• Title/Summary/Keyword: Third-order

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Theroetical Study of the Nonlinear Optical Properties of Thiophene, Furan, Pyrrole, (1,2,4-triazole), (1,3,4-oxadiazole), and (1,3,4-thiadiazole) Monomers and Oligomers

  • 최우성;김태원;정승우;김철주
    • Bulletin of the Korean Chemical Society
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    • v.19 no.3
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    • pp.299-307
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    • 1998
  • PM3 semiempirical calculations were carried out to study the frequency-dependent nonlinear optical properties of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-oxadiazole, and (1,3,4)-thiadiazole monomers and oligomers. The longitudinal component, αxx, is the largest of three principle components. On the other hand, the out-of-plane component, αzz, is the smallest. Moreover, the out-of-plane component (αzz) of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-oxadiazole, and (1,3,4)-thiadiazole monomers show constant changes with increasing optical frequencies. The frequency-dependent first- order polarizabilities increase in the order: thiophene > (1,2,4)-triazole > pyrrole > furan > (1,3,4)-thiadiazole > (1,3,4)-oxa-diazole monomers and oligomers. The effects of β(-2ω;ω,ω) (SHG) shows a larger dispersion compared with (-ω;ω,0) (EOPE) and β(0;-ω,ω) (OR). The second- order polarizabilities of thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-thiadiazole, and (1,3,4)-oxadiazole monomers for the various second- order effects have the order: β(-2ω;ω,ω) (SHG) > β(-ω;ω,0) (EOPE) > β(0;-ω,ω) (OR) and thiophene > pyrrole > (1,2,4)-triazole > furan > 1,3,4-thiadiazole > 1,3,4-oxadiazole monomers. The third- order polarizabilities for the various third- order effects have the following order: γ(-3ω;ω',ω,ω) (THG) > γ(-2ω;0,ω,ω) (EFISHG) > γ(-ω;ω',-ω,ω) (IDRI) > γ(-ω;0,0,ω) (OKE). The effects of THG increase rapidly with increasing optical frequencies compared with the other effects. In particular, OKE effects increase most slowly with increasing optical frequencies. Also, the effects of THG for thiophene, furan, pyrrole, (1,2,4)-triazole, (1,3,4)-thiadiazole, and (1,3,4)-oxadiazole oligomers show the order thiophene > (1,2,4)-triazole > furan > pyrrole > (1,3,4)-thiadiazole > (1,3,4)-oxadiazole oligomers. In particular, the third- order polarizabilities of thiophene and (1,3,4)-thiadiazole oligomers are about four and three times larger than those of (1,3,4)-oxadiazole and (1,2,4)-triazole oligomer, respectively.

The Phase Noise Prediction and 1/f Noise Modeling of Frequency Synthesizer (주파수합성기의 Phase Noise 예측 및 1/f Noise Modeling)

  • 김형도;성태경;조형래
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.180-185
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    • 2000
  • In this paper, we designed 2303.15MHz Sequency synthesizer for the purpose of the phase noise prediction. For the modeling of phase noise Oersted in the designed system through inooducing the noise-modeling method suggested by Lascari we analyzied a variation of phase noise as according as that of offest frequency. Especially, for the third-order system of the PLL among some kinds of phase noise generated from VCO we analyzed the aspect of 1/f-noise appearing troubles in the low frequency band. Since it is difficult to analyze mathematically 1/f-noise in the third-order system of the PLL, introducing the concept of pseudo-damping factor has made an ease of the access of the 1/f-noise variance. we showed a numerical formula of 1/f-noise variance in the third-order system of the PLL which is compared with that of 1/f-noise variance in the second-order system of the PLL

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A CLINICAL STUDY OF FACIAL BONE FRACTURE FOR FIVE YEARS AT SEONG NAM CITY (성남지역의 안면골 골절에 관한 임상적 연구)

  • Oh, Seong-Seob;Son, Seong-Joon;Kim, Il-Kyu
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.17 no.4
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    • pp.396-406
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    • 1995
  • This is a clinical and retrospective study who sustained a total of 306 maxillofacial bone fracture and who were treated in our department between 1990-1994. This results were obtained as follows : 1. The ratio of men to women was 3.2 : 1. 2. The age frequency was the highest in the third decade(35%). That of man was the highest in the third decade but that of women in the fourth decade. 3. In respect of incidence, the number of patients has not been increased year after year. There were the highest frequency in September and the lowest frequency in January. 4. The most frequent cause of facial bone fracture was fall down(40.2%), traffic accident(28.1%), fist blow(20.9%), industrial accident(6.2%) and others in order. 5. The most common location of facial bone fracture was mandible(69%), maxillar with zygoma and zygoma in order of frequency. 6. The age frequency of mandible was the third decade(36.5%), the fourth decade(23.2%) and the fourth decade(22.2%) and the fifth decade(15.6%) in order. 7. In respect of incidence of associated injuries, the ratio of absence to presence was 0.7 : 1. 8. In 306 patients of facial bone fracture, the frequency of associated injuries was laceration, extrimities, chest in order.

