| 1. |
- Birk, Wolfgang, et al.
(författare)
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Project: iRoad
- 2011
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Annan publikation (populärvet., debatt m.m.)
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| 2. |
- Carlsson, Oscar, et al.
(författare)
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Migration of industrial process control systems to service-oriented architectures
- 2018
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Ingår i: International journal of computer integrated manufacturing (Print). - : Taylor & Francis. - 0951-192X .- 1362-3052. ; 31:2, s. 175-198
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Tidskriftsartikel (refereegranskat)abstract
- The use of Service Oriented Architectures (SOAs) in industrial automation promises an improved cross-layer integration as well as a functionality decoupled from the technical implementation. Compared with the earlier investigated manufacturing industry, control systems in the process industry reveal additional challenges in terms of migration from a legacy control system to an SOA control system.The successful migration of a highly integrated process control system, without reducing reliability or availability and, at the same time, preserving functionality and productivity, requires a detailed plan and certain specialised technology.This paper presents the challenges in the migration of a process control system and proposes a structured method for migration. The migration procedure proposed comprises four steps: initiation, configuration, data processing, and control execution. A technology demonstration at a pelletizing plant illustrates how the first of these steps could be implemented.
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| 3. |
- Berrebi, Jonathan, et al.
(författare)
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Ultrasonic flow metering errors due to pulsating flow
- 2004
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Ingår i: Flow Measurement and Instrumentation. - : Elsevier BV. - 0955-5986 .- 1873-6998. ; 15:3, s. 179-185
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Tidskriftsartikel (refereegranskat)abstract
- Transit-time ultrasonic flow meters present some advantages over other flow meters for district heating industries. They are both accurate and non-intrusive. It is well-known that ultrasonic flow meters are sensitive to installation effects. Installation effects could be static or dynamic. Among the possible dynamic installation effects is pulsating flow. The influence of pulsating flow on the prediction and the zero-crossing operations is investigated. Expressions are found for the prediction error and the zero-crossing error. The relative errors due to the prediction and the zero-crossing are plotted. The prediction error can reach dramatic values while the zero-crossing operation is hardly influenced by flow pulsations.
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| 4. |
- Carlander, Carl, et al.
(författare)
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Temperature and installation effects on small commercial ultrasonic flow meters
- 2000
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Konferensbidrag (refereegranskat)abstract
- Experimental work has been performed on a selection of small ultrasonic flow meters for water. This work was accomplished in order to investigate the in fluence of temperature and flow profile disturbances on the performance of flow meters in district heating applications. The flow meters tested were all ultrasonic flow meters of sing-around type. The selection of flow meters contains in total seven meters of three different brands. All meters have a flow range from 0.015 m3/h to 1.5 m3/h. These meters are commonly used in heat meters in small district heating subscriber stations. The flow meters are presented without identification. All tests were performed in a flow meter calibration facility and in a flow range including the minimum and maximum flow of each flow meter. In the tests three different water tempera-tures and three different installations were investigated. Water temperatures of 20 °C, 50 °C and 70 °C were used. These temperatures are representative for district heating applications. The installations tested involved flow meters mounted with long straight pipes both up-and down-stream representing ideal conditions, a single elbow and a double elbow out of plane both generating disturbed flow profiles. All set-ups are in accordance with the flow meter specifications. The results demonstrate that both the change in temperature and the disturbed flow profiles introduce errors in the flow measurements. The change from 20 °C to 50 °C and 70 °C can cause a shift in meter performance larger than the specified maximum permissible error. Compared with the ideal installation the installations generating disturbed flow profiles cause errors up to more than 2 %. The errors due to temperature and installation effects have a bias to add when combined. This might lead to even larger errors.
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| 5. |
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| 6. |
- Derhamy, Hasan
(författare)
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Architectural Design Principles For Industrial Internet of Things
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As society has progressed through periods of evolution and revolution, technology hasplayed a key role as an enabler. In the same manner that mechanical machines of the1800’s drove the industrial revolution, now digitalized machines are driving another one.With this recognition of a fourth industrial revolution, the Industry 4.0 initiative wasfounded. One of the drivers of Industry 4.0 is the Industrial Internet of Things (IIoT).The IIoT is a consequence of widely present computing ubiquity and interconnected-ness. Software has become a crucial tool of almost all industries from bakeries and arts to manufacturing facilities and banking. Programming is now a required competenceand used by a variety of professions. It is not only about algorithm development, it has become more about engineering and integrating existing designs and tools. This impacts the way software is architected and drives a large body of research in the area.Software solutions are becoming more distributed, not only over multiple processes, but over heterogeneous hardware and business domains. Computing platforms could bemobile or geographically separated over large distances, exposing the solutions to network disturbances, performance degradation and security vulnerabilities.Hence, IIoT introduces complexity on a scale previously unseen in the software in-dustry. Software architecture must accommodate these heterogeneous domains and com-petencies and handle the increasing levels of complexity.This thesis proposes an architectural style for designing IIoT software architectures.The popular Service Oriented Architecture (SOA) style is not sufficient to define a com-plete architecture for IIoT applications. SOA fundamental principles are defined as loose coupling, lookup and late binding. The proposed architecture style extends these SOA principles with autonomy, specialization, data at its source and first person perspective. It preserves the benefits of SOA that models functionalities as reusable services with standardized interfaces. Thus, the proposed style helps to capture the heterogeneity of IIoT (e.g. systems, capabilities, domains, competencies etc.), while handling challenges imposed by it. The style also captures resource constraints of IIoT platforms; distri-bution of application logic across IIoT; dependence between services within IIoT; and presentation of the solution in various stakeholder perspectives.The IIoT generates large amounts of data that is subsequently stored, analysed, archived and eventually fed back into the product life cycle. Centralization of data has well known challenges. This thesis proposes a method of information extraction based on the principle of data at its source. Such data preserves implicit context, reducing the burden of semantic data within the system. Desired information is expressed through dynamic (runtime) queries. Using the queries, a path is created to retrieve the requested data. It alleviates the need for data to be stored in intermediary nodes; data remains atthe source. Thus, IIoT applications extract information and present it to requesting sys-tems without redundant source related context. This helps with issues of data ownership, access control and stale data.Another IIoT challenge tackled in this work is decentralization of Manufacturing Execution System (MES). It is motivated by a need to mitigate the impact of vulnerable shared networks on the factory floor; and by business requirements to reduce dependence on local factory infrastructure. This thesis explores a solution where functions of MES are distributed to the workstations that enables them to operate autonomously. Such autonomous workstations utilize the proposed Intelligent Product, Workflow Managerand Workflow Executor systems. Thus, MES can be decentralized to edge nodes as envisioned by Industry 4.0.
