Embedded Systems (embedded + system)

Distribution by Scientific Domains


Selected Abstracts


Performance evaluation of decision making strategies for an embedded lane departure warning system

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 10 2002
Woong Kwon
An on-board lane departure warning system embedded in a vehicle is composed of a localization module and a decision making module. The decision making module detects unintended lane departure so as to warn the driver of the danger. The performance of a decision making module is crucial to the performance of the total embedded system. This article proposes two heuristic decision making strategies: a lateral offset (LO) based strategy and a time-to-lane crossing (TLC) based strategy. The performance criteria of decision making strategies are proposed as: (1) false alarm rate, and (2) alarm triggering time (ATT). Numerical parameters of both strategies are optimized through numerical simulation, taking the performance criteria into consideration. The proposed strategies are incorporated into the prototype system and evaluated in real expressway experiments. The comparative study of both methods with experimental results shows the applicability of the on-board lane departure warning system. © 2002 Wiley Periodicals, Inc. [source]


Architecture-based semantic evolution of embedded remotely controlled systems

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2003
Lawrence Chung
Abstract Evolution of a software system is a natural process. In most systems, evolution takes place during the maintenance phase of their life cycles. Those systems that have reached their limit in evolution have usually reached their end of useful life and may have to be replaced. However, there are systems in which evolution occurs during the operational phase of their life cycles. Such systems are designed to evolve while in use or, in other words, be adaptable. Semantically adaptable systems are of particular interest to industry as such systems often times adapt themselves to environment change with little or no intervention from their developing or maintaining organization. Since embedded systems usually have a restricted hardware configuration, it is difficult to apply the techniques developed for non-embedded systems directly to embedded systems. This paper focuses on evolution through adaptation and develops the concepts and techniques for semantic evolution in embedded systems. As the first step in the development of a software solution, architectures of software systems themselves have to be made semantically evolvable. In this paper we explore various architectural alternatives for the semantic evolution of embedded systems,these architectures are based on four different techniques that we have identified for semantic evolution in embedded systems. The development of these architectures follows the systematic process provided by the non-functional requirement (NFR) framework, which also permits the architectures to be rated in terms of their evolvability. As the field of embedded systems is vast, this paper concentrates on those embedded systems that can be remotely controlled. In this application domain the embedded system is connected to an external controller by a communication link such as ethernet, serial, radio frequency, etc., and receives commands from and sends responses to the external controller via the communication link. The architectures developed in this paper have been partly validated by applying them in a real embedded system,a test instrument used for testing cell phones. These architectures and techniques for semantic evolution in this application domain give a glimpse of what can be done in achieving semantic evolution in software-implemented systems. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Dynamic scratch-pad memory management with data pipelining for embedded systems

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2010
Yanqin Yang
Abstract In this paper, we propose an effective data pipelining technique, SPDP (Scratch-Pad Data Pipelining), for dynamic scratch-pad memory (SPM) management with DMA (Direct Memory Access). Our basic idea is to overlap the execution of CPU instructions and DMA operations. In SPDP, based on the iteration access patterns of arrays, we group multiple iterations into a block to improve the data locality of regular array accesses. We allocate the data of multiple iterations into different portions of the SPM. In this way, when the CPU executes instructions and accesses data from one portion of the SPM, DMA operations can be performed to transfer data between the off-chip memory and another portion of SPM simultaneously. We perform code transformation to insert DMA instructions to achieve the data pipelining. We have implemented our SPDP technique with the IMPACT compiler, and conduct experiments using a set of loop kernels from DSPstone, Mibench, and Mediabench on the cycle-accurate VLIW simulator of Trimaran. The experimental results show that our technique achieves performance improvement compared with the previous work. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Exploration of communication models in the design of distributed embedded systems

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 3 2007
Kazutaka Kobayashi Non-member
Abstract Distributed embedded systems involve communication in various layers, and therefore their design is more difficult than of single embedded systems. This paper presents how communication exploration can be done in a design process of distributed embedded systems using an example of event-triggered and time-triggered communication. A design process begins from abstract specification without assuming any communication category, then explores the categories in a stepwise manner, followed by physical implementation synthesis. This encourages stepwise decision making, component and framework reuse, and early stage verification. Copyright © 2007 Institute of Electrical Engineers of Japan© 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]


Architecture-based semantic evolution of embedded remotely controlled systems

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2003
Lawrence Chung
Abstract Evolution of a software system is a natural process. In most systems, evolution takes place during the maintenance phase of their life cycles. Those systems that have reached their limit in evolution have usually reached their end of useful life and may have to be replaced. However, there are systems in which evolution occurs during the operational phase of their life cycles. Such systems are designed to evolve while in use or, in other words, be adaptable. Semantically adaptable systems are of particular interest to industry as such systems often times adapt themselves to environment change with little or no intervention from their developing or maintaining organization. Since embedded systems usually have a restricted hardware configuration, it is difficult to apply the techniques developed for non-embedded systems directly to embedded systems. This paper focuses on evolution through adaptation and develops the concepts and techniques for semantic evolution in embedded systems. As the first step in the development of a software solution, architectures of software systems themselves have to be made semantically evolvable. In this paper we explore various architectural alternatives for the semantic evolution of embedded systems,these architectures are based on four different techniques that we have identified for semantic evolution in embedded systems. The development of these architectures follows the systematic process provided by the non-functional requirement (NFR) framework, which also permits the architectures to be rated in terms of their evolvability. As the field of embedded systems is vast, this paper concentrates on those embedded systems that can be remotely controlled. In this application domain the embedded system is connected to an external controller by a communication link such as ethernet, serial, radio frequency, etc., and receives commands from and sends responses to the external controller via the communication link. The architectures developed in this paper have been partly validated by applying them in a real embedded system,a test instrument used for testing cell phones. These architectures and techniques for semantic evolution in this application domain give a glimpse of what can be done in achieving semantic evolution in software-implemented systems. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Test processes in software product evolution,a qualitative survey on the state of practice

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 1 2003
Per Runeson
Abstract In order to understand the state of test process practices in the software industry, we have conducted a qualitative survey, covering software development departments at 11 companies in Sweden of different sizes and application domains. The companies develop products in an evolutionary manner, which means either new versions are released regularly, or new product variants under new names are released. The survey was conducted through workshop and interview sessions, loosely guided by a questionnaire scheme. The main conclusions of the survey are that the documented development process is emphasized by larger organizations as a key asset, while smaller organizations tend to lean more on experienced people. Further, product volution is performed primarily as new product variants for embedded systems, and as new versions for packaged software. The development is structured using incremental development or a daily build approach; increments are used among more process-focused organizations, and daily build is more frequently utilized in less process-focused organizations. Test automation is performed using scripts for products with focus on functionality, and recorded data for products with focus on non-functional properties. Test automation is an issue which most organizations want to improve; handling the legacy parts of the product and related documentation presents a common problem in improvement efforts for product evolution. Copyright © 2003 John Wiley & Sons, Ltd. [source]