| 1. |
- Delsing, Jerker, et al.
(författare)
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Building System of Systems with SOA Technology : A Smart House Use Case
- 2014
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Ingår i: Industrial Cloud-Based Cyber-Physical Systems. - Cham : Encyclopedia of Global Archaeology/Springer Verlag. - 9783319056234 - 9783319056241 ; , s. 219-230
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Bokkapitel (refereegranskat)abstract
- The IMC-AESOP architecture has been used to implemente a smart house demonstration. Six different systems has been integrated with local (802.11, 802.15.4) and global (telecom) communication. The six systems integrated are: Car arrival detection system, Garage door opening system, House security system, External house lightning system, External electrical outlet system, House energy control system. The SOA technologies used are CoAP and EXI using SenML to encode the services. Engineering tools have been used to simulate the usage scenario and provide prediction of system behaviour.
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| 2. |
- Eriksson, Johan, et al.
(författare)
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Real-time for the masses, step 1: Programming API and static priority SRP kernel primitives
- 2013
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Ingår i: 2013 8th IEEE International Symposium on Industrial and Embedded Systems (SIES 2013). - Piscataway, NJ : IEEE Communications Society. ; , s. 110-113
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Konferensbidrag (refereegranskat)abstract
- Lightweight Real-Time Operating Systems have gained widespread use in implementing embedded software on lightweight nodes. However, bare metal solutions are chosen, e.g., when the reactive (interrupt-driven) paradigm better matches the programmer’s intent, when the OS features are not needed, or when the OS overhead is deemed too large. Moreover, other approaches are used when real-time guarantees are required. Establishing real-time and resource guarantees typically requires expert knowledge in the field, as no turn-key solutions are available to the masses.In this paper we set out to bridge the gap between bare metal solutions and traditional Real-Time OS paradigms. Our goal is to meet the intuition of the programmer and at the same time provide a resource-efficient (w.r.t. CPU and memory) implementation with established properties, such as bounded memory usage and guaranteed response times. We outline a roadmap for Real-Time For the Masses (RTFM) and report on the first step: an intuitive, platform-independent programming API backed by an efficient Stack Resource Policy-based scheduler and a tool for kernel configuration and basic resource and timing analysis.
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| 3. |
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| 4. |
- Nappey, Philippe, et al.
(författare)
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Migration of a legacy plant lubrication system to SOA
- 2013
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Ingår i: 39th Annual Conference of the IEEE Industrial Electronics Society, IECON 2013. - : IEEE Communications Society. ; , s. 7440-7445
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Konferensbidrag (refereegranskat)abstract
- Supervision and control systems are being deployed in industrial environments such as mining plants and manufacturing facilities to ensure a continuous and effective production at a minimum cost. Such systems monitor a whole range of devices and collect their data for several purposes like maintenance and control operations.
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| 5. |
- Nappey, Philippe, et al.
(författare)
-
Migration of a Legacy Plant Lubrication System to SOA
- 2014
-
Ingår i: Industrial Cloud-Based Cyber-Physical Systems. - Cham : Encyclopedia of Global Archaeology/Springer Verlag. - 9783319056234 - 9783319056241 ; , s. 167-182
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Bokkapitel (refereegranskat)abstract
- IMC-AESOP investigations have been articulated around key use cases in order to better capture user needs and corresponding requirements. This particular use case explores how Service-Oriented Architecture (SOA) can ease the installation and maintenance of one of the lubrication system of the world’s largest underground iron mine run by LKAB in north Sweden, with a focus on migration aspects. We demonstrate that the loose coupling provided by the SOA approach combined with the eventing capabilities of Event Driven Architecture (EDA) can benefit to both engineering, installation and maintenance of an industrial process control system, with the exception of hard real-time based control loops.
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| 6. |
- Sundström, Nils, et al.
(författare)
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Field evaluation of a new method for estimation of liquid water content and snow water equivalent of wet snowpacks with GPR
- 2013
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Ingår i: Hydrology Research. - : IWA Publishing. - 1998-9563 .- 0029-1277 .- 2224-7955. ; 44:4, s. 600-613
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Tidskriftsartikel (refereegranskat)abstract
- Estimates of snow water equivalent (SWE) with ground-penetrating radar can be used to calibrate and validate measurements of SWE over large areas conducted from satellites and aircrafts. However, such radar estimates typically suffer from low accuracy in wet snowpacks due to a built-in assumption of dry snow. To remedy the problem, we suggest determining liquid water content from path-dependent attenuation. We present the results of a field evaluation of this method which demonstrate that, in a wet snowpack between 0.9 and 3 m deep and with about 5 vol% of liquid water, liquid water content is underestimated by about 50% (on average). Nevertheless, the method decreases the mean error in SWE estimates to 16% compared to 34% when the presence of liquid water in snow is ignored and 31% when SWE is determined directly from two-way travel time and calibrated for manually measured snow density.
