The Controller Area Network (CAN) is one of the most popular networks for industrial distributed embeddedsystems, particularly automotive systems. In these systems the timely transmission of data messages is a key re...
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The Controller Area Network (CAN) is one of the most popular networks for industrial distributed embeddedsystems, particularly automotive systems. In these systems the timely transmission of data messages is a key requirement. In this paper, a physical testbed is presented that allows the evaluation of the timing behavior of CAN message transmissions. The use of FPGAs as processing nodes allows to accurately perform measurements without influencing the original system due to the inherent parallelism of programmable hardware. As a case study, the improvement of response times by using dynamic scheduling of messages is shown with the testbed. Furthermore, the testbed helps to identify time critical simulation parameters.
Software architectures of large-scale systems are perceptibly shifting towards employing open and distributed computing. Service Oriented Computing (SOC) is a typical example of such environment in which the quality o...
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Software architectures of large-scale systems are perceptibly shifting towards employing open and distributed computing. Service Oriented Computing (SOC) is a typical example of such environment in which the quality of interactions amongst software agents is a critical concern. Agent-based web services in open and distributed architectures need to interact with each other to achieve their goals and fulfill complex user requests. Two common tasks are influenced by the quality of interactions among web services: the selection and composition. Thus, to ensure the maximum gain in both tasks, it is essential for each agent-based web service to maintain a model of its environment. This model then provides a means for a web service to predict the quality of future interactions with its peers. In this paper, we formulate this model as a machine learning problem which we analyze by modeling the trustworthiness of web services using probabilistic models. We propose two approaches for trust learning of single and composed services; Bayesian Networks and Mixture of Multinomial Dirichlet Distributions (MMDD). The effectiveness of our approaches is empirically assessed using a simulation study. Our results show that representing the quality of a web service by Multinomial Dirichlet Distribution (MDD) provides high flexibility and accuracy in modeling trust. They also show that using our approaches to estimate trust enhances web services selection and composition.
System-level design space exploration (DSE), which is performed early in the design process, is of eminent importance to the design of complex multi-processor embedded system architectures. During system-level DSE, sy...
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ISBN:
(纸本)9783981080186
System-level design space exploration (DSE), which is performed early in the design process, is of eminent importance to the design of complex multi-processor embedded system architectures. During system-level DSE, system parameters like, e.g., the number and type of processors, the type and size of memories, or the mapping of application tasks to architectural resources, are considered. simulation-based DSE, in which different design instances are evaluated using system-level simulations, typically are computationally costly. Even using high-level simulations and efficient exploration algorithms, the simulation time to evaluate design points forms a real bottleneck in such DSE. Therefore, the vast design space that needs to be searched requires effective design space pruning techniques. This paper presents a technique to reduce the number of simulations needed during system-level DSE. More specifically, we propose an iterative design space pruning methodology based on static throughput analysis of different application mappings. By interleaving these analytical throughput estimations with simulations, our hybrid approach can significantly reduce the number of simulations that are needed during the process of DSE.
Resistive Random Access Memories (ReRAMs) fabricated in the back-end-of-line are a promising breakthrough for including permanent retention mechanisms in embeddedsystems. This low-cost solution opens the way to advan...
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Resistive Random Access Memories (ReRAMs) fabricated in the back-end-of-line are a promising breakthrough for including permanent retention mechanisms in embeddedsystems. This low-cost solution opens the way to advanced power management schemes. In this paper, we propose novel design architecture of a non-volatile flip-flop based on Bipolar ReRAMs (Bi-RNVFF). Compared to state-of-the-art Data-Retention flip-flop (with Balloon latch), the proposed design is 25% smaller due to 6T structure compared to the 8T structure of Data-Retention flip-flop. Moreover, being non-volatile, the proposed architecture exhibits a zero leakage compared to a Data-Retention Flip-Flop, which consumes ~3.2μW in sleep mode (leakage) for a 10K Flip-Flop design implemented in 22nm FDSOI technology. Our simulation results show that Bi-RNVFF is a true alternative for future “Power-on, Power-off” application adding Non-Volatility without significant burdening of the existing architectures.
Todate it has been shown that reconfigurable manufacturing systems (RMSs) have advantages over other production systems in dynamic manufacturing environments. However, the operations of RMSs are complex and hence requ...
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Todate it has been shown that reconfigurable manufacturing systems (RMSs) have advantages over other production systems in dynamic manufacturing environments. However, the operations of RMSs are complex and hence require unique manufacturing support systems. In this paper, we examine the process planning function for RMSs in an attempt to develop a process planning function that is suitable for operating RMSs. We explore the propects of a process planning function that embeddes strongly related scheduling sub-functions in order to avoid sub-optimal operating performance. The uniqueness of this approach lies in optimizing process plans for RMSs in a bid to exploit the potential of production flexibility and reconfigurability in dynamic manufacturing environments. A simulated annealing algorithm is developed and tasked to provide solutions to the proposed process planning model. Evaluation of the obtained process plans indicates that they retain routing and processing flexibility which allows for logical reconfiguration of the manufacturing system.
Information and Communications Technology is increasingly becoming a part of our daily activities. Nowadays, we are able to sense a broad range of entities in the world: from physical entities that comprise the Intern...