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Analytical solution for nonlocal buckling characteristics of higher-order inhomogeneous nanosize beams embedded in elastic medium

  • Ebrahimi, Farzad;Barati, Mohammad Reza
    • Advances in nano research
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    • v.4 no.3
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    • pp.229-249
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    • 2016
  • In this paper, buckling characteristics of nonhomogeneous functionally graded (FG) nanobeams embedded on elastic foundations are investigated based on third order shear deformation (Reddy) without using shear correction factors. Third-order shear deformation beam theory accounts for shear deformation effects by a parabolic variation of all displacements through the thickness, and verifies the stress-free boundary conditions on the top and bottom surfaces of the FG nanobeam. A two parameters elastic foundation including the linear Winkler springs along with the Pasternak shear layer is in contact with beam in deformation, which acts in tension as well as in compression. The material properties of FG nanobeam are supposed to vary gradually along the thickness and are estimated through the power-law and Mori-Tanaka models. The small scale effect is taken into consideration based on nonlocal elasticity theory of Eringen. Nonlocal equations of motion are derived through Hamilton's principle and they are solved applying analytical solution. Comparison between results of the present work and those available in literature shows the accuracy of this method. The obtained results are presented for the buckling analysis of the FG nanobeams such as the effects of foundation parameters, gradient index, nonlocal parameter and slenderness ratio in detail.

A method for linearizing nonlinear system by use of polynomial compensation

  • Nishiyama, Eiji;Harada, Hiroshi;Kashiwagi, Hiroshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.597-600
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    • 1997
  • In this paper, the authors propose a new method for linearizing a nonlinear dynamical system by use of polynomial compensation. In this method, an M-sequence is applied to the nonlinear system and the crosscorrelation function between the input and the output gives us every crosssections of Volterra kernels of the nonlinear system up to 3rd order. We construct a polynomial compensation function from comparison between lst order Volterra kernel and high order kernels. The polynomial compensation function is, in this case, of third order whose coefficients are variable depending on the amplitude of the input signal. Once we can get compensation function of nonlinear system, we can construct a linearization scheme of the nonlinear system. That is. the effect of second and third order Volterra kernels are subtracted from the output, thus we obtain a sort of linearized output. The authors applied this method to a saturation-type nonlinear system by simulation, and the results show good agreement with the theoretical considerations.

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THREE POINT BOUNDARY VALUE PROBLEMS FOR THIRD ORDER FUZZY DIFFERENTIAL EQUATIONS

  • Murty, M.S.N.;Kumar, G. Suresh
    • Journal of the Chungcheong Mathematical Society
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    • v.19 no.1
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    • pp.101-110
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    • 2006
  • In this paper, we develop existence and uniqueness criteria to certain class of three point boundary value problems associated with third order nonlinear fuzzy differential equations, with the help of Green's functions and contraction mapping principle.

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ON AN EQUATION CONNECTED WITH THE THEORY FOR SPREADING OF ACOUSTIC WAVE

  • Zikirov, O.S.
    • East Asian mathematical journal
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    • v.27 no.1
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    • pp.51-65
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    • 2011
  • In the paper, we study questions on classical solvability of nonlocal problems for a third-order linear hyperbolic equation in a rectangular domain. The Riemann method is applied to the Goursat problem and solution is obtained in the integral form. Investigated problems are reduced to the uniquely solvable Volterra-type equation of second kind. Influence effects of coefficients at lowest derivatives on correctness of studied problems are detected.

THE LOWER BOUND OF THE THIRD-ORDER INTERMODULATION PRODUCTS (3차 INTERMODULATION의 LOWER BOUND에 관한 연구)

  • Jang, Ki-Soong;Lee, Young-Choul
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.859-863
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    • 1987
  • In this paper, a relationship between difference triangular sets and sum triangular sets is developed to evaluate the weighted number of the third-order intermodulation products. In addition, a lower bound of the intermodulation products falling into the worst signal channel has been derived using the relationship between difference triangular sets and sum triangular sets. The formulas of the lower bound are useful for estimating the intermodulation impairment level in satellite communication systems.

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Analysis of the linear Amplifier/Analog-Digital Converter Interface in a Digital Microwave Wideband Receiver (디지털 광대역 마이크로 웨이브 수신기에서의 선형 증폭기와 ADC 접 속의 해석)

  • 이민혁;장은영
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.110-113
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    • 1998
  • An analysis of the relationship between a linear amplifier chain and an analog-to-digital converter(ADC) in a digital microwave widevand receiver, with respect to sensitivity and dynamic range issues, is presented. The effects of gain, third-order intermodulation products and ADC characteristics on the performance of the receiver are illustrated and design criteria for the linear amplifier chain given a specified ADC are developed. A computer program is used to calculate theretical receiver performance based on gain and third-order intermodulation product selections. Simulated results are also presented and compared with theoretical values.

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OSCILLATION AND ASYMPTOTIC STABILITY BEHAVIOR OF A THIRD ORDER LINEAR IMPULSIVE EQUATION

  • WAN ANHUA;MAO WEIHUA
    • Journal of applied mathematics & informatics
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    • v.18 no.1_2
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    • pp.405-417
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    • 2005
  • In this paper, the oscillation and asymptotic stability behavior of a third order linear impulsive equation are investigated. A lemma is presented to deal with the sign relation of the nonoscillatory solutions and their derived functions. By the lemma explicit sufficient conditions are obtained for all solutions either oscillating or asymptotically tending to zero. Two illustrative examples are proposed to demonstrate the effectiveness of the conditions.