• Journal of Broadcast Engineering
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• v.16 no.5
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• pp.883-893
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• 2011

In this paper, we propose a novel focus measure that determines in-focus and out-of-focus region in an image. In addition, we achieved extended depth of field by blending the acquired image and Wiener filtered image using a decision map based on the designed focus measure. Since conventional focus measures are based on the amount of high frequency components in an acquired image, the measures may not be accurate if there exist high frequency components in out-of-focused region. To overcome the problem, we designed the novel focus measure based on effective band pass filtering. In simulations and experiments, the proposed method showed better performance than existing methods.

• Nuclear Engineering and Technology
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• v.34 no.5
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• pp.482-493
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• 2002

The MOX fuel for LWR is fabricated either by direct mechanical blending of UO$_2$ and PuO$_2$ or by two stage mixing. Hence Pu-rich particles, whose Pu concentrations are higher than pellet average one and whose size distribution depends on a specific fabrication method, are inevitably dispersed in MOX pellet. Due to the inhomogeneous microstructure of MOX fuel, the thermal conductivity of LWR MOX fuel scatters from 80 to 100 % of UO$_2$ fuel. This paper describes a mechanistic thermal conductivity model for MOX fuel by considering this inhomogeneous microstructure and presents an explanation for the wide scattering of measured MOX fuel＇s thermal conductivity. The developed model has been incorporated into a KAERI＇s fuel performance code, COSMOS, and then evaluated using the measured in-pile data for MOX fuel. The database used for verification consists of homogeneous MOX fuel at beginning-of-life and inhomogeneous MOX fuel at high turnup. The COSMOS code predicts the thermal behavior of MOX fuel well except for the irradiation test accompanying substantial fission gas release. The over-prediction with substantial fission gas release seems to suggest the need for the introduction of a recovery factor to a term that considers the burnup effect on thermal conductivity.

• Journal of Korean Society for Quality Management
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• v.40 no.3
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• pp.347-358
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• 2012

Purpose: Given the mixture components - process variables experimental data, we propose the strategy to find the proper combined model. Methods: Process variables are factors in an experiment that are not mixture components but could affect the blending properties of the mixture ingredients. For example, the effectiveness of an etching solution which is measured as an etch rate is not only a function of the proportions of the three acids that are combined to form the mixture, but also depends on the temperature of the solution and the agitation rate. Efficient designs for the mixture components - process variables experiments depend on the mixture components - process variables model which is called a combined model. We often use the product model between the canonical polynomial model for the mixture and process variables model as a combined model. Results: First we choose the reasonable starting models among the class of admissible product models and practical combined models suggested by Lim(2011) based on the model selection criteria and then, search for candidate models which are subset models of the starting model by the sequential variables selection method or all possible regressions procedure. Conclusion: Good candidate models are screened by the evaluation of model selection criteria and checking the residual plots for the validity of the model assumption. The strategy to find the proper combined model is illustrated with examples in this paper.

• Journal of Welding and Joining
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• v.32 no.5
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• pp.65-71
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• 2014

Atmospheric plasma spraying (APS) is world-widely used process in the automotive industry as a method to provide wear resistance coatings for engine cylinder bore, using various materials. The weight of engine blocks can be considerably decreased by removing cast iron liners, which can finally result in the improvement of fuel efficiency. In this study, five kinds of powder materials, 1.2C steel powder and 1.2C steel powder mixed with 5, 10, 15, 20 wt.%. molybdenum powder, were deposited by atmospheric plasma spraying in order to investigate the effect of molybdenum on the wear resistance of coatings. Microstructural analysis showed that molybdenum splats were well distributed in 1.2C steel matrix with intimate bonding. The molybdenum added coatings showed better tribological properties than 1.2C steel coating. However, above the 15 wt.%. blending fraction, wear resistance was somewhat degraded with poor roughness of worn surface due to the brittle fracture occurred in molybdenum splats. Consequently, compared to conventional liner material, gray cast iron, 10 wt. pct. molybdenum blended 1.2C steel coating showed much better tribological properties and therefore it looks very feasible to replace gray cast iron liner.

• Polymer(Korea)
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• v.27 no.5
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• pp.405-412
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• 2003

Poly(vinyl alcohol) (PVA) and N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC), a water soluble chitosan derivative synthesized by the reaction of quaternary ammonium compound with chitosan, were blended using water as a solvent and the PVA/HTCC blend films with various compositions were prepared by solution casting method. The miscibility between the two polymers and the thermal properties of the blend films were investigated using FT-IR, DSC, DMA, and TGA. Single glass transition temperatures and single melting temperatures of the blend films along with the strong and clear film state for the whole composition of blending ratios suggest the miscibility between PVA and HTCC. The PVA/HTCC blend films with HTCC content of 1% and greater showed excellent antimicrobial activity.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.332-340
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• 2008

Two component polyurethane (PU) flame retardant coatings were prepared by blending trichloro modified polyesters (TCMPs) and isophorone diisocyanate isocyanurate. TCMPs were synthesized by polycondensation of trichlorobenzoic acid (TCBA), a flame retardant component, with adipic acid, 1,4 butanediol, and trimethylolpropane. The content of TCBA was varied in 10, 20, and 30 wt% for the reaction. Theses new flame retardant coatings showed various properties comparable to other non flame retardant coatings. Moreover, we carried out the combustion test and the flammability test for our flame retardant coatings. The results of vertical burning test for the coatings containing more than 20 wt% of TCBA were determined as no burn. The results of flammability test for the coatings with 20 wt% and 30 wt% of TCBA contents indicated the limiting oxygen index (LOI) values of 26% and 29% respectively, which implied relatively good flame retardancy.

