• Title/Summary/Keyword: Scaling)

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Manual Scaling of Ionograms Measured at Jeju (33.4°N, 126.3°E) Throughout 2012

  • Jeong, Se-Heon;Kim, Yong Ha;Kim, Ki-nam
    • Journal of Astronomy and Space Sciences
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    • v.35 no.3
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    • pp.143-149
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    • 2018
  • The ionosphere has been monitored by ionosondes for over five decades since the 1960s in Korea. An ionosonde typically produces an ionogram that displays radio echoes in the frequency-range plane. The trace of echoes in the plane can be read either manually or automatically to derive useful ionospheric parameters such as foF2 (peak frequency of the F2 layer) and hmF2 (peak height of the F2 layer). Monitoring of the ionosphere should be routinely performed in a given time cadence, and thus, automatic scaling of an ionogram is generally executed to obtain ionospheric parameters. However, an auto-scaling program can generate undesirable results that significantly misrepresent the ionosphere. In order to verify the degree of misrepresentation by an auto-scaling program, we performed manual scaling of all 35,136 ionograms measured at Jeju ($33.43^{\circ}N$, $126.30^{\circ}E$) throughout 2012. We compared our manually scaled parameters (foF2 and hmF2) with auto-scaled parameters that were obtained via the ARTIST5002 program. We classified five cases in terms of the erroneous scaling performed by the program. The results of the comparison indicate that the average differences with respect to foF2 and hmF2 between the two methods approximately correspond to 0.03 MHz and 4.1 km, respectively with corresponding standard deviations of 0.12 MHz and 9.58 km. Overall, 36 % of the auto-scaled results differ from the manually scaled results by the first decimal number. Therefore, future studies should be aware of the quality of auto-scaled parameters obtained via ARTIST5002. Hence, the results of the study recommend the use of manually scaled parameters (if available) for any serious applications.

Development of measurement scale for Korean scaling fear-1.1 (한국형 스케일링두려움 측정도구 개발(KSF-1.1))

  • Cho, Myung-Sook;Yi, Seung-Ju
    • Journal of Korean society of Dental Hygiene
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    • v.12 no.4
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    • pp.675-684
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    • 2012
  • Objectives : The purpose of this study was to develop an instrument for Korean Scaling Fear (KSF)-1.1 in scaling patients. Methods : 402 sample size for scaling patients was studied in Daegu city in July and August of 2011. Mean and standard deviation was calculated in 3 dimensions(FWS: fear while scaling, DDH: distrust on dental hygienist, FAS: fear after scaling). Results : Age of 402 subjects was 36.5 years. In analyzing reliability for item-level, a range of correlation coefficient(${\alpha}$) on item-internal consistency(FWS, DDH, and FAS) was 0.58~0.88(${\alpha}$=0.90), 0.40~0.71(${\alpha}$=0.82), and 0.54~0.63(${\alpha}$=0.82), respectively. Floor(%) and ceiling(%) value on 3 dimensions were also 9.2% and 4.0%, 12.4% and 0.5%, and 17.7% and 1.2%, respectively, therefore, we found statistically high reliability for those(p<0.001). With explanatory factor analysis, this study could generate 3 dimensions(factor 1, eigenvalue 5.41, proportion 0.49; factor 2, eigenvalue 1.50, proportion 0.14; factor 3, eigenvalue 1.04, proportion 0.09) and 11 sub-scales. Also confirmatory factor analysis results showed that the KSF1.1 model was fitted very well in analysis of model fit($x^2$=112.94, df=41, p=0.000; goodness of fit index=0.95; adjusted goodness of fit index=0.92; root mean square residual=0.057). Conclusions : In conclusion, The findings of this study showed that developed reliable and valid instrument for measuring the KSF1.1 in the scaling patients.

Gingival color change after scaling & subgingival root planing (치석제거술과 치은연하 치근면활택술 후 치은의 색조 변화)

  • Kim, Young-Seok;Lim, Sung-Bin;Chung, Chin-Hyung
    • Journal of Periodontal and Implant Science
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    • v.31 no.3
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    • pp.501-511
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    • 2001
  • Several indices have been developed that use bleeding and color changes as indicators of early gingival pathology. In the presence of gingivitis, vascular proliferation and reduction of keratinization owing to increase redness in gingiva. Descriptions of healthy gingiva are numerous, ranging from pale pink and coral pink to deep red and violet. This terms are not objective. Because of perception of color depends on a lot of factors such as light source, object, observer and so on. It is difficult to make an objective expression. Therefore the using of mechanical equipment is recommended to exclude these variables and observer's vias. The purpose of this study was to evaluate gingival color change after scaling & subgingival root planing. The other purpose of this study was to research the correlation of pocket depth, P.B.I. score and gingival color change. After photo-taking and storaging the image of gingival color into a computer, color change was examine with an image analysis program. Results were as follow; 1. Color of healed gingiva after scaling & subgingival root planing was significantly differ from color of inflamed gingiva(p<0.01). 2. Color of healed gingiva after scaling was similar to color of healed gingiva after subgingival root planing(p<0.05). 3. There was statistically significant correlation between color change of red component and pocket depth after scaling & subgingival root planing(p<0.01). 4. There was no correlation between color change of green, blue component and pocket depth after scaling & subgingival root planing(p<0.01). 5. There was statistically significant correlation between between color change of red component and P.B.I. score after scaling & subgingival root planing(p<0.01). 6. There was no correlation between color changes of green, blue component and P.B.I. score after scaling & subgingival root planing(p<0.01). 7. Increase of pocket depth and P.B.I. score were significantly correlated to the amount of color change(p<0.01). 8. P.B.I. score had a higher correlation with color change than pocket depth(p<0.01).

