• Journal of Power Electronics
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• v.5 no.4
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• pp.264-271
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• 2005

A new modified trapezoidal modulating signal for a pulse width modulation (PWM) inverter suitable for a permanent magnet synchronous motor (PMSM) drive is proposed in this paper. A new modulating signal for the PMSM drive is determined by the characteristic torque ripple of the motor with various electro-motive force (EMF). The proposed modulating signal is able to decrease the torque ripple even if the motor has sinusoidal EMF or non-sinusoidal EMF. By using the proposed modulating signal, the system reduced the torque ripple as well as achieved the effective utilization of the DC supply voltage for the inverter. Many improvements are accomplished by the PWM strategy adapting the modified trapezoidal modulating signal without a change in hardware.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.7 no.2
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• pp.73-79
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• 1978

This paper presents the experimental study on the design conditions of pressure between booster ejector and air ejector in the steam-jet water-vapour refrigeration system. In this experiment, the motive steam of booster ejector and ai. ejector was dry saturated from 6 ata to 8 ata and flash chamber pressure were about $10\∼540mmHg$ higher than mixing section in booster ejector. The investigation of air on the pressure of booster ejector was performed by changing the condenser pressure. The experimental results show that flash chamber vacuum and condenser pressure of steam-jet refrigeration cycle increased in accordance with the increase of motive steam Pressure. Among the several nozzle sires tested, No.4 nozzle were best in term of evaporator vacuum under the constant operating conditions of air ejector in condenser.

• Magazine of the Korea Concrete Institute
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• v.19 no.4
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• pp.16-19
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• 2007

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2012.05a
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• pp.138-139
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• 2012

• Proceedings of the Korean Magnestics Society Conference
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• 2011.12a
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• pp.105-105
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• 2011

• Journal of the Korean Home Economics Association
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• v.46 no.6
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• pp.89-100
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• 2008

The purpose of this study was to provide basic data for the familial voluntary service of the Healthy Family Center and then verify the effectiveness of its application in order to improve family healthy through a familial voluntary service. Study subjects were both volunteers who belonged to family volunteer corps of 12 Healthy Family Centers. Collected data was analyzed SPSS WIN 12.0 program. The results were as followed. First, a 54.1% of subjects is taking part in a familial voluntary service, while a 45.9% of them is not. Their positive intention of future participation is a 77.4%. The period of participation is from 6 months to two years. The frequency of participation is once or twice a month, and the length of activities per participation is for 3 hours. They have taken part in the service with a variety of public relations, and their motive of participation is by and large selfish. Second, as for the influence of participation in a familial voluntary service upon family healthy, the family healthy of participant group is higher in all the four sub-variables of family healthy than that of other groups. The group of which frequency of participation is once a week is better in family communication than the group of which frequency of participation is once or twice per month. The group of which motive of participation is altruistic is higher in sharing a value system among families than the group of which motive of participation is selfish.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.799-810
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• 2017

In this study, to raise the scientific literacy for students, the teaching and learning program was developed by applying the Circle Map. The purpose of this study was to find out the Effect of Elementary Science Teaching Program with Circle Map on Learning Motive and Learning Achievement. To this end, the 6th grade classroom of A-elementary school located in Jeju-city was selected the experimental group (25 patients). And the other 6th grade classroom in the same school was selected to the comparative group (25 patients). The experimental group was conducted applying the Circle Map. Comparison group has been conducted lesson program in accordance with the general science class teacher guide. Was through a pre-test of science learning motivation and academic achievement level can be assumed in the same group. After completing the experimental treatment by conducting a post-mortem examination was statistically validated. In this study, the following conclusions were obtained. First, elementary science class which applied Circle Map had the effect of to improve the scientific motivation(p <.05). In particular, association in the experimental group were higher than the scores of the comparative group, the difference was significant. Second, the Circle Map applied to elementary science class had a significant effect on improving science achievement. The experimental group which applied Circle Map was higher than the comparative group in science achievement post-test comparison. Between the groups showed a significant difference between the two groups(p <.05). The above findings, Elementary science class which applied Circle Map can be concluded to be effective in science and science achievement motivation. Therefore, applying the Circle Map of elementary science class could be useful in science teaching and learning methods. In addition, when it is determined through the previous study, applying the Circle Map classes will be able to derive a meaningful learning also subjected to a number of fields and areas.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.103-117
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• 2010

