• 제목/요약/키워드: size series

검색결과 1,511건 처리시간 0.03초

Effect of Inclination Angle and Size of Heated Surface on Pool Boiling CHF

  • Yang, Soo-Hyung;Baek, Won-Pil;Chang, Soon-Heung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1999년도 춘계학술발표회요약집
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    • pp.155-155
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    • 1999
  • Pool boiling critical heat flux (CHF) have been investigated using plate type test sections with different widths (3 cm & 4 cm) and lengths (10 cm, IS cm & 20 cm) under various incli- nation angles. As the inclination angle increases from $0^{\circ}$ (horizontally facing downward plate) to $30^{\circ}$, CHF sharply increases. After that angle, CHF gradually increases with the increase of the inclination angle. There must be a transition angle between $0^{\circ}$ and $30^{\circ}$, at which the CHF increase rate remarkably changes. According to the comparison of present and previous ex- periments, the transition angle may be affected by heater size and increase with the increase of heater size. The size effect of heated surface on CHF is noticeable in the L15 & L20 series and W4 series; however, it seems to be difficult to find the size effect in L10 series and W3 series.

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Size Refinement of Empirical Likelihood Tests in Time Series Models using Sieve Bootstraps

  • Lee, Jin
    • Communications for Statistical Applications and Methods
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    • 제20권3호
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    • pp.199-205
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    • 2013
  • We employ sieve bootstraps for empirical likelihood tests in time series models because their null distributions are often vulnerable to the presence of serial dependence. We found a significant size refinement of the bootstrapped versions of a Lagrangian Multiplier type test statistic regardless of the bandwidth choice required by long-run variance estimations.

우리 나라 토양의 입도특성 (The Particle Size Distribution of Korean Soils)

  • 우철웅;장병욱
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.163-166
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    • 2003
  • In this study, a grouping of particle-size distributions(PSDs) by means of the fuzzy c-means clustering method(FCM) was presented. The classification was performed with the whole and the major soil series representing pedological origin. In case of the major soil series, PSDs were clustered as $2{\sim}4$ groups and the characteristics of clustering results were quite different between the soil series. It was found that the characteristics of PSDs at center of each class can be explained by formation process of each soil series. In case of whole soil data, PSDs were classified to 8 classes in which 4 classes were single mode and 4 classes were bimode distributions. Through this study, it is concluded that pedogenetic process is a plausible explanation for grain size distribution of soils.

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MISCLASSIFICATION IN SIZE-BIASED MODIFIED POWER SERIES DISTRIBUTION AND ITS APPLICATIONS

  • Hassan, Anwar;Ahmad, Peer Bilal
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제13권1호
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    • pp.55-72
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    • 2009
  • A misclassified size-biased modified power series distribution (MSBMPSD) where some of the observations corresponding to x = c + 1 are misclassified as x = c with probability $\alpha$, is defined. We obtain its recurrence relations among the raw moments, the central moments and the factorial moments. Discussion of the effect of the misclassification on the variance is considered. To illustrate the situation under consideration some of its particular cases like the size-biased generalized negative binomial (SBGNB), the size-biased generalized Poisson (SBGP) and sizebiased Borel distributions are included. Finally, an example is presented for the size-biased generalized Poisson distribution to illustrate the results.

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고강도·고인성 구상흑연주철의 피로한도의 개선 (Improvement of Fatigue Limit in Spheroidal Graphite Cast Iron with High Strength and Toughness)

  • 김민건;김진학
    • 열처리공학회지
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    • 제12권1호
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    • pp.40-46
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    • 1999
  • Rotary bending fatigue tests were carried out to investigate the improvement of fatigue limit in annealed and austempered spheroidal graphite cast iron. Main results obtained are as follows. (1) The tensile strength(hardness) of Series C is higher than that of Series B, and fatigue limits are 245MPa in Series C, 230MPa in Series B and 195MPa in Series A, respectively. (2) The fatigue limits of Series B and Series A are mainly governed by the resistance to fatigue crack initiation. Whereas, the fatigue limit of Series C is governed by the resistance to fatigue crack initiation and growth. The defect size and the resistance to crack initiation and growth should be considered to clarify the fatigue properties in spheroidal graphite cast iron. (3) Improvement of fatigue limit by half-austempering is more reasonable than that of full-austempering treatment in multi defective materials as spheroidal graphite cast iron.

