Software Engineering featuring the Zachman Taxonomy (2009)
Stoll, Pia, Wall, Anders, Norström, Christer
Software engineering of today must consider organizational- and business issues as well as architectural issues for fast manufacturing of software. The semantics in a taxonomic scheme including...
Approximate timing analysis of complex legacy real-time systems using simulation optimization (2008)
Lu, Yue, Bohlin, Markus, Kraft, Johan, Kreuger, Per, Nolte, Thomas, Norström, Christer
Goran Mustapic, Christer Norström, Anders Wall, Ivica Crnkovic, Kristian S, Johan Andersson, ...
last decade. In this report, we have collected data from a number of real systems, which are successful and complex industrial systems. We tried to identify factors that have significant influence on...
Title: Vehicular Embedded Control Systems (2008)
Ivica Crnkovic, Johan Fredriksson, Hans Hansson, Jörgen Hansson, Joel Huselius, Mikael Nolin, ...
This chapter focuses on the state of practice of embedded control systems by describing existing software and hardware architectures. Compared to chapter one, this chapter provides more detail on the...
Verifying Temporal Constraints on Data in Multi-Rate Transactions using Timed Automata (2008)
Anders Wall, Kristian S, Jukka Mäki-turja, Christer Norström, Wang Yi
Transactions involving multiple tasks, possibly with different period times, are common constructs used in the design of real-time systems. Data flowing through a transaction is usually subject to...
Introducing Snapshots to Database Pointer Transactions ∗ (2008)
Dag Nyström, Mikael Nolin, Christer Norström
We present 2V-DBP-SNAP, an algorithm that allow hard real-time tasks in an embedded real-time control system to read a snapshot of a number of data elements in a real-time database. Furthermore,...
Guiding Architectural Decisions with the Influencing Factors Method (2008)
Stoll, Pia, Wall, Anders, Norström, Christer
The Influencing Factors (IF) method guides the architect through stakeholders’ concerns to architectural decisions in line with current business goals. The result is a set of requirements on...
Frame Packing in Real-Time Communication (2007)
Kristian S, Christer Norström, Magnus Ahlmark
A common computational model in distributed embedded systems is that the nodes exchange signals via a network. Most often a signal represents the state of some physical device and has a signal size...
Jakob Axelsson, Joakim Fröberg, Hans Hansson, Christer Norström, Kristian S, Björn Villing
In recent years, networking issues have become more and more important in the design of vehicle control systems. In the beginning of the 1990s a vehicle control system was built up by ‘simple ’...
Managing Complex Temporal Requirements in Real-Time Control Systems (2007)
Design and implementation of motion control applications includes the transition from control design to real-time system implementation. To make this transition smooth, the specification model for...
Managing Temporal Constraints in Control Systems (2007)
Design and implementation of motion control applications include the mapping of control design to real-time system implementation. Important parameters from control design include deviation from...
Product Line Architectures for Embedded Real-Time Systems (2007)
Anders Wall, Kristian S, Christer Norström
In this paper, we propose the use of product line architectures in order to shorten time to market, cut cost, and to reduce maintenance when developing embedded real-time systems. A development...
Software Development Tools for Embedded Databases in Embedded Real-Time Systems (2007)
Aleksandra Zagorac, Dag Nyström, Jörgen Hansson, Christer Norström
In the last years the deployment of embedded and mobile computing systems has increased dramatically. This is particularly true if one analyzes the growing market for cellular phones and the...
Effects of varying phasings of message queuings in CAN based systems (2007)
Thomas Nolte, Hans Hansson, Christer Norström
This article presents and illustrates the effects on message response times by considering variations in phasings of message queuings in distributed system using the CAN bus. Traditional worst-case...
Hard Real-Time in a Soft World (2007)
Hans Hansson, Christer Norström, Sasikumar Punnekkat
In cost conscious industries, such as automotive, it is imperative for designers to adhere to policies that reduce system resources to the extent feasible, even for safety-critical subsystems....
Verifying Temporal Constraints on Data in Multi-Rate Transactions using Timed Automata (2007)
Anders Wall, Kristian S, Jukka Mäki-turja, Christer Norström, Wang Yi
Transactions involving multiple tasks, possibly with different period times, are common constructs used in the design of real-time systems. Data flowing through a transaction is usually subject to...
