• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.8
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• pp.831-838
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• 2011

A growing bubble can be squeezed for water, and it will then encounter flow instability, which reverses toward upstream in straight micro-channels. To reduce the flow instability, a micro-channel that expands at the downstream end has been found to be effective. In the expanding area, a growing bubble will tend to move downstream because the net surface tension force of a vapor-liquid interface is inversely proportional to the local radius of curvature. We propose a static flow instability model and validate it experimentally. Moreover, we apply the local-instability parameter concept to the real design of a stable evaporative micro-channel with an expanding area. Based on the localinstability model, we establish a static design for stable expanding evaporative micro-channels.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.7
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• pp.303-308
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• 2001

This paper presents algorithm to plan construction and expanding of substation considering contingency accidents by proposing utilization factor according to configuration of substation bank system. In this paper, firstly, proper sphere of supply area by each district which could be standardized with respect to its supply capacity is established under assumption of long term load forecasting. Secondly, goal of utilization ratio based on configuration of substation bank was set to keep reliability by remaining sound bank when it happen to one bank accidents. Finally, it is set up for optimal construction and expanding of substation considering economy and reliability simultaneously about substation to exceed these ratio. To verify proposed algorithm, at first, after adopting a part of Kangnam area in Seoul as area for testing, it is divided into several regions for this area according to power branches of power utility. Secondly, by deriving correlation factor between load demand and economic indicators in these region respectively, the regional load forecasting was performed with economic growth and city plan scenario. Finally, based on the predicted load demand by region and land use data which is identified from air-photographic, the load demand by district was predicted. Also, planning for substation considering contingency is formulated to expand taking into account computing utilization factor which is based on configuration of substation bank respectively.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.1
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• pp.175-182
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• 2005

A laser beam expanding technique is employed to fabricate precise nano-patterns in a nano-replication printing (nRP) process. In the nRP process, some patterns can be fabricated in the range of several microns inside on a polymerizable resin by using a volume-pixel (voxel) matrix that is transformed from a two-tone bitmap figure file. The liquid monomers are polymerized by means of a two-photon-absorption (TPA) phenomenon that is induced by a femtosecond (fs)-pulse laser. The yokels are generated consecutively to merge into adjoining yokels in the process of fabricating a pattern. The resolution of a fabricated pattern can be obtained under the diffraction limit of a laser beam by the two-photon absorbed polymerization (TPP). In this work, a beam-expanding technique has been applied to enlarge a working area and to fabricate precise patterns. Through this work, a working area is expanded by the technique as much as 2.5 times compared with a case of without a beam expanding technique, and precision of outside patterns is improved.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.67-74
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• 2001

Now that importance of landscape planning unique to each area is emphasized, it is necessary to conduct landscape planning by taking advantage of natural environments unique to each ares, because its natural environments are regarded as one of the assets the area possesses. This study targets at Kawachinagano City, Osaka, one of the residential areas that I not only rich in natural and historical elements, but also has been rapidly growing. The purposes of this study are to evaluate change in landscape structure over time by analyzing relation between landform and pattern of expanding the built-up area at three time points of 1932, 1967, and 1994 with GIS (ARC/INFO 7.0.3, ARC/View 3.0 (ESRI)), as well as to make some suggestions for planning landscape unique to the area. Data on main ridges, sub ridges, main rivers, and other landform were read from the elevation map, and data on woodland, and parks and open spaces (having more than 3 ha area) were read from the existing land use map. The data were used to understand the natural structure of the city from topographic viewpoint. Next, the existing land use map prepared with data on the built-up area and urban axes consisting of roads and streets were overlaid on the elevation map in order to understand relation between pattern of expanding the built-up area and the natural structure.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.339-343
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• 1999

A strain of gas-producing and volume-expanding yeast was isolated from Gochujang made in Sunchang by the traditional ways and was identified to be a Saccharomyces sp. This yeast was detected only in malt among the several ingrediants of Gochujang which means that the volume-expanding yeast comes into Gochujang at the time of making products through malt one of the major ingredients. However boiling of the malt-saccharified rice could not prevent the occurrence of the volume-expanding yeast in Gochuj-ang. This yeast was contained in the range of 5.67∼7.75 log10CFU/g in products made and aged between 1 monty and 3 year in Sunchang area.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.112.2-112.2
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• 2011

