• 대한안전경영과학회지
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• 제12권4호
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• pp.31-39
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• 2010

The purpose of this study was to examine the effects of stress response on safety behavior and to explore moderating effect of safety climate between stress response and safety behavior. 224 workers were asked to respond to the questionnaires that measured various demographic variables, stress response, safety climates and safety behaviors. A hierarchical regression was conducted to identify variables that had significant relationships with safety behavior and to examine moderating effect of safety climate between stress response and safety behavior. Results indicated that the depression response significantly predicted safety behavior. It was found that the safety climate was also a significant predictor for safety behavior. In addition, safety climate had a moderating effect on the relation between depression and anger responses and safety behavior.

• East Asian Economic Review
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• 제19권1호
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• pp.3-38
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• 2015

Fama's (1984) volatility relations show that the risk premium in foreign exchange markets is more volatile than, and is negatively correlated with the expected rate of depreciation. This paper studies these relations from the perspective of goods markets frictions. Using a sticky-price general equilibrium model, we show that near-random walk behaviors of both exchange rates and consumption, in response to monetary shocks, can be derived endogenously. Based on this approach, the paper provides quantitative results on Fama's volatility relations.

• Journal of Power Electronics
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• 제17권2호
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• pp.501-513
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• 2017

The fundamental small-signal modeling of lithium-ion (Li-ion) batteries and a parameter evaluation approach are investigated in this study to describe the dynamic behaviors of small signals accurately. The main contributions of the study are as follows. 1) The operational principle of the small signals of Li-ion batteries is revealed to prove that the sinusoidal voltage response of a Li-ion battery is a result of a sinusoidal current stimulation of an AC small signals. 2) Three small-signal measurement conditions, namely stability, causality, and linearity, are proved mathematically proven to ensure the validity of the frequency response of the experimental data. 3) Based on the internal structure and electrochemical operational mechanism of the battery, an AC small-signal model is established to depict its dynamic behaviors. 4) A classical least-squares curve fitting for experimental data, referred as Levy's method, are introduced and developed to identify small-signal model parameters. Experimental and simulation results show that the measured frequency response data fit well within reading accuracy of the simulated results; moreover, the small-signal parameters identified by Levy's method are remarkably close to the measured parameters. Although the fundamental and parameter evaluation approaches are discussed for Li-ion batteries, they are expected to be applicable for other batteries.

• 한국식품영양학회지
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• 제29권1호
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• pp.104-114
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• 2016

In this study, we investigated protection motivation and behavioral intention to prevent serious illnesses related to excessive sodium intake among the university students in Gyeongnam and Busan. Within the protection motivation theory (PMT) framework, a survey questionnaire was developed to measure participants' perceptions on the severity of and the vulnerability to the threat of serious diseases due to the high sodium intake as well as the effectiveness of preventive measures (response efficacy), and the ability to perform them (self-efficacy) along with their willingness to follow recommendations (behavioral intention). Data was collected in June 2015. Study participants were divided into either low (n=117) or high (n=177) sodium intake behavior groups based on their current behaviors. Exploratory factor analysis was performed to measure construct validity and Cronbach's alpha was calculated to check reliability of measurement items. The high sodium intake behavior group perceived higher vulnerability than the low sodium intake behavior group among four PMT factors. Differences of the other three factors were not significant between the two groups. The results of hierarchical regression analysis indicated that self-efficacy and response efficacy affected behavioral intention of high sodium intake behavior among students. Hence, development of strategies to increase self-efficacy and response efficacy are strongly recommended.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권7호
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• pp.388-393
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• 2000

Hydrogen-sensing behaviors of Pd- and Pt-SiC Schottky diodes, fabricated on the same SiC substrate, have been systematically compared and analyzed as a function of hydrogen concentration and temperature by I-V and$\DeltaI-t$ methods under steady-state and transient conditions. The effects of hydrogen adsorption on the device parameters such as the barrier height are investigated. The significant differences in their hydrogen sensing characteristics have been examined in terms of sensitivity limit, linearity of response, response rate, and response time. For the investigated temperature range, Pd-SiC Schottky diode shows better performance for H2 detection than Pt-SiC Schottky diode under the same testing conditions. The physical and chemical mechanisms responsible for hydrogen detection are discussed. Analysis of the steady-state reaction kinetics using I-V method confirmed that the atomistic hydrogen process is responsible for the barrier height change in the diodes.

• Structural Engineering and Mechanics
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• 제84권5호
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• pp.675-684
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• 2022

The conventional single-degree-of-freedom (SDOF) system is appropriate for dynamic response analysis of paneltype structures without an opening. However, the typical building structures usually have four-sided fixed walls having an opening. Therefore, it may induce a considerable error when dynamic responses are estimated based on the conventional SDOF system, since the SDOF system cannot consider the effect of an opening during the SDOF analysis. For this reason, this study proposes a new SDOF system to consider the effect of an opening by adjusting its load-mass factor. The load-mass factor can be modified based on the assumption that the behaviors of the four-sided fixed wall with an opening is very similar to the behaviors of the same size wall without an opening, when the uniformly distributed blast loaded area is identical. In order to confirm a feasibility of the proposed SDOF system, a series of numerical simulations were carried out for the four-sided fixed reinforced concrete (RC) wall under a blast load. The dynamic responses estimated from the proposed SDOF system and the conventional SDOF system were compared with the dynamic responses evaluated from the finite element (FE) analysis. Especially, for the maximum dynamic responses except for 50% opening case, the proposed SDOF system had about 1.1% to 25.7% normalized errors while the conventional SDOF system had about 4.1% to 49.1% normalized errors.

