• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.137-147
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• 2008

Recently, Power and thermal management are becoming major concerns in computer system design. The energy efficiency is an important attribute of the mobile and embedded systems. Today's powerful mobile processors needs more energy and longer battery life. Many research has been focused to reduce energy consumption for the mobile processors.In this paper, performance monitoring system for the Power-management techniques is implemented for Intel's XScale microarchitecture-based Marvell PXA320 processor on Windows CE platform. It also provides software interface for changing DVFS configuration. Performance and power consumption are measured for benchmark programs through performance counter value and voltage/current measurements on LabVIEW platform. By using the developed monitoring system, it is possible for dynamic power management to track processor's workload and to determine the actual power consumption.

• The Journal of the Korean dental association
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• v.58 no.7
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• pp.388-397
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• 2020

Objective: The purpose of the study was to calculate the effective and absorbed organ doses of cone-beam computed tomography (CBCT) in pediatric patient using personal computer-based Monte Carlo (PCXMC) software and to compare them with those measured using thermoluminescent dosimeters (TLDs) and anthropomorphic phantom. Materials and Methods: Alphard VEGA CBCT scanner was used for this study. A large field of view (FOV) (20.0 cm × 17.9 cm) was selected because it is a commonly used FOV for orthodontic analyses in pediatric patients. Ionization chamber of dose-area product (DAP) meter was located at the tube side of CBCT scanner. With the clinical exposure settings for a 10-year-old patient, DAP value was measured at the scout and main projection of CBCT. Effective and absorbed organ doses of CBCT at scout and main projection were calculated using PCXMC and PCXMCRotation software respectively. Effective dose and absorbed organ doses were compared with those obtained by TLDs and a 10-year-old child anthropomorphic phantom at the same exposure settings. Results: The effective dose of CBCT calculated by PCXMC software was 292.6 μSv, and that measured using TLD and anthropomorphic phantom was 292.5 μSv. The absorbed doses at the organs largely contributing to effective dose showed the small differences between two methods within the range from -18% to 20%. Conclusion: PCXMC software might be used as an alternative to the TLD measurement method for the effective and absorbed organ dose estimation in CBCT of large FOV in pediatric patients.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.11
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• pp.979-983
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• 2013

The three-dimensional measurement method of confocal systems is a spot scanning method which has a high resolution and good illumination efficiency. However, conventional confocal systems had a weak point in that it has to perform XY axis scanning to achieve FOV (Field of View) vision through spot scanning. There are some methods to improve this problem involving the use of a galvano mirror [1], pin-hole array, etc. Therefore, in this paper we propose a method to improve a parallel mode confocal system using a micro-lens and pin-hole array in a dual microscope configuration. We made an area scan possible by using a combination MLA (Micro Lens Array) and pin-hole array, and used an objective lens to improve the light transmittance and signal-to-noise ratio. Additionally, we made it possible to change the objective lens so that it is possible to select a lens considering the reflection characteristic of the measuring object and proper magnification. We did an experiment using 5X, 2.3X objective lens, and did a calibration of height using a VLSI calibration target.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.12
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• pp.1367-1374
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• 2008

A new high-gain Fabry-$P{\acute{e}}rot$ cavity antenna for wireless broadband internet(Wibro) base station antennas, which is covered with metamaterial superstrate presenting simultaneous negative values of permittivity and permeability, is proposed. To facilitate the fabrication process using the printed circuit board(PCB) technology of today, a new planar-type metamaterial superstrate is designed, which shows negative and low positive values of a refractive index near the Wibro service frequency band. And the principle of antenna gain enhancement is analyzed from the two different view points of effectively low refractive index and of the Fabry-$P{\acute{e}}rot$ resonance condition. Single square patch antenna is used as a feeder. The separation distance is determined by considering the reflection phases of the metamaterial superstrate and the substrate satisfying Fabry-$P{\acute{e}}rot$ resonance condition, respectively. Comparison between the prediction and the measurement shows good agreement, which verifies the validity of our design approach.

• Geotechnical Engineering
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• v.10 no.1
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• pp.71-82
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• 1994

According to the field measurement of dredging-reclaimed land, the actual self-weight consolidation settlement has been frequently reported to be less than the predicted values based on the laboratory tests results. The author estimates that one of the reasons is the reduction of the compressibility due to the sedimentation of the dredging material, Furthemore, the aging effect is ignored in the consolidation characteristics of the very low stress range as a pump dredging-reclaimed land. In this paper, a series of seepage consotidation tests has been carried out by applying the seepage force to the specimen prepared by sedimentation in consolidmeter in order to clarflfy the aging-effect on the compressibility of dredging clayey soil, Also, with a view to overcome unstable consolidation solution occurring in the case where the initial water content is higher as pumpdredging reclaimed land, the finite difference analysis technique using predictorforrector method is suggested that it gets good agreement with ezperimental results. Finally, the compressibility of the dredging clayey soil is depended on self-weight consolidation time.

