| 1. |
- Claesson, Åsa, et al.
(författare)
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lntegrated Optical Fiber Sensors in Additive Manufactured Metal Components for Smart Manufacturing Applications
- 2019
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Ingår i: Smart Systems Integration; 13th International Conference and Exhibition on Integration Issues of Miniaturized Systems.
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Konferensbidrag (refereegranskat)abstract
- This work combines fiber optic sensors with additive manufacturing to enable integration of temperature and strain sensors in metal components. In this paper, we present a fiber optic sensor network integrated in press hardening tools to monitor the contact between the tool and the metal sheet during forming operation. The tools are manufactured through metal powder bed fusion using laser melting processes (PBF-SLM), after which the tools are prepared for sensor integration. A demonstrator press hardening tool with integrated fiber optic sensors was heated using an electric heat foil and the sensor measurements was compared to a thermal simulation model. The sensor technology is based on Fiber Bragg Gratings (FBGs), integrated at several positions along the optical fiber. FBGs are in-fiber sensors that are multiplexed. lt is possible to place hundreds of FBG sensors along one single fiber, thus allowing for quasidistributed sensing of temperature or strain. The optical fiber itself can be less than 100 micrometer in diameter, allowing for sensing at several points in a minimally invasive way, when integrated in a tool or component.
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| 2. |
- Edman, Frida, et al.
(författare)
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Potential to reduce climate impact with digitalisation in agriculture – literature review and a case study of milk
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The agricultural sector in Sweden needs to reduce greenhouse gas (GHG) emissions. Digitalisation has the potential to contribute to this reduction. The term digitalisation is used to describe a process for digital transformation of products and processes. The purpose is to enable better decisions by using an increased insight through collecting data, and to process the collected data using different smart algorithms. In this report, we present a literature review on research of the potential to reduce climate impact with digitalisation in agriculture. The result of the literature review was applied on a case study, where different scenarios with varying degrees of digitalisation were tested to quantify possible reductions in GHG emissions when introducing digitalisation techniques at a Swedish dairy farm. The results shows that implementation of various digitalisation technologies at a Swedish dairy farm has a potential to reduce the carbon footprint of Swedish milk by 16 %. Precision livestock farming shows the largest potential with an estimated reduction of 14 %, primarily due to feed efficiency and improved animal health and longevity, reducing the total number of animals while maintaining high milk output. It is however important to evaluate the whole system, as changes in the dairy system might impact other farms and food producing systems. This indicates a need for research to further investigate the potential GHG reduction when introducing digitalisation in agriculture.
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| 3. |
- Forsström, Stefan, et al.
(författare)
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A Flexible Sensor and Actuator Gateway for Internet-of-Things Applications
- 2015
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Konferensbidrag (refereegranskat)abstract
- There is currently a vast amount of sensors, actuators, and other devices intended to create the Internet-of-Things. However, most of these only operate within a particular manufacturer’s ecosystem and with a limited set of compatible hardware. In response to this we present a general sensor and actuator gateway for the Internet-of-Things, which provides the flexibility to easily exchange sensor and actuator hardware. The gateway is implemented as a proof-of-concept prototype that is verified to be compatible with a wide range of commercial off the shelf hardware. It is also shown to be able to run the SensibleThings platform, a fully distributed and open communication platform for Internet-Things applications.
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| 4. |
- Forsström, Stefan, et al.
(författare)
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Challenges when Realizing a Fully Distributed Internet-of-Things - How we Created the SensibleThings Platform
- 2014
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Ingår i: ICDT 2014, The Ninth International Conference on Digital Telecommunications. - 9781612083162 ; , s. 13-18
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Konferensbidrag (refereegranskat)abstract
- The SensibleThings platform is an open source architecturefor enabling Internet-of-Things based applications.During its development, multiple problems have been faced andsolved, for example issues related to networking, information dissemination,sensors, and application access. This paper describesthese problems and the technical solutions that are implementedin the platform. We also present the current progress and aseries of demonstrator applications, which show the wide rangeof possibilities enabled by the platform. Finally, we present futurework and how it will be used in future research endeavors andcommercial interests.
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| 5. |
- Forsström, Stefan, et al.
