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Background: Sesame (Sesamum indicum L.) is a widely used oil seed crop throughout the world but its productivity is extremely low due to use of low yielding cultivars as well as biotic stress for the major pest Spilosoma obliqua Walker. But even today, farmers generally use broad-spectrum synthetic pesticides for their management injudiciously without considering any economic threshold (ET) limit and creates ecosystem crisis. So, time-based ecologically sustainable management of the said pest and selection of a superior cultivar of sesame was studied by stage-specific two-sex pooled life table and nutritional ecology of S. obliqua on three sesame cultivars (Rama, Shubhra and Amrit) along with their economic thresholds (ETs) in 2019. Results: The nutritional ecology and population dynamics of S. obliqua were significantly affected by the host phytoconstituents in terms of host suitability or susceptibility (Rama > Shubhra > Amrit). The mean EIL and ETL for S obliqua was 36.316 ± 3.911 and 33.243 ± 2.734 pests/m2, respectively on cv. Rama that were significantly (F2,6 = 5.421–5.435; P ≤ 0.042) lower than Shubhra and Amrit. For a single pest per m2 (30 ± 2 plants/m2) the possible time that can be taken to reach EIL (Ti) and ETL (Tt) were 39.132 ± 3.969 and 38.132 ± 3.969 days, respectively on cv. Rama which were also significantly (F2,6 = 26.551; P = 0.001) lower than the other cultivars. The seed yield and benefit cost ratio (BCR) were 857.099 ± 0.000 (Kg/ha) and 0.607 ± 0.000, respectively for cv. Rama that were significantly (P < 0.05) lower than the others. Conclusions: It will enable growers to find the most preferred cultivar (Rama > Shubhra > Amrit) based on BCR values irrespective of their biotic resistance (Rama < Shubhra < Amrit) due to host antibiosis. Even, the ETs-based time series for judicious management of the pest along with carbon sequestration efficiency (CSE) will also support superiority of the cultivars (Rama > Shubhra > Amrit) towards climate smart pest management (CSPM) of sesame and or other such crops in near future. [ABSTRACT FROM AUTHOR] more...

In this paper, we analyzed charged particle transverse momentum spectra in high multiplicity events in proton–proton and nucleus–nucleus collisions at LHC energies from the ALICE experiment using the color string percolation model (CSPM). The color reduction factor and associated string density parameters are extracted for various multiplicity classes in p p collisions and centrality classes for heavy-ion collisions at various LHC energies to study the effect of collision geometry and collision energy. These parameters are used to extract the thermodynamical quantities temperature and the energy density of the hot nuclear matter. A universal scaling is observed in initial temperature when studied as a function of charged particle multiplicity scaled by transverse overlap area. From the measured initial energy density and the initial temperature T, a dimensionless quantity / T 4 is constructed which is used to obtain the degrees of freedom (DOF) of the deconfined phase. A two-step behavior and a sudden increase in DOF of ∼ 47 for the ideal gas, above the hadronization temperature (T ≈ 210 MeV), are observed in case of heavy-ion collisions at LHC energies. [ABSTRACT FROM AUTHOR] more...

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Abstract: In Problems with large deformation including fracture and fragmentation, the grid based methods have some limitations which make them unsuitable for simulating these types of problems. An example is extreme mesh distortion in a lagrangian approach like Finite element method. Another situation is the inability of Eulerian based formulations in tracking the history of a desired physical property at the interface of multi materials including impact problems. A promising solution is taking the advantage of meshless and particle based methods which do not use any kind of grid in the physical domain of problem. In this paper, corrective smoothed particle algorithm (CSPM) as a meshless particle method is used to study the mechanical behavior of a ceramic–metal functionally graded material (FGM) under high velocity impact conditions. A mixed strength model with sigmoid formulation has been used to describe both yielding and fracture phenomena in the FGM. The strength model includes the JC dynamic yield relation and Johnson–Holmquist–Beissel (JHB) fracture model with a continuum damage description approach. An efficient renormalization in continuity density approach is used to improve the smoothed particle hydrodynamics (SPH) approximation of boundary physical variables. This study shows that CSPM in combination with the proper strength model describing the FGM dynamic behavior, can predict the mixed plastic and brittle response of a ceramic–metal functionally graded material under high impact velocities. [Copyright &y& Elsevier] more...

