| 251. |
- Seceleanu, Tiberiu, et al.
(författare)
-
Communicating with Synchronized Environments
- 2006
-
Ingår i: Proceedings of the Sixth International Conference on Application of Concurrency to System Design. - 0769525563 - 9780769525563 ; , s. 15-24
-
Konferensbidrag (refereegranskat)abstract
- In the modern design environments, different modules, available in existent libraries, may obey different architectural styles and execution models. Reaching a well-behaved composition of such modules is a very important task of the system designer. In the framework of the action systems formalism, we analyze the co-existence of two models of execution, one synchronized, the other, interleaved. We devise a communication scheme, similar to the classical paradigm of polling, which allows us to model synchronized components that correctly exchange information, within the borders of a global system, with their non-synchronized partners. Derivations of such mechanisms follow specific correctness rules for refinement. We illustrate our methods on an audio system example, implementable as either a software or a hardware device.
|
|
| 252. |
- Seceleanu, Tiberiu, et al.
(författare)
-
Modeling Communication with Synchronized Environments
- 2008
-
Ingår i: Fundamenta Informaticae. - 0169-2968 .- 1875-8681. ; 86:3, s. 343-369
-
Tidskriftsartikel (refereegranskat)abstract
- A deterministic behavior of systems composed of several modules is a desirable design goal. Assembling a complex system from components requires also a high degree of re-usability. The compatibility of the selected components may become a problem even at abstract design levels, due to possible different degrees of model determinacy, possible different execution models, etc. In this cases, an overall deterministic system behavior is difficult to achieve. The development of communication mechanisms between such components will have then to accommodate the differences, so that both correct processing and information exchange (data and control, appropriate choices and relative timing or sequencing) are achieved. For instance, human-machine interaction offers a good example of cooperation between deterministic models (machines) communicating with highly non-deterministic counterparts (the human models, if not restricted). We analyze here such communication mechanisms by "confronting" synchronized and un-synchronized models of execution, in the framework of action systems, a state based formalism. We "force" the two models to coexist within the same context and explore the possibilities of building trustworthy communication channels between them. We base our approach on a combined polling - interrupt scheme, which allows us to mitigate communication issues that may otherwise compromise the correct input-output system behavior. More robust system models are obtained by applying specific correctness rules of refinement. We illustrate our methods on an audio system example, implementable as either a software or a hardware device.
|
|
| 253. |
|
|
| 254. |
- Seceleanu, Tiberiu, et al.
(författare)
-
On-Chip Distributed Architectures
- 2006
-
Ingår i: 2006 IEEE International Systems-on-Chip Conference, SOC. - : IEEE. - 0780397819 - 9780780397811 ; , s. 329-330
-
Konferensbidrag (refereegranskat)
|
|
| 255. |
- Shallari, Irida, et al.
(författare)
-
Design space exploration for an IoT node : Trade-offs in processing and communication
- 2021
-
Ingår i: IEEE Access. - 2169-3536. ; 9, s. 65078-65090
-
Tidskriftsartikel (refereegranskat)abstract
- Optimising the energy consumption of IoT nodes can be tedious due to the due to complex trade-offs involved between processing and communication. In this article, we investigate the partitioning of processing between the sensor node and a server and study the energy trade-offs involved. We propose a method that provides a trade-off analysis for a given set of constraints and allows for exploring several intelligence partitioning configurations. Furthermore, we demonstrate how this method can be used for the analysis of four design examples with traditional and CNN-based image processing systems, and we also provide an implementation of it on Matlab. CCBY
|
|
| 256. |
- She, Huimin, et al.
(författare)
-
A Network-based System Architecture for Remote Medical Applications
- 2007
-
Ingår i: Proceedings of the Asia-Pacific Advanced Network Meeting.
-
Konferensbidrag (refereegranskat)abstract
- Nowadays, the evolution of wireless communication and networktechnologies enables remote medical services to be availableeverywhere in the world. In this paper, a network-based systemarchitecture adopting wireless personal area network (WPAN)protocol IEEE 802.15.4/Zigbee standard and 3G communicationnetworks for remote medical applications is proposed. In theproposed system, the number and type of medical sensors arescalable depending on individual needs. This feature allows thesystem to be flexibly applied in several medical applications.Furthermore, a differentiated service using priority scheduling anddata compression is introduced. This scheme can not only reducetransmission delay for critical physiological signals and enhancebandwidth utilization at the same time, but also decrease powerconsumption of the hand-held personal server which uses batteryas the energy source.
|
|
| 257. |
- She, Huimin, et al.
