• Korean Journal of Culture and Social Issue
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• v.12 no.1
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• pp.55-79
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• 2006

This study is interested in aberrant driver behaviour. The aim of this study is to investigate the effect of error and lapse on driving behaviour of elderly drivers. In order to estimate the errors and lapses, 'Driver Behaviour Questionnaire(DBQ) was used and tested with 883 drivers. Among them 175 of young drivers(younger than 25) and 150 of elderly drivers(older than 65) answered their driving patterns; driving history, annual mileage, the frequency of committing traffic violation, and experience of accident within 5 years. Elderly driver's data were collected by face to face interview. The factors of aberrant driver behaviour were analyzed and the DBQ score was compared by the age. The aberrant driver behaviour was consisted of 3 factors; violations, errors and lapses. Elderly driver's DBQ score was lower than young driver's. Elderly and young drivers showed longer driving history. were in low DBQ score group. Elderly drivers had high error score and young drivers had high violation score. Young driver's aberrant driving behaviour was associated with annual mileage, the frequency of committing traffic violation. Elderly driver's aberrant driving behaviour was associated with annual mileage, experience of accident. Specially elderly drivers, whose violation, error, lapse score was high answered more committing experience of accident within 5 years.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.361-369
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• 2020

With the increasing role of environmental design in promoting urban safety, new design attempts have been made to improve pedestrian safety in crosswalks. This study proposes an evidence-based design solution for improving crosswalk function by conducting simulations and field experiments. Drivers with more than one-year driving experience participated in this study. Four different crosswalk design patterns were prepared: (1) a zebra pattern, (2) zebra pattern with colored triangles, (3) 3D pattern, and (4) art pattern with unique colors and design. The results supported that the zebra pattern with colored triangles could be the most effective solution for crosswalk design by increasing visibility, attention, deceleration, and landscape aesthetics. This study provided objective data to support the performance of various crosswalk patterns and suggested the need to reevaluate the present crosswalk design guidelines.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.899-906
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• 2005

It is known that an oscillating airfoil can Produce a driving force through the generation of a reversed $K\'{a}rm\'{a}n$ vortex street, and this can be expected to be a new highly effective propulsion system. The wake formation behind the heaving airfoil was visualized and was measured using PIV systems We have been examined various conditions such as frequency number, amplitude in NACA 0010. As Strouhal number is greater than 0.08. wake profile with velocity deficit can be transformed into the wake with velocity excess After evaluating vortex center flow patterns in the wake investigated using tracking trajectories in temporal evaluation of the shedding vortices. We also Presented the experimental results on the unsteady vortices structure of the heaving airfoil at various parameters.

• Journal of Technology Innovation
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• v.11 no.2
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• pp.283-314
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• 2003

The transformation of sector system in Information and Communications Technology (ICT), a prominent character in sector system, has been paid much attention in innovation theory with rapid change in information technologies and technological environment. In this context, we explore how Sectoral Innovation System (SIS) in ICT has been transformed since 1970 by employing US patent data and Proxy variables which measures the basic elements for SIS and its technological characteristics. By utilizing patent data, it is demonstrated that technological regimes, key links and Schumpeterian patterns of innovation in overall ICT sector have drastically transformed over the last three decades. We also reviewed how changes of knowledge bases and technological characteristics driving forces of dynamics in ICT help heterogeneous agents interact with environmental factors (Industrial structure and institutions), leading to industrial or economic growth and its dynamics in the historical perspective over ICT sector (Telecommunication, Computer and Semiconductor). Consequently, our research shows clearly that Schumpeterian patterns of innovation have shifted from Mark I to Mark II in ICT. Our study also provides a glimpse picture of dynamics patent data.

• Journal of the Korea Society for Simulation
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• v.14 no.1
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• pp.1-8
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• 2005

In the semiconductor manufacturing, yield enhancement is an urgent issue. It is ideal to prevent all the failures. However, when a failure occurs, it is important to quickly specify the cause stage and take countermeasure. Reviewing wafer level and composite lot level yield patterns has always been an effective way of identifying yield inhibitors and driving process improvement. This process is very time consuming and as such generally occurs only when the overall yield of a device has dropped significantly enough to warrant investigation. The automatic method of failure pattern extraction from fail bit map provides reduced time to analysis and facilitates yield enhancement. The automatic method of failure pattern extraction from fail bit map provides reduced time to analysis and facilitates yield enhancement. This paper describes the techniques to automatically classifies a failure pattern using a fail bit map.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1455-1460
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• 2000

When a tube is oscillated at a resonant frequency, acoustic variables such as density, velocity, and pressure undergo very large perturbation, often described as nonlinear oscillation. In order to analyze these phenomena, nonlinear governing equation has been drived and solved numerically. Numerical simulations were accomplished to study the effect of the tube shape on the maximum pressure we can obtain. The tubes of cylindrical, conical, and cosine-shape, which have same volume and length, were investigated. Results show that the resonant frequency and patterns of pressure waves strongly depend on not only the tube shape but also the amplitude of driving acceleration. The degree of non-linearity of wave patterns was also measured by the newly defined nonlinear energy ratio of the pressure signals. It was found that the 1/2 cosine-shape tube is more suitable to induce high compression ratio than other shapes.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.70.2-70.2
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• 2019

Recent observational works have reported spiral wave patterns (SWPs) in sunspots, but there is a lack of samples to derive the physical properties. In this presentation, we suggest the automatic method to detect the SWPs in observational data and present their statistical properties. From our method, we find more than 1000 SWPs observed by the Atmospheric Imaging Assembly onboard in the Solar Dynamic Observatory from 2013 to 2018. From our samples, more than half of the SWPs has the one spiral arm. The predominant oscillation period is 2 to 3 minutes. The rotating direction of the spiral arms does not depend on the latitude and the polarity of the sunspots. Our statistical results support the physical model suggested by Kang et al. (2019) that explain the generation of SWPs as the depth of the wave driving source and azimuthal modes in the straight vertical magnetic flux tube.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.902-905
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• 2006

Plasma Display Panels(PDPs) suffer from motion artifacts because of subfield driving method. In this paper, a modified motion compensation method is proposed. We apply the optimized mapping table to the higher subfield group and the fill-up method to the lower subfield group to generate optimum mapping patterns. This method does not concentrate 'on' mappings on higher subfields. Therefore it can possibly become a more robust motion compensation.

• ETRI Journal
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• v.31 no.4
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• pp.463-465
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• 2009

In this letter, we present an event stream processing system that can evaluate a pattern query for a data sequence with predicates. We propose a pattern query language and develop a pattern query processing system. In our system, we propose novel techniques for run-time aggregation and negation processing and apply our system to stream data generated from vehicles to monitor unusual driving patterns.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.101-104
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• 1996

A new detecting system for moving objects of coastal region has been designed by directional antenna and driving circuits. The designed system has been investigated by CAD for linear and planar antenna arrays of various radiating elements for antenna simulations and by P-spice of device simulations. For detecting the displacement of moving objects, we constructed four wideband dipole antenna, diode switching circuit, mixer, filter and amplifier. The results of antenna receiver were shown a possibility of distance measuring system through phase difference of radiation patterns in antenna simulation