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중국 의복사이즈의 규격설정에 관한 현황분석 (Analysis of Current Size Establishment of Clothing Sizes in China)

  • 심부자;권영자
    • 복식
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    • 제53권1호
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    • pp.117-128
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    • 2003
  • For the advance of Korea's ready-made clothes industry into China, we need some information about the body types of the Chinese and the sizes of ready-made clothes. The purpose of this study is to prepare basic data about the reality and process of the size establishment of clothing sizes in China. The conclusions are as follows. 1. Clothing size establishment was made three times in 1981, 1991, and 1997. At present, the version of 'GB/T 1335-1997 Size' is used. 2. 'GB/T 1335-1997 Size' is composed as follows. \circled1 Based on the drop values of chest girth and waist girth, 4 (Y. A, B, C) body types of adult men and women were chosen. \circled2 Sizes contains Ho and Hyoung, 'Ho' refer to height (cm) and serve as the standard of length, while 'Hyoung' indicate chest girth (cm) and act as the standard of girth. \circled3 The size divisions of the 3 basic items for adults are 5cm (height), 4cm (chest girth), and 2cm (waist girth). So they are named '5ㆍ4, 5ㆍ2 size series', \circled4 For grading in dress production, approximate values to the means of the 2 basic items are called 'center types'.\circled5 Other necessary items for clothing design besides 3 basic items are named 'control items'. \circled6 For babies, children, and adolescents, no body type classification is established. Instead, size series are established according to body height.

Determinacy on a Maximum Resolution in Wavelet Series

  • Park, Chun-Gun;Kim, Yeong-Hwa;Yang, Wan-Youn
    • Journal of the Korean Data and Information Science Society
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    • 제15권2호
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    • pp.467-476
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    • 2004
  • Recently, an approximation of a wavelet series has been developed in the analyses of an unknown function. Most of articles have been studied on thresholding and shrinkage methods for its wavelet coefficients based on (non)parametric and Bayesian methods when the sample size is considered as a maximum resolution in wavelet series. In this paper, regardless of the sample size, we are focusing only on the choice of a maximum resolution in wavelet series. We propose a Bayesian approach to the choice of a maximum resolution based on the linear combination of the wavelet basis functions.

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구상화율에 의한 구상 흑연주철재의 피로강도의 정량적 평가 (Quantitative Evaluation of Fatigue Strength by Spheroidal of Graphite in Ductile Cast Iron)

    • 한국생산제조학회지
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    • 제8권5호
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    • pp.36-41
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    • 1999
  • Although the problems of defects and nonmetallic inclusion in metal fatigue are very complicated it is particularly important to view these problems from the perspective that defects and inclusions are virtually equivalent to small cracks. This concept will help us to understand various fatigue phenomena caused by graphite of Ductile cast iron. Therefore in this study different ferrite-pearlite matrix structure and pheroidal ratio of graphite of 70%, 80% and 90% GCD40 , GCD45-2 series have been carried out rotary bending fatigue test estimated the maxi-mum size of graphite investigated correlation. It was concluded as follows : (1) in ductile cast iron which have various spheroidal ratio of graphite the fatigue limit C series of 90% spheroidal ratio of graphite is the highest. While A series of 70% spheroidal ratio of graphite is the lowest (2) fatigue limit was predicted by vickers hardness(Hv) of matrix {{{{ SQRT {area } }}}} of maximum size graphite inputting Murakami and Endo's formula.

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가변 샘플 크기의 이산 코사인 변환을 활용한 시계열 데이터 압축 기법 (Compression Methods for Time Series Data using Discrete Cosine Transform with Varying Sample Size)

  • 문병선;최명환
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제22권5호
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    • pp.201-208
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    • 2016
  • 실시간으로 여러 시계열 데이터를 수집, 저장하는 데는 많은 저장 공간을 요구하게 된다. 이러한 공간 문제를 해결하는 방안으로, 이산 코사인 변환 압축에서 가변 샘플 크기를 사용하는 방안을 제안하였다. 시계열 데이터 셋은 값의 변화가 작을수록, 그리고 변화의 빈도가 낮을수록 압축률이 높아지는 특성을 가지고 있으며 이러한 특성을 잘 반영할 수 있는 척도로 변동 계수와 인접 요소 간 변동성 계수를 사용하여 가변 샘플 크기를 결정하는 데 사용하였다. 여러 실제 데이터 셋을 대상으로 시험한 결과, 두 방식 모두 양호한 압축률을 보이고 있다. 그러나 인접 요소간 변동성 계수 기반 압축 방식이 변동 계수 기반 방식 보다 샘플 크기 결정 방식이 훨씬 간단할 뿐만 아니라 보다 나은 압축률을 보임을 확인하였다.

Biphenyl thioester 계열 강유전성액정의 합성 및 물성에 관한 연구 (Synthesis and mesomorphic properties of biphenly thioester series in ferroelectric liguke crystal)

  • 전영재
    • 한국재료학회지
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    • 제3권1호
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    • pp.72-83
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    • 1993
  • 비페닐 티오에스터 계열 강유전성 액정물질에 대한 새로운 합성방법이 논의되었다. 합성된 많은 액정물질들은 강유전성 스메틱 C상 뿐만 아니라 키랄네마틱과 스메틱 A상을 나타내었으며, $10^{-8}$C/c$m^2$ 이상의 큰 자발분극을 나타내었다. 이 계열들로써 우리는 비대칭 탄소에 붙은 치환체의 크기와 분극도가 자발분극에 미치는 영향을 조사하였으며 치환체의 크기에 대한 Sc*상의 안정도를 결정할 수 있었다.

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