About
101
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Introduction
Walter Terkaj currently works at the Institute of Industrial Intelligent Technologies and Systems for Advanced Manufacturing, Italian National Research Council.
Additional affiliations
January 2021 - present
June 2018 - December 2020
October 2015 - September 2018
Education
January 2006 - February 2009
September 1999 - October 2005
Publications
Publications (101)
Modelling, simulation and evaluation of manufacturing systems are relevant activities that may strongly impact on the competitiveness of production enterprises both during the design and the operational phases. This paper addresses the application of a semantic data model for virtual factories to support the design and the performance evaluation of...
Structured methodologies and tools for the tailored design of factories are more and more adopted by suppliers of manufacturing systems but usually discontinued after the design phase. The use of an ontology-based virtual factory, continuously synchronized with the real plant, is proposed to guarantee digital continuity and enable in situ simulatio...
The adoption of digital technologies in manufacturing enables intelligent dynamic control approaches, at the cost of increased design complexity. In this paper, ontologies and delta-lenses are exploited to enable multi-scale models of a manufacturing system to map digital models at different scales and let data flow according to the level of fideli...
Control policies significantly affect the performance of manufacturing systems, driving the need to assess their impact during both the design and operational phases. Performance evaluation tools can provide a relevant support, but their full exploitation is hindered by the difficulty of considering the huge variety of control decisions that are in...
Replying to requests for quotation in a fast and effective way is a key need for technology providers, in particular machine tool builders and system integrators. Digital factory technologies provide the opportunity of speeding up the generation of technical offers through the development of a digital twin of the system under study, thus enabling t...
Advances in digital factory technologies are offering great potential to innovate higher education, by enabling innovative learning approaches based on virtual laboratories that increase the involvement of students while delivering realistic experiences. This article introduces a framework for the development of virtual learning applications by add...
Forecasting future scenarios is an approach that enables companies, governments, and countries to interpolate the most important trends unfolding in a certain context to help tackle the uncertainties of a world that is changing ever more rapidly. The future outlook can be influenced by many different variables and it is reasonable to consider diffe...
The current digital transformation in manufacturing has a strong impact on the competencies needed by manufacturing companies. This leads to evolving requirements for digital training in industrial engineering courses. The concept of virtual labs in academic environments can be instrumental in teaching new digital skills through practical experienc...
Modern cyber-physical production systems provide advanced solutions to enhance factory throughput and efficiency. However, monitoring its behaviour and performance becomes challenging as the complexity of a manufacturing system increases. Artificial Intelligence (AI) provides techniques to manage not only decision-making tasks but also to support m...
The widespread adoption of digital technologies in factories has resulted in the generation of a vast amount of data, which has the potential to enhance efficiency and effectiveness in the manufacturing industry. However, collecting and analyzing these data require approaches and tools to design and operate complex digital models and infrastructure...
The representation of manufacturing resources plays a fundamental role in engineering modeling scenarios. These are characterized in a number of ways by taking into account their physical properties, capabilities, roles, etc. In this context, notions like capability, process, and functionality are used in different manners, hence it is not clear ho...
This paper aims to investigate the valorisation opportunities for the secondary metallurgy slag (SMS) as a by-product of electric arc furnace (EAF) steel production. The key stakeholders, their aim and possible configurations of the SMS value chain are identified considering the treatment unit owners and locations, pre-treatment and treatment proce...
Recent academic and industrial initiatives show an increasing interest in the use of foundational ontologies to support the development of domain-specific ontologies. Foundational ontologies guarantee formal and conceptual robustness, and at the same time support the integration of multiple domain-ontologies aligned to the same foundational ontolog...
With manufacturing going through the Industry 4.0 revolution, a vast amount of data and information exchange leads to an increase in complexity of digitized manufacturing systems. To tackle such complexity, one solution is to design and operate a digital twin model under different levels of abstraction, with different levels of detail, according to...
