164 research outputs found
Exploiting Process Algebras and BPM Techniques for Guaranteeing Success of Distributed Activities
The communications and collaborations among activities, pro-
cesses, or systems, in general, are the base of complex sys-
tems defined as distributed systems. Given the increasing
complexity of their structure, interactions, and functionali-
ties, many research areas are interested in providing mod-
elling techniques and verification capabilities to guarantee
their correctness and satisfaction of properties. In particular,
the formal methods community provides robust verification
techniques to prove system properties. However, most ap-
proaches rely on manually designed formal models, making
the analysis process challenging because it requires an expert
in the field. On the other hand, the BPM community pro-
vides a widely used graphical notation (i.e., BPMN) to design
internal behaviour and interactions of complex distributed
systems that can be enhanced with additional features (e.g.,
privacy technologies). Furthermore, BPM uses process min-
ing techniques to automatically discover these models from
events observation. However, verifying properties and ex-
pected behaviour, especially in collaborations, still needs a
solid methodology.
This thesis aims at exploiting the features of the formal meth-
ods and BPM communities to provide approaches that en-
able formal verification over distributed systems. In this con-
text, we propose two approaches. The modelling-based ap-
proach starts from BPMN models and produces process al-
gebra specifications to enable formal verification of system
properties, including privacy-related ones. The process mining-
based approach starts from logs observations to automati-
xv
cally generate process algebra specifications to enable veri-
fication capabilities
Formal Methods for Autonomous Systems
Formal methods refer to rigorous, mathematical approaches to system
development and have played a key role in establishing the correctness of
safety-critical systems. The main building blocks of formal methods are models
and specifications, which are analogous to behaviors and requirements in system
design and give us the means to verify and synthesize system behaviors with
formal guarantees.
This monograph provides a survey of the current state of the art on
applications of formal methods in the autonomous systems domain. We consider
correct-by-construction synthesis under various formulations, including closed
systems, reactive, and probabilistic settings. Beyond synthesizing systems in
known environments, we address the concept of uncertainty and bound the
behavior of systems that employ learning using formal methods. Further, we
examine the synthesis of systems with monitoring, a mitigation technique for
ensuring that once a system deviates from expected behavior, it knows a way of
returning to normalcy. We also show how to overcome some limitations of formal
methods themselves with learning. We conclude with future directions for formal
methods in reinforcement learning, uncertainty, privacy, explainability of
formal methods, and regulation and certification
Computer Aided Verification
This open access two-volume set LNCS 13371 and 13372 constitutes the refereed proceedings of the 34rd International Conference on Computer Aided Verification, CAV 2022, which was held in Haifa, Israel, in August 2022. The 40 full papers presented together with 9 tool papers and 2 case studies were carefully reviewed and selected from 209 submissions. The papers were organized in the following topical sections: Part I: Invited papers; formal methods for probabilistic programs; formal methods for neural networks; software Verification and model checking; hyperproperties and security; formal methods for hardware, cyber-physical, and hybrid systems. Part II: Probabilistic techniques; automata and logic; deductive verification and decision procedures; machine learning; synthesis and concurrency. This is an open access book
Modelling and optimizing socio-technical operations in healthcare using the FRAM and reinforcement learning
This PhD research work is intended to model, analyze, and optimize socio-technical
operations in healthcare using a systemic approach and reinforcement learning. An
extensive literature review is presented, and the main knowledge gaps related to
modelling and optimizing socio-technical operations in healthcare are clearly outlined
and addressed in this research work.
Introduction: Hospital to home transition processes of frail older adults include a set
of actions for frail people who are discharged from hospital to their home in the
community. The transition process exhibits dynamic interactions between technology,
humans, organizations, and the environment. The non-linear dependencies among
these influential parameters complicate the understanding of the transition process
and the mechanism of modelling its operations.
Objectives: The objectives of this research work are (a) To identify the strengths and
shortcomings of the FRAM in modelling complex socio-technical systems; (b) To
develop a comprehensive model of the hospital-to-home transition process for frail
patients; (c) To capture and visualize different characteristics of variability in the
transition process; (d) To monitor frail patients’ transitions from hospital to home; (e)
To identify challenges of the transition process; and (f) To explore functional
pathways to identify transition processes with the highest quality of care and services
for frail older people.
