• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.108-116
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• 2003

In this paper, based on the concept of solid particles' sediment problem the working formula determining the bowl length of a Decanter-type centrifuge were derived. Assuming that particles are uniformly distributed along the vertical line of the liquid inlet position, it was possible to derive a constant value k used for determining the bowl length. It was shown from the sample calculations that the bowl length should be increased as the particle size to be removed from the liquid is decreased. The length also should be increased for the same particle size as the bowl diameter is decreased. To help the engineers choose a reasonable bowl diameter, the statistical relationship between the bowl diameter and the capacity of the international products is obtained and presented.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.12
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• pp.1375-1382
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• 2009

The objective of this paper is to apply the load ratio method to the measurement of the crack length of the real scale pipe specimen. The load ratio method was modified and finite element analyses were performed to derive the relationship between the normalized compliance and the normalized crack length for the pipe specimen. In order to measure the crack length, the direct current potential drop method and the modified load ratio method were applied to the pipe test. The applicability of the modified load ratio method was confirmed by comparing the calculated crack length with the measured crack length from the pipe experiment.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.210-216
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• 1998

Taxonomic studies in external morphology, principal component analysis and cluster analysis were conducted to understand the intraspecific relationship among three habitats (Jirisan, Odaesan and Ulleungdo) of allium voctorialis var. platyphyllum. External morphology such as bulb color, leaf blade length and width, petiole length, total leaf length, peduncle length, perianth lobe length and width, length of anther and filament were useful characters for identification of poplations in three habitats. The results obtained based on the principal component (Pc) analysis of treated 72 OTUs(included outgroup) were divided into three groups by the PC 1 ,2,3 and the sums of contributions for the total variance were 84.1%(PC1 51.0%, PC2 24.9% and PC3 8.2%, respectively). In cluster analysis by the UPGMA and Ward's methods , there was similarities in the compostion of clustered taxa, and only Ulleungdo population was distinctly identified from population of other two habitats.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.183-192
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• 1994

Spatial distribution patterns of Antarctic krill, Euphausia superba in the Atlantic Ocean sector were seasonally divided into three or four regions; South George Island, Laurie/Coronation Islands and Livingston/King George Islands. Antarctic krill were caught from the surface to about 150 m in depth. The vertical distribution of catch per hour (CPUE) did not show much differences between the 10 m layers, but there were gradually poorer CPUEs as trawl depth increased. It was estimated from relationship between water temperature and CPUE that the Antarctic krill abundance was maximal at water temperatures of $0.8{\sim}1.0^{\circ}C$. The length compositions of Antarctic krill showed that female fish were, on an average, significantly larger than males. Relationship between carapace length and body length, and body length-body weight relationship were well fitted. Sex ratio was $60.3\%$ for male and $39.7\%$ for female with significant difference at the $5\%$ level.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1163-1170
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• 2009

The clam, Gomphina melanaegis, which is commonly called the sandy beach clam because of its habitat, is a valuable organism in the sandy coast of East Sea, Korea. It is frequently observed in large populations between 0.5 and 5 meters. We have released 50,000 seedling, ranging from the diameter of approximately 3 mm, 2007, and 1,000,000 seedling, ranging from the diameter of approximately 0.2 mm, plus 100,000 adult individuals, ranging from the shell length of approximately 20~40 mm, 2008 at Jinha beach. The spawning period of G. melanaegis, was from June to August, and the main spawning occurred in July. This investigation was carried out to elucidate population distribution on the stocking area of sandy beach clam, G. melanaegis. The relationship between shell length and ring radius in each ring was investigated as a regression line. The relationship between the shell length and shell height of released young clam was SH=1.0105SL-4.7764 ($R^2=0.7905$). The relationship between the shell length and total weight of released young clam was $TW=0.0013SL^{2.3966}$($R^2=0.71$). It draws a deduction that the ring of this clam was produced once a year during the duration between June and August.