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| 7. |
- Derhamy, Hasan, et al.
(författare)
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System of System Composition based on Decentralized Service Oriented Architecture
- 2019
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Ingår i: IEEE Systems Journal. - : IEEE. - 1932-8184 .- 1937-9234. ; 13:4, s. 3675-3686
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Tidskriftsartikel (refereegranskat)abstract
- As society has progressed through periods of evolution and revolution, technology has played a key role as an enabler. In the same manner, mechanical machines of the 1800s drove the industrial revolution, now digitalized machines are driving another industrial revolution. Manufacturers are increasing the digital footprint on the factory floor. It is challenging to harness the vast amounts of data generated, stored, analyzed, archived, and returned. Data centralization has several well-known challenges, such as collection bottlenecks, secure retrieval, single point of failure, and data scheme fragility as data heterogeneity increases. This paper proposes a method of information distribution based on the principle of data at its source . It proposes that contextual data be used at runtime through the creation of dynamic queries that build compositions of different systems. Such system of systems (SoS) compositions handle the flow of data across its life cycle and present it as information to the initiating system. The proposal starts by creating a graph model of the Arrowhead framework. Then, building on the graph model, the query-based approach for specifying, validating, and forming the SoS is proposed. The proposed graph model allows for unambiguous description of systems and their interrelations, including security relations. The proposed composer operates on the edge computing hardware and gives the production floor the ability to extract information without impacting the overall operation of the factory.
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| 8. |
- Johansson, Jonny, et al.
(författare)
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Simulation of absolute amplitudes of ultrasound signals using equivalent circuits
- 2007
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Ingår i: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control. - 0885-3010 .- 1525-8955. ; 54:10, s. 1977-1983
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Tidskriftsartikel (refereegranskat)abstract
- Equivalent circuits for piezoelectric devices and ultrasonic transmission media can be used to cosimulate electronics and ultrasound parts in simulators originally intended for electronics. To achieve efficient systemlevel optimization, it is important to simulate correct, absolute amplitude of the ultrasound signal in the system, as this determines the requirements on the electronics regarding dynamic range, circuit noise, and power consumption.This paper presents methods to achieve correct, absolute amplitude of an ultrasound signal in a simulation of a pulse-echo system using equivalent circuits. This is achieved by taking into consideration loss due to diffraction and the effect of the cable that connects the electronics and the piezoelectric transducer. The conductive loss in the transmission line that models the propagation media of the ultrasound pulse is used to model the loss due to diffraction.Results show that the simulated amplitude of the echo follows measured values well in both near and far fields, with an offset of about 10%. The use of a coaxial cable introduces inductance and capacitance that affect the amplitude of a received echo. Amplitude variations of 60% were observed when the cable length was varied between 0.07 m and 2.3 m, with simulations predicting similar variations. The high precision in the achieved results show that electronic design and system optimization can rely on system simulations alone. This will simplify the development of integrated electronics aimed at ultrasound systems.
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| 9. |
- Lindström, John, et al.
(författare)
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Impact on production systems from recent and emerging complex business models: Explicit and tacit knowledge required
- 2015
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 38, s. 210-215
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Tidskriftsartikel (refereegranskat)abstract
- The paper addresses, based on an empirical study, what impact the use of recent complex business models, in particular, Functional Products, may have on production systems in terms of the explicit and tacit knowledge that is required. Requirements for new knowledge currently lacking or in the process of being acquired have been of specific interest for the study. The study focuses on the customer side, involving both manufacturing and process industry companies. A set of explicit and tacit knowledge aspects has been identified. The current set of knowledge aspects found during the literature review has largely been corroborated and the new specific knowledge identified is highlighted.
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| 10. |
- Martinsson, Pär-Erik, et al.
(författare)
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Ultrasonic measurements of molecular relaxation in ethane and carbon monoxide
- 2002
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Ingår i: Proceedings. - Piscataway, NJ : IEEE Communications Society. - 0780375823 ; , s. 511-516
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Konferensbidrag (refereegranskat)abstract
- This paper describes how molecular relaxation can be measured using ultrasound. The velocity and absorption of sound varies with frequency due to molecular relaxation. By measuring these variation the relaxation strength and the effective relaxation time for singular relaxations can be calculated. This paper describes initial measurements performed in order to survey the sound properties in gases both experimentally and theoretically.
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