• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.58-60
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• 1999

In the industrial field the necessity of the linear motion is increasing. We selected a moving magnet coreless type LDM, which have the advantages, such as long stoke, brushless, no cogging force. Actually, the design is accomplished using FEM analysis for the basic configuration of a magnetic circuit, and characteristic equations for coil design. In the course of design, we have estimated airgap flux density and thrust. We fabricated coreless type LDM and experimented static test. We compared measurement values with FEM analysis values.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.443-451
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• 1991

The solvation numbers of some ions in water and of KCl in mixed solvent systems were measured using the conductometric method. Stoke's radii of ions in solution were calibrated by the Nightingale method and the solvation numbers of ions in mixed solvents were deduced by simple assumptions. The deduced solvation numbers of each solvent reasonably go with its selective properties of solvation. From the isosolvation point of ions, the selective properties of ionic solvation were discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.775-780
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• 2011

This paper represents the study on the development of semi-active bicycle suspension system. The road vibration and transmissibility of front suspension are obtained by driving test on proving ground. The numerical simulation is evaluated by dynamic system modeling and equation of motion. The numerical simulation are performed to estimate the optimal damping force for minimal vibration transmission. And oscillating displacement is calculated and analyzed. Therefore the stoke which convert the damping characteristics is suggested from the driving test and numerical simulation.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.69-79
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• 1997

This paper deals with the measurement and analysis on the scavenging performance of the oppet-valve type two-stroke engine with different shroud system. The scavenging flow characteristics is investigated by flow visualization under steady condition, in which a dye is introduced into single-cycle method using the difference of specific gravity between two working fluids is used to evaluate the scavenging efficiency and the trapping efficiency. The 90° shroud system was found to be the highest efficiency system through both flow visualization and single-cycle test, as well as the shroud system to generally be efficient for reducing a short-circuiting flow during scavenging process in a two-stoke engine.

• Journal of Powder Materials
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• v.19 no.4
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• pp.304-309
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• 2012

The purpose of our study was to develop the fabrication method of porous diatomite ceramics with a porosity gradient by centrifugal molding. The processing variables of centrifugal molding were derived from Stoke's law of sedimentation, which were the radius of the particles, the acceleration due to centrifugal molding and the dynamic viscosity of the slurry. And these could be controlled by ball-milling conditions, centrifugal conditions, and the addition of methyl cellulose, respectively. The effects of processing conditions on the gradient pore structure of diatomite were investigated by particle size analysis, scanning electron microscope, and mercury porosimeter.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.2
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• pp.130-135
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• 1995

In this paper, the numerical simulation of the method of characteristics for a two-stroke SI engine was carried out, and the scavenging efficiency and the performance of single engine with two types of exhaust system, that is, a pipe exhaust system and a tuned exhaust system, were predicted and compared. The conculusions are obtained as follows. (1) The method of characteristics of hometropic flow considering the friction and the variation of area is useful to predict the scavenging efficiency and the performance of the two-stroke engine. (2) The shape of exhaust system effects directly on the scavenging and the trapping efficiency. (3) A tuned exhaust system consisted of the diffuser and the convergent nozzle makes the plugging pulse and therefore enhances the scavenging and the trapping efficiency. (4) It may be possible to design the optimum exhaust system by using the plugging pulse.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.21 no.1
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• pp.22-26
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• 2010

Neuromuscular Disorders Affecting the Larynx are steadily important topics at laryngology. Physiology of larynx is controlled by the frame structure and neuromuscular dynamics to acting on the specialized soft tissue, Therefore, for a proper understanding of the larynx, it is needed the voice and swallowing, a series of prayers on the regulation of neurologic function and the correlation between systemic neuromuscular disease and laryngeal symptoms and clinical knowledge, We described that clinical findings and treatments of the 3 neurological diseases causing dysphonia well (Parkinson's disease, laryngeal tremor, spasmodic dysphonia) and vocal impairments for stoke patients.

• Journal of the Semiconductor & Display Technology
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• v.3 no.2
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• pp.27-33
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• 2004

This paper is concerned with development of a micro tensile testing machine for optical functional materials such as single or poly crystal silicon and nickel film. Two micro tensile testers have been developed for various types of materials and dimensions. One of the testers is actuated by a PZT and the other is actuated by a servo motor for a precise displacement control. The specifications of PZT actuated micro tensile tester developed are as follows: the volumetric size of tester is desktop sized of 710$\times$200$\times$270 $mm^3$; the minimum load capacity and the load resolution in the load cell of 1N are 3 mN and 0.1 mN respectively; the full stroke and the stoke resolution of piezoelectric actuator are 1 mm and 10nm respectively. A special automatic specimen installing equipment is applied in order to prevent unexpected deformation and misalignment of specimens during handling of specimen for testing.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.2
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• pp.150-160
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• 2002

The free vibration characteristics of the triple cylindrical shells filled with fluid are investigated. The triple cylindrical shells are filled with compressible fluid. The boundary condition is clamped at both ends. Analytical method is developed to evaluate natural frequencies of triple cylindrical shells using Sanders' shell theory and courier series expansion by Stokes' transformation. Their results are compared with those of finite element method to verify the validation of the method developed. The modal characteristics of shells filled with fluid at region 1, 2 and 3 are evaluated.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.61-63
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• 2005

In this paper, a new type of permanent magnetic actuator (PMA) with multi-stage coils is proposed. Although the conventional type of PMA has many advantages, it cannot be applied in the high voltage circuit breakers due to its short stoke length. The new type of PMA has long stroke length by using multi-stage coils, so it can be applied as an actuator for the high voltage circuit breakers. Dynamic characteristics are calculated by the finite element method (FEM), equation of electric circuit and dynamic equation. The position of plunger and the current of coils in case of the actuator applied in 38kV, 40kA vacuum circuit breaker are presented.