We carry out a systematic study of HI shells and supershells in the first Galactic quadrant (l = $32^{\circ}$ to $77^{\circ}$, b = $-10^{\circ}$ to $10^{\circ}$) using the "Inner-Galaxy Arecibo L-band Feed Array (I-GALFA)" HI 21-cm survey data. The high-resolution (3.'4) and high sensitivity (0.2 K) of the survey provide us an opportunity to exploit the true nature of the sources detected in previous low-resolution studies and also to detect faint and/or small shells that were not detectable before. Our work is composed of three parts: (1) confirm the objects in the low-resolution (about 30') catalog of Heiles (1979), (2) search for fast-expanding HI shells associated with Galactic supernova remnants (SNRs), and (3) search for new shell structures. Among the 21 Heiles' supershells in the I-GALFA survey area, we confirm fourteen. The high resolution data reveal their complex morphology, and provide direct evidence for expansion in some sources. Among the 39 Galactic SNRs in the survey area, we find five with associated fast expanding HI shells, which is consistent with previous results. A remarkable result from the SNR study is the detection of HI gas at very high negative velocities in the SNR W44 that should be from the approaching part of the HI expanding shell. This is the first time to detect both the approaching and receding sides of an expanding shell in HI 21-cm emission line in SNRs. We have found 33 new shell candidates of angular sizes ranging from 0.5 to 6.5 degrees, half of which appear to be expanding. We summarize these results and discuss some individual interesting objects in detail.

• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.409-414
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• 2018

Extrapolating the correction information of ionosphere is essential for expanding wide area differential GPS (WADGPS) service area beyond the reference station network. In this paper, design and analysis of the artificial neural network for expanding the ionospheric correction region will be proposed. First, analysis about influence of each input of neural network were performed. The inputs are the day/year periodic function, sunspot number, and geomagnetic index (Ap). Second, performance analysis with respect to the number of hidden layers and neurons in the neural network is shown. As a result, estimation of total electron contents (TEC) on the high/low latitude regions in solar max(2014) are displayed.

• Journal of Family Resource Management and Policy Review
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• v.1 no.1
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• pp.101-115
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• 1997

This study was designed to examine the socialization of household work utilizing ecological theory. The main purposes were to identify the socialization level, and to predict the socialization of household work in term of the selected variables. The sample was drawn from housewives of expanding stage of family life cycle in Seoul. 518 respondents were analyzed using SPSS/PC+ statistical package. The results of this study were as follows: 1. Among the variables of food area, education of housewife, type of housing, family income, number of children had significant influence. 2. Among the variables of clothing area, family income was the only important variable. 3. Among the variable of housing area, number of household equipment, number of aids for household work, education of housewife, family income, attitude of housewife’s role, number of aids for household work had significant influence. 4. Among the varables of home management area, number of household equipment, family income, self control had significant influence. 5. Among the environment variables of household work, social-cultural environment had the most important effect on the socialization of household work.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.552-554
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• 2000

This paper presents algorithm to plan construction and expanding of substation considering contingency accidents by proposing utilization factor according to configuration of bank system. In this paper, at first, proper sphere of supply area in each district which could be standardized with respect to its supply capacity is established under assumption which was made long term load forecasting in district respectively. Secondly, goal of utilization ratio according to configuration of substation bank was set to keep reliability by remaining sound bank when it happen to one bank accidents Finally, optimal construction and expanding of substation considering economy and reliability simultaneously about substation to exceed these ratio could be anticipated.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.92-94
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• 2000

This paper presents algorithm to plan construction and expanding of substation considering contingency accidents by proposing utilization factor according to configuration of substation bank system. In this paper, above all, proper sphere of supply area by each district which could be standardized with respect to its supply capacity is established under assumption of long term load forecasting which was made by district respectively, and then goal of utilization ratio based on configuration of substation bank was set to keep reliability by remaining sound bank when it happen to one bank accidents. Finally it is set up for optimal construction and expanding of substation considering economy and reliability simultaneously about substation to exceed these ratio.