• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.5
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• pp.657-665
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• 2003

Several interesting results were obtained from the flow visualization experiment in the accompanying paper, Part I. in the present study, Part II, a numerical study has been carried out to explain the detailed flow phenomena in micro-channel filling process. Hele-Shaw flow approximation was applied to the micro-channel geometry based on the small characteristic length. And surface tension effect has been introduced on the flow front as the boundary condition with the help of a dynamic contact angle concept between the melt front and the wall. A dimensional analysis for numerical results was carried out and a strong relationship between dimensionless pressure and Capillary number is obtained. The numerical analysis results are compared with the flow visualization experimental observations. And the numerical system developed in the present study seems to be able to predict the interesting micro-channel filling flow characteristics observed from experiments.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.1-14
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• 2008

This study was to describe the ecological survey of wetland plants from Sinbul Mt. and suggest the ways of the sustainable ecological management and wise use. We found 167 plant species. Molinia japonica HACK was the most dominant species and Asarum maculatum NAKAI, Drosera rotundifolia L. and Utricularia racemosa WALL were considered as the most important species. Thus, it was concluded that this area need strong conservation due to the necessity for species diversity. Such several management schemes as the designation for national wetland conservation area, continuous monitoring, cautious surveillance and wise management were suggested to implement successful conservation.

• Journal of Korean Neurosurgical Society
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• v.52 no.3
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• pp.250-253
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• 2012

We report a rare case of cerebellar liponeurocytoma with an unusually aggressive histopathology. A 49-year-old man presented with a four-month history of headache, vertigo, and progressive swaying gait. Magnetic resonance imaging showed a $3{\times}3.5cm$ sized relatively well-demarcated round mass lesion in the fourth ventricle, characterized by high signal intensity on T2-weighted images. Postcontrast images revealed strong enhancement of the solid portion and the cyst wall. The patient underwent suboccipital craniectomy and tumor removal. The pathologic diagnosis was cerebellar liponeurocytoma. Adjuvant radiotherapy was offered due to concerns related to the high proliferative index (Ki-67, 13.68%) of the tumor. At the last routine postoperative follow-up visit (12 months), the patient complained of no specific symptom and there was no evidence of tumor recurrence. However, longterm follow-up and the analysis of similar cases are necessary because of the low number of reports and the short follow-up of cases.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.219-222
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• 2005

Recently, the interest of the engine capacity and environment of the atmosphere is increasing, so the researches for the engine capacity have been conducted for a long time. But the internal environment of an automotive engine is very severe. A piston is exposed to combustion gas of over $2000^{\circ}C$ and strong friction is occurred by high speed motion in the cylinder. The fraction between piston and wall of the cylinder causes the increase of temperature in the engine. The temperature of the engine has an effect on the engine capacity. If the temperature is high, the capacity of the engine is low. So we have to maintain the optimum temperature. To maintain the optimum temperature, the enough flow rate of the engine oil is needed. The oil jet is used to control the flow rate of the engine oil and supply the engine oil to the piston and cylinder. The purpose of this study is to check the mass flow rate of the engine oil and the characteristics of internal flow of the oil jet. Flow pattern of the engine oil is very important because it concludes the loss in the oil jet. This study is the previous research about the oil jet and we will consider the movement of the ball check valve to get more accuracy result.

• Korean Institute of Interior Design Journal
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• v.27 no.1
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• pp.48-57
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• 2018

Recently, cosmetic shops are facing a complicate economy situation and a great number of brands are attempting two-way communication with customers, not one-way communication. 'Brand' equity is important to deliver virtual brand mark as visual image. We have 4 steps for brand identity structure, and this study is about the first 'brand-awareness' and the second step 'brand-image'. We investigated the correlation between brand-awareness and brand-image after searching which spatial elements are highly effective to both steps as we designated 5 cosmetic shops. We already organized the means of spatial analysis and we separated into two elements, constructive and decorative. For constructive element, a shop needs a distinct ceiling and wall design, and for decorative element, strong brand image communication is required through showcase design. We proved that brand awareness and brand image have the correlation, which also can be in direct proportion, by regression analysis. The result of this study shows that improving brand awareness as the primary element for cosmetic road shop can be an effective way to enhance brand image.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.12
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• pp.3287-3296
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• 1994

For the numerical computation of three-dimensional compressible flow field within a blade row in a centrifugal compressor, a quasi 3-dimensional solver which combines a reversible B-B flow and an irreversible H-S flow using finite element methods was developed. In a reversible B-B flow, the governing coordinates are modified in order to be applied to any type of turbomachinery, and two kinds of stream functions are introduced in order to make the Kutta condition exactly satisfied. In an irreversible H-S flow, the changes of entropy in the irreversible governing equations are determined not by empirical source but by the theoretical treatment of dissipation forces. The dissipation forces are obtained from the distribution of shear stresses in the flow passage which are given from the wall shear stresses using the exponential functions. A more accurate quasi-3-dimensional solver is established where the effect of body forces is involved in the non-axisymmetric H-S flow. Some numerical results obtained from authors' previous studies for axial flow machines assure that the present method is able to predict well as long as the flow is subsonic and not under strong viscous effect.

