• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.757-762
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• 2002

This study focused on the investigation of durability of latex modified concrete in the points of surface scaling resistance as cement types variated and latex content variated such as 5%, 10%, 15%, and 20%. An increasing the amount of latex produced concrete with increased flexural strength, but with slightly lower compressive strength. The increase in flexural strength might be attributed to the latex films between the hydrated cement and aggregates, and the decrease in compressive strength to the flexibility of the latex component named by Butadiene. The surface scaling resistance test was used to evaluate the durability of latex-modified concretes and rapid setting latex-modified concretes. The surface scaling resistance of LMC was quite good comparing to conventional concrete. Further, surface scaling resistance of RSLMC was improved with increasing the latex content.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.347-352
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• 2016

This paper investigates the application, design and implementation of unscented Kalman filter observer using the various scaling parameters for the sensorless speed control of a permanent magnet synchronous motor. The principles of unscented transformation and unscented Kalman filter are examined and their applications are explained. Typically the mapping transformation process is divided into two types, namely the basic unscented transformation and the general unscented transformation by virtue of the scaling parameter value. And resultantly, the number of sampling points, weights, code configuration and computation time are different. But there is no little information on the scaling parameter value or how this value influences the system performance. To analyze the unscented transformation with the various scaling parameters in this study, the experimental results under a wide range of operation condition have been demonstrated.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.416-418
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• 2006

In this paper, a new acoustic echo cancellation approach based on the DUET algorithm and scaling factor estimation is proposed to solve the scaling ambiguity in case of blind separation based acoustic echo cancellation in a noisy environment. In hands-free full-duplex communication system. acoustic noises picked up by the microphone are mixed with echo signal. For this reason, the echo cancellation system may provide poor performance. For that purpose, a degenerate unmixing estimation technique, adjusted in the time-frequency domain, is employed to separate undesired echo signals and noises. Also, since scaling and permutation ambiguities have not been solved in the blind source separation algorithm, kurtosis for the desired signal selection and a scaling factor estimation algorithm are utilized in this rarer for the separation of an echo signal. Simulation results demonstrate that the proposed approach yields better echo cancellation and noise reduction performances, compared with conventional methods.

• Publications of The Korean Astronomical Society
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• v.7 no.1
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• pp.51-61
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• 1992

The nonlinear stochastic behavior of chaotic inflation is characterized by the 'scaling' effect. Using a simple criterion for the appearance of scaling behavior in the ${\lambda}{\phi}^4$ inflation model, we show explicitly that in this limit the onset of the scaling regime does not require any special initial conditions and that it is independent of the self-coupling constant ${\lambda}$. Non-Gaussian statistics in adiabatic fluctuations are important only for super-horizon scales and the scaling regime does not lead to any significant statistical properties on currently observable scales. However, the scaling effect gives some cosmological consequences very different from what we expect in the naive diffusion approximation for quantum fluctuations. The classical (deterministic) treatment of the inflation field (essentially a quantum mechanical object.) becomes valid towards the end of inflation.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2237-2242
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• 2011

Anomalous scaling behaviors such as significantly large growth exponent (${\beta}$) and small reciprocal of dynamic exponent (1/z) values for many molecular crystalline thin films have been reported. In this study, the variation of scaling exponent values and consequent growth behaviors of molecular thin films were more quantitatively analysed using a (1+1)-dimensional surface lateral diffusion model. From these simulations, influence of step edge barriers and grain boundaries of molecular thin films on the various scaling exponent values were elucidated. The simulation results for the scaling exponents were also well consistent with the experimental data for previously reported molecular thin film systems.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.833-838
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• 1995

This study presents a method to predict plant-specific and operational history dependent scaling factors. Realistic and detailed approaches are taken to find scaling factors at reactor coolant. This approach begins with fission product release mechanisms and fundamental release properties of fuel-source nuclide such as fission product and transuranic nuclide. Scaling factors at various waste streams are derived from the predicted reactor coolant scaling factors with the use of radionuclide retention and build up model. This model makes use of radioactive material balance within the radioactive waste processing systems. According to input parameters of plant operation history, scaling factors predicted at reactor coolant and waste streams are well brought out the effects of plant operation history.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.387-397
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• 2017

The purpose of this study is to investigate the regional change of dental scaling experience by scaling insurance coverage in July, 2013. The data were used in the "Community Health Survey" of the 2012 and 2014. The results of the study are as follows; 1) The subjective oral health status and brushing of lunch was highest in Gangnam-gu in both 2012 and 2014(p<0.001). 2) Regular dental check-up was high in Gangnam-gu in both 2012 and 2014(p<0.001). 3) The Scaling experience rate increased in all three regions(p<0.001). 4) The socio-demographic characteristics and scaling experience were higher in 2012 and 2014(p<0.001). The scaling experience was higher when there were office workers and spouses(p<0.001). From the policy perspective, it seems necessary to take measures to reduce the gap in scaling experience rate due to differences in income and unequal medical environment.

