• 제목/요약/키워드: half-order

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Oscillation Criteria of Second-order Half-linear Delay Difference Equations

  • Saker, S.H.
    • Kyungpook Mathematical Journal
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    • 제45권4호
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    • pp.579-594
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    • 2005
  • In this paper, we will establish some new oscillation criteria for the second-order half-linear delay difference equation $${\Delta}(Pn ({\Delta}Xn)^{\gamma})+q_nx_\array{{\gamma}\\n-{\sigma}}=0,\;n{\geq}n_0$$, where ${\gamma}>0$ is a quotient of odd positive integers. Our results in this paper are sharp and improve some of the well known oscillation results in the literature. Some examples are considered to illustrate our main results.

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들깻잎에서 Triazole계 살균제의 생물학적 반감기와 물리화학적 특성과의 상관관계 (Correlation between physicochemical properties and biological half-life of triazole fungicides in perilla leaf)

  • 이상협;곽세연;황정인;김효정;김태화;김장억
    • Journal of Applied Biological Chemistry
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    • 제62권4호
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    • pp.407-415
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    • 2019
  • 들깻잎에 살포된 triazole계 살균제 6종에 대하여 생물학적 반감기를 산출하고 분해 및 소실 속도를 확인하였으며, 통계분석으로 생물학적 반감기와 농약의 물리화학적 특성간의 상관관계를 확인하였다. 확립된 분석법으로 6종 농약의 회수율 시험 결과 84.8-104.9%로 잔류농약분석법 기준을 만족하였다. 들깻잎에 살포한 농약 6종의 생물학적 반감기는 first-order kinetics model으로 산출하였으며, 그 결과 6.4-15.1일로 나타났다. 산출된 생물학적 반감기와 6종의 농약의 물리화학적 특성을 주성분 분석으로 상관성을 확인하였을 때, pKa, Log P 및 생물학적 반감기가 PC1에 영향을 받아 상관성이 있는 것으로 나타났다. Spearman rank-order correlation으로 생물학적 반감기와 물리화학적 특성간의 상관계수를 산출하였을 때, 생물학적 반감기와 pKa는 R2 = -0.928, p <0.01로 나타나, 생물학적 반감기는 pKa와 상관성이 있는 것으로 나타났다.

Effect of fractional order on energy ratios at the boundary surface of elastic-piezothermoelastic media

  • Kumar, Rajneesh;Sharma, Poonam
    • Coupled systems mechanics
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    • 제6권2호
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    • pp.157-174
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    • 2017
  • In the present investigation reflection and transmission of plane waves at an elastic half space and piezothermoelastic solid half space with fractional order derivative is discussed. The piezothermoelastic solid half space is assumed to have 6 mm type symmetry and assumed to be loaded with an elastic half space. It is found that the amplitude ratios of various reflected and refracted waves are functions of angle of incidence, frequency of incident wave and are influenced by the piezothermoelastic properties of media. The expressions of amplitude ratios and energy ratios are obtained in closed form. The energy ratios are computed numerically using amplitude ratios for a particular model of graphite and Cadmium Selenide (CdSe). The variations of energy ratios with angle of incidence are shown graphically. The conservation of energy across the interface is verified. Some cases of interest are also deduced from the present investigation.

탄성지반 위의 축대칭 하중을 받는 원판의 접촉응력 해석에 관한 연구 (The Study on the Determination of the Contact Area of the Circular Plate Resting on Elastic Half-space under Axisymmetric Loading)

  • 조현영;정진환;김성철
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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    • pp.87-94
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    • 1997
  • The circular plate resting on Boussinesq's half-space model under axisymmetric loading is studied by a finite element procedure to evaluate the distribution of contact pressure between plate and elastic half-space. The displacement of half-space due to axisymmetric surface loading can be evaluated by double integration of Boussinesq's solution. On that case the analytical integration can be executed for the radial direction but the analytical integration for the circumferential direction is impossible and the numerical integration should be considered. With the radial integration we can get non-dimensional function. Then the numerical integration for the formula is executed for the circumferential direction and the results are approximated 5th order Polynomials by using the least square method. With these 5th order approximate formula, the flexibility matrix of half-space is constructed as the coefficient matrix of nodal contact pressure by the finite element procedures. Iteration procedures are attempted by using this method to determine the separated region.

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1차원 및 2차원 선형 반대역 필터의 설계에 관한 연구 (Design of 1-D and 2-D Linear-phased Half-band Filters)

  • 김대영;이병기
    • 전자공학회논문지B
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    • 제31B권5호
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    • pp.42-49
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    • 1994
  • In this paper we consider efficient 1-D and 2-D linear-phased half-band filter designs. We first introduce a new derivation of the existing Vaidynathan-Nguyen 's half-band filter design method, which verifies that the design provides optimal half-band filters. We then propose an approximately-linear-phased IIR half-band filter design method, which is based on the all-pass equalizer design with the linear phase -$\omega$/2. Finally, we propose an efficient method to design optimal 2-D half-band filters, for which we utilize a 2-D all pass prototype filter of half the order of the desired 2-D half-band filters.

