• Journal of Families and Better Life
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• v.22 no.6 s.72
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• pp.89-97
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• 2004

The purpose of this study was to investigate the characteristics of leisure facilities and to examine residents' needs for leisure facilities in apartment complex. The questionnaire survey and content analysis were used. The Data for content analysis were 476 site plans, and the subjects of questionnaire survey were 673 residents lilving in 35 apartment complex. Frequency, Percentage, and mean, ANOVA-A, x^{2}-test, and multiple regression were used for data analysis. The major results were as follows. 1) Facilities for children play, and senior, sports facilities, community center, green area, and resting place were included in leisure facilities in apartment complex. These facilities were different according to complex site and built-period. 2)The degree of satisfaction of leisure facilities was lower than neutral. The satisfaction of leisure facilities related with diversity of leisure facilities and program, and poor environment. 3) Subjects needed the facilities recommended in housing act including diverse leisure facilities such as sports center and resident's self government facilities. And they needed divers facilities for sports. 4) In terms of location, they needed leisure facilities which was closer to their house.

• Fibers and Polymers
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• v.6 no.1
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• pp.55-65
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• 2005

Extensible elastica solutions of two-dimensional deflection of crimped fiber cantilever of circular wavy crimp were obtained for one end clamped boundary under concentrated, inclined and dead tip load Fiber was also regarded as a linear elastic material. Crimp was described as a combination of semicircular arcs smoothly connected with each other having con­stant curvature of all the same magnitude and alternative sign. Also the inclined load direction was taken into account. The solutions were expressed as the recursive forms of integrals in two different cases, which can also be transformed to elliptic integrals respectively. Comparing the data with inextensible ones was carried out. Consequently in the solution, the normal strain of neutral axis is expressed in terms of cross-sectional area, second moment of area and normalized load parameter. Examples of the circular cross-sectioned fiber are presented. As a result, the differences of normalized load between inexten­sible and extensible elastica solutions when the radius ratio becomes 0.1 were maximum $\Lambda$ = 0.1.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E3
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• pp.153-163
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• 2002

A laboratory- scale dual-column biofilter system was used to study the biofiltration of dimethyl disulfide (DMDS). The gas flow rate and DMDS concentration to the biofilter were varied to study their effect on the remov-al of dimethyl disulfide. Operating parameters such as pH, temperature, and water content were monitored during the biofilter operation and necessary precautions were taken to keep these parameters within the acceptable limits. It was observed that the removal efficiency of DMDS was optimal at neutral pH values. After five month op-eration, the neutralization of the filter beds with sodium carbonate became necessary for the optimum operation of the biofilters. The microbial population already present in the compost mixtures was found to be adequate in treat-ing DMDS. The compost mixtures were found to be similar in terms of biofiltration efficiency of DMDS. However, pressure drops observed in the first column compost mixture (compost/ peat mulch) was extremely high, making this compost economically not feasible. The second mixture (compost/bark) provided pressure drops within accept-able limits. A minimum residence time of 30 seconds at the optimal operating conditions appeared to be adequate for achieving high removal efficiencies (>90%).

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.4
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• pp.451-462
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• 2016

Photovoltaic energy conversion becomes main focus of many researches due to its promising potential as source for future electricity and has many advantages than the other alternative energy sources like wind, solar, ocean, biomass, geothermal etc. In Photovoltaic power generation multilevel inverters play a vital role in power conversion. The three different topologies, diode-clamped (neutral-point clamped) inverter, capacitor-clamped (flying capacitor) inverter and cascaded h-bridge multilevel inverter are widely used in these multilevel inverters. Among the three topologies, cascaded h-bridge multilevel inverter is more suitable for photovoltaic applications since each pv array can act as a separate dc source for each h-bridge module. This paper presents a single phase Cascaded H-bridge five level inverter for grid-connected photovoltaic application using sinusoidal pulse width modulation technique. This inverter output voltage waveform reduces the harmonics in the generated current and the filtering effort at the input. The control strategy allows the independent control of each dc-link voltages and tracks the maximum power point of PV strings. This topology can inject to the grid sinusoidal input currents with unity power factor and achieves low harmonic distortion. A PID control algorithm is implemented in Arm Processor LPC2148. The validity of the proposed inverter is verified through simulation and is implemented in a single phase 100W prototype. The results of hardware are compared with simulation results. The proposed system offers improved performance over conventional three level inverter in terms of THD.

• Speech Sciences
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• v.12 no.4
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• pp.113-128
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• 2005

The underlying premise of this study was that L1 production is easily transferred into L2 production. In neutral intonation, there is a consonant-tone correlation in Korean: High tone patterns are correlated with voiceless aspirated and tense consonants and Low-High tone patterns are correlated with lax or other voiced consonants. The purpose of this study was to see whether the correlation in Korean (L1) is transferred into English (L2) production and whether the degree of transfer differs depending on the degree of proficiency. Eight Korean speakers and two American speakers participated in the experiment. F0 contours of words and sentences were collected and analyzed. The results of the present study showed that there is a strong correlation between voicing and tone in L2 utterances. When utterance-initial consonant types were voiceless, the word or the sentence began with the H pattern; otherwise it had the LH pattern. The degree of interference differed depending on the degree of proficiency: less proficient speakers showed a stronger correlation in terms of the magnitude (Hz) and size (ms) of the effects on F0. The results indicate that the consonant-tone correlation in L1 is strongly transferred into L2 production and the correlation transfer can be one of the actual aspects that cause L2 speakers to produce deviant L2 accents and intonation.