The Buffer Allocation Problem is a well-known optimization problem aiming at determining the optimal buffer sizes in a manufacturing system composed by various machines decoupled by buffers. This problem still has scientific relevance because of problem complexity and trade-off between conflicting goals. Moreover, it assumes industrial relevance in...
Digital modelling of manufacturing systems is experiencing a fast development, but it still shows significant limitations when considering integration and interoperability of enabling technologies. Indeed, there is still a lack of reference integrated workflows to perform the wide span of tasks, ranging from layout configuration and performance eva...
Higher education has to cope with current trends in digital technologies, in particular in the field of industrial engineering, where digital competencies are required more and more. Digital technologies, combined with serious gaming, offer new opportunities for teaching engineering in higher education, with a twofold objective: 1) offering student...
The growing relevance of digitalization in production requires the enhancement of human skills and competences in the field of Information and Communication Technology (ICT). Higher education has to cope with this need by providing the necessary ICT skills to future industrial engineers, so that they have a good understanding of the complexity of i...
The advent of industry 4.0 and the continuous digitalization of production ask for the enhancement of human skills and competences in the field of information and communication technology (ICT). Therefore, higher education has to keep pace with the global market needs for the necessary ICT skills and the overall understanding of the complexity of i...
Standards and ontologies for manufacturing understand resources differently. Because of this heterogeneity, misunderstandings arise concerning the basic features that characterize them. The purpose of the paper is to investigate how to ontologically model resources with the goal of facilitating the development of knowledge representation models for...
Mass customization requires frequent product changeovers thus leading to the need of manufacturing systems endowed with flexibility and reconfiguration capabilities, in order to be robust to changes in the production scenario. Therefore, manufacturing companies face a relevant risk when taking strategic decisions about which system resources should...
Standards and ontologies for manufacturing differently understand resources. Because of this heterogeneity, misunderstandings arise concerning the basic features that characterise them. The purpose of the paper is to shed some light on the ontology of resources to strive the development of computational models for manufacturing. In particular, we p...
Within the context of Industry 4.0, the presence of robotic systems inside the production plant is increasing, thus leading to the need for appropriate safety rules enhancing human-robot interaction. However, without a systematic approach, mapping all the possible scenarios becomes critical. This paper aims at laying the foundations for a unified s...
The Digital Twin is a representation of characteristics and behavior of a factory according to various levels of detail and the scope it addresses. Its full range of capabilities can be exploited when it is synchronized with the real world. Indeed, in this case, it can be used to mirror the real operating conditions for simulating the real-time beh...
This chapter deals with the central role of manufacturing in developed and developing countries, assessing how relevant it is from economic and social perspectives. The current international and Italian manufacturing contexts are analysed by highlighting the main criticalities and the impact of relevant global megatrends. Then, the main ongoing ind...
Mission-oriented policies have been proposed for research and innovation in the European manufacturing industry to address grand challenges while fostering economic growth and employment. A mission is required to have clear goals that can be demonstrated also to a wide public, therefore research and innovation infrastructures play a key role to cre...
This chapter investigates research priorities for factories of the future by adopting an approach based on mission-oriented policies to support manufacturing innovation. Missions are challenging from a scientific and technological point of view and, at the same time, are addressing problems and providing results that are understandable by common pe...
Flexibility and reconfigurability of production systems are typically exploited to cope with the changing production demand in terms of volume and variety. This work addresses the problem of enhancing the current flexibility of Flexible Manufacturing Systems (FMSs) by designing pallet configurations with zero-point modular fixtures. This class of e...
This book presents results relevant in the manufacturing research field, that are mainly aimed at closing the gap between the academic investigation and the industrial application, in collaboration with manufacturing companies. Several hardware and software prototypes represent the key outcome of the scientific contributions that can be grouped int...
More and more information and communication technologies originating from the web are introduced in industrial automation systems. The vision for future automation systems includes intelligent self-descriptive components, which exchange information and potentially reason by themselves through knowledge-assisted methods. Formal domain descriptions a...
