• Journal of Korea Multimedia Society
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• v.6 no.6
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• pp.985-990
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• 2003

This paper presents the representation and its shape analysis of face by features based on surface curvature estimation and proposed rotation vector of the human face. Curvature-based surface features are well suited to use for experimenting the 3D human face segmentation. Human surfaces are exactly extracted and computed with parameters and rotated by using active surface mesh model. The estimated features were tested and segmented by reconstructing surfaces from the face surface and analytically computing Gaussian (K) and mean (H) curvatures without threshold.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.15-20
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• 1992

This paper outlines the methods of visualizing 3-dimensional free form surfaces employing the Painter's algorithm, especially for the ship hull forms which are defined as open uniform Bi-cubic B-spline surfaces. The computer graphic codes are developed for the transparent wire-frame, the hidden surface removal and the shading visualization techniques, The codes are applied to the ship hull 3-dimensional surface visualization and the color graphic figures are displayed. Also Gaussian curvature is displayed on the color plots of the isoparametric net of the ship hull surface.

• Proceedings of the KIEE Conference
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• summer
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• pp.1109-1111
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• 2004

This paper deals with the calculation of contact resistance depending on the applied force by modeling surface roughness. The true contact surface area is made up of many asperities of varying heights which is close to Gaussian distribution. The mean square deviation and the mean value of the Gaussian distributed asperity heights were determined in this paper. The elastic deformation of the surface asperities according to the increasing of applied force were considered. The contact resistance was also calculated by using the Greenwood analysis.

• Wind and Structures
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• v.28 no.5
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• pp.315-329
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• 2019

Non-synoptic winds have distinctive statistical properties compared to synoptic winds and can produce different wind loads on buildings and structures. The current study uses the new capabilities of the WindEEE Dome at Western University to replicate a stationary non-Gaussian wind event recorded at the Port of La Spezia in Italy. These stationary non-Gaussian wind events are also known as intermediate wind events as they differ from non-stationary non-Gaussian events (e.g., downbursts) as well as stationary Gaussian events (e.g., atmospheric boundary layer (ABL) flows). In the present study, the wind loads on a typical low-rise building are investigated for an intermediate wind event reproduced using a continuous radial impinging jet (IJ) at the WindEEE Dome. For the same building model, differences in wind loads between ABL and IJ are also examined. Wind loads on different surface zones on the building, as defined in the ASCE code for design loads, are also calculated and compared with the code.

• Journal of the Korean Geotechnical Society
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• v.37 no.10
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• pp.55-63
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• 2021

The construction of shield tunnels is being expanded from the small-bore tunnels such as power, telecommunications, water supply, and sewerage pipes to the large bore tunnels such as road and railway tunnels with the advancement of the shield TBM (Tunnel Boring Machine) manufacturing technology. Accordingly, the construction of twin shield tunnels is increasing. Peck (1969) reported that the surface settlement trough is well described by a Gaussian distribution on a single shield tunnel. Hereafter, many studies about the surface settlement trough were performed by the field measurement, laboratory model test, and numerical analysis. This study confirmed that the additional surface settlement trough induced by the 2^nd tunneling were well described by using each Gaussian curve for the right and left sides of the settlement trough.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.64-72
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• 1993

Analytical models for the prediction of the size of hardened zone in laser surface hardening are presented. The models are based on the solutions to the problem of three-dimensional heat flow in plates with infinite thickness. The validity of the model was tested on medium carbon steel for Gaussian mode of beam. Then the model for rectagular beam was used for the predicition of the size of hardened zone on various hardening process parameters. From the calculation results it appeared that the size and shape of the hardened zone are strongly dependent on process parameters such as beam mode, beam size, and traverse speed.

• Honam Mathematical Journal
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• v.46 no.1
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• pp.12-37
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• 2024

The paper introduces a set of new ruled surfaces such that the base curve is taken to be the striction curve of N, C and W ruled surfaces from the alternative frame, and the generating line is taken to be one of the vectors of Sannia frame. The characterizations for each ruled surface such as fundamental forms, the Gaussian and mean curvature are also examined to provide the conditions for each surface to be developable or minimal.

• Journal of Korean Society of Disaster and Security
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• v.6 no.2
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• pp.1-8
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• 2013

This study is concerned with the estimation of fluctuate wind velocity statistic properties in the major cities reflecting the recent meteorological with largest data samples (yearly 2003-2012). The basic wind speeds were standardized homogeneously to the surface roughness category C, and to 10m above the ground surface. The estimation of the extreme of non-Gaussian load effects for design applications has often been treated tacitly by invoking a conventional wind design (gust load peak factor) on the basis of Gaussian processes. This assumption breaks down when the loading processes exhibits non-Gaussianity, in which a conventional wind design yields relatively non conservative estimates because of failure to include long tail regions inherent to non-Gaussian processes. This study seeks to ascertain the probability distribution function from recently wind data with effected typhoon & maximum instantaneous wind speed.

• Journal of Welding and Joining
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• v.25 no.3
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• pp.78-84
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• 2007

Laser Material Processing has been replaced the conventional machining systems - cutting, drilling, welding and surface modification and so on. Especially, LTH(Laser Transformation Hardening) process is one branch of the laser surface modification process. Conventionally, some techniques like a gas carburizing and nitriding as well as induction and torch heating have been used to harden the carbon steels. But these methods not only request post-machining resulted from a deformation but also have complex processing procedures. Besides, LTH process has some merits as : 1. It is easy to control the case depth because of output(laser power) adjustability. 2. It is able to harden the localized and complicated a.ea and minimize a deformation due to a unique property of a localized heat source. 3. An additional cooling medium is not required due to self quenching. 4. A prominent hardening results can be obtained. This study is related to the surface hardening of the rod-shaped carbon steel applied to the lathe based complex processing mechanism, a basic behavior of surface hardening, hardness distribution and structural characteristics in the hardened zone.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.1
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• pp.1-11
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• 1991

When a geometric modeling of a hull form for ship design and hull production is done, a hull fairing is a tedious process which wastes a lot of time, but it is unavoidable because hull consist of the sculptured surfaces. This paper presents the mathematical method of the direct fairing to overcome the tediousness of cross fairing. Bi-cubic B-spline surface description was adopted for the representation of the hull surface. The fairing process was executed by minimizing the strain energy in a shell plate. The color-encoded Gaussian curvature and strain energy were visualized on the screen to illustrate the fairness of the surface. The geometric information generated from the faired hull surface model was interfaced with the basic design calculation package and the hull production system.