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Fractional order thermoelastic wave assessment in a two-dimension medium with voids

  • Hobiny, Aatef D.;Abbas, Ibrahim A.
    • Geomechanics and Engineering
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    • v.21 no.1
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    • pp.85-93
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    • 2020
  • In this article, the generalized thermoelastic theory with fractional derivative is presented to estimate the variation of temperature, the components of stress, the components of displacement and the changes in volume fraction field in two-dimensional porous media. Easily, the exact solutions in the Laplace domain are obtained. By using Laplace and Fourier transformations with the eigenvalues method, the physical quantities are obtained analytically. The numerical results for all the physical quantities considered are implemented and presented graphically. The results display that the present model with the fractional derivative is reduced to the Lord and Shulman (LS) and the classical dynamical coupled (CT) theories when the fractional parameter is equivalent to one and the delay time is equal to zero and respectively.

Analysis of the False Diffusion Effects in Numerical Simulation of Diesel Spray Impinging on Inclined Walls (경사진 벽충돌 디젤 분무에 대한 수치해석에서 오류확산이 미치는 영향)

  • Gwon, H.R.;Lee, S.H.
    • Journal of ILASS-Korea
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    • v.13 no.1
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    • pp.22-27
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    • 2008
  • The false diffusion occurs generally when the flow is oblique to the grid lines and when there is a non-zero gradient of the dependent variable in the direction normal to the flow. This numerical problem can overestimate diffusion terms in the continuous phase, causing the numerical inaccuracy for the simulation of impinging sprays on inclined walls because most of spray calculation uses rectangular grid system. Therefore, the main objective of this article is to investigate numerically the influence of false diffusion on numerical simulation for spray-wall impingement on inclined walls. It is found that unlike the spray impingement normal to the wall, the numerical diffusion exists in the case when diesel sprays impinge on the inclined walls with different angles. The results show that the correction function should be considered for accurate prediction of spray penetration length and more elaborate numerical schemes should be utilized to reduce the false diffusion.

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An optimal flow path design & minimum numbers of vehicle for AGVS (최적 경로와 최소 AGV 댓수를 갖는 AGVS에 관한 연구)

  • 오명진;김진홍
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.18 no.36
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    • pp.105-112
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    • 1995
  • This paper presents that model 1 is to show an approach to determining unidirection or bidirection of the optimal flow path design, model 2 is to show the design of an AGV can determine the minimum number of required vehicles. Our purposes of this article are that first, it is easy to see that computationlly advanced efficient procedure with some pairwises of comparision, zero-one integer and northwest rule by using, second, to determine the minimum number of vehicles in the layout for manufacturing facility, we used a coefficient ratio with moved numbers of loaded & unloaded vehicles between stations and available time of AGV's capacity for per shift per vehicle. Example is presented to demonstrate the approach.

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An Experimental on Cellular Instability and Laminar Burning Velocity of SNG Fuel (SNG 연료의 셀 불안정성 및 층류연소속도에 관한 실험적 연구)

  • Kim, Dongchan;Jo, Junik;Lee, Keeman
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.109-112
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    • 2015
  • This article describes a cellular instability and laminar burning velocity of simulated synthetic natural gas(SNG) including 3% hydrogen. In this study, experimental apparatus is employed using cylindrical bomb combustor, and investigation is carried out with high speed camera and Schlieren system. The cellular instability is caused by the buoyancy, hydrodynamic instability. Unstretched burning velocity can be determined by extrapolated stretch rate of zero point from measured results. These results were also compared with numerical calculation by Chemkin package with GRI 3.0, USC-II, WANG, C3 Fuel mechanism. As an experimental conditions, equivalence ratios was adjusted from 0.8 to 1.3. From results of this work, the one was found that the cellular instability has occurred by effect of thermal expansion rate and flame thickness. As the other results, unstretched laminar burning velocity was best coincided with GRI 3.0 mechanism.

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Citic Tower Construction Key Technology

  • Xu, Lishan
    • International Journal of High-Rise Buildings
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    • v.8 no.3
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    • pp.185-192
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    • 2019
  • Citic Tower is the first over-500 m-tall super highrise building in the world, located in the high seismic intensity area with paek ground acceleration over 0.2g in 475 years. This project is unique in its complexity, large volume, and challenging site conditions (zero site for construction). The traditional techniques can hardly meet safty, quality and schedule requirements of the construction. This article introduces the key construction technologies that are innovatively developed and applied in Citic Tower project construction, including intelligent super-high-rise building integrated construction platform system, independently developed by the CCTEB; Jump-Lift Elevator, which is the first of the kind with service height over 500 meters; combined temporary-and-permanent fire protection systems. The BIM technology is also applied in this project. Through technical innovation, and utilization of technologies, construction speed and safety had been greatly improved.

