• Transactions of the Society of Information Storage Systems
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• v.2 no.2
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• pp.123-129
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• 2006

The head to disk spacing must be decreased to increase recording densities in hard disk drives. Recently, to decrease the head to disk spacing, smooth disk having no bumps onto the lading zone has used. In this research, we compared the number of particles generated ill HDD with smooth and textured disks. We used a sampling method using a particle sampler and a CPC (condensation particle counter) to detect particles in HDD. First, we sampled and counted particles generated with disk rotational speed and various rest times when the smooth disk and textured disks were used, then analyzed the sampled particles by SEM (scanning electron microscopy) and AES (auger electron spectroscopy). In results of measuring particles, more particles in case of LZT disk drive generated than that of the smooth disk drive in all test modes. The number of particles generated in the smooth disk was very low. The particle generation increased as the rest time increased (smooth/LZT disks) and more particles in case of LZT disk drive generated than that of the smooth disk drive. In results of analyzing particle components, Al, Ti, Si components were detected and we could not found differences between components in case of smooth/LZT disk drive.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.554-557
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• 2010

Pay Per Drive System can be a new solution for improving the traffic congestion and air pollution by not only taxing on the driving distance but also taxing different proportion with driver' s location and time. Thus it gives us new concept of the area and time of traffic jam, as a result, we can find a natural and efficient transportation mechanism and reduced air pollution. Also this system can trace the driver' s location by GPS, it can provide Black Box function on every car on the road. We propose the method of advanced transportation service by Pay Per Drive System.

• Journal of Information Science Theory and Practice
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• v.9 no.2
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• pp.33-46
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• 2021

The purpose of this paper is to analyze the case of 'drive-thru' services newly introduced and tried in libraries in Korea under the influence of COVID-19, and to develop and propose a service model so that this service can be continuously applied to all libraries in the future. Therefore, the method of study was selected and analyzed by selecting one of the representative libraries that provide related services in Seoul Special City, Incheon Metropolitan City, and Anyang City of Gyeonggi Province. In addition, a focus group interview was conducted with twelve people in charge to find a way to apply the drive-thru service to the library. As a result, the library's drive-thru service is a way to fulfill the library's original purpose of providing information materials while minimizing faceto-face contact with users. It was concluded that it is a suitable method for a library of complex buildings, where there is a lack of parking space. In addition, it was deduced that it may be one of the ways to use the library efficiently for office workers who are unable to use library services during the opening hours. Therefore, if the drive-thru service is implemented according to the developed model, it is expected to increase the library visit rate and data utilization rate.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.4
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• pp.39-45
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• 2010

Because of portable storage device's technical improvement, it's speeding up the conversion of mass storage. It means it's easier to move and save data. Generally, USB is using for portable storage device and forensic perspective, it's possible us to study data drain through portable storage device under securement of using vestige of USB. If we can secure using vestige of USB from boot domain it's possible to investigate data drain & prove criminal act. This thesis is suggesting Key/Thumb drive & USB Drive Enclosure's confirmation of using or not and division way though Disk Signature analysis.

• Journal of Cadastre & Land InformatiX
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• v.51 no.1
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• pp.39-51
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• 2021

Recently, there has been much interest in practical use of standardized HD map that can effectively define roads, lanes, junctions, road signs, and road facilities in autonomous driving. Various kinds of de jure or de facto standards such as ISO 22726-1, ISO 14296, HERE HD Live map, NDS open lane model, OpenDRIVE, and NGII HD map are currently being used. However, there are lots of differences in data modeling among these standards, it makes difficult to use them together in autonomous driving. Therefore, we propose a data model conversion method to enable an efficient use of various kinds of HD map standards in autonomous driving in this study. Specifically, we propose a conversion method between the NGII HD map model, which is easily accessible in the country, and the OpenDRIVE model, which is commonly used in the autonomous driving industry. The proposed method consists of simple conversion of NGII HD map layers into OpenDRIVE objects, new OpenDRIVE objects creation corresponding to NGII HD map layers, and linear transformation of NGII HD map layers for OpenDRIVE objects creation. Finally, we converted some test data of NGII HD map into OpenDRIVE objects, and checked the conversion results through Carla simulator. We expect that the proposed method will greatly contribute to improving the use of NGII HD map in autonomous driving.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.713-717
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• 2001

This paper focuses on a network model for GCTs which can be used to investigate high power circuits with or without using RC-snubbers. The series connection of GCTs is commonly applied in the high power inverter field. Here expensive and space-consuming snubbers are applied, to overcome the problem of an asymmetric distribution of the blocking voltage among the single GCTs. As an alternative to large snubbers, a new active gate drive concept is proposed and investigated by simulation.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.216-222
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• 2003

Today we have excellent motor drive system using high frequency carrier PWM control voltage source inverter in the other hand, we have met serious problems caused by high frequency switching. PWM Cyclo-converter called Matrix converter is expected as the new strategy Possible to improve these problems and add some more convenient features suitable for new drive system. in this Paper, we will introduce the background, features and outline of this converter, and additionally introduce some remarkable activity on this converter

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.239-243
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• 1989

This paper represents the control software development for Direct Drive Arm Robot with the WHILE language composed the 68000 assembly language and high level language modula-2. Direct Drive Ann Robot needs the control program which is fast step and exactly position moving because Direct Drive Arm Robt depends on accuracy. We found that the self-tuning algorithm for this robot control is very good for the real time control and the floating point operation using the 32 bit CPU(MC 68020) controller.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.332-336
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• 1998

Recently, the BLDC(Brushless DC) motor has been increasingly applied to home appliance and the study of BLDC motor drive is extensively processing, so it is necessary to investigate the characteristic of the BLDC motor drive. In this paper, we proposed the modeling of interior permanent - magnet BLDC motor drive. The state model of motor and the model of inverter using pulse width modulation are included. The modeling is verified by the experimental results.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.856-859
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• 2003

The switched reluctance motor(SRM) drive system provides a good adjustable speed and torque characteristics. However, because of the torque production mechanism, it also has some disadvantage such as higher torque ripple and fluctuation in speed. To reduce torque ripple and to control speed precisely, digital signal processor(BSP) is adopted. The DSP TMS320F241 was used to be realized this drive system. Test results show that the suggested control system has the ability of dynamic and precise speed control.