• Journal of Power System Engineering
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• v.7 no.4
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• pp.55-60
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• 2003

This paper is to investigate the fatigue crack growth of plasma-sprayed coating steels according to heat treatments. The experimental materials are carbon steels(substrate: S45C) with plasma-sprayed coating layers of Ni-4.5%Al and $TiO_2$. The fatigue test is conducted on compact tension specimen by a servo-hydraulic fatigue testing machine. The specimens are heat-treated at $400^{\circ}C\;and\;800^{\circ}C$, respectively. Loading condition is a constant amplitude sinusoidal wave with a frequency of 10Hz and a load ratio of 0.1. The fatigue crack growth length is automatically measured by a compliance method. In the case of non-heat treated specimens, the fatigue crack growth rates of both substrate and coating specimen are almost same. The crack growth rates of substrates and coating steels by heat treatment are larger than those of the non-heat treated one, because the ductile property increase by heat treatment. In ${\Delta}K<18MPa{\cdot}m^{1/2}$, the crack growth rates of the heat-treated specimens are slightly taster than non-heat treated one. But the both heated and non-heated one are almost same in ${\Delta}K>18MPa{\cdot}m^{1/2}$.

• International Journal of Computer Science & Network Security
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• v.21 no.2
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• pp.9-13
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• 2021

Type 2 diabetes mellitus (T2D) is a complex diabetes disease that is caused by high blood sugar, insulin resistance, and a relative lack of insulin. Many studies are trying to predict variant genes that causes this disease by using a sample disease model. In this paper we predict diabetic and normal persons by using fisher score feature selection, chi-2 feature selection and Logistic Regression supervised learning algorithm with best accuracy of 90.23%.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.2
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• pp.51-57
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• 2010

The shape of the register mark for the image processing becomes very important, because the printing quality is determined by the error correction between the register marks for the image processing. In this paper, printing marks are developed using the image process for the gravure printing method which is commonly being used in roll to roll, high resolution printing. The marks which can be cited to the flexible display print are developed The developed register marks which satisfies 10[${\mu}m$] error tolerance are tested under 70[mpm] printing conditions and confirmed through the experiments.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.1
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• pp.1-12
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• 1995

For the purpose of this study, the silicoating on Ni-Cr-Be alloy surface was carried out by using the Silicoater MD. The effect of time delay after silicoating on the bond strength between the metal and resin cement was examined. The groups were divided into 4 : group 1 : Sandblasted with $250{\mu}m$ aluminium oxide, immediatly cemented group 2 : Sandblasted with $250{\mu}m$ aluminium oxide, silicoated and immediatly cemented group 3 : Sandblasted with $250{\mu}m$ aluminium oxide, silicoated and cemented after 7 days group 4 : Sandblasted with $250{\mu}m$ aluminium oxide, silicoated and coated with unfilled resin and cemented after 7 days Specimens were luted with Comspan, Superbond C&B or Panavia EX. The tensile bond strength between the metal and resin cement was measured by using the universal testing machine. The results were as follows : 1. The bond strength in groups 2, 3 and 4 was higher than that of group 1 (p<0.05). There was no statistically significant difference among the bond strength in groups 2, 3 and 4 (p>0.05). 2. In Comspan-cemented groups, there was no significant difference among the bond strength in groups 2, 3 and 4 (p<0.05). 3. In Panavia EX-cemented groups, the bond strength of group 3 was higher than that of group 2 (p<0.05) and there was no significant difference between groups 3 and 4. 4. In Superbond C&B-cemented groups, there was significant difference between groups 2 and 3 (p<0.05) and the bond strength of group 4 was higher than that of group 3 (p<0.05). 5. The highest tensile bond strength was obtained by using the Superbond C&B and no difference in the Panavia EX and Comspan. 6. The modes of bond failure were mainly cohesive failure. The method of storage and transport indicated in this study seems recommendable for laboratory and clinical use at least up to 7 days.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.425-431
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• 1996

KT-2 poloidal-field (PF) system is designed to cope the up-down symmetric double-null (DN) and asymmetric single-null (SN) discharges with typical plasma parameters, in which three sets of "design-basis" scenarios - the ohmic heating (OH), the 5MW and the high bootstrap (HIBS) baseline modes - are applied. The power and energy demand for each cases are also deduced. The peak power and the maximum energy requirements for the KT-2 magnet system, incorporating the PF and the toroidal-field (TF) coils, are proven to be 123MW and 1601MJ, respectively when it is driven in DN configuration. The KT-2 PF system is capable of achieving the machine mission of creating a 500kA heated plasma with a current flattop of $\geq$20 seconds.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.485-493
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• 2013

