• 제목/요약/키워드: complex order

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프레임 차량의 주행 진동 저감을 위한 프레임 부시 복소동강성계수 크기 결정에 관한 연구 (A Study on Determination of Complex Stiffness of Frame Bush for Ride-comfort Improvement of Body-on-frame Vehicle)

  • 정면규;김기선;김광준
    • 한국소음진동공학회논문집
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    • 제16권6호
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    • pp.619-626
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    • 2006
  • Body-on-frame type vehicle has a set of frame bushes between body and frame for vibration isolation. Such frame bushes are important vibration transmission paths to passenger space for excitations during driving. In order to reduce the vibration level of passenger space, therefore, change of complex stiffness of the frame bushes is more efficient than modification of other parts of the vehicle such as body, frame and suspension. The purpose of this study is to reduce the vibration level for ride comfort by optimization of complex stiffness of frame bushes. In order to do this, a simple finite element vehicle model was constructed and complex stiffness of the frame bushes was set to be design variables. The objective function was defined to reflect frequency dependence of passenger ride comfort. Genetic algorithm and sub-structure synthesis were applied for minimization of the objective function. After optimization level at a position of interest on the car body was reduced by about 43.7 % in RMS value. Causes for optimization results are discussed.

A comparative study of early leaf development in the Viola albida complex

  • CHOI, Yong Kuk;WHANG, Sung Soo
    • 식물분류학회지
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    • 제49권1호
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    • pp.1-7
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    • 2019
  • Early leaves within the Viola albida complex were investigated by scanning electron microscopy in order to determine the morphological segments during morphogenesis. The early leaf development of V. albida var. albida could be morphologically divided into the eight stages in the following order: I, the initiation of shoot germination; II, the conical growth directionally of the leaf; III, the adaxial and abaxial formation of the leaf; IV, the initiation of the stipule; V, the formation of a transitional zone between the leaf blade and petiole; VI, the expansion of the upper part of the leaf blade; VII, the formation of almost all parts of the early leaf; VIII, the early simple leaf. Viola albida var. takahashii differs from V. albida var. albida by additional stages, i.e., V-1, the initiation of the first lateral lobe at the both lateral parts of the leaf after the stage V and an early lobed leaf. Viola albida var. chaerophylloides is also distinguished from two taxa by two developmental features, V-2, the initiation of a second lateral lobe below of the first lateral lobe, and an early palmately compound leaf. These findings suggest that the Viola albida complex would be in the process of peramorphosis, showing developmental changes in a chain of events, leading to a different leaf shape. These data would also be useful for isolating genes that give rise to different leaf morphogenesis outcomes among the taxa in the Viola albida complex.

공연문화공간의 복합기능 -예르바 부에나 센터와 토가무라 공연문화공간의 사례연구- (A Study on The Multi-Function of The Complex Cultural Center)

  • 김선영
    • 한국실내디자인학회논문집
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    • 제25호
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    • pp.84-93
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    • 2000
  • This study examines multiple functions of the complex cultural center. Recently, the importance of the complex cultural center has been growing, as peoples desire for cultural activities diversified. In order to effectively accommodate the general publics interests in various cultural activities, the complex cultural center tended to be multi-functional. At the same time, I argue that it is necessary to reexamine its functions in terms of how the multi-complex cultural center fits into local environment. Only when both peoples demand and local environment are fully integrated into its design, can the multi-complex cultural center accomplish the goal of multiple functions in a true sense.

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A SPECTRALLY ARBITRARY COMPLEX SIGN PATTERN

  • Liu, Sujuan;Lei, Yingjie;Gao, Yubin
    • Journal of applied mathematics & informatics
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    • 제28권1_2호
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    • pp.209-216
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    • 2010
  • A spectrally arbitrary complex sign pattern A is a complex sign pattern of order n such that for every monic nth degree polynomial f(x) with coefficients from $\mathbb{C}$, there is a matrix in the qualitative class of A having the characteristic polynomial f(x). In this paper, we show a necessary condition for a spectrally arbitrary complex sign pattern and introduce a minimal spectrally arbitrary complex sign pattern $A_n$ all of whose superpatterns are also spectrally arbitrary for $n\;{\geq}\;2$. Furthermore, we study the minimum number of nonzero parts in a spectrally arbitrary complex sign pattern.