• Journal of Fashion Business
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• v.3 no.3
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• pp.69-78
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• 1999

The purpose of this thesis is to investigate of fabric characteristics in women's wear as reviewing the fabric trends in 1990's domestic fashion. As a method to accomplish this research, I have examined the articles related to fashion fabric and fashion trend magerzines. This study considered women's wear relatively used diverse fabrics, there was not previous study regarding the fabrics used in domestic, since the 1990's. The social fators for the 1990's fashion were the influence of the informed, the increased concern for the ecological environment, the sattlement of young popular culture, the increase of resonable consume and social anxiety. To understand the fashion trends of the 1990's women's wear, it is divided three periods. The traditional period is from 1991 to 1993, the mixed period of the naturalism and the technology is from 1994 to 1995, the retro period is from 1996 to 1999. The charateristics of the fabrics used in 1990's women's wear were the appearance of various functional fabrics, the development of new synthetic fabric with high sensitivity, the popularization of circular knit, the fabrics with a retro mood toward traditional feminine mood and the blending of fabrics. The fashion of 1990 have had the characteristics of various utilization of the materials on the base of reasonable and practical trends than the changes of design and detail.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.90-96
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• 1999

Biodegradable films were prepared by solution blending method in the weight ratio of Chitosan and Algin for the purpose of useful bioimplants. The possibility of bioimplants, which prepared from natural polymers as a skin substitute and food wrapping materials were evaluated by measuring the biodegradability. these biodegradable films were inserted in the back of rats and their biodegradability was investigated by hematological change as a function of time. Rats study showed that low-Chitosan induced increments of monocyte and basophil after 48 hours of implantation. And medium-Chitosan showed increase of lymphocyte and decreased neutrophil counts after 48 hours of implantation. Low, medium Chitosan showed high hemoglobin contents, medium and high Chitosan showed high hematocrit value after 48 hours of implantation. As a result, medium, high-Chitosan induced potential incompatibility in the tissue after 48 hours, but there was little effects to the skin inflammation. The values of biodegradable films, which prepared from natural polymers measured in this study were some satisfiable results at short period with those of ideal skin bioimplants and artificial skin.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.128-134
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• 2005

This study was performed to evaluate the strength and durability properties of recycled concrete containing water - redispersible copolymer powder(WRP) and blast furnace slag powder(BSP) [RCWS]. Material used were cemente, recycled coarse aggregare, natural fine aggregate, water-redispersible copolymer powder, blast-furnace slag powder. Especially, Water-redispersible powder was used for blending with Inorganic binders such as cemente, gypsum and hydrated lime etc. First of all, Mixed ratio method of RCWS made Two Type. One was called type-1 which used to BSP content 5% and WRP(Water-redispersible powder) content 0%, 1%, 2%, 3%, 4%, 5%, 6%. respectively. Another was called Type-2 which used to BSP(blast furnace slag powder)content 10% and WRP(Water-redispersible powder) content 0%, 1%, 2%, 3%, 4%, 5%, 6%. respectively. According to the experimental results of (RCWS), Incase Type-2 at curing age 28days, Compressive strength, pulse velocity and dynamic modulous of elasticity were shown higher than Type-1 and The more WRP content increasing($0%{\sim}6%$) was the lower Compressive strength, Pulse velocity and Dynamic modulous of elasticity. Water absorption ratio was in the range of $3.85%\;{\sim}\;3.23%$, it was almost equal to Type-1, 2 but Increasing the WRP content($0%{\sim}6%$), The water absorption ratio is decreased.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.287-292
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• 1999

The conducting composites were prepared by solution blending of polyaniline (PANI) as a conducting polymer and polycarbonate (PC) as a matrix in chloroform. Also the composites film was prepared by solution casting method. The PANI was protonated with alkylbenzenesulfonic acids, such as camphorsulfonic acid (CSA) or dodecylbenzenesulfonic acid (DBSA). The electrical conductivity of composites prepared by solution casting was enhanced compared with that of compression molding. The electrical conductivity, tensile strength and morphology were observed as a function of the amount of protonating agent as well as PANI complex content. In general, as the PANI complex content was increased, the electrical conductivity increased. In the case of the composite film containing 25 wt % of PANI complex doped with DBSA, the electrical conductivity exhibited 3.18 S/cm.