Validating Timing Models of Industrial Real-Time Systems (2007)
Johan Andersson, Anders Wall, Christer Norström
Abstract. When analyzing a model of any kind, in order to get confidence in the analysis result it is necessary to have confidence in the model. If a model describes the timing of a complex software...
Jakob Axelsson, Joakim Fröberg, Hans Hansson, Christer Norström, Kristian Sandström, Kristian S, ...
In recent years, networking issues have become more and more important in the design of vehicle control systems. In the beginning of the 1990s a vehicle control system was built up by `simple'...
Validating Temporal Behavior Models of Complex Real-Time Systems (2007)
Johan Andersson, Anders Wall, Christer Norström
When constructing a model of the behavior of a software system, model validation is necessary in order to assure that the model accuratly describes the system at an appropriate level of abstraction....
Underwater 3-D imaging with laser triangulation (2006)
The objective of this master thesis was to study the performance of an active triangulation system for 3-D imaging in underwater applications. Structured light from a 20 mW laser and a conventional...
Underwater 3-D imaging with laser triangulation (2006)
The objective of this master thesis was to study the performance of an active triangulation system for 3-D imaging in underwater applications. Structured light from a 20 mW laser and a conventional...
Extracting simulation models from complex industrial realtime systems (2006)
Johan Andersson, Joel Huselius, Christer Norström, Anders Wall
A modeling process is presented for extracting timingaccurate simulation models from complex industrial realtime systems. The process is supported by two methods for tool-supported model extraction,...
Anders Wall, Johan Andersson, Christer Norström
Abstract. A common problem with long-lived large industrial software systems such as telecom and industrial automation systems is the increasing complexity and the lack of formal models enabling...
Dag Nyström, Mikael Nolin, Christer Norström, Jörgen Hansson
soft real-time management, maintenance, or user-interface In this paper we present a concurrency control algo- applications. rithm that allows co-existence of soft real-time, relational We have...
Jakob Axelsson, Joakim Fröberg, Hans Hansson, Christer Norström, Kristian S, Björn Villing
In recent years, networking issues have become more and more important in the design of vehicle control systems. In the beginning of the 1990s a vehicle control system was built up by ‘simple ’...
COMET: A Component-Based Real-Time Database for Automotive Systems (2004)
Dag Nyström, Mikael Nolin, Christer Norström, Jörgen Hansson
With the increase of complexity in automotive control systems, the amount of data that needs to be managed is also increasing. Using a real-time database management system (RTDBMS) as a tightly...
Ra Tešanović, Dag Nyström, Jörgen Hansson, Christer Norström
Abstract — Increasing complexity of real-time systems, and demands for enabling their configurability and reusability are strong motivations for applying new software engineering principles, such...
Pessimistic Concurrency Control and Versioning to Support Database Pointers (2004)
Dag Nyström, Mikael Nolin, Christer Norström, Jörgen Hansson
In this paper we present a concurrency control algorithm that allows co-existence of soft real-time, relational database transactions, and hard real-time database pointer transactions in real-time...
Real World Influences on Software Architecture - Interviews with Industrial Systems Experts (2004)
Goran Mustapic, Anders Wall, Christer Norström, Ivica Crnkovic, Kristian S, Joakim Fröberg, ...
Industrial systems are examples of complex and often long-lived systems in which software is playing an increasingly important role. Their architectures play a crucial role in maintaining the...
Norström: Towards Aspectual Component-Based Development of RealTime Systems (2003)
Ra Tešanović, Dag Nyström, Jörgen Hansson, Christer Norström
Abstract. Increasing complexity of real-time systems, and demands for enabling their configurability and tailorability are strong motivations for applying new software engineering principles, such as...
Probabilistic worst-case response-time analysis for the controller area network (2003)
Thomas Nolte, Hans Hansson, Christer Norström
This paper presents a novel approach for calculating a probabilistic worst-case response-time for messages in the Controller Area Network (CAN). CAN uses a bit-stuffing mechanism to exclude forbidden...
The COMET Database Management System (2003)
Dag Nyström, Ra Tešanović, Christer Norström, Jörgen Hansson
The COMET DBMS (component-based embedded real-time database management system) is an experimental database platform. COMET is intended for resourceconstrained embedded vehicle control-systems. The...
Universitetsservice US AB, Stockholm, 2003 (2003)
Ola Redell, Mechatronics Lab, Mechatronics Lab, Christer Norström
KTH and the foundation for strategic research (SSF) through ARTES Methods for performing response time analysis of real-time systems are important, not only for their use in traditional...