PURPOSE. To evaluate the effects of surface treatments on shear bond strength (SBS) between microwave and conventionally sintered zirconia core/veneers. MATERIALS AND METHODS. 96 disc shaped Noritake Alliance zirconia specimens were fabricated using YenaDent CAM unit and were divided in 2 groups with respect to microwave or conventional methods (n=48/group). Surface roughness (Ra) evaluation was made with a profilometer on randomly selected microwave (n=10) and conventionally sintered (n=10) cores. Specimens were then assessed into 4 subgroups according to surface treatments applied (n=12/group). Groups for microwave (M) and conventionally (C) sintered core specimens were as follows; $M_C$,$C_C$: untreated (control group), $M_1,C_1:Al_2O_3$ sandblasting, $M_2,C_2$:liner, $M_3,C_3:Al_2O_3$ sandblasting followed by liner. Veneer ceramic was fired on zirconia cores and specimens were thermocycled (6000 cycles between $5^{\circ}-55^{\circ}C$). All specimens were subjected to SBS test using a universal testing machine at 0.5 mm/min, failure were evaluated under an optical microscope. Data were statistically analyzed using Shapiro Wilk, Levene, Post-hoc Tukey HSD and Student's t tests, Two-Way-Variance- Analysis and One-Way-Variance-Analysis (${\alpha}$=.05). RESULTS. Conventionally sintered specimens ($1.06{\pm}0.32{\mu}m$) showed rougher surfaces compared to microwave sintered ones ($0.76{\pm}0.32{\mu}m$)(P=.046), however, no correlation was found between SBS and surface roughness (r=-0.109, P=.658). The statistical comparison of the shear bond strengths of $C_3$ and $C_1$ group (P=.015); $C_C$ and $M_C$ group (P=.004) and $C_3$ and $M_3$ group presented statistically higher (P=.005) values. While adhesive failure was not seen in any of the groups, cohesive and combined patterns were seen in all groups. CONCLUSION. Based on the results of this in-vitro study, $Al_2O_{3-}$ sandblasting followed by liner application on conventionally sintered zirconia cores may be preferred to enhance bond strength.

• Journal of Biosystems Engineering
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• v.40 no.2
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• pp.102-109
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• 2015

Purpose: Slow manual harvesting of rain-fed chickpeas cultivated in fallow fields in developing countries have encouraged the design of a mechanical harvester. Methods: A tractor-pulled harvester was built, in which a modified stripper header detached pods from an anchored plant and a chain conveyor transferred material. The stripper harvester was redesigned to use: 1) the maneuverability of tractor-mounted frames, 2) the adaptability of floating headers, and 3) the flexibility of pneumatic conveyors. Results: A mobile vacuum conveyor, which was an innovator open system, was designed for the dilute phase transferring mode for both grain and material other than grain. A centrifugal fan transferred harvested material to a cyclone separator that settled harvested material in a grain tank 1 m high. The machine at the spot work rate of $0.42ha{\cdot}h^{-1}$ harvested chickpea pods equal to the output of 16.6 farm laborers. Conclusion: The low cost and reasonable projected purchase price are the advantages of the concept. Additionally, the shattering loss reduction confirms the feasibility of the prototype chickpea harvester for commercialization.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.5
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• pp.578-583
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• 2016

In order to provide a basis data for design of small arms and their silencer, an experimental study on firing noise of small arms was performed around the muzzle of a gun. For this experimental comparison analysis, the target small arms were included most operating small arms in our country. The sound pressure levels were measured at a certain distance which was predetermined according to US army firing test procedure, TOP 3-2-045. By this experimental study, the sound pressure levels of 5.56 mm caliber small arms are 143 dB ~ 145.4 dB and 7.62 mm caliber small arms are 144 dB ~ 145.2 dB. Between the heavy machine gun K12 and M60, the sound pressure level of K12 is slightly lower than M60.Also silencer for K14 snifer rifle was tested. Using this result, it has been found that the reduction effect of the silencer is 15.4 dB but the improvements of silencer performance in the high frequency range have to be studied later on.

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1162-1171
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• 1998

This paper presents a data structure that implements a mergable double-ended priority queue : namely an improved relaxed min-max-pair heap. By means of this new data structure, we suggest a parallel algorithm to merge priority queues organized in two relaxed heaps of different sizes, n and k, respectively. This new data-structure eliminates the blossomed tree and the lazying method used to merge the relaxed min-max heaps in [9]. As a result, employing max($2^{i-1}$,[(m+1/4)]) processors, this algorithm requires O(log(log(n/k))${\times}$log(n)) time. Also, on the MarPar machine, this method achieves a 35.205-fold speedup with 64 processors to merge 8 million data items which consist of two relaxed min-max heaps of different sizes.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.2
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• pp.95-99
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• 2017

The recent development of core techniques in the IT industry can be summarized as a technical advancement for safety and convenience, and mechanical technology for being "eco-friendly" and lightweight. Under these circumstances, research of lightweight material has become attractive. In this study, CFRP (Carbon Fiber Reinforced Plastic) laminate specimens are subjected to a tensile test using the UTM(Universal Testing Machine, AG-IS 100 kN) to estimate their mechanical properties in terms of the Hole machining impact evaluation. The FEM (Finite Elements Method) analysis method is applied and the material properties obtained from basic experiments such as the Tensile test, the compressive test, and the shear test. CFRP materials properties from a previous study, as well as a finite element analysis program for Hole machining CFRP was compared with the experiments.