• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.67-67
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• 2017

We developed the breeding materials with diverse grain size and shape in japonica rice. Grain size and shape are important factors affecting consumer preference and choice. However, most of Korean japonica rice cultivars have small, short, and round grain. To diversify the grain size and shape of japonica rice, we conducted the breeding program using donor parents, Jizi1560 and Jizi1581. Jizi1560 and Jizi1581 are japonica germplasm with extremely large grain. Four crosses between the each donor parents and high yielding japonica rice cultivars, Deuraechan and Boramchan, were constructed and then anther culture method was applied. We obtained 290 doubled-haploid (DH) lines with appropriated morphological traits and selected 91 DH lines with diverse grain size and shape. The grain related-traits of the selected DH lines showed a higher diversity when compared with 319 cultivars developed by NICS (264 japonica, 13 black, and 32 Tongil type cultivars). We designated the selected DH lines, four parents, and Daeripbyeo 1, large grain japonica cultivar, as the breeding materials for further analysis. The breeding materials were classified into five groups, A to E, based on the grain-related traits. Group A (including Jizi1581) and Group B (including Daeripbyeo 1) showed similar grain width, whereas Group A exhibited longer grain length and heavier grain weight. Group C (including Deuraechan and Boramchan) showed shorter and rounder grain shape and smaller grain size than any other groups. Group D including solely Jizi1560 had extremely large grain, such as the longest grain length, width, and thickness and heaviest grain weight. Group E including only two DH lines had long and slender grain shape, so that showed the highest ratio of length to width. The grain size and shape of the breeding materials exhibited beyond the characteristics of previously developed Korean japonica cultivars. The breeding materials will be applied in the breeding programs to diversify the grain size and shape of japonica rice.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10b
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• pp.47-50
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• 2003

Grain size of the $\alpha$ phase is computed during isothermal forging of the TC6 aerofoil blade, by combining FE with the Yada's model of grain size. The present results illustrate the grain size and distribution of the $\alpha$ phase during isothermal forging of the TC6 aerofoil blade' in detail. The computed results show that height reduction, deformation temperature, hammer velocity and friction have significant effect on distribution of the equivalent strain, and that height reduction, deformation temperature and hammer velocity have more significant effect on grain size of the $\alpha$ phase than friction between billet and die.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.3
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• pp.479-487
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• 1987

In order to predict the effects of droplets distributions such as number density and droplets size on group combustion characteristics and flame structure for liquid fuel sprays, modifications of group combustions model were made by changing the droplets distributions from uniform to non-uniform. Various droplets distribution models were adopted in this analysis to examine the effect of number density distribution on combustion characteristics and the difference between uniform and non-uniform droplets size distributions for a spherical droplets cloud. As results of present study, hollow droplets could with outer concentrating distribution has shorter total combustion time compare with the case of solid droplets cloud with inner concentrating distribution. Uniform droplets size distribution model predicts the shorter total combustion time compare with non-uniform droplets size distribution model, and the uniform droplets size distribution model may be used to predict the total combustion time for the droplets cloud containing larger initial size of droplets.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.80-89
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• 2021

In Korea, marine fish landed at ports are randomly sampled on a periodic basis (e.g., daily or weekly), and body sizes (e.g., lengths and weights) of those sampled fish are measured. The motivation for our study is whether or not such measurements reflect the size distribution, especially the length distribution of fish landed (= a population), because such length measurements are key data for a length-based assessment model. The current sampling method is to sample fish landed at ports by body size group (e.g., very small, small, medium, large, very large), using the sampling weights as the number of boxes by body size group. In this study, we showed that length composition data about fish sampled by the current method did not represent the length frequency distribution of the fish landed, and suggested that an alternative sampling method should be applied of using the sampling weights as the number of fish landed by body size group. We also introduced a method for determining an appropriate sample size.

• Journal of the Korean Ceramic Society
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• v.46 no.2
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• pp.175-180
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• 2009

Multilayer ceramic capacitors (MLCCs) have continually been made smaller in size and larger in capacity in resent years. However, the end termination electrode is still thick in many MLCCs. In this study, we used small grain glass frit to embody thin film and highly densification in the end termination by improve sintering driving force with well-dispersion and rising surface energy. Pastes were fabricated using size changed glass frit, such as 0.1 ${\mu}m$, 0.5 ${\mu}m$, 1.0 ${\mu}m$, 4.0 ${\mu}m$. Fabricated pastes were applied 05A475KQ5 chip and fired various sintering temperatures to analyze sintering behavior of pastes. Consequently, small glass frit used pastes have many merits than larger, such as well-dispersion, improve cornercoverage and surface roughness, possibility of low temperature sintering. However, we confirmed that small glass frit used pastes have narrow sintering window by rapid completion of sintering densification.

