• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.8
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• pp.2079-2087
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• 1993

The effects of subcooling and natural convection are studied numerically on the melting process of an initially subcooled phase-change medium filled inside a horizontal circular cylinder. It is postulated that melting continues with the tube wall kept at a constant temperature and with the unmelted solid core fixed. Primary emphasis is placed on the evolution of interface morphology, the local/overall heat transfer rate at the tube wall and at the interface, and the structure of natural convection. The numerical results are mainly presented in terms of the Rayleigh and subcooling numbers. As the degree of subcooling intensifies, the melting rate and the movement of the interface are impeded but the interfaces are of similar shape with the passage of time. The heat transfer characteristics are found to be mostly governed by the formation pattern of natural convection in the liquid phase. Good agreement with available experimental data is found.

• Computational Structural Engineering : An International Journal
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• v.2 no.1
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• pp.25-32
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• 2002

Natural draught cooling towers often develop visible crack structures as consequences of progressive damage processes over their life-time. The aim of this paper is a numerical demonstration of the progressive damage process of cooling towers, representatively for the reinforced concrete structures, in order to improve the durability and extend the life-time of structures subjected to such damage processes. For the analyses, the applied material model for reinforced concrete will be briefly introduced. An existing natural draught cooling tower with a pronounced crack structure, in which this crack structure indicates the typical damage pattern of large cooling towers will be numerically simulated. The change of dynamical behavior of the structure with regard to natural frequencies, reflecting the global damage process due to the degrading stiffness of the structure in dependence of the load type and intensity, will be presented and discussed.

• Proceedings of the Korean Society for Language and Information Conference
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• 2002.02a
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• pp.157-165
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• 2002

This paper describes our ongoing Korean-Chinese machine translation system, which is based on verb patterns. A verb pattern consists of a source language pattern part for analysis and a target language pattern part for generation. Knowledge description on lexical level makes it easy to achieve accurate analyses and natural, correct generation. These features are very important and effective in machine translation between languages with quite different linguistic structures including Korean and Chinese. We performed a preliminary evaluation of our current system and reported the result in the paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.377-383
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• 1996

Recently, a new technique called Electronic Speckle Pattern Inteferometry(ESPI) has been developed to overcome the drawbacks of existing holography. This technique enable real-time interference fringes to be displayed directly on TV monitor without recourse to any form of photographic processing. This research was carried out for the purpose of applying the vibration analysis method employing Electronic Speckle Pattern Interference technique to the vibration analysis of uniform rectangular cantilever plate, The natural vibration frequencies found by ESPI were in fair agreement with theoretical eigen frequencies acquired using theoretical formula G. B. Warburton proposed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.269-274
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• 2003

Vibration table is required to obtain high packing density in expendable pattern casting process. Packing density, which is an important manufacture factor, depends on the vibration pattern induced by vibration table. Modal test is utilized to identify the dynamic characteristics of vibration table. And finite element method is used to modify flask by fixing the stiffener. The positions of stiffener to modify are found and the natural frequency could be easily shifted to the objective value by using sensitivity analysis.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2094-2102
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• 2016

In this paper, we propose an extended Kalman filter(EKF)-based simultaneous localization and mapping(SLAM) method using laser corner pattern matching for mobile robots. SLAM is one of the most important problems of mobile robot. However, existing method has the disadvantage of increasing the computation time, depending on the number of landmarks. To improve computation time, we produce the corner pattern using classified and detected corner points. After producing the corner patterns, it is estimated that mobile robot's global position by matching them. The estimated position is used as measurement model in the EKF. To evaluated proposed method, we preformed the experiments in the indoor environments. Experimental results of proposed method are shown to maintain an accuracy and decrease the computation time.

• Journal of the Korea Furniture Society
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• v.20 no.5
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• pp.431-439
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• 2009

When we look at the pattern techniques of wooden furniture in the 19th century Joeson Dynasty, we see that furniture patterns in the main living room were showy and colorful while furniture patterns in the library room, where noble men used to study, were natural and moderate, retaining the actual color of the material without any artificial coloring. Even the serial patterns in the Hwe-Jang technique, Which were used rarely, used moderate techniques. such as weaving in patterns with colorless woods - willow and black persimmon ets. - rather than using excessive techniques. However, considering the marquetry&intarsia technique of ceramic and the silver string intarsia technique of metal then current, wood work must also have been technically advanced. Korean modern wood furniture needs remedies to improve the standard of sound wood work techniques. This study shows that pattern unit production, composition techniques, and color effects etc. Using colored patterns bars, by improving the pattern composition techniques of Marquetry&Intarsia, can be substituted for the production logic of modern manufactured furniture.