The variability of the arrival and service processes has a strong impact on the performance of supply chain networks (SCNs), especially when the reverse flow to the manufacturer is considered. This paper proposes to use approximate analytical models to quickly evaluate the performance of SCN configurations during the design phase of the forward and...
Virtual manufacturing concepts have been adopted by most of the industrial companies, including the small and medium ones, to face the global competition and deal with the top challenges of manufacturing industry, i.e. improving the quality, reducing the delivery time and decreasing the costs. However, most of the virtual manufacturing methodologie...
The Digital Twin is a representation of characteristics and behavior of a component, product or system according to various levels of detail and the scope it addresses. Its full range of capabilities can be exploited when it is fully synchronized with the real world. Indeed, in this case, the digital twin can be used to support the whole product's...
Tool to automatically convert an EXPRESS schema into an OWL ontology, based on the content of the articles:
- Terkaj W, Sojic A (2015) Ontology-based Representation of IFC EXPRESS rules: an enhancement of the ifcOWL ontology.
- Pauwels P, Terkaj W (2016) EXPRESS to OWL for construction industry: Towards a recommendable and usable ifcOWL ontology
-...
The efficient instantiation of an OWL ontology still represents one of the barriers towards their extensive use in industrial applications not limited to the definition of more or less complex T-boxes. This paper presents the prototype no-ncommercial ontology-based software tool named OntoGui that can be employed in the management and instantiation...
Linked data and semantic web technologies are gaining impact and importance in the Architecture, Engineering, Construction and Facility Management (AEC/FM) industry. Whereas we have seen a strong technological shift with the emergence of Building Information Modeling (BIM) tools, this second technological shift to the exchange and management of bui...
This paper presents an ontology-based Virtual Factory tool to support the 3D design of factories. The official ifcOWL is the reference ontology that was adopted to develop the I/O software connector of the tool. The key advantage of the ontology interface is represented by the easy integration with other software tools that can either use the layou...
Building Information Modeling (BIM) and Semantic Web technologies are becoming more and more popular in the Architecture Engineering Construction (AEC) and Facilities Management (FM) industry to support information management , information exchange and data interoperability. One of the key integration gateways between BIM and Semantic Web is repres...
Significant efforts of the current manufacturing companies are devoted to the implementation of the full synchronization between the real world at the shop-floor level and its digital counterpart (so-called Digital Twin). Indeed, a true reflection of the real factory can be exploited to monitor and simulate the factory performance, allowing to adju...
Over the past few years, several suggestions have been made of how to convert an EXPRESS schema into an OWL ontology. The conversion from EXPRESS to OWL is of particular use to the architectural design and construction industry, because one of the key data models in this domain, namely the Industry Foundation Classes (IFC), is represented using the...
Data integration is one of the most crucial challenges for current manufacturing companies. Indeed, while the extended use of software tools generate more and more data about products, processes, and production resources, still this huge amount of data is represented using different formats and non-aligned structures. This issue is worsened by the...
This paper proposes a model-driven interoperability framework as a technical support of co-evolution strategy of product structure and production systems with a frugal innovation perspective. Based on the modularity concept, the role of this framework is to connect possible product modules managed in the Product Life cycle Management tool to all po...
Telemetry enables the collection of data from remote points to support monitoring, analysis and visualization. It is largely adopted in Formula One car racing, where streams of live data collected from hundreds of sensors installed on car components are transmitted to the pitwall to be used as input of real-time car performance simulations. The aim...
Background
The public health initiatives for obesity prevention are increasingly exploiting the advantages of smart technologies that can register various kinds of data related to physical, physiological, and behavioural conditions. Since individual features and habits vary among people, the design of appropriate intervention strategies for motivat...
