education programs and finding reading models for men are needed. Second, when selecting books for reading program operations, books should be recommended according to gender rather than being selected en bloc by libraries. Third, since reading education at home shows high influences on both male and male-type brain pattern, the starting point of reading education should be made at homes. In particular, fathers, who can become a role model for men, need a reading role model, and reading education programs for fathers are also required.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.272-273
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• 2013

Some living thingsuse micro- or nano- structures for living in nature. Scientists and engineers made efforts to mimic them, and they succeeded in making new types of applications. They used 'Namib desert beetle' to self-filling device by moisture harvesting and 'lotus leaf' to self-cleaning device by water repelling. 'Namib desert beetle' and lotus leaf have micro-patterns on their surface, which consists of hydrophobic or hydrophilic materials [1]. Moreover, micro-patterns on the surface make self-filling or self-cleaning property enhanced because of the surface roughness. Surface roughness enhances wettability [2]. Micro-pattern is a significant factor to make the surface be functional, so we want to make new types of functional surface by micro-patterning. In this work,we make several functional micro-patterns (radial, line, and dot arrays) using maskless lithography and analyze the characteristics of each micro-pattern. In order to analyze and understand surface characteristics, micro-patterns with varying sizes are investigated. All experiments are proceeded on mr-DWL5 photo resists coated on silicon wafers in same condition. All the experiments have demonstrated good performances about hydrophobic or hydrophilic property corresponding to their material and structural combinations. In radial micro-pattern, although the surface is flat, water drops on hydrophilic radial pattern can be convergent to a middle point and water drops on hydrophobic radial pattern can be divergent from the middle point. In line array micro-pattern, water drops can roll off along only one direction in parallel with the line arrays. Such phenomena might be mainly caused by the local change of surface roughness. From these results, controlling the movement and direction of water drops is made feasible without introducing a slope, which can potentially be used for new types of applications.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.106-114
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• 2022

This study attempted to empirically investigate the difference in the Advertising Acceptance Attitudes of pre-roll advertisements according to the Use Motivation and Use Intensity of YouTube, which act as important factors in using YouTube. For this study, a survey targeted to both male and female university students was conducted, 200 people's data being used for the analysis. First research result was that positive attitude towards advertisement based on the Youtube Use Motivation was higher for the group who pursue narrative identities than the group who habitually use intention and pursue amusement. For avoidance behavior, the group who habitually use intention and pursue amusement was higher than the group who pursue narrative identities. Second, for the positive attitude towards advertisement based on Youtube Use Intensity, the group with higher Use Intensity showed an optimistic attitude relative to the group with lower Use Intensity. However, there was no difference in the avoidance behavior for advertisement. These following results imply that a strategy considering the Use Pattern based on the Use Motivation and Use Intensity of the users is needed in enforcing YouTube pre-roll advertisements.

• Journal of the Korean Magnetics Society
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• v.1 no.2
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• pp.74-78
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• 1991

The method for analyzing the recording and reading process of magnetic recording system by numerical simulation is introduced. which can simulate the effect of elements of the magnetic recording system. During the whole simulation, hysteresis characteristics must be included. Preisach model and finite element method are used to construct the algorithm. From the wave of recording current, recorded pattern of magnetization in recording media is simulated in recording process, and then waveform of reading signal in head coil is obtained in reading process. To show the validity of this method, this is applied to perpendicular magnetic recording system. Waveform of recording signal and reproduced signal is obtained in several density. Pattern of reprocuced voltage magnitude according to increase of recording density shows roll-off curve.

• Laser Solutions
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• v.17 no.4
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• pp.20-23
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• 2014

In printed electronics, printing rolls are used to transfer electronic ink onto a flexible substrate. Generally printing rolls are patterned in microscale by the indirect laser method. Since based on the wet etch process, the indirect method is neither environment-friendly nor suitable for making a printing roll with patterns narrower than $20{\mu}m$. In this paper, we have directly engraved micro-patterns into a Zn-coated metal specimens using a picosecond laser in order both to engrave $10{\mu}m$-wide patterns and to improve the pattern profile. Experiments showed that it is possible to engrave $10{\mu}m$-wide patterns with an a rectangular-shaped profile which is necessary for the dimensionally accurate printing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1A
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• pp.27-33
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• 2000

Gardner’s algorithm is one of the useful algorithm for NDD(Non-Decision Directed) symbol synchronization in PAM communications. But the algorithm has a weak point such as pattern noises increasing in multi-level PAM. To insert a pre-filter in the algorithm is able to reduce timing jitter and pattern noise. In this paper, we analyze statistical properties of NDD algorithm to find an optimal parameter of the pre-filter for improving timing jitter and PLL locking. As a simulation result, optimum value of pre-filter parameter, $\beta$, is 0.3 and 0.5 at the roll off factor of the channel, $\alpha$, is 0.5 and 1.0, respectively. Optimum parameters of the pre-filter for clock synchronization of all-digital 256-QAM demodulator is shown in the results.

• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.50-53
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• 2005

The turbulent flow around a sphere was investigated in a streamwise meridian plane using two experimental techniques: smoke-wire flow visualization in wind tunnel at Re=5,300 and PIV measurements in a circulating water channel at Re=7,400. The smoke-wire visualization shows flow separation points near an azimuthal angle of $90^{\circ}$, recirculating flow, transition from laminar to turbulent shear layer, evolving vortex roll-up and fully turbulent eddies in the sphere wake. In addition, the mean flow pattern extracted by particle tracing method in water tunnel at Re= 14,500 reveals two distinct comparable toroidal(not closed) vortices in the recirculation region. The mean velocity field measured using a PIV technique demonstrates the detailed wake configuration of close symmetric recirculation and near-wake configuration with two toroidal vortices, reversed velocity zone and vorticity contours.