Abstract
Wireless networks play an increasingly important role in application areas such as factory-floor automation, process control, and automotive electronics. In this paper, we address the problem of sharing a wireless channel among a set of sporadic message streams where a message stream issues transmission requests with real-time deadlines. For this problem, we propose a collision-free wireless medium access control (MAC) protocol, which implements static-priority scheduling and supports a large number of priority levels. The MAC protocol allows multiple masters and is fully distributed; it is an adaptation to a wireless channel of the dominance protocol used in the CAN bus, a proven communication technology for various industrial applications. However, unlike that protocol, our protocol does not require a node having the ability to receive an incoming bit from the channel while transmitting to the channel. The evaluation of the protocol with real embedded computing platforms is presented to show that the proposed protocol is in fact collision-free and prioritized. We measure the response times of our implementation and find that the response-time analysis developed for the protocol indeed offers an upper bound on the response times.

Abstract
Consider a communication medium shared among a set of computer nodes;. these computer nodes issue messages that are requested to be transmitted and they must finish their transmission before their respective deadlines. TDMA/SS is, a protocol that solves this problem; it is a specific type of Time Division Multiple Access (TDMA) where. a computer node is allowed to skip its time slot and then this time slot can be used by another computer node.. We present an algorithm that computes exact queuing times for TDMA/SS in conjunction with Rate-Monotonic (RM) or Earliest-Deadline-First (EDF).

Abstract
Consider the problem of deciding whether a set of n sporadic message streams meet deadlines on a Controller Area Network (CAN) bits for a specified priority assignment. It is assumed that message streams have implicit deadlines and no release jitter. An algorithm to solve this problem is well known but unfortunately it time complexity is non-polynomial. We present an algorithm with polynomial time-complexity for computing an tipper bound on the response times. Clearly, if the tipper bound on the response time does not exceed the deadline then all deadlines are met. The pessimism of our approach is proven: if the upper bound of the response time exceeds the deadline then the response time exceeds the deadline as well for a CAN network with half the speed.

Abstract

Abstract
In this paper we analyse and evaluate several Scheduling Algorithms that are candidates to support Quality of Service and Service Integration in Sensor and Actuator Networks. They should satisfy two main goals: to guarantee committed delays for time sensitive services, and to improve the network transmission efficiency. The algorithms are described and some results, obtained by simulation, are presented. The proposed Traffic Class Oriented Algorithm proved to be a good solution to meet the proposed objectives as well as to integrate traffic generated by Fieldbus devices and control applications in real communication networks.

Abstract
A fiber-sensing scheme with controlled sensitivity comprising a fiber Bragg grating (FBG) and a mechanically induced long-period fiber grating (MLPFG) is presented. The FBG was written by exposing the fiber to 248-nm UV laser radiation such that the Bragg wavelength is localized on the slope of a resonant band of a mechanical grating, which was produced by winding a nylon string around a fiber/grooved tube set. The strength of that resonant band was altered by applying loads to the MLPFG. For different loads, the FBG was submitted to strain values of up to 2200 mu epsilon, in steps of 200 mu epsilon, during which the Bragg wavelength and the respective transmitted peak power through the MLPFG were recorded. It was demonstrated that by applying a weight with a value of 0.78 kg to the MLPFG, the sensitivity of the FBG interrogation technique to strain variations increased from 2.23 (without load) to 3.20 pW/mu epsilon.