Rate Monotonic with Minimum Release Time First for Scheduling Periodic Tasks in Embedded System

2014 ◽

Vol 2014 ◽

pp. 1-11

Author(s):

S. Ewins Pon Pushpa ◽

Manamalli Devasigamani

Keyword(s):

Release Time ◽

Periodic Tasks ◽

Task Set ◽

Processor Utilization ◽

Window Analysis ◽

Rate Monotonic ◽

Utilization Bound ◽

Priority Scheme ◽

Schedulability Test ◽

Necessary And Sufficient

The key for adopting the utilization-based schedulability test is to derive the utilization bound. Given the computation times, this paper proposes two utilization bound algorithms to derive interrelease times for nonpreemptive periodic tasks, using a new priority scheme, “Rate Monotonic Algorithm-Shortest Job First.” The obtained task set possesses the advantage of Rate Monotonic Algorithm and Shortest Job First priority scheme. Further, the task set is tested for schedulability, by first deriving a general schedulability condition from “problem window” analysis and, a necessary and sufficient schedulability condition for a task to be scheduled, at any release time are also derived. As a technical contribution, success ratio and effective processor utilization are analyzed for our proposed utilization bound algorithms on a uniprocessor architecture modeled using UML-RT.

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A modified rate-monotonic algorithm for scheduling periodic tasks with different importance in embedded system

2009 9th International Conference on Electronic Measurement & Instruments ◽

10.1109/icemi.2009.5274659 ◽

2009 ◽

Cited By ~ 1

Author(s):

Jiwen Dong ◽

Yang Zhang

Keyword(s):

Embedded System ◽

Periodic Tasks ◽

Rate Monotonic

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Ensuring the sustainability of real-time embedded system under both QoS and Energy Constraints

MATEC Web of Conferences ◽

10.1051/matecconf/201928104006 ◽

2019 ◽

Vol 281 ◽

pp. 04006

Author(s):

Maissa Abdallah ◽

Nadine Abdallah ◽

Maryline Chetto

Keyword(s):

Sensor Networks ◽

Embedded System ◽

Sensor Nodes ◽

Electronic Systems ◽

Periodic Tasks ◽

Energy Aware ◽

Power Sources ◽

Energy Harvesters ◽

Aperiodic Tasks ◽

Energy Constraints

Nowadays, wireless sensor networks (WSNs) are more and more used in applications such as environment monitoring, healthcare monitoring, etc...The challenge in sensor networks is to ensure the sustainability of the system by guaranteeing the required performance level. However, with the limited capacity of finite power sources and the need of guaranteeing a long lifetime of those systems, it is suitable to use energy harvesting which allows to supply low-power electronic systems by converting ambient energy into electric power. Hence, our study is concerned with the problem of soft periodic and aperiodic tasks scheduling in sensor nodes powered by energy harvesters. In this paper, we address this issue by proposing three energy-aware schedulers, namely BG-Green-RTO, BG-Green-BWP and Green-AWP which aim to improve the responsiveness of aperiodic tasks while still guaranteeing the execution of periodic tasks considering their timing and energy constraints. Such algorithms allow to gracefully cope with processing overload and energy starvation. Moreover, a simulation study permits to show their performance.

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Job-shop Scheduling Over a Heterogeneous Platform

International Journal of Computers Communications & Control ◽

10.15837/ijccc.2021.3.4221 ◽

2021 ◽

Vol 16 (3) ◽

Author(s):

Hector Benitez-Perez ◽

Jose A. Hermosillo-Gomez

Keyword(s):

Embedded System ◽

Manufacturing Systems ◽

Production Efficiency ◽

Job Shop ◽

Job Shop Scheduling ◽

Human Interaction ◽

Periodic Tasks ◽

Real Time Scheduling ◽

Shop Scheduling ◽

Heterogeneous Platform

Real-time scheduling involves determining the allocation of platform resources in such a way tasks can meet their temporal restrictions. This work focuses on job-shop tasks model in which a task have a finite number of nonpreemptive different instances (jobs) that share a unique hard deadline and their time requirements are known until task arrival. Non-preemptive scheduling is considered because this characteristic is widely used in industry. Besides job-shop scheduling has direct impacts on the production efficiency and costs of manufacturing systems. So that the development of analysis for tasks with these characteristics is necessary. The aim of this work is to propose an online scheduling test able to guarantee the execution of a new arriving task, which is generated by human interaction with an embedded system, otherwise to discart it. An extension of the schedulability test proposed by Baruah in 2006 for non-preemptive periodic tasks over an identical platform is presented in this paper. Such extension is applied to non-preemptive tasks that have hard deadlines over a heterogeneous platform. To do that, some virtual changes over both the task set and the platform are effectuated.

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Scheduling of Periodic Tasks with Data Dependency on Multiprocessors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.2131 ◽

2013 ◽

Vol 756-759 ◽

pp. 2131-2136

Author(s):

Jin Lin Wang

Keyword(s):

Time Constraints ◽

Release Time ◽

Data Dependency ◽

Scheduling Problem ◽

Periodic Tasks ◽

Dataflow Graphs ◽

Time Limits ◽

Static Schedule ◽

Data Constraints ◽

Synchronous Dataflow Graphs

This article studies the scheduling problem of a set of tasks with time or data constraints on a number of identical processors with full connections. We present an algorithm, in which a set of static schedule lists can be obtained, each for a processor, such that each task starts executing after its release time and completes its computation before its deadline, and all the precedence relations between tasks resulting from data dependency are satisfied. The data dependency relations between tasks are represented by Synchronous Dataflow Graphs (SDF) as they can indicate tasks concurrency and enable effective scheduling on multiprocessor platforms. The SDF, however, does not support the time constraints of tasks directly, thus an adaption is applied to conform to the time limits. With this adaption, the periodic tasks of implicit-deadline or constrained-deadline can be scheduled on multiprocessor platform effectively.

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Effect of coating method on release of Glimepiride from porosity osmotic pump tablets (POPTs)

Al Mustansiriyah Journal of Pharmaceutical Sciences ◽

10.32947/ajps.20.02.0448 ◽

2020 ◽

pp. 37-45

Keyword(s):

In Vitro Release ◽

Osmotic Pump ◽

Release Time ◽

Once Daily ◽

Coating Solution ◽

Continuous Release ◽

Red Color ◽

Coating Method ◽

Osmotic Agent

In this study, once-daily porosity osmotic pump tablets (POPTs) of Glimepiride were prepared using HPMC K100M (61%), osmotic agent (30% NaCl) coated using two different coating techniques spraying and dipping methods. The coating solution composed of ethyl cellulose (7.5%) w\w in ethanol (90%), castor oil (2%) as water-insoluble plasticizer and Gingo red color (0.5% w\w). In both techniques, the coating level was adjusted to give a 10% increase in the weight of the tablets. The effect of the coating by dipping technique with an increase in the weight of tablet (10 %, 20% & 50%) was also investigated to see the effect coating level on the percentage of drug release from POPTs. The results of the in vitro release of Glimepiride from tablets coated by the spraying method showed longer release time (24 hrs) than those coated with dipping method. On the other hand, increasing the coating level by dipping method retarded the release of the drug from tablets. However, the same retardation effect on release as shown with the spraying technique was only obtained by increasing the coating level with a 50% increase in the weight of the tablet. Thus, coating by spraying is more efficient to prepare POPTs to give a continuous release of Glimepiride from once daily table with the lowest increase in the total weight of the tablet.

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