The earliest-pseudo-deadline-first (EPDF) Pfair algorithm is more efficient than other known Pfair scheduling algorithms, but is not optimal for scheduling recurrent real-time task systems on more than two identical processors. Although not optimal, EPDF may be preferable for real-time systems instantiated on less-powerful platforms, those with soft timing constraints, or those whose task composition can change at run-time. In prior work, Srinivasan and Anderson established a sufficient per-task utilization restriction for ensuring a tardiness of at most q quanta, where q ≥ 1, under EPDF. They also conjectured that under this algorithm, a tardiness bound of one quantum applies to task systems that are not subject to any restriction other than the obvious restrictions, namely, that the total system utilization not exceed the available processing capacity and per-task utilizations not exceed 1.0. In this paper, we present counterexamples that show that their conjecture is false and present sufficient per-task utilization restrictions that are more liberal than theirs. For ensuring a tardiness bound of one quantum, our restriction presents an improvement of 50% over the previous one.

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-Substanti al investments in infrastructure worl d over and rapi d advancement in construction technolog y has created acute shortage of skilled workers. The skill deficiency gets aggravated further due to absenteeism, migration, etc. In practice, i t was observed that there exist several parti ally trained semi-skilled workers having expertise in one or more trade. Using these semi-skilled workers as substitute can address the shortage of skilled workers to some extent. On the contrary, skilled workers alone are considered while pl anning and scheduling in most of the construction projects. Here, the potenti al capability of these parti ally trained workers remains unexploited because of their default groupi ng with unskilled workers.The root cause of this skill treatment can be the absence of standardised system of screening and classification of workers into di fferent skill category as highly skilled, skilled, semi -skilled, or unskilled and the ambiguity in updating or maintaining the worker's database. Hence, the objecti ve of the present study is to review the "skill" levels and the worker's skill utilization to the maxi mum extent possible. To achieve this, a framework has been proposed to generate worker's multi skill database (WMSD) and dynamic scheduling to address the uncertainty caused by deficit of skilled workers.

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