The transmuted GEV distribution: properties and application

  • Otiniano, Cira E.G.;de Paiva, Bianca S.;Neto, Daniele S.B. Martins
    • Communications for Statistical Applications and Methods
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    • v.26 no.3
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    • pp.239-259
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    • 2019
  • The transmuted generalized extreme value (TGEV) distribution was first introduced by Aryal and Tsokos (Nonlinear Analysis: Theory, Methods & Applications, 71, 401-407, 2009) and applied by Nascimento et al. (Hacettepe Journal of Mathematics and Statistics, 45, 1847-1864, 2016). However, they did not give explicit expressions for all the moments, tail behaviour, quantiles, survival and risk functions and order statistics. The TGEV distribution is a more flexible model than the simple GEV distribution to model extreme or rare events because the right tail of the TGEV is heavier than the GEV. In addition the TGEV distribution can adjusted various forms of asymmetry. In this article, explicit expressions for these measures of the TGEV are obtained. The tail behavior and the survival and risk functions were determined for positive gamma, the moments for nonzero gamma and the moment generating function for zero gamma. The performance of the maximum likelihood estimators (MLEs) of the TGEV parameters were tested through a series of Monte Carlo simulation experiments. In addition, the model was used to fit three real data sets related to financial returns.

ON STRONGLY RIGHT 𝜋-DUO RINGS

  • Cheon, Jeoung Soo;Nam, Sang Bok;Yun, Sang Jo
    • Journal of the Chungcheong Mathematical Society
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    • v.33 no.3
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    • pp.327-337
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    • 2020
  • This article continues the study of right 𝜋-duo rings, concentrating on the situation of nonzero powers. For this purpose we introduce the concept of strongly right 𝜋-duo and examine the structure of strongly right 𝜋-duo in relation to various ring properties that play important roles in ring theory. It is proved for a strongly right 𝜋-duo ring R that if the upper (lower) nilradical of R is zero then R is reduced. Various kinds of examples are examined in relation to the questions raised in the procedure.

Optimized Location Selection of Active Mounting System Applied to 1D Beam Structure

  • Kim, Byeongil
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.4_1
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    • pp.505-511
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    • 2022
  • The objective of this article is finding optimized locations of active mounts applied to 6-DOF beam structure with two active paths. When sinusoidal excitation forces are applied to the beam structure, secondary forces from two active mounts which can minimize (ideally becoming zero) transmitted forces are calculated mathematically and the vibration attenuation performance is validated through computer simulations. When the force applied to two active mounts are relatively low, those specific locations are considered as optimized location of active mounting system. As the location of mount changes, amplitude and phase of secondary forces in each path are analyzed with 3D plots. Based on the simulation results, a criterion for selecting mounting location is suggested and it would be very useful for selecting actuators for active mounts appropriately.

The Geometry of 𝛿-Ricci-Yamabe Almost Solitons on Paracontact Metric Manifolds

  • Somnath Mondal;Santu Dey;Young Jin Suh;Arindam Bhattacharyya
    • Kyungpook Mathematical Journal
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    • v.63 no.4
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    • pp.623-638
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    • 2023
  • In this article we study a 𝛿-Ricci-Yamabe almost soliton within the framework of paracontact metric manifolds. In particular we study 𝛿-Ricci-Yamabe almost soliton and gradient 𝛿-Ricci-Yamabe almost soliton on K-paracontact and para-Sasakian manifolds. We prove that if a K-paracontact metric g represents a 𝛿-Ricci-Yamabe almost soliton with the non-zero potential vector field V parallel to 𝜉, then g is Einstein with Einstein constant -2n. We also show that there are no para-Sasakian manifolds that admit a gradient 𝛿-Ricci-Yamabe almost soliton. We demonstrate a 𝛿-Ricci-Yamabe almost soliton on a (𝜅, 𝜇)-paracontact manifold.

ON SOME NEW SOLITONS SOLUTIONS OF NONLINEAR COMPLEX GINZBURG-LANDAU EQUATION SOLVED BY MODIFIED JACOBI ELLIPTIC FUNCTIONS METHOD

  • AICHA BOUSSAHA;HALIM ZEGHDOUDI;RAMAN VINOTH
    • Journal of applied mathematics & informatics
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    • v.42 no.2
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    • pp.391-398
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    • 2024
  • This article explains how solitons propagate when there is a detuning factor involved. The explanation is based on the nonlinear complex Ginzburg-Landau equation, and we first consider this equation before systematically deriving its solutions using Jacobian elliptic functions. We illustrate that one specific ellipticity modulus is on the verge of occurring. The findings from this study can contribute to the understanding of previous research on the Ginzburg-Landau equation. Additionally, we utilize Jacobi's elliptic functions to define specific solutions, especially when the ellipticity modulus approaches either unity or zero. These solutions correspond to particular periodic wave solitons, which have been previously discussed in the literature.