Formal Analysis Techniques Research Articles

Towards a hybrid formal analysis technique for safety-critical software architectures

Given the catastrophic damage that bugs in critical systems can inflict on human life and its socio-economic environment, the use of rigorous analysis techniques while developing such systems is ge...

Hopf Bifurcation of a Gene-Protein Network Module with Reaction Diffusion and Delay Effects

The infinite dimensional partial delay differential equation is set forth and delay difference state feedback control is considered to describe the cell cycle growth in eukaryotic cell cycles. Hopf bifurcation occurs as varying free parameters and time delay continuously and the multi-layer oscillation phenomena of the homogeneous steady state of a simple gene-protein network module is investigated. Normal form is derived based on normal formal analysis technique combined with center manifold theory, which is further to compute the bifurcating direction and the stability of bifurcation periodical solutions underlying Hopf bifurcation. Finally, the numerical simulation oscillation phenomena is in coincidence with the theoretical analysis results.

Towards a hybrid formal analysis technique for safety-critical software architectures

Towards a hybrid formal analysis technique for safety-critical software architectures

Modelling transport emissions in an uncertain future: What actions make a difference?

A range of technology and policy actions can be put in place to reduce carbon emissions from passenger cars, this paper aims to prioritise between them, based on their likely impact and uncertainty. Formal sensitivity analysis techniques are used for the first time to determine the relative importance of factors affecting future emissions from passenger vehicles in Great Britain.The two most important actions to limit future life-cycle CO2 emissions involve shifting to electric vehicles and limiting trends towards larger and more powerful vehicles. According to our analysis over 80% of the uncertainty in future cumulative CO2 emissions can be attributed to uncertainty in electric vehicle uptake and vehicle size and power. These variables are a priority for transport policy makers. The analysis also highlights variables of comparatively low importance; these include the share of hybrid electric vehicles, the Rebound Effect and the utilisation factor of PHEVs.

Analysis and Application of Formal Concept in Information Science

Based on Information Science, new mechanism, two types and basic characteristics of information processing are discussed in the paper. Besides, as a new method of unsteady information processing, the paper not only introduces some basic ideas, concepts, techniques of formal concept analysis (FCA) and Galois liaison but also expounds the feasibility of formal concept analysis for knowledge representation and knowledge acquisition through examples. Finally, the application and research progress of formal concept analysis in information science are further analyzed in the paper.

Statistical Engineering for Wind Tunnel Testing of Mars Parachute Designs

Formal experiment design and analysis techniques featuring design of experiments were applied to a Mars parachute wind tunnel test. The experiments were part of an extensive study conducted in 2014 by the NASA Engineering and Safety Center to evaluate the performance of two candidate parachute systems. Reduced scale models of the legacy Disk-Gap-Band (DGB) parachute and new Supersonic Ringsail (SSRS) were compared for both model fidelity and performance measures. Two tests, conducted in the NASA Langley Transonic Dynamics Tunnel, are described with emphasis on statistical engineering principles. The first test compared drag coefficients between models of the same canopy at Earth atmospheric pressure but at mission dynamic pressures. The experiment proved that any manufacturing differences between models were not detectable in drag coefficient measurements. The second test focused on parachute drag coefficient modeling for both canopy designs and two fabric permeabilities over a representative range of mission dynamic pressures and Mach numbers. The SSRS was found to have higher drag coefficients in comparison to the DGB for both canopy material permeabilities over the operational range of Mach numbers and dynamic pressures.

Cyber security for fog-based smart grid SCADA systems: Solutions and challenges

This paper presents a comprehensive survey of existing cyber security solutions for fog-based smart grid SCADA systems. We start by providing an overview of the architecture and the concept of fog-based smart grid SCADA systems and its main components. According to security requirements and vulnerabilities, we provide a classification of these solutions into four categories, including authentication solutions, privacy-preserving solutions, key management systems, and intrusion detection systems. For each category, we describe the essence of the methods and provide a classification with respect to security requirements. Therefore, according to the machine learning methods used by the intrusion detection system (IDS), we classify the IDS solutions into nine categories, including deep learning-based IDS, artificial neural networks-based IDS, support vector machine-based IDS, decision tree-based IDS, rule-based IDS, Bloom filter-based IDS, random forest-based IDS, random subspace learning-based IDS, and deterministic finite automaton-based IDS. The informal and formal security analysis techniques used by the cyber security solutions are tabulated and summarized. In addition, we provide a taxonomy of attacks tackled by privacy-preserving and authentication solutions in the form of tables. Based on the present study, several proposals for challenges and research issues such as detecting false data injection attacks are discussed at the end of the paper.

Markov Regenerative Models of WebServers for Their User-Perceived Availability and Bottlenecks

The Internet world is moving toward a scenario where users and applications have very diverse service expectation, making the current best-effort model inadequate and limiting. To be able to design high-availability service systems, it is essential to consider not only the actual failure and recovery behavior of the service infrastructure, but also the behavioral aspects of its user and their subjective perceptions and reactions in the wake of failure events. In this paper, we propose to use Markov regenerative process (MRGP) models to study the availability of Internet-based services perceived by a Web user on two different online service scenarios: (1) single-user-single-host and (2) single-user-multiple-host. The MRGP models capture the interactions between the service facility and the user. We also detect its parameter bottlenecks by applying the formal sensitivity analysis technique. The trends of the users’ perceived unavailability are analyzed with the changed different parameter values, and the necessity of the sophisticated MRGP modeling is evidenced by the comparisons with the corresponding continuous time Markov chain (CTMC) models, which show that the popular convenient CTMC models tend to overestimate user-perceived service unavailability. Finally, controlled experiments are carried out on a real Web service to demonstrate the proposed approach.