• Journal of Korean society of Dental Hygiene
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• v.15 no.1
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• pp.31-38
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• 2015

Objectives: The purpose of this study is to investigate the factors of oral health beliefs on scaling performance by national health insurance coverage in consumers. Methods: The subjects were 353 people living in Seoul, Incheon, and Gyeonggi-do from September 25 to October 20, 2013. They filled out the self-reported questionnaire after receiving informed consents. The questionnaire included 6 questions of general characteristics, 6 questions of oral health behavior, 6 questions of health insurance coverage, and 1 question of subjective oral health recognition. The oral health belief consisted of 6 questions of seriousness, 6 questions of susceptibility, 8 questions of barriers, 5 questions of benefit, and 3 questions of self-efficacy measure by Likert 5 scale. Cronbach's alpha in the study was 0.759. Data were analyzed using SPSS version 20.0 for frequency analysis, t-test, ANOVA, post-hoc Scheffe test, Pearson's correlation coefficient, and binary logistic regression. Results: The influencing factors of oral health belief model were Seriousness(${\beta}=0.091$), Self efficacy(${\beta}=-0.471$) and age(${\beta}=0.855$)(p<0.05). Those who had highly perceived seriousness and younger age tended to have probability of scaling performance. Higher self-efficacy tended to take more chance to have scaling performance probability. Conclusions: In order to cover the scaling by national health insurance, it is very important to notice the benefit of health insurance coverage of scaling to the consumers. National health insurance coverage enables the scaling practice to be easily accessible to the people. Easy access to scaling by low cost strategy can improve the oral health behavior.

• Journal of Korean Dental Hygiene Science
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• v.3 no.2
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• pp.39-49
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• 2020

The purpose of this study was to provide the basic data needed to plan the effective teaching design of scaling education and to measure the changes in students' confidence in performing scaling according to the number of scaling practices. Scaling education is presented as a core basic hygiene competency of dental hygienists and evaluated as the practical competency of dental hygienists. This study selected 48 third-year students from the department of dental hygiene at S University in Asan, and analyzed data from completed participant surveys. The degree of "confidence in facing the subject in clinical practice," "confidence in applying hand instrument to the subject," and "confidence in applying ultrasonic instruments to the subject" was assessed on a five-point Likert scale. The difference in confidence was analyzed during five practice sessions. Each response was compared using frequency analysis, chi-square test, and repeated measurement ANOVA. Students who complained of a lack of confidence in the 14.6%, 25.0%, and 12.5%, respectively, in face-to-face practice, hand instruments, and ultrasonic instrument application responses. The more the practice was repeated, the more confident students were in all three categories, and the more statistically significant (p<0.001). As the number of scaling practice sessions increased, students' confidence in performing scaling also improved. In particular, the level of self-confidence was higher after the third practice session when compared to the first session. Therefore, it is necessary to design effective courses for teaching scaling practices so that at least three repetitive practice periods can be provided in clinical dental hygiene practices.

• Journal of dental hygiene science
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• v.23 no.2
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• pp.176-184
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• 2023

Background: Recently, a piezoelectric ultrasonic scaler based on a feedback control mechanism was introduced for pain relief. This study aimed to investigate the effects of a new ultrasonic scaler in reducing pain and discomfort in adults. Methods: A newly introduced ultrasonic scaler (Master 700^®) was used as the test device and a conventional ultrasonic scaler device (PIEZON^®) was used as the control device. Forty-one healthy adults visited the dental clinic for dental scaling but did not undergo scaling or periodontal treatment within 6 months. Intraoral examinations were performed before scaling and 3 months later; before scaling, both devices were randomly assigned on the left or right side of each dentition (split-mouth model) and scaling was performed by a registered dental hygienist. The levels of pain and discomfort during scaling were evaluated subjectively and objectively using the visual analog scale (VAS) and physiological monitoring of the heart rate (HR), respectively. Time was measured for each device. Results: All clinical indicators, except bleeding on probing, significantly improved with both devices. The treatment times were 7 minutes, 13 minutes (control) and 6 minutes, 59 minutes (test). VAS scores for pain were 4.89±2.12 (control) and 4.58±2.77 (test) points out of 10; for noise, these were 4.68±2.33 (control) and 4.55±2.55 (test), and for vibration, the values were 4.26±2.0 (control) and 4.18±2.48 (test). HR averages were 72.34±3.39 (control) and 75.97±9.78 (test) beats/min. No statistically significant differences were observed between the devices. Conclusion:The pain, discomfort levels, and scaling time of the new piezoelectric ultrasonic scaler did not differ from those of the conventional device. Further research and development are necessary for more prominent pain-relief effects of scaling devices.