• Journal of the East Asian Society of Dietary Life
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• 제26권2호
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• pp.181-191
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• 2016

This study aimed to investigate current nutrition education and effective plans for nutrition teachers in schools. Data were collected by a face-to-face questionnaire. Surveyed schools were elementary, middle, and high schools at percentages of 32.4%, 35.1%, and 32.4%, respectively. Percentage of nutrition education was above 90%, whereas off-line education was very uncommon in middle (8.3%) and high schools (27.3%) compared with elementary schools (63.6%), (p<0.05). Satisfaction of nutrition education was also very low in middle (7.7%) and high schools (8.3%) when compared with elementary schools (41.7%), (p<0.05). The main reason for this was due to 'work overload of mealing service (44.4%)' and 'insufficient time of students (25.9%)'. Effective education plans were as follows: beginning of education and education scale were 'elementary school (67.6%)' and 'below 20 people (81.1%)', and the most preferred counterplan was 'development of diverse education programs (4.81 score)' > 'systematic education process (4.76 score)' > 'professional nutrition education (4.51 score)'. Most important duty was 'nutrition education and consultation (51.4%)', although it achieved the lowest satisfaction at a score of 2.46. Overall analysis, demand and awareness of nutrition teachers for nutrition education were very high. Therefore, an institutional strategy and environmental improvements are required by setting up curriculum subjects and developing diverse education programs for systematic nutrition education.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제25권4호
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• pp.245-252
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• 2016

Girth gears are applied in the mining, cement, and mineral processing industries and used in various types of horizontal mills, rotary dryers and kilns, and other heavy-gear ring applications. The large ring gears are normally fitted outside mills or kilns to provide the primary rotational drive. Recently, an external pinwheel gear set (e-PGS) was introduced to overcome manufacturing problems associated with girth gears. e-PGS is also suitable for low-speed, heavy-duty mechanical transmission and dusty and poor-lubrication conditions. This paper first presents a new profile modification of root relief for the e-PGS cam pinion. We then investigate load-stress factors to estimate the surface fatigue life by varying the shape design parameters. The results show that the contact fatigue life of an e-PGS can be extended significantly by increasing the profile shift coefficient. However, support bearing life of the pinwheel depends more on the contact force distribution than the profile shift coefficient.

• Journal of Bio-Environment Control
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• 제26권2호
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• pp.123-132
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• 2017

This study was aimed to investigate the effect of 1)irradiation with several different ratios using red, green, and blue LEDs and 2)various pulsed light irradiation with 50% duty ratio using red and blue LEDs on the growth and morphogenesis of three lettuce cultivars (Lactuca sativar L. cv. 'Jukchukmeon', 'Lolo Rosa', and 'Grand Rapid') in hydroponics culture system for 4 weeks after transplanting. Seeds were sown in rock-wool plug trays and they were placed in a culture room which was controlled at $23{\pm}1^{\circ}C/18{\pm}1^{\circ}C$ temperature and 50-60/70-85% for day and night, respectively, during cultivation period. Irradiated RGB ratios with LEDs were 6:3:1, 5:2.5:2.5, 3:3:4, 2:2:6, and 1:1:8 with $110{\pm}3{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD on the surface of cultivation bed. The frequencies of pulsed lighting was 50, 100, 500, 1,000, 5,000, 10,000, 25,000Hz (20, 10, 0.1, 0.04 ms) with red and blue LEDs and 50% duty ratio. At the RGB ratio of 6:3:1, the average fresh weight of 'Jukchukmeon' was significantly higher than that of other RGB treatments, but no significant difference compared to the fluorescent treatment. The average fresh weight at 1:1:8 RGB ratio in 'Lolo Rosa' was significantly lower than that of other RGB treatments. Leaf number and fresh weight of 'Grand Rapid' were significantly lower in the control and 1:1:8 RGB treatments, compared to the other RGB treatments. As the ratio of blue light increased, leaf length decreased and leaf shape became round in three lettuces. Although there is little change in growth, it could not be found any tendency to affect the growth and morphogenesis of three lettuces caused by increasing or decreasing frequency of pulsed lighting with 50% duty ratio at the $72{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제37권4호
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• pp.399-405
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• 2009

The focal plane image stabilization for a satellite camera is one of the an effective method which can increase the satellite camera's image quality by removing the motion disturbance of a focal plane. The objectives of this article are to introduce the concept of the focal plane image stabilization and determine the best driving conditions of the actuator for the response and thrust. Under various driving condition the experiments have been performed to investigate the response and thrust characteristics of the piezoelectric driven stick-slip actuator of the focal plane image stabilizing device. From experiments, the best driving frequency and duty ratio for the magnesium slider are 70 kHz and 27%, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• 제17권7호
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• pp.642-648
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• 2005

This study has been conducted to investigate the thermopneumatic and flow characteristics of diffuser/nozzle based thermopneumatic micropumps. In this study, a transient three-dimensional numerical analysis using FSI (Fluid-Structure Interaction) model has been employed to analyze the effects of the interaction between the membrane and two fluids (air and water) in the thermopneumtic micropump. The transient temperature and pressure in the cavity, the transient displacements of the membrane and the net flow rate of the micropump have been closely calculated for the frequency of 1 Hz. It has been found that the difference of the flow rates at the inlet and outlet is larger in the cooling period than in the heating period and that the duty ratio is very important in association with pump performance because the temperature in the cavity ascends drastically in the heating period and descends slowly in the cooling period. This study can be regarded as fundamental understandings for the design and analysis of thermopneumatic micropumps.