• Journal of Preventive Medicine and Public Health
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• v.22 no.3 s.27
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• pp.323-327
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• 1989

Carbon monoxide diffusing capacity(DLco) was evaluated before and after nifedipine administration in coal workers' pneumoconiosis by the size of radioopacity. Nifedipine was administered to 18 men and 17 men of small round opacity group and large opacity group respectively. Placebo was administered to 19 men and 15 men of small and large opacity group respectively. In large opacity group DLco was increased after nifedipine administration. But, it was not significant statistically(0.05

• Journal of the Korean Magnetic Resonance Society
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• v.13 no.2
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• pp.84-95
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• 2009

The purpose of this study was to evaluate the usefulness of the measurement of corpus callosum (CC) size in the Alzheimer patient by using magnetic resonance (MR) midsagittal image. We performed MR scanning in 20 normal high age group, and in 20 mild cognitive impairment (MCI) group, and in 20 Alzheimer disease (AD) group. The following parameters were employed in AD group: TRITE/FA 6650ms/66ms/$90^{\circ}$, NEX 2, Thickness/Gap 2/0, FOV 220mm. The magnetic field strength was used at 3.0 Tesla. We selected midsagittal image of the brain by using view forum program, measured CC size, which were anteroposterior length, diameter of genu, body, narrowing portion, and splenium. The present study demonstrates that CC size of Alzheimer disease can be useful for clinical assessment concerning the diameter of genu, body, and splenium.

• Journal of Korean Institute of Industrial Engineers
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• v.9 no.1
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• pp.23-31
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• 1983

A group scheduling problem, which is production scheduling problem associated with the concept of group technology, is studied under due date constraints in multi-stage manufacturing systems. The purpose of this paper is to develop and evaluate a practical heuristic procedure for determining group sequence and job sequence within each group to minimize total tardiness in multi-stage manufacturing systems. A heuristic algorithm has been developed by introducing the concept of relative measures of job tardiness and group tardiness for job sequencing and group sequencing, respectively. A numerical example is shown to illustrate the proposed procedure. The heuristic algoirthm is tested by comparisons with problems with known optimal solutions and also with random group schedules for a set of large-size problems. Results indicate that the proposed heuristic algorithm provides good solutions with small computational requirements, and thus is viable for large size problems in practice.

• Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.191-195
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• 2007

The aim of this study was to assess whether size-rank at the juvenile stage is associated with growth performance and sex ratio in olive flounder (Paralichthys olivaceus). Juveniles (mean body weight, $8.8{\pm}0.9\;g$) were selected from two age groups, with the high size-rank group (HSRG) fish in the upper 19.3-67.3% of 104 days post-hatching (dph) age group and the low size-rank group (LSRG) fish in the lower 9.0-55.7% of 116 dph age group. Triplicate groups of 100 fish were reared over 32 weeks. A heavier final body weight was observed in the HSRG ($360{\pm}12\;g$) compared to the LSRG ($315{\pm}9\;g$, P<0.05), whereas no differences in feed intake, feeding efficiency, and mortality were seen between the experimental groups. The percentage of females was significantly higher in the HSRG (51.7%) than in the LSRG (30.8%, P<0.05). In addition, a remarkable increase in growth was recorded in females, indicating that the relative frequency of females increased with a body weight increase. The results suggest that high size-rank juvenile olive flounder have better growth performance and a higher percentage of females, because females start growing faster than males before size grading occurs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.6
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• pp.260-265
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• 2014

Objectives: The aim of this study was to verify the clinical effectiveness of decompression in decreasing the size of a cyst. In addition to the different types of cysts, we tried to reveal what effect host factors, such as the initial size of the lesion and the age of the patient, have on the velocity of cyst shrinkage. Materials and Methods: With the aid of a panoramic view, we measured the size of the cysts before and after decompression in 13 dentigerous cysts (DCs), 14 keratocystic odontogenic tumors (KTOCs), and 5 unicystic ameloblastoma (UA) cases. The velocity of shrinkage in the three cystic groups was calculated. Relationships between the age of the patient, the initial size of the cyst, and the shrinkage velocity were investigated. Results: The three types of cysts showed no inter-type differences in their velocity of shrinkage. However, there was a statistically meaningful relationship between the initial size of the lesion and the absolute velocity of shrinkage in the DC group (P=0.02, R=0.65) and the KTOC group (P=0.02, R=0.56). There was also a significant relationship between the age of the patient and the absolute velocity of shrinkage in the KTOC group (P=0.04, R=0.45) and the UA group (P=0.04, R=0.46). Conclusion: There was no difference in the decrease in size due to decompression among the different types of cysts. However, the age of the patient and the initial size of the lesion showed a significant relationship with the velocity of shrinkage.