• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.1
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• pp.79-92
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• 1992

This is analyzed using the finite element method which is appling excellent isoparametric curve element in the aspect of large usages of dynamic responses in which is regarding geometric and material nonlinear of a large scale shell structure of an airplane, a submarine, a ship, and an ocean structure. The solution of dynamic equations is got by direct integration method using time-stepping procedure and regarding Central Difference Method of the both solutions. But because formal matrix factorization is not necessary in each time step and it does not take less time to compute relatively, this method must be regarded very few time steps on the condition. Axisymmatric shell problems are inspected using 8 node Isoparametric element in this paper. Partial axisymmatric spherical shell is used as a model to analyze axisymmatric nonlinear dynamic behavior regarding. Total Lagrangian formulation in geometric nonlinear behavior and elastio-viscoplastic in material nonlinear behavior.

• Journal of the Korean Society of Safety
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• v.15 no.2
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• pp.8-12
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• 2000

The fatigue crack propagation tests were performed in triangular and holding-time stress waveforms at $650^{\circ}C$. The behavior of fatigue crack propagation was investigated according to waveform. The analysis of high temperature fatigue crack propagation by the stress intensity factor range ${\Delta}K$, elastic fracture mechanics parameter, was not available. The behaviors of high temperature fatigue crack propagation by the J-integral(${\Delta}J_f$, J' and ${\Delta}J_c$), elasto-plastic fracture mechanics parameter, were investigated in a number of stress waveforms. The fast-fast waveform exhibited cycle-dependent(fatigue type), the slow-fast and the hold time with 500sec waveforms appear to be time-dependent(creep type) and the fast-slow and the hold time with 5, 25sec waveforms exhibited conbined behavior of both types(fatigue-creep conbined type).

• Journal of Family Resource Management and Policy Review
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• v.6 no.2
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• pp.15-29
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• 2002

The purpose of this study explores the meaning of shopping and shopping behavior of consumer under the perception of time pressure. In this study, qualitative methods such as participation observation, depth interview, focus group interview were used. The major findings are as follows : First, consumer under the perception of time pressure defined shopping is mainly' grocery purchasing'. Second, they go shopping on weekend, in familiar store and buy the same kind of goods. Like this, their shopping patterns appear fixed type. Third, this study ascertained proposed time management strategies applied to shopping. Finally, a place of residence, driving or not, house helper, children and standard of family influence on consumer's shopping behavior additionally.

• Journal of Information Display
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• v.11 no.2
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• pp.57-62
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• 2010

A method of characterizing time-sequential stereoscopic 3D displays based on the measurement of the temporal behavior of the systems vs. the grey levels is proposed. An Nvidia 3D vision kit with a 3D-ready SAMSUNG 2233RZ LCD display is characterized in the paper. OPTISCOPE SA especially designed for the precise measurements of the luminance and temporal behavior of LCD displays was used. The transmittance and response time of the shutter glasses was first evaluated. Then the grey-to-grey response times of the display were measured. The 2D and 3D behaviors of the display were then compared. Finally, the temporal behavior of the complete system was modeled, and the grey-level variations on one view were deduced as a function of the synchronization and level of the other eye. The main sources of imperfection were identified and quantified, and a full computation of the system performances was done.

• Nuclear Engineering and Technology
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• v.43 no.1
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• pp.1-6
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• 2011

The behavior of the non-equilibrium grain boundary segregation of boron in low carbon steel was studied through a particle tracking autoradiography. The behavior of the non-equilibrium grain boundary segregation of boron during continuous cooling was compared with the isothermal kinetics of the non-equilibrium grain boundary segregation of boron at the holding temperature using an effective time method. On the basis of the experiments, the cooling rate dependence of the non-equilibrium segregation of boron was explained using the time dependence of the non-equilibrium segregation of boron in low carbon steel. The experimental observations for the cooling rate dependence of the grain boundary segregation of boron are in good agreement with the time dependence of the grain boundary segregation of boron. The mechanisms of the non-equilibrium segregation of boron during cooling in low carbon steel are also discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.22
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• pp.71-78
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• 1990

