• Journal of Power Electronics
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• v.19 no.6
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• pp.1380-1392
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• 2019

Input filters are very important to matrix converters (MCs). They are used to improve grid side current waveform quality and to reduce the input voltage distortion supplied to the grid side. Due to the effects of the input filter and the output power, the grid side power factor (PF) is not at unity when the input power factor angle is zero. In this paper, the displacement angle between the grid side phase current and the phase voltage affected by the input filter parameters and output power is analyzed. Based on this, a new grid side PF unity compensation method implemented in the indirect space vector pulse width modulation (ISVPWM) method is presented, which has a larger compensation angle than the traditional compensation method, showing a higher grid side PF at unity in a wide output power range. Simulation and experimental results verify that the analysis of the displacement angle between the grid side phase current and the phase voltage affected by the input filter and output power is right and that the proposed compensation method has a better grid side PF at unity.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.169-177
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• 2007

Competitive international business environment has forced many firms to focus on supply chain management to cope with highly increasing competition. Hence the supplier selection is the most important decision of a company. Because it has a direct effect on cost reduction and quality, profitability and flexibility improvement of a company, so the right supplier selection significantly affect on the organization's efficiency and effectiveness and competitiveness. The primary research objects of this study is to evaluate an importance of supplier selection factors as an index and to present the evaluation model for supplier selection. For this purpose, this study adopts the AHP method to calculate the importance of supplier selection factors. In this study, 16 factors which affect on the supplier selection decision making are classified into three factors-product supply related factor, product related factor, management ability related factor.

• The Journal of Society for e-Business Studies
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• v.19 no.1
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• pp.15-42
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• 2014

Cloud storage service has the potential to be a core infrastructure for the future mobile and Internet service; thus related service providers have been investing in it and trying to attract as many users as possible. In addition, those need to find out what motivates the users to keep using their service not only to attract new customers but also to secure their subscribers. Therefore, this study will examine its relationship with user's motivation based on the extended TAM model with external variables for objective research about continuous use of cloud storage service. As a result, it was found that personal innovativeness, self efficacy, functional attributes, and psychological switching cost influence the continuous use of cloud storage service. Also, it is expected they can guide service providers to the right track when setting up their business strategy in the future.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.23-32
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• 2006

Window buttons located on a task bar provide information about windows that have been open as well as active. When the number of buttons on the task bar increases, the button size gets smaller and as a result, it is more difficult to identify. This study proposes new alternatives of presenting window buttons to search for a target button efficiently. An experiment was conducted to evaluate the usability of the new. Factors manipulated in the experiment include 'button arrangement methods' and 'order of buttons'. The 'button arrangement methods' factor is composed of three levels, 'one line', 'changeable line', and 'grouping buttons'. The 'order of buttons' factor is composed of three levels, 'fixed order', 'click-right', and 'order control by user'. The results showed that the main effects were significant in search time. In subjective satisfaction, the interaction effect was also significant. The results could be applied to the design of small screens such as PDA or cellular phones.

• Korean Institute of Interior Design Journal
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• no.1
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• pp.72-75
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• 1992

Lighting made interior space visible and to recognize space itself. Sp9ace and form are established not themselves , but lighting. and dextrous treatment of natural light accomplished poeteic space. Inflowing of lighting in interior space is main factor to decide space character and image . That was recognized in interior space through many centries. At this point, this study was described for that present inflowing of lighting adapting space character and right method in lighting program. The present study is to present the planning method of the most appropriate and the most rational natural lighting in planing for lighting. Under this premise the followings are made ; I. An introduction , the purpose, the sphere, and the method of this study are stated. II, The present writer studied the general characteristics of natural lighting. III. this author studied the factor of decision on control and representation skill of lighting along the following. IV. Analyzing interior space in which the natural lighting is introduced through some literature and case studies. Physics, psychology, structure, equipment, material. V. The last, the author rearranged the results of this study.

