• 제목/요약/키워드: n-th moment

검색결과 23건 처리시간 0.024초

Simplified Machine Diagnosis Techniques by Impact Vibration using n-th Moment of Absolute Deterioration Factor

  • Takeyasu, Kazuhiro;Amemiya, Takashi;Tanaka, Jumpei;Masuda, Shiro
    • Industrial Engineering and Management Systems
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    • 제4권1호
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    • pp.68-74
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    • 2005
  • Among many dimensional and dimensionless amplitude parameters, kurtosis (4-th normalized moment of probability density function) is generally regarded as a sensitive good parameter for machine diagnosis. However, higher order moment may be supposed to be much more sensitive. Bicoherence is an absolute deterioration factor whose range is 1 to 0. The theoretical value of n-th moment divided by n-th moment calculated by measured data would behave in the same way. We propose a simplified calculation method for an absolute index of n-th moment and name this as simplified absolute index of n-th moment. Some favorable results are obtained.

A Lattice Distribution

  • Chung, Han-Young
    • Journal of the Korean Statistical Society
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    • 제10권
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    • pp.97-104
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    • 1981
  • It is shown that a lattice distribution defined on a set of n lattice points $L(n,\delta) = {\delta,\delta+1,...,\delta+n-1}$ is a distribution induced from the distribution of convolution of independently and identically distributed (i.i.d.) uniform [0,1] random variables. Also the m-th moment of the lattice distribution is obtained in a quite different approach from Park and Chung (1978). It is verified that the distribution of the sum of n i.i.d. uniform [0,1] random variables is completely determined by the lattice distribution on $L(n,\delta)$ and the uniform distribution on [0,1]. The factorial mement generating function, factorial moments, and moments are also obtained.

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Moments of a Class of Internally Truncated Normal Distributions

  • Kim, Hea-Jung
    • Communications for Statistical Applications and Methods
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    • 제14권3호
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    • pp.679-686
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    • 2007
  • Moment expressions are derived for the internally truncated normal distributions commonly applied to screening and constrained problems. They are obtained from using a recursive relation between the moments of the normal distribution whose distribution is truncated in its internal part. Closed form formulae for the moments can be presented up to $N^{th}$ order under the internally truncated case. Necessary theories and two applications are provided.

Efficient Computations for Evaluating Extended Stochastic Petri Nets using Algebraic Operations

  • Kim, Dong-Sung;Moon, Hong-Ju;Bahk, Je-Hyeong;Kwon, Wook-Hyun;Zygmunt J. Haas
    • International Journal of Control, Automation, and Systems
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    • 제1권4호
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    • pp.431-443
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    • 2003
  • This paper presents an efficient method to evaluate the performance of an extended stochastic Petri net by simple algebraic operations. The reachability graph is derived from an extended stochastic Petri net, and then converted to a timed stochastic state machine, using a semi-Markov process. The n-th moments of the performance index are derived by algebraic manipulations with each of the n-th moments of transition time and transition probability. For the derivation, three reduction rules are introduced on the transition trajectories in a well-formed regular expression. Efficient computation algorithms are provided to automate the suggested method. The presented method provides a proficient means to derive both the numerical and the symbolic solutions for the performance of an extended stochastic Petri net by simple algebraic manipulations.

Recurrence Formula for the Central Moments of Number of Successes with n Poisson Trials

  • Moon, Myung-Sang
    • Journal of the Korean Data and Information Science Society
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    • 제14권2호
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    • pp.385-391
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    • 2003
  • A sequence of n Bernoulli trials which violates the constant success probability assumption is termed as "Poisson trials". In this paper, the recurrence formula for the r-th central moment of number of successes with n Poisson trials is derived. Romanovsky's method, based on the differentiation of characteristic function, is used in the derivation of recurrence formula for the central moments of conventional binomial distribution. Romanovsky's method is applied to that of Poisson trials in this paper. Some central moment calculation results are given to compare the central moments of Poisson trials with those of conventional binomial distribution.

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A first-principles theoretical investigation of the structural, electronic and magnetic properties of cubic thorium carbonitrides ThCxN(1-x)

  • Siddique, Muhammad;Rahman, Amin Ur;Iqbal, Azmat;Azam, Sikander
    • Nuclear Engineering and Technology
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    • 제51권5호
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    • pp.1373-1380
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    • 2019
  • Besides promising implications as fertile nuclear materials, thorium carbonitrides are of great interest owing to their peculiar physical and chemical properties, such as high density, high melting point, good thermal conductivity. This paper reports first-principles simulation results on the structural, electronic and magnetic properties of cubic thorium carbonitrides $ThC_xN_{(1-x)}$ (X = 0.03125, 0.0625, 0.09375, 0.125, 0.15625) employing formalism of density-functional-theory. For the simulation of physical properties, we incorporated full-potential linearized augmented plane-wave (FPLAPW) method while the exchange-correlation potential terms in Kohn-Sham Equation (KSE) are treated within Generalized-Gradient-Approximation (GGA) in conjunction with Perdew-Bruke-Ernzerhof (PBE) correction. The structural parameters were calculated by fitting total energy into the Murnaghan's equation of state. The lattice constants, bulk moduli, total energy, electronic band structure and spin magnetic moments of the compounds show dependence on the C/N concentration ratio. The electronic and magnetic properties have revealed non-magnetic but metallic character of the compounds. The main contribution to density of states at the Fermi level stems from the comparable spectral intensity of Th (6d+5f) and (C+N) 2p states. In comparison with spin magnetic moments of ThSb and ThBi calculated earlier with LDA+U approach, we observed an enhancement in the spin magnetic moments after carbon-doping into ThN monopnictide.

