• Korean Journal of Materials Research
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• v.23 no.8
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• pp.462-468
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• 2013

We study and describe-from the point of view of the interactions of the adsorbed particles-three types of the adsorption isotherms, namely, Langmuir type adsorption isotherms, phase transition type adsorption isotherms, and adsorption limited type adsorption isotherms, which are observed by experiments. By introducing and using a one dimensional statistical occupancy model, we derived analytical adsorption isotherms for the no force, the attractive force, and the repulsive force exerted on the other adsorbed particles. Our derived adsorption isotherms qualitatively pretty well agree with the experimental results of the adsorption isotherms. To specify each adsorption type, Langmuir type adsorption is a phenomenon that occurs with no forces between the adsorbed particles, phase transition type adsorption is a phenomenon that occurs with the strong attractive forces between the adsorbed particles, and adsorption limited type adsorption is a phenomenon that occurs with the repulsive forces between the adsorbed particles. The theoretical analysis-only using fundamental thermodynamics and occupancy statistics though-qualitatively quite well explains the experimental results.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.4
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• pp.76-83
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• 2003

To cope with stringent performance targets requested in many fields spanning the whole range of industry, the driver is necessary to realize large dynamic range as well as nano resolution, manipulate the mover orientation without additional driver, and be suitable for clean environment. As one of those purposes, authors have developed the planar precision stages with the integrated operating principle of levitation and propel. In this paper, we discuss potential of magnetic suspension technology by comparing various features of non-contact planar stages, that is, repulsive type of surface actuator and attractive type of surface actuator.

• Polymer(Korea)
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• v.35 no.6
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• pp.513-519
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• 2011

Molecular simulations via the molecular dynamics method have been carried out to investigate the dynamic collision properties of penetrable-sphere model fluids. The collision frequencies, the mean free paths, the angle distributions of the hard-type reflection and the soft-type penetration, and the effective packing fractions are computed over a wide range of the packing fraction ${\phi}$ and the repulsive energy ${\varepsilon}^*$. The soft-type collisions are dominated for lower repulsive energy systems, while the hardtype collisions for higher repulsive energy systems. Very interestingly, the ratio of the soft-type (or, the hard-type) collision frequency to the total collision frequency is directly related with the Boltzmann factor of acceptance (or rejection) probabilities in the canonical ensemble Monte Carlo calculations. Such dynamic collision properties are shown to be restricted for highly repulsive and dense systems of ${\varepsilon}^*{\geqq}3.0 $and ${\phi}{\geqq}0.7$, indicating the cluster forming structures in the penetrable-sphere model.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.291-297
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• 2018

Due to difficulty in minimally invasive surgery, training simulator is actively researched. A volumetric deformable organ is created by employing a shape-retaining chain-linked (S-chain) model to realize positioning a human organ model in virtual space. Since the main principle of the S-chain algorithm is that the repulsive force is proportional to the number of chain elements, the calculation time can be increased according to the magnitude of deformation. In this work, the advanced S-chain algorithm is used to calculate the repulsive torque according to spin motion. Finally, haptic architecture was constructed using this S-chain model by incorporating the virtual organ with a real master device, which allows the repulsive force and target position to be transferred to each other. The control performance of S-chain algorithm has been evaluated via experiment.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.12
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• pp.988-995
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• 2010

In this study the (Alnico, Sm-Co) bonded magnets were fabricated by mixing the Sm-Co added alnico alloy powders with epoxy resin and binder, appropriately. Also, the hybrid ring magnets of (Alnico, Sm-Co)/Sr-ferrite were fabricated by coupling the Sr-ferrite composite layer with an (Alnico, Sm-Co) magnet. The magnetic properties of (Alnico, Sm-Co) ring magnets were varied with the amount of Sm-Co powders. The addition of Sm-Co powders increased a remanent induction($B_r$) and coercive force($_BH_C$), while decreasing a surface flux density and repulsive distance. The surface flux density and repulsive distance for the (Alnico, Sm-Co) ring magnet increased with a magnetizing voltage up to about 160 V and reached an apparent saturation point. Also, the measurements of temperature and moisture characteristics showed that the surface flux densities of N-S poles and repulsive distance decreased a little within 4% after 10 days passed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.12
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• pp.1220-1226
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• 2012