Probabilistic Simulation-based Analysis of Complex Real-Time Systems (2003)
Anders Wall, Johan Andersson, Christer Norström
Many industrial real-time systems have evolved over a long period of time and were initially so simple that it was possible to predict consequences of adding new functionality by common sense....
Aleksandra Tesanovic, Dag Nyström, Jörgen Hansson, Christer Norström, A. Tešanović, J. Hansson, ...
requires the integration of new software engineering techniques, such as aspect-oriented and component-based software development, with real-time system development. Since software technology for...
Aleksandra Tešanović, Dag Nyström, Jörgen Hansson, Christer Norström
Increasing complexity in development of real-time systems accompanied by the demand for enabling their configurability requires the integration of aspect-oriented software development with real-time...
Minimizing CAN response-time jitter by message manipulation (2002)
Thomas Nolte, Hans Hansson, Christer Norström
Delay variations (jitter) in computations and communications cause degradation of performance in control applications. There are many sources of jitter, including variations in execution time and bus...
Embedded Databases for Embedded Real-Time Systems: A Component-Based Approach (2002)
Aleksandra Tešanović, Dag Nyström, Jörgen Hansson, Christer Norström
In the last years the deployment of embedded real-time systems has increased dramatically. At the same time, the amount of data that needs to be managed by embedded real-time systems is increasing,...
Components in real-time systems (2002)
Damir Isovic, Christer Norström
Component-based Software Engineering (CBSE) is a promising approach to improve quality, achieve shorter time to market and to manage the increasing complexity of software. Still there are a number of...
Integrating Reliability and Timing Analysis of CAN-Based Systems (2002)
Hans A. Hansson, Thomas Nolte, Student Member, Christer Norström, Associate Member, Associate Member, ...
This paper presents and illustrates a reliability analysis method developed with a focus on Controller-Area-Network -based automotive systems. The method considers the effect of faults on...
Anders Wall, Christer Norström, Hans Hansson
first phase of the project was divided into two tracks: applying timed automata to the design of real-time systems and software architecture description and analysis for real-time systems. Anders...
A Component Model for Embedded Real-Time Software product-Lines (2001)
Anders Wall, Christer Norström
Abstract: This paper proposes a component model suitable for use in the development of embedded real-time systems where resources, such as memory and CPUs, usually are very limited. A precise...
A Simulation based Approach for Estimating the Reliability of Distributed Realtime Systems (2001)
Hans Hansson, Christer Norström, Sasikumar Punnekkat
are often mandated by requirements on reliability as well as timing guarantees. For guaranteeing timing properties, the standard practice is to use various analysis techniques provided by hard...
Experiences from Introducing State-of-the-art Real-Time Techniques in the Automotive Industry (2001)
Christer Norström, Mikael Gustafsson, Kristian S
www.mrtc.mdh.se The use of state-of-the-art real-time techniques in industry remains infrequent. The reason for this, we believe, is three-fold: (1) the lack of commercially available tools, (2) the...
Integrating reliability and timing analysis of CAN-based systems (2000)
Hans Hansson, Christer Norström, Sasikumar Punnekkat
This paper outlines and illustrates a reliability analysis method developed with focus on CAN-based automotive systems. The method considers the effect of faults on schedulability analysis and its...
Findings From Introducing State-of-the-Art Real-Time Techniques in Vehicle Industry (2000)
Christer Norström, Mikael Gustafsson, Kristian Sandström, Kristian S, Jukka Mäki-turja, Nils-Erik Bånkestad
The use of state-of-the-art real-time techniques in industry is still rare. The reason for this is three-folded: (1) the lack of commercially available tools, (2) the lack of methodologies that...
Frame Packing in Real-Time Communication (2000)
Kristian Sandström, Kristian S, Christer Norström, Magnus Ahlmark
A common computational model in distributed embedded systems is that the nodes exchange signals via a network. Most often a signal represents the state of some physical device and has a signal size...
RATAD Reliability And Timing Analysis of Distributed systems (2000)
Hans Hansson, Christer Norström
Modelling and analysis are important tools in the development of safety critical real-time systems. The introduction of state-of-the-art analysis techniques in industry is however rather slow. One...
Timed Automata as Task Models for Event-Driven Systems (1999)
Christer Norstrom And, Christer Norström, Anders Wall
In this paper, we extend the classic model of timed automata with a notion of real time tasks. The main idea is to associate each discrete transition in a timed automaton with a task (an executable...