• Journal of Families and Better Life
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• v.28 no.1
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• pp.99-118
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• 2010

This thesis is to inquire into the effect of group art therapy by way of reminiscence on the depression of the elderly inpatients with geriatric illness. The subjects are 20 inpatients whose age is over sixty in the Elderly Nursing Hospital located in K county. Among them, 10 inpatients are arranged as the experimental group, and the rest 10 inpatients, as control group. The research period is from February 28, 2009 to August 21, 2009. For the experimental group, the group art therapy by way of reminiscence is carried out during 21 sessions once a week for 60 minutes per session. For both the experimental group and the control group, pre and post test is carried out, and then after four weeks, the further test is carried out. The measurement tools are KGDS(Korean Form of Geriatric Depression Scale) and KHTP. The data are analyzed by SPSS(for Windows) and SAS(ver. 9.1.2), by which one-way ANOVA, two-way ANOVA, and Scheffe test are carried out. The results are as follows. First, the average of the whole elderly depression levels is shown significantly in the post test and the further test between the two groups. The art therapy group is more effective on the reduction of depression of the elderly inpatients with geriatric illness than control group. Second, it is shown that there is significant difference between the two groups in the the elderly depression by KHTP. The art therapy group is more effective in the improvement of the reduction of the elderly depression in view of KHTP. In conclusion, the group art therapy is an efficient intervention which enables to reduce the depression of the elderly inpatients with geriatric illness.

• Progress in Superconductivity and Cryogenics
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• v.14 no.2
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• pp.24-27
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• 2012

The superconducting coil system is one of the most important components in Korea Superconducting Tokamak Advanced Research (KSTAR), which has been operated since 2008. $Nb_3Sn$ and NbTi superconductors are being used for cable-in-conduit conductors (CICCs) of the KSTAR toroidal field (TF) and poloidal field (PF) coils. The CICCs are cooled by forced-flow supercritical helium about 4.5 K. The temperature, pressure and mass flow rate of the supercritical helium in the CICCs are interacting with each other during the operation of the coils. The complicate behaviors of the supercritical helium have an effect on the operation and the efficiency of the helium refrigeration system (HRS) by means of, for instance, pressure drop. The hydraulic characteristics of the supercritical helium have been monitored while the TF coils have stably achieved the full current of 35 kA. In other hands, the PF coils have been operated with various pulsed or bipolar mode, so the drastic changes happen in view of hydraulics. The heat load including AC loss on the coils has been analyzed according to the measurement. These activities are important to estimate the temperature margin in various PF operation conditions. In this paper, the latest hydraulic behaviors of PF coils during KSTAR operation are presented.

• Information Systems Review
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• v.8 no.2
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• pp.189-209
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• 2006

Business expects that IT investment would maximize the effects, like availability, timeliness, rapidity of information, by practical using of information technology for a strategic goal. However, it is not clear yet that IT investment would increase business productivity and could create profitability in the end-the linkage between IT investment and business KPI(Key Performance Indicator). In this case study(only provides post-evaluation case), we suggested integrated IT ROI(Return On Investment) methodology with a consistent and integrated view, on the base of practical implementation at Korean financial company. Especially, we evaluated connection between IT and business strategy, made business-related IT KPI development methodology, suggested framework for sustainable IT evaluation and management.

• Korean Journal of Human Ecology
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• v.18 no.3
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• pp.719-727
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• 2009

The ultimate success of commercial applications of body scan data in the apparel industry will be consumers' substantial applications such as automated custom fit, size prediction, virtual try-on, personal shopper services (Loker, S. et al., 2004). In this study, we surveyed fifty consumers and forty-seven apparel industry workers about their recognition and interest in 3D body scanning and virtual try-on. The results are as follows: 55% of the apparel industry workers has recognized 3D body scanning as a convenient technology, but do not know how to use it. To the questions regarding virtual try-on, 53% of the workers give positive answers. The consumers have a more positive view on virtual try-on than the workers do. The workers predict that the application of 3D body scan technology to the apparel industry could offer customers helpful information in their clothing selection by using virtual images of various size and style, and increase mass production of MTM(Made-To-Measure). The answers from the male consumers in their twenties indicate that virtual try-on is useful by 88% on offline shopping and by 100% on online shopping. 53% of the workers and 68% of the consumers gave answers that just by virtual try-on they could judge the quality of the apparel products and purchase them. Absolutely 3D virtual try-on is an effective tool for online shoppers. 85% of the workers anticipate applications of the 3D body scanning also in 'body measurement', 'custom pattern development' as well as 'virtual try-on' in the near future. With the positive reactions and the stimulating interests in virtual try-on, the conditions of contemporary world encourage more active researches and wide usages of the technology in apparel industry.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.97-103
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• 2018

Force is a crucial element to be measured in various industries, especially the machine tool industry. Mega units of force are required in fields such as the heavy and ship industries. Micro/nano units of force are required for microparticles. The detection of force generates a physical transformation due to the force imposed from the outside, atlrnd electrical voltage signals are obtained from the system. For the detection of force, an octagonal ring load cell based on circular ring theory is designed and produced. To design the octagonal strain ring, theoretical values with data from the ANSYS program are compared to determine the size of the octagonal strain ring. An octagonal strain ring of the chosen size is made with the SCM415 material. The strain gauges are attached to the octagonal strain ring, designed to construct a full Wheatstone bridge. The LabVIEW program is used to measure the data, and strain values are found. With the octagonal ring load cell completed in this way, experiments are conducted by imposing forces on the tangential axis and radial axis. Experiments are performed to verify if the octagonal ring load cell conducts measurements properly, and theoretical values are analyzed to find any differences. The data will later be used in further research to develop a machine-tool dynamometer.