Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Model Checking A Model Checker: A Code Contract Combined Approach, Jun Sun, Yang Liu, Bin Cheng
Model Checking A Model Checker: A Code Contract Combined Approach, Jun Sun, Yang Liu, Bin Cheng
Research Collection School Of Computing and Information Systems
Model checkers, like any complex software, are subject to bugs. Unlike ordinary software, model checkers are often used to verify safety critical systems. Their correctness is thus vital. Verifying model checkers is extremely challenging because they are always complicated in logic and highly optimized. In this work, we propose a code contract combined approach for checking model checkers and apply it to a home-grown model checker PAT. In this approach, we firstly embed programming contracts (i.e., pre/post-conditions and invariants) into its source code, which can capture correctness of model checking algorithms, underlying data structures, consistency between different model checking parameters, …
Model Checking Hierarchical Probabilistic Systems, Jun Sun, Songzheng Song, Yang Liu
Model Checking Hierarchical Probabilistic Systems, Jun Sun, Songzheng Song, Yang Liu
Research Collection School Of Computing and Information Systems
Probabilistic modeling is important for random distributed algorithms, bio-systems or decision processes. Probabilistic model checking is a systematic way of analyzing finite-state probabilistic models. Existing probabilistic model checkers have been designed for simple systems without hierarchy. In this paper, we extend the PAT toolkit to support probabilistic model checking of hierarchical complex systems. We propose to use PCSP#, a combination of Hoare’s CSP with data and probability, to model such systems. In addition to temporal logic, we allow complex safety properties to be specified by non-probabilistic PCSP# model. Validity of the properties (with probability) is established by refinement checking. Furthermore, …
Developing Model Checkers Using Pat, Yang Liu, Jun Sun, Jin Song Dong
Developing Model Checkers Using Pat, Yang Liu, Jun Sun, Jin Song Dong
Research Collection School Of Computing and Information Systems
During the last two decades, model checking has emerged as an effective system analysis technique complementary to simulation and testing. Many model checking algorithms and state space reduction techniques have been proposed. Although it is desirable to have dedicated model checkers for every language (or application domain), implementing one with effective reduction techniques is rather challenging. In this work, we present a generic and extensible framework PAT, which facilitates users to build customized model checkers. PAT provides a library of state-of-art model checking algorithms as well as support for customizing language syntax, semantics, state space reduction techniques, graphic user interfaces, …
A Verification System For Interval-Based Specification Languages, Chunqing Chen, Jin Song Dong, Jun Sun, Andrew P. Martin
A Verification System For Interval-Based Specification Languages, Chunqing Chen, Jin Song Dong, Jun Sun, Andrew P. Martin
Research Collection School Of Computing and Information Systems
Interval-based specification languages have been used to formally model and rigorously reason about real-time computing systems. This usually involves logical reasoning and mathematical computation with respect to continuous or discrete time. When these systems are complex, analyzing their models by hand becomes error-prone and difficult. In this article, we develop a verification system to facilitate the formal analysis of interval-based specification languages with machine-assisted proof support. The verification system is developed using a generic theorem prover, Prototype Verification System (PVS). Our system elaborately encodes a highly expressive set-based notation, Timed Interval Calculus (TIC), and can rigorously carry out the verification …
Creating An Immersive Game World With Evolutionary Fuzzy Cognitive Maps, Yundong Cai, Ah-Hwee Tan, Zhiqi Shen, Boyang Li
Creating An Immersive Game World With Evolutionary Fuzzy Cognitive Maps, Yundong Cai, Ah-Hwee Tan, Zhiqi Shen, Boyang Li
Research Collection School Of Computing and Information Systems
An increasing number of serious games have been developed to enhance the user experiences in education and training. In order to bridge the gap of game experiences in the virtual environment and in the real life, it is crucial to generate believable characters and contexts in real-time. However, the variables to be simulated for a large-scale serious game are numerous. These variables are involved in complex causal relationships and their values change over time. In view that world modeling has not been well addressed with conventional models, this paper uses a computational model Evolutionary Fuzzy Cognitive Map (EFCM) to model …