• Radiation Oncology Journal
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• v.32 no.3
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• pp.208-212
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• 2014

Marfan syndrome is one of the collagen vascular diseases that theoretically predisposes patients to excessive radiation-induced fibrosis yet there is minimal published literature regarding this clinical scenario. We present a patient with a history of Marfan syndrome requiring radiation for a diagnosis of a right brachial plexus malignant nerve sheath tumor. It has been suggested that plasma transforming growth factor beta 1 (TGF-${\beta}1$) can be monitored as a predictor of subsequent fibrosis in this population of high risk patients. We therefore monitored the patient's TGF-${\beta}1$ level during and after treatment. Despite maintaining stable levels of plasma TGF-${\beta}1$, our patient still developed extensive fibrosis resulting in impaired range of motion. Our case reports presents a review of the literature of patients with Marfan syndrome requiring radiation therapy and the limitations of serum markers on predicting long-term toxicity.

• The Research Journal of the Costume Culture
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• v.12 no.6 s.53
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• pp.897-907
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• 2004

The aim of this study is provide fundamental data on the glove size and pattern-making. The study was conducted targeting 60 men and 271 women whose age were within the limits 18-35 in Seoul and the neighboring districts. A total of 90 features in the right hand wew used for the anthropometric measurement and analysis using anthropometry and photometry. The result show that there was a difference between men and women' hand. And the result of correlation analysis between hand factors, length factor related to length and depth factors, breadth factor related to breadth and circumference factors. The sailing glove size in Korea was not suitable to Index finger circumference at 1st Phalanx and Middle finger length.

• ETRI Journal
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• v.20 no.1
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• pp.96-112
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• 1998

The patentability of computer program has been discussed because of its deviation from the traditional definition of a patent. The relativities of computer programs to hardware are classified to measure the relative patentability of computer programs in this paper. It can be seen through the patentability analysis that the change in patentability basically follows an exponent part of the function is a damping factor that determines a patentability degree or trend. The basic patentability of computer programs is revealed when the damping factor value is 1, and a statistical patent specification, an appropriate expression of applicability and substantiality of computer programs is needed to acquire a patent right.

• Korean Journal of Acupuncture
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• v.20 no.2
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• pp.21-29
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• 2003

Objectives : Assuming that the characteristic of meridian system has been similar to that of electrical potentials in human body and that measurements of electrical potential at well(井穴) and sea (合穴) points in branches of the twelve meridians(WSBTM) will be representative of measurements of the twelve meridians, to measure the electrical potentials of 13 patients with stiffness of nape(項强症, SN), to find out the characteristic of meridian system in patients with SN. Methods : Electrical potentials of well and sea points in the meridians in 13 patients with stiffness at neck diagnosed as SN were repeatedly measured by physiograph(PowerLab). Measurements of those electrical potentials were analyzed by factor analysis. Results and Conclusions : The electrical potentials of WSBTM at the left side were divided into five factors. On the other hand those at the right side were divided into five factors. In conclusion, electrical potentials of well and sea points might be the representative meridian to show their characteristics.

• 전기의세계
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• v.18 no.2
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• pp.7-14
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• 1969

From the first customer located right at the substation to the last customer at the end of the line, voltage must be held within close limits, so the voltage regulation is more important than the thermal limit. On a typical distribution system during the peak load period, the voltage drop may be serious enough to cause unsatisfactory operation of home appliances in the residential area, and present many problems to manufacturing industries, where the voltage must be maintained within close limits to insure smooth operation. Among all the factors contributing to voltage drop in the distribution system, the voltage drop in the distribution transformer may account for 30% of this figure. If we can eliminate this factor, the power companies can provide better quality electricity to more customers with the existing distribution facilities, thus saving on initial investment costs. Taking all these problems into consideration, the author undertook the design of a capacitive transformer which would give zero voltage drop at rated load and at 80% lagging power factor while incorporating overload features to withstand 400% overload for at least 100 seconds. The following are the results obtained through design, manufacture and test of an initial experimental transformer built with these specific purposes.