• BMB Reports
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• v.30 no.2
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• pp.119-124
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• 1997

Transforming growth $factor-{\beta}\;(TGF-{\beta})$ is a multifunctional polypeptide that exerts biological roles including cell proliferation, differentiation, extracellular matrix deposition and apoptosis in many different cell types. $TGF-{\beta}$, although known as a negative growth regulator, has not been tested in human embryo lung (HEll cells. This study attempts to understand the role of $TGF-{\beta}$ on growth control of HEL cells in relationship to tyrosine phosphorylation pattern of cellular proteins. In density-arrested HEL cells treated with $TGF-{\beta}$, analysis of Western immunoblot showed induction of tyrosine phosphorylation of two major cellular proteins (15 kDa and 45 kDa). In normal proliferating HEL cells with different concentrations of serum, further analysis indicated that the increase in tyrosine phosphorylation of a 45 kDa protein was regulated in serum concentration-dependent manner. However, in proliferating HEL cells treated with $TGF-{\beta}$, tyrosine phosphorylation of 45 kDa was down-regulated. Calcium involvement in the regulation of tyrosine phosphorylation of 45 kDa and 15 kDa proteins was also examined. Tyrosine phosphorylation of 15 kDa protein but not of 45 kDa protein was regulated by exogenous calcium. The level of tyrosine phosphorylation of 15 kDa protein was low at reduced caclium concentration and high at elevated caclium concentration. $TGF-{\beta}$ reversed the pattern of tyrosine phosphorylation of 15 kDa protein. These results suggest that tyrosine phosphorylation of 45 and 15 kDa proteins in HEL cells may be controlled depending on the physiological status of the cells, i.e., low in arrested cells and high in proliferating cells. And the tyrosine phosphorylation of the two proteins appears to be down- or up-regulated by $TGF-{\beta}$.

• The Korean Journal of Ecology
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• v.7 no.4
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• pp.232-238
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• 1984

The author hatched the eggs of Korean frog, Rana nigromaculata in natural water, and reared the tadpoles in natural water as control group and in seven copper ion groups contaminated by 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, and 1.0 ppm of copper ion. The influences of copper ion on the growth of the tadpoles were analyzed, and the results were summarized as follows: 1) The copper ion inhibited the growth of the tadpole. 2) The tadpoles were not survived for 20 days in the copper ion of 0.4~0.5ppm, and in the 0.7ppm, the tadpoles were not survived for 1 day after hatch. 3) The critical lethal concentration of Korean tadpole is regarded as 0.6ppm of copper ion. 4) The growth of head with and body length show a convexin increase pattern. 5) In the growth quantity of head width and body length, that of natural water shows the most rapid increase pattern, and that of the copper ion groups 0.1, 0.2, and 0.3ppm follows in that order. 6) The coefficient of relative growth($\alpha$) of control group is the greatest value, and that of the copper ion groups of 0.1, 0.2, and 0.3ppm follows in that order. The natural water shows the positive allometry, the contaminated groups shows the negative allometry in the relative growth of the contaminated groups to the natural water. 7) Body length shows positive allometry in the relative growth to head width.

• Smart Structures and Systems
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• v.26 no.3
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• pp.291-309
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• 2020

To study oceanic and meteorological problems related to climate change, Korea has been operating several ocean research stations (ORSs). In 2011, the Gageocho ORS was attacked by Typhoon Muifa, and its structural members and several observation devices were severely damaged. After this event, the Gageocho ORS was rehabilitated with 5 m height to account for 100-yr extreme wave height, and the vibration measurement system was equipped to monitor the structural vibrational characteristics including natural frequencies and modal damping ratios. In this study, a mass reallocation method is presented for structural model updating of the Gageocho ORS based on the experimentally identified natural frequencies. A preliminary finite element (FE) model was constructed based on design drawings, and several of the candidate baseline FE models were manually built, taking into account the different structural conditions such as corroded thickness. Among these candidate baseline FE models, the most reasonable baseline FE model was selected by comparing the differences between the identified and calculated natural frequencies; the most suitable baseline FE model was updated based on the identified modal properties, and by using the pattern search method, which is one of direct search optimization methods. The mass reallocation method is newly proposed as a means to determine the equivalent mass quantities along the height and in a floor. It was found that the natural frequencies calculated based on the updated FE model was very close to the identified natural frequencies. In conclusion, it is expected that these results, which were obtained by updating a baseline FE model, can be useful for establishing the reference database for jacket-type offshore structures, and assessing the structural integrity of the Gageocho ORS.