Some problems to assess the safety of automated man-machine system are studied in many ways. The difficulty occurred in this system is the vagueness of human behavior. Fuzzy set theory is used to assess the human behavior in safety analysis. The unsafe behavior listed top 10 in accident statistics would be explained as the factors of human vagueness. Three cases are considered, which consist of man-machine system as man-man, man-machine, machine-machine types. For the design of safe task, using characteristics of work performance, each motion cycle time is required to know the rate of learning. Approach of human behavior to the standard motion means more safe motion. It is important to design the works as to minimize the time performance to the standard motion's, which utilize the control of risk potential with easy. In that process, use of fuzzy set theory is appropriate to analyze the human behavior to identify its vagueness.

• International Journal of Human Ecology
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• v.17 no.1
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• pp.27-37
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• 2016

This study was to understand associated factors with frequent exposure to Internet pornography among Korean adolescents. We used data (N = 45,783) from the 2012 Korea Youth Risk Behavior Web-based Survey to examine demographics, family environmental variables, Internet use time, mental health indicators, sexual behavior, and delinquency among Korean adolescents identified as frequent users of Internet pornography. Multiple logistic regression analysis revealed that frequent users of Internet pornography were more likely to be older males with differences in living arrangements and perceived economic status of the family. They were heavy Internet users with mental health issues, such as a higher likelihood of sadness, suicidal ideation, suicide attempts, high stress, and a lower likelihood of feeling happiness. Their higher probability of exploratory (OR =1.79-4.60), and high-risk sexual behavior (OR = 2.20-7.46), and other delinquencies (OR = 1.74-7.68) requires more attention from public health professionals.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.6 no.4
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• pp.314-320
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• 2006

Navigation in environments that are densely cluttered with obstacles is still a challenge for Autonomous Ground Vehicles (AGVs), especially when the configuration of obstacles is not known a priori. Reactive local navigation schemes that tightly couple the robot actions to the sensor information have proved to be effective in these environments, and because of the environmental uncertainties, STSF(Space and Time Sensor Fusion)-based fuzzy behavior systems have been proposed. Realization of autonomous behavior in mobile robots, using STSF control based on spatial data fusion, requires formulation of rules which are collectively responsible for necessary levels of intelligence. This collection of rules can be conveniently decomposed and efficiently implemented as a hierarchy of fuzzy-behaviors. This paper describes how this can be done using a behavior-based architecture. The approach is motivated by ethological models which suggest hierarchical organizations of behavior. Experimental results show that the proposed method can smoothly and effectively guide a robot through cluttered environments such as dense forests.

• Human Ecology Research
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• v.56 no.6
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• pp.541-553
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• 2018

This study examined the influences of infants' age for the first use of smart devices and the amount of time to use them on the externalizing problem behavior as well as investigated whether maternal managing behavior (setting rules on accessing smart devices and monitoring their child's use of smart devices) had moderating effects. The study participants consisted of 521 three to six year old infants (235 boys and 286 girls). The data were analyzed by means of descriptive statistics and a hierarchical regression. The results of this study indicated that the age at first use of smart devices and maternal managing behavior had significant effects on the externalizing problem behavior of infants. The earlier the infants first used smart devices, the higher the level of externalizing problem behavior. Externalizing problem behavior was also found to be higher when the mothers showed no managing behavior. Second, maternal managing behavior moderated the relation between the age at first use of smart devices and the externalizing problem behavior of infants. The effects of the age at first use of smart devices on the externalizing problem behavior of infants were greater when the mothers did not set rules regarding the use of smart devices and did not supervise children when using smart devices.

• Journal of Families and Better Life
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• v.17 no.4
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• pp.119-132
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• 1999

This study focused on recycling behavior and related variables. Specifically it aims 1) to investigate the level of recycling attitudes and behaviors 2) to find out variables related to recycling behavior, Data were collected with questionaire from 248 wives in Kwangju city. The results can be summerized as follows: The sorting behavior of waste was higher than median but active recycling behavior was lower than median. The recycling behavior was facilitated by wives' high age lower education level apartment dwelling and part-time job. In addition to motivate the recycling behaviors various implications discussed.