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Influence of Mechanical Properties and Pore Structure on the Scaling Resistance of Concretes (콘크리트의 역학적 성능 및 공극구조가 스케일링 저항성에 미치는 영향)

  • Lee, Seung-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.111-118
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    • 2016
  • The scaling of concrete caused by the combined effects of frost and deicing salt is one of the principle causes of damage to transportation infrastructure in cold-climate regions. In this study, to evaluate the factors affecting scaling resistance of concrete, the relationship between the properties of concrete, such as the mechanical properties and pore structure, and scaling resistance was examined experimentally. The test results showed that the scaling resistance was strongly dependent on the absorption properties of concrete, but not on the compressive strength. Furthermore, it is believed that both the spacing factor and specific surface of the air voids was not a good parameter for evaluating the scaling resistance of concrete. SGC concrete was less durable than OPC and SFC concrete with respect to the scaling resistance in the scope of the present study.

Adaptive Scaling Based on Vision in Micromanipulation

  • Lee, Jaehoon;Park, Jong-Oh;Yoon, Pil-Sang;Lee, Seok-Joo;Park, Jong-Hyeon;Kim, Kyunghwan
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.116.6-116
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    • 2002
  • $\textbullet$ Concept of Adaptive Scaling Factor $\textbullet$ Initial Value and Boundary Conditions $\textbullet$ Adaptive Scaling Factor $\textbullet$ Simulation and Experimental Results

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A Study on the Impedance Scaled Tele-Nanomanipulation in a Nanoscale Virtual Environment (나노 스케일 가상환경에서의 나노-원격 조작의 임피던스 스케일링에 관한 연구)

  • Kim, Sung-Gaun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.11 s.254
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    • pp.1401-1407
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    • 2006
  • In a haptic interface system with a nanoscale virtual environment (NVE) using an atomic force microscope (AFM), impedance scaling is important. In order to explicitly derive the relationship between performance and impedance scaling factors, a nanoscale virtual coupling (NSVC) concept and a selection method of scaling factors of velocity (or position) and force are introduced. An available scaling factor region is represented based on Llewellyn's absolute stability criteria and the physical limitation of the haptic device. Experiments have been performed for tele-nanomanipulation tasks such as positioning, indenting and nanolithography with available force scaling factor in the NVE.

SUNSPOT MODELING AND SCALING LAWS

  • SKUMANICH A.
    • Journal of The Korean Astronomical Society
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    • v.36 no.spc1
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    • pp.1-5
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    • 2003
  • In an early paper Skumanich suggested the existence of a scaling law relating the mean sunspot magnetic field with the square-root of the photospheric pressure. This was derived from an analysis of a variety of theoretical spot models including those by Yun (1968). These were based on the Schliiter-Temesvary (S- T) similarity assumption. To answer criticisms that such modeling may have unphysical (non-axial maxima) solutions, the S-T model was revisited, Moon et al. (1998), with an improved vector potential function. We consider here the consequences of this work for the scaling relation. We show that by dimensionalizing the lateral force balance equation for the S- T model one finds that a single parameter enters as a characteristic value of the solution. This parameter yields Skumanich's scaling directly. Using an observed universal flux-radius relation for dark solar magnetic features (spots and pores) for comparison, we find good to fair agreement with Yun's characteristic value, however the Moon et al. values deviate significantly.

The effects of depression and anxiety on pain in ultrasonic scaling treatment (초음파스케일링 시 환자의 우울, 불안이 통증에 미치는 영향)

  • Hwang, Mi;Kim, Sook-Hyang;Lee, Kyeong-Hee
    • Journal of Korean society of Dental Hygiene
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    • v.14 no.3
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    • pp.439-446
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    • 2014
  • Objectives : The purpose of the study is to investigate the correlation between the pain, depression, dental anxiety in the patients visiting to dental clinic for the ultrasonic scaling treatment. Methods : The study is a cross-sectional correlation study. A self-reported questionnaire was filled out by 254 patients having no history of mental illness in Seoul and Gyeonggido from December 12 to 20, 2013. The study instruments included modified Beck's Depression Inventory (BDI), STAI items by Spilberger, Humphis' Modified Dental Anxiety Survey(MDAS), and Visual Analogue Scale. Results : There existed correlation between the ultrasonic scaling pain, depression, dental anxiety, trait anxiety, and state anxiety. Dental anxiety was the most influencing factors on the pain. Conclusions : It is very important to reduce the anxiety in the patients more actively.

Control of Electromagnetic Levitation System using ε-scaling Partial State Feedback Controller (ε조절 요소를 가진 부분 상태 궤환 제어기를 이용한 자기부상 시스템의 제어)

  • Park, Gyu-Man;Choi, Ho-Lim
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.8
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    • pp.1572-1576
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    • 2011
  • The electromagnetic levitation(EMS) system is one of the well-known nonlinear system because of its nonlinearity and several control techniques have been proposed. We propose an ${\epsilon}$-scaling partial feedback controller for the ball position control of the EMS system. The key feature of our proposed controller is the use of the scaling factor ${\epsilon}$ which provides a function of controller gain tuning along with robustness. In this paper, we show the stability analysis of our proposed controller and the convergence analysis of the state observer in terms of ${\epsilon}$-scaling factor. In addition, the experimental results show the validity of the proposed controller and improved control performance over the conventional PID controller.