| 1. |
- Berezovskyi, Andrii, 1991-, et al.
(författare)
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Efficient state update exchange in a CPS environment for linked data-based digital twins
- 2019
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Ingår i: IEEE International Conference on Industrial Informatics (INDIN). - : Institute of Electrical and Electronics Engineers Inc.. - 9781728129273 ; , s. 983-989
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Konferensbidrag (refereegranskat)abstract
- This paper addresses the problem of reducing the number of messages needed to exchange state updates between the Cyber-Physical System (CPS) components that integrate with the rest of the CPS through Digital Twins in order to maintain uniform communication interface and carry out their tasks correctly and safely. The main contribution is a proposed architecture and the discussion of its suitability to support correct execution of complex tasks across the CPS. A new State Event Filtering component is presented to provide event-based communication among Digital Twins that are based on the Linked Data principles while keeping the fan-out limited to ensure the scalability of the architecture.
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| 2. |
- Berezovskyi, Andrii, 1991-, et al.
(författare)
-
Improving lifecycle query in integrated toolchains using linked data and MQTT-based data warehousing
- 2017
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Konferensbidrag (refereegranskat)abstract
- The development of increasingly complex IoT systems requires large engineering environments. These environments generally consist of tools from different vendors and are not necessarily integrated well with each other. In order to automate various analyses, queries across resources from multiple tools have to be executed in parallel to the engineering activities. In this paper, we identify the necessary requirements on such a query capability and evaluate different architectures according to these requirements. We propose an improved lifecycle query architecture, which builds upon the existing Tracked Resource Set (TRS) protocol, and complements it with the MQTT messaging protocol in order to allow the data in the warehouse to be kept updated in real-time. As part of the case study focusing on the development of an IoT automated warehouse, this architecture was implemented for a toolchain integrated using RESTful microservices and linked data.
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| 3. |
- Berezovskyi, Andrii, 1991-, et al.
(författare)
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Integrating systems of systems with a federation of rule engines
- 2024
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Ingår i: Journal of Industrial Information Integration. - : Elsevier BV. - 2467-964X .- 2452-414X. ; 38
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Tidskriftsartikel (refereegranskat)abstract
- Systems of Systems (SoSs) integrate many critical systems our society relies on. In designing individual systems, stakeholders use bespoke protocols, custom information models, and proprietary components with limited computational resources from various vendors. We present a reference architecture that allows multiple stakeholders to carry out a flexible integration without giving up control to a single entity in the presence of the aforementioned limitations. Our architecture relies on rule engines and graph data model to integrated systems flexibly even when black-box components are used. At the same time, a federation of the rule engines allows each stakeholder to retain control over the rules that reflect their policies. We also rely on a common information model based on ontologies to account for the information model mismatch and reduce the duplication of integration efforts. Moving rule execution to the standalone rule engines allows deployment in resource-constrained and proprietary environments. A uniform application programming interface (API) is used to integrate rule engines across systems as well as components within each system with a respective rule engine. We also present a novel algorithm to determine dependencies across rules deployed in different rule engines within the federation. This allows domain experts to develop rules as usual without having to deal with the distributed aspect of the system. We also present a proof of the sufficient condition to ensure all necessary notifications will be sent to ensure correct rule activation across different rule engines. Compared to other systems involving distributed rules, the proposed architecture is well-suited for the integration of transactional workloads commonly found in enterprises. The qualitative evaluation based on the Architecture Tradeoff Analysis Method (ATAM), applied to a telecommunications use case, shows that the architecture possesses the “interoperability”, “modifiability”, and the “functional completeness” quality attributes with a trade-off around rule expressiveness. The quantitative evaluation demonstrates speedup over the single-node setup in most scenarios except in case of highly optimized rules and a poor network performance simultaneously (tr<10ms, tn=100ms).
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| 4. |
- Berezovskyi, Andrii, 1991-, et al.
(författare)
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Linked Data Architecture for Plan Execution in Distributed CPS
- 2019
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Ingår i: 2019 IEEE International Conference on Industrial Technology (IEEE ICIT). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538663769 ; , s. 1393-1399
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Konferensbidrag (refereegranskat)abstract
- Future cyber-physical systems (CPS) require their components to perform autonomously. To do that safely and efficiently, CPS components will need access to the global state of the whole CPS. These components will require near real-time updates to a subset of the global state to react to changes in the environment. A particular challenge is to monitor state updates from the distributed CPS components: one needs to ensure that only states consistent with the PDDL plan execution semantics can be observed within the system. In order to guarantee that, a component to monitor plan execution is proposed. Microservices based on Linked Data technologies are used to provide a uniform way to access component states, represented as Resource Description Framework (RDF) resources. To ensure the correct ordering of state updates, we present an extension of the OASIS OSLC TRS protocol. Specifically, we strengthen the ordering guarantees of state change events and introduce inlining of the state with the events to prevent state mismatch at the dereferencing stage.
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| 5. |
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| 6. |
- El-khoury, Jad, 1975-, et al.
