• Journal of the Korean institute of surface engineering
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• v.53 no.5
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• pp.227-231
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• 2020

This article investigated the effects of stainless steel plate-patterns bonded to aluminum frypan on the thermal distortion and surface temperature of the frypan during gas or induction heating. Two different stainless steel plate-patterns were employed: type A contains only circular holes and type B has not only circular holes but also vacant spaces of 0.5 mm thick and 40 mm long straight line crossing 60 mm long curved line. The bottom of the frypan was distorted during heating when type A stainless steel plate-bonded frypan while no significant thermal distortion was observed for type B stainless steel plate-bonded frypan during heating. Temperature of the frypan surface showed the same trend during gas heating, irrespective of stainless steel plate-patterns. During induction heating, however, the frypan with type B stainless steel plate-pattern showed lower surface temperature than the frypan with type A stainless steel plate-pattern. It is concluded that Type B stainless steel plate-pattern with circular holes and vacant spaces of lines is very effective for minimizing a thermal distortion and lowering the surface temperature of an aluminum frypan during induction heating.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.3
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• pp.133-142
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• 2011

We produce a photosensitive convex plate to research a Nickel metal relief printing plate using galvanic process. A Method for preparing DLC convex plate that is metalized on Nickel metal relief printing plate using CVD(Chemical Vapor Deposition) process and $N_2DLC$-convex plate that is DLC metalized thin film layer of $N_2$ plasma surface treatment are comprised. DLC thin film layers on Nickel surface are fragile. The results of the research indicate that the coefficient of friction on DLC metalized thin film layer is relatively low than Nickel surface and the durability of Nickel surface coated DLC metalized thin film layer is superior to Nickel surface. A relative evaluation of three form plate wetting properties using varnish liquid-drop plate indicates superior printing aptitudes for $N_2DLC$, DLC, Nichel plate order as above.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.2
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• pp.216-223
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• 2010

The general way to process the surface by means of the laser was heat treatment for strengthening the surface hardness. They have used the laser for changing the property of the surface, especially for metal. Generally, it is recent increasing tendency to use the thin plate panel for making things smaller and lightweight. However, thin plate should be strengthened or let the thin plate panel have moment of inertia by means of engraving the groove or wave on them for lightweight and strengthening. Therefore it is expected that the thin plate panel can be harder and more stable through processing the metal surface by laser beam irradiation and the hardness of thin plate possibly can be also changed how many parts of them are harden. Through this research, it can be grasped how the hardness and mechanical characteristic changes according to width and depth of groove by laser affect the max stress by the ratio of $A_H/A_T$ (hardening area/total area) and characteristic of displacement and structural characteristic for making the thin plate harder by the strengthening metal surface of thin plate by laser through the experiment and analysis of FEA can be presented.

• Journal of the Korean institute of surface engineering
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• v.37 no.2
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• pp.76-79
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• 2004

Nickel chloride coated protein chip plate was developed by using a spin coating method. The ability of histidine tagged protein adsorption was investigated at various solvents. The surface of plate has a large aggregated nickel complex with high density in water. However, the surface of plate has a very small size of aggregated nickel complex with low density in isopropanol. The ability of protein adsorption decreased as increasing the size of alkyl chain in various alcohol solvents. The mechanism on the ability of protein adsorption at the plate surface is discussed.

• Korean Journal of Computational Design and Engineering
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• v.14 no.2
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• pp.129-136
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• 2009

Generally, curved surfaces of ship hull are deformed by flame bending (line heating), multi-press forming, and die-less forming method. The forming methods generate the required in-plane/bending strain or displacement on the flat plate to make the curved surface. Multi-press forming imposes the forced displacements on the flat plate by controlling the position of each pressing points based upon the shape difference between the unfolded flat plate and the curved object shape. The flat plate has been obtained from the unfolding system that is independent of the ship CAD. Apparently, the curved surface and the unfolded-flat surface are expressed by different coordinate systems. Therefore, one of the issues is to find a registration of the unfolded surface and the curved shape for the purpose of minimum amount of forming works by comparing the two surfaces. This paper presents an efficient algorithm to get an optimized registration of two different surfaces in the multi-press forming of ship hull plate forming. The algorithm is based upon the ICP (Iterative Closest Point) algorithm. The algorithm consists of two iterative procedures including a transformation matrix and the closest points to minimize the distance between the unfolded surface and curved surfaces. Thereby the algorithm allows the minimized forming works in ship-hull forming.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2512-2517
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• 2007

