• 제목/요약/키워드: Scaling Relation

검색결과 137건 처리시간 0.021초

SUNSPOT MODELING AND SCALING LAWS

  • SKUMANICH A.
    • 천문학회지
    • /
    • 제36권spc1호
    • /
    • pp.1-5
    • /
    • 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.

DGMOSFET의 문턱전압과 스켈링 이론의 관계 (Relation of Threshold Voltage and Scaling Theory for Double Gate MOSFET)

  • 정학기
    • 한국정보통신학회논문지
    • /
    • 제16권5호
    • /
    • pp.982-988
    • /
    • 2012
  • 본 연구에서는 이중게이트(Double Gate; DG) MOSFET에서 문턱전압과 스켈링 이론의 관계를 관찰하였다. 기존 MOSFET의 경우 채널크기에 스켈링 이론을 적용하여 전류 및 스위칭주파수를 해석하였다. 이에 본 연구에서는 이중게이트 MOSFET에서 문턱전압의 경우 스켈링 이론의 적용가능성을 관찰하기 위하여 문턱전압의 변화를 스켈링 인자에 따라 관찰하고 분석하였다. 이를 위하여 이미 검증된 포아송방정식의 해석학적 전위분포를 이용하였으며 이때 가우스함수의 전하분포를 사용하였다. 분석결과 문턱전압이 스켈링 인자에 따라 크게 변화하였으며 변화정도는 도핑농도의 스켈링에 따라 변화한다는 것을 관찰하였다. 특히 이중게이트의 특성상 채널두께 및 채널길이에 스켈링 이론을 적용할 때 가중치를 이용한 변형된 스켈링 이론을 적용함으로써 이중게이트 MOSFET에 가장 타당한 스켈링 이론에 대하여 설명할 것이다.

퍼지 제어기의 Scaling Factor의 영향 분석 (Analysis of the Effects of Scaling Factors of Fuzzy Controller)

  • 이철희;서선학
    • 산업기술연구
    • /
    • 제15권
    • /
    • pp.195-202
    • /
    • 1995
  • In this paper, we analyze the effects of scaling factors on the performance of a fuzzy controller. The quantitative relation between input and output variables of a fuzzy controller is obtained by using a quasi-linear fuzzy model. And an approximate transfer function of a fuzzy controller is derived from the comparison of fuzzy controller with the conventional PID controller. Then we analyze the effects of scaling factor using this approximate transfer function and root locus method.

  • PDF

Comparing distances obtained from galaxy scaling-relations with the help of group catalogues

  • 크리스토프 사울다
    • 천문학회보
    • /
    • 제44권2호
    • /
    • pp.72.4-72.4
    • /
    • 2019
  • Galaxy scaling relations, such as the Tully-Fisher relation and the fundamental plane can be used to derive redshift-independent distances. These two scaling-relations are valid for mutually exclusive morphological galaxy types, solid group catalogues are required to compare them within galaxy clusters hosting multiple galaxies. With our investigation, we aim to better understand systematic effects between the scaling rations that may cause potential biases in peculiar motion studies.

  • PDF

치면세마 실습 대상자의 스케일링 경험에 영향을 미치는 요인분석 (Analysis of factors affecting the scaling experience of patients visiting the dental prophylaxis practice lab)

  • 윤현경;최규일
    • 한국치위생학회지
    • /
    • 제13권6호
    • /
    • pp.961-967
    • /
    • 2013
  • Objectives : The purpose of this study is to establish the regular scaling checkup service and to improve oral health care on the basis of knowledge, attitude, and belief by Dental Prophylaxis Practice Lab in A university. Methods : Subjects were 324 patients who visited Dental Prophylaxis Practice Lab in A university for the preventive removal of tartar from April to June 8, 2012. Data were analyzed using SPSS version 18.0 through the frequency analysis, chi-test, and logistics regression analysis. Results : In relation to scaling experience by age, 65.3% had experienced scaling checkup and those between 20 to 29 (34.7%) did not receive the scaling therapy. Smokers tended to have received more scaling experience than nonsmokers. Second, the number of untreated dental caries and missing teeth due to dental caries were important because the variables of oral health condition affected the scaling experience. Conclusions : It is necessary to increase the scaling experience and regular dental checkup by providing the education to improve dental clinics visit based on the knowledge and belief towards the scaling.

On the two different sequences of the mass-size relation for early-type galaxies

  • Kim, Jin-Ah;Yoon, Suk-Jin
    • 천문학회보
    • /
    • 제40권2호
    • /
    • pp.48.3-49
    • /
    • 2015
  • Scaling relations of early-type galaxies (ETG) provide a deep insight into their formation and evolution. Interestingly enough, most relations extending into the dwarf regimes display non-linear or broken-linear features, unlike the linear relations for normal (i.e., intermediate-mass to giant) ETGs only. Here we investigate the mass-size scaling relation of ETGs using a massive database of galaxies from SDSS DR12. We divide ETGs into two groups by the indication of star formation such as colors, and examine their distinction along the mass-size relation. We find that the mass-size distribution of blue, young normal galaxies is in good agreement with that of dwarf ETGs. Our result suggests that blue, young normal ETGs may serve as links between (passive) normal ETGs and dwarfs. We discuss the possibility of blue, young ETGs being progenitors of dwarf ETGs.

