Saad Mubeen

An Elderly Health Care System Using Wireless Sensor Networks at Home

The purpose of this project is to integrate the technologies of wireless sensor networks and public communication networks to construct a healthcare system for senior citizens at home without interfering their daily activities. This system provides 4 main functionalities, including indoor monitoring, outdoor monitoring, activity and health state decision, emergency decision and alarm. JTH has developed a prototype of wireless sensor networks, an interconnection platform and a service management platform to support large scale data interconnections and real-time activity and health state reports to related persons (e.g. doctors or nurses, elder-self, elders’ relatives) via all popular communication approaches, such as automatic voice telephone call, SMS or Email etc. In this paper, the system functions and implementation approaches are introduced. A series of experiments results shows that the system performs high validity and reliability.

Extending schedulability analysis of Controller Area Network (CAN) for mixed (periodic/sporadic) messages

The schedulability analysis of Controller Area Network (CAN) developed by the research community is able to compute the response times of CAN messages that are queued for transmission periodically or sporadically. However, there are a few high-level protocols for CAN such as CANopen and Hägglunds Controller Area Network (HCAN) that support the transmission of mixed messages as well. A mixed message can be queued for transmission both periodically and sporadically. Thus, it does not exhibit a periodic activation pattern. The existing analysis of CAN does not support the analysis of mixed messages. We extend the existing analysis to compute the response times of mixed messages. The extended analysis is generally applicable to any high level protocol for CAN that uses any combination of periodic, event and mixed (periodic/event) transmission of messages.

Worst-case response-time analysis for mixed messages with offsets in Controller Area Network

The existing response-time analysis for Controller Area Network (CAN) does not support mixed messages that are scheduled with offsets. Mixed messages are implemented by several high-level protocols for CAN that are used in the automotive industry. We extend the existing offset-based analysis which is applicable to any high-level protocol for CAN that uses periodic, sporadic and mixed transmission of messages. Moreover, we implement the extended analysis as a standalone simulator that will be integrated as a plug-in with the existing industrial tool suite (Rubus-ICE). The experiments, that we performed, indicate that it is possible to achieve up to 4.48% improvement in schedulability when mixed messages are scheduled with offsets.

Support for End-to-End Response-Time and Delay Analysis in the Industrial Tool Suite: Implementation Issues, Experiences and a Case Study

In this paper we discuss the implementation of the state-of-the-art end-to-end response-time and delay analysis as two individual plug-ins for the existing industrial tool suite Rubus-ICE. The tool ...

Communications-oriented development of component-based vehicular distributed real-time embedded systems

We propose a novel model- and component-based technique to support communications-oriented development of software for vehicular distributed real-time embedded systems. The proposed technique supports modeling of legacy nodes and communication protocols by encapsulating and abstracting the internal implementation details and protocols. It also allows modeling and performing timing analysis of the applications that contain network traffic originating from outside of the system such as vehicle-to-vehicle, vehicle-to-infrastructure, and cloud-based applications. Furthermore, we present a method to extract end-to-end timing models to support end-to-end timing analysis. We also discuss and solve the issues involved during the extraction of these models. As a proof of concept, we implement our technique in the Rubus Component Model which is used for the development of software for vehicular embedded systems by several international companies. We also conduct an application-case study to validate our approach.

Response-time analysis of mixed messages in Controller Area Network with priority- and FIFO-queued nodes

The Controller Area Network (CAN) is a widely used real-time network in automotive domain. We identify that the existing response-time analysis for messages in CAN with some of the connected nodes implementing priority queues while others implementing FIFO queues does not support the analysis of mixed messages. The existing analysis assumes that a message is queued for transmission either periodically or sporadically. However, a message can also be queued both periodically and sporadically using a mixed transmission mode implemented by several high-level protocols for CAN used in the industry today. We extend the existing analysis which is generally applicable to any high-level protocol for CAN (with priority-and FIFO-queued nodes) that uses periodic, sporadic, and mixed transmission of messages.

Analyzable Modeling of Legacy Communication in Component-Based Distributed Embedded Systems

We present extensions to the existing industrial component model Rubus Component Model (RCM). By introducing special purpose components to encapsulate and abstract the communication protocols in distributed embedded systems we allow use of legacy nodes and legacy protocols in a component-based and model-based software engineering environment. With the addition of these components, RCM will be able to support state-of-the-practice development processes of distributed embedded systems where communication rules are defined early in the development process. The proposed extension also allows model-based and component-based development of new nodes that are deployed in the legacy systems that use predefined communication rules. We also demonstrate how an end-to-end timing model can be extracted from a distributed embedded system modeled with extended RCM. The extracted model is then used to perform an end-to-end timing analysis that we implemented in the Rubus Analysis Framework.

Designing Efficient Source Routing for Mesh Topology Network on Chip Platforms

Efficient on-chip communication is very important for exploiting enormous computing power available on a multi-core chip. Network on Chip (NoC) has emerged as a competitive candidate for implementing on-chip communication. Routing algorithms significantly affect the performance of a NoC. Most of the existing NoC architectural proposals advocate distributed routing algorithms for building NoC platforms. Although source routing offers many advantages, researchers avoided it due to its apparent disadvantage of larger header size requirement that results in lower bandwidth utilization. In this paper we make a strong case for the use of source routing for NoCs, especially for platforms with small sizes and regular topologies. We present a methodology to compute application specific efficient paths for communication among cores with a high degree of load balancing. The methodology first selects the most appropriate deadlock free routing algorithm, from a set of routing algorithms, based on the application’s traffic patterns. Then the selected (possibly adaptive) routing algorithm is used to compute efficient static paths with the goal of link load balancing. We demonstrate through simulation based evaluation that source routing has a potential of achieving higher performance, for example up to 28% lower latency even at medium load, as compared to distributed routing. A simple scheme is proposed for encoding of router ports to reduce the header overhead. A generic simulator was developed for evaluation and performance comparison between source routing and distributed routing. We also designed a router to support source routing for mesh topology NoC platforms.

Extending response-time analysis of Controller Area Network (CAN) with FIFO queues for mixed messages

Existing response-time analysis for Controller Area Network (CAN) messages in networks where some nodes implement FIFO queues while others implement priority queues, assumes that at every node, CAN messages are queued for transmission periodically or sporadically. However, there are a few high level protocols for CAN such as CANopen and Hägglunds Controller Area Network (HCAN) that support the transmission of mixed messages as well. A mixed message can be queued for transmission both periodically and sporadically. The existing analysis of CAN with FIFO queues does not support the analysis of mixed messages. We extend the existing response-time analysis of mixed-type CAN messages. The extended analysis can compute the response-times of mixed (periodic/ sporadic) messages in the CAN network where some nodes use FIFO queues while others use priority queues.

Support for Holistic Response-Time Analysis in an Industrial Tool Suite: Implementation Issues, Experiences and a Case Study

The process of implementing and integrating state-of-the-art real-time analysis techniques with an existing industrial tool suite for the development of Distributed Real-time Embedded (DRE) systems offers many challenges. The implementer has to not only code and implement the analysis in the tool suite, but also deal with several issues such as extraction of unambiguous timing and tracing information from the design model. In this paper we present an implementation of the Holistic Response-Time Analysis (HRTA) as a plug-in for an industrial tool suite Rubus-ICE that is used for component-based development of DRE systems. We discuss and solve the issues encountered and highlight the experiences gained during the process of implementation, integration and evaluation of HRTA plug-in. We also provide a proof of concept by modeling an automotive application (autonomous cruise control system) using component-based development and analyzing it with HRTA plug-in.