• Journal of Fisheries and Marine Sciences Education
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• v.4 no.1
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• pp.62-74
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• 1992

The effect of additional amounts of subsidiary materials on texture of fish meat paste were examined using Instron Universal Testing Machine to obtain fundamental data for steamed Alaska pollack meat paste showing good quality. The hardness revealed the good correlation with jelly strength among the six kinds of parameters of Instron texturometer. Products with higher hardness showed a better quality, but those with hardness higher than 16kg showed decreasing quality with increasing hardness. Predicting the quality of steamed Alaska pollack meat paste with various additional amounts of subsidiary materials as a function of hardness, H, the equation could be deduced as follows: H=11.56+0.54Xcs, H=12.22-0.23Xsp and H=11.65-7.13Xpp. The reasonable equations for predicting the quality of steamed Alaska pollack meat paste with various additional amounts of mixed subsidiary materials could be summarized as follows: H=11.57+0.53Xcs+0.44Xsp, H=11.97-1.83Xpp-0.17Xcs, and H=11.58+0.08Xpp-0.23Xsp.

• Journal of Ocean Engineering and Technology
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• v.26 no.2
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• pp.33-38
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• 2012

The effects of the diffusible hydrogen content and hardness on the cold cracking in high strength weld metal were investigated. The diffusible hydrogen contents were influenced by welding parameters such as the voltage and contact tip-to-work distance (CTWD). The diffusible hydrogen content increased with an increase in voltage. However, it was decreased with an increase in CTWD. CTWD also influenced the weld metal hardness,especially when the wire used had a higher strength than the base metal. This showed that weld metal hardness had a more powerful effect on weld metal cold cracking than the diffusible hydrogen content in this experiment.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.552-553
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• 2006

The present study investigates the behavior of the sintering and hardness of stainless steel samples reinforced with NbC and TaC. Matrixes of pure stainless steel were compacted with addition of up to 3% wt NbC or TaC in a cylindrical die of steel $(\phi\;=\;5,0\;mm)$ at 700 MPa and sintered in an electrical resistance furnace under argon atmosphere. The sintered samples were characterized by density and hardness measurement, optical microscopy and scanning electron microscopy (SEM). The preliminary results show that the size and distribution of carbides influence in the sintering and hardness of the sintered samples.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.340-345
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• 2001

Surface hardness is one of the major sources on wear in the oil hydraulic axial piston pump. To increase the performance of the oil hydraulic axial piston pump, it is need to know the surface layer characteristics in the sliding contact parts of them. This paper reports an experimental study on surface treatment characteristics in the piston of the oil hydraulic axial piston pump. We investigated surface wear with not only surface hardness and surface roughness but also material of the piston. We obviously observed that the surface hardness of piston in the oil hydraulic axial piston pump plays an important role to high power density and remain long life.

• Journal of Pharmaceutical Investigation
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• v.1 no.1
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• pp.70-77
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• 1971

The ointment, had discovered and used from the ancient, have not ever defined to qualitity as the hardness concerned with the absorned With the absorption of the effect of durg through the skin. Auther, for the first time, suggest the apparent logarithmic hardness against the penetration of ointment registered on the pharmacopeia of the Republic of Korea, the results are as the followings. 1. The speciality of this apparent logarithmic hardness ie in proportion for the solidity on the contrary to the penetration of oiniment, and the distribution range of it are between 1.68 to 3.53 for their ointments examined. 2. The specific gravity of the verious ointments according to the apparent logarithmic hardness may be ignore on the calculaiotn, the mean valve of the samples was 2.9303. 3. The determination of apparent logarithmic hardness(H) by the penetration method follows the under equation. $H=log_{10}({\frac{P-0.545h^3}{0.855h^2}})$ where, the h is the penetrate length described centimeter, and p is the weight of the cone.