Methodology: This research work uses the Functional Resonance Analysis Method
(FRAM) to study and model the complexity of the transition process. A
complementary tool for the FRAM (DynaFRAM) is also used to characterize
functional and system variability in order to identify the challenges of successful
transition processes. Additionally, this research employs the reinforcement learning
technique to explore the functional transition model generated by the FRAM to
investigate a basic method to optimize the transition process for frail people.
Results and discussion: The results of this research work show that FRAM-generated
models can serve as a basis in further analyses regarding complexity, safety, and risk
management. The results also indicate that the DynaFRAM tool helps monitor
patients’ hospital-to-home transitions and characterize different types of variability in
functional and system outputs. A comprehensive modelÂą of the transition process was
built using the FRAM. It includes a library of 38 functions classified in five
categories. The outcomes of using the DynaFRAM for monitoring patients’ transitions
revealed functions with significant variability. The variability observed in the outputs
of these functions could be challenging as the variability of a function can reinforce
the variability of down-stream functions and affect the performance of the entire
transition process. Finally, the results of coupling the FRAM to reinforcement
learning help evaluate the system performance in terms of accumulated action value
achieved by an artificial agent during functional pathways.
Conclusion: In light of the FRAM, the complexity of the transition process can be
visualized and understood better. The application of the DynaFRAM helps enhance
the situation awareness of frail patients through providing healthcare providers with
where a patient is and what they need during the transition process. Coupling the
FRAM and reinforcement learning would benefit the healthcare system by providing
guidance on how to provide the best care to frail patients in the light of various
circumstances.
ÂąThe transition model is called comprehensive as it includes the perspectives of healthcare
professionals, patients, and caregivers. It also involves pre-discharge and post-discharge processes
Proceedings of the 22nd Conference on Formal Methods in Computer-Aided Design – FMCAD 2022
The Conference on Formal Methods in Computer-Aided Design (FMCAD) is an annual conference on the theory and applications of formal methods in hardware and system verification. FMCAD provides a leading forum to researchers in academia and industry for presenting and discussing groundbreaking methods, technologies, theoretical results, and tools for reasoning formally about computing systems. FMCAD covers formal aspects of computer-aided system design including verification, specification, synthesis, and testing
Agents and Robots for Reliable Engineered Autonomy
This book contains the contributions of the Special Issue entitled "Agents and Robots for Reliable Engineered Autonomy". The Special Issue was based on the successful first edition of the "Workshop on Agents and Robots for reliable Engineered Autonomy" (AREA 2020), co-located with the 24th European Conference on Artificial Intelligence (ECAI 2020). The aim was to bring together researchers from autonomous agents, as well as software engineering and robotics communities, as combining knowledge from these three research areas may lead to innovative approaches that solve complex problems related to the verification and validation of autonomous robotic systems
A Survey of Practical Formal Methods for Security
In today's world, critical infrastructure is often controlled by computing systems. This introduces new risks for cyber attacks, which can compromise the security and disrupt the functionality of these systems. It is therefore necessary to build such systems with strong guarantees of resiliency against cyber attacks. One way to achieve this level of assurance is using formal verification, which provides proofs of system compliance with desired cyber security properties. The use of Formal Methods (FM) in aspects of cyber security and safety-critical systems are reviewed in this article. We split FM into the three main classes: theorem proving, model checking, and lightweight FM. To allow the different uses of FM to be compared, we define a common set of terms. We further develop categories based on the type of computing system FM are applied in. Solutions in each class and category are presented, discussed, compared, and summarised. We describe historical highlights and developments and present a state-of-the-art review in the area of FM in cyber security. This review is presented from the point of view of FM practitioners and researchers, commenting on the trends in each of the classes and categories. This is achieved by considering all types of FM, several types of security and safety-critical systems, and by structuring the taxonomy accordingly. The article hence provides a comprehensive overview of FM and techniques available to system designers of security-critical systems, simplifying the process of choosing the right tool for the task. The article concludes by summarising the discussion of the review, focusing on best practices, challenges, general future trends, and directions of research within this field
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