• Korean Journal of Materials Research
• /
• v.24 no.9
• /
• pp.488-494
• /
• 2014

The effect of tungsten (W) addition on the hardenability of low-carbon boron steels was investigated using dilatometry, microstructural observations and secondary ion mass spectroscopy. The hardenability was discussed with respect to transformation behaviour aspects depending on the segregation and precipitation of boron at austenite grain boundaries. A critical cooling rate producing a hardness corresponding to 90 % martensite structure was measured from a hardness distribution plot, and was used as a criterion to estimate hardenability at faster cooling rates. In the low-carbon boron steel, the addition of 0.50 wt.% W was comparable to that of 0.20 wt.% molybdenum in terms of critical cooling rate, indicating hardenability at faster cooling rates. However, the addition of 0.50 wt.% W was not more effective than the addition of .0.20 wt.% molybdenum at slower cooling rates. The addition of 0.20 wt.% molybdenum completely suppressed the formation of eutectoid ferrite even at the slow cooling rate of $0.2^{\circ}C/s$, while the addition of 0.50 wt.% W did not, even at the cooling rate of $1.0^{\circ}C/s$. Therefore, it was found that the effect of alloying elements on the hardenability of low-carbon boron steels can be differently evaluated according to cooling rate.

• Journal of the Korean Home Economics Association
• /
• v.44 no.3 s.217
• /
• pp.163-169
• /
• 2006

The effects of adding Angelica plant (Bakluncho) and Angelica gigas (Senggumcho) powders on the quality characteristics of bread were investigated. The moisture, crude protein, ash, reducing sugar and vitamin C contents of Angelica plant (Bakluncho) powder were 7.78%, 6.07%, 7.37%, 6.13% and 50.10mg%, respectively, and of Angelica gigas (Senggumcho) powder were 8.69%, 12.28%, 5.15%, 2.21% and 108.00mg%, respectively. The lightness value decreased but the redness and yellowness values increased with the addition of Angelica plant (Bakluncho) and Angelica gigas (Senggumcho) powders. The mechanical hardness of bread decreased with the addition of 3% of Angelica plant (Bakluncho) powder, but increased with the addition of 1% and 5% of Angelica plant (Bakluncho) powder. The mechanical hardness of bread decreased with the addition of 1%, 3% and 5% of Angelica gigas (Senggumcho) powder. In sensory characteristics, the crust color, crumb color, moistness and springiness decreased, but aroma and hardness increased with the addition of Angelica plant (Bakluncho) and Angelica gigas (Senggumcho) powders. The savory taste and overall quality of breads with 1% Angelica plant (Bakluncho) and 1% Angelica gigas (Senggumcho) powders were higher than without either powder. A negative correlation was observed between mechanical hardness and overall bread quality with the addition of Angelica plant (Bakluncho) powder, while a positive correlation (p<0.01) was observed with the addition of Angelica gigas (Senggumcho) powder.

• Journal of Environmental Science International
• /
• v.15 no.6
• /
• pp.563-569
• /
• 2006

It was compared the reduction effect of contaminants and odor according to DO change and EM (effective microorganisms) addition in maturation process of piggery slurry. The maturation processes were divided into three cases as follows: R-1 was operated at $2.5mg/{\ell}$ of DO without the addition of EM, R-2 was operated at $7.5mg/{\ell}$ of DO without the addition of EM and R-3 was operated at $2.5mg/{\ell}$ of DO with the addition of EM. The addition of EM was more effective than the increase of DO for the reduction of CODcr, $NH_3-N$ and T-N in the maturation of piggery slurry. In addition, the reducing effect of odor intensity appeared high even in the short-term maturation period in case of adding EM and one could not even smell the stimulating odor of piggery slurry.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.30 no.4
• /
• pp.42-48
• /
• 1998

The bacterial cellulose(BC) has many unique properties that are potentially and commercially beneficial. In order to enhance inherently inferior physical property of chemithermomechanical pulp(CTMP) sheet, chemical pulp has been used widely. Bacterial cellulose also has an enhanced sheet strength because of its unique physical and morphological features. This study was carried out to inverstigate the effect of BC addition on physical properties of CTMP sheets. The effect of BC addition on its optical properties was also discussed. The apparent density, internal bond strength, Young's modulus, tensile strength and folding endurance of CTMP sheet are increasing with increase of BC contents. This strength increase would be attributed to the increase of relative bonding sites among pulp fibers by addition of BC which has microfibrillar structure with very high specific surface areas. There were not so significant changes in opacity of CTMP sheet upto 20% addition level of BC, while over 40% addition, the opacity gradually decreased and levelled off. Porosity is decreased with addition of BC. This decrease would be attributed to densification of sheet by fine and filamentous structure of BC fibers.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.10 no.4
• /
• pp.288-294
• /
• 2017

