• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.6
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• pp.223-232
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• 2001

Aiming at a small axial pump with a levitated rotor, an axial-type self-bearing motor is presented, which has a rotor wish four permanent magnets and two stators with two-pole three-phase windings. In this system, only the axial motion of rotor is actively controlled by two opposite self-bearing motors just like in the case of an axial magnetic bearing, while the other motions are passively stable. For rotation, It follows the theory of a four-pole three-phase synchronous motor. This paper Introduces schemes for design and control of the self-bearing motor and shows some experimental results to Prove the feasibility of application for the axial Pump.

• The Journal of Korean Institute of Information Technology
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• v.16 no.11
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• pp.61-68
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• 2018

This paper describes design of a 10.525 GHz self oscillating mixer semiconductor IC chip combining voltage controlled oscillator and frequency mixer using silicon CMOS technology for Doppler radar applications. The p-core type VCO included in the self oscillating mixer minimizes the noise contained in the transmitted signal. This noise minimization increases the sensing distance and acts in a direction favorable to the reaching distance and the sensitivity of the motion detection sensor. Simulation results for phase noise show that a VCO designed as a P-core has a noise characteristic of -106.008 dBc / Hz at 1 MHz offset and -140.735 dBc / Hz at 25 MHz offset compared to a VCO designed with N-core and NP-core showed excellent noise characteristics. If a self-oscillating mixer is implemented using a p-core designed VCO in this study, a motion sensor with excellent range and reach sensitivity will be produced.

• Science of Emotion and Sensibility
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• v.6 no.1
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• pp.11-16
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• 2003

In this study, we examined the evaluation of virtual Reality (VR) according to the use of motion platform. We recorded electrogastrogram, skin conductance, blood volume, skin temperature, heart rate, and the frequency of eyeblink before, during, after virtual navigation in 33 subjects. We used simulator sickness questionnaire, presence questionnaire , and self-report to evaluate cybersickness and presence in VR system. All subjects experienced VR two times in Motion platform condition and non-Motion platform condition at two-week intervals. Presence score of motion platform condition was greater than non-motion platform condition. The frequency and severity of cybersickness were significantly reduced in motion platform condition than non-motion platform condition. These results suggest that the use of motion platform that synchronizes visual presentation provides higher presence and reduces cybersickness.

• Journal of Korean society of Dental Hygiene
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• v.20 no.4
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• pp.525-533
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• 2020

Objectives: This study was conducted to facilitate improvements in career preparation behavior and career development of dental hygiene students by investigating the effects of self-leadership and career decision self-efficacy on the career preparation behavior of dental hygiene students. Methods: A self-reported questionnaire was filled out by 190 dental hygiene students between August 20 to October 31, 2019. The data were analyzed using SPSS 20.0. Independent t-test, one way ANOVA, the Scheffe posthoc test, and the Pearson correlation results were reviewed, and a multiple regression analysis was conducted. Results: Self-leadership, career decision self-efficacy, and career preparation behavior were scored 3.29, 3.36, and 2.91 points, respectively. The variables that influenced career preparation behavior were the motion of major select and self-leadership. These factors had 30.5% of variance among dental hygiene students. Conclusions: Institutional support, including counseling and leadership education by professors and students, is needed in schools to improve the career preparation behavior of students majoring in dental hygiene.

• Wind and Structures
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• v.27 no.5
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• pp.293-309
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• 2018

The prediction of multimode flutter relies, to a larger extent than bimodal flutter, on accurate modeling of the self-excited forces since it is challenging to perform experimental validation by using aeroelastic tests for a multimode case. This paper sheds some light on the accuracy of predicted self-excited forces by comparing numerical predictions of self-excited forces with measured forces from wind tunnel tests considering the flutter vibration mode. The critical velocity and the corresponding flutter vibration mode of the Hardanger Bridge are first determined using the classical multimode approach. Then, a section model of the bridge is forced to undergo a motion corresponding to the flutter vibration mode at selected points along the bridge, during which the forces that act upon it are measured. The measured self-excited forces are compared with numerical predictions to assess the uncertainty involved in the modeling. The self-excited lift and pitching moment are captured in an excellent manner by the aerodynamic derivatives. The self-excited drag force is, on the other hand, not well represented since second-order effects dominate. However, the self-excited drag force is very small for the cross-section considered, making its influence on the critical velocity marginal. The self-excited drag force can, however, be of higher importance for other cross-sections.

