• 제목/요약/키워드: F distribution

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Pedestrian Distribution in High-Rise Commercial Complexes: An Analysis of Integrating Spatial and Functional Factors

  • Xu, Leiqing;Xia, Zhengwei
    • 국제초고층학회논문집
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    • 제5권2호
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    • pp.95-103
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    • 2016
  • One of the key problems in the design of high-rise commercial complex is how to guide reasonable pedestrian distribution in commercial space. In this study, pedestrian distribution in three high-rise commercial complexes in Shanghai and Hong Kong was studied using spatial configuration analysis software Space Syntax and quantification of physical elements in commercial spaces, such as functional attractiveness, entrances, escalators, level variations and passage width. Additionally, in an attempt to integrate functions with spatial integration and spatial depth, two combination variables, the spatial coefficient of function (IF) and spatial depth coefficient of function (F/D), were proposed. The results of the correlation analysis and multiple regression analyses reflected the following: (1) Regarding the influence on pedestrian distribution, there was a synergistic and complementary relationship between function and space; (2) The comprehensive flow distribution analytic model could successfully interpret flow distribution in high-rise commercial complexes and its R Square ranged up to about 70% in the three cases; (3) The spatial coefficient of function (IF) and spatial depth coefficient (F/D) could effectively integrate functions and spatial configuration, which could help close the gap between over-emphasis on function in commercial research and the lack of consideration of function in space-syntax analysis.

전산유체해석과 다구찌 및 미니탭 방법을 활용한 하수처리장 분배조 웨어 최적화 (Optimization of Distribution Basin Weirs at a Sewage Treatment Plant Based on Computational Fluid Analysis Using the Taguchi and Minitab Method)

  • 정용준;박해식;조영만
    • 한국환경과학회지
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    • 제30권12호
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    • pp.983-991
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    • 2021
  • The role of the distribution basin role is to apportion incoming raw water to the primary sedimentation basin as part of the water treatment process. The purpose of this study was to calculate the amount of water in the distribution basin using computational fluid dynamics (CFD) analysis and to find a way to improve any non-uniformity. We used the Taguchi method and the minitab tool as optimization methods. The results of the CFD calculation showed that the distribution flow had a deviation of 5% at the minimum inflow, 10% at the average inflow, and 22% at the maximum inflow. At maximum flow, the appropriate heights of the 7 weirs(C, D, A, B, E, F, G) were 40 mm, 20 mm, 20 mm, 0, 0, 0, and 20 mm, respectively, according to the Taguchi optimization tool. Here, the maximum deviation of the distribution amount was 9% and the standard deviation was 23.7. The appropriate heights of the 7 weirs, according to the Minitab tool, were 40 mm, 20 mm, 20 mm, 0, 0, 0, and 20 mm, respectively, for weirs C, D, A, B, E, F, and G. Therefore, the maximum deviation of the distribution amount was 8% and the standard deviation was 17.1, which was slightly improved compared to the Taguchi method.

F-O-O-F 인젝터의 혼합 특성 (The mixing characteristics of Unlike Split Triplet(F-O-O-F) Impinging-Jet Injector Elements)

  • 임병직;정기훈;윤영빈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.283-286
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    • 2002
  • The mixing of fuel and oxidizer and each mass distribution of unlike split triplet(F-O-O-F) injector for liquid rocket which are known to affect the combustion efficiency significantly, has been investigated using PLLIF technique. Experiment is conducted to investigate the effect of mixture ratio(MiR), momentum ratio(MoR) and impinging angle on mixing efficiency. The mixing efficiency, which is introduced by Rupe, gives the global chracteristic of spray mixing. Experiment far comparison with triplet injector(F-O-F), which has same momentum ratio and impinging angle with split triplet injector is conducted.

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ANGULAR DISTRIBUTION OF SOLUTIONS OF HIGHER ORDER LINEAR DIFFERENTIAL EQUATIONS

  • Wu, Zhaojun;Sun, Daochun
    • 대한수학회지
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    • 제44권6호
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    • pp.1329-1338
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    • 2007
  • In this paper, we study the location of zeros and Borel direction for the solutions of linear homogeneous differential equations $$f^{(n)}+A_{n-1}(z)f^{(n-1)}+{\cdots}+A_1(z)f#+A_0(z)f=0$$ with entire coefficients. Results are obtained concerning the rays near which the exponent of convergence of zeros of the solutions attains its Borel direction. This paper extends previous results due to S. J. Wu and other authors.

RADIAL OSCILLATION OF LINEAR DIFFERENTIAL EQUATION

  • Wu, Zhaojun
    • 대한수학회보
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    • 제49권5호
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    • pp.911-921
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    • 2012
  • In this paper, the radial oscillation of the solutions of higher order homogeneous linear differential equation $$f^{(k)}+A_{n-2}(z)f^{(k-2)}+{\cdots}+A_1(z)f^{\prime}+A_0(z)f=0$$ with transcendental entire function coefficients is studied. Results are obtained to extend some results in [Z. Wu and D. Sun, Angular distribution of solutions of higher order linear differential equations, J. Korean Math. Soc. 44 (2007), no. 6, 1329-1338].

Strong Representations for LAD Estimators in AR(1) Models

  • Kang, Hee-Jeong;Shin, Key-Il
    • Journal of the Korean Statistical Society
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    • 제27권3호
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    • pp.349-358
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    • 1998
  • Consider the AR(1) model $X_{t}$=$\beta$ $X_{t-1}$+$\varepsilon$$_{t}$ where $\beta$ < 1 is an unknown parameter to be estimated and {$\varepsilon$$_{t}$} denotes the independent and identically distributed error terms with unknown common distribution function F. In this paper, a strong representation for the least absolute deviation (LAD) estimate of $\beta$ in AR(1) models is obtained under some mild conditions on F. on F.F.

