• Journal of the Society of Naval Architects of Korea
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• v.41 no.6
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• pp.102-113
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• 2004

A name of 'Sea Ship' and 'River Ship' had been used based on the comprehension for the difference of ship's hull form in Chosun period. We can find a number of literature describing the situation which transferred the cargo from Sea Ship to River Ship because Sea Ship could not go upstream in the river of which the current is fast and the water depth is low. The reason why Sea Ship could not go upstream was that the bottom of Sea Ship was narrow, it means the non-flat bottom. Generally Sea Ship had short length, wide breadth, so L/B of 2.2∼3.0, and high draft and depth. River Ship has long length, narrow breadth, so L/B of 5.0∼6.3, and low draft and the flat bottom in order to adapt to the low water depth of the river.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1128-1138
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• 1990

The mitral valve is not a simple but a complex structure, mitral valve complex. This complex is composed of mitral orifice, annulus, valve leaflet, chordae tendineae and papillary muscles. There were many controversies about this structures. We studied mitral valve complex in 63 cases of normal Korean adults, such as the circumference of mitral annulus, the intercommissural diameter, height and breadth of the cusps, including commissure, the ratio of rough to clear zone, breadth of the achordal zone, the number of scallops of posterior cusp, the number, length and the pattern of arrangement of the several types of chordae, the number and morphological characteristics of papillary muscles.

• Fisheries and Aquatic Sciences
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• v.7 no.2
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• pp.84-89
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• 2004

Feeding habits of Sillago japonica collected from in an eelgrass (Zostera marina) bed in Jindong Bay, Korea were studied. S. japonica was a carnivore which consumed mainly gammarid amphipods, polychaetes, bivalves, caridean shrimps and crabs. Its diets also included a small amount of fishes, copepods and caprellid amphipods. The diet of S. japonica underwent significant size-related changes; small individuals (<5cm SL) fed mainly on gammarid amphipods and crab larvae, while proportion of polychaetes and bivalves increased with increasing fish size and gammarid amphipods were also important prey for medium size individuals (5.1-9.9cm SL). The large individuals (>10cm SL) ate polychaetes, caridean shrimps and crabs. The dietary breadth of S. japonica were varied with size. The diet of S. japonica also underwent seasonal changes that could be related to differences in prey availability; gammarid amphipods were mainly consumed in spring and polychaetes in summer.

• The Research Journal of the Costume Culture
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• v.12 no.6 s.53
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• pp.897-907
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• 2004

The aim of this study is provide fundamental data on the glove size and pattern-making. The study was conducted targeting 60 men and 271 women whose age were within the limits 18-35 in Seoul and the neighboring districts. A total of 90 features in the right hand wew used for the anthropometric measurement and analysis using anthropometry and photometry. The result show that there was a difference between men and women' hand. And the result of correlation analysis between hand factors, length factor related to length and depth factors, breadth factor related to breadth and circumference factors. The sailing glove size in Korea was not suitable to Index finger circumference at 1st Phalanx and Middle finger length.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.185-190
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• 2000

The effect of specimen thickness and notch's depth and the validity of J-integral analysis were studied on the fracture behavior of concrete. Through the 3-point bending test, the stress-deformation curves were experimentally measured. Concrete fracture toughness is calculated from stress-displacement curves. Concrete fracture toughness decreases when notch's depth is longer. So, Gf is less sensitive than JIc and Gf is more useful factor as concrete fracture toughness parameter. The values of J-integral and fracture energy increase when the breadth of concrete specimen get longer from 75mm to 150mm. Therefore, the breadth effect of specimen has to be considered in determining the concrete fracture toughness.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.14-21
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• 2001

To estimate crack growth rate and cycle ratio uniquely, many investigators have developed various kinds of mechanical parameters and theories. But, thes have produced local solution space through single parameter. Neural Networks can perform patten classification using several input and output parameters. Fatigue damage model by neural networks was used to recognize the relation between da/dN/N/N(sub)f, and half-value breadth ratio B/Bo, fractal dimension D(sub)f, and fracture mechanical parameters in 2024-T3 aluminium alloy. Learned neural networks has ability to predict both crack growth rate da/dN and cycly ratio /N/N(sub)f within engineering estimated mean error(5%).

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.89-94
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• 2002

A commercial CFD code is used to calculate the 3-D viscous flow field within the centrifugal pump impeller. Design conditions are changed by impeller inlet(9.3mm, 12.2mm) and outlet breadth(6.65mm, 6.85mm). Numerical calculation was performed by changing flow rate from 8 to 26m$^{3}$/hr. Computation results shows that total head is increased at the larger inlet and outlet breadth than the others. And when the flow rate is increasing, the total head was decreased. The maximum efficiency of pump is shown at the design flow rate(16m$^{3}$/hr). In this study shows that the calculated results are good agreements with analysis results of design condition.

• Tribology and Lubricants
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• v.10 no.3
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• pp.71-77
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• 1994

Rolling friction test was carried out to investigate the effect of the wear amount on rolling contact fatigue process in lubrication oil. The methods of this process were conducted at two Hertzian contact pressure and three slide ratio in each case by employing normalized and annealed carbon steel. During process of the rolling contact fatigue, the number of rotation until surface damage was occurred, the wear amount of rolling contact surface, and residual stress and half-value breadth using X-ray reflection on rolling contact surface were investigated. The result of this study shows that rolling contact fatigue process was directly influenced by wear trend and was confirmed by change of residual stress and half-value breadth on rolling contact surface.

• Tribology and Lubricants
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• v.17 no.3
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• pp.209-215
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• 2001

In view of the effects of the hardness of material on fatigue, rolling contact fatigue process in hard metals seems to differ from it in soft metals. This paper has been aimed to compare the rolling contact fatigue process according to the hardness of materials. Rolling contact fatigue tests using the ball bearings assembled with the inner race of four different hardness have been carried out. In addition, residual stress and half-value breadth on/below the inner raceway during individual rolling contact fatigue have been measured by X-ray diffraction. The results of this study showed that the change of residual stress and half-value breadth during the rolling contact fatigue on race way in hard metals is the same as in soft metals. However, plastic deformation by rolling contact in hard metals is in microscopic scale but only for soft metals in macroscopic scale.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.358-367
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• 2010

Feeding habits of Acentrogobius pellidebilis collected from in an eelgrass(Zostera marina) bed from January to December 2006 were studied. A. pellidebilis ranged form 1.6 to 6.9 cm in standard length were determined. A. pellidebilis was a carnivore which consumed mainly copepods, polychaetes, and amphipods. Its diets included small quantities of isopods, seaweeds, nematods, and gastropods. It showed ontogenetic changes in feeding habits. Smaller individuals (<2.0cm SL) fed mainly on copepods. While the consumption of copepods decreased with increasing fish size, the consumption of polychaetes and amphipods were increased. Dietary breadth index was varied with fish size.