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The main purpose of the paper is timing analysis of mixed critical applications on the multicore system to identify an efficient task scheduling mechanism to achieve three main objectives improving schedulability, achieving reliability and minimizing the number of cores used. The rise in transient faults in embedded systems due to the use of low-cost processors has led to the use of fault-tolerant scheduling and mapping techniques.

The paper opted for a simulation-based study. The simulation of mixed critical applications, like air traffic control systems and synthetic workloads, is carried out using a litmus-real time testbed on an Ubuntu machine. The heuristic algorithms for task allocation based on utilization factors and task criticalities are proposed for partitioned approaches with multiple objectives.

Both partitioned earliest deadline first (EDF) with the utilization-based heuristic and EDF-virtual deadline (VD) with a criticality-based heuristic for allocation works well, as it schedules the air traffic system with a 98% success ratio (SR) using only three processor cores with transient faults being handled by the active backup of the tasks. With synthetic task loads, the proposed criticality-based heuristic works well with EDF-VD, as the SR is 94%. The validation of the proposed heuristic is done with a global and partitioned approach of scheduling, considering active backups to make the system reliable. There is an improvement in SR by 11% as compared to the global approach and a 17% improvement in comparison with the partitioned fixed-priority approach with only three processor cores being used.

The simulations of mixed critical tasks are carried out on a real-time kernel based on Linux and are generalizable in Linux-based environments.

The rise in transient faults in embedded systems due to the use of low-cost processors has led to the use of fault-tolerant scheduling and mapping techniques.

This paper fulfills an identified need to have multi-objective task scheduling in a mixed critical system. The timing analysis helps to identify performance risks and assess alternative architectures used to achieve reliability in terms of transient faults.

The purpose of this paper is to propose novel parallel computational techniques for the parallelization of explicit finite element generalized approximate inverse methods, based on Portable Operating System Interface for UniX (POSIX) threads, for multicore systems.

The authors' main motive for the derivation of the new Parallel Generalized Approximate Inverse Finite Element Matrix algorithmic techniques is that they can be efficiently used in conjunction with explicit preconditioned conjugate gradient‐type schemes on multicore systems. The proposed parallelization technique of the Optimized Banded Generalized Approximate Inverse Finite Element Matrix (OBGAIFEM) algorithm is achieved based on the concept of the “fish bone” approach with the use of a thread pool pattern. Theoretical estimates on the computational complexity of the parallel generalized approximate inverse finite element matrix algorithmic techniques are also derived.

Application of the proposed method on a two‐dimensional boundary value problem is discussed and numerical results are given on a multicore system using POSIX threads. These results tend to become optimum and are favorably compared to corresponding results from multiprocessor systems, as presented in recent work by Gravvanis et al.

The proposed parallel explicit finite element generalized approximate inverse preconditioning, using approximate factorization and approximate inverse algorithms, is an efficient computational method that is valuable for computer scientists and for scientists and engineers in engineering computations.

This profile is somewhat more exotic than the usual ones found in this, hopefully, august journal and your reporter would like to dwell on the background more than is usual. If you take your world atlas, you may find Ipoh as an isolated dot in the middle of the Malaysian peninsula, a little to the north‐west of Kuala Lumpur. Viewed thus, why would Multicore Solders choose such an isolated outpost to establish a subsidiary factory? Arriving at the international airport at Kuala Lumpur starts to give one a clue: there are enormous bare scars in the plain. Flying from Kuala Lumpur to Ipoh, these scars multiply. They are the remains of the open‐cast tin mines in the alluvial deposits. Viewed from the air, they are a terrible blot on the landscape. The amazing thing is that they juxtapose oil palm, fruit and rubber plantations and even untouched jungle, but they remain bare and desert for decades. It is evident that no effort has been made to conserve the vegetable soil and replace it after the mining operations are finished, but this may be because the humus layer is so thin that it would be impossible to do so. To the ignorant European that this writer is, I imagined that the jungle was an all‐invading vegetation ready to swallow‐up every square metre of land: not so, it is a very precarious ecosystem where the humus formed by the rotting vegetation is swallowed up by the new growth faster than it can form. The jungle soil is very thin, bare rock being common and such a humus layer may take decades or even centuries to form. Most of the disused tin‐mines are therefore as devoid of life as the starkest desert. It would seem that, after fifty years or so, the first signs of vegetation start to reappear, a very meagre growth which, in time, may develop into scrub or secondary jungle without high trees.