Abstract: The capability to track material interfaces, especially in fluid structure problems, is among the advantages of meshless methods. In the present paper, the Smoothed Particle Hydrodynamics (SPH) method is used to investigate elastic–plastic deformation of AL and ceramic–metal FGM (Functionally Graded Materials) plates under the impact of water in a fluid–solid interface. Instead of using an accidental repulsive force which is not stable at higher pressures, a new scheme is proposed to improve the interface contact behavior between fluid and solid structure. This treatment not only prevents the interpenetration of fluid and solid particles significantly, but also maintains the gap distance between fluid and solid boundary particles in a reasonable range. A new scheme called corrected smooth particle method (CSPM) is applied to both fluid and solid particles to improve the free surface behavior. In order to have a more realistic free surface behavior in fluid, a technique is used to detect the free surface boundary particles during the solution process. The results indicate that using the proposed interface algorithm together with CSPM correction, one can predict the dynamic behavior of FGM plates under the impact of fluid very promisingly. [Copyright &y& Elsevier] more...

Abstract: In this paper, the corrective smoothed particle method (CSPM) numerical algorithm as a modification of traditional SPH particle method has been employed to predict fracture and fragmentation in ceramics using a thermo-mechanical basis under hypervelocity impact conditions. In order to study the brittle behavior in ceramic, the JHB computational constitutive model which considers phase transition in a solid continuum has been applied. An appropriate heat conduction equation has been coupled with the Johnson–Cook yield criteria in order to get more accurate temperature field especially in impact zone which consequently gives a more exact solution in such problems coming with highly produced magnitude of pressure and temperature in the material. It has been shown that implementation of the CSPM scheme with a thermo-mechanical basis can predict the brittle fracture and fragmentation in ceramics under hyper velocity impact conditions. [Copyright &y& Elsevier] more...

A meshless shell method for large deformation and a linear relation between the Cauchy stress tensor and the Almansi strain tensor based on the corrective smoothed particle method (CSPM) is presented in this paper. Due to the use of the shell theory, only one layer of particles in the reference plane is required to discretize the shell model. The CSPM combining the kernel estimate with the Taylor series expansion is adopted, which resolves the general problems of low precision and particle deficiency in standard smoothed particle hydrodynamics (SPH). The discrete governing equations of the shell in the strong form are derived using the conservation condition and the CSPM interpolation function. Aiming at the sore point of the free boundary in the meshless method, the developed model enables the modified governing equations to automatically satisfy the free boundary condition without additional treatment. Moreover, the total Lagrangian kernel function and stress points are employed to eliminate tensile instability and instability induced by the rank deficiency. Finally, several numerical examples are used to verify the validity and accuracy of the meshless shell model. [ABSTRACT FROM AUTHOR] more...

This paper presents a meshless model for quasi-static and dynamic analysis of a three-dimensional Timoshenko beam with geometric nonlinearity. A general mathematical formulation is constructed based on the corrective smoothed particle method (CSPM), which can correct the low precision and completeness deficiency of the standard smoothed particle hydrodynamics(SPH) method. The discrete governing equations as well as the boundary conditions in strong form for the three-dimensional beam are then derived by using the conservation conditions and the CSPM interpolation function. The developed model enables one to expediently discretize the geometric nonlinear beam with only a row of particles at the central axis and to automatically satisfy the free boundary condition without any additional treatment. Moreover, Lagrangian kernel function and stress points are adopted to eliminate tensile instability and instability induced by the rank deficiency within the particle methods. Finally, comparisons with several results obtained from the existing literature are provided to demonstrate the validity and potential of the present procedure. • A three-dimensional meshless beam model with geometric nonlinearity is presented. • The beam formulation is constructed using the corrective smoothed particle method. • A free boundary treatment method is proposed for the meshless beam formulation. [ABSTRACT FROM AUTHOR] more...