The Digital Twin (DT) paradigm has been largely adopted for many smart systems in various domains. Due to the heterogeneous and distributed nature of the physical twins, these systems increasingly incorporate disparate security tools, especially those based on service-based AI/ML capabilities. That presents numerous challenges in achieving a comprehensive understanding of security analytics and explainability in security operations carried out by ML-based security services, which require continuous monitoring and optimization to remain effective. This paper aims to support security service integration and automated analyses with enhanced explainability in DTs. We introduce a novel framework that unifies runtime contexts to facilitate security services unification and operation interpretation in security orchestration. We define a workflow and provide necessary services for generating security reports across physical and logical layers. Leveraging a centralized knowledge service, we let security analysts incorporate domain knowledge in automating incident reasoning and security enforcement at the logical layer. We demonstrate our explainability framework on a DT of an Industry 4.0 toy factory with two ML-based security services detecting network anomalies. Our experiments show a significant reduction in manual effort for orchestrating security incident analysis and mitigation.

The new Industry 4.0 envisions a future for agile and effective integration of the physical operational technologies (OT) and the cyber information technologies (IT) as well as autonomous cooperation among them. However, the wide variety and heterogeneity of industrial systems and field devices -especially on the factory floor - increase integration complexity. To address these challenges, new technologies and concepts such as the Industrial Internet of Things (IIoT), Service-oriented Architecture (SoA), Semantic Technologies, Machine Learning and Artificial Intelligence are being introduced to the industrial environment. In this paper, we focus on how industrial automation systems and field devices can be integrated into the IIoT framework and coordinated to adapt to dynamic operating environment. Specifically, this paper proposed an interoperability solution that makes use of SoA and Semantic Technologies to achieve supervised coordination of IIoT application systems. To illustrate the potential of this approach, the Service-oriented Architecture-based Arrowhead Framework is used as the fundamental framework for the implementation of the approach.

Industrial cyber-physical systems are advancing rapidly along with the emergence of the fourth industrial revolution. It is, therefore, necessary to design and develop appropriate tools and frameworks that allow the migration/integration of legacy systems into the new Industry 4.0 environment. OPC-UA is one of the recommended technologies to enable communication and interoperability of digitalized assets in Industry 4.0. This paper proposes a solution to develop an OPC-UA interface for industrial systems for service-oriented architecture. With the use of the Arrowhead Framework - a cloud-based framework facilitating interoperability and integrability of Industrial Internet of Things - and Industry 4.0-compliant technologies, the authors describe the procedure of developing different application systems which dynamically produce and consume OPC-UA services within a local automation cloud.

Introducing semantics into the Internet of Things (IoT) has been attracting increasing attention from researchers and industrial practitioners. Semantic technologies have been used to enable interoperability as well as deal with the heterogeneity, massive scale, and dynamic nature of IoT resources. With the emergence of Industry 4.0, semantic technologies arise as a potential approach toward information modeling and dynamic reconfiguration of highly complex automation systems with high diversity of domains, protocols, tools or hardware platforms. Applying semantics into existing IoT frameworks requires a thorough understanding of the framework architectures as well as careful considerations of different semantic technologies. To support this process, we survey the literature on the contributions and usage of semantics in IoT. We find that semantics are mainly used to handle interoperable systems and heterogeneous standards. In this paper, we also propose procedures for applying semantics into IoT frameworks. Further, we present our idea of using semantics to enable dynamical orchestration of services within the Arrowhead Framework - an IoT framework that supports the development of industrial automation systems.

The automated task of locating the potential buggy files in a software project given a bug report is called bug localization. Bug localization helps developers focus on crucial files. However, the existing automated bug localization approaches face a key challenge, called lexical mismatch. Specifically, the terms used in bug reports to describe a bug are different from the terms and code tokens used in source files. To address that, we present a novel approach that uses deep neural network (DNN) in combination with rVSM, an information retrieval (IR) technique. rVSM collects the feature on the textual similarity between bug reports and source files. DNN is used to learn to relate the terms in bug reports to potentially different code tokens and terms in source files. Our empirical evaluation on real-world bug reports in the open-source projects shows that DNN and IR complement well to each other to achieve higher bug localization accuracy than individual models. Importantly, our new model, DNNLOC, with a combination of the features built from DNN, rVSM, and project's bug-fixing history, achieves higher accuracy than the state-of-the-art IR and machine learning techniques. In half of the cases, it iscorrect with just a single suggested file. In 66% of the time, acorrect buggy file is in the list of three suggested files. With 5 suggested files, it is correct in almost 70% of the cases.

Bug localization refers to the automated process of locating the potential buggy files for a given bug report. To help developers focus their attention to those files is crucial. Several existing automated approaches for bug localization from a bug report face a key challenge, called lexical mismatch, in which the terms used in bug reports to describe a bug are different from the terms and code tokens used in source files. This paper presents a novel approach that uses deep neural network (DNN) in combination with rVSM, an information retrieval (IR) technique. rVSM collects the feature on the textual similarity between bug reports and source files. DNN is used to learn to relate the terms in bug reports to potentially different code tokens and terms in source files and documentation if they appear frequently enough in the pairs of reports and buggy files. Our empirical evaluation on real-world projects shows that DNN and IR complement well to each other to achieve higher bug localization accuracy than individual models. Importantly, our new model, HyLoc, with a combination of the features built from DNN, rVSM, and project's bug-fixing history, achieves higher accuracy than the state-of-the-art IR and machine learning techniques. In half of the cases, it is correct with just a single suggested file. Two out of three cases, a correct buggy file is in the list of three suggested files.