• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.5
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• pp.567-573
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• 2016

GMAW and GTAW processes have been used for welding of equipment mounting pads during decades. For improving the mobility and survivability of KWV(Korean Wheeled Vehicle), various types of equipment are required and numbers of pads for welding were increased. In this research, for improving productivity of mounting pads welding process, new technology of stud welding was studied. In this study, mechanical properties of stud weldment were investigated to compare with those of GMAW weldment. Also, research of stud weldment durability was carried out and proved its fatigue strength under the condition of KWV's 32,000 km load profile.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.713-719
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• 2010

The objective of this study was to evaluate the quality characteristics of Dasik containing different levels of jujube paste (0%, 60%, 70%, 80%, 90%). Moisture composition of the paste ranged from 19~29% As the content of jujube paste increased, the lightness (L) and yellowness (b) decreased while redness (a) increased In the texture profile analysis, as the content of jujube paste in Dasik content increased, the hardness decreased Cohesiveness and springiness did not show significant differences according to amount of jujube paste. The results of the sensory evaluation show that sweetness, bitterness, and overall acceptability were the highest in Dasik containing 80% level jujube paste.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.249-252
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• 1999

Boriding is one of the chemical method to increase surface hardness as well as carburizing, and nitriding. Gas boriding and boron paste boriding methods were investigated to replace salt bath boriding. Boron paste boriding method is selected due to safety, small waste and low cost. And then boriding is also carried out micro-pulsed PECVD in order to increase efficiency of boriding. Mechanical properties, microstructure, surface concentration, and depth profile of borided layer is investigated by micro-vickers hardness tester, SEM, XRD, and AES.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.176-183
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• 2005

Laser heat treatment technology is used for improving the feature of fatigue resistance and wear resistance in mobile parts. The purpose of this study is to compare the characteristics of laser heat treatment and high frequency heat treatment, which is commonly used in industrial place. For the preemptive experiment, the distribution, depth and size of hardening and its micro-structural features were compared between surface heat treatment case by defocusing and variables of each process for heat treatment by exclusively manufactured heat treatment optical system. As a result, high frequency heat treatment has wide distribution of hardening depth and width about 3 times larger than laser heat treatment, however, its average hardness showed 621.4Hv which is smaller than the average hardness of laser heat treatment with 691Hv.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.521-524
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• 2016

This study aimed to examine variations in the texture profile analysis (TPA) of cooked rice in relation to the instrumental parameter conditions. The TPA of four types of ready-to-eat, white rice products was conducted in two levels of compression ratio (30 and 70%) and cross-head speed (0.5 and 1.0 mm/s). The properties of the four rice products significantly or non-significantly differed, depending on the instrumental parameter condition. Agglomerative hierarchical clustering, based on the five TPA properties such as hardness, adhesiveness, cohesiveness, chewiness, and springiness, revealed that clustering of the four rice products varied with the instrumental parameter condition. Additionally, the ratio of adhesiveness to hardness, an index of rice texture quality, showed a variation depending on the two instrumental parameter conditions. In conclusion, our findings demonstrate that the texture profile, texture-based sample clustering, and the ratio of adhesiveness to hardness vary with the compression ratio and cross-head speed in the TPA.

• Transactions of Materials Processing
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• v.4 no.2
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• pp.123-130
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• 1995

The present study is concerned with the hydrostatic extrusion process for the copper-clad aluminum rod through metallurgical joining. The rigid viscoplastic finite element analyses are performed for the steady state extrusion process of the bimetal rod. An algorithm for finding the interface profile of the bimetal rod by tracking a particle path in Eulerian domain is presented. The distributions of the effective strain rate, equivalent stress and hardness are examined for the several extrusion ratios. Experiments are also carried out for the copper-clad aluminum rod at room temperature. It is found out that the finite element predictions are generally in good agreement with the experimental observations. The detail comparisons of the extrusion loads predicted by the element method with those by experiments are given.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.519-524
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• 1999

To manufacture alumina products, sintering and grinding process are needed. In Al2O3 grinding, macro/micro surface fracture and cracks are easily occurred on the ground surface because of its high brittleness. In view point of fatigue fracture, surface profile produced by grinding is considered as notches. Therefore, it was reasonable that magnitudes and shapes of surface profiles effects on fatigue strength and life. Particularly, surface finish of Al2O3 which have high hardness and brittleness have an effect on fatigue strength. In this paper, some experiments are carried out to examine influence of grinding conditions to magnitude and shape of surface profile as well as the relationships of Ra, Rmax, Rmax/Ra, and Ku. Through the experimental results, It is found that Ra and Rmax was affected by grinding conditions, but Rmax/Ra and Ku was not. There are linear relations between Ra and Rmax, and between Rmax/Ra and Ku.

• Journal of the Korean Society for Heat Treatment
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• v.19 no.5
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• pp.262-269
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• 2006

The development of eco-friendly low pressure carburizing system with high pressure gas quenching(LPC-GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.81-86
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• 2002

Yackwa was prepared by the addition of different amounts of egg white, and the samples were analyzed by texture profile analysis, Hunter's colorimetry and sensory evaluation during 5 days of storage. Tn texture profile analysis, the hardness, gumminess and chewiness of Yackwa were increased in all the samples during storage and the texture parameters were increased by increasing egg white level. No significant difference was observed in the lightness, redness and yellowness (p〉0.05), but Hunter's color values were slightly increased during storage in all the samples. In sensory evaluation, no significant difference was observed among the samples during storage except the increase of crispiness and overall acceptance by the addition of egg white. The results showed that Yackwa prepared with 10 g of egg white/(100 g of other ingredients ---약과재료 얼마당 10g 첨가인지 명확히 해야 함) had an acceptable sensory quality.

• Culinary science and hospitality research
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• v.11 no.3 s.26
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• pp.179-189
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• 2005

The purpose of this study was to investigigate the effects of different tapioca powder on the quality of Chol-Pyon. As the result of the sensory evaluation, 5% addition groups showed good preference in chewness, moistness, softness, adhesiveness, after flavor. 10% addition groups showed good preference moistness, softness, after flavor. In texture profile, gumminess, cohesiveness, adhesiveness of Chol-Pyon was not different significantly among all the groups. All groups was getting higher by addition level. Softness was 5%, 20% addition groups had the higher. Tapioca Chol-Pyon seemed to increase hardness slightly. 5% addition group had the highest values in chewness. The desireable water content in 5%, 10% Tapioca Chol-Pyon was not different significantly among all the groups(p<0.05). 15%, 20% addition group was significantly different from all the groups. Hunter's rotor values higher redness and yellowness was 20% tapioca powder addition group more than the other groups but lightness were lowest value. Above results indicated that 5% tapioca powder addition level to give the best quality.