• Journal of Biosystems Engineering
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• v.35 no.3
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• pp.158-162
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• 2010

The effect of fuel injection characteristics on engine performance has been known for improving fuel economy and emission reduction. In this study, the spray characteristics of crude palm oil blended fuel with conventional diesel fuel was investigated. The experiments were performed to evaluate the effect of crude palm oil blending ratio and injection pressure on the spray behavior. The droplet size of injected fuel was analyzed through laser diffraction particle analyzer (LDPA). Also, spray atomization characteristics were investigated in terms of Sauter mean diameter (SMD) and droplet distribution at various injection conditions. Fuel containing crude palm oil has different spray pattern on account of the high viscosity. Through those experimental results, we found that the increase of blending ratio made droplet size larger, SMD of biodiesel 100% was increased 30.2% than that of diesel fuel 100% under injection pressure of 60 MPa.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1671-1677
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• 2006

A total of two hundred twenty eight half-sib chickens were scored for allele size at 20 microsatellite loci to estimate individual heterozygosity and mean $d^2$. The averages of microsatellite heterozygosity, allele per locus and mean $d^2$ were 0.39, 3.6 and 49, respectively. The body weight was measured biweekly from birth to twelve weeks of age. Gompertz function was assumed to simulate body weight and to estimate the growth model parameters. Due to sex effect on body weight, the regression of body weight on heterozygosity as well as on mean $d^2$ in males and females was analyzed separately in the present study. Positive correlations were found between microsatellite heterozygosity and body weight in males and females (p<0.05). Positive correlation also observed between individual heterozygosity and simulated maximum daily gain estimated from Gompertz function in female chickens (p<0.05). There were no significant correlations between mean $d^2$ and body weight. The results suggest that local effect hypothesis could explain the correlations between heterozygosity and fitness-related traits in the domesticated chicken population, rather than the general effect hypothesis does.

• Korean Journal of Animal Reproduction
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• v.27 no.4
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• pp.287-297
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• 2003

The aim of this review is to give insight into the reproduction potential of the Korean native goat(KNG) doe. The mean age of the first estrus in the KNG doe is 141.24$\pm$18.l7 days. The length of the estrous cycle was recorded as being 20.58$\pm$2.63 days, with the mean duration of estrous period being 17.8$\pm$7.3 to 32.9$\pm$1.2 h, and the duration of the post-partum anestrous period being 13.4(9 to 18) to 30.1$\pm$3.8 days in the KNG doe. The ages at first delivery are 10 to 12 months(56.3％) in the KNG doe. The KNG does are no restricted breeding season, because estrus and kiddings are observed throughout the year. The mean gestation period of the KNG doe is recorded as being 150.69$\pm$6.14 days with parities having no significant effect on gestation length. The mean interval between parturitions in the KNG doe is 207.78$\pm$1.72 days with parities and birth type having no significant effect on kidding intervals. The mean litter sizes at birth in the KNG doe are 1.69$\pm$0.03 heads, and litter size at birth was affected (P<0.05) by parity. The mean birth weight of kid in the KNG is 2.04$\pm$0.30 kg with a variety as being 2.28$\pm$0.26, 2.11$\pm$ 0.30 and 1.64$\pm$0.19 kg for singles, twins and triplets over of birth type, respectively. The mean mortality of 635 kids in the KNG is 23$\pm$1 ％ with a variety as being 28$\pm$3, 21$\pm$2, 16$\pm$3 and 46$\pm$15 ％ for singles, twins, triplets and quadruplets of birth type, respectively.

• Journal of ILASS-Korea
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• v.3 no.3
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• pp.42-48
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• 1998

This study describes the spray structure of gasoline port injectors by using phase Doppler particle analyzer(PDPA) and particle motion analysis system(PMAS). The characteristics of fuel spray such as the spray penetration, spray angle and breakup processes were obtained by PMAS and the droplet size and mean velocity were measured by PDPA system. Pintle type and two-hole type injectors were used as gasoline port fuel injectors under various injection pressures. The effect of injection pressure on the droplet mean diameter and axial mean velocity of droplet were investigated under the various injection conditions. In addition the comparison of breakup processes for the two types of injectors was also conducted. It Is shown that pintle type injector has smaller droplet size than that of two-hole type injector.

• The Journal of Industrial Distribution & Business
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• v.12 no.11
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• pp.17-31
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• 2021

Purpose: Despite the fact that face (i.e. Chemyon) is deeply-rooted in Korean culture and significantly affects the behavior of Korean people, the effect of face on leisure consumers' consumption behavior has only reported mixed findings, that is, significant and/or insignificant face effects have been reported. It is necessary to integrate prior research findings, and comprehensively examine the effect of face on leisure consumers' consumption behavior. The purpose of this study was to investigate the effect (i.e. effect size, and moderating variables) of face on leisure consumers' consumption behavior through meta-analysis. Research design, data and methodology: Among 1,019 face-related academic studies, retrieved from the academic research information services (RISS), 34 studies and 300 cases examining the effect of face on leisure consumers' consumption behavior were finally included for meta-analysis. Face measured as face sensitivity and/or a face sensitivity sub-component (shame-consciousness, formality-consciousness, and other-consciousness) were integrated in the meta-analysis. Leisure consumers' consumption behavior was classified as antecedents of purchase (overall conspicuous consumption tendency, overall symbolic consumption tendency, personality, high price, high quality, brand seeking, fashion seeking, enjoyment, other person (interpersonal) consideration, position, reference group, and attitude), purchase (purchase intention, unplanned purchase, purchase, and expenditure), and post-purchase (satisfaction, repurchase, and post-purchase). The data used in the meta-analysis was comprised of correlation coefficients, and the meta-analysis was performed using the R-program. Results: The overall mean effect size of face on leisure consumers' consumption behavior was .248. It was found that the effect size was the largest in the order of shame-consciousness face, formality-consciousness face, and other-consciousness face. Among the types of leisure consumers' consumption behavior categorized as dependent variables, the effect size was found to be largest in the order of position, attitude, reference group, post-purchase behavior, brand seeking, personality, trend seeking, etc. In addition, it was found that the leisure types moderated the effect size of face on leisure consumers' consumption behavior. The effect size was found to be largest in the order of skin diving, baseball, various leisure participation, dance, gambling, golf, etc. Conclusions: Face moderately or significantly influence leisure consumers' consumption behavior.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.274-279
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• 2011

