Pfair scheduling of generalized pinwheel task systems

[[abstract]]The scheduling of generalized pinwheel task systems is considered. It is shown that pinwheel scheduling is closely related to the fair scheduling of periodic task systems. This relationship is exploited to obtain new scheduling algorithms for generalized pinwheel task systems. When compared to traditional pinwheel scheduling algorithms, these new algorithms are both more efficient from a run-time complexity point of view, and have a higher density threshold, on a very large subclass of generalized pinwheel task systems.

Dietary Phytase: an ideal approach for a cost effective and low-polluting aquafeed

Global fishmeal production from wild-catch sources cannot continue to increase indefinitely; suitable alternatives have to be found for sustainable aquaculture. Plant-based aquafeed seems to be the ideal alternative to this, but has its own limitations. Plant ingredients are rich in phytic acid, which reduces the bioavailability of nutrients like minerals and protein to the fish, thereby causing aquaculture pollution. Dietary phytase treatment reduces the aquaculture pollution by improving the bioavailability of nutrients, and reduces the feed cost as evident from poultry and piggery. Phytase activity is highly dependent upon the pH of the gut. Unlike mammals, fish are either gastric or agastric, and hence, the action of dietary phytase varies from species to species. In this article, the authors attempt to summarise various effects of phytase on nutrient utilization, growth of fish and aquatic pollution

ILP-based approaches to partitioning recurrent workloads upon heterogeneous multiprocessors

The problem of partitioning systems of independent constrained-deadline sporadic tasks upon heterogeneous multiprocessor platforms is considered. Several different integer linear program (ILP) formulations of this problem, offering different tradeoffs between effectiveness (as quantified by speedup bound) and running time efficiency, are presented

EXTENSION OF THE FUZZY C MEANS CLUSTERING ALGORITHM TO FIT WITH THE COMPOSITE GRAPH MODEL FOR WEB DOCUMENT REPRESENTATION

Clustering techniques are mostly unsupervised methods that can be used to organize data into groups based on similarities among the individual data items. Fuzzy c-means (FCM) clustering is one of well known unsupervised clustering techniques, which can also be used for unsupervised web document clustering. In this chapter we will introduce a modified method of clustering where the data to be clustered will be represented by graphs instead of vectors or other models. Specifically, we will extend the classical FCM clustering algorithm to work with graphs that represent web documents (Phukon, K. K. (2012), Zadeh, L. A. (1965). Dunn, J. C.(1974)). We wish to use graphs because they can allow us to retain information which is often discarded in simpler models

First-principle density-functional calculation of the Raman spectra of BEDT-TTF

We present a first-principles density-functional calculation for the Raman spectra of a neutral BEDT-TTF molecule. Our results are in excellent agreement with experimental results. We show that a planar structure is not a stable state of a neutral BEDT-TTF molecule. We consider three possible conformations and discuss their relation to disorder in these systems.Comment: 3 pages, 2 figures, submitted to the proceedings of ISCOM 200

Mixed-Criticality Job Models: A Comparison

The Vestal model in widely used in the real-time scheduling community for representing mixed-criticality real-time workloads. This model requires that multiple WCET estimates -- one for each criticality level in a system -- be obtained for each task. Burns suggests that being required to obtain too many WCET estimates may place an undue burden on system developers, and proposes a simplification to the Vestal model that makes do with just two WCET estimates per task. Burns makes a convincing case in favor of adopting this simplified model; here, we report on our attempts at comparing the two models -- Vestal’s original model, and Burns’ simplification – with regards to expressiveness, as well as schedulability and the tractability of determining schedulability

The Parallel Supply Function Abstraction for a Virtual Multiprocessor

A new abstraction --- the Parallel Supply Function (PSF) --- is proposed for representing the computing capabilities offered by virtual platforms implemented atop identical multiprocessors. It is shown that this abstraction is strictly more powerful than previously-proposed ones, from the perspective of more accurately representing the inherent parallelism of the provided computing capabilities. Sufficient tests are derived for determining whether a given real-time task system, represented as a collection of sporadic tasks, is guaranteed to always meet all deadlines when scheduled upon a specified virtual platform using the global EDF scheduling algorithm

10071 Abstracts Collection -- Scheduling

From 14.02. to 19.02.2010, the Dagstuhl Seminar 10071 ``Scheduling \u27\u27 was held in Schloss Dagstuhl-Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available