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| 7. |
- Sundström, Nils, et al.
(författare)
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Modeling and simulation of GPR wave propagation through wet snowpacks : testing the sensitivity of a method for snow water equivalent estimation
- 2012
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Ingår i: Cold Regions Science and Technology. - : Elsevier BV. - 0165-232X .- 1872-7441. ; 74-75, s. 11-20
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Tidskriftsartikel (refereegranskat)abstract
- Snow water equivalent (SWE) of a snowpack is an important input to the distributed snow hydrological models used for runoff predictions in areas with annual snowpacks. Since the conventional method of manually measuring SWE is very time-consuming, more automated methods are being adopted, such as using ground penetrating radar operated from a snowmobile with SWE estimated from radar wave two-way travel time. However, this method suffers from significant errors when liquid water is present in the snow.In our previous work, a new method for estimating SWE of wet snowpacks from radar wave travel times and amplitudes was proposed, with both these parameters obtained from a common mid-point survey. Here we present a custom ray-based model of radar wave propagation through wet snowpacks and results of MATLAB simulations conducted to investigate the method's sensitivity to measurement errors and snowpack properties. In particular, for a single-layer snowpack up to 2.1 m deep and with liquid water content up to 4.5% (by volume), the simulations indicate that SWE can be estimated with an error of ± 5% or less if (a) the noise (measurement errors) in the resulting amplitude has a standard deviation less than 15% and(b) the noise in two-way travel time has a standard deviation less than 0.075 ns (22.5% and 0.15 ns for a snowpack less than 1.3 m deep).
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| 8. |
- van Deventer, Jan, et al.
(författare)
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Platform independent system integration
- 2011
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Ingår i: SAE 2011 World Congress & Exhibition Technical Papers. - Warrendale, Pa : Society of Automotive Engineers, Incorporated.
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Konferensbidrag (refereegranskat)abstract
- This paper presents and demonstrates a paradigm to implement automotive systems based on their specifications in a manner that is platform independent. The advantage is to have the same software used in simulation as on different types of micro-controller in a vehicle as well as to ease the integration of different systems. The paradigm is to model the system’s components as reactive objects and to use the Timber kernel to schedule their (re)actions. The demonstration is done by developing an anti-lock braking system within the simulation software CarSim and Simulink, which is then evaluated on a braking maneuver over a surface with different coefficient of adhesion from side to side (split mu).
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| 9. |
- Wiklander, Jimmie, et al.
(författare)
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Enabling component-based design for embedded real-time software
- 2009
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Ingår i: Journal of Computers. - : International Academy Publishing (IAP). - 1796-203X. ; 4:12, s. 1309-1321
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Tidskriftsartikel (refereegranskat)abstract
- The increasing complexity of embedded software calls for a new, more efficient design approach. A natural choice is to use well-established component-based design; however, its adoption to design of embedded software has been slow and riddled with difficulties. It can be argued that these problems are due to the following peculiarities of embedded systems. Firstly, the tight integration between hardware and software, typical for embedded systems, makes it virtually impossible to model and implement software separately from hardware. Secondly, it is difficult to express timing requirements, an intrinsic part of functionality of many embedded systems, in dataflow abstractions traditionally used in component-based design. We propose to overcome these difficulties by introducing a uniform, consistent modeling of both hardware and software and by integrating timing requirements into the model. We present a modeling framework based on the notions of reactive objects and time-constrained reactions, which enables component-based design of embedded real-time systems. Within this framework, functionality of both hardware and software components is defined in terms of reactions to discrete external events, and timing requirements are specified for each reaction relative to the event that triggered it. We also present a detailed software design methodology for embedded real-time systems based on our modeling framework.
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| 10. |
- Wiklander, Jimmie, et al.
(författare)
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Personal alarm device: a case study in component-based design of embedded real-time software
- 2011
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Designing software for embedded systems is complicated by such factors as the tight integration between software and hardware, scarceness of available resources, and hard real-time requirements. In our earlier work we proposed a component-based approach based on modeling both hardware and software using reactive objects and time-constrained reactions, which should allow us to overcome these difficulties. We also presented a software design methodology for embedded real-time systems.Here we describe a system developed using this methodology and discuss its advantages. The system is a personal alarm device that should be worn at the waist of a person and that should detect his or her fall and send an alarm signal. The implementation of the system was verified using a Simulink-based simulator. The simulation demonstrated that, even though calculation of acceleration was simplified to allow for an efficient execution on a resource-constrained platform, fall detection remained satisfactory.The case study demonstrates the advantages of the proposed software design methodology, including the fact that functional and timing properties of a system model can be preserved during implementation process by means of a seamless transition between a model and an implementation.
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