In order to know the effect of seed size on the early plant life history, we measured the rate of germination, early growth and winter survival of four oak species with different acorn size (large, medium and small). The mean germination rate was higher in the larger seed species ($Q.$ $acutissima$ and ($Q.$ $variabilis$) than those of the smaller seed species ($Q.$ $aliena$ and $Q.$ $serrata$). Within $Q.$ $variabilis$, the germination rate decreased with larger acorn size class but that of rest other species was not significantly affected by the acorn size. The early mean growth rate decreased with acorn size in the order of $Q.$ $acutissima$, $Q.$ $variabilis$, $Q.$ $aliena$ and $Q.$ $serrata$. The early mean growth rate was higher in large or medium size than in small size of $Q.$ $acutissima$ and $Q.$ $variabilis$, but it showed no difference with acorn size in $Q.$ $aliena$ and $Q.$ $serrata$. Survival rate in winter was the highest in the medium acorn size among 4 oak species, the seedling of $Q.$ $serrata$ and $Q.$ $variabilis$ did not survive in both large and small acorn size. These results indicate that seed size influences a different effect on the early plant life history stage.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.256-264
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• 1989

Modified Blalock-Taussig operation remains the standard technique of systemic-to-pulmonary artery shunt in patients of congenital heart disease with decreased pulmonary blood flow. We reviewed the 41 patients who had been performed modified Blalock-Taussig operation from March 1985 to Feb. 1988, and angiographically measured pulmonary artery size before and after shunt, and calculated pulmonary artery index [PAI] and ratio of left and right pulmonary artery to descending aorta[[LPA+RPA]/dAo]. The mean duration of palliation after shunt operation was 624 days and mean age of the patient at shunt operation was 3.59 years. Mean PAI increased significantly from 131.15*67.11 mm2/M2 preoperatively to 232.70*84.46 mm2/M2 postoperatively. Mean ratio of right and left pulmonary artery to descending aorta also increased significantly from 1.48*0.40 preoperatively to 1.92*0.50 postoperatively. All patients manifested clinical improvement; there was mean decrease in hematocrit of 8.95%, mean increase in arterial oxygen saturation of 11.08%. Pulmonary arterial growth was not influenced by age at operation, initial pulmonary artery size, or graft size, but significantly influenced by antegrade flow. The patients who have some antegrade flow were in more increase of PAI. There were no linear correlation between change of PAI, change of [[LPA+RPA]/dAo], SaO2, and duration. But, according to Scatterplot between change of PAI and duration, some complex correlation was suggested and mean PAI was decreased after 2-year palliation. We concluded that modified Blalock-Taussig operation is excellent palliative surgery for pulmonary artery growth especially on the patient who have some antegrade flow, and the proper duration of palliation was about 2 years.

• Korean Journal of Exercise Nutrition
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• v.23 no.1
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• pp.36-47
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• 2019

[Purpose] We conducted a meta-analysis to evaluate the effects of Taekwondo training on the physical fitness factors in Korean elementary students comprehensively and quantitatively. [Methods] We classified research studies published until November 2018 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and selected a total of 17 research items; a meta-analysis of these items was then conducted. We used the Comprehensive Meta-Analysis 3.0 and Review Manager 5.3 to analyze the mean effect size, study quality, and publication bias. [Results] Taekwondo training improved the cardiopulmonary endurance, muscle endurance, and power of the elementary students, but was not practical or less useful on other physical fitness factors. The meta-regression analysis of the cardiopulmonary endurance and power items showed that the effect size was large when the sample size was small. Therefore, it is necessary to consider the sample size in interpreting the effect size for these two items. Further, during correction of the publication bias for the power items, the improvement effect by Taekwondo training was eliminated. [Conclusion] Taekwondo training is helpful for improving the cardiopulmonary endurance and muscle endurance of Korean elementary students but is not useful for other physical fitness factors.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.5
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• pp.11-22
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• 1994

The pupose of this study is to measure droplet size and velocity simultaneously for a transient diesel fuel spray in a quiescent chamber at atmospheric temperature and pressure. Generally, diesel combustion phenomena is mainly governed by characteristics of injection system and fuel spray. Therefore we need to clarify these characteristics for developing more economical diesel systems. In this study, correlation between droplet size and velocity was measured at downstream distance from nozzle. Governing parameters are pump speed and fuel quantity for the detailed nature in this transient diesel fuel spray. It is observed effect to the droplet size and velocity distribution. Velocity(peak, mean, rms), number density and droplet size were investigated simulaneously using PDA in the spray. Various results are presented to illustrate the effects of operation factors and correlation between the droplet diameter and velocity.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.9_10
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• pp.1172-1177
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• 2003

Microcapsules were prepared by complex coacervation between gelatin and gum arabic. The object of this work is evaluation of the effect of jelly strength, hardening agent on the particle size distribution, surface morphology and DSC. It was found that the 300bloom jelly strength caused microcapsules' size larger. When the amount of hardening agent increased, the particle mean diameter was larger. The amount of hardening agent was determined to be 10m1 for getting suitable size to finish the fabric.