339,198 research outputs found
Prototyping and Performance Analysis of a QoS MAC Layer for Industrial Wireless Network
Today's industrial sensor networks require strong reliability and guarantees
on messages delivery. These needs are even more important in real time
applications like control/command, such as robotic wireless communications
where strong temporal constraints are critical. For these reasons, classical
random-based Medium Access Control (MAC) protocols present a non-null frame
collision probability. In this paper we present an original full deterministic
MAC-layer for industrial wireless network and its performance evaluation thanks
to the development of a material prototype.Comment: 7th IFAC International Conference on. Fieldbuses and nETworks in
industrial and embedded systems, Toulouse : France (2007
Conclusions from the European Roadmap on Control of Computing Systems
The use of control-based methods for resource management in real-time computing and communication systems has gained a substantial interest recently. Applications areas include performance control of web-servers, dynamic resource management in embedded systems, traffic control in communication networks, transaction management in database servers, error control in software systems, and autonomic computing. Within the European EU/IST FP6 Network of Exellence ARTIST2 on Embedded System Design a roadmap on Control of Real-Time Computing Systems has recently been completed. The focus of the roadmap is how flexibility, adaptivity, performance and robustness can be achieved in a real-time computing or communication system through the use of control theory. The item that is controlled is in most cases the allocation of computing and communication resources, e.g., the distribution or scheduling of CPU time among different competing tasks, jobs, requests, or transactions, or the communication resources in a network. Due to this, control of computing systems also goes under the name of feedback scheduling. The roadmap is divided into six research areas: control of server systems, control of CPU resources, control of communication networks, error control of software systems, feedback scheduling of control systems, and control middleware. For each area an overview is given and challenges for future research are stated. The aim of this position paper is to summarize the conclusions concerning these research challenges. In this paper, we will only cover the first four of the areas above. A preliminary version of the roadmap can be found on http://www.control.lth.se/user/karlerik/roadmap1.pd
Improving performance guarantees in wormhole mesh NoC designs
Wormhole-based mesh Networks-on-Chip (wNoC) are deployed in high-performance many-core processors due to their physical scalability and low-cost. Delivering tight and time composable Worst-Case Execution Time (WCET) estimates for applications as needed in safety-critical real-time embedded systems is challenged by wNoCs due to their distributed nature. We propose a bandwidth control mechanism for wNoCs that enables the computation of tight time-composable WCET estimates with low average performance degradation and high scalability. Our evaluation
with the EEMBC automotive suite and an industrial real-time parallel avionics application confirms so.The research leading to these results is funded by the European Union Seventh
Framework Programme under grant agreement no. 287519 (parMERASA)
and by the Ministry of Science and Technology of Spain under contract TIN2012-34557. Milos Panic is funded by the Spanish Ministry of Education under the FPU grant FPU12/05966. Carles Hernández is jointly funded by the
Spanish Ministry of Economy and Competitiveness and FEDER funds through
grant TIN2014-60404-JIN. Jaume Abella is partially supported by the Ministry
of Economy and Competitiveness under Ramon y Cajal postdoctoral fellowship
number RYC-2013-14717.Peer ReviewedPostprint (author's final draft
Real-Time Sensor Networks and Systems for the Industrial IoT
The Industrial Internet of Things (Industrial IoT—IIoT) has emerged as the core construct behind the various cyber-physical systems constituting a principal dimension of the fourth Industrial Revolution. While initially born as the concept behind specific industrial applications of generic IoT technologies, for the optimization of operational efficiency in automation and control, it quickly enabled the achievement of the total convergence of Operational (OT) and Information Technologies (IT). The IIoT has now surpassed the traditional borders of automation and control functions in the process and manufacturing industry, shifting towards a wider domain of functions and industries, embraced under the dominant global initiatives and architectural frameworks of Industry 4.0 (or Industrie 4.0) in Germany, Industrial Internet in the US, Society 5.0 in Japan, and Made-in-China 2025 in China. As real-time embedded systems are quickly achieving ubiquity in everyday life and in industrial environments, and many processes already depend on real-time cyber-physical systems and embedded sensors, the integration of IoT with cognitive computing and real-time data exchange is essential for real-time analytics and realization of digital twins in smart environments and services under the various frameworks’ provisions. In this context, real-time sensor networks and systems for the Industrial IoT encompass multiple technologies and raise significant design, optimization, integration and exploitation challenges. The ten articles in this Special Issue describe advances in real-time sensor networks and systems that are significant enablers of the Industrial IoT paradigm. In the relevant landscape, the domain of wireless networking technologies is centrally positioned, as expected
Spectral analysis of signals by time-domain statistical characterization and neural network processing: Application to correction of spectral amplitude alterations in pulse-like waveforms
We present a time-domain method to detect and correct spectral alterations of
signals by employing statistical characterization of waveforms and a
pattern-recognition procedure using simple Artificial Neural Networks. The
proposed strategy implements very-fast routines with a computational cost
proportional to the number of signal samples, being convenient for applications
in embedded environments with limited computational capabilities or fast
real-time control tasks. We use the proposed algorithms to correct spectral
amplitude attenuations in a pulse-like waveform with a sinc profile as an
application example
PROOF OF CONCEPT PROTOTYPE FOR A RAILROAD PEDESTRIAN WARNING SYSTEM USING WIRELESS SENSOR NETWORKS
Wireless sensor network is an emerging research topic due to its vast and ever-growing applications. Wireless sensor networks are made up of small nodes whose main goal is to monitor, compute and transmit data. The nodes are basically made up of low powered microcontrollers, wireless transceiver chips, sensors to monitor their environment and a power source. The applications of wireless sensor networks range from basic household applications, such as health monitoring, appliance control and security to military application, such as intruder detection.
