443,060 research outputs found
A Vision of Collaborative Verification-Driven Engineering of Hybrid Systems
Abstract. Hybrid systems with both discrete and continuous dynamics are an important model for real-world physical systems. The key challenge is how to ensure their correct functioning w.r.t. safety requirements. Promising techniques to ensure safety seem to be model-driven engineering to develop hybrid systems in a well-defined and traceable manner, and formal verification to prove their correctness. Their combination forms the vision of verification-driven engineering. Despite the remarkable progress in automating formal verification of hybrid systems, the construction of proofs of complex systems often requires significant human guidance, since hybrid systems verification tools solve undecidable problems. It is thus not uncommon for verification teams to consist of many players with diverse expertise. This paper introduces a verification-driven engineering toolset that extends our previous work on hybrid and arithmetic verification with tools for (i) modeling hybrid systems, (ii) exchanging and comparing models and proofs, and (iii) managing verification tasks. This toolset makes it easier to tackle large-scale verification tasks.
Online Verification of Deep Neural Networks under Domain or Weight Shift
Although neural networks are widely used, it remains challenging to formally
verify the safety and robustness of neural networks in real-world applications.
Existing methods are designed to verify the network before use, which is
limited to relatively simple specifications and fixed networks. These methods
are not ready to be applied to real-world problems with complex and/or
dynamically changing specifications and networks. To effectively handle
dynamically changing specifications and networks, the verification needs to be
performed online when these changes take place. However, it is still
challenging to run existing verification algorithms online. Our key insight is
that we can leverage the temporal dependencies of these changes to accelerate
the verification process, e.g., by warm starting new online verification using
previous verified results. This paper establishes a novel framework for
scalable online verification to solve real-world verification problems with
dynamically changing specifications and/or networks, known as domain shift and
weight shift respectively. We propose three types of techniques (branch
management, perturbation tolerance analysis, and incremental computation) to
accelerate the online verification of deep neural networks. Experiment results
show that our online verification algorithm is up to two orders of magnitude
faster than existing verification algorithms, and thus can scale to real-world
applications
What did I really vote for? On the usability of verifiable e-voting schemes
E-voting has been embraced by a number of countries, delivering benefits in terms of efficiency and accessibility. End-to-end verifiable e-voting schemes facilitate verification of the integrity of individual votes during the election process. In particular, methods for cast-as-intended verification enable voters to confirm that their cast votes have not been manipulated by the voting client. A well-known technique for effecting cast-as-intended verification is the Benaloh Challenge. The usability of this challenge is crucial because voters have to be actively engaged in the verification process. In this paper, we report on a usability evaluation of three different approaches of the Benaloh Challenge in the remote e-voting context. We performed a comparative user study with 95 participants. We conclude with a recommendation for which approaches should be provided to afford verification in real-world elections and suggest usability improvements
Collaborative Verification-Driven Engineering of Hybrid Systems
Hybrid systems with both discrete and continuous dynamics are an important
model for real-world cyber-physical systems. The key challenge is to ensure
their correct functioning w.r.t. safety requirements. Promising techniques to
ensure safety seem to be model-driven engineering to develop hybrid systems in
a well-defined and traceable manner, and formal verification to prove their
correctness. Their combination forms the vision of verification-driven
engineering. Often, hybrid systems are rather complex in that they require
expertise from many domains (e.g., robotics, control systems, computer science,
software engineering, and mechanical engineering). Moreover, despite the
remarkable progress in automating formal verification of hybrid systems, the
construction of proofs of complex systems often requires nontrivial human
guidance, since hybrid systems verification tools solve undecidable problems.
It is, thus, not uncommon for development and verification teams to consist of
many players with diverse expertise. This paper introduces a
verification-driven engineering toolset that extends our previous work on
hybrid and arithmetic verification with tools for (i) graphical (UML) and
textual modeling of hybrid systems, (ii) exchanging and comparing models and
proofs, and (iii) managing verification tasks. This toolset makes it easier to
tackle large-scale verification tasks
Metamorphoses of ONAV console operations: From prototype to real time application
The ONAV (Onboard Navigation) Expert System is being developed as a real time console assistant to the ONAV flight controller for use in the Mission Control Center at the Johnson Space Center. Currently the entry and rendezvous systems are in verification, and the ascent is being prototyped. To arrive at this stage, from a prototype to real world application, the ONAV project has had to deal with not only AI issues but operating environment issues. The AI issues included the maturity of AI languages and the debugging tools, what is verification, and availability, stability, and the size of the expert pool. The environmental issues included real time data acquisition, hardware stability, and how to achieve acceptance by users and management
Biometric system verification close to "real world" conditions
The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-04391-8_31Proceedings of Joint COST 2101 and 2102 International Conference, BioID_MultiComm 2009, Madrid, Spain.In this paper we present an autonomous biometric device developed in the framework of a national project. This system is able to capture speech, hand-geometry, online signature and face, and can open a door when the user is positively verified. Nevertheless the main purpose is to acquire a database without supervision (normal databases are collected in the presence of a supervisor that tells you what to do in front of the device, which is an unrealistic situation). This system will permit us to explain the main differences between what we call "real conditions" as opposed to "laboratory conditions".This work has been supported by FEDER and MEC, TEC2006-13141-C03/TCM, and COST-2102
An experimental Study using ACSL and Frama-C to formulate and verify Low-Level Requirements from a DO-178C compliant Avionics Project
Safety critical avionics software is a natural application area for formal
verification. This is reflected in the formal method's inclusion into the
certification guideline DO-178C and its formal methods supplement DO-333.
Airbus and Dassault-Aviation, for example, have conducted studies in using
formal verification. A large German national research project, Verisoft XT,
also examined the application of formal methods in the avionics domain.
However, formal methods are not yet mainstream, and it is questionable if
formal verification, especially formal deduction, can be integrated into the
software development processes of a resource constrained small or medium
enterprise (SME). ESG, a Munich based medium sized company, has conducted a
small experimental study on the application of formal verification on a small
portion of a real avionics project. The low level specification of a software
function was formalized with ACSL, and the corresponding source code was
partially verified using Frama-C and the WP plugin, with Alt-Ergo as automated
prover.
We established a couple of criteria which a method should meet to be fit for
purpose for industrial use in SME, and evaluated these criteria with the
experience gathered by using ACSL with Frama-C on a real world example. The
paper reports on the results of this study but also highlights some issues
regarding the method in general which, in our view, will typically arise when
using the method in the domain of embedded real-time programming.Comment: In Proceedings F-IDE 2015, arXiv:1508.0338
Abstraction of Elementary Hybrid Systems by Variable Transformation
Elementary hybrid systems (EHSs) are those hybrid systems (HSs) containing
elementary functions such as exp, ln, sin, cos, etc. EHSs are very common in
practice, especially in safety-critical domains. Due to the non-polynomial
expressions which lead to undecidable arithmetic, verification of EHSs is very
hard. Existing approaches based on partition of state space or
over-approximation of reachable sets suffer from state explosion or inflation
of numerical errors. In this paper, we propose a symbolic abstraction approach
that reduces EHSs to polynomial hybrid systems (PHSs), by replacing all
non-polynomial terms with newly introduced variables. Thus the verification of
EHSs is reduced to the one of PHSs, enabling us to apply all the
well-established verification techniques and tools for PHSs to EHSs. In this
way, it is possible to avoid the limitations of many existing methods. We
illustrate the abstraction approach and its application in safety verification
of EHSs by several real world examples
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