• Fire Science and Engineering
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• v.27 no.6
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• pp.50-56
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• 2013

The radiation effects on the auto-ignition and extinction characteristics of a non-premixed fuel-air counterflow field were numerically investigated. A detailed reaction mechanism of GRI-v3.0 was used for the calculation of chemical reactions and the optically-thin radiation model was adopted in the simulations. The flame-controlling continuation method was also used in the simulation to predict the auto-ignition point and extinction limits precisely. As a result, it was found that the maximum H radical concentration, $(Y_H)_{max}$, rather than the maximum temperature was suitable to understand the ignition and extinction behaviors. S-, C- and O-curves, which were well known from the previous theory, were identified by investigating the $(Y_H)_{max}$. The radiative heat loss fraction ($f_r$) and spatially-integrated heat release rate (IHRR) were introduced to grasp each extinction mechanism. It was also found that the $f_r$ was the highest at the radiative extinction limit. At the flame stretch extinction limit, the flame was extinguished due to the conductive heat loss which attributed to the high strain rate although the heat release rate was the highest. The radiation affected on the radiative extinction limit and auto-ignition point considerably, however the effect on the flame stretch extinction limit was negligible. A stable flame regime defined by the region between each extinction limit became wide with increasing the fuel temperature.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.83-90
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• 2011

Priming refers to the incidental activation of knowledge structures, such as trait concepts and stereotypes, by the current situational context. Many studies have shown that the recent use of a trait construct or stereotype, even in an earlier or unrelated situation, carries over for a time to exert an unintended, passive influence on the interpretation of behavior. Recent researches have shown that attitudes and other affective reaction can be triggered automatically by the mere presence of relevant objects and events. So assuming that behavioral responses to fragrance are also represented mentally, they should also be capable of becoming automatically activated, by the same principles that govern the development of automaticity of other representations. On the basis of this theory, this study examined the effect of fragrance on the quality of cosmetic products.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.175-179
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• 1992

Generally speaking, natural gas possesses several characteristics that make it desirable as an engine fuel : for example (1) lower production cost, (2) abundant commodity and (3) cleaner energy source than gasoline. Due to the physical characteristics of natural gas, the volumetric efficiency and flame speed of a natural gas engine are lower than those of a gasoline engine, which results in a power loss of 10-20% when compared to a convensional gasoline engine. This paper describes the results of a research to improve the performance of a natural gas engine through the modification and controls of air/fuel ratio, spark timing advance and supercharging effect by forced air supply method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.3
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• pp.569-577
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• 1992

The effect of combustion promotion in a constant volume combustion chamber with sub- chamber located in the vicinity of spark plug, was analyzed for variables such as sub- chamber volume and diameter of orifice, and was also compared and evaluated with that of the chamber with sub-chamber which spark plug was located in the sub-chamber. Consequently, it was shown that decrease of duration of combustion in the latter case was larger than in the former case, but comparing by rate of overall combustion promotion that duration of combustion and pressure were both considered, the optimum configuration factor and the effect of combustion promotion were almost same in both cases.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.242-250
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• 2016

This study was conducted to investigate whether Stroop-related cognitive task will be affected according to the preceding affective valence factored by matchedness in response time(RT) and whether facial recognition will be indexed by specific event-related potentials(ERPs) signature in normal person as in patients suffering from affective disorder. ERPs primed by subliminal(30ms) facial stimuli were recorded when presented with four pairs of affect(positive or negative) and cognitive task(matched or mismatched) to get ERP effects(N2 and P300) in terms of its amplitude and peak latency variations. Behavioral response analysis based on RTs confirmed that subliminal affective stimuli primed the target processing in all affective condition except for the neutral stimulus. Additional results for the ERPs performed in the negative affect with mismatched condition reached significance of emotional-face specificity named N2 showing more amplitude and delayed peak latency compared to the positive counterpart. Furthermore the condition shows more positive amplitude and earlier peak latency of P300 effect denoting cognitive closure than the corresponding positive affect condition. These results are suggested to reflect that negative affect stimulus in subliminal level is automatically inhibited such that this effect had influence on accelerating detection of the affect and facilitating response allowing adequate reallocation of attentional resources. The functional and cognitive significance with these findings was implied in terms of subliminal effect and affect-related recognition modulating the cognitive tasks.

