• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.4
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• pp.375-387
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• 2015

This study investigates an economic and highly efficient power-converter topology and its modulation scheme for 60 kW rapid EV charger system. The target system is a three-phase three-switch buck-type rectifier topology. A new carrier-based PWM scheme, which is characterized by simple implementation using logic gates, is introduced in this paper. This PWM scheme replaces the diode rectifier equivalent switching state with an active switching state to produce the same effective current flowing path. As a result, the distortion of input current during the polarity reversal of capacitor line voltage can be mitigated. The proposed modulation technique is confirmed through simulation verification. The proposed modulation technique and its implementation scheme can expand the operation range of the three-phase three-switch buck-type rectifier with high-quality AC input and capacitor ripple current.

• Journal of Fashion Business
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• v.23 no.3
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• pp.1-9
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• 2019

The purpose of this study was to develop questions for fashion design development, by applying 7 elements of the scamper to the fashion design elements, and to present a scamper checklist of fashion design elements, and item structures. In this study, the scope of research was limited to clothing design among various fashion products, and among various design development stages. Fashion design development focusing on design sketching, was limited to the research scope. The research method was based on an empirical study that derived scamper questions through FGI (Focus Group Interview), consisting of 5 fashion experts. Fashion design elements applied to development of scamper questions consisted of silhouettes, constructive lines, structural details, decorative details, patterns and textures of fabrics, and item structures, derived by applying these elements to the individual 7 elements of the scamper: substitute, combine, adjust, modify, put to other uses, eliminate, and reverse. Results of the study included 7 questions for substituting, 8 questions for combining, 6 questions for applying, 15 questions for modifying, 4 questions for putting to other uses, 4 questions for eliminating, and 7 questions for reversal. The scamper checklist for fashion design elements and item structures drew to 5 lists of silhouette variations, 7 lists of constructive line variations, 11 lists of structural detail variations, 10 lists of decorative detail variations, 11 lists of fabric variations, and 9 lists of structural modifications of items.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.32 no.2
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• pp.51-62
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• 2021

Objectives: Tic disorder is a neurodevelopmental disorder characterized by multiple involuntary movements of muscles or vocalization. Although tic symptoms subside as the patient ages, some patients suffer from significant functional impairments related to severe tic symptoms. This manuscript aimed to review the latest scientific evidences for the effect of cognitive-behavioral interventions on tic disorder. Methods: The relevant studies were identified by searching medical research databases. We focused our search on studies published between 2000 and 2020 in order to reflect the latest scientific evidence. A total of 821 articles were identified in the initial database search and 27 articles were finally included for the review after the exclusion of duplicated and irrelevant articles. Results: Behavioral therapies including habit reversal training, Comprehensive Behavioral Intervention for Tics, and exposure and response prevention were the most widely studied interventions for tic disorder and are recommended as first-line treatments for tic disorders with high confidence. Cognitive psychophysiologic approaches were also reported to be effective. Conclusion: Further studies are needed to support the future treatment of tics with low-cost and more widely available treatments, in order to ensure better treatment outcomes.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.22-29
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• 2002

Usually, much harmonics are included and cause harmonic loss of motor, torque pulsation, electro-magnetic noise and shock etc. by switching function of inverter when drive induction motor variableness inside. It applied partial resonant Buck converter and three phase voltage type SPWM inverter circuit to induction motor driving system in this paper that see to solve such problem. Changed operation condition variously to do input current of circuit that propose sine-wave by unit power factor almost and capacitor supplied bringing back to life voltage by power supply arranging properly assistance diode and electric power switching. Power factor and efficiency improved as that minimize variation of input at power supply voltage polarity reverse by that add voltage reversal function. Also, by using output filter, reduced harmonic of output line to line voltage components, and introduce state space analysis and forecast operation of rectifier. Such all items confirmed validity through simulation and an experiment.

• The Journal of Korean society of community based occupational therapy
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• v.2 no.2
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• pp.61-69
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• 2012

Objective : The purpose of this study was to investigate the effect of left visual stimuli for reducing the severity of unilateral neglect. Method : This research used a reversal design(ABAB) of single case study. The subject was a 60-year-old male patient who had left unilateral neglect. Remedial approach is more valuable method than compensatory approach in term of reducing the unilateral neglect. One of the method of remedial approach is controlled sensory stimulation. Result : I performed the line bisection test before and after the stimulation, and while doing that, put blinking lights to the patient from the left side. The average errors in the line bisection test decreased in B B', the intervention period, compared with A A'. The MVPT left response behavior score increased from 13 to 18. Conclusion : This shows that the light stimulation is effective in the reduction of unilateral neglect.

• The korean journal of orthodontics
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• v.32 no.3 s.92
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• pp.227-234
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• 2002

In order to investigate the action mechanism of protein kinase C on $K^+$ channel in osteoblastic cell, effects of phorbol 12, 13-dibutyrate on human osteoblast-like cells (G292) were studied by patch clamp technique with cell-attacked configuration. 111 this experiment, 45pS ion channel was dominant in G292 cell line according to their approximate conductances in symmetrical 140mM KCl saline at holding potential of 60mV. In torrent-voltage relationship, reversal potential was 5.5mV at the condition of potassium enriched saline in the pipette and -27 mV at the condition of standard extracellular saline In the pipette. Phorbol 12, 13-dibutyrate 10nM increased the open probability of 45pS channel and staurosporine, an inhibitor of protein kinase C, suppressed this effect. Phorbol 12,13-dibutyrate moved the reversal potential of 45pS channel to more negative potential and increased the single channel current at the same membrame potential. In order to check the activation of protein kinase C in G292 cell by phorbol 12,13-dibutyrate, western blot of protein kinase C was performed. Phorbol 12,13-dibutyrate $0.1{\mu}M$ translocated protein kinase C from cellular compartment to membrane compartment of the cell. These findings suggest that phorbol 12,13-dibutyrate, one of phorbol esters, activate 45pS channel In G292 cell and affect cell membrane potential, that regulate cellular function.