• Korean Journal of Applied Biomechanics
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• v.29 no.3
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• pp.173-183
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• 2019

Objective: The aim of this study was to investigate the correlation coefficients between anthropometric parameters of the foot and kinetic variables during running. Method: This study was conducted on 21 healthy young adults (age: $24.8{\pm}2.1yes$, height: $177.2{\pm}5.8cm$, body mass: $73.3{\pm}7.3kg$, foot length: $256.5{\pm}12.3mm$) with normal foot type and heel strike running. To measure the anthropometric parameters, radiographs were taken on the frontal and sagittal planes, and determined the length and width of each segment and the navicular height. Barefoot running was performed at a preferred velocity ($3.0{\pm}0.2m/s$) and a fixed velocity (4.0 m/s) on treadmill (Bertec, USA) in order to measure the kinetic variables. The vertical impact peak force, the vertical active peak force, the braking peak force, the propulsion peak force, the vertical force at mid-stance (vertical ground reaction when the foot is fully landed in mid-stance or at the point where the weight was uniformly distributed on the foot) and the impact loading rate were calculated. Pearson's correlation coefficient was used to investigate the relationship between anthropometric variables and kinetical variables. The significance level was set to ${\alpha}=.05$. Results: At the preferred velocity running, the runner with longer forefoot had lower active force (r=-.448, p=.041) than the runner with short forefoot. At the fixed velocity, as the navicular height increases, the vertical force at full landing moment increases (r= .671, p= .001) and as the rearfoot length increases, the impact loading rate decreases (r=- .469, p= .032). Conclusion: There was a statistically significant difference in the length of fore-foot and rearfoot, and navicular height. Therefore it was conclude that anthropometric properties need to be considered in the foot study. It was expected that the relationship between anthropometric parameters and kinetical variables of foot during running can be used as scientific criteria and data in various fields including performance, injury and equipment development.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.6
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• pp.24-33
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• 2000

This paper investigates the relationship between J-integral and crack tip opening displacement, ${\delta}_t$ using Gordens results of numerical analysis. Estimation were carried out for several strength levels such as ultimate, flow, yield, ultimate-flow, flow-yield stress to determine the influence of strain hardening and the ratio of crack length to width on the $J-{\delta}_t$ relationship. It was found that for SE(B) specimens, the $J-{\delta}_t$ relationship can be applied to relate J to ${\delta}_t$ as follows $J=m_j{\times}{\sigma}_i{\times}{\delta}_t$ where $m_j=1.27773+0.8307({\alpha}/W)$, ${\sigma}_i:{\sigma}_U$, ${\sigma}_{U-F}={\frac{1}{2}} ({\sigma}_U+{\sigma}_F$), ${\sigma}_F$, ${\sigma}_F}$ $Y=({\sigma}_F+{\sigma}_Y)$, ${\sigma}_Y$

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.994-998
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• 2002

• KOREAN JOURNAL OF CROP SCIENCE
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• v.11
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• pp.99-103
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• 1972

In order to clarify the relationship between the characters and the influence of each character on the yield of perilla, correlation coefficients and path coefficients were calculated. The results obtained are summarized as follows; 1. A highly significant positive correlation was found between stem length and stem diameter, number of pods per plant, stem weight, respectively. Number of internodes showed also significant positive correlation , with number of pods per plant, stem weight, respectively as well as the relationship between number of valid branches and number of pods per plant. On the other hand, a significant negative correlation was appeared between number of valid branches and l000-grain weight as well as the relationship between number of pods per plant and l000-grain weight. 2. It seemed to be clear that stem weight, number of pods per plant, l000-grain weight, number of valid branches and stem diameter have direct and positive influence on the yield of perilla. 3. Indirect influence was observed between stem length and stem weight, between number of valid branches and number of pods per plant, and between number of pods per plant and stem weight, respectively. 4. It may be concluded that the yield of perilla is positively correlated with stem length, number of valid branches, number of pods per plant, l000-grain weight and stem weight.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.213-219
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• 1980

Morphological characteristics of the topshell, Turbo cornutus Solander were studied on the basis of shell growth and fatness from April 1978 to October 1979. The Sampled areas were coastal waters of Jeju City, Seongsanpo, Moseulpo and Seogwipo in Jeju. The average shell length of the topshell from Jeju City area was smaller than those of the other three areas, and also the spine number of the 1st row on the shell from Jeju City area was fewer than the others. Sex ratios from each areas represented about 1:1. The relationship between shell length and shell breadth showed regression line and the value of slope for the specimen from Seongsanpo was the lowest. The relationship between shell length and total weight showed exponential curve, and the value was the highest in the specimens from Moseulpo. The value of slope on the relationship between total weight and meat weight was the highest in those from Moseulpo and the lowest from Jeju City. The regression line of relationship between total weight and meat freight in those if Jeju City area showed significant difference from those of the other areas.