• Journal of Digital Convergence
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• v.18 no.5
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• pp.411-416
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• 2020

This study is an empirical study to see if the existing media effects have an effect on the perception of the audience in the media such as newspapers, TV, movies, etc., and whether the viewing of YouTube, an internet-based new media without gatekeeper, can affect the perception of the audience. For this study, 76 university students were divided into two groups, one group was asked to watch YouTube videos about no-buy campaign of Japanese products, and the other group was asked to watch short films for four weeks each, and then the perception and attitude of the issue were measured and analyzed through a survey. The results of the analysis showed that the audience who watched YouTube videos thought that no-buy campaign was more important than the audience who did not watch YouTube videos, and that they would participate more actively in no-buy campaign. The results of this study can be meaningful in that it confirmed the effects of the agenda setting effect and the priming effect of YouTube. It is expected that the theory of the media effect of YouTube will be established as the study on the audience effect in various fields such as politics, economy, society, culture of YouTube continues.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3819-3828
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• 2015

The present study discusses some of important issues in the word recognition such as the roles of the form(orthographic & phonologic) and semantic information by investigating the processes of Korean heteronym. The priming paradigm has been applied to see whether or not there would be facilitatory effect from form and/or semantic information. In experiment 1, orthographically-related or phonologically-related prime stimuli were presented and a lexical decision task for Korean heteronym was conducted. The same procedure was applied for the experiment 2, except the prime stimulus which was semantically-related. The results showed that orthographic and phonologic information did not influence the processing of the heteronym while semantic information facilitated its processing, suggesting that the semantic information plays an important role in the processes of the Korean heteronym.

• Science of Emotion and Sensibility
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• v.15 no.4
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• pp.575-584
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• 2012

Decades of psychological research have shown that emotion brings users various kinds of physical and psychological advantages and disadvantages. Moreover, this also impacts human decision-making. However, in spite of the weight of emotion, combined with HCI, relevant research is still insufficient. We hypothesized that the user's temporal emotion could influence the product evaluation, especially in terms of product usability. Two studies were carried out to investigate the effect of induced priming on user evaluations. In exp1, we manipulated participants' temporal emotions using positive and negative images from IAPS. In our results, we saw image priming had a statistically significant effect, with the positive condition group giving the product high ratings for usability. In exp2, emotional image manipulation was conducted with valence and arousal. As a result, we found that the variables of valence and arousal had some interaction effects. These studies have demonstrated that temporally induced emotion could affect users' emotion in different ways, in addition to influencing product evaluations.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.335-340
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• 2000

Most vehicle's exhaust emissions come from the cold transient period of the FTP-75 test. In this study, UEGI technology was developed to help close-coupled catalytic converter (CCC) reach light-off temperature within a few seconds after cold-start. In the UEGI system, unburned exhaust mixture is ignited by four glow plugs installed upstream of the catalyst. Experimental results showed that the temperature of CCC rises faster with the UEGI technology, and the CCC reaches light-off temperature earlier. Under the conditions tested, the light-off time of the baseline case was 62 seconds and that of the UEGI case was 33 seconds.

• Transactions of the Korean hydrogen and new energy society
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• v.14 no.2
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• pp.131-137
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• 2003

Backfire occurrence must be controlled for the practical use of hydrogen fueled engine. It was found from preceeding studies that crevice volume around piston rings could effect a backfire occurrence. In this study, a possible countermeasure to backfire occurrence was evaluated by using multi point ignition method around piston ring. The results showed that backfire limited equivalence ratio was increased by a little due to a enhancing effect of mixture combustion around piston crevice volume.