(författare)
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A Model-Driven Engineering Approach to Software Tool Interoperability based on Linked Data
- 2016
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Ingår i: International Journal on Advances in Software. - : ThinkMind. - 1942-2628. ; 9:3 & 4, s. 248-259
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Tidskriftsartikel (refereegranskat)abstract
- Product development environments need to shift from the current document-based, towards an informationbased focus, in which the information from the various engineering software tools is well integrated and made digitally accessible throughout the development lifecycle. To meet this need, a Linked Data approach to software tool interoperability is being adopted, specifically through the Open Services for Lifecycle Collaboration (OSLC) interoperability standard. In this paper, we present a model-driven engineering approach to toolchain development that targets the specific challenges faced when adopting the technologies, standards and paradigm expected of Linked Data and the OSLC standard. We propose an integrated set of modelling views that supports the early specification phases of toolchain development, as well as its detailed design and implementation phases. An open-source modelling tool was developed to realize the proposed modelling views. The tool includes a code generator that synthesizes a toolchain model into almost-complete OSLC-compliant code. The study is based on a case study of developing a federated OSLC-based toolchain for the development environment at the truck manufacturer Scania AB.
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| 7. |
- El-Khoury, Jad, 1975-
(författare)
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A Model Management and Integration Platform for Mechatronics Product Development
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mechatronics development requires the close collaboration of various specialist teams and engineering disciplines. Developers from the different disciplines use domain-specific tools to specify and analyse the system of interest. This leads to different views of the system, each targeting a specific audience, using that audience’s familiar language, and concentrating on that audience’s concerns. Successful system development requires that the views of all developers produced by the different tools are well integrated into a whole, reducing any risks of inconsistencies and conflicts in the design information specified. This thesis discusses techniques of managing and integrating the views from various disciplines, taking better advantage of multidisciplinary, model-based, development. A Model Data Management (MDM) platform that generically manages models from the various domain-specific tools used in development is presented. The platform is viewed as a unification of the management functionalities typically provided by the discipline-specific PDM and SCM systems. The unification is achieved by unifying the kind of objects it manages – models. View integration is considered as an integral functionality of this platform. In demonstrating the platform’s feasibility, a generic version management functionality of models is implemented. In addition, model integration is investigated for the allocation of system functions onto the implementing hardware architecture. The proposed approach promotes the independent development of the views, allowing developers from each discipline to work concurrently, yet ensuring the completeness, correctness and analysis of any inter-view design decisions made. The prototype MDM platform builds on existing technologies from each of the mechanical and software disciplines. The proposed MDM system is built based on a configurable PDM system, given its maturity and ability to manage model contents appropriately. At the same time, the version control functionality borrows ideas from the fine-grained version control algorithms in the software discipline. The platform is argued to be feasible given the move towards model-based development in software engineering, bringing the discipline’s needs closer to those of the hardware discipline. This leads the way for an easier and more effective integrated management platform satisfying the needs of both disciplines using a common set of mechanisms.
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| 8. |
- El-khoury, Jad, 1975-, et al.
(författare)
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A Roadmap Towards Integrated CPS Development Environments
- 2013
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Konferensbidrag (refereegranskat)abstract
- Cyber Physical System (CPS) development is highly heterogeneous, involving many stakeholders, each of which interacts with its development artifacts through a variety of tools, and within several engineering processes. Successful CPS development requires these tools to be well-integrated into a Development Environment (DE) in order to support its many stakeholders and processes. In this paper we identify the main challenges facing DE development for CPSs, and presents a roadmap to meet these challenges. We here take the position that focus should be redirected from trying to achieve a single, one-size-fits-all solution to such a heterogeneous problem. Instead, focus should be placed on supporting the development of highly-customized DEs, which readily can be applied to industrial development. Such a highly-customized DE should fit the needs of a particular development organization, while at the same time taking advantage of relevant standardization efforts.
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| 9. |
- El-khoury, Jad, 1975-
(författare)
-
An Analysis of the OASIS OSLC Integration Standard, for a Cross-disciplinary Integrated Development Environment : Analysis of market penetration, performance and prospects
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- OASIS OSLC is a standard that targets the integration of engineering software applications. Its approach promotes loose coupling, in which each application autonomously manages its own product data, while providing RESTful web services through which other applications can interact.This report aims to analyse the suitability of OSLC as an overarching integration mechanism for the complete set of engineering activities of Cyber Physical Systems (CPS) development.To achieve this, a review of the current state of the OASIS OSLC integration standard is provided in terms of its market penetration in commercial applications, its capabilities, and the architectural qualities of OSLC-based solutions. This review is based on a survey of commercial software applications that provide some support for OSLC capabilities.
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| 10. |
- El-khoury, Jad, 1975-, et al.
(författare)
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An industrial evaluation of data access techniques for the interoperability of engineering software tools
- 2019
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Ingår i: Journal of Industrial Information Integration. - : ELSEVIER. - 2467-964X .- 2452-414X. ; 15, s. 58-68
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Tidskriftsartikel (refereegranskat)abstract
- New industrial initiatives such as Industrie 4.0 rely on digital end-to-end engineering across the entire product lifecycle, which in turn depends on the ability of the supporting software tools to interoperate. A tool interoperability approach based on Linked Data, and the OASIS OSLC standard, has the potential to provide such integration, where each software tool can expose its information and services to other tools using the web as a common technology base. In this paper, we report on our negative findings when attempting to use existing ontology-based Linked Data access techniques to expose and manipulate the structured content managed in engineering tools. Such techniques typically target the Data Access Layer (DAL) of a tool to access and manipulate its content, with the assumption that sufficient information and control is available within this layer to automate the process. Based on a case study with the truck manufacturer Scania CV AB, our study finds that an engineering tool controls its artefacts using business logic that is not necessarily reflected at the data layer. This renders such ontology-based access techniques inadequate. Instead we propose an alternative Linked Data extraction architecture that can mitigate the identified shortcomings. While less automated compared to the existing solutions, the proposed architecture is realised as a standalone library that can still facilitate the extraction process.
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