• Journal of Korean Academy of Nursing
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• v.23 no.2
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• pp.255-268
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• 1993

This descriptive correlational research was conducted to compare the relationship between self-esteem performance of antenatal care and health pro-motion lifestyles for unmarried and married pregnant women. The sample consisted of 94 married women attending one general hospital and residing in Seoul and 82 unmarried women from two social institutes for unmarried women. The tool used for this study was a structured questionnaire which was developed and revised by the researcher. The tool consisted of 12 items related to demographic characteristics, 10 items on self-esteem measurement, 20 items on performance of antenatal care and 37 items on health promotion lifestyle profile. The data collected from the interviews were analyzing using the SPSS, yielding frequencies, percentiles, means, standard deviations, t-test, ANOVA, Pearson’s Product Moment Correlation. The results of this study are as follows : 1) The demographic variables for the two groups were heterogenous except for religion. 2) The results of the comparison between the two groups were significantly different for self-esteem, married women(mean 20.41, standard deviation 3. 94) had higher scores on self-esteem than unmarried women(mean 24.02, standard deviation 4.11), (t=-5.91, p .001) 3) There was a stastically significant difference between the two groups on the health promotion lifestyle profile. The married women had higher scores on the health promotion lifestyle profile (t=7.22, p〈.001) 4) The score for married women on performance of antenatal care has higher than the score for unmarried women(t=8.83, p〈.001) 5) With regard to the relationship between health promotion lifestyle and performance of antenatal care and self-esteem, the correlation coefficient between self-esteem and health Promotion lifestyle for married women was .45, between per formance of antenatal care and health promotion lifestyle, .54, between self-esteem and performance of antenatal care, .32. For the unmarried women, between self-esteem and health promotion lifestyle, .39, between performance of antenatal care and health promotion lifestyle, .67, between self-esteem and performance of antenatal care, .30. 6) There was a statistically significant different between the two groups on all subconcepts of the health promotion lifestyle profile (p〈.001). 7) Comparison of the order of the scores between the two groups for the married women showed that the highest score was for nutrition, then self-actualization, interpersonal support, health responsibility, stress management and exercise in that order. For the unmarried women the highest score was for self-actualization followed by nutrition, interpersonal support, stress management, health responsibility, and exercise in that order. The score in the exercise domain was lowest in both groups. In conclusion, on the basis of the results of this study, resources and protection facilities for unmarried pregnant women could be improved through government policies and health care policies that would allow unmarried women to utilize significant social support resources and actualize health pro-motion lifestyles. Nursing should offer interventions to increase psychosocial adjustment and support tp improve the quality of life for unmarried pregnant women and further to promote improved growth and development of the infants.

• Journal of Korean Society of Transportation
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• v.32 no.5
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• pp.503-512
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• 2014

In this paper, various tire blow-out force experiment data were collected and analyzed to obtain approximate values of related coefficients such as rolling resistance, self-aligning torque, cornering stiffness, and radial stiffness for the analysis of the motion of vehicles with tire blow-outs. These coefficients related to tire blow-outs were input into a vehicle accident analysis program to simulate and examine the effects of tire blow-outs. Various configurations and velocities of vehicle collisions without tire blow-outs were also used as reference to establish collision events of vehicle collisions with tire blow-outs. For the events, the simulation analysis was performed and collision characteristics were obtained. Consideration of tire blow-outs or damages suggested in this study will greatly contribute to more reliable vehicle accident reconstructions.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.2
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• pp.411-420
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• 2013

We consider fractional Gussian noise and FARIMA sequence with Gaussian innovations and show that the suitably scaled distributions of the FARIMA sequences converge to fractional Gaussian noise in the sense of finite dimensional distributions. Finally, we figure out ACF function and estimate the self-similarity parameter H of FARIMA(0, $d$, 0) by using R/S method.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.50-53
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• 1988

This paper presents an approach to the position control of a robot manipulator by using a self-tuning pole-placement controller with an inverse model. The linearized independent difference equations of manipulator motion are obtained, and the parameters of these models are estimated on line. The controller is composed of two parts, the primary controller obtains desired torques by using an inverse model and the secondary controller computes variational torques on the basis of induced perturbation equations by minimizing a quadratic criterion with a closed-loop pole-placement. Simulation is performed to demonstrate the effectiveness of this approach.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.89-89
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• 2012

Arrangement of individual atoms and molecules with atomic precision and understanding the resulting properties at the molecular level are ultimate goals of chemistry, biology, and materials science. For the past three decades, scanning probe microscopy has made strides towards these goals through the direct observation of individual atoms and molecules, enabling the discovery of new and unexpected phenomena. This talk will discuss the origin of forces governing motion of small organic molecules and their extended self-assembly into two-dimensional surface structures by direct observation of individual molecules using scanning tunneling microscopy (STM).