• Journal of Korean Academy of Nursing
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• 제48권3호
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• pp.311-322
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• 2018

Purpose: The purpose of this qualitative research was to investigate chronically ill patients' perception of hospital nurses. Methods: Individual in-depth interviews and qualitative content analysis were used for data collection and analysis respectively. Participants were 13 chronically ill hospitalized patients or outpatients in three universities hospitals. All interviews were recorded and transcribed verbatim. Data were analyzed using the qualitative content analysis suggested by Graneheim and Lundman (2004). Results: Three themes emerged from the 10 sub-themes, which were categorized from the 21 condensed meaning units by interpreting the underlying meanings. The three themes were "person giving comfort and support by caring", "person facilitating the process of healing", and "person taking the initiative in power relations". Two themes involved positive experiences of patients and the other included negative ones. Conclusion: The results showed that the participants perceived the hospital nurses as devoted to caring for patients and facilitating treatments, but authoritative in performing their duty. Based on these results, it is recommended that hospital nurses improve their nursing knowledge, skills and humanistic attitude.

• Korea Journal of Hospital Management
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• 제23권2호
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• pp.67-81
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• 2018

Purposes: The purpose of this study was to investigate the relationship between male nurse's gender stereotype, role conflict and organizational commitment. Methodology: Data were collected from 169 male hospital nurses from August, 2016 until September. The Male nurse's gender stereotype, role conflict and organizational commitment were measured using a structured questionnaire. Collected data were analyzed using SPSS/win 23.0 for windows. Descriptive statistics, t-test, ANOVA and Pearson's correlation were used. Findings: There were statistically significant differences in the gender stereotype by general characteristics such as age and military duty. There were statistically significant differences in the role conflict by general characteristics such as education level and position. There were statistically significant differences in the organizational commitment by general characteristics such as the hospital's location and hospital type. Gender stereotype and role conflict had no significant correlation (r=-0.050, p=.516). A statistically significant positive correlation was detected between male nurse's gender stereotype and 'continuance commitment' (r=0.272, p<.001). A statistically significant positive correlation was detected between male nurse's role conflict and 'continuance commitment' (r=0.178, p=.021). Practical implications: The result of this study indicate that to reduce role conflict of workplace environment and induce the affective commitment of male nurses within a female-centered nursing organization should be sought.

• Transactions of the Korean Society of Automotive Engineers
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• 제14권2호
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• pp.145-150
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• 2006

Recently emission regulation on diesel vehicles is getting stringent and research on aftertreatment technology such as DPF and DOC has been carried out actively. Even though PM(Particulate matters) reduction efficiency in DOC is relatively low but the structure is simpler and very effective in the reduction of gas materials and unregulated materials. Therefore it has been applied to smaller diesel vehicles. The aims of this research is to investigate the emission reduction characteristics of DOC; DOC performance of regulated and unregulated material emission reduction. It results a Pt based catalyst demonstrated higher emission reduction efficiency than a Pt-V based catalyst in CVS-75 mode, and also the reduction efficiency of unidentified material was excellent.

• Transactions of the Korean Society of Automotive Engineers
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• 제9권2호
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• pp.59-66
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• 2001

This experimental study is to investigate the flow characteristics of the multi-hole nozzle used in the fuel injection system of a heavy-duty diesel engine. A multi-hole diesel nozzle with a 2-spring nozzle holder was used in this study and without changing the total orifice exit area, its hole number varied from 3($d_n$=0.42mm) to 8($d_n$=0.25mm). The injection pressure and needle lift were measured and Bosch type injection rates measurement system was used. The discharge flowrates of each orifice in the multi-hole nozzle changed by the flow conditions inside the nozzle sac hole. In case that pump speed and injection quantity were low, the orifice located in the vertex of nozzle tip had a great deal of injection quantity compared with that of others. As the increment of multi-hole number, the injection duration and the mean injection pressure decrease. The mean and peak injection rates, however, increase. Actually, the mean flow coefficient(${C_d}_{(mean)}$) increases, too. The flow coefficient of the multi 8 hole was evaluated as Cd(mean)=0.74 and that is the maximum value among the examined conditions.

• Convergence Security Journal
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• 제16권3_2호
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• pp.43-54
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• 2016

Korea's police force has successfully performed its difficult mission of maintaining public order while overcoming difficulties at home and abroad during the past half century. However, the environment in which the forces of law a nd order operate has exponentially increased the demand for, and difficulties faced by, the agents of law enforcement in recent years because of the country's rapid globalization, as well as the move to democracy and localization, and the extensive developments in industrialization and information technology diffusion. This study also intends to investigate the appropriate limits of law enforcement and the use of force by policemen, and the general public's perception of the police as they fulfill their duty of protecting citizens' rights.