Effect of natural convention for hot plate surface temperature uniformity was studied by experiments that were adjusted height of chamber and temperature difference. The hot plate chamber is composed of the hot plate and the upper heater and adiabatic vertical wall. The hot plate diameter is 220mm and maintains temperature at $150^{\circ}C$. Flow pattern compares with surface temperature and confirms that natural convection affects on temperature uniformity of hot plate surface. In case, temperature non-uniformity of hot plate surface is due to heater pattern, lots of weak and small flow cells more improve temperature uniformity than stronger flow cells or non-developing flow cell. Improve temperature uniformity $1.2^{\circ}C$ when developing weak and small flow cells.

• Progress in Superconductivity and Cryogenics
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• v.10 no.2
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• pp.38-41
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• 2008

The relation between surface emissivity and temperature distribution is experimentally and analytically investigated for a conduction-cooled metal plate in vacuum. Experimental set-up consists of a rectangular metal plate placed vertically in a cryostat and thermally anchored to the coldhead of a GM cryocooler at the top. Temperature is measured at a number of locations over the plate with platinum resistors mounted on the plate. A parallel analysis on the balance of heat conduction through the plate and thermal radiation on its surface is performed to numerically calculate the temperature distribution having the same boundary conditions as experiment. By comparing the two results, an average emissivity of the plate is roughly estimated for different metal plates and different surface conditions. The estimated emissivity in present study is less than the listed values for highly polished stainless steel, and meets a fairly good agreement for oxidized copper surface.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.1
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• pp.24-31
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• 2003

In the gas cutting of plate steel, the quality of the cut surfaces and sections is strongly dependent on the cutting conditions such as cutting speed, kerf width, plate thickness, material, distance between tip and specimen, and cutting oxygen pressure etc. The cutting tests of plate steel were carried out using CNC gas cutting machine. This paper deals with cut surface and section characteristics of plate steel in CNC gas cutting. Both top and bottom widths of kerf, the surface roughness(Ra, Rmax) of cutting surfaces are measured under various cutting conditions such as cutting speed, material, distance between tip and specimen, and cutting thickness. The photographs of cut surface and cut section are also analyzed under various cutting conditions.

• Journal of the Korean Geophysical Society
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• v.8 no.1
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• pp.23-33
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• 2005

The digital surface model (DSM) is used for several purposes in photogrammetry, remote sensing and laser scanned data such as orthoimage production, contours erivation, extraction of height information. Creation of a surface model from point-clouds (3-D sparse points) that can be derived from stereo imagery and range data (e.g. laser scanned data) can be done with several mathematical interpolation models. In this paper, thin-plate-spline (TPS) is used for digital surface modeling. Determination of suitable weight is an important problem in thin-plate function for a surface. The Voronoi algorithm has been proposed as a method for determination of the weight in thin-plate-spline. In this paper, methods has been tested for different surfaces. The results show that thin-plate-spline can be independent of weight.

• Journal of the Korean institute of surface engineering
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• v.55 no.3
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• pp.133-142
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• 2022

This paper reviews bipolar plate materials and coatings for polymer electrolyte fuel cell. First, six roles and 10 requirements of the bipolar plate are described in detail. Secondly, type of materials for the bipolar plate and their advantages and disadvantages are mentioned. Thirdly, different metallic materials are introduced in terms of electrical and thermal conductivities, corrosion resistance, weight, strength and cost. Finally, various types of coating materials and methods were briefly reviewed.