• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.756-760
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• 2002

This study presents a solution to control a Permanent Magnet Synchronous Motor without sensors. The control method is the presented superposition principle. This method of sensorless theory is very simple to compute estimated angle. Therefore computing time to estimate angle is shorter than other sensorless method. The use of this system yields enhanced operations, fewer system components, lower system cost, energy efficient control system design and increased efficiency. A practical solution is described and results are given in this Study. The performance of a Sensorless architecture allows an intelligent approach to reduce the complete system costs of digital motion control applications using cheaper electrical motors without sensors. This paper deals with an overview of sensorless solutions in PMSM control applications whereby the focus will be the new Controller without sensors and its applications.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.5 s.311
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• pp.60-67
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• 2006

Thermal analysis and prediction of electronic components is required to predict and optimize the reliability of onboard electronic unit employed in space vehicles. This paper introduces a methodology on thermal prediction that uses isothermal PCB model, thermal force model, thermal resistance matrix and superposition principle to calculate electronic devices temperatures undergoing thermal conduction environment. An example is Presented including a prediction result by this method and simulation results performed by commercial program.

• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.120-126
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• 2001

This paper presents a solution to control a PMSM(Permanent Magnet Synchronous Motor) without sensor. The control method is the presented superposition principle. This method of sensorless theory is very simple to compute estimated angle. The use of this system yields enhanced operations, fewer system components, lower system costs, efficient energy control system designs and increased efficiencies. A practical solution is described and its results are given in this study. The performance of a sensorless architecture allows an intelligent approach to reduce the complete system costs of digital motion control applications using the cheaper electrical sensorless motors. This paper deals with an overview of solutions in the sensorless PMSM control applications, whereby the focus will be the new sensorless controller and its applications.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.20-29
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• 1999

The stress field in the body by tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using Boussinesque's potential function. Its validity was proved by saint-venant's principle in remote region of the and in the vicinity of the surface with superposition of point loads.

• KSTLE International Journal
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• v.2 no.1
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• pp.29-34
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• 2001

The stress field in a body caused by the tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using a potential function. The validity of the results of this study was preyed by Saint-Venant's principle in the remote region and by the superposition of point loads in the vicinity of the surface.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.751-754
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• 2000

Stress relaxation experiments were performed to obtain the material properties to be used in the linear viscoelastic study. Master curve of the modulus of polystyrene were obtained by using the time-temperature superposition principle. Because Shyu and Tobolsky's tensile relaxation modulus master curve or Polystyrene material showed very large difference, in-house data were required to calculate the residual stresses in injection-molded products more accurately. Our own experimental data showed that the master curve Shyu's data should be shifted about two orders in material time coordinate.

• Journal of Ocean Engineering and Technology
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• v.16 no.2
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• pp.10-20
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• 2002

본 논문에서는 바다의 자유표면에서 생성되는 항력에 대한 물리적 특성에 대한 연구가 기술되었다. 2차원 파장(Wave Field) 매개변수해석기법(Parametric Analyzing Technique)을 근거로 한 파경계층(Wave Boundary Layer : WBL)의 1차원 모델로서 항력계산과 파경계층의 특성을 추정하였으며 이론의 간략화(Simplifying)에 대한 연구에 주력하였다.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.4
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• pp.1-10
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• 1982

An experimental investigation on the energy absorption of two staged combined structures is presented, which deals with the plastic collapse test as a series of research on soft bow structure involved in a ship collision. The principle of arithmetic superposition of energy absorption is derived upon experimental analysis and based upon the characteristics of the energy absorptions of component structures. This relationship is related to the further approach toward the design of soft bow.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.546-552
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• 2000

Dynamic behavior of laminated composite plates undergoing moderately large deflection is investigated taking into account the viscoelastic behavior of material properties. Based on von Karman's non-linear deformation theory and Boltzmann's superposition principle, non-linear and hereditary type governing equations are derived. Finite element analysis and the method of multiple scales is applied to examine the effect of large amplitude on the dissipative nature of viscoelastic laminated plates.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.565-573
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• 2004

This study is to present explicit analytical expressions for calculating bearing capacity factor $N_{\gamma}$, to provide results of the numerical computation instead of the graphical method. In this study, $N_{\gamma}$ is proposed in the critical failure surface on assumption that the center of log spiral in the radial shear zone can be located at the any points of around footing. The critical failure surface is one which yields minimum passive pressure $P_{\gamma}$ on the radial shear zone from the family of log spirals accoding to change of the center of log spiral. This study adoptes Terzaghi's bearing capacity principle(e.g., Prandtl's mechanism, limit equilibrium equation, superposition principle) but the soil wedge in an elastic zone makes angle $45^{\circ}+{\phi}/2$ with the horizontal and the location of the log spiral's center.