The wide spread application of wireless sensor networks has brought to light many research issues such as battery efficiency, unreliable routing protocols due to node failures, localization issues and security vulnerabilities. This report will describe the hardware development of a fault tolerant routing protocol for railroad pedestrian warning system. The protocol implemented is a peer to peer multi-hop TDMA based protocol for nodes arranged in a linear zigzag chain arrangement. The basic working of the protocol was derived from Wireless Architecture for Hard Real-Time Embedded Networks (WAHREN)
A Real-Time Service-Oriented Architecture for Industrial Automation
Industrial automation platforms are experiencing a paradigm shift. New technologies are making their way in the area, including embedded real-time systems, standard local area networks like Ethernet, Wi-Fi and ZigBee, IP-based communication protocols, standard service oriented architectures (SOAs) and Web services. An automation system will be composed of flexible autonomous components with plug & play functionality, self configuration and diagnostics, and autonomic local control that communicate through standard networking technologies. However, the introduction of these new technologies raises important problems that need to be properly solved, one of these being the need to support real-time and quality-of-service (QoS) for real-time applications. This paper describes a SOA enhanced with real-time capabilities for industrial automation. The proposed architecture allows for negotiation of the QoS requested by clients from Web services, and provides temporal encapsulation of individual activities. This way, it is possible to perform an a priori analysis of the temporal behavior of each service, and to avoid unwanted interference among them. After describing the architecture, experimental results gathered on a real implementation of the framework (which leverages a soft real-time scheduler for the Linux kernel) are presented, showing the effectiveness of the proposed solution. The experiments were performed on simple case studies designed in the context of industrial automation applications
Advancing Urban Flood Resilience With Smart Water Infrastructure
Advances in wireless communications and low-power electronics are enabling a new generation of smart water systems that will employ real-time sensing and control to solve our most pressing water challenges. In a future characterized by these systems, networks of sensors will detect and communicate flood events at the neighborhood scale to improve disaster response. Meanwhile, wirelessly-controlled valves and pumps will coordinate reservoir releases to halt combined sewer overflows and restore water quality in urban streams. While these technologies promise to transform the field of water resources engineering, considerable knowledge gaps remain with regards to how smart water systems should be designed and operated. This dissertation presents foundational work towards building the smart water systems of the future, with a particular focus on applications to urban flooding. First, I introduce a first-of-its-kind embedded platform for real-time sensing and control of stormwater systems that will enable emergency managers to detect and respond to urban flood events in real-time. Next, I introduce new methods for hydrologic data assimilation that will enable real-time geolocation of floods and water quality hazards. Finally, I present theoretical contributions to the problem of controller placement in hydraulic networks that will help guide the design of future decentralized flood control systems. Taken together, these contributions pave the way for adaptive stormwater infrastructure that will mitigate the impacts of urban flooding through real-time response.PHDCivil EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163144/1/mdbartos_1.pd
VeriSparse: Training Verified Locally Robust Sparse Neural Networks from Scratch
Several safety-critical applications such as self-navigation, health care,
and industrial control systems use embedded systems as their core. Recent
advancements in Neural Networks (NNs) in approximating complex functions make
them well-suited for these domains. However, the compute-intensive nature of
NNs limits their deployment and training in embedded systems with limited
computation and storage capacities. Moreover, the adversarial vulnerability of
NNs challenges their use in safety-critical scenarios. Hence, developing sparse
models having robustness guarantees while leveraging fewer resources during
training is critical in expanding NNs' use in safety-critical and
resource-constrained embedding system settings. This paper presents
'VeriSparse'-- a framework to search verified locally robust sparse networks
starting from a random sparse initialization (i.e., scratch). VeriSparse
obtains sparse NNs exhibiting similar or higher verified local robustness,
requiring one-third of the training time compared to the state-of-the-art
approaches. Furthermore, VeriSparse performs both structured and unstructured
sparsification, enabling storage, computing-resource, and computation time
reduction during inference generation. Thus, it facilitates the
resource-constraint embedding platforms to leverage verified robust NN models,
expanding their scope to safety-critical, real-time, and edge applications. We
exhaustively investigated VeriSparse's efficacy and generalizability by
evaluating various benchmark and application-specific datasets across several
model architectures.Comment: 21 pages, 13 tables, 3 figure
Drift-Free Latent Space Representation for Soft Strain Sensors
Soft strain sensors are becoming increasingly popular for
obtaining tactile information in soft robotic applications.
Diverse technological solutions are being investigated to
design these sensors. Simultaneously, new methods for
modeling these sensor are being proposed due to their
highly nonlinear, time varying properties. Among them,
machine learning based approaches, particularly using
dynamic recurrent neural networks look the most promising.
However, these complex networks have large number of free
parameters to be tuned, making it difficult to apply them
for real-world applications. This paper introduces the
concept of transfer learning for modelling soft strain
sensors, which allows us to utilize information learned in
one task to be applied to another task. We demonstrate this
technique on a passive anthropomorphic finger with embedded
strain sensors used for two regression tasks. We show how
the transfer learning approach can drastically reduce the
number of free parameters to be tuned for learning new
skills. This work is an important step towards scaling of
sensor networks (algorithm-wise) and for using soft sensor
data for high-level control tasks
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