• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.455-458
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• 2004

We present an efficient heuristic algorithm to reduce glitch power dissipation in combinational circuits. In this paper, the total number of glitches are reduced by replacing existing gates with functionally equivalent ones and by gate sizing which classified into three types and by buffer insertion which classified into two types. The proposed algorithm combines gate freezing, gate sizing. and buffer insertion into a single optimization process to maximize the glitch reduction. Our experimental results show an average of $67.8\%$ glitch reduction and $32.0\%$ power reduction by simultaneous gate freezing, gate sizing, and buffer insertion.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.110-116
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• 1994

In this research, the tensile strength of molded parts and pressure distribution were analyzed to study the cavity filling stage and packing stage in injection molding. The measurement of cavity pressure was obtained by a data acquisition system with the installation of transducers in the cavity. Molded parts were tested by a universal testing machine to obtain the tensile strength. For the experimental work, the tensile strength of molded parts increased with longer packing time and exact freezing time of the gate was obtained by a cavity pressure curve. In addition, the effect of packing did not occur and tensile strength was almost constant after early 1.5 sec of the freezing time of gate. Density tended to be higher about 0.2% due to a larger degree of mold temperature and melt temperature. Also, changing pressure in the cavity was effectively sensed. Thereafter, the possibility of the development of pattern recognition expert system was confirmed on the basis of the experimental results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.160-165
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• 2012

The packing, among the components comprising the gate valve, is used to sustain the air-tightness and the study on change of shape or pattern has been carried out to maximize the functions, but the study on changing the location or the size of the packing in a bid to prevent the freezing has rarely been implemented. Thus, This study is intended to evaluate the thermal strain of packing by heat transfer from territory of extremely low temperature as well as the temperature distribution to the upper part of the packing using numerical analysis method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.2
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• pp.322-329
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• 1995

Series of experimental work was performed to mold tensile specimens by using the injection molding machine Mold temperature, melt temperature and packing time were chosen as processing parameters for studying the effects of those conditions on the linear shrinkage of final product. Here, each processing variable was decided from the numerical simulation and resin manufacturer's suggested value. The effects of molding conditions on the linear shrinkage in flow direction of the resin were analyzed by measuring the parts 2, 10, 30 and 60 days after molding. As a result, the linear shrinkage increased with the higher mold and melt temperature, and the change of mold temperature has shown more influence. The linear shrinkage of polypropylene has been found to progress up to 30 day with the lapse of the time, and the amount of the linear shrinkage has shown to be between 2.14% and 2.75%. In addition, the effects of packing pressure on the weight has shown to be extremely significant up to freezing time, and proper packing time of the tensile specimen has been found to be 2.0 seconds.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1025-1028
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• 2008

Using of maintenance system for gate bridge algorism, We made out algorism and engine for prediction of life cycle by neutralization, freezing-thawing and damage from sea wind. To objective of this system, user can use easily with maintenance system for gate bridge. Also, to improve of maintenance efficiency, web-program made out by superannuated evaluation and analysis of field exposure data. To develope web-program, we framing structure design of database, which is adapted to method of maintenance, repair, and reinforcing

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.241-244
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• 2006

The basic prediction model was constructed to obtain optimal maintenance method for concrete structure under marine environment by exploring the mechanism of mono and combined deterioration in lab. This model was planned to be upgraded with data acquired from several exposure specimens under same environment as structures. The computer program developed to give useful guidance observer would be improved. Several repair materials and repair construction methods applied to exposure specimens will be tested for its performance of prohibit salt attack and freezing & thawing action during experimental period about ten years. All of these data could be available to complete the prediction system. The manager will be able to use the system for optimal maintenance of marine concrete structures.

• Korean Journal of Plant Tissue Culture
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• v.27 no.5
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• pp.415-421
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• 2000

The disaccharide trehalose ($\alpha$-D-glucopyranosyl-$\alpha$-D-glucopyranoside) is found in variety of organ-isms that are able to withstand almost complete desiccation. In order to identify the function of trehalose in plants, we isolated Arabidopsis trehalase (AtTRE) gene that encodes the enzyme able to hydrolyze trehalose to glucose, and trehalose-6-phosphate synthase isolog, TPS3 gene by RT-PCR. The AtTRE had the substrate specificity to hydrolyze only trehalose, and a broad pH range of enzyme activity. The AtTRE promoter/GUS reporter gene was expressed in cotyledons, mature leaf tissues including guard cells, and developing siliques. The GUS expression driven by AtTPS3 promoter was significant in root tissues, and the level of GUS activity was much higher than that of the pBll 21 control seedlings. The knockout of AtTPS3 gene in Arabidopsis resulted in the retarded root development, whereas the overexpression of AtTPS3 increased the root elongation in the presence of sucrose in MS medium. Possible functions of AtTRE and AtTPS3 in plant will be discussed. In addition, ectopic expression of yeast TPS1 driven by the inducible promoters in tobacco and potato conferred the plants on the drought and freezing tolerances.