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1

Software reliability growth modeling for agile software development

100%

Rawat S. , Goyal N. , Ram M.

International Journal of Applied Mathematics and Computer Science

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2017

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tom Vol. 27, no. 4

777--783

EN

The frequent incremental release of software in agile development impacts the overall reliability of the product. In this paper, we propose a generic software reliability model for the agile process, taking permanent and transient faults into consideration. The proposed model is implemented using the NHPP (non-homogenous Poisson process) and the Musa model. The comparison of the two implementations yields an effective, empirical and reliable model for agile software development.

2

Finite element solutions for two-phase magneto-heat transfer in a particle-suspension through a non-Darcian porous channel with heat source and buoyancy effects

88%

Bhargava R. , Rawat S. , Takhar H. S. , Beg T. A. , Anwar Beg o.

International Journal of Applied Mechanics and Engineering

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2008

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tom Vol. 13, no 2

325-357

EN

We consider the steady, laminar natural convection heat transfer of a particulate suspension in an electrically-conducting fluid through a two-dimensional channel containing a non-Darcian porous material in the presence of a transverse magnetic field. The transport equations for both fluid and particle phases are formulated using a two-phase continuum model and a heat source term is included which simulates either absorption or generation. A set of transformations are implemented to reduce the partial differential equations for momentum and energy conservation (for both phases) from a two-dimensional coordinate system to a one-dimensional system. Finite element solutions are obtained for the transformed model. A comprehensive parametric study of the effects of the heat source parameter (E), Prandtl number (Pr), Grashof number (Gr), momentum inverse Stokes number (Skm), Darcy number (Da), Forchheimer number (Fs), particle loading parameter (PL), buoyancy parameter (B), Hartmann number (Ha), temperature inverse Stokes number (SkT), viscosity ratio [...], specific heat ratio [...], dimensionless particle-phase wall slip parameter [...] on the dimensionless fluid phase velocity (U), dimensionless particle phase velocity ( ), dimensionless fluid phase temperature [...] and the dimensionless temperature of particle phase [...] are presented graphically. In addition, we also describe numerical solutions for several special cases of the model, for example, the inviscid hydromagnetic two phase non-Darcian free convection, heat transfer [...], forced convection case (GrŽ0) etc. Fluid phase velocities are found to be strongly reduced by the magnetic field, Darcian drag and also Forchheimer drag; a lesser reduction is observed for the particle phase velocity field. The Prandtl number is shown to depress both the fluid temperature and particle phase temperature in the left hand side of the channel but to boost both temperatures at the right hand side of the channel [...]. The inverse momentum Stokes number is seen to reduce fluid phase velocities and increase particle phase velocities. The influence of other thermophysical parameters is discussed in detail and computations compared with previous studies. The model finds applications in MHD plasma accelerators, astrophysical flows, geophysics, geothermics and industrial materials processing.

3

Finite element modeling of laminar flow of a third grade fluid in a Darcy-Forcheimmer porous medium with suction effects

88%

Takhar H. S. , Bhargava R. , Rawat S. , Beg T. A. , Beg O. A.

International Journal of Applied Mechanics and Engineering

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2007

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tom Vol. 12, no 1

215-233

EN

A mathematical model to simulate the steady laminar flow of an incompressible, third grade, non-Newtonian fluid past an infinite porous plate embedded in a Darcy-Forcheimmer porous medium is presented. A number of special cases are examined for the governing nonlinear differential equation. The model is solved with appropriate boundary conditions using the finite element method. Velocity and velocity gradient are plotted graphically for variation in permeability (k), Forcheimmer parameter (b), third grade materiaI parameter (f3 3 ) , and suction effect (Vo). It is shown that velocities are generally decreased transverse to the plate surface with increasing Forcheimmer parameter; increasing permeability conversely boosts the velocities, as this corresponds to an increasingly fluid (Le., progressively less porous) regime. The third grade material parameter is also seen to substantially increase the velocities in the direction normal to the plate surface. The special case of a second order viscoelastic flow is also studied. The flow scenario finds applications in polymer extrusion processes, and other important industrial rheology systems.

4

Hairy root culture of Picrorhiza kurroa Royle ex Benth.: a promising approach for the production of picrotin and picrotoxinin

75%

Mishra J. , Bhandari H. , Singh M. , Rawat S. , Agnihotri M. , Mishra S. , Purohit S.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 5

EN

Picrorhiza kurroa Royle ex Benth. is an endangered plant producing various compounds of medicinal importance. Hairy roots of P. kurroa were obtained following cocultivation of shoot tip explants with Agrobacterium rhizogenes strains A 4 and PAT 405. Bacterial strain A 4 appeared to be better than the strain PAT 405 in terms of both growth of respective hairy root cultures and secondary metabolite production. The optimal growth of both the hairy root cultures occurred on halfstrength semisolid medium with 3% sucrose. Picrotin and picrotoxinin from the roots of wild type field grown plants were compared with 8-week-old hairy root cultures induced by the A 4 and PAT 405 strains of A. rhizogenes. Picrotin and picrotoxinin content were evaluated in hairy root cultures as well as roots of field grown plant of P. kurroa. In terms of the production of picrotin and picrotoxinin, the A 4 induced hairy roots appeared to be a better performer than the PAT 405 induced hairy root cultures. The picrotin and picrotoxinin content was highest in 8-week-old A 4 induced hairy roots (8.8 µg/g DW and 47.1 µg/g DW, respectively). Rapid growth of the hairy roots of P. kurroa with in vitro secondary metabolite production potential may offer an attractive alternative to the exploitation of this endangered plant species.

5

Identification and comparative analysis of Brassica juncea pathogenesis-related genes in response to hormonal, biotic and abiotic stresses

63%

Ali S. , Mir Z. A. , Tyagi A. , Bhat J. A. , Chandrashekar N. , Papolu P. K. , Rawat S. , Grover A.

Acta Physiologiae Plantarum

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2017

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tom 39

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nr 12

6

In vitro propagation, genetic and phytochemical assessment of Habenaria edgeworthii: an important Astavarga plant

63%

Giri L. , Jugran A. , Rawat S. , Dhyani P. , Andola H. , Bhatt I. D. , Rawal R. S. , Dhar U.

Acta Physiologiae Plantarum

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2012

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tom 34

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nr 3

EN

An efficient in vitro propagation protocol for Habenaria edgeworthii Hook. f. ex. Collett using seedderived callus was established. The maximum seed germination was observed in Murashige and Skoog (MS) medium supplemented with 1.0 µM α-naphthalene acetic acid (NAA). Induction of callus was achieved on full and ½-strength MS medium supplemented with 1.0 µM NAA. The highest number of shoot (11.9 shoots/explant) was achieved in MS medium supplemented with 0.1 µM 6-benzyladenine (BA) and 0.01 µM NAA. Further, elongated shoots when transferred to ½-strength MS rooting medium with different auxin concentrations induced roots (41.6–83.3%) and tubers (0–20.8%); however, a maximum of 87.5% rooting was achieved in a plant growth regulator (PGR)-free MS medium. Rooted shoots (plantlets) when transferred to a mixture of soil:sand:perlite (1:1:1 ratio) resulted in 68% survival. Inter-simple sequence repeats (ISSR) markers confirmed the genetic stability among regenerated plants. The phytochemical analysis of tissue culture-raised tubers showed higher phenolic content than wild tuber. The regeneration protocol developed in this study provides a basis for germplasm conservation and harnessing the total phenol and phenolic compounds of H. edgeworthii. Further, the methods can open avenues for application in other Orchidaceous plants of the Indian Himalayan region.