Today's manufacturing systems need to be able to quickly adapt to customer demands, ranging from high volumes of mass production to high volumes of mass customization. Flexible Manufacturing Systems provide a high degree of flexibility to cope with these challenges. They consist of machine tools capable of executing a wide range of machining operat...
An increasing number of information management and information exchange applications in construction industry is relying on semantic web technologies or tools from the Linked Open Data (LOD) domain to support data interoperability, flexible data exchange, distributed data management and the development of reusable tools. These goals tend to be over...
Flexible Manufacturing Systems (FMSs) consist of machine tools capable of executing a wide range of machining operations relying on the fixtures to reference and block the parts. Hence, the constraints for their flexibility are shifted from the machines to the pallets. An interesting trend in the fixture market are zero-point fixture systems ground...
The design of a manufacturing systems is a complex and critical activity entailing decisions with an impact on a long time horizon and a major commitment of financial resources. Indeed, the modelling, simulation and evaluation of manufacturing systems are relevant activities both in the design and the operational phases of a factory. This paper gro...
The goal of this position paper is to introduce the research topics in engineering and the motivations for the application of semantic technologies. A group called Ontology Based Engineering – OBE has been created by the engineering community to share experiences in this field and the various challenges faced in using ontologies and related tools....
Over the past few years, several suggestions have been made of how to convert an EXPRESS schema into an OWL ontology. The conversion from EXPRESS to OWL is of particular use to architectural design and construction industry, because one of the key data models in architectural design and construction industry, namely the Industry Foundation Classes...
Semantic Web technologies are becoming more and more appealing to the community of the Industry Foundation Classes (IFC) users. The recent actions towards the development of an OWL version of the IFC schema (named ifcOWL) evidence the effort of facing the community request to specify IFC in an ontology language. This paper presents an enrichment of...
The problem of factory sustainability is commonly addressed by focusing on specific aspects related to products, processes or production resources, while the impact of the building and facilities is usually neglected even though it counts for 40% of the total world’s energy consumption. This paper presents a holistic framework based on an integrate...
There is an increasing interest in developing ontological versions of engineering standards. In general, this amounts to restating a given standard in some ontological language like OWL. We observe that without an ontological analysis of the standard, the conversion neither improves the clarity of the standard nor facilitates its coherent applicati...
Many recent research works have investigated the potential of an Ontology-based approach to support the standardization of the information in industrial scenarios. A key success factor in this regard is the effective and efficient reuse of existing knowledge sources because the building of new ones from scratch is an expensive and time-consuming ac...
The Industry Foundation Classes (IFC) is a standard providing an open vendor-independent file format and data model for data interoperability and exchange for Architecture/Engineering/Construction and Facility Management. Some works in the literature addressed the conversion of the standard to the Web Ontology Language, but there is still need of a...
In recent years, a real tsunami has flooded many human activities. Genomics, Astronomy, Particle Physics and Social Sciences are just a few examples of fields which have been intensively invaded by a massive amount of data coming from simulation, experiments or exploration. This huge pile of data requires a new way to deal with, a real paradigmatic...
In this paper we outline the general framework of the ontology that captures the obesity-related features of teenagers. We present our particular choices regarding the ontology-structure, which should be capable of capturing (1) multiple perspectives used to describe an adolescent and (2) reasoning about the individual changes during the time. In t...
The traditional production planning model based upon a deterministic approach is well described in the literature. Due to the uncertain nature of manufacturing processes, such model can however incorrectly represent actual situations on the shop floor. This study develops a mathematical modeling framework for generating production plans in a multi-...
The world's energy consumption has doubled over the past 40 years and it is estimated that one-third comes from industry. Therefore, an increase of the efficiency in energy use in industries would greatly benefit the sustainability of the factories and consequently of the whole environment and society. A factory is a complex entity constituted by p...
This paper presents the extension to an ontology-based data model supporting the design and performance evaluation of production systems. This extension aims to link the modeling of the spatial representation of physical objects with the characterization of their states and behavior. Furthermore, the formalization of the performance history of a pr...