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ISBN:
(纸本)9781450316286
Information and Communications Technology is increasingly becoming a part of our daily activities. Nowadays, we are able to sense a broad range of entities in the world: from physical entities that comprise the Internet of Things (IoT) to social entities that include people in social networks. We can expect, to have a ubiquitous sensing infrastructure in different environments, with varying needs and complexities. While these sensors/entities are mostly static, smart phones are taking center stage as the most widely adopted and ubiquitous computing device. Smart phones have enormous potential for the study of human social networks and human behavior "in vivo," in a natural context outside laboratories. Besides their computing power, smart phones are currently available with an increasing rich set of embedded sensors, such as GPS, accelerometer, microphone, camera, gyroscope and digital compass. Sensing vast areas becomes more feasible when people carrying their portable devices collect data and collaborate among themselves. systems that enable sensed data in this way are named participatory sensing systems (PSSs). In those networks, the shared data is not limited to sensor readings passively generated by the device, but also includes proactive user observations. A challenge is how to obtain meaningful information from this large amount of data at different scales along the time. Some of the traditional techniques that have been used to process those distinct data sources are information fusion, data mining and machine learning. Notice that the consumers of such information can be, in one extreme, a large set of cooperating or non-cooperating entities, and, in the other, an individual or a "thing", for instance. Two important attributes of the sensed data are the location and time where they are collected. Localization and tracking play a key role in ubiquitous computing due to the fact that a wide variety of envisioned applications that collect sensed data rely on t
Many complex systems, such as multi-agent modeling and simulation which are crucial in military applications, necessitate concurrent task planning and decision making. These applications include battlefield modeling a...
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Many complex systems, such as multi-agent modeling and simulation which are crucial in military applications, necessitate concurrent task planning and decision making. These applications include battlefield modeling and simulation for soldier virtual training. In general these systems are implemented on automated systems with distributed architectures on heterogeneous operating systems and hardware platforms. In this paper we present an autonomous multi agent path planning system with agents-in-formation constraints in a distributed computing environment. Here a given agent, an entity with behaviors, exchanges sensory positioning feedback information over the network with other agents that are running on separate networked distributed computing nodes than the one the given agent is running on. Hence the agents do not have complete knowledge of the environment, but only a limited one. That is, in keeping with the agent formation constraint, the agents have knowledge only of the agents' information residing on the distributed memory of the computing node the agents are running on. The agents exchange agents' positioning sensory information of the rest of the agents they are interacting with, over a distributed network. Here agents autonomous trajectory planning is achieved for each agent to reach its destination via an unstructured distributed environment filled with dynamic obstacles and other agents. One focus is on the agents achieving their goals under real time formation constraints. We propose a multi-threaded architecture to achieve light-weight concurrency and multi-agent cooperative concurrency, as they allow separation between address space and thread control. Additionally, a threads-based architecture benefits from non-blocking system calls. Finally, experimental results are presented to show the potential of the proposed method for multi-agent distributed path planning.
WSN technology involves a set of challenges ranging from determining resource characteristics of the wireless network, when and how to optimise energy and how much processing to do in each node, to principles for mana...
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WSN technology involves a set of challenges ranging from determining resource characteristics of the wireless network, when and how to optimise energy and how much processing to do in each node, to principles for management of entire sensor networks and how the data produced by sensor networks can be managed, used and presented. A simulation environment seemed to be then essential, since the test of the hardware and software is hard and difficult. Beyond cost and time savings, the simulator offers the great opportunity to extend the potential and the features of WSN. As there are many simulators, we make an attempt in this paper to specify the important ones related to energy consumption. In fact, we discuss the performance, reliability and usefulness of each of them to better see the disadvantages of these simulators and their strong points to be able to develop a better model.
In this paper the basic concept and technical characteristics of airborne 3D digital earth are expounded at first, and then the functions and running mode are analyzed, and the organization and optimization strategies...
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ISBN:
(纸本)9781467308724
In this paper the basic concept and technical characteristics of airborne 3D digital earth are expounded at first, and then the functions and running mode are analyzed, and the organization and optimization strategies of multi-resolution global terrain and image models and aviation electronic map are studied in VxWorks. Furthermore, the author explores such key technologies as dynamic data scheduling, progressive graphics refreshing, rendering in real-time and map symbolization of each data tile in 3D scene, analysis and computing of ground proximity warning, aviation information displaying, etc. It has been proved that these technologies are very effective in the actual application of embedded 3D digital earth system and have broad prospects.
Miniature manipulators have a special role in applications that limited spaces exist. Some attractive applications are active catheters suitable tools in minimally invasive surgery and gripping and manipulating in sma...
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Miniature manipulators have a special role in applications that limited spaces exist. Some attractive applications are active catheters suitable tools in minimally invasive surgery and gripping and manipulating in small spaces. On the other hand, modular robotic systems are fast growing solutions for cases where the manipulator should be extended for different applications. The features of the applied module direct affect the overall property and performance of the developed system. The major application of SMA actuators is developing miniature systems. In this paper, first of all, a basic concept for developing a flexible module is introduced. In the presented work, by attaching the wire on a flexible beam, the small strain of the SMA actuator resulted in a larger deformation in the module. The module incorporates several Shape Memory Alloy (SMA) actuators to create relative deflection between two parallel plates connected to each other through a flexible beam. SMA actuators are embedded around the flexible beam to produce deflection in different directions after actuation. By connecting various modules in a serial manner, a manipulator could be developed. In the design process of manipulator, a mechatronics approach is considered. Through the design process, the dynamic modeling of the system is simulated in Simulink of Matlab. In this way, previously verified model of Brinson is used for SMAs model. The provided platform of simulation assists in optimizing the dimensions of the designed module. Finally, the specification of a module working properly is suggested for applying as a manipulator.
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