CHARACTERIZATION OF SOME CONTINUOUS DISTRIBUTIONS BY PROPERTIES OF PARTIAL MOMENTS

  • Abraham, B.;Nair, N. Unnikrishnan;Sankaran, P.G.
    • Journal of the Korean Statistical Society
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    • 제36권3호
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    • pp.357-365
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    • 2007
  • In this paper we present characterizations of the Pareto, Lomax, exponential and beta models by some properties of their $r^{th}$ partial moment defined as ${\alpha}_r(t)=E[(X-t)^+]^r$, where $(X-t)^+ = max(X-t,0)$. Given the partial moments at a few truncation points, these results enable us to calculate the moments at many other points.

Synthesis and Characterization of Homo Binuclear Macrocyclic Complexes of UO2(VI), Th(IV), ZrO(IV) and VO(IV) with Schiff-Bases Derived from Ethylene diamine/Orthophenylene Diamine, Benzilmonohydrazone and Acetyl Acetone

  • Mohapatra, R.K.;Ghosh, S.;Naik, P.;Mishra, S.K.;Mahapatra, A.;Dash, D.C.
    • 대한화학회지
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    • 제56권1호
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    • pp.62-67
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    • 2012
  • A series of homo binuclear complexs of the type $[M_2(L/L^')(NO_3)n].mH_2O$, [where $M=U{O_2}^{2+},\;Th^{4+},\;ZrO^{2+}$] and $[(VO)_2(L/L^')(SO_4)_2]{\cdot}2H_2O$, L=1,5,6,9,12,15,16,20 octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (OTTDO) or L'=10:11;21:22-dibenzo-1,5,6,9,12,15,16,20-octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (DOTTOT), n=4 for $U{O_2}^{2+}$, $ZrO^{2+}$ n=8 for $Th^{4+}$ m=1,2,3 respectively, have been synthesized in template method from ethylenediamine/orthophenylene diamine, benzil monohydrazone and acetyl acetone and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR studies. The results indicate that the VO(IV) ion is penta co-ordinated yielding paramagnetic complexes; $UO_2(VI)$, ZrO(IV) ions are hexa co-ordinated where as Th(IV) ion is octa co-ordinated yielding diamagnetic complexes of above composition. The fungi toxicity of the ZrO(IV) and VO(IV) complexes against some fungal pathogen has been studied.

VCC를 첨가한 다중 전류형 인버터 구동에 관한 연구 (A Study on Drive of the Multicurrent Source Inverter Inserting the VCC)

  • 정연택;홍일선;황락훈
    • 대한전기학회논문지
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    • 제38권4호
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    • pp.269-278
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    • 1989
  • When the induction motor is operated by CSI, the commutation capacitance in the CSI circuit is increased according to the increase of large capacitor system. The output voltage spikes are generated at the moment of charge and discharge of the commutation capacitor. Also, since output current comprise a great number of harmonics, torque ripples of the motor are generated, having bad effects on the motor. In this study, by adopting the 18-phase multiple high Frequency Current Source Inverter (HFCSI), torque ripples generated by the voltage spikes are mostly eliminated except the 17th and 19th harmonics. To reduce the voltage spikes comprised in the output voltage, particularly, the methods of eliminating the cause of bad effect upon the motor are proposed in this paper. In the proposed method, by using additional voltage Clamping Curcuit (VCC), it is possible to select the values of commutation capacitor energy loss in commutating, the commutating capacitor, and the capacitor in the clamping circuit.

3-Benzylidine/Furfurylidine/(Pyridyl/Thienyl-2'-methylene) imino-5-p-sulphonamido phenyl azo-2-thiohydantoins와 UO2(VI), ZrO(IV) 및 Th(IV) 이온의 동종이핵 착물에 대한 합성 및 특성 (Synthesis and Characterization of Homobinuclear Complexes of UO2(VI), ZrO(IV) and Th(IV) ions with 3-Benzylidine/Furfurylidine/(Pyridyl/Thienyl-2'-methylene) imino-5-p-sulphonamido phenyl azo-2-thiohydantoins)

  • Dash, D.C.;Mahapatra, A.;Naik, P.;Mohapatra, R.K.;Naik, S.K.
    • 대한화학회지
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    • 제55권3호
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    • pp.412-417
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    • 2011
  • [$M_2L(NO_3)_n(H_2O)_m$]의 일반식을 갖는 일련의 동종이핵 착물을 합성하여 원소분석, 열분석, 몰 전기전도도, 자기모멘트 및 분광학적 방법(IR, UV-vis 및 $^1H$-NMR)을 통해 특성을 조사하였다. 이 경우, 일반식에 있어서 M=$UO_2$(VI), ZrO(IV), Th(IV); L=3-benzylidine-imino-5-p-sulphonamido phenyl azo-2-thiohyatoin(bispt), 3-furfurylidine-imino-5-psulphonamido phenyl azo-2-thiohydantoin(fispt),3-pyridyl-2'-methylene-imino-5-p-sulphonamido phenyl azo-2-thiohydantoin (pmispt) 및 3-thienyl-2'-methylene-imino-5-p-sulphoanamido phenyl azo-2-thiohydantoin(tmispt); Th(IV)에 대해서 n=8 그 외의 것에 대해서는 n=4, bispt에 대해서는 m=4 그 외의 것에 대해서는 m=3을 의미한다. 이러한 결과에서 얻은 정보를 통해 리간드들은 4배위를 하는 것으로 확인되었는데, 즉 한 중심금속은azomethine 질소 및 카르보닐 산소에 배위되는 반면, 또 다른 중심금속은 아조 질소 및 thioimido 질소에 배위되어 위의 조성을 갖는 동종이핵 착물을 이룬다. 몇 가지 병원균에 대한 리간드와 그들의 지르코닐 착물의 독성 연구도 수행하였다.