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Flexray is a high speed communication protocol designed for distributive control in automotive control applications. Control performance not only depends on the control algorithm but also on the scheduling constraints in communication. A balance between the control performance and communication constraints must required for the choice of the sampling rates of the control loops in a node. In this paper, an optimum sampling period of control loops to minimize the cost function, satisfying the scheduling constraints is obtained. An algorithm to obtain the delay in service of each task in a node of the control loop in the hyper period has been also developed. (C) 2015 The Authors. Published by Elsevier B.V.

It is widely known that Control Area Networks (CAN) are used in real-time, distributed and parallel processing which cover manufacture plants, humanoid robots, networking fields, etc., In applications where wireless conditions are encountered it is convenient to continue the exchange of CAN frames within the Wireless CAN (WCAN). The WCAN considered in this research is based on wireless token ring protocol (WTRP); a MAC protocol for wireless networks to reduce the number of retransmissions due to collision and the wired counterpart CAN attribute on message based communication. WCAN uses token frame method to provide channel access to the nodes in the system. This method allow all the nodes to share common broadcast channel by taken turns in transmitting upon receiving the token frame which is circulating within the network for specified amount of time. This method provides high throughput in bounded latency environment, consistent and predictable delays and good packet delivery ratio. The most important factor to consider when evaluating a control network is the end-to-end time delay between sensors, controllers, and actuators. The correct operation of a control system depends on the timeliness of the data coming over the network, and thus, a control network should be able to guarantee message delivery within a bounded transmission time. The proposed WCAN is modeled and simulated using QualNet, and its average end to end delay and packet delivery ratio (PDR) are calculated. The parameters boundaries of WCAN are evaluated to guarantee a maximum throughput and a minimum latency time, in the case of wireless communications, precisely WCAN.

In this article, we present an exact theoretical analysis of an $$M/M/1$$ M / M / 1 system, with arbitrary distribution of relative deadline for the end of service, operated under the first come first served scheduling policy with exact admission control. We provide an explicit solution to the functional equation that must be satisfied by the workload distribution, when the system reaches steady state. We use this solution to derive explicit expressions for the loss ratio and the sojourn time distribution. Finally, we compare this loss ratio with that of a similar system operating without admission control, in the cases of some common distributions of the relative deadline.

This paper considers a firm real-time M/M/1 system, where jobs have stochastic deadlines till the end of service. A method for approximately specifying the loss ratio of the earliest-deadline-first scheduling policy along with exit control through the early discarding technique is presented. This approximation uses the arrival rate and the mean relative deadline, normalized with respect to the mean service time, for exponential and uniform distributions of relative deadlines. Simulations show that the maximum approximation error is less than 4% and 2% for the two distributions, respectively, for a wide range of arrival rates and mean relative deadlines. (C) 2013 Elsevier B.V. All rights reserved.

This paper reviews the research work done on the response time analysis of messages in controller area network (CAN) from the time CAN specification was submitted for standardization (1990) and became a standard (1993) up to the present (2012). Such research includes the worst-case response time analysis which is deterministic and probabilistic response time analysis which is stochastic. A detailed view on both types of analyses is presented here. In addition to these analyses, there has been research on statistical analysis of controller area network message response times.

This paper reviews the research work done on the Reliability Analysis of Controller Area Network (CAN) based systems. During the last couple of decades, real-time researchers have extended schedulability analysis to a mature technique which for nontrivial systems can be used to determine whether a set of tasks executing on a single CPU or in a distributed system will meet their deadlines or not [1-3]. The main focus of the real-time research community is on hard real-time systems, and the essence of analyzing such systems is to investigate if deadlines are met in a worst case scenario. Whether this worst case actually will occur during execution, or if it is likely to occur, is not normally considered. Reliability modeling, on the other hand, involves study of fault models, characterization of distribution functions of faults and development of methods and tools for composing these distributions and models in estimating an overall reliability figure for the system [4]. This paper presents the research work done on reliability analysis developed with a focus on Controller-Area-Network-based automotive systems.

This paper reviews the research work done on the Modeling and Analysis of Wireless Controller Area Network (WCAN). The controller area network (CAN) has been long regarded as the pioneer in standardizing vehicle bus standard. Its influence has even been reached out to various applications in industrial automation; which includes military, aviation, electronics and many others. With wireless technology becoming more pervasive, there is also a need for CAN too to migrate and evolve to its wireless counterpart [1]. A few methods were proposed in the last decade [2-6] that utilized the advantageous of CAN into a wireless network system called wireless controller area network (WCAN). This paper reviews these approaches of WCAN.

The article by Anhang and Coffman entitled “The Great Reference Debate” (American Libraries, March 2002) is a challenge for reference librarians in all types of libraries. Three community college reference librarians respond to the issues raised in “The Great Reference Debate” and address the fundamental question, “Are reference librarians toast?”

Fire and gas safety FGS system are important tools for safeguarding process plants and production facilities that handle flammable and toxic materials. In general, a conventional fire and gas system has several shortcomings, such as weakness to noise and false alarms. In order to overcome these shortcomings, controller area network CAN-based FGS system has been implemented in our previous work. Further, considering that FGS systems are employed in hazardous environments, where wireless implementation of CAN is desirous, an attempt to make CAN wireless is carried out for these systems in this work, by using the radio protocol IEEE 802.15.4 to communicate CAN messages wireless. This work is a continuation of our previous work. Here the wired CAN interface is converted to wireless CAN and response time analysis of the system is done using CANoe v7.6.

Library instruction need not be boring and tedious. Reference librarians have evolved effective methods of spicing up their bibliographic instruction sessions which can result in better retention for information and better relations between the library and its users.