The Short Time Spectra Analysis System Using The Complex LMS Algorithm and It's Applications

  • Umemoto, Toshitaka;Fujisawa, Shoichiro;Yoshida, Takeo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.58-63
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    • 1998
  • B.Widrow established fundamental relations between the least-mean-square (LMS) algorithm and the digital Fourier transform[1]. By extending these relations, we proposed the short time spectra analysis system using the LMS algorithm[2]. In that paper, we used the normal LMS algorithm on the thought of dealing with only real analytical signal. This algorithm minimizes the real mean-square by recursively altering the complex weight vector at each sampling instant. But, the short time spectra analysis sometimes deals with the complex signal that is outputted from complex analog filter. So, in order to optimize and develop this methods, furthermore it is necessary to derive an algorithm for the complex analytical signal. In this paper, we first discuss the new adaptive system for the spectra analysis using the complex LMS algorithm and then derive convergence condition, time constant of coefficient adjustment and frequency resolution by extending the discussion. Finally, the effectiveness of the proposed method is experimentally demonstrated by applying it to the measurement of transfer performance on complex analog filter.

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溫山工團 周邊의 森林植生에 관한 調査 (Study on forest vegetation in the vicinity of onsan industrial complex)

  • Kim, Jong-Gab
    • The Korean Journal of Ecology
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    • 제15권3호
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    • pp.231-246
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    • 1992
  • In order to estimate effects of air pollution for pinus thunbergii forests arounding onsan industrial complex, structure of forest vegrtation was surveyed. In the survey of forest vegetation, pinus densiflora have been died or being withered, and importance value(I.V) of rhododendron mucromulatum and lespedeza spp. were low at the vicinity of industrial complex. Especially lespedeza maximowiczii and l. maritima were not entirely appeared at the vicinity of industrial complex. I.V. of quercus serrata, robinia pseudoacacia and alnus firma were preferably high at the vicinity of industrial complex, and those of smilax china, rubus crataegifolius and rhus trichocarpa were similar at every site and it could be guessed that those had a tolerance. Number of species had a difference over 10 species at the vicinity of industrial complex as compared with those of remote sites, and species diversity showed highly at the farther sites of industrial complex, and also at the low layer, number of species, species diversity and evennes were low at the vicinity of industrialcomplex and species weakened to air pollution were disappearing. It was possible that forest vegetation would be changed from pinus spp. to community of a. firma and r. pseudoacacia.

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아파트 단지 외부공간의 형태구성 변화에 관한 연구 -서울 송파구 아파트 단지를 중심으로- (Study on the Change in the Forms and Compositions of Outdoor Planning of Apartment Complex)

  • 김동찬;김신원;김정주
    • 한국산업융합학회 논문집
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    • 제13권2호
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    • pp.113-124
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    • 2010
  • Since the 1970s the increased economy allowed population to concentrate on larger cities which facilitated the lack of apartment complex in the cities. In order to have the solution to the problem, apartment complex were expected to consider the efficiency of using its land. Therefore, The purpose of this study is to clarify the change of the Apartment Complex especially in the Forms and Compositions of outdoor planning of Apartment complex. As a result, the analysis of this researching process of them has shown us the following important characteristics in the change of the Apartment Complex.

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Empirical Analysis on Rao-Scott First Order Adjustment for Two Population Homogeneity test Based on Stratified Three-Stage Cluster Sampling with PPS

  • Heo, Sunyeong
    • 통합자연과학논문집
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    • 제7권3호
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    • pp.208-213
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    • 2014
  • National-wide and/or large scale sample surveys generally use complex sample design. Traditional Pearson chi-square test is not appropriate for the categorical complex sample data. Rao-Scott suggested an adjustment method for Pearson chi-square test, which uses the average of eigenvalues of design matrix of cell probabilities. This study is to compare the efficiency of Rao-Scott first order adjusted test to Wald test for homogeneity between two populations using 2009 Gyeongnam regional education offices's customer satisfaction survey (2009 GREOCSS) data. The 2009 GREOCSS data were collected based on stratified three-stage cluster sampling with probability proportional to size. The empirical results show that the Rao-Scott adjusted test statistic using only the variances of cell probabilities is very close to the Wald test statistic, which uses the covariance matrix of cell probabilities, under the 2009 GREOCSS data based. However it is necessary to be cautious to use the Rao-Scott first order adjusted test statistic in the place of Wald test because its efficiency is decreasing as the relative variance of eigenvalues of the design matrix of cell probabilities is increasing, specially more when the number of degrees of freedom is small.

ON A CLASS OF q-BI-UNIVALENT FUNCTIONS OF COMPLEX ORDER RELATED TO SHELL-LIKE CURVES CONNECTED WITH THE FIBONACCI NUMBERS

  • Ahuja, Om P.;Cetinkaya, Asena;Bohra, Nisha
    • 호남수학학술지
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    • 제42권2호
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    • pp.319-330
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    • 2020
  • We introduce a new subclass of q-bi-univalent functions of complex order related to shell-like curves connected with the Fibonacci numbers. We obtain the coefficient estimates and Fekete-Szegö inequalities for the functions belonging to this class. Relevant connections with various other known classes have been illustrated.