• 한국자동차공학회논문집
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• 제10권4호
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• pp.122-128
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• 2002

In this paper dynamic responses of an engine, which is supported by hydraulic mount, to throttle tip-in/Tip out are analyzed. Because the hydraulic mounts have non-linearity that the characteristics of stiffness and damping vary with frequencies, it is difficult to analyze the dynamic behavior of an engine using general integral algorithms. Convolution integral and relationship between unit impulse response functions and frequency response functions are therefore used to simulate the transient behaviors of an engine indirectly. In time domain, impulse response functions are calculated by two-side discrete inverse courier transform of frequency response function achieved by laplace transform of equations of motion. Considering the fact that the shapes of behavior of an engine simulated by the proposed method are in good agreement with test results, it is confirmed that the proposed method is very effective for the analysis of transient response to throttle tip-in/out of an engine with hydraulic mounts.

• 대한간호학회지
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• 제39권4호
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• pp.562-573
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• 2009

Purpose: The purpose of this study was to identify the effects on the cognitive function, Activities of Daily Living (ADL), mood, social behaviors, and problematic behaviors of robot pet-assisted program for elderly people with dementia. Methods: This study was a nonequivalent control group pretest-posttest design. The participants were 32 elders with dementia. Seventeen were assigned to the experimental group and 15 to the control group. The intervention was conducted twicea week for 6 weeks. Results: 1) After the program, cognitive function, ADL, and social behaviors did not show significant differences. 2) After the program, mood of experimental group was significantly better than that of the control group. 3) After the program, problematic behaviors of the experimental group were significantly more diminished than those of control group. 4) As a result of analyzing the response, robot pet-assisted program was effective such as inducing a positive emotional state and increasing communication and interaction. Conclusion: The robot pet-assisted program was effective in changing the mood and diminishing problematic behaviors and had positive effects such as increasing communication and interaction for elders with dementia. Therefore, this program should be considered as a positive program for physical and emotional support for elders with dementia.

• Smart Structures and Systems
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• 제12권5호
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• pp.523-545
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• 2013

Piezoelectric and dielectric behaviors of a piezoceramic patch adhesively centered on a carbon composite plate are identified using a robust multi-objective optimization procedure. For this purpose, the patch piezoelectric stress coupling and blocked dielectric constants are automatically evaluated for a wide frequency range and for the different identifiable behaviors. Latters' symmetry conditions are coded in the design plans serving for response surface methodology-based sensitivity analysis and meta-modeling. The identified constants result from the measured and computed open-circuit frequencies deviations minimization by a genetic algorithm that uses meta-model estimated frequencies. Present investigations show that the bonded piezoceramic patch has effective three-dimensional (3D) orthotropic piezoelectric and dielectric behaviors. Besides, the sensitivity analysis indicates that four constants, from eight, dominate the 3D orthotropic behavior, and that the analyses can be reduced to the electromechanically coupled modes only; therefore, in this case, and if only the dominated parameters are optimized while the others keep their nominal values, the resulting piezoelectric and dielectric behaviors are found to be transverse-isotropic. These results can help designing piezoceramics smart composites for various applications like noise, vibration, shape, and health control.

• Fashion, Industry and Education
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• 제15권2호
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• pp.36-52
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• 2017

In this study, we tried to understand preschooler clothing trends and identify the purchase behaviors of various consumers, such as grandparents, aunts, uncles, and parents, who are the main consumers of the preschooler clothing market. We conducted in-depth interviews with consumers who were interested in preschooler clothing, purchased it frequently, and bought preschooler clothing within the last three months. Their purchase motivations and purchase behaviors were analyzed through exploratory and inductive analysis. The analysis was conducted by integrating categories into one process centered on core categories through open coding, axial coding, and selective coding. The results of this study included that 1) a variety of clothing purchase behaviors appeared as a central phenomenon, 2) the causal conditions that contributed to this phenomenon were the buyers' childcare experiences, purchase experiences, the personal consumption values of individuals, and income levels, 3) in response to the central phenomenon, the parents' action/interaction strategies were acceptance and rejection of purchased clothing, 4) contextual and Intervening conditions affecting action/interaction strategy were family environment changes, the VIB (Very Important Baby) phenomenon, parents' clothing involvement, and the relationship with the buyers, and acceptance by the users, and 5) as a result of the strategy expressed as acceptance and rejection, various clothing behaviors emerged. In this study, we identified that there are various influencers, apart from parents, involved in children's clothing consumption. Therefore, we need to keep in mind that various purchase behaviors and clothing trends that appear during one's childhood may affect the individual's clothing behavior in the future.