• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.342-347
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• 2008

Mortality and growth rate of the soft coral, Dendronephthya gigantea, from Jejudo Island on the southern coast of Korea were investigated from February 2003 to October 2004 using SCUBA diving. 48 individuals with variable sizes of D. gigantea of the depth of 15m were tagged with flagging tapes and plastic films, and then monitored with two month intervals. The average mortality of two-month term for the study period was 50.4%, with the peak of 84.6% during the summer storms in August - October 2003. About the size class mortality, individuals of size class I(${\leq}$10 cm) showed the highest mortality, followed by size class III(>20 cm) and size class II(10 cm-20 cm). Growth rate did not show a seasonal pattern. For growth in length, individuals of D. gigantea grew about 3cm in average for two-month period, with a maximum growth of 6.4 cm which occurred in August - October 2003. For growth in diameter, individuals grew about 0.3 cm for 2 month term, with a maximum of 1.4cm in April - June 2004. Individuals of size class I usually grew faster than those of larger size classes. D. gigantea population in Jejudo Island was strongly affected by summer storms, which was due to annual event of summer typhoon. Never the less, it appears that the local population can be maintained by fast growth of the juvenile stage and active recruitment to compensate the high mortality caused by the summer disturbance.

• Fisheries and Aquatic Sciences
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• v.21 no.11
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• pp.34.1-34.13
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• 2018

Sexual maturity ($L_{50}$), the length at which 50% of fish in a size class are mature, is a key aspect of domestication of new fish species because it guides the procedure for identification of appropriate broodstock size for artificial spawning. In this study, the $L_{50}$ was determined for 1083 Barbus altianalis samples obtained from Lake Edward and the Upper Victoria Nile. Gonads of freshly killed samples were examined macroscopically and verified with standard histological procedures for the maturation stages that were used to determine $L_{50}$. Oocytes and spermatogenic cell sizes were compared for fish obtained from both water bodies. Results indicated that there were no variations in macro gonad features observed for fish from Lake Edward and Upper Victoria Nile. Similarly, there were no significant differences in oocyte sizes (P > 0.05) between the two populations but significant differences in spermatogenic cell sizes were noted (P < 0.05) except for spermatozoa (P > 0.05). This however did not suggest peculiar differences between the two populations for staging the gonads. Consequently, no staging variations were suggested for both populations in determination of $L_{50}$. Sexual maturity was found in the same class size of fork length (FL) 20-24.9 cm and 35-39.9 cm for males and females from both water bodies, respectively. At this FL, however, males were too small, and for good selection of vigor broodstocks for spawning and conservation purposes, they are better picked from class size of 30-34.9 cm FL and above. These findings were crucial for integration of appropriate breeding size in spawning protocol by farmers and fisheries scientists conserving wild B. altianalis populations.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.4
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• pp.274-280
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• 2007

This paper demonstrates an efficiency improvement of the class E power amplifier (PA) by tuning-out the input capacitance ($C_{IN}$) of the power HBT with a shunt inductance. In order to obtain high output power, the PA needs the large emitter size of a transistor. The larger the emitter size, the higher the parasitic capacitance. The parasitic $C_{IN}$ affects the distortion of the voltage signal at the base node and changes the duty cycle to decrease the PA's efficiency. Adopting the L-C resonance, we obtain a remarkable efficiency improvement of as much as 7%. This PA exhibits output power of 29 dBm and collector efficiency of 71% at 1.9 GHz.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.60-85
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• 2014

The study is for tracing the mutational process, considering the transformational process of wooden chamber tombs in Gyoungju region during 2~6 century. In addition, class features and the meaning of tombs were studied. First of all, the wooden chamber tombs were classified into 10 different styles(1A~IVC), based on the filling materials, the ways of structure, and the structure of burial chamber. There were only one or two tombs that belongs to the highest classes 'Ga'~'Da' in each period, which has the numeral features. Furthermore, the styles of the central wooden chamber tombs according to the period and the region have distinctive features and have changed so far. It shows that there are the rank among the tombs in the regions. In other words, regarding the ranks of the class 'Ga'~'Cha', there were strict rules and the limitations on the size of the tombs and the number and the quality of the burial relics. It means that the inner-outer size or the structure of the tombs and the number, quality of the burial goods depended on the buried person's birth or social classes, or achievements. Based on Shila social classes, the class 'Ga' tombs were for the highest classes when considered the size, burial relics, and the quality. The class 'Na' and 'Da' tombs were for the higher classes, 'Ma' for middle classes, 'Ba', 'Sa' for lower classes. In addition, 'Ah', 'Ja' tombs were for higher commoner, 'Cha' for lower commoner. Thus, class 'Ga'~'Sa' is the leading class of Shila.

• Journal of Fashion Business
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• v.8 no.1
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• pp.133-140
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• 2004

In order to compare the pattern sizes of toddlers' brands, the apparel size #95 and #100, #110 were surveyed, while upper body lengths, bust circumferences and waists, hip circumferences, shoulder length, sleeve length, neck circumferences of toddlers' underwears were examined. As a result, it was found that upper body lengths, chest circumferences and lower body lengths of toddlers' underwears differed more or by $2.0cm{\sim}3.0cm$ among brands than other sizes. In case of underwear size #95, the average upper body length was 32.8cm; the upper body size of "c" brand was longest or 33.5cm, while that of "e" brand was shortest or 32.0cm. In case of size #80, the average upper body length was 36.0cm; the upper body size of "a" brand was longest or 37.0cm, while that of "e" brand was shortest of 35.0cm. Such findings may be attributable to the fact that the main customers of "a" and "b" brands whose pattern sizes are larger are middle or lower class people who tend to buy larger toddlers' apparels than their children's actual body sizes. In contrast, "e" brand seems to target the upper class who prefers the apparels almost fitting their children's actual body sizes.

