Finite State Machine Representation Research Articles

An Interactive and Adaptive Learning Cyber Physical Human System for Manufacturing With a Case Study in Worker Machine Interactions

An adaptive machine learning (ML) based smart manufacturing interactive cyber physical human system (ICPHS) is conceptualized, designed, and implemented. One of its significant properties is an ML model that during deployment self-evolves with the streaming data in a self-labeling manner. This automated adaptive ML system is realized by leveraging the underlying causality during human machine interactions, and initialized by <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a priori</i> domain knowledge and preprocessed public datasets. The system defines a causal and temporal mapping of worker and machine states where one side can label the other automatically. A case study in machines with different automation levels is conducted in a multiuser facility by using finite state machine representations for machine energy states, worker activity states, and interaction transition functions. The fully automated adaptive ML system improves its accuracy for human machine interaction detection by up to 12.5% and shows potential to recognize more fine-grained actions.

Finite state machine for cloud forensic readiness as a service (CFRaaS) events

AbstractThe importance of demonstrating the correctness of forensic analysis tools and automated incident management tools reinforces the need for a finite state machine (FSM) engine that can generate automated forensic processes. Hence, in this paper, we present an event‐based FSM representation for Cloud Forensic Readiness as a Service (CFRaaS), where we also show how the FSM's predetermined states and transitions could be used to formulate an automated forensic process and generate a hypothesis for litigation purposes. Specifically, this proposition comprises a two‐step level CFRaaS‐FSM with possible transitions and states. This representation is useful because it can alert digital forensic investigators on how to deduce current and next state of attacks based on transitions and current states.

Data Driven Modelling of Nuclear Power Plant Performance Data as Finite State Machines

Accurate modelling and simulation of a nuclear power plant are important factors in the strategic planning and maintenance of the plant. Several nonlinearities and multivariable couplings are associated with real-world plants. Therefore, it is quite challenging to model such cyberphysical systems using conventional mathematical equations. A visual analytics approach which addresses these limitations and models both short term as well as long term behaviour of the system is introduced. Principal Component Analysis (PCA) followed by Linear Discriminant Analysis (LDA) is used to extract features from the data, k-means clustering is applied to label the data instances. Finite state machine representation formulated from the clustered data is then used to model the behaviour of cyberphysical systems using system states and state transitions. In this paper, the indicated methodology is deployed over time-series data collected from a nuclear power plant for nine years. It is observed that this approach of combining the machine learning principles with the finite state machine capabilities facilitates feature exploration, visual analysis, pattern discovery, and effective modelling of nuclear power plant data. In addition, finite state machine representation supports identification of normal and abnormal operation of the plant, thereby suggesting that the given approach captures the anomalous behaviour of the plant.

Quantitative and Risk-Based Framework for Unmanned Aircraft Control System Assurance

A generic backtracking process algorithm based on the deductive implementation of a probabilistic Markov/cell-to-cell mapping technique is proposed for risk-informed identification of critical scenarios involving control systems of unmanned aerial systems operating in the National Airspace. A discrete state representation of the unmanned aerial system control system is used that allows tracing fault propagation throughout the system and the quantification of probabilistic system evolution in time. A hybrid state unmanned aerial system control system composed of a discrete state flight executive based on a finite state machine representation of the control system and a continuous state autopilot based on linear control methods is used as a case study. The consequence of interest in the case study is taken to be a deviation from the flight plan at the destination in the waypoint following phase of an unmanned aerial system mission under a “link condition” system configuration. The backtracking process algorithm is implemented to identify the risk-significant scenarios for the case study.

Formalizing REST APIs for web-based communication and SIP interworking

Significant research efforts for the convergence of web and telecommunication services have been recently spent by research and industry stakeholders. The IETF and W3C are cooperating in specifying how web browsers should evolve to natively support communication services. In this perspective, devising novel mechanisms for signaling message exchange and possible interworking between Web- and SIP-based systems is a hot topic of research. Indeed, discussions are still ongoing on how differences between REpresentational state transfer (REST) and session initiation protocol (SIP) models should be coped with. This issue is made more difficult by the lack of rigorous modeling of RESTful systems. In this paper we propose a rigorous approach for design and implementation of REST communication services (e.g., a call service) which leverages formal verification techniques, while allowing to meet a specific performance requirement (i.e., maximum call setup delay). First, we formalize the call resource behavior through a Finite State Machine representation by modeling and simulating service expected behavior and its interworking with SIP User Agents through a tool for the analysis of communicating state machines. Then, we use the model-checking capabilities offered by the tool for the verification of formal properties. Finally, we implement a prototype that, thanks to the previous formalization step, is shown to be functionally correct, while yielding acceptable performance.