• Journal of the Korean housing association
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• v.17 no.6
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• pp.159-168
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• 2006

The purpose of this study was to analyze the preference and needs of leisure facilities of residents living in apartment complexes. The questionnaire survey was conducted in the selected apartment complexes, and 676 responses were used for data analysis. The statistical techniques used for data analysis included frequencies, percentage, mean, $X^2$-test, and multiple regression. The major findings were as follows: 1) Subjects needed the diverse leisure facilities such as sports center and resident's self government facilities. And they needed diverse facilities for sports. 2) In terms of location, they needed leisure facilities which was closer to their house. 3) The degree of satisfaction of leisure facilities was lower than neutral. The satisfaction of leisure facilities related with diversity of leisure facilities and program, and poor environment. 4) It was found that the respondents preferred safe and various leisure facilities, and the leisure facilities were exclusively used for the residents only, and the use by non-residents should be charged at the expense. Also, respondents were willing to pay additional fee for the better quality of leisure facilities, and sports leisure facilities congregated in one building were highly desirable.

• Journal of Power Electronics
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• v.13 no.1
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• pp.70-76
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• 2013

For high power high step-down dc-dc conversion applications, conventional three-level dc-dc converters are subject to extreme duty cycles or increased volume and cost due to the use of transformers. In this paper, a transformerless three-level dc-dc buck converter with a high step-down conversion ratio is proposed. The converter comprises two asymmetrical half bridges, which are of the neutral point clamped structures. Therefore, the output pulse voltage of the converter can be obtained in terms of the voltage difference between the two half bridges. In order to realize harmonious switching of the converter, a modulation strategy with capacitor voltages self balance is presented. According to the deduced output dc voltage function, transformerless operation without extreme duty cycles can be implemented. Experimental results from a 1kW prototype verify the validity of the proposed converter. It is suitable for ship electric power distribution systems.

• Proceedings of the KIPE Conference
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• 2013.07a
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• pp.244-245
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• 2013

This paper proposes a control algorithm for permanent magnet synchronous generator with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage offshore wind power system under unbalanced grid conditions. The proposed control algorithm particularly compensates for the unbalanced grid voltage at the point of common coupling in a collector bus of offshore wind power system. This control algorithm has been formulated based on the symmetrical components in positive and negative rotating synchronous reference frames under generalized unbalanced operating conditions. Instantaneous active and reactive power are described in terms of symmetrical components of measured grid input voltages and currents. Negative sequential component of ac input current is injected to the point of common coupling in the proposed control strategy. The amplitude of negative sequential component is calculated to minimize the negative sequential component of grid voltage under the limitation of current capability in a voltage source converter. The proposed control algorithm makes it possible to provide a balanced voltage at the point of common coupling resulting in the generated power of high quality from offshore wind power system under unbalanced network conditions.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.43-58
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• 2005

The objective of the study is to understand the characteristics of modernistic spatial design and, based on the understanding, to interpret fashion in terms of its spatial relationship with society, culture and human body, thereby looking into unique spatial characteristics fashion has. The main results of this study include : First, the rational space emphasizes geometric symmetry and harmony among each of design elements and is expressed by pursuing a perfect formative beauty that indicates an eternal formal beauty of a physical space. In addition, functional beauty is also pursued, making clothing convenient for activities. Second, the abstract space is characterized as a kind of purity by emphasizing simple patterns and colors and materials of purity for clothing, and it is sometimes expressed as being extremely abstract so that human body can be shown to be distorted. Third, for the uniform and neutral space, mass-production and production at home was made possible with clothing of simple patterns and of standard. In addition, it showed a tendency to become blurred in gender distinction for clothing with women wearing men's clothing, or borrowing design elements from men's clothing. Forth, the space as means of domination and control was shown to be segmented based on place, function and purpose. In addition, control on physical beauty was shown by promoting slim figures that are suited for lineal silhouette of clothing and circumstantial restriction on clothing occurred during war, serving to limit the styles of and purchase of clothing.

• Fashion & Textile Research Journal
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• v.3 no.3
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• pp.265-270
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• 2001

Korea and Japan, neighboring two nations, have similar cultural background and complicated relations in terms of their culture and constitution. In this study, clothing microclimate and subjective sensation of Korean and Japanese subjects for Hanbok, traditional costumes of Korea, were assessed and investigated differences between them. The results of the study were as follows. For Hanbok, the temperature within clothing at the chest have significant correlations with the variables of race and elapsed time with p<0.001. At the thigh, correlations with elapsed time were significant (p<0.001). For the humidity within clothing at the chest of Hanbok, correlations with variables of race were significant (p<0.001). At the thigh, correlations with race and elapsed time were significant(p<0.001). For Hanbok, Korean group reported 'slightly warm' whereas Japanese group reported 'hot' in the thermal sensation. For the humid sensation, Korean group reported 'neutral' and Japanese group reported 'humid'. For the comfort sensation, Korean group reported 'slightly uncomfortable' and Japanese group reported 'uncomfortable'. Japanese group reported high relation with comfort sensation and humidity of microclimate.