• Structural Engineering and Mechanics
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• v.3 no.4
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• pp.359-372
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• 1995

This study presents an efficient method for optimum design of plate and shell structures, when the design variables are continuous or discrete. Both sizing and shape design variables are considered. First the structural responses such as element forces are approximated in terms of some intermediate variables. By substituting these approximate relations into the original design problem, an explicit nonlinear approximate design task with high quality approximation is achieved. This problem with continuous variables, can be solved by means of numerical optimization techniques very efficiently, the results of which are then used for discrete variable optimization. Now, the approximate problem is converted into a sequence of second level approximation problems of separable form and each of which is solved by a dual strategy with discrete design variables. The approach is efficient in terms of the number of required structural analyses, as well as the overall computational cost of optimization. Examples are offered and compared with other methods to demonstrate the features of the proposed method.

• Journal of Multimedia Information System
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• v.1 no.2
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• pp.119-126
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• 2014

We propose a bicycle detection system riding on people based on modified projected local binary pattern(PLBP) for vision based intelligent vehicles. Projection method has robustness for rotation invariant and reducing dimensionality for original image. The features of Local binary pattern(LBP) are fast to compute and simple to implement for object recognition and texture classification area. Moreover, We use uniform pattern to remove the noise. This paper suggests that modified LBP method and projection vector having different weighting values according to the local shape and area in the image. Also our system maintains the simplicity of evaluation of traditional formulation while being more discriminative. Our experimental results show that a bicycle and motorcycle riding on people detection system based on proposed PLBP features achieve higher detection accuracy rate than traditional features.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.71-73
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• 2012

With numerical simulations, this study investigated the combustion and heat transfer of three different coals under air- and oxy-fuel combustion in a 100 MWe boiler. The boiler is retrofitted to an opposed-firing type while maintain the original furnace shape of downshot firing. The boiler achieved good combustion in both combustion modes for three coals tested. However, the contribution of gasification reactions by $CO_2$ and $H_2O$ significantly increased due to the lack of gaseous mixing. This was different from a typical front-wall firing boiler, which showed larger contribution of char oxidation during air-coal combustion. The wall heat flux was lower in oxy-coal mode at a $O_2$ level of 27%, which has to be considered in further development of the process.

• Journal of the Korean Vacuum Society
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• v.8 no.4A
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• pp.476-481
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• 1999

Characteristics of platinum dry etching were investigated in a cryogenic magnetized inductively coupled plasma (MICP). The problem with platinum etching is the redeposition of sputtered platinum on the sidewall. Because of the redeposits on the sidewall, the etching of patterned platinum structure produces feature sizes that exceed the original dimension of the PR size and the etch profile has needle-like shape [1]. The main object of this study was to investigate a new process technology for fence-free Pt etching As bias voltage increased, the height of fence was reduced. In cryogenic etching, the height of fence was reduced to 20% at-$190^{\circ}C$ compared with that of room temperature, however the etch profile was not still fence-free. In Ar/$SF_6$ Plasma, fence-free Pt etching was possible. As the ratio of $SF_6$ gas flow is more than 14% of total gas flow, the etch profile had no fence. Chemical reaction seemed to take place in the etch process.

• Transactions of Materials Processing
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• v.10 no.7
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• pp.551-557
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• 2001

In the present study, several design parameters of the flat-die extrusion process are investigated using the finite element method. The effects of the location of an extrusion profile, arrangement of multiple extrusion profiles, and the design of various die land have been investigated through the analysis. Several numerical examples of flat-die extrusion of such as C-section, multiple U-shape, and a window guide section, are analyzed. From the comparative study, the effect of design parameters is investigated. In each example, comparing the velocity distribution with that of the original design, it has been shown that the design modification affords more uniform distribution.

