• 대한수학회보
• /
• 제47권3호
• /
• pp.585-592
• /
• 2010

Let {$\varepsilon_i:-{\infty}$$\infty$} be a strictly stationary sequence of linearly positive quadrant dependent random variables and $\sum\limits\frac_{i=-{\infty}}^{\infty}|a_i|$<$\infty$. In this paper, we prove the precise asymptotics in the law of iterated logarithm for the moment convergence of moving-average process of the form $X_k=\sum\limits\frac_{i=-{\infty}}^{\infty}a_{i+k}{\varepsilon}_i,k{\geq}1$

• The Journal of the Acoustical Society of Korea
• /
• 제18권4E호
• /
• pp.20-25
• /
• 1999

To get accurate natural frequencies of an engine crankshafts, finite element equations of motion are developed, taking real geometries of the shaft into account. For the crankshaft with wide crank webs, a specialized rotating web element is developed. This includes the effects of rotary inertia, gyroscopic moment, and shear. After the finite element equations are constructed, eigenvalues are extracted from the system equations to get natural frequencies, based on the Sturm sequence method which exploits the banded forms of the system matrices to reduce computations. The scheme developed can be used for the free vibration analysis of any type of spinning structures which include skew symmetric gyroscopic moment matrix in the system matrices. The results are compared with experimental data in order to confirm the study.

• 산업기술연구
• /
• 제18권
• /
• pp.97-105
• /
• 1998

The most of the design engineers for construction has academic background of bachelors degree. Theories for advanced composite structures are too difficult for such engineers and some simple but accurate enough methods are necessary. The senior author has reported that some laminate orientations have decreasing values of $D_{16}$, $B_{16}$, $D_{26}$ and $B_{26}$ stiffnesses as the ply number increases. Such plates behave as special orthotropic plates and simple formulas developed by the author can be used. Most of the bridge and building slabs on girders have large aspect ratios. For such cases further simplification is possible by neglecting the effect of the longitudinal moment terms($M_x$) on the relevant partial differential equations of equilibrium. In this paper, the result of the study on the subject problem is presented.

• 대한치과교정학회지
• /
• 제30권4호
• /
• pp.467-473
• /
• 2000

각형 호선이 edgewise 브라켓에 삽입되면 first, second order는 bending에 의해, third order는 torsion(비틀림)에 의해 3차원적인 force system이 발생한다. Bending에 관하여는 분석적 그리고 실험적인 많은 연구가 보고 되어 있는 반면 비틀림에 관해서는 상대적으로 많은 연구가 이루어 지지 않았다. 본 연구의 목적은 각형 와이어의 재료와 단면의 형태가 와이어의 비틀림 모멘트에 어떻게 영향을 주는지를 이론적, 실험적으로 밝혀서 임상적으로 적절한 모멘트를 가할 때 호선의 재료와 굵기를 합리적으로 선택할 수 있도록 하는데 있다. 실험재료로는 third order조절을 위해 가장 많이 사용하는 호선을 사용하였다. 크기별로 0.016x0.022, 0.017x0.025, 0.019x0.025인치 그리고 재료로는 stainless steel (Ormco), TMA(Ormco), NiTi(Ormco), 그리고 braided stainless steel(DentaFlex, Dentauum) 네 가지를 사용하여 총 12개의 조합을 사용하였다. Torsion formula를 이용하여 비틀림 강성 (torque/twist rate)을 계산하였고 torque gauge를 이용하여 비틀림 강성, 항복 비틀림 모멘트 (yield torsional moment), 그리고 최대 비틀림 모멘트 (ultimate torsional moment)를 측정하였다. Torsion formula에 의하면 비틀림 강성 (T/$\theta$)은 재료적인 특성(G)과 호선의 단면의 특성(J)에 비례하고 호선의 길이(L)에 반비례한다. 대부분의 실험치는 이론적인 값과 비슷하게 나타났다.

• 호남수학학술지
• /
• 제16권1호
• /
• pp.111-117
• /
• 1994

In this note we prove a functional central. limit theorem for LPQD sequences, statisfying some moment conditions. No stationarity is required. Our results imply an extension of Birkel's functional central limit theorem for associated processt'S to an LPQD sequence and an improvement of Birkel's functional central limit theorem for LPQD sequences.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
• /
• pp.424-429
• /
• 1998

Numerical studies are performed to investigate the behavior of flat plates under combined in-plane and out-of-plane loads. The numerical model is verified by comparison with experiments for plates simply supported on four edges. Through study on different load combination and loading sequence, the critical load condition that governs the strength of the flat plate is determined. Parametric studies are performed to investigate the buckling coefficient and the effective flexural rigidity so that the moment magnification method is applicable to the flat plates.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 1990년도 PROCEEDINGS OF THE FIRST KOREA-JAPAN JOINT GEOTECHNICAL SEMINAR ON EXCAVATION and TUNNELING IN URBAN AREAS
• /
• pp.111-128
• /
• 1990

Three numerical analysis carried out for the design of a diaphragm wall were examined by the results of field observation data. Utilizing the wall stiffness, supporting system and construction sequence, the relative merits of those factors on the analysis of diaphragm wall have been investigated and their effects are compared tilth the observed behaviour of the wall. The predicted bending moment and wall displacement by elasto-plastic method agreed well with the observed values. The rigid slab supported system (i.e Top-Down Method) found to be the most effective way of controlling ground movement.

• 대한수학회지
• /
• 제49권2호
• /
• pp.235-249
• /
• 2012

In the paper by Liu and Lin (Statist. Probab. Lett. 76 (2006), no. 16, 1787-1799), a new kind of precise asymptotics in the law of large numbers for the sequence of i.i.d. random variables, which includes complete convergence as a special case, was studied. This paper is devoted to the study of this new kind of precise asymptotics in the law of large numbers for moving average process under $\phi$-mixing assumption and some results of Liu and Lin [6] are extended to such moving average process.

• Communications for Statistical Applications and Methods
• /
• 제7권1호
• /
• pp.291-296
• /
• 2000

Petrov(1996) examined the connection between general moment conditions and the applicability of the strong law lf large numbers to a sequence of pairwise independnt and identically distributed random variables. In this note wee generalize Theorem 1 of Petrov(1996) and also show that still holds under assumption of pairwise negative quadrant dependence(NQD).

• 대한수학회논문집
• /
• 제18권4호
• /
• pp.725-736
• /
• 2003

Let $A_1,{\;}A_2,...,A_n$ be a sequence of events on a given probability space. Let $m_n$ be the number of those $A'_{j}s$ which occur. Upper bounds of P($m_n{\;}\geq{\;}1) are obtained by means of probability of consecutive terms which reduce the number of terms in binomial moments $S_2,n,S_3,n$ and $S_4,n$.