• Textile Coloration and Finishing
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• v.10 no.5
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• pp.56-62
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• 1998

In the prior study, the dyeing behaviors of Milling Cyanine 5R on silk fiber in aqueous dyeing liquor including small amount of organic compounds were investigated. The most effective compound was acetophenone which increased dye uptake as well as dyeing rate. In this study, the role of the acetophenone in dyeing of silk with Milling Cyanine 5R was studied. By addition of acetophenone into the dye solution, the molar absorptivity of Milling Cyanine 5R increased, and the wavelength of maximum absorption was shifted to longer wavelength, namely bathochromic shifted. This shows that the acetophenone prevents the dye to aggregate, and increases the number of monomeric dye molecule relative to the dye solution without acetophenone. This fact was also confirmed by the increase of the permeation rate of the dye through cellulose semipermeable membrane from the dye solution including the acetophenone. From these results, the acetophenone acts as a prohibitor of dye aggregation, increases the number of monomeric dye molecules even at relatively low temperature, and makes the dyes penetrate into the fiber easier.

• Textile Coloration and Finishing
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• v.1 no.1
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• pp.47-53
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• 1989

The effect of organic solvent in the dyeing of silk fiber by acid dye was investigated. Acetophenone and benzyl alcohol were shown to be the most effective for the rate of dyeing of silk fiber by Milling Cyanine 5R (C.I. Acid Blue 113), a milling type acid dye, but, with benzyl alcohol, the equilibrium dye uptake was much lower than that in the absence of it. In the presence of solvent, maximum dye uptake shifted to lower temperature than 6$0^{\circ}C$, while without solvent, it was shown at about $60^\circ{C}$. When dyed by Orange II (C.I. acid Orange 7) under same condition equilibrium dye uptake of silk fiber was lower than that for milling type acid dye, and in the presence of benzyl alcohol, still much lower uptake resulted. All these fact reveals that organic solvents in the solvent-assisted dyeing of silk fiber broaden micelle spacings too much, resulting in increased rate of dyeing, and decreased equilibrium dye uptake, contrary to wool.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.86-92
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• 2002

This paper presents a new model of NC verification in NC milling using z-map. The model can describe the motion of machine tool like a real machine effectively. The model uses x, y, and z directional feed rate as well as cutting data for modeling Z-map of workpiece. The model verifies the over-cut, the under-cut and the surface topography using NC codes and cutting conditions. To investigate the performance of the model, simulation study was carried out. As the results, the model gave the geometry accuracy of workpiece, the surface topography, and the chip loads.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.71-76
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• 2008

Micro end-milling is one of effective technology that is able to do ultra-precision machining while increasing the productivity and has wide application field. But selection of machining condition is very difficult because of complicated machining mechanism. Therefore this study was carried out to select working factors to get the optimum surface roughness. Machining condition are depth of cut, feed rate and spindle revolution. The result of this study showed that Surface roughness was affected, in the other of depth of cut, spindle revolution, feed rate. And this study provided an regression equation relating surface roughness to working factors through Regression Analysis and determination coefficient of regression equation had a satisfactory reliability of 79%.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.4
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• pp.181-185
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• 1997

The electrochemical properties of the $AB_2$-type (Zr-Ti-V-Ni-Cr-Co-Mn) metal hydride electrodes prepared by ball milling with $AB_5-type\{(LM)Ni_{3.6}Al_{0.4}Co_{0.7}Mn_{0.3}\}$(LM : Lanthanum-rich mischmetal) alloy powder as a surface activator were investigated. By ball milling with $AB_5$ type alloy powder, the activation of $AB_2$ type metal hydride electrode was accelerated resulting in an increase of discharge capacity from 35% to 85% of the maximum capacity at the first cycle. As the amount of surface activator increased the activation rate increased, whereas the discharge capacity increased with 10wt% and decreased with 20wt% addition of the surface activator. When the amount of the surface activator was kept constant as 10wt%, the discharge capacity and the activation rate increased with ball milling time up to 20 hours. However beyond 20 hours of ball milling time, they decreased drastically due to the nano-crystallization or amorphorzation of the alloy powder.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.79-88
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• 2002

High speed machining system have been used in industrial because it is effective to a material manufacturing with various shape. Recently the end-milling processing is needed the high-precise technique with good surface roughness and rapid time in aircraft, automobile part and molding industry. Therefore this study proposed to decide best manufacturing cutting condition for surface roughness and rapid manufacturing tune by using computer Image processing system and 3D modelling. Until the 16,000 rpm, the surface roughness is decreased rapidly, but it is not over that. The 22,000 rpm is the spindle speed with the optimum surface in the high speed end-milling. In the case of the feed rate with 2,000 mm/mm and 8,000 mm/mm, the surface roughness is better than 4,000 mm/min and 6,000 mm/min. By using the 3D modelling, it is effectively represented shape characteristics of working surface m high speed end-milling.