Technology has brought changes to the life of the community college reference librarian. Not only has information gained a speed and immediacy that it did not have a decade ago but library users have expectations of convenience when using CD-ROMs and other electronic information sources that have caused reference librarians to rethink some of their traditional service modes. Compared to the speed at which information may be accessed today, the older systems of the 1970s and 1980s do appear to be ‘antiques.’

This paper analyzes a new multiprocessor interconnection network — the folded cube-connected cycles (FCCC). This topology is obtained by replacing each node of an n -dimensional folded hypercube by an ( n + 1)-cycle. The FCCC n is a regular network of degree 3 and has ( n + 1)2 n nodes. We analyze the topological properties of the FCCC and compare them with those of the cube-connected cycles (CCC). The FCCC has a lower diameter and average distance than that of the CCC. In terms of the most commonly used cost metric (node degree x diameter), the FCCC is better than any of the hypercube-variant networks. It is strongly resilient, and has a fault diameter less than that of the CCC. In terms of bisection width and connectivity also, the FCCC is better than that of the CCC. We propose algorithms for one-to-one communication and broadcasting in FCCC. We also propose an optimal VLSI layout.

Micromobility protocols have been proposed to provide seamless local mobility support. There are several micro mobility protocols such as HMIP, Cellular IP and HAWAII. This paper focuses on the performance of single stream forwarding scheme of HAWAII . An analytical model is developed for the evaluation. The aim of the paper is to investigate the impact of the buffering at the old base station on the handoff and to introduce a buffer at the cross over router to eliminate the packet loss at the mobile host for a given play out delay and also show by means of simulation the packet loss at the mobile host dependent on the router service rates and link propagation delays.

In earlier work, nonisomorphic graphs have been converted into networks to realize Multistage Interconnection networks, which are topologically nonequivalent to the Baseline network. The drawback of this technique is that these nonequivalent networks are not guaranteed to be self-routing, because each node in the graph model can be replaced by a (2 × 2) switch in any one of the four different configurations. Hence, the problem of routing in these networks remains unsolved. Moreover, nonisomorphic graphs were obtained by interconnecting bipartite loops in a heuristic manner; the heuristic nature of this procedure makes it difficult to guarantee full connectivity in large networks. We solve these problems through a direct approach, in which a matrix model for self-routing networks is developed. An example is given to show that this model encompases nonequivalent self-routing networks. This approach has the additional advantage in that the matrix model itself ensures full connectivity.

In this paper, we develop a tool for carrying out acceptance tests in a multiprocessor system, for workloads that include both sporadic hard tasks with specified resource requirements, and multimedia tasks with firm (m, k) guarantees. The tool is a two-level scheduler. The higher-level server planner generates server arrangements for the multimedia server, such that it can meet the (m, k) firm guarantees, and can execute optional task instances as well, while the lower-level feasibility checker determines the schedulability of the sporadic tasks under the specified server arrangement. The two levels iterate until schedulability is determined. The tool has been validated through simulation.

This paper presents a usage-based transmission cost allocation method based on a new set of line utility factors (LUFs), which provides power transaction impact on each element of the network in deregulated power system operation. The developed LUFs relates the line flows with generation/load for a given network configuration. In this paper, a bilateral transaction contract model through a transaction matrix and line utility factors are used to evaluate cost of bilateral power contracts. The proposed method allocates the transaction costs over the participants/contracts proportional to the ratio of power flow caused by each participant/contract and the total power flows on a designated transmission line. The method has been applied on a few sample systems, and the results for sample systems and a real life EHV equivalent system are presented for illustrative purposes.

In a faulty torus/mesh, finding the maximal fault-free submesh is the main problem of reconfiguration. Chen and Hu [1] proposed a distributed method to determine the maximal fault-free submesh in a faulty torus. In this paper, we show that it is sufficient to apply the distributed algorithm proposed by Chen and Hu [1] to only few nodes of a torus. The time for determination of the maximal fault free submesh/submeshes (MFSS) is considerably reduced, by reduction in the number of messages needed for determination of MFSS. In addition, it also reduces the congestion in the network. We present an algorithm to determine the smallest submesh containing all faulty nodes in a torus. The proposed algorithm has a time complexity of O(n(m+k)) for a k-ary n-cube with m faults. Intensive simulation study reveals that number of messages is significantly reduced compared to Chen and Hu’s [1] method.

A new class of nets, called S-nets, is introduced for the performance analysis of scheduling algorithms used in real-time systems Deterministic timed Petri nets do not adequately model the scheduling of resources encountered in real-time systems, and need to be augmented with resource places and signal places, and a scheduler block, to facilitate the modeling of scheduling algorithms. The tokens are colored, and the transition firing rules are suitably modified. Further, the concept of transition folding is used, to get intuitively simple models of multiframe real-time systems. Two generic performance measures, called i?½load indexi?½ and i?½balance index,i?½ which characterize the resource utilization and the uniformity of workload distribution, respectively, are defined. The utility of S-nets for evaluating heuristic-based scheduling schemes is illustrated by considering three heuristics for real-time scheduling. S-nets are useful in tuning the hardware configuration and the underlying scheduling policy, so that the system utilization is maximized, and the workload distribution among the computing resources is balanced.

This paper presents VLSI/WSI designs for a recently introduced parallel architecture known as the folded cube-connected cycles (FCCC). We first discuss two layouts for the FCCC, in which there is no component redundancy. Then we incorporate redundancy and present locally and globally reconfigurable FCCCs. We also discuss the design of universal building blocks for the construction of fault-tolerant FCCCs of various dimensions.

The method of diakoptics is applied to the transient stability analysis of a power system. Diakoptics is used to obtain the transmission line power flows that are required in the step-by-step method. Through this approach, the stability studies of large power systems could be studied.