Recently, deep learning using convolutional neural network (CNN) has been extensively studied in image recognition. Convolution consists of addition and multiplication. Multiplication is computationally expensive in hardware implementation, relative to addition. It is also important factor limiting a chip design in an embedded deep learning system. In this paper, I propose a parallel-addition processing algorithm that converts grayscale images to the superposition of binary images and performs convolution only with addition. It is confirmed that the convolution can be performed by a parallel-addition method capable of reducing the processing time in experiment for verifying the availability of proposed algorithm.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.43 no.4
• /
• pp.23-30
• /
• 2011

Fillers have been used for papermaking in order to enhance the optical properties, to improve sheet formation, printability and dimensional stability and to reduce the furnish cost. However, filler particles in paper interfere with fiber-fiber bonding, resulting in decreased paper strength. In order to increase filler content in paper without sacrificing too much paper strength, dual addition technology of fillers was investigated. As a first step, the effects of thick stock addition of fillers on paper properties and papermaking process were elucidated. It was shown that thick stock addition of fillers could increase paper strength at a given filler content. No significant adverse effects on formation, drainage and filler retention were observed. However, bulk of paper was reduced with thick stock addition of fillers, which shall be resolved with regulating other factors such as the mixing ratio of pulps and type of fillers.

• Culinary science and hospitality research
• /
• v.22 no.8
• /
• pp.67-77
• /
• 2016

This study investigated the physicochemical, antioxidative activity, and sensory characteristics of yanggaeng prepared with various amounts of peach powder. According to the results, the pH of yanggaeng was decreased significantly by addition peach powder, but total titratable acidity of yanggaeng was increased significantly by addition peach powder. The sweetness ($^{\circ}brix%$) and moisture content of groups by the addition of peach powder were lower than those of control group. At the result of color measurement, L value of groups by the addition of peach powder was lower than that of control group, but a value and b value of groups by the addition of peach powder were higher. Texture measurement score in terms of hardness and brittleness for yanggaeng were increased significantly by addition peach powder. The contents of DPPH radical scavenging activity, and ABTS radical scavenging activity of groups by the addition of peach powder were higher than those of control group. As peach powder increased, antioxidative activity also became bigger. Sensory evaluation scores in terms of after swallowing, appearance, odor, taste, texture, and overall preference of groups with 4% and 6% peach powder were higher significantly when compared to the control group.

• Journal of the Korean Ceramic Society
• /
• v.23 no.5
• /
• pp.9-16
• /
• 1986

The effect of $TiO_2$ addition to the 90wt% Cordierite-10wt% Enstatite base glass was investi-gated to understand the crystallization behavior of the glass. Glasses with addition of $TiO_2$ less than 7, 5wt% had a tendency of surface crystallization and were cracked when heat treated and in this case the crystalline phase formed was indialite. glasses with addition of $TiO_2$ more than 10wt% to 15wt% were crystallized in bulk when heat treated and were suitable for glass-ceramics. The highest microhardness 1640kg/$mm^2$ was obtained when the glass of 12.5wt% $TiO_2$ addition was heat treated at 762$^{\circ}C$ for 60 minutes for nucleation and at 1135$^{\circ}C$ for 20 minutes for crystal growth and in general higher microhardness was obtained when crystalline phase of magnesium aluminum titanate and $\mu$-cordierite were developed. Avrami equation for crystal growth kinetics was applicable in glasses of less than 7.5 wt% $TiO_2$ addition and in case of glasses of more than 10wt% $TiO_2$ addition it was not applicable because of too fast crystal growth.

• Journal of Korea Foundry Society
• /
• v.36 no.6
• /
• pp.195-201
• /
• 2016

The effects of Mg addition on heat treatment and mechanical properties of A356 alloy were investigated. With increased amounts of Mg addition to A356 alloy, the grain size decreased and eutectic Si was refined. And, this process can improve the mechanical properties. Solid solution heat treatment causes the spheroidizing of eutectic Si. In this study, although eutectic Si was refined with Mg addition, solid solution time increased from 2 hours to 6 hours with Mg addition, and aging time also increased, from 4 hours to 8 hours. After heat treatment, Mg2Si remained in a formation of Chinese script. And, Chinese script Mg2Si formed with Mg addition caused a reduction of the elongation of the alloys according to the stress concentration.

• Journal of the Korean Applied Science and Technology
• /
• v.12 no.2
• /
• pp.85-92
• /
• 1995

The rate constant of the nucleophilic addition of 1-propanethiol to ${\alpha}-phenyl-N-iso-propylnitrone$ derivatives were determined at various pH and a rate equation which can be applied over wide pH range is obtained. Final product of the addition reaction was ${\alpha}-thiopropyl-p-phenylbenzylideneamine$. Base on the rate equation, general base effect, substituent effect and final product, plausible mechanism of addition reaction have been proposed. Below pH 3.0, the reaction was initiated by the addition of 1-propanthiol, and in the range of pH 3.0-10.0, proceeded by the competitive addition of 1-propanethiol and propanethiolate. Above the pH 10.0, the reaction proceeded through the addition of propanethiolate.