• Journal of Korean Society for Quality Management
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• v.21 no.2
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• pp.242-253
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• 1993

The interpretation of the reaction mechanism is significant to produce the high quality welds and understand the welding processes. This investigation is important for the design of welding consumables and the selection of welding process parameters to develop the high quality welds. The objective of this study is to investigate the effect of electrochemical reactions on the transfer of alloy elements between slag and weld metal during submerged arc welding During submerged arc welding weld metal composition is shown to be controlled by two reaction mechanisms in four reaction zones. The responsible reaction mechanisms are thermochemical and electrochemical reactions. The possible reaction sites are the melted electrode tip, the detached droplet, the hot weld pool immediately below the moving electrode, and the cooling and solidifying weld pool behind the moving electrode. The possible reactions in submerged arc welding at different zones of the process is schematically shown in Figure 1.

• Journal of the Korea Safety Management & Science
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• v.2 no.4
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• pp.187-195
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• 2000

Electrochemical promotion of the reaction rate was investigated for CO oxidation in a solid electrolyte catalytic reactor where a thin film of Pt was deposited on the yttria stabilized zirconia as an electrode as well as a catalyst. It was shown under open circuit condition that potential was a mixed potential of $O_2$exchange reaction and electrochemical reaction induced by CO. The effect of electrochemical modification on the CO oxidation rate was studied at various overpotentials and $P_{CO}$$P_{O2}$.

• Journal of the Ergonomics Society of Korea
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• v.35 no.5
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• pp.403-411
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• 2016

Objective: This study is concerned with the user interface (UI) design of touch screen based on the reaction time of Automated Teller Machine (ATM) user. Background: Adopting the touch screen technology, the ATM service has recently established a new user interface different from the existing button-type interface. Method: Experiments were conducted by simulating ATM touch screen layouts, and layouts were focused on location of menu buttons (left and right, top and bottom), number of menu buttons (8 and 12 buttons). Results: The results show that there are significant differences in correction ratio and reaction time by user groups, types of menu location, and the number of buttons. Conclusion and Applications: The results of this study can be used to provide baseline information for the interface design of ATM touch screen and the age differences in reaction time.

• Industrial Engineering and Management Systems
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• v.4 no.2
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• pp.176-183
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• 2005

The theory of signal detection has been applied to a wide range of practical situation for a long time, including sonar detection, air traffic control and so on. In general, in this theory, sensitivity parametric index d' and bias parametric index $\beta$ are used to evaluated the performance of vigilance. These indices use observer's response "hit" and "false alarm" to explain and evaluate vigilance, but not considering reaction time. However, the reaction time of detecting should be considered in measuring vigilance in some supervisory tasks such as unlimited monitoring tasks (e.g., supervisors in nuclear plant). There are some researchers have used the segments of reaction time to generate a pair of probabilities of hit and false alarm probabilities and plot the receiver operating characteristic curve. The purpose of this study was to develop a quantitative vigilance-measuring model by fuzzy sets, which combined the concepts of hit, false alarm and reaction time. The model extends two-values logic to multi-values logic by membership functions of fuzzy sets. A simulated experiment of monitoring task in nuclear plant was carried out. Results indicated that the new vigilance-measuring model is more efficient than traditional indices; the characteristics of vigilance would be realized more clearly in unlimited monitoring task.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.161-167
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• 2002

Cai-go management facility of harbor are required an expansion due to increase of cargo quantity. Design technology of Yard AGV call be possible to deal many cargo rapidly and accurately. So it is produced a profit about cal-go management. This study is presented optimum of suspension parameter for design technology Yard AGV. Model I, II are modeled about Initial of container weight, height. When the maximum stroke of suspension is 0.26m, optimum is achieved to reduce the reaction force at the minimum. Also, the reaction force is study to become stability in I second. A change of spring constant and coefficient of damper make change the reaction force and minimum reaction force appear in optimum value. All modeling and analysis are used combination. contact element of Ansys program.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.111-120
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• 2008

