• Journal of Power System Engineering
• /
• v.18 no.6
• /
• pp.58-63
• /
• 2014

This paper deals with the effects of counterpart materials on the wear behavior of thermally sprayed STS316 coatings. STS316 powders were flame-sprayed onto a carbon steel substrate. Dry sliding wear tests were performed using the applied loads of 15 N. AISI52100, $Al_2O_3$, $ZrO_2$ and $Si_3N_4$ balls were used as counterpart materials. Wear behavior of STS316 coatings against different counterpart materials were studied using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDS). The results show that the wear behavior of thermally sprayed STS316 coatings strongly depends on the type of counterpart material. Dominant wear mechanism was similar for all studied materials as failure of adhesion film except for Si3N4 used as counterpart material. In the case of Si3N4 used as counterpart material, dominant wear mechanism was abrasion.

• Journal of Powder Materials
• /
• v.13 no.6 s.59
• /
• pp.450-454
• /
• 2006

Wear of steel plate was measured during unlubricated sliding against TiC composites. These composites consist of round TiC grains and steel matrix. TiC grain itself exhibits low surface roughness and round shape, which does not bring its counterpart into severe damage from friction. In our work a classical experimental design was applied to find out a dominant factor in counterpart wear. The analysis of the data showed that only the applied load has a significant effect on the counterpart wear. Wear rate of counterpart increased non-linearly with applied load. Amount of wear was discrepant from expectation of being in proportion to the load by analogy with friction force. Our experimental result from treating matrix variously revealed bimodal wear behavior between the composites and counterpart where a mode seems to result from the special lubricant characteristic of TiC grains, and the other is caused by metal-to-metal contact. The two wear mechanisms were discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.47 no.3
• /
• pp.267-272
• /
• 2011

The behavior of abrasive wear on counterpart roughness of glass fiber reinforcement polyurethane resin (GF/PUR) composites were investigated at ambient temperature by pin-on-disc friction test. The friction coefficient, cumulative wear volume and surface roughness of these materials against SiC abrasive paper were determined experimentally. The major failure mechanisms were lapping layers, ploughing, delamination, deformation of resin and cracking by scanning electric microscopy (SEM) photograph of the tested surface. As increasing the counterpart roughness the GF/PUR composites indicated higher friction coefficient. The surface roughness of the GF/PUR composites was increased as the sliding velocity was higher and the counterpart roughness was rougher in wear test.

• Human Ecology Research
• /
• v.54 no.1
• /
• pp.45-56
• /
• 2016

This study investigates: (1) children's proactive aggression according to age and the emotional condition of the counterpart child, (2) if children's intention attribution, emotional attribution (victim and perpetrator) and language ability influences proactive aggression according to age and the emotional condition of the counterpart child. The subjects were 68 3-year-old and 70 5-year-old children. Each child was individually interviewed with picture cards. Collected data were coded and analyzed in SPSS with frequencies, percentiles, means, standard deviations, repeated measures analysis of variance (ANOVA), t -tests, Pearson correlations and multiple linear regression. The results showed that 3-year-old children showed more proactive aggression and physical aggression than 5-year-old children. They showed more proactive aggression when counterpart child was in a happy condition than in a fear condition. Intention attribution, emotional attribution, and language ability partially affected a children's proactive aggression according to age and the emotional condition of the counterpart child. This study has practical implications for teachers in regards to children's proactive aggressive behavior at child care centers. Teachers use specific to develop advantages as the basis for developing aggression prevention programs that consider emotional and cognitive factors.