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방사성 동위원소 (99mTc, 18F) 선원 사용 시 인체 내부피폭의 정량적 평가를 위한 선량분포 연구 (Dose Distribution Study for Quantitative Evaluation when using Radioisotope (99mTc, 18F) Sources)

  • 지영식;이동연;양현경
    • 한국방사선학회논문지
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    • 제16권5호
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    • pp.603-609
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    • 2022
  • 본 연구에서는 핵의학 분야에서 사용 빈도가 높은 방사성 동위원소 99mTc, 18F을 대상으로 물 팬텀과 전리함을 이용한 실측 데이터와 몬테카를로 법 기반의 모의실험 계산을 통해 인체 내 선량 분포를 평가하여 분석하였다. 실험 결과, 방사성 동위원소를 중심으로 거리가 멀어질수록 선량이 지수함수적으로 감소하는 것으로 나타났으며, 특히, 5 cm 이격 시 급격히 감소하는 경향을 보였다. 이를 수치상으로 보면, 99mTc의 경우 0.16 ~ 2.16 pC/min, 18F의 경우 0.49 ~ 9.29 pC/min 범위에서 형성되었다. 또한, 결과값을 이용하여 계산한 에너지 전달계수는 0.240 ~ 0.260 범위에서 실측값과 시뮬레이션 결과값이 유사하게 나타났다. 이와 같은 결과는 실험 결과값에 대한 신뢰도를 확보한 것으로 판단이 되며, 특히, 인체 내 선원 집적 시 선원 이동 경로를 중심으로 4 cm 이내에 위치한 장기에 선량이 많이 전달될 수 있다는 것을 의미한다. 본 연구는 방사성 동위원소에 의한 내부피폭 선량을 정량적으로 평가하기 위해 선원에서 발생하는 방사선 분포를 계산 하였으며, 실측과 모의실험 결과를 비교 분석을 통해 신뢰도가 높은 결과값을 제시할 수 있었다. 무엇보다도 계측기를 통해 체내 방사선 분포를 직접 측정하여 제시한 부분에서 큰 의미를 가지고 있다.

Can Functional Assessment Tools Reflect Balance Abilities at 3 Months after Total hip Arthroplasty?

  • Kim, Min-Woo;Ryu, Young-Uk
    • 대한물리의학회지
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    • 제13권4호
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    • pp.51-58
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    • 2018
  • PURPOSE: This study was conducted to determine if the Harrison hip score (HHS), a tool for assessing hip joint function, and the Burg balance scale (BBS), a general balance assessment tool, actually reflect the balance ability of total hip arthroplasty (THA) patients 3 months after surgery. In addition, this study investigated the initial weight distribution strategy for bilateral lower extremity after THA surgery to understand the balance of THA patients. METHODS: Fourteen 3-month THA patients performed static dual standing and sit-to-stand (STS) tasks. Ground reaction forces on each leg were collected to calculate the weight distribution symmetricity (SWD), and the HHS, functional HHS (f-HHS), and BBS were evaluated. Correlation analyses between SWD and the HHS (also f-HHS) and BBS were then applied to the THA patients. RESULTS: The correlations between functional evaluation tools (HHS, f-HHS, BBS) and SWD were weak strength for the static balance task, but moderate for the dynamic STS task. Among the evaluation tools used in the present study, f-HHS was most useful for evaluation of dynamic balance ability. CONCLUSION: The results suggest that use of HHS, f-HHS, and BBS as functional evaluation tools does not provide meaningful information regarding balance ability, but that they are useful for evaluating dynamic balance ability of THA patients. The dynamic balance ability at 3 months after THA seems to be under development.

A SKEWED GENERALIZED t DISTRIBUTION

  • NADARAJAH SARALEES
    • Journal of the Korean Statistical Society
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    • 제34권4호
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    • pp.311-329
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    • 2005
  • Skewed t distributions have attracted significant attention in the last few years. In this paper, a generalization - referred to as the skewed generalized t distribution - with the pdf f(x) = 2g(x)G(${\lambda}x$) is introduced, where g(${\cdot}$) and G (${\cdot}$) are taken, respectively, to be the pdf and the cdf of the generalized t distribution due to McDonald and Newey (1984, 1988). Several particular cases of this distribution are identified and various representations for its moments derived. An application is provided to rainfall data from Orlando, Florida.

On a Structure De ned by a Tensor Field F of Type (1, 1) Satisfying $ \prod\limits_{j=1}^{k}$[F2+a(j)F+λ2(j)I]=0

  • Das, Lovejoy;Nivas, Ram;Singh, Abhishek
    • Kyungpook Mathematical Journal
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    • 제50권4호
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    • pp.455-463
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    • 2010
  • The differentiable manifold with f - structure were studied by many authors, for example: K. Yano [7], Ishihara [8], Das [4] among others but thus far we do not know the geometry of manifolds which are endowed with special polynomial $F_{a(j){\times}(j)$-structure satisfying $$\prod\limits_{j=1}^{k}\;[F^2+a(j)F+\lambda^2(j)I]\;=\;0$$ However, special quadratic structure manifold have been defined and studied by Sinha and Sharma [8]. The purpose of this paper is to study the geometry of differentiable manifolds equipped with such structures and define special polynomial structures for all values of j = 1, 2,$\ldots$,$K\;\in\;N$, and obtain integrability conditions of the distributions $\pi_m^j$ and ${\pi\limits^{\sim}}_m^j$.