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.171-177
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• 2013

Efficient extraction of total proteins from soil microorganisms is tedious because of small quantity. In this regard, an improved method for extraction of whole cell proteins is developed from soil microorganisms, Saccharomyces cerevisiae and Pichia pastoris. of which the cell wall are very strong. Pretreatment with NH4OH prior to the final extraction using NaOH/SDS was tried under the basis that ammonium ion was possible to enhance the permeability and/or to weaken the yeast cell walls. The pre-treatment of yeast cells with NH4OH drastically enhanced the protein extraction when it was compared with control (without NH4OH pre-treatment). At the pre-treatment of 0.04 N NH4OH at pH 9.0, about 3 fold of proteins was obtained from p. pastoris. Ammonium hydroxide appears to penetrate into the yeast cell walls more readily at basic pH. The effect of NH4OH pretreatment was pH dependent. The methods developed in this experiment might be applicable for an effective extraction of yeast proteins for the purpose of biochemical studies, especially proteomic analysis.

• Korean Institute of Interior Design Journal
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• no.13
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• pp.231-237
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• 1997

One of the clearest reactions against Modern architecture, and its planning ideology of comprechensive development, was the neo-Regional movement which arose at more or less the same time in serval countries. In the mid-fifties architects in Mexico started to design architectures which mixed vermacular and Modern methodology to recall traditional buildings. This popular alternative to Modernism had caught on in Mexico by the recent to become the accepted approach for the most regional building built by the Mexican architects. The regional architecture provided the continual activity, safety and economy of traditional life which was lacking in so many Modern building, while the these ages provided a cultural continuity. Anonymity of craftsmanship, but personalization of each building; enclosed wall of strong color, wide inward opening, but flat roof; emotional layouts and poetic outdoor water space, but variable massing; as it the buildings had been constructed over several years-these were the contradictory signs of neo-Regionalism. The Regional architecture has direct reference to human inhabitation and use, and it embraces mystery, poetic sense, a quality we are losing in Modern life. There is a freedom from rules, which shows up especially in an insouciant use of color, just for fuv.

• Structural Engineering and Mechanics
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• v.40 no.4
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• pp.517-539
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• 2011

This paper presents the seismic responses of a 1:5-scale five-story reinforced concrete building model, which represents a residential apartment building that has a high irregularity of weak story, soft story, and torsion simultaneously at the ground story. The model was subjected to a series of uni- and bi-directional earthquake simulation tests. Analysis of the test results leads to the following conclusions: (1) The model survived the table excitations simulating the design earthquake with the PGA of 0.187 g without any significant damages, though it was not designed against earthquakes; (2) The fundamental mode was the torsion mode. The second and third orthogonal translational modes acted independently while the torsion mode showed a strong correlation with the predominant translational mode; (3) After a significant excursion into inelastic behavior, this correlation disappeared and the maximum torsion and torsion deformation remained almost constant regardless of the intensity of the two orthogonal excitations; And, (4) the lateral resistance and stiffness of the critical columns and wall increased or decreased significantly with the large variation of acting axial forces caused by the high bi-directional overturning moments and rocking phenomena under the bi-directional excitations.

• Structural Engineering and Mechanics
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• v.32 no.1
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• pp.95-126
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• 2009

The present contribution addresses the parallelization of advanced simulation methods for structural reliability analysis, which have recently been developed for large-scale structures with a high number of uncertain parameters. In particular, the Line Sampling method and the Subset Simulation method are considered. The proposed parallel algorithms exploit the parallelism associated with the possibility to simultaneously perform independent FE analyses. For the Line Sampling method a parallelization scheme is proposed both for the actual sampling process, and for the statistical gradient estimation method used to identify the so-called important direction of the Line Sampling scheme. Two parallelization strategies are investigated for the Subset Simulation method: the first one consists in the embarrassingly parallel advancement of distinct Markov chains; in this case the speedup is bounded by the number of chains advanced simultaneously. The second parallel Subset Simulation algorithm utilizes the concept of speculative computing. Speedup measurements in context with the FE model of a multistory building (24,000 DOFs) show the reduction of the wall-clock time to a very viable amount (<10 minutes for Line Sampling and ${\approx}$ 1 hour for Subset Simulation). The measurements, conducted on clusters of multi-core nodes, also indicate a strong sensitivity of the parallel performance to the load level of the nodes, in terms of the number of simultaneously used cores. This performance degradation is related to memory bottlenecks during the modal analysis required during each FE analysis.