• Korean Journal of Computational Design and Engineering
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• v.4 no.2
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• pp.127-138
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• 1999

For reverse engineering, curves and surfaces are modeled for new products by interpolating the digitized data points. But there are many measuring or deviation errors. Therefore, it is important to handle errors during the curve or surface modeling. If the errors are ignored, designer could get undesirable results. For this reason, fairing procedure with the aesthetics criteria is necessary in computer modeling. This paper presents methods of 3D NURBS curve fairing. The techniques are based on automatic repositioning of the digitized dat points or the NURBS curve control points by a constrained nonlinear optimization algorithm. The objective function is derived variously by derived curved. Constraints are distance measures between the original and the modified digitized data points. Changes I curve shape are analyzed by illustrations of curve shapes, and continuous plotting of curvature and torsion.

• Korean Journal of Computational Design and Engineering
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• v.16 no.5
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• pp.344-350
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• 2011

In injection molding industries, CAE analyses are generally used to find out problems predicted during the process of manufacturing. The results of CAE analyses consist of much in formation such as meshes and stress, so that the size of data is pretty large. To reduce the size of the data and to make it easy to share, the CAE result to JT translator is proposed in this paper. The translator consists of three modules to translate CAE result to JT format; Extracting module gets ASCII data of product shape and the result values of CAE analysis. Sorting module and mapping module make an element data set and JT file with the data extracted from Extracting module respectively. To the JT files, engineers are able to append product properties and their comments, so that they can share the whole history of the analysis process. In addition, our case study shows that the size of JT format is reduced by almost 90% of its original data format.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.141-147
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• 2016

Background: A project for building a neutron time-of-flight (nTOF) facility is progressing. We expect that the construction will start in early 2016. Before that, a detailed simulation based on the current architectural drawings was performed to optimize the performance of our facility. Materials and Methods: Currently, several parts had been modified or changed from the original design to reflect requirements such as the layout of the electron beam line, shape of the vacuum chamber producing a neutron beam, and the underground layout of the nTOF facility. Detailed analysis for these modifications has been done with MCNP simulation. Results and Discussion: An overview of our photo-neutron source and KAERI nTOF facility were introduced. The numerical simulations for heat deposition, source term, and radiation shielding of KAERI nTOF facility were performed and the results are discussed. Conclusion: We are expecting that the construction of the KAERI nTOF facility will start in early 2016, and these results will be used as basic data.

• The Journal of the Korean dental association
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• v.12 no.9
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• pp.691-694
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• 1974

The trends of restoration on abrased teethis mostly based on gnathology or on practical experience. This study was performed on plaster models from 60 young men whose teeth and occlusion are clinically normal. A pair, upper and lower models, were mounted on HANAU articulator. Iron ball bearing 0.2mm 0.5mm 0.7mm and 1.0mm in diameter was attached on mesiobuccal cusp of upper first molar. [table I] Long ribbon shape of cold cure resin was inserted and jaw was closed gently so as not to move disturb original position of iron ball. The resin bite registration was measured minimun thickness from each lingual cusps of upper jaw and buccal cusps of lower jaw by means of Bowley gauge. The results were as follows (graph). 1) The distance from upper lingual cusps and lower buccal cusps: backward cusps showed smaller than standard cusp (upper mesio-buccal cusp) and forward cusps showed longer than standard. 2) The measurements from upper lingual cusps are not coincide with lower buccal cusps.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.3
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• pp.1-8
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• 2004

The purpose of this study was to investigate gather as decoration techniques of clothes. In this study, we defined 21st century as the modern fashion. And analyzed design that applied gather concerned with Milan, New York, London, Paris, Tokyo Woman's Collections. Data were used from Fashion News and Gap Press Magazine (2001-2004). The results of this study were as follows: 1. Gather was the most original techniques among decoration techniques of clothes and formed three-dimensional space. 2. There were many kinds of gather such as cluster gather, all gather, shirring, smoking, frill, flounce, ruffle. and it gave a different impression with Fabrics, cutting method, sewing method, parts that were used. 3. Gather had practical functions providing enough space in activity and was presented as new shape by three-dimension body motion when it was put on. 4. After analyzing design that applied gather showed in collections, there were various appearance according to designer's sensitivity.