• 제목/요약/키워드: Scaling)

검색결과 3,450건 처리시간 0.023초

라텍스개질 콘크리트 종류에 따른 표면 박리 저항 특성 (Surface Scaling Resistance of Latex-Modified Concretes)

  • 이훈재;김성환;홍창우;윤경구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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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.

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Sensorless Speed Control of Permanent Magnet Synchronous Motor by Unscented Kalman Filter using Various Scaling Parameters

  • Moon, Cheol;Kwon, Young Ahn
    • Journal of Electrical Engineering and Technology
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    • 제11권2호
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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.

잡음 상황에서 DUET 블라인드 신호 분리 알고리즘과 스케일 계수 추정을 이용한 음향 반향신호 제거 (Acoustic Echo Cancellation using the DUET Algorithm and Scaling Factor Estimation)

  • 김경재;서재범;남상원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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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.

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STOCHASTIC SCALING EFFECT AND STATISTICS OF COSMOLOGICAL DENSITY FLUCTUATIONS

  • Yi, In-Su;Vsihniac, Ethan T.
    • 천문학논총
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    • 제7권1호
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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.

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Study on Anomalous Scaling Exponents for Molecular Thin Film Growth Using Surface Lateral Diffusion Model

  • Gong, Hye-Jin;Yim, Sang-Gyu
    • Bulletin of the Korean Chemical Society
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    • 제32권7호
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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.

Development of a Scaling Factor Prediction Method for Radioactive Composition in Low-level Radioactive Waste

  • Park, Jin-Beak;Lee, Kun-Jai
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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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.

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스케일링 보험적용에 따른 일부지역의 스케일링 경험 변화 연구 (A Study on the Change of Dental Scaling Experience in Some Areas after Applying Scaling Insurance)

  • 박일순
    • 디지털융복합연구
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    • 제15권10호
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    • pp.387-397
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    • 2017
  • 본 연구는 2013년 7월 시행된 스케일링 보험화가 스케일링 경험에 영향을 미쳤는지를 알아보기 위한 것으로 '지역사회건강조사' 2012년과 2014년의 대도시 1개 구와 지방중소도시 2개 시지역의 자료가 분석에 이용되었다. 연구결과는 다음과 같다. 1) 주관적 구강건강수준과 점심식사 후 칫솔질은 2012년, 2014년 모두 강남구 지역이 가장 높았다.(p<0.001). 2) 구강검진 경험은 또한 2012년 2014년 모두 강남구 지역이 가장 많았다(p<0.001). 3) 스케일링 경험은 2012년 강남구 51.9%, 동해시 19.3%, 속초시 22.9%, 2014년 강남구 58.8%, 동해시 22.0%, 속초시 29.9%로 스케일링 경험이 다소 증가하였다(p<0.001). 4) 인구사회학적 특성과 스케일링 경험은 2012년 2014년 모두 학력과 소득이 높을수록(p<0.001), 사무직(p<0.001)과 배우자가 있을 때(p<0.001) 스케일링 경험이 높았다. 소득이나 불평등한 의료자원으로 인한 스케일링 경험률의 격차를 줄이기 위한 대책이 필요하다.

치과의료소비자의 구강건강신념이 건강보험 급여화에 따른 스케일링 행위에 영향을 미치는 요인 (The factors of oral health beliefs on scaling performance by national health insurance coverage in consumers)

  • 이명선;임희정
    • 한국치위생학회지
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    • 제15권1호
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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.

A Study on the Change of Clinical Self-Confidence according to the Number of Clinical Dental Hygiene Practices of Students in the Department of Dental Hygiene - Focusing on scaling practices -

  • 최용금;김미선;정수라;김은정
    • 대한치위생과학회지
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    • 제3권2호
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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.

Evaluation of Pain Reduction and Clinical Efficacy of Feedback-Controlled Ultrasonic Scaler

  • Min-ju Kim;Hee-jung Lim;Myoung-hee Kim;Young-sun Hwang;Im-hee Jung
    • 치위생과학회지
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    • 제23권2호
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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.