Mitigation of Inter-Cell Interference in Flash Memory With Capacity-Approaching Variable-Length Constrained Sequence Codes

We propose using variable-length constrained sequence codes to mitigate inter-cell interference (ICI) in all-bit-line flash memory with multi-page programming for single-level cell, multi-level cell, and triple-level cell flash memory structures. We outline constraints that mitigate ICI in these systems based on an observation of the Gray mapping of data symbols, and we derive the capacity of each constraint. Based on a finite state machine representation of each constraint, we construct variable-length constrained sequence codes with code rates very close to capacity to mitigate ICI in these flash memories. We then exploit the inherent error control capability of the proposed constrained sequence codes to alleviate error propagation. Finally, we integrate these codes with error control codes and present simulation results that demonstrate the enhanced bit error rate performance that can be achieved.

최적화된 동기적 적합성시험 항목의 발견적 생성 방법

This paper presents a new technique for generating an optimum synchronizable test sequence that can be applied in the distributed test architecture where both external synchronization and input/output operation costs are taken into consideration. The method defines a set of phases that constructs a tester-related digraph from a given finite state machine representation of a protocol specification such that a minimum cost tour of the digraph with intrinsically synchronizable transfer sequences can be used to generate an optimum synchronizable test sequence using synchronizable state identification sequences as the state recognition sequence for each state of the given finite state machine. This hybrid approach with a heuristic and optimization technique provides a simple and elegant solution to the synchronization problem that arises during the application of a predetermined test sequence in some protocol test architectures that utilize remote testers.

Estimating Software Reliability by Monitoring Software Execution through OpCode

Previous studies on estimating software reliability employed statistical functions for next system failure prediction. These models used parameters based on assumptions regarding the nature of software faults and debugging process. However, none of the existing models, attempted on ensuring reliable runtime system operation. To serve the current demand of autonomous, reliable, service-oriented software, we present a novel approach for runtime reliability estimation of executable software. The approach can help control software execution at runtime by monitoring software state-to-state transition at runtime. The approach involves representing executable software as an automata using opcode extracted from executable code. The extracted opcode is then used to learn stochastic finite state machine (SFSM) representation of executable software which is later employed to trace software state-to-state transition at each runtime instance. An evaluation of our approach on Java-based Chart generator application is also discussed to explain how we can ensure reliable software execution and prevent software failures at runtime with the proposed approach.

Feature Extraction for Load Identification Using Long-Term Operating Waveforms

This paper introduces a novel finite-state-machine (FSM) representation of long-term load operating waveforms for feature extraction and load identification. An operating waveform is first converted into a quantized sequence of states. Each state is assigned with 2-D numerical values: root mean square (RMS) current values and staying time values. A set of elemental states and events are defined to reduce the number of states and extract numerical features to represent electric loads for classification and identification. Three major categories of repeating patterns in waveforms that correspond to repeating operating actions are summarized and identification methods are proposed for each such category. Test results using a large dataset of real-world waveforms show that the different appliances have distinct ranges of features extracted from the proposed FSM representation, and thus can be identified with high accuracy.

Identifying the effects of modifications as data dependencies

Dependence analysis on an extended finite state machine (EFSM) representation of the requirements of a system under test has been used in model-based regression testing for regression test suite (RTS) reduction (reducing the size of a given test suite by eliminating redundancies), for RTS prioritization (ordering test cases in a given test suite for early fault detection), or for RTS selection (selecting a subset of a test suite covering the identified dependencies). These particular uses of dependence analysis are based on the definitions of various types of control and data dependencies (between transitions in an EFSM) caused by a given set of modifications on the requirements. This paper considers the existing definitions of data dependencies for capturing the effects of the modifications, gives examples of their inaccuracy and incompleteness, proposes new definitions, and proves the soundness and completeness of these new definitions. Any previous work on regression testing using definitions of data dependencies capturing the effects of modifications can benefit from the proposed definitions.