• The Journal of the Acoustical Society of Korea
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• v.40 no.5
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• pp.417-427
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• 2021

Long-range communication in deep waters must overcome the low data rate due to limited bandwidth. This paper presents the performance of Multiple-Input-Multiple-Output (MIMO) system to increase the data rate. In MIMO system, communication performance is degraded by crosstalk between users and an adaptive passive Time Reversal Processing (TRP) is widely used to eliminate this. In October 2018, long-range underwater acoustic communication experiment was conducted in deep water (1,000 m ~) off the east of Pohang, South Korea. During the experiment, a vertical line array was utilized and communication signals modulated by binary phase shift keying and quadrature phase shift keying with a symbol rate of 512 sps were transmitted. To generate MIMO communication signals, received signals from ranges of 26 km and 30 km is synthesized. Compared to the conventional passive TRP, the adaptive passive TRP eliminates the crosstalk between users and achieves error-free performance with an increase of output signal-to-noise ratio. Therefore, two users separated by 4 km in range achieves an aggregate data rate of 1,024 symbols/s.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.792-795
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• 2005

The guide-ways of precision machine tools are one of important element of machine tools. It has usually a pair of surfaces for constraint of one direction with bearing. In the case of precision machine tools, non-contact bearing such as hydrostatic bearing and aerostatic bearing is adopted usually. In this case, profiles of rails has effect on straightness and the clearance of bearing has effect on stiffness of guide way, which changes to higher if clearance changes to smaller. The clearance is varied along moving table according to relative distance of pair of rails. The relative distance of pair of rail can be divided by three properties. First and second properties are straightness of each pair of rail and bearing pad. And, third is parallelism about pair of rails and pairs of bearing pad. There are several methods for measuring straightness of each surface such as reversal method, sequential two point method, and way straightness. These straightness measuring methods are always acquiring deviation of profile from eliminating linear fitted inclined line and don't have the information of parallelism. Therefore, to get the small clearance for high stiffness, the straightness of rail and bearing pad and parallelism about pair of rails and pair of bearing pads are measured for correction such as regrinding, reassembling and lapping. In this research, new and easy method for measuring parallelism of pair of rails is suggested. Two displacement probe and sensor stage, which is carry on the displacement sensor, are needed. The simulation and experiment was accomplished about pair of horizontal guide way to confirm the measurement of parallelism. And, the third probe is added to measure the straightness of each rails by sequential two point method. From the estimation of combined these two methods, it is confirmed that the profiles of a pairs of rails can be measured.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.288-294
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• 2009

Various polymer electrolyte membrane fuel cell (PEMFC) startup procedures were tested to explore possible techniques for reducing performance decay and improving durability during repeated startup-shutdown cycles. The effects of applying a dummy load, which prevents cell reversal by consuming the air at the cathode, on the degradation of a membrane electrode assembly (MEA) were investigated via single cell experiments. The electrochemical results showed that application of a dummy load during the startup procedure significantly reduced the performance decay, the decrease in the electrochemically active surface area (EAS), and the increase in the charge transfer resistance ($R_{ct}$), which resulted in a dramatic improvement in durability. After 1200 startup-shutdown cycles, post-mortem analyses were carried out to investigate the degradation mechanisms via various physicochemical methods including FESEM, an on-line $CO_2$ analysis, EPMA, XRD, FETEM, SAED, FTIR. After 1200 startup-shutdown cycles, severe Pt particle sintering/agglomeration/dissolution and carbon corrosion were observed at the cathode catalyst layer when starting up a PEMFC without a dummy load, which significantly contributed to a loss of Pt surface area, and thus to cell performance degradation. However, applying a dummy load during the startup procedure remarkably mitigated such severe degradations, and should be used to increase the durability of MEAs in PEMFCs. Our results suggest that starting up PEMFCs while applying a dummy load is an effective method for mitigating performance degradation caused by reverse current under a repetition of unprotected startup cycles.

• Journal of the Korean Society of Costume
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• v.61 no.2
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• pp.20-31
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• 2011

Decentralization is an effort to liberalize people from its character of neutralizing or restraining people while indwelling in the previous thought system. Decentralization in fashion is one of the phenomenon of post-modernism fashion, and it is closely related to de-culturalism, crossover, abolition of rank, and etc, and it is in line with Asian look which includes orientalism fashion. The study intends to consider the Phenomenon of Decentralization of Asian Look and its Method depicted in the western fashion. The study focuses on documentary data, and the it is held with the basis of Asian look shown in western fashion. If ideology which influenced the formation of folk costume of Asia, Asian look is the dissolution of such ideology, and post-modern amusement is substituting it. The most conspicuous characteristic of decentralization phenomena of Asian look is pastiche which is a combination and reallocation of external style of many cultural zones and many folk costumes, and it shows mutual irrelevance, and it is a neutral imitation which has internal meaning and humor disappeared. Also, Asian look shows characteristics of parody and irony, which are reversal characteristics of aesthetic value which is expressed through methods of addition, modification, distortion, exaggeration, inversion, dissolution, and etc. Parody which is expressed through imitation regarding previous style shows effect of humor or satire, but its characteristics show that it expresses respect or admiration regarding the original The method of irony is showing sarcasm with ironical method regarding the peculiar style of Asian folk costume, and it pursues unexpected shock and joy, and it is closely related to orientalism fashion. Expansion and constancy of Asian look reflects the interest regarding folk of Asia and Asia, and it is a movement which intends new attempt by abolishing stereotype, and furthermore, it is expressing liberty of humans.