• Journal of Advanced Marine Engineering and Technology
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• v.24 no.2
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• pp.82-89
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• 2000

Edge detection is the first step and very important step in image analysis. In this paper, proposed edge detection operators based on informations of edge types and it is different from other classical edge detection operators such as gradient and surface fitting operators. The first, we defined characteristics of edge types such as localization, thinness, length. The second, we defined valid edge types and ideal edge pixel positions in $3\times3$window based on edge characteristics of edge types. And we proposed edge detection algorithm and twelve windows based on valid edge types. In specially, proposed algorithm was shown better performence of edge detection than other operators such as gradient operator and the LoG(Laplacian of Gaussian) operator of zero crossings.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.64.2-64.2
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• 2014

Interacting galaxy pairs are important for study of galaxy evolution. We selected 8,542 interacting galaxy pairs out of 593,514 KIAS-VAGC galaxy sample with 0.02 < z < 0.047 and r_mag <17.6. We then classified by their interacting features into 6 types by visual inspection. We focused on two types whose spiral tidal features extend to the center of early type galaxy (ETG) or to the edge of ETG. We compared galactic parameters of these two types with those of entire 8,542 pairs as well as between the two types. Preliminary result shows both types are very close pairs (projected distance ~ 20 kpc). Spiral galaxies in the center type are more massive but less bright than those in edge type. ETGs in the edge type are brighter but not more massive than those in the center type. The center type has a mass ratio 3.4 times greater than the edge type, but the edge type has a higher angular momentum than the center type.

• Structural Engineering and Mechanics
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• v.61 no.2
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• pp.255-266
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• 2017

In this study, self-supporting roofing elements especially convenient for large-span structures such as stadium, airport terminal, mall, coliseum, etc. were examined with respect to critical buckling load. These elements were assumed as laminated composite plates and, variation of free-edge forms, cutout types and lamination configurations were used as design parameters. Based on the architectural feature and structural requirements, the effects of curvilinear free-edge form on critical buckling load were focused on in this research. Within this scope, 14 types of lamination configuration were specified according to various orientation angle, number and thickness of plies with a constant value of total plate thickness. Besides that, 6 different types of cutout and 3 different free-edge forms were determined. By combining all these parameters 294 different critical buckling load analyses were performed by using ANSYS Mechanical software based on finite element method. Effects of those parameters on critical buckling load were evaluated referring to the obtained results. According to the results presented here, it may be concluded that lamination conditions have more significant influence on the critical buckling load values than the other parameters. On the other hand, it is perceived that curvilinear free-edge forms explicitly undergo changings depending on lamination conditions. For future work, existence of delamination might be considered and progression of the defect could be investigated by using non-linear analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.49-52
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• 2008

The numerical analysis for gas temperature of turbine blade surface has been performed to investigate development of temperature with various blade edge shape. Two different types of the turbine which one is "Sharp" edge and the other is "Round" edge was modeled. Computations have been carried out several turbine rotational speeds in the range from 0 to 10,000 rpm for the each types of turbine edge shape. As a result, the more rotational speed of turbine increased, the more turbine blade's temperature decreased. It is also found that the surface temperature of turbine blades for sharp type edge were lower than the round type edge.

• The Korean Journal of Zoology
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• v.3 no.1
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• pp.13-18
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• 1960

1. Author has surveyed the frequency, geographic variation and micro-geographic variation of the elytral pattern types and the elytral edge of the population of lady-beetle, Harmonia axyridis Pallace which was collected in Seoul and the other 6 localities in Korea. 2. The number of specimen collected were 3.051 in which succinea occupied 88.32 % : Axyridis, 1.00% : spectabilis, 6.145 : and Conspicua , 4.545. 3. Of all 84.80% were found to have elytral edge. 4. There was a little difference in compositional proportation of the above four types to population and in the frequency of elytral edge between the population of west seaside and that of inland of Korea. 5. An interesting micro-geographic variation was observed in Dae-Chun, a beach located on west seaside of south Korea. In this locality , the Succinea occupied 45.23% and 27.805 were found to be provided with elytral edge in the specimen collected in pine trees ( Pinus thunbergii Parlatore), while in the specimen collected in burley field, oak, willow etc. 92.00% were Succinea and 90.93% were found to have elytral edge.