  • PDF

CAN MASSIVE GRAVITY EXPLAIN THE MASS DISCREPANCY-ACCELERATION RELATION OF DISK GALAXIES?

  • Trippe, Sascha
    • 천문학회지
    • /
    • 제46권3호
    • /
    • pp.133-140
    • /
    • 2013
  • The empirical mass discrepancy-acceleration (MDA) relation of disk galaxies provides a key test for models of galactic dynamics. In terms of modified laws of gravity and/or inertia, the MDA relation quantifies the transition from Newtonian to modified dynamics at low centripetal accelerations $a_c{\lesssim}10^{-10}ms^{-2}$. As yet, neither dynamical models based on dark matter nor proposed modifications of the laws of gravity/inertia have predicted the functional form of the MDA relation. In this work, I revisit the MDA data and compare them to four different theoretical scaling laws. Three of these scaling laws are entirely empirical; the fourth one - the "simple ${\mu}$" function of Modified Newtonian Dynamics - derives from a toy model of gravity based on massive gravitons (the "graviton picture"). All theoretical MDA relations comprise one free parameter of the dimension of an acceleration, Milgrom's constant aM. I find that the "simple ${\mu}$" function provides a good fit to the data free of notable systematic residuals and provides the best fit among the four scaling laws tested. The best-fit value of Milgrom's constant is $a_M=(1.06{\pm}0.05){\times}10^{-10}ms^{-2}$. Given the successful prediction of the functional form of the MDA relation, plus an overall agreement with the observed kinematics of stellar systems spanning eight orders of magnitude in size and 14 orders of magnitude in mass, I conclude that the "graviton picture" is sufficient (albeit probably not a necessary nor unique approach) to describe galactic dynamics on all scales well beyond the scale of the solar system. This suggests that, at least on galactic scales, gravity behaves as if it was mediated by massive particles.

일부 직장인의 구강건강상식 및 스케일링에 대한 인식도 (Affecting factors to oral scaling experience of the part worker)

  • 천석연;원복연
    • 한국치위생학회지
    • /
    • 제11권1호
    • /
    • pp.1-12
    • /
    • 2011
  • Objectives : This study was to investigate into company workers' oral scaling related factors and enhance a rate of oral scaling. Methods : From August 2010, self-administered questionnaires of the about general question items, oral health relation factors, knowledge of periodontal disease for oral scaling performed, in 267 people worker objects. Results : The followings are the findingd of this research. First, Oral scaling experiences were responded by 205 people(76.8%). Among those prevention the case which enforces with a goal periodically 6 month period 7.3% and the period of 1 years is 28.8%, be most inconvenient is cold(50.7%), with motive is dentistry visits inducement for tooth therapy which 51.2%, Non experience in oral scaling was responded by 62 people(23.2%), 45.2% of whom answered they had no necessity for such treatment. Second, Knowledge of periodontal disease is 'dental calculus and stain loses toothbrush quality did eagerly' incorrect one right answer ratio is highest with 86.5%, 'Becoming the adult being made to draw out tooth is periodontitis than decay' was incorrect one right answer rate was lowest with 62.9%. Third, The workers' sex, service field, one month average income, Currently the oral inconvenient presence, oral health Interest degree, tooth brushing method, knowledge of periodontitis have a significant effect on their oral scaling experience. Conclusions : When seeing with result of above, it is necessary of the oral scaling widely with the method which is various includes a mass communication by causing the changes in the perception of oral scaling. The dental hygienist is inconvenience from oral scaling experience have interest when is possible the patient comfortably, in order could be operated, endeavors demanded.

Analysis and Auto-tuning of Scale Factors of Fuzzy Logic Controller

  • Lee, Chul-Heui;Seo, Seon Hak
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
    • /
    • pp.51-56
    • /
    • 1998
  • In this paper, we analyze the effects of scaling factors on the performance of a fuzzy logic controller(FLC). The quantitative relation between input and output variables of FLC is obtained by using a qualsi-linear fuzzy model, and an approximate transfer function of FLC is dervied from the comparison of it with the conventional PID controller. Then we analyze in detail the effects of scaling factor using this approximate transfer function and root locus method. Also we suggest an on-line tuning method for scaling factors which employs an sample performance function and a variable reference for tuning index.

  • PDF

The Design of Fuzzy Controller Based on Genetic Optimization and Neurofuzzy Networks

  • Oh, Sung-Kwun;Roh, Seok-Beom
    • Journal of Electrical Engineering and Technology
    • /
    • 제5권4호
    • /
    • pp.653-665
    • /
    • 2010
  • In this study, we introduce a neurofuzzy approach to the design of fuzzy controllers. The development process exploits key technologies of Computational Intelligence (CI), namely, genetic algorithms (GA) and neurofuzzy networks. The crux of the design methodology deals with the selection and determination of optimal values of the scaling factors of fuzzy controllers, which are essential to the entire optimization process. First, the tuning of the scaling factors of the fuzzy controller is carried out. Next, we form a nonlinear mapping for the scaling factors, which are realized by GA-based neurofuzzy networks by using a fuzzy set or fuzzy relation. The proposed approach is applied to control nonlinear systems like the inverted pendulum. Results of comprehensive numerical studies are presented through a detailed comparative analysis.