Regression test suite selection using dependence analysis

SUMMARYDependence analysis on an Extended Finite State Machine representation of the requirements of a system under test identifies various types of control and data dependencies between transitions caused by a set of modifications on the requirements. These particular types of dependencies capture the effects of the modifications, that is, their direct effects on the changed parts of the system and their side effects on the unchanged parts of the system. Recent work on model‐based regression testing shows that dependencies capturing direct effects and side effects of the changes made on the requirements can be used for regression test suite (RTS) reduction (reducing the size of a given test suite by eliminating redundancies), for RTS prioritization (ordering test cases in a given test suite for early fault detection), or for RTS generation (designing a test suite covering the identified dependencies). This paper proposes an additional use of such dependencies, namely, RTS selection, which is the process of selecting a subset of a given test suite to form an RTS by considering the coverage of dependencies related to the effects of the modifications. The dependencies marked during this process as uncovered provide a basis for augmenting an (incomplete) RTS with test cases covering uncovered dependencies. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Visual analysis of flow features using information theory.

Over the past decades, scientific visualization has helped tremendously to easily generate meaningful representations of complicated data sets. However, with data correlated over many dimensions and millions of points, only few of the standard techniques are directly applicable. Unsteady multifield visualizations require effective reduction of the data to be displayed. From a huge amount of information, scientists must be able to extract the most informative parts. ?-machines, a concept based on information theory, can handle this task. They're a finitestate machine representation of a system's dynamics, which can be represented as a directed graph (see Figure 1). The nodes encode the local dynamics given as a spatiotemporal stochastic pattern, and the edges indicate the flow's evolution. ?-machines consist of causal states and transitions between them. Several enhancements to the fundamental ?-machine representation can help users identify interesting time intervals, analyze the evolution of unusual local dynamics, and track features over time.

Multiple UIO-based test sequence generation for distributed systems

In developing distributed systems, conformance testing is required to determine whether an implementation under test (IUT) conforms to its specification. With distributed test architectures involving multiple remote testers, testing approaches may become more complicated because of issues known as controllability and observability problems. Based on a finite state machine (FSM) representation of the system’s specification, this paper proposes a new method to generate a test sequence utilizing multiple UIO sequences. The method is essentially guided by the way of minimizing the use of external coordination messages and input/output operations. Experiments are given to evaluate the proposed method.

A DESIGN FOR VERIFICATION APPROACH USING AN EMBEDDING OF PSL IN AsmL

In this paper, we propose to integrate an embedding of Property Specification Language (PSL) in Abstract State Machines Language (AsmL) with a top–down design for verification approach in order to enable the model checking of large systems at the early stages of the design process. We provide a complete embedding of PSL in the ASM language AsmL, which allows us to integrate PSL properties as a part of the design. For verification, we propose a technique based on the AsmL tool that translates the code containing both the design and the properties into a finite state machine (FSM) representation. We use the generated FSM to run model checking on an external tool, here SMV. Our approach takes advantage of the AsmL language capabilities to model designs at the system level as well as from the power of the AsmL tool in generating both C# code and FSMs from AsmL models. We applied our approach on the PCI-X bus standard, which AsmL model was constructed from the informal standard specifications and a subsequent UML model. Experimental results on the PCI-X bus case study showed a superiority of our approach to conventional verification.

Highly Personalized Information Delivery to Mobile Clients

The inherent limitations of mobile devices necessitate information to be delivered to mobile clients to be highly personalized according to their profiles. This information may be coming from a variety of resources like Web servers, company intranets, email servers. A critical issue for such systems is scalability, that is, the performance of the system should be in acceptable limits when the number of users increases dramatically. Another important issue is being able to express highly personalized information in the user profiles, which requires a querying power as that of SQL on relational databases. Finally, the results should be customized according to user needs, preferences and the mark up language of their mobile device. Since the queries will be executed on the documents fetched over the Internet, it is natural to expect the documents to be XML documents. This paper describes an architecture for mobile network operators to deliver highly personalized information from XML resources to mobile clients. To achieve high scalability in this architecture, we index the user profiles rather than the documents because of the excessively large number of profiles expected in the system. In this way all queries that apply to a document at a given time are executed in parallel through a finite state machine (FSM) approach while parsing the document. Furthermore, the queries that have the same FSM representation are grouped and only one finite state machine is created for each group which contributes to the excellent performance of the system as demonstrated in the performance evaluation section. To provide for user friendliness and expressive power, we have developed a graphical user interface that translates the user profiles into XML-QL. XML-QL's querying power and its elaborate CONSTRUCT statement allows the format of the results to be specified. The results to be pushed to the mobile clients are converted to the markup language of the mobile device such as Wireless Markup Language (WML), CHTML or XHTML by the delivery component of the system.

