• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.106-109
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• 1991

A magnet is designed and analysed using a finite element method program (FLUX2D), which will be employed to the 2-module MAGLEV test vehicle for developing of DAE JEON EXPO '93 Magnetic Levitation System. Levitation force. guidance force and thermal characteristics are examined according to the variation of parameters of the magnet ie. pole width, window area, rail configuration, input current and so on. An optimal geometry of the magnet are provided.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1792-1797
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• 2007

This paper try to find root-cause of failure in a connector used in transmitting signals for throttle body control in automotives by analyzing possible failure causes and performing experiments to simulate the cable failure in field. The connector comprises fins, wires, and case moldings. The failure is due to degradation of initial clamping force required fixing fins and wires in the connector. Expansion and compression of the case molding material surrounding fins would cause the degradation. Investigations of strict initial claming force and control of thermal expansion property of the molding are required to prevent the failure.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.5
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• pp.39-45
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• 2012

For a fundamental study for high concentration pigment coating, the effects of alkali swellable emulsion (ASE) type rheology modifier and surface adsorption emulsion (SAE) type rheology modifier on both the stability and the viscoelastic behavior of a coating color were elucidated. The coating color prepared with SAE type rheology modifier showed superior thermal and mechanical stability than that with ASE type. In the high concentration and high speed coating process, the mechanical stability of a coating color was a key parameter since both impact force and shear force were increased with the increase of coating color concentration and coating speed, respectively.

• Nuclear Engineering and Technology
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• v.30 no.1
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• pp.17-25
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• 1998

Transport of carbon and boron impurity ions parallel to magnetic field lines in the tokamak SOL (scrape-off layer) is numerically investigated for a one-dimensional steady state. The spatial distributions of density and velocity of the impurity ions in a steady state are calculated by finite difference method for a single-fluid model. The calculated results show that among forces acting on SOL particles thermal force produced tv plasma temperature gradient is a principal force determining the feature of impurity distribution profiles in the tokamak edge. However, strong collisional friction forces appearing dominant in front of the diverter plate restrain impurity ion flows due to temperature gradients from moving toward the midplane. Consequently, the stagnation point develops in the impurity flow by these two forces near the diverter region, in which ion flows change their directions. Impurity ions turn out to be accumulated at the stagnation points, where peaked profiles of highly-ionized state ions are relatively predominant over those of low-ionized state ions.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.3
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• pp.153-162
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• 1987

The purpose of this paper is to analysis and develop theoretically the characteristics of tubular linear induction motor, which is a special industrial motor that generates directly thrust force from electrical power. The Poisson equation about vector potential which is created by the application of Maxwell electromagnetic equation with the speed considered, results in modified Bessel equation by the assumption that is applied to each region of the experimental motor. Vector potential, magnetic flux density, secondary current, and thrust force according to its region respectively were found out by substituting boundary condition for this equation and rearranging. Besides, a attendant materials, that is, thermal characteristic, which is one of the characteristics under the operation of experimental motor each part's magnetic flux distribution characteristics within active zone, the required time for reciprocating motion, and variation of power factor vs. a slip were found.

• Journal of the Korean Ceramic Society
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• v.19 no.3
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• pp.223-228
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• 1982

For the preparation of ferroxidure BaO.5.5 $Fe_2O_3$ with high coercive force, the green and calcined coprecipitates, which were obtained by neutralizing the mixed salt solution $FeCl_2-BaCl_2$ and $FeCl_3-BaCl_2$ with alkali solution $NaOH-Na_2CO_3$, were investigated about the thermal reaction, crystal growth, and the magnetic properties of the sintered specimens. The very single-domain crystallites of Ba-ferrite with high coercive force are formed from the coprecipitate of amorphous $Fe(OH)_3$ and amorphous $BaCO_3$ at lower temperature than that of subnucleus crystalline $\delta$-FeOOH and amorphous $BaCO_3$.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.6
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• pp.8-13
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• 2003

CFRP composite has a lot of merits such as mechanical characteristic, light weight and thermal resistance. For these merits CFRP is applied to so many industrial area. In order for the composite materials to be used in the aircraft structures or machine elements, accurate surfaces for bearing mounting or joints must be provided, which require precise machining. In this paper, the relationship between the stack thickness and drill diameter is examined from the drilling experiment, which is the drilling of 16, 32, 48p1ies specimen with the ${\phi}8$, ${\phi}10$, ${\phi}12mm$ cemented carbide drill. The results are analyzed with consideration of cutting force, stack thickness and drill diameter.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.125-128
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• 1997

They use a Ball End-mill in order to manufacturing sculptured surface when making metal mold, mold, cars and aircraft. In the work of a Ball End-mill case, customers do not often satisfied with manufacturing precision. Eventually, they have to re-work for the purpose of meeting manufacturing precision. There are resulted in lots of loss, whereby, in terms of both time and costs. The reasons of tolerance reducing manufacturing precision are thermal strain, the surface is damaged because of increasing cutting force and tool wear, tool deflection etc.. We focus on, however, manufacturing precision caused due to deflection of tool.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.3
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• pp.47-50
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• 2006

High-speed machining is a very useful tool and one of the most effective rapid manufacturing processes. This study sought to produce various high-speed machining materials with excellent quality and dimensional accuracy. However, high-speed machining is not suitable for microscale thin-walled structures because the structure stiffness lacks the ability to resist the cutting force. This paper proposes a new method that is able to rapidly produce very thin-walled structures. This method consists of high-speed machining followed by filling. A strong work-holding force results from the solidification of the filling materials. Low-melting point metal alloys are used to minimize the thermal effects during phase changes and to hold the arbitrarily shaped thin-walled structures quickly during the high-speed machining. We demonstrate some applications, such as thin-walled cylinders and hemispherical shells, to verify the usefulness of this method and compare the analyzed dimensional accuracy of typical parts of the structures.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.190-195
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• 2003

CFRP composite has a lot of merits such as mechanical characteristic, light weight, and thermal resistance. For these merits CFRP is applied to so many industrial area. In this paper, the relationship between the stack thickness and drill diameter is examined from the drilling experiment, which is the drilling of 16, 32, 48 plies specimen with the $\phi$8, $\phi$10, $\phi$12mm cemented carbide drill. The results are analyzed with consideration of cutting force, stack thickness and drill diameter.