• Journal of Fashion Business
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• v.7 no.5
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• pp.101-107
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• 2003

In order to compare the sizes of infants;brands, the apparel size #70 and #80, #90 were surveyed, while upper body lengths, bust circumferences and waists, hip circumferences, shoulder length, sleeve length, neck circumferences of infants' underwears were examined. As a result, it was found that upper body lengths, chest circumferences and lower body lengths of infants' underwears differed more or by $2.0{\sim}3.0cm$ among brands than other sizes. In case of underwear size #70, the average upper body length was 32.8cm; the upper body size of "c" brand was longest or 33.5cm, while that of "e" brand was shortest or 32.0cm. In case of size #80, the average upper body length was 36.0cm; the upper body size of "a" brand was longest or 37.0cm, while that of "e" brand was shortest of 35.0cm. Such findings may be attributable to the fact that the main customers of "a" and "b" brands whose pattern sizes are larger are middle or lower class people who tend to buy larger infants' apparels than their children's actual body sizes. In contrast, "e" brand seems to target the upper class who prefers the apparels almost fitting their children's actual body sizes.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.720-725
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• 2010

On the basis of vegetation data in the 9.12 ha (380 m ${\times}$ 240 m) permanent sample plot of the spruce-fir valley forest in Liangshui National Reserve of Xiaoxing'an Mountains, the study was conducted to evaluate spatial distribution pattern and spatial association by using point pattern analysis for living and dead trees of Larix gmelini by DBH size class. The number of L. gmelini were counted as 59 living stems/ha (6.42 $m^2$/ha of basal area) and 34 dead stems/ha (2.86 $m^2$/ha of basal area). The distributional curve of diameter class exhibited bimodal shape. The analysis of spatial distribution patterns of all living larch stems noted the clumped distribution on the whole. The size of larch aggregates of dead stems was decreased as diameter class was increased. The distribution of dead stems became gradually randomized with decreased clumped size as the scale increased. Living stems and dead stems of the larch had positive spatial association at most of scales, illustrating that the occurrence of mortality of the larch tree was closely related to the distribution pattern of living larch trees.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2541-2546
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• 2009

In the anti-collision scheme proposed by EPCglobal Class-1 Gen-2 standard, the frame size for a query round is determined by Q-algorithm. In the Q-algorithm, the reader calculates a frame size without estimating the number of tags in it's identification range. It uses only the slot status. Therefore, the Q-algorithm has advantage that the reader's algorithm is simpler than other DFSA algorithms. However, the standard does not define an optimized parameter value for adjusting the frame size. In this paper, we propose the optimized parameter values for minimizing the identification time by various computer simulations.

• Computers and Concrete
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• v.28 no.5
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• pp.521-532
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• 2021

Present paper focuses on the modeling of size effect on the compressive strength of normal concrete with the application of Discrete Element Method (DEM). Test specimens with different size and shape were cast and uniaxial compressive strength test was performed on each sample. Five different concrete mixes were used, all belonging to a different normal strength concrete class (C20/25, C30/37, C35/45, C45/55, and C50/60). The numerical simulations were carried out by using the PFC 5 software, which applies rigid spheres and contacts between them to model the material. DEM modeling of size effect could be advantageous because the development of micro-cracks in the material can be observed and the failure mode can be visualized. The series of experiments were repeated with the model after calibration. The relationship of the parallel bond strength of the contacts and the laboratory compressive strength test was analyzed by aiming to determine a relation between the compressive strength and the bond strength of different sized models. An equation was derived based on Bazant's size effect law to estimate the parallel bond strength of differently sized specimens. The parameters of the equation were optimized based on measurement data using nonlinear least-squares method with SSE (sum of squared errors) objective function. The laboratory test results showed a good agreement with the literature data (compressive strength is decreasing with the increase of the size of the specimen regardless of the shape). The derived estimation models showed strong correlation with the measurement data. The results indicated that the size effect is stronger on concretes with lower strength class due to the higher level of inhomogeneity of the material. It was observed that size effect is more significant on cube specimens than on cylinder samples, which can be caused by the side ratios of the specimens and the size of the purely compressed zone. A limit value for the minimum size of DE model for cubes and cylinder was determined, above which the size effect on compressive strength can be neglected within the investigated size range. The relationship of model size (particle number) and computational time was analyzed and a method to decrease the computational time (number of iterations) of material genesis is proposed.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.2
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• pp.1-7
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• 2018

The purpose of this study was to analyze the energy consumption of Elementary, Middle and High Schools in Daejeon Metropolitan City. The main results are as follow: 1) Annual energy consumption per class was 12,825 (kWh/class) at elementary schools, 15,780 (kWh/class) at middle schools, and 29,447 (kWh/class) at high schools, 2) Generally the smaller the size of the school, the higher the energy consumption per class. However according to the HVAC system there was no consistent pattern of energy consumption per class. 3) According to Box and Whisker's Chart, distribution of energy consumption of elementary and middle schools' had small range. However, the range of high schools increased. 4) Energy consumption in winter season was larger than that of summer season in schools.