An analytical framework for the Prisoner’s Dilemma: Finite state machine representation for interactions between deterministic strategies

An analytical framework for the Prisoner’s Dilemma is introduced. A finite state machine is used to represent interactions between two deterministic strategies, and two criteria – the ability to exploit others and the ability to form clone clusters – are used to identify the relationships between those strategies. The framework is then used to analyze the properties of memory-l deterministic strategies. The results show a significant understanding of strategy sets. All initial conditions are taken into account, and the result is independent of the value of the payoff matrix. The framework is also capable of analyzing strategies that are encoded in other forms, such as finite automata or rule sets.

Test generation based on control and data dependencies within system specifications in SDL

In Specification and Description Language (SDL), a distributed system is viewed as a collection of communicating processes and its behavior is specified in terms of definitions of these processes. In particular, the desired control and data dependencies that must be established by a potential implementation of the system are expressed in SDL in terms of Extended Finite State Machine representations of communicating processes. To test the control and data flow aspects of the system, such dependencies in a system specification must be identified and utilized for the construction of tests. Based on a model which exposes the control and data dependencies within a specification of a distributed system given in SDL, this paper investigates the generation of tests for the data flow aspects of a system implementation, through the application of data flow oriented test selection criteria which have been originally proposed for testing programs written in procedural languages.

Synchronizable test sequence for multi-party protocol conformance testing

Testing if a multi-party protocol implementation conforms to the specification is achieved by a testing system with k testers (where k≥2), among which synchronization problems are encountered. This paper proposes a new model for test sequence generation, which considers both the costs of input/output operations and external synchronization operations. The multiplex digraph model is transformed from a given finite state machine representation of the protocol (with n states, m transitions and k is considered as constant) using an O( m 2) algorithm, and can represent the testing process cost of an arbitrarily-configured testing system. Application of the model includes: (1) an O( m 2) algorithm for generating the minimum-cost synchronizable transfer sequence, improving an earlier exponential-time backtracking algorithm; (2) an O( m 2) algorithm for generating the synchronizable test sequence based on the T-method, improving an earlier exponential-time backtracking algorithm; (3) an O( n· m 2) algorithm for generating the synchronizable test sequence based on the overlapping U-method, which is an uninvestigated result even for k=2.

Synchronizable test sequences based on multiple UIO sequences

A test sequence generation method is proposed for testing the conformance of a protocol implementation to its specification in a remote testing system where both external synchronization and input/output operation costs are taken into consideration. The method consists of a set of transformation rules that constructs a duplexU digraph from a given finite state machine (FSM) representation of a protocol specification; and an algorithm that finds a rural postman tour in the duplexU digraph to generate a synchronizable test sequence utilizing multiple UIO sequences. If the protocol satisfies a specific property, namely, the transitions to be tested and the UIO sequences to be employed form a weakly-connected subgraph of the duplexU digraph, the proposed algorithm yields a minimum-cost test sequence. X.25 DTE and ISO Class 0 transport protocols are shown to possess this property. Otherwise, the algorithm yields a test sequence whose cost is within a bound from the cost of the minimum-cost test sequence. The bound for the test sequence generated from the Q.931 network-side protocol is shown to be the cost sum of an input/output operation pair and an external synchronization operation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The action-state diagram: a compact finite state machine representation for user interface and small embedded reactive systems

The authors describe the use of action-state diagrams in the software development of small embedded reactive systems. The proposed method allows specification, design, and coding phases to be combined with a formal notation. Direct mapping from design to code is also presented. It is also shown that this method covers all the functionality of the classical state transition diagram. The suitability of this method for user interface problems is also discussed. >