This paper proposes a novel type of tactile device utilizing magnetorheological(MR) fluid which can be applicable for haptic master of minimally invasive surgery(MIS) robotic system. The salient feature of the controllability of rheological properties by the intensity of the magnetic field(or current) makes this potential candidate of the tactile device. As a first step, an appropriate size of the tactile device is designed and manufactured via magnetic analysis. Secondly, in order to determine proper input magnetic field the repulsive forces of the real body parts such as hand and neck are measured. Subsequently, the repulsive forces of the tactile device are measured by dividing 5 areas. The final step of this work is to obtain desired force in real implementation. Thus, in order to demonstrate this goal a neuro-fuzzy logic is applied to get the desired repulsive force and the error between the desired and actual force is evaluated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.415-420
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• 2012

This paper proposes a novel type of tactile device utilizing magnetorheological (MR) fluid which can be applicable for haptic master of minimally invasive surgery (MIS) robotic system. The salient feature of the controllability of rheological properties by the intensity of the magnetic field (or current) makes this potential candidate of the tactile device. As a first step, an appropriate size of the tactile device is designed and manufactured via magnetic analysis. Secondly, in order to determine proper input magnetic field the repulsive forces of the real body parts such as hand and neck are measured. Subsequently, the repulsive forces of the tactile device are measured by dividing 5 areas. The final step of this work is to obtain desired force in real implementation. Thus, in order to demonstrate this goal a neuro-fuzzy logic is applied to get the desired repulsive force and the error between the desired and actual force is evaluated.

• Journal of Surface Science and Engineering
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• v.39 no.2
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• pp.76-81
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• 2006

Molecular dynamics simulations were carried out to investigate physical sputtering of Fe(100) substrate due to energetic ion bombardments. Repulsive interatomic potentials at short internuclear distances were determined with ab initio calculations using the density functional theory. Bohr potentials were fitted to the ab initio results on diatomic pairs (Ar-Fe, Fe-Fe) and used as repulsive screened Coulombic potentials in sputtering simulations. The fitted-Bohr potentials improve the accuracy of the sputtering yields predicted by molecular dynamics for sputtering of Fe(100), whereas Moliere and ZBL potentials were found to be too repulsive and gave relatively high sputtering yields. In spite of assumptions and limitations in this simulation work, the sputtering yields predicted by the molecular dynamics method were in fairly good accordance with the obtainable experimental data in absolute values as well as in manner of the variation according to the Incident energy. Threshold energy for sputtering of Fe(100) substrate was found to be about 40 eV. Additionally, distributions of kinetic energies of sputtered atoms and their original depths could be obtained.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.5
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• pp.694-700
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• 2015

This paper deals with the design of 1-kW troidal type gyro. In general, gyro can be used as magnet bearing or flywheel energy storage device. The proposed troidal type gyro is used as a flywheel energy storage device. The gyro is capable of high-speed rotation in the air. The coriolis effect is taken into account when designing the rotor of the proposed gyro. Also the repulsive power of the permanent magnet is considered while selecting the shape and the thickness of the magnet. The neodymium is used as material of the magnets in this paper. The number of magnets are selected accordingly to reduce these torque ripples because torque ripples is an important factor while designing the gyro. The designed troidal type gyro is verified through the Finite Element Method (FEM).

• Asia pacific journal of information systems
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• v.34 no.2
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• pp.493-517
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• 2024

E-commerce has grown to be perceived as an integral component of modern customers' lives. Fast innovation enables businesses to implement new business ideas that enhance customers' shopping experiences. The motive is to study the allurement of unrestrained buying behaviors resulting from Live Streaming Commerce in the presence of Emotional imagery. The conceptual model and hypotheses for the study have been framed based on the SOR model. A survey was conducted in north India, where data was collected from 577 consumers experiencing live streaming and analyzed with the help of AMOS and SPSS software. The repulsive behavior scale has been developed by using qualitative research. The findings revealed that there is a significant relationship between the stimulus of livestreaming and unrestrained buying behaviors with the mediating role of emotional imagination. Two crucial mediating factors, pleasure, and arousal (fervent imagination), have successfully predicted experiential shopping behavior. The study has implications for online marketers and policymakers, as marketers can use our developed model to understand consumers' different buying behaviors, and policymakers can select and design specific features for the social presence of live streaming. Integrating three different types of unrestrained buying behavior influenced by live streaming would add to the literature. The study adds value to the literature by developing a scale to measure repulsive behavior after testing and validating with experts.