• The Korean Journal of Zoology
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• v.8 no.1
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• pp.8-10
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• 1965

1. We have observed the frequency , geographi variation and microgeographic variation of the elytral pattern types and the elytral edge of the population of Lady-beetle, Harmonia axyridis PALLACE, collected in Jinju and other 6 localitites in South Korea. 2. the number of specimen collected were 6,625 in which Succinea was 90.32% : Axyridis ; 0.74% : Spectabilis , 3.82% ; and Conspicua 5.07%. 3. We have found that 92.26% of all specimens have elytral edge. 4. There were some differences in the compositional of the elytral pattern types and elytral edge to the population among the Western seaside , inland and southern seaside of South Korea , whereas as great difference was in the compositional proportion tot he population of Spectabilis between the western and southern seaside . There was also a gret difference of the elytral edge between the inland and southern seaside. 5. A micro-geographic variation was observed in Jinju , located on southern area of South Korea. In the samples collected from the pine trees at Jinju area the Succinea occupied 73.25%, and 69.61 % were found to be provided with elytral edge, while in the general population 92.46% of specimen were Succinea and 98.35% were found to have elytral edge.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.159-163
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• 2009

In this paper, the fluid dynamic forces and performances of a moving airfoil in the low Reynolds number flow is addressed. In order to calculate the necessary propulsive force for the moving airfoil in a low Reynolds number flow, a lattice-Boltzmann method is used. The critical Reynolds and Strouhal numbers for the thrust generation are investigated for the four propulsion types. It was found that the Normal P&D type produces the largest thrust with highest efficiency among the investigated types. The leading edge of the airfoil has an effect of deciding the force production types, whereas the trailing edge of the airfoil plays an important role in augmenting or reducing the instability produced by the leading edge oscillation. It is believed that present results can be used to decide the optimal propulsion devices for the given Reynolds number flow.

• Korean Journal of Environment and Ecology
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• v.4 no.1
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• pp.44-50
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• 1990

To investigate edge vegetation structure in the Mt. Sokri National Park, field survey was executed in August. 1990 and the result are as follows. Dominant edge species by crown-layer and smilarity of species composition seemed to be affected by existing upper layer vegetation, altitude aspect and physiographical location. and the edge vegetation at summit was severely different with one of the other environmental types. Species diversity of edge vegetation was highest at Northern midslope, lowest at Southern mid-slope. and Acer pseudo-sieboldiamun var. koreanum was appeared as a dominant species at all environmental types. Frequency classes of edge species were different by altitude, aspect, physiographicallocation. Acer pseudo-sieboldiamun var, koreanum, Quercus mongolica, Fraxinus rhynchophylla, Lespedeza maximowiczii, Weigela subsessilis showed high frequency class at all environmental condition.

• Computers and Concrete
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• v.32 no.5
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• pp.499-511
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• 2023

Anchor channels are commonly used for façade, tunnel, and structural connections. These connections encounter various types of loadings during their service life, including high rate or impact loading. For anchor channels that are placed close and parallel to an edge and loaded in shear perpendicular to and towards the edge, the failure is often governed by concrete edge breakout. This study investigates the transverse shear behavior of the anchor channels under quasi-static and high rate loadings using a numerical approach (3D finite element analysis) utilizing a rate-sensitive microplane model for concrete as constitutive law. Following the validation of the numerical model against a test performed under quasi-static loading, the rate-sensitive static, and rate-sensitive dynamic analyses are performed for various displacement loading rates varying from moderately high to impact. The increment in resistance due to the high loading rate is evaluated using the dynamic increase factor (DIF). Furthermore, it is shown that the failure mode of the anchor channel changes from global concrete edge failure to local concrete crushing due to the activation of structural inertia at high displacement loading rates. The research outcomes could be valuable for application in various types of connection systems where a high rate of loading is expected.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.2
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• pp.73-79
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• 2000

The part-surface of mold or stamping-dies consists of a compound surface which consists of lots of composite surfaces, and may have various types of feature shapes including convex sharp edge (CSE). Those CSE features should be considered with care in machining the surface, which necessitates extraction of CSE curves on a compound surface. This work can be done rather easily for a solid model which has a complete topology information. In case of the compound surface without topology information, however, such CSE curves must be gathered through some geometrical calculations paying much computation time. In the paper, extracting CSE curves by the construction of a CSE region-map which can reduce time, and detecting various common edge types are presented.