The purpose of this study was broken down into four sections. First, this study identified both single workers' lifestyles and their motives for going to restaurants. The study classified the consumers and then confirmed the attributes of selection that the consumers considered important when eating out at family restaurants. Second, the study analyzed the consumers' lifestyles, motives for going to restaurants (user motive), and the attributes of selection for the restaurant. Third, the study analyzed how the attributes of selection toward the family restaurant affect the consumer's satisfaction and the consumer's intention of revisiting the restaurant. Fourth, the study analyzed how consumer satisfaction affects the intention to revisit the family restaurant. After the execution of the aforementioned four steps, the study was successful in meeting its purpose: to provide information to enhance the satisfaction of the consumer and to provide foundation material for consumer policy. In regards to the analytical method, this study performed a Frequency Analysis, Factor Analysis, Reliability Analysis, Cluster Analysis, ANOVA Analysis, and Multiple Regression Analysis. The analytical results from the study are as follows. Lifestyle was categorized into 4 factors and 4 clusters. User motive was grouped into 3 factors and 4 clusters. The attributes of selection for family restaurants were categorized into 4 factors. Based on the lifestyle cluster, the attributes of selection for family restaurants showed a statistically significant difference. In addition, based on the cluster of user motive, the attributes of selection for family restaurants showed a statistically significant difference. Lastly, the attributes of selection for family restaurants were found to affect both the intention of revisiting the restaurant and consumer satisfaction after the consumers used the restaurants.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1185-1191
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• 2008

The core design technology for the multi-effect desalination plant using the thermo compressor (MED-TVC) was investigated by the performance test of multi effect desalination plant in this paper. The final G.O.R (gain of output ratio) of MED-TVC type desalination plant is strongly affected by the performance of thermo-vapor compressor. The present experiments for the desalinating capacity and G.O.R were obtained for the range of the motive steam pressure, 266.0, 250.0, 230.0 and 200.0 kPa. And as a practical problem, to investigate the influence of the sea water temperature to the G.O.R, the inlet steam temperature of the suction water vapor was changed in the range of $311.2{\sim}324.2$ K in the present experiment. Through the experiments, the maximum value of G.O.R was 8.5 at the condition of the motive steam pressure, 136.0 kPa and the minimum value of G.O.R was 8.1 at the condition of the motive steam pressure, 266.0 kPa. And it was confirmed that the range of desalination capacity was $355.2{\sim}264.0$ ton/day in the normal operation condition.

• Korean Journal of Psychosomatic Medicine
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• v.4 no.2
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• pp.182-197
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• 1996

For the purpose of examining the relationship between smoking, perceived stress and vulnerability factors, and furthermore suggesting interventions to reduce excessive smoking and prevent nicotine dependency effectively, the questionnaires of perceived stress(stressful experiences), ways of stress coping(passive and active copings), smoking motives, social influence, age, amounts of smoking, and nicotine dependency were administered to smokers among medical students in Chosun university(n=186). 1) As a result of classifying smokers by the types of smoking, the most was a type of smokers to reduce negative emotions and the next in order were addictive smokers, smoker for stimulation, smoker for pleasure, etc. 2) The effects of motive, age, and active coping style were significant, but the effects of perceived stress, passive coping style, and social influence were not significant in average amount of daily smoking. 3) The effects of motive, social influence, and age were significant, but the effects of perceived stress, passive and active coping styles were not significant in the degree of nicotine dependency. To summarize, it is concluded that there were a lot of people who smoke to solve negative emotions, but the direct effects of perceived stress and passive coping style on both average amounts of daily smoking and the degree of nicotine dependency were not significant. On the other hand, motive, age, active coping style, and social influence were proved to be more important variables than the others in explaining college students' smoking.