(författare)
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Dissemination of Anonymised Context Information by Extending the DCXP Framework
- 2010
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Ingår i: Lecture Notes of the Institute for Computer Sciences Social Informatics and Telecommunications Engineering Volume 32. - : Springer. ; , s. 57-66
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Konferensbidrag (refereegranskat)abstract
- The increasing ubiquity of context aware services and systems has been primarily underpinned by the use of centralised servers employing protocols that do no scale well for real time distribution and acquisition of neither sensor data nor dependent services.Any shift from this generic sensor framework mandated a new thinking where sensor data was capable of being propagated in real time using protocols and data models which serve to reduce unnecessary communication overhead. DCXP is proposed as an alternative architecture for the real time distribution of context information to ubiquitous mobile services.As a P2P based distributed protocol, it inherently poses the challenge of user anonymity across the system. In this paper we briefly present DCXP along with further work to enable the anonymised dissemination of sensor information within the architecture.Such a solution would have a negligible impact on the overall scalability and performance of DCXP.
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| 6. |
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| 7. |
- Forsström, Stefan, et al.
(författare)
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Estimating Contextual Situations using Indicators from Smartphone Sensor Values
- 2014
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Ingår i: Proceedings - 2014 IEEE International Conference on Internet of Things, iThings 2014, 2014 IEEE International Conference on Green Computing and Communications, GreenCom 2014 and 2014 IEEE International Conference on Cyber-Physical-Social Computing, CPS 2014. ; , s. 243-250
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Konferensbidrag (refereegranskat)abstract
- Current context-aware applications often use thelocation of a user as the only indication of the current situation.These existing applications are therefore limited in their situationawareness, because of the poor indoor resolution of the locationsensor and its high resource consumption. In response to theselimitations we present an approach to estimate the contextualsituation of a user without using resource inefficient locationsensors. Our proposed solution utilizes a wide range of lowpowered sensors, together with two modified machine learningtechniques to estimate the situation in a more resource efficientmanner. Simulations and a proof-of-concept application show thatthe situation of a user can be determined within 50 ms at anaccuracy above 90%, when only using the low energy sensorsavailable on a smartphone and its limited processing power.
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| 8. |
- Forsström, Stefan, et al.
(författare)
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Location-Based Ubiquitous Context Exchange in Mobile Environments
- 2010
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Ingår i: Lecture Notes of the Institute for Computer Sciences Social Informatics and Telecommunications Engineering Vol 68. - : Springer. ; , s. 177-187
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Konferensbidrag (refereegranskat)abstract
- Context-aware applications and services require ubiquitous access to context information of users. The limited scalability of centralized servers used in the provisioning of context information mandates the search for scalable peer-to-peer protocols. Furthermore, unnecessary signaling must be avoided in large-scale context networks, when location-based services only require nodes in a certain area with which to communicate context. To this end, we propose a lightweight model for composing and maintaining unstructured location-scoped networks of peer-to-peer nodes, which gossips in order to ensure quality of service for each user. The model is implemented in a prototype application running in a mobile environment, which is evaluated with respect to real-time properties. This model can also be extended to include more context dimensions, other than location.
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| 9. |
- Forsström, Stefan, et al.
(författare)
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MediaSense - an Internet of Things Platform for Scalable and Decentralized Context Sharing and Control
- 2012
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Ingår i: ICDT 2012, The Seventh International Conference on Digital Telecommunications. - : International Academy, Research and Industry Association (IARIA). - 9781612081939 ; , s. 27-32
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Konferensbidrag (refereegranskat)abstract
- Research in Internet-of-Things infrastructures has so far mainly been focused on connecting sensors and actuators to the Internet, while associating these devices to applications via web services. This has contributed to making the technology accessible in areas such as smart-grid, transport, health, etc. These early successes have hidden the lack of support for sensor-based applications to share information and limitations in support for applications to access sensors and actuators globally. We address these limitations in a novel open-source platform, MediaSense. MediaSense offers scalable, seamless, real-time access to global sensors and actuators via hetero- geneous network infrastructure. This paper presents a set of requirements for Internet-of-Things applications support, an overview of our architecture, and application prototypes created in order to verify the approach in a test bed with users connected from heterogeneous networks.
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| 10. |
- Forsström, Stefan, 1984-, et al.
(författare)
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Surveying and identifying the communication platforms of the internet of things
- 2018
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Ingår i: 2018 Global Internet of Things Summit, GIoTS 2018. - : IEEE. - 9781538664513
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Konferensbidrag (refereegranskat)abstract
- Research and industry invest time and resources in producing Internet of Things-based services, and the concept of Internet of Things platforms is climbing in the hype cycle for emerging technologies. Consequently, there is a vast number of enabling technologies, making it difficult to find the most suitable platform. The aim and goal of this article is to list and identify the currently available communication platforms for the Internet of Things. In this workwe surveyed the area and found over 128 different platforms for communication of data between things and services, out of which 42 fulfilled our listed basic requirements for being an IoT communication platform.
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