• Current Research on Agriculture and Life Sciences
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• v.32 no.2
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• pp.91-97
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• 2014

In order to analyze the structural factors and milling performance of farmhouse rice milling machines in Korea, this study classified 29 models of the farmhouse rice milling machines sold in Korea into hulling and polishing devices, examined the structural features for each device, and then analyzed the performance factors based on the results. With regard to hulling devices, impeller rotational speed was investigated as a major structural factor. The hulling devices at an impeller rotational speed of 4,800 rpm were most frequently used and accounted for the largest proportion, 65.5%. At this rotational speed, the hulling rate was the highest, 99.45%, and the brown rice cracked rate was the lowest. Thus, the best impeller rotational speed for the hulling performance was analyzed as 4,800 rpm (p<0.05). With regard to polishing devices, rotor speed was investigated as a major structural factor. The polishing devices with a rotor linear velocity of 2 m/s were most commonly used and accounted for the largest proportion, 60.1%. At this linear velocity, the hulling rate was the highest with 75.07%, and the dispassion rate and broken rice rate were the lowest with 0.02 and 7.06%, respectively. Thus, the best rotor linear velocity for the polishing performance was analyzed as 2 m/s (p<0.05).

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.299-299
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• 2022

Whole wheat is rich in dietary fiber and contains various biological activity substances such as arabinoxylan, phytic acid and phenolic compounds. However, excessive fiber contents of whole wheat has a negative effect on dough formation, making it difficult to process. In this study, we tried to improve the usability of whole wheat by suggesting an appropriate degree of purification of whole wheat from 'Saekeumkang', a domestic wheat cultivar containing protein and gluten suitable for noodle production. The contents of arabinoxylan, phytic acid, and vitamin E were measured in the polishing rate range of 5-20% of whole wheat flour. As the milling ratio increased, the flour properties improved. The arabinoxylan and phytic acid content of whole wheat were 67.95 mg/g and 0.87 mg/g, but when milled at 20%, arabinoxylan and phytic acid were 60% and 80% of whole wheat, respectively. And as the milling ratio increased, the vitamin E content tended to decrease (whole wheat: 4.063 mg/100 g, 20% milled: 2.96 mg/100 g), However, the vitamin E composition ratio did not change. On the other hand, α-tocopherol showed the greatest than other vitamin E isomers. Therefore, further studies needed to optimize milling rate to improve the final product while maintaining the approximate nutritional and functional value of the whole wheat.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.86-91
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• 2016

End milling is an important and common machining operation because of its versatility and capability to produce various profiles and curved surfaces. This paper presents an experimental study of the cutting force variations in the end milling of SM25C with HSS(high speed steel) and carbide tool. This paper involves a study of the Taguchi design application to optimize cutting force in a end milling operation. The Taguchi design is an efficient and effective experimental method in which a response variable can be optimized, given various control and noise factors, using fewer resources than a factorial design. This study included feed rate, spindle speed and depth of cut as control factors, and the noise factors were different cutting tool in the same specification. An orthogonal array of $L_9(3^3)$ of ANOVA analyses were carried out to identify the significant factors affecting cutting force, and the optimal cutting combination was determined by seeking the best cutting force and signal-to-noise ratio. Finally, confirmation tests verified that the Taguchi design was successful in optimizing end milling parameters for cutting force.

• Korean Journal of Materials Research
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• v.29 no.4
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• pp.233-240
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• 2019

This study analyzes the mechanical properties, including the attrition rate, of $50{\mu}m$ size yttria-stabilized zirconia (YSZ) beads with different microstructures and high-energy milling conditions. The yttria distribution in the grain and grain-boundary of the fully sintered beads relates closely to Vickers hardness and the attrition rate of the YSZ beads. Grain size, fractured surfaces, and yttrium distribution are analyzed by electronic microscopes. For standardization and a reliable comparison of the attrition rate of zirconia beads with different conditions, Zr content in milled ceramic powder is analyzed and calculated by X-ray Fluorescence Spectrometer(XRF) instead of directly measuring the weight change of milled YSZ beads. The beads with small grain sizes sintered at lower temperature exhibit a higher Vickers hardness and lower attrition rate. The attrition rate of $50{\mu}m$ YSZ beads is measured and compared with the various materials properties of ceramic powders used for high-energy milling. The attrition rate of beads appears to be closely related to the Vickers hardness of ceramic materials used for milling, and demonstrates more than a 10 times higher attrition rate with Alumina(Hv ~1650) powder than $BaTiO_3$ powder (Hv ~315).