• Journal of Applied Reliability
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• v.16 no.2
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• pp.155-161
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• 2016

Purpose: Purpose of this study is to analyze the effect of particle size as well as number of pass on surface microstructure and hardness of SiC(p)/AZ31 surface composite fabricated by friction stir process (FSP). Method: SiC(p)/AZ31 surface composite containing different size of SiC particle (i. e., $2{\mu}m$ and $8{\mu}m$) was fabricated by multi-pass FSP. Microstructure was observed by scanning electron microscope and surface hardness was determined by Vickers hardness tester. Results: For all the FSPed specimens with and without hardening particles, grain size was refined due to dynamic recrystallization behavior. Surface hardness was observed to increase with decreasing particle size in the composite layer. Increasing number of FSP pass was effective for homogeneous distribution of the hardening particles and for resulting increase in surface hardness. Conclusion: FSP was effective to modify surface microstructure for improving surface hardness of SiC/AZ31 composite.

• Journal of Welding and Joining
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• v.33 no.1
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• pp.61-71
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• 2015

The effect of welding condition on microstructure and mechanical property of Plasma-MIG Hybrid Weld between Al 5083 plates(thickness : 10mm) was investigated. 1 pass weld without any defects such as puckering, undercut, and lack of fusion was obtained by 150~200A of plasma current and 5~7mm of welding speed. Gas porosities and shrinkage porosities were existed in the weld near fusion line. As welding speed and plasma current were decreasing, the area fraction of porosity was increasing. The hardness of the weld is increasing as welding speed. On the basis of microstructural analysis, Mg segregated region near dendrite boundaries tends to increase with the welding speed. In the result of hardness test, Distribution of hardness in fusion zone showed little change with the plasma current. However, when the welding speed increased, hardness in weld metal markdly increased. It could be considered that effect of heat input to growth of the dendritic solidification structures. Based on tensile test, tensile properties of weld metal was predominated by area fraction of porosities. Consequently, tensile properties can be controlled by formation site and area fraction of porosity.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.217-222
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• 1995

Experiments were conducted to study the effect of IBA, mineral stone and stem hardness on rooting characteristics in mature Aloe vera plant. The rooting ability in matured Aloe vera was of highly significance when the amount of IBA treatment was increased to 5.000mg/l. The treatment of IBA 5.000mg/l, together with mineral stone(v/w 1.5 times), gave more root number, the length and the dry weight of root were, also, higher in semihard wood cutting than soft wood cutting in matured Aloe vera.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.813-823
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• 2023

In this study, microstructure, hardening layer hardness, and case depth were evaluated after induction hardening(IH) of base metal specimen(BM) treated with annealing and quenching-tempering specimen(QT) treated with quenching and tempering. The microstructure after IH was significantly influenced by the microstructure before IH and the induction coil heating movement speed, but the effect of the induction frequency was very small. The hardness of the hardened layer at an induction coil heating movement speed of 15 mm/s or less was more influenced by the microstructure before IH than the induction coil travel speed and induction frequency. The induction coil travel speed has the significantly effect on the case depth, the induction frequency has effect and the microstructure before IH has a small effect.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.2
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• pp.166-173
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• 1999

Commercial carbon steels containing 0.2~0.55 wt.----C were plasma-nitrided or plasma nitrocarburized at $550^{\circ}C$ for 21.6Ks using $H_2-N_2$ or $H_2-N_2$-CO mixed gas respectively. The characteristics of hardening and wear-resistance of each treatment were studied and compared. And also microstructure of nitrided layer and nitrides formed in compound layer near surface were studied. All plasma-nitrided steels investigated showed remarkable increase of surface hardness with the increase of carbon content. But nitrocarburized steels resulted in higher surface-hardness than plasma-nitrided steels, which means that nitrocarburized has higher surface-hardening effect. Plasma-nitrided steels showed hardness increase in through-thickness direction near surface. And also nitrocarburized steels showed similar hardness distribution in through-thickness direction to that of plasma-nitrided steel. However, nitrocarburized steels had higher cross-sectional maximum-hardness than plasma-nitrided steels as much as 100Hv. Wear test showed that the amount of specific wear was reduced by both plasma-nitriding and nitrocarburized, showing that the amount of specific wear was not related to the hardness. But non-treated specimen showed that the amount of specific wear was related to the hardness.