The combustion reaction of polypropylene was investigated using a thermogravimetric technique under an air atmosphere condition at several heating rates from 10 to $50^{\circ}C/min$. To obtain information on the kinetic parameters, the dynamic thermogravimetric analysis curve and its derivative were analyzed by a variety of analytical methods such as Kissinger, Friedman, Freeman-Carroll, Chatterjee-Conrad, Ozawa and Coats-Redfern methods. The comparative works for the kinetic results obtained from various methods should be performed to determine the kinetic parameters, because there are tremendous differences in the calculated kinetic parameters depending upon the mathematical method taken in the analysis.

• The Journal of Korean Physical Therapy
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• v.22 no.2
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• pp.7-13
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• 2010

Purpose: This study was designed to determine the correlation between faster response time and functional activities of brain regions during cognitive time management. Methods: Twelve healthy subjects participated in this experiment. Subjects performed the serial reaction time task (SRTT), which was designed by the Superlab program, during fMRI scanning. When the 'asterisk' appeared in the 4 partition spaces on the monitor, the subject had to press the correct response button as soon as possible. Results: fMRI results showed activation of the left primary sensorimotor cortex, both premotor areas, the supplementary motor area, posterior parietal cortex and cerebellum. There were significant correlations, from moderate to strong, between faster reaction time and BOLD signal intensity in activated areas. Conclusion: These results suggest that motor skill learning to be needed cognitive time management is associated with greater activation of large scale sensorimotor networks.

• Culinary science and hospitality research
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• v.23 no.5
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• pp.159-168
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• 2017

This study was conducted to investigate the effects of high class korean restaurants' servicescape on customers' emotional response and intention to revisit. This study also examined the relationship among emotional and cognitive reactions and intention to revisit. A total of 216 questionnaires were analyzed using the factor analysis, reliability test, and structural equation modeling analysis. The results revealed that space, aesthetics and comfortableness were positively related to emotional reaction, and convenience and cleanliness were related to cognitive reaction. This study also found that intention to revisit was positively related to emotional and cognitive reactions. Moreover, it was found that think was positively related to emotional reaction, and feel, think, act and the related were positively related to cognitive reaction. Finally, cognitive reaction was positively related to revisit. The results of the study suggested that high-class Korean restaurant marketers should introduce or strengthen servicescape, brand reputation and experiences, which increased brand attitude or revisit.

• Journal of the Korea Safety Management & Science
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• v.1 no.1
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• pp.29-39
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• 1999

Human sensibility ergonomics is the technique that qualities man's sensibility, measures and evaluates it Quantitatively and makes man's life comfortable, safe and delightful by applying it to products or environmental projects. This study consider the sensibility factor of Sasang constitutional medicine, five elemental properties, and Biorhythm in terms of human sensibility ergonomics. And this study measure reaction-time dependent on a temperament or a state and evaluate the differences of reaction-times objectively with the comparison and analysis using the ANOVA. We can harness it for job design.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.110-115
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• 2007

In this study we investigated the volatile compounds that are generated in sesame and contribute to its characteristic flavor. Different reaction systems were used to examine how certain amino acids influenced flavor profiles, and also to evaluate the effects of sugar types on the distribution of those volatile compounds. The volatiles that were generated in each reaction system were selectively isolated and analyzed by gas chromatography and gas chromatography-mass spectrometry, respectively. Among the 20 identified compounds, nitrogen-containing alkylpyrazines were found to be the predominant volatiles. The alkylpyrazine amounts varied across the different model systems, with the total yield being highest in the arginine reaction mixture, followed by the alanine, serine, and lysine mixtures. In general, fructose generated the most extensive amount of volatiles compared to glucose and sucrose. However, the yield of specific flavor compounds varied according to the type of sugar used. Finally, the results clearly showed that a reaction temperature of $135^{\circ}C$ and a reaction time of 20 min generated the highest amount of volatile compounds.