• Journal of Power System Engineering
• /
• v.13 no.6
• /
• pp.123-128
• /
• 2009

The effects of temperature and initial crack length on the impact fracture behavior for the side plate material of FRP ship were investigated. And the effects of the counterpart roughness and sliding distance on the volumetric wear of same material were investigated as well. Impact fracture toughness of GF/PE composites displayed maximum value when the temperature of specimen is room temperature and $50^{\circ}C$, and with decreasing the temperature of specimen, impact fracture toughness decreased. Impact fracture energy of GF/EP composites decreased with increasing the initial crack length of specimen, and this value decreased rapidly when the temperature of specimen is lowest, $-25^{\circ}C$. It is believed that sensitivity of notch on impact fracture energy were increased with decreasing the temperature of specimen. With increasing the sliding distance, the transition sliding distance, which displayed different aspect on the friction coefficient and the volumetric wear loss, were found out. Counterpart roughness had a big influence on the wear rate at running in period, however the effect of counterpart roughness became smaller with sliding speed increase in. Volumetric wear loss were increased with increasing the applied load and the counterpart roughness.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.05a
• /
• pp.390-394
• /
• 2004

This is the study on dry sliding wear behavior of unidirectional carbon fiber reinforced epoxy matrix composite at ambient temperature. The wear rates and friction coefficients against the stainless steel counterpart specularly processed were experimentally determined and the resulting wear mechanisms were microscopically observed. Three principal sliding directions relative to the dominant fiber orientation in the composite were selected. Wren sliding took place against smooth and hard counterpart, the highest wear resistance and the lowest friction coefficient were observed in the antiparallel direction. When the velocity between the composite and the counterpart went up, the wear rate increased. The fiber destruction and cracking caused fiber bending on the contact surface, which was discovered to be dominant wear mechanism.

• The Bulletin of The Korean Astronomical Society
• /
• v.44 no.1
• /
• pp.62.3-62.3
• /
• 2019

After first identification of electromagnetic counterpart of gravitational wave source (GW170817), era of multi-messenger astronomy has begun. For specifying coordinate, magnitude, and host galaxy information, optical follow-up observation of GW source becomes important. With following engineering run and O3 run of LIGO and VIRGO starting in March 2019, we present searching strategy for optical counterpart of GW source using KMTNet. 24 hours monitoring system and large field of view (4 square-degree) of KMTNet are advantage to discover a transient like GW event. By performing tiling observation of high probability area in GW localization map, we expect to observe early light-curve of GW optical counterpart. After identification, follow-up observation with various KMTNet bands and other telescopes like Gemini and UKIRT will also be performed. We will study collision mechanism, progenitor, and characteristics of host galaxy using observation data of GW source.

• Korean Journal of Child Studies
• /
• v.38 no.1
• /
• pp.127-138
• /
• 2017

Objective: This study examined differences in preschoolers' prosocial decision-making, emotion understanding in prosocial dilemmas based on the age and emotional conditions of a counterpart child, and the effects of emotion understanding on preschoolers' prosocial decision-making. Methods: The participants were 114 children (35 3-year-olds, 39 4-year-olds, and 40 5-year-olds). Each child was presented individually with prosocial dilemma tasks and was asked to make decisions and understand emotions (in prosocial and desire-fulfilled situations) based on the emotional conditions of a counterpart child. Results: First, the 4- and 5-year-olds showed more prosocial decision-making in prosocial dilemmas than the 3-year-olds. Prosocial decision-making was significantly lower when the counterpart child was angry, rather than neutral or sadness. Second, in prosocial situations, the 5-year-olds displayed higher positive emotion understanding scores than the 3-year-olds, And in desire-fulfilled situations, the 3-year-olds showed positive emotion understanding, whereas the 4- and 5-year-olds showed negative emotion understanding. Finally, children were more inclined toward prosocial decision-making when they showed higher emotion understanding in prosocial situations, lower emotion understanding in desire-fulfilled situations, and greater age. These were equal to all emotional conditions of the counterpart child. Conclusion: These results suggest that emotion understanding is an important component of social cognition, which effects preschoolers' prosocial decision-making.

• Bulletin of the Korean Mathematical Society
• /
• v.43 no.1
• /
• pp.27-41
• /
• 2006

A counterpart of the famous Bessel's inequality for orthornormal families in real or complex inner product spaces is given. Applications for some Gruss type inequalities are also provided.

• Communications of the Korean Mathematical Society
• /
• v.39 no.1
• /
• pp.117-125
• /
• 2024

In this paper, our focus is on exploring value sharing problems related to a transcendental entire function f and its associated differential-difference polynomials. We aim to establish some results which are related to differential-difference counterpart of the Brück conjecture.