(författare)
-
Analysis of Traffic Splitting Mechanisms for 2D Mesh Sensor Networks
- 2008
-
Ingår i: International Journal of Software Engineering and Its Applications. - 1738-9984. ; 2:3
-
Tidskriftsartikel (refereegranskat)abstract
- For many applications of sensor networks, it is essential to ensure that messages aretransmitted to their destinations within delay bounds and the buffer size of each sensor nodeis as small as possible. In this paper, we firstly introduce the system model of a mesh sensornetwork. Based on this system model, the expressions for deriving the delay bound and bufferrequirement bound are presented using network calculus theory. In order to balance trafficload and improve resource utilization, three traffic splitting mechanisms are proposed. Andthe two bounds are derived in these traffic splitting mechanisms. To show how our methodapplies to real applications, we conduct a case study on a fresh food tracking application,which monitors the food freshness status in real-time during transportation. The numericalresults show that the delay bound and buffer requirement bound are reduced while applyingtraffic splitting mechanisms. Thus the performance of the whole sensor network is improvedwith less cost.
|
|
| 258. |
- She, Huimin, et al.
(författare)
-
Analytical Evaluation of Retransmission Schemes in Wireless Sensor Networks
- 2009
-
Ingår i: 2009 IEEE VEHICULAR TECHNOLOGY CONFERENCE. - 9781424425167 ; , s. 38-42
-
Konferensbidrag (refereegranskat)abstract
- Retransmission has been adopted as one of the most popular schemes for improving transmission reliability in wireless sensor networks. Many previous works have been done on reliable transmission issues in experimental ways, however, there still lack of analytical techniques to evaluate these solutions. Based on the traffic model, service model and energy model, we propose an analytical method to analyze the delay and energy metrics of two categories of retransmission schemes: hop-by-hop retransmission (HBH) and end-to-end retransmission (ETE). With the experiment results, the maximum packet transfer delay and energy efficiency of these two scheme are compared in several scenarios. Moreover, the analytical results of transfer delay are validated through simulations. Our experiments demonstrate that HBH has less energy consumption at the cost of lager transfer delay compared with ETE. With the same target success probability, ETE is superior on the delay metric for low bit-error-rate (BER) cases, while HBH is superior for high BER cases.
|
|
| 259. |
- She, Huimin, et al.
(författare)
-
Deterministic Worst-case Performance Analysis for Wireless Sensor Networks
- 2008
-
Ingår i: Proceedings of the International Wireless Communications and Mobile Computing Conference. - 9781424422029 ; , s. 1081-1086
-
Konferensbidrag (refereegranskat)abstract
- Dimensioning wireless sensor networks requires formal methods to guarantee network performance and cost in any conditions. Based on network calculus, this paper presents a deterministic analysis method for evaluating the worst-case performance and buffer cost of sensor networks. To this end, we introduce three general traffic flow operators and derive their delay and buffer bounds. These operators are general because they can be used in combination to model any complex traffic flowing scenarios in sensor networks. Furthermore, our method integrates variable duty cycle to allow the sensor nodes to operate at lower rates thus saving power. Moreover, it incorporates traffic splitting mechanisms in order to balance network workload and nodes' buffers. To show how our method applies to real applications, we conduct a case study on a fresh food tracking application, which monitors the food freshness in realtime. The experimental results demonstrate that our method can be either used to perform network planning before deployment, or to conduct network reconfiguration after deployment.
|
|
| 260. |
- She, Huimin, et al.
(författare)
-
Modeling and Analysis of Rayleigh Fading Channels using Stochastic Network Calculus
- 2011
-
Konferensbidrag (refereegranskat)abstract
- Deterministic network calculus (DNC) is not suitable for deriving performance guarantees for wireless networks due to their inherently random behaviors. In this paper, we develop a method for Quality of Service (QoS) analysis of wireless channels subject to Rayleigh fading based on stochastic network calculus. We provide closed-form stochastic service curve for the Rayleigh fading channel. With this service curve, we derive stochastic delay and backlog bounds. Simulation results verify that the bounds are reasonably tight. Moreover, through numerical experiments, we show the method is not only capable of deriving stochastic performance bounds, but also can provide guidelines for designing transmission strategies in wireless networks.
|
|
