Indian Institute of Technology Indore

About: Indian Institute of Technology Indore is a education organization based out in Indore, Madhya Pradesh, India. It is known for research contribution in the topics: Computer science & Chemistry. The organization has 1606 authors who have published 4803 publications receiving 66500 citations.

A Particle Module for the PLUTO Code: I - an implementation of the MHD-PIC equations.

Abstract: We describe an implementation of a particle physics module available for the PLUTO code, appropriate for the dynamical evolution of a plasma consisting of a thermal fluid and a non-thermal component represented by relativistic charged particles, or cosmic rays (CR). While the fluid is approached using standard numerical schemes for magnetohydrodynamics, CR particles are treated kinetically using conventional Particle-In-Cell (PIC) techniques. The module can be used to describe either test particles motion in the fluid electromagnetic field or to solve the fully coupled MHD-PIC system of equations with particle backreaction on the fluid as originally introduced by \cite{Bai_etal.2015}. Particle backreaction on the fluid is included in the form of momentum-energy feedback and by introducing the CR-induced Hall term in Ohm's law. The hybrid MHD-PIC module can be employed to study CR kinetic effects on scales larger than the (ion) skin depth provided the Larmor gyration scale is properly resolved. When applicable, this formulation avoids to resolve microscopic scales offering a substantial computational saving with respect to PIC simulations. We present a fully-conservative formulation which is second-order accurate in time and space and extends to either Runge-Kutta (RK) or corner-transport-upwind (CTU) time-stepping schemes (for the fluid) while a standard Boris integrator is employed for the particles. For highly-energetic relativistic CRs and in order to overcome the time step restriction a novel sub-cycling strategy that retains second-order accuracy in time is presented. Numerical benchmarks and applications including Bell instability, diffusive shock acceleration and test particle acceleration in reconnecting layers are discussed.

Structural correlation of a nanoparticle-embedded mesoporous CoTiO3 perovskite for an efficient electrochemical supercapacitor

Abstract: We synthesized mesoporous cobalt titanate (CTO) microrods via the sol–gel method as an outstanding working electrode for the supercapacitor. The mesoporous CTO microrods were amassed in hexagonal shapes of an average width of ∼670 nm, and were composed of nanoparticles of average diameter ∼41 nm. The well crystalline CTO microrods of the hexagonal phase to the R space group possessed an average pore size distribution of 3.92 nm throughout the microrod. The mesoporous CTO microrods with increased textural boundaries played a vital role in the diffusion of ions, and they provided a specific capacitance of 608.4 F g−1 and a specific power of 4835.7 W kg−1 and a specific energy of 9.77 W h kg−1 in an aqueous 2 M KOH electrolyte, which was remarkably better than those of Ti, La, Cr, Fe, Ni, and Sr-based perovskites or their mixed heterostructures supplemented by metal oxides as an impurity. Furthermore, the diffusion-controlled access to the OH− ions (0.27 μs) deep inside the microrod conveyed high stability, a long life cycle for up to 1950 continuous charging–discharging cycles, and excellent capacitance retention of 82.3%. Overall, the mesoporous CTO shows its potential as an electrode for a long-cycle supercapacitor, and provides opportunities for additional enhancement after developing the core–shell hetero-architecture with other metal oxide materials such as MnO2, and TiO2.

Mid-rapidity anti-baryon to baryon ratios in pp collisions at √s =0.9, 2.76 and 7 TeV measured by ALICE

Abstract: The ratios of yields of anti-baryons to baryons probes the mechanisms of baryon-number transport. Results for (p) over bar /p, (Lambda) over bar/Lambda, (Xi) over bar (+)/(Xi) over bar (-) and (Omega) over bar (+)/(Omega) over bar (-) in pp collisions at root s = 0.9, 2.76 and 7 TeV, measured with the ALICE detector at the LHC, are reported. Within the experimental uncertainties and ranges covered by our measurement, these ratios are independent of rapidity, transverse momentum and multiplicity for all measured energies. The results are compared to expectations from event generators, such as PYTHIA and HIJING/B, that are used to model the particle production in pp collisions. The energy dependence of (p) over bar /p, (Lambda) over bar/(Lambda) over bar, (Xi) over bar (+)/(Xi) over bar (-) and (Omega) over bar (+)/(Omega) over bar (-), reaching values compatible with unity for root s = 7 TeV, complement the earlier (p) over bar /p measurement of ALICE. These dependencies can be described by exchanges with the Regge-trajectory intercept of alpha(J) approximate to 0.5, which are suppressed with increasing rapidity interval Delta y. Any significant contribution of an exchange not suppressed at large Delta y (reached at LHC energies) is disfavoured.

A robust, ultra low-power, data-dependent-power-supplied 11T SRAM cell with expanded read/write stabilities for internet-of-things applications

Abstract: With the increased requirement of on-chip data computations in internet of things based applications, the embedded on-chip SRAM memory has been under its renovation stage to overcome the classical problems like stability and poor energy efficiency. In this work, a data-dependent-power-supply mechanism for a new 11T SRAM cell is proposed with ultra-low leakage and improved read/write stability against the process–voltage–temperature variations. The proposed cell consumes static power in the fraction of picowatt range and has considerable enhancement in the value of write static noise margin (WSNM). In addition, the use of associated read decoupling approach, with the column-based read buffer, further improves the read stability of the proposed cell and make it comparable with the hold stability value. The percentage reduction in the leakage power of proposed 11T cell is $$99.97\%$$ , $$99.93\%$$ and $$99.97\%$$ , while the WSNM 1 is $$6.98\times$$ , $$3.12\times$$ and $$1.46\times$$ , and WSNM 0 is $$5.55\times$$ , $$1.25\times$$ and $$1.16\times$$ larger when operating at 0.4 V and compared to the conventional 6T and threshold voltage techniques based VTH_9T and data aware write assist (DAWA) 12T SRAM cell structures respectively. $$I_{read}{/}I_{leak}$$ ratio for the proposed cell has improved by $$6.55\times$$ , $$6.22\times$$ and $$5.11\times$$ when compared with the 6T, VTH_9T and DAWA12T SRAM to increase the memory density. Further, the post-layout Monte Carlo simulation results (2000 samples) confirm the robustness of the proposed cell against the process variations.