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Noninformative priors for the ratio of the scale parameters in the half logistic distributions

  • Kang, Sang-Gil;Kim, Dal-Ho;Lee, Woo-Dong
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.833-841
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    • 2012
  • In this paper, we develop the noninformative priors for the ratio of the scale parameters in the half logistic distributions. We develop the first and second order matching priors. It turns out that the second order matching prior matches the alternative coverage probabilities, and is a highest posterior density matching prior. Also we reveal that the one-at-a-time reference prior and Jeffreys' prior are the second order matching prior. We show that the proposed reference prior matches the target coverage probabilities in a frequentist sense through simulation study, and an example based on real data is given.

Kinetic models에 의한 딸기 중 농약의 생물학적 반감기 비교와 생산단계잔류허용기준 설정 (Field tolerance of pesticides in the strawberry and comparison of biological half-lives estimated from kinetic models)

  • 박동식;성기용;최규일;허장현
    • 농약과학회지
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    • 제9권3호
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    • pp.231-236
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    • 2005
  • 본 연구는 생산단계의 딸기에 4가지 살균제(tolclofos-m, folpet, procymidone, triflumizole)를 수확 10일전 안전사용 기준량으로 처리한 후 잔류량을 파악하였고, 이것을 근거로 6 가지 kinetic models(first order, zero order, second order, power function model, elovich model, parabolic model)에 따른 반감기를 비교하였다. 최적의 모델로 판명된 first order kinetic model로부터 구한 반감기를 이용하여 생산단계잔류허용기준(field tolerance)을 설정, 제시하였다. 잔류분석법의 적합성 판단을 위한 회수율 실험에서는 $85.1{\sim}105.0%$ 범위를 보였으며, 4 가지 약제 모두 약제 처리 5일 후 평균 73% 이상 소실되었다. 잔류량과 시간과의 상관관계는 first order kinetic model에서 가장 높은 결정계수값을 보였으며, 이를 이용하여 산출한 반감기로 생산단계 잔류허용기준(안)을 설정하였다. 이와 같은 결과는 최적의 kinetic model로 반감기를 산출해야 한다는 이론적 근거를 제시하는 것이며, 수확 후 또는 유통 중의 잔류허용기준뿐만 아니라 생산단계에서도 허용기준을 마련하여 부적합 품목을 사전에 차단할 수 있는 기준설정의 예로서 안전 농산물 공급과 농가소득에 크게 기여할 수 있는 기초자료가 될 것이라 사료된다.

미세 방전 가공을 이용한 반구형 전극 제작 (Half spherical electrode machining in micro EDM)

  • 김기현;주종남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.1080-1084
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    • 2001
  • In manufacturing a micro die with half spherical cavity by MEDM, it is necessary to prepare an electrode with the same shape. This paper suggests a simple method to manufacture a half spherical electrode based on tool wear. The tool wears more rapidly at the edge of a cylindrical electrode. In order to make a half spherical micro electrode, cylindrical electrode was fed into the workpiece by the distance of its radius. The d/R(depth/Radius) value varied with respect to capacitance and electrode diameter. The smaller the size of electrode was, the closer the electrode tip geometry approached to a half sphere.

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지명 '명량(鳴梁)'과 '노량(露梁)'의 어원 고찰 (A Study on the Etymology of the Place Names 'Myeongryang' and 'Noryang')

  • 김진식
    • 인문언어
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    • 제8집
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    • pp.241-263
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    • 2006
  • Place names are generally composed of first half and second half, whether the originality of those names comes from Korean or Chinese. The first half, modifying the second half, represents the naming flexibility of the name, while the second half of the name points out its directive object, which refers to a branch of the name. For example, 'Myeong' in 'Myeongryang' and 'No' in 'Noryang' represent their naming flexibility while 'Ryang', constituting the second half, points out the name's directive object. The purpose of this study was to investigate the etymology of place names, 'Myeongryang' and 'Noryang', by figuring out the meanings of those two elements. In order to search for the meaning of the second half, 'Ryang', other examples presented in the related literature have been examined. The finding indicated that 'Ryang' means 'dol', or 'do', which refers to 'moon(door)'. Furthermore, it is found out that the meaning of 'Ryang' has been transferred from 'dol' or 'do' to 'moon(door)', furthermore, to the straits. Upon looking into the origins of those names on the field, it is interpreted that 'Myeong Ryang' has been meant as a door in which huge and rough waves cry out, and 'No Ryang' has been meant as a door in which huge and rough waves rise up.

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On Nonovershooting or Monotone Nondecreasing Step Response of Second-Order Systems

  • Kwon, Byung-Moon;Lee, Myung-Eui;Kwon, Oh-Kyu
    • Transactions on Control, Automation and Systems Engineering
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    • 제4권4호
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    • pp.283-288
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    • 2002
  • This paper has shown that the impulse and the unit step responses of 2nd-order systems can be computed by an analytic method. Three different 2nd-order systems are investigated: the prototype system, the system with one LHP(left half plane) real zero and the system with one RHP(right half plane) real zero. It has also shown that the effects of the LHP or the RHP zero are very serious when the zero is getting closer to the origin on the complex plane. Based on these analytic results, this paper has presented two sufficient and necessary conditions for 2nd-order linear SISO(single-input/single-output) stable systems to have the nonovershooting and the monotone nondecreasing step response, respectively. The latter condition can be extended to the sufficient conditions for the monotone nondecreasing step response of high-order systems.