The Mad March for US Capital Markets: Impact of COVID-19 Pandemic on Dow Jones Industrial Average

Financial Markets, considered as backbone of a capitalist economy, when under pressure exogenously, is a cause of concern for both domestic and foreign investors, triggering various false alarms. When investors lose confidence in its structure, panic buying and selling kicks in, amplifying uncertainty into real economy. The stock markets of US, which has undergone one of the finest sophistications in history, witnessed the most horrific volatility due to COVID-19 pandemic, signifying a chaos created by the microscopic virus in financial world. Towards establishing the magnitude of panic sell off effect in stock markets, this paper uses formal event study analysis technique. In this study we examine the aftermath of first locally transmitted COVID-19 case in US, on Dow 30 and its constituent units, representing a unique industry. The empirical results indicate significantly negative cumulative abnormal returns, measuring magnitude of “blood-bath” on The Wall Street.

시황 및 ICO 자금조달 결과에 따른 블록체인 스타트업 조직 구성에 관한 연구

ICO is a newly attempted funding method in the blockchain field in 2013, with an increasing number of projects each year. However, the number of startups failing to raise funds below $100,000 has risen from 51% in 2017 to a maximum of 75% in the second quarter of 2018. Accordingly, startups preparing for ICOs need to study what factors affect successful funding.BR In this study, we apply the formal concept analysis technique to classify the major occupational groups in the block chain field as development, legal, public relations, business development, financial and investment attraction. As a result of the analysis, we found that the job of the marketing is particularly important when the market situation is good. When the market situation is not good, the job of the business development such as securing a strong business partner was identified as important.

The influences the tangible and intangible cultural heritage in formulating the Architectural language Case study: The Heritage city of GeorgeTown, Penang- Malaysia

The identity of the heritage space perceived by the visitor depending on the tangible and intangible elements, which is influenced by the cultural values. The sense of place is the generator of the cultural heritage space. The physical elements of the space in the street have the role in the activating the identity. GeorgeTown is the heritage city of the northern state of Penang Island in Malaysia, which listed in the World Heritage Site (WHS) by the UNESCO in July 2008. GeorgeTown well known as a colorful culture place, which attracts millions of tourists yearly. The contemporary needs of the city as a host of foreign and local visitors create type of shifting on the identity of the place. The architectural elements of the facades started to lose the authenticity of the heritage value during the rehabilitation, reconstruction, and new construction processes. The problem of the current study observed from site as urgent needs to establish a standard of creating physical cultural heritage space du the waves of changing in the original characteristics of the physical elements in the street. The study obtained a research question, which are, “what is the architectural language of the cultural heritage space, which can enhance the cultural heritage image of the GeorgeTown”. Therefore, the study aim is to find the components and the rules of this language. However, Beach Street selected as a case study, which is one of the most important heritage trails in Georgetown. The study used qualitative approach, using visual observation and in-depth interview with experts and pedestrians. In the current study used formal, content, and phenomena analysis techniques. The results show, that the architectural language included two systems, formulating and influences systems. The results of the study presented as a model of the architectural language, which contained the architectural elements, principles, and relationship. While, the influence system included the architectural style, symbols, and elements. The architectural language in the heritage cities has a rule in the conserving the cultural heritage space.

Preventing Harm From Fluoroscopically Guided Interventional Procedures With a Risk-Based Analysis Approach

PurposeFluoroscopically guided interventional (FGI) procedures often have lower complication rates compared with alternative surgical procedures, providing an option for patients with a high risk of perioperative mortality. Although severe radiation injuries are rare, patients receiving peak skin doses exceeding 3 Gy can suffer from radiation-induced tissue injuries, ranging from transient erythema to nonhealing wounds. As these iatrogenic injuries may manifest weeks to months postprocedure, proper diagnosis and timely medical intervention are less likely. Clinically, the lack of situational awareness for monitoring air kerma continues to be a challenge despite the recommendations of numerous organizations on ways to achieve fluoroscopy safety. For patient safety efforts, this study aimed to identify and mitigate systematic gaps associated with potentially high-radiation dose fluoroscopic procedures in US Department of Veterans Affairs (VA) and non-VA medical institutions. MethodsIn this study, a multi-institutional team utilized Healthcare Failure Mode and Effect Analysis (HFMEA) on an example implantable cardioverter defibrillator lead extraction procedure. ResultsWith this approach, 29 interventions were devised and prioritized by feasibility, cost-effectiveness, and expected clinical impact. Five of the 29 interventions were recommended for immediate implementation or piloting. ConclusionsThis work demonstrates the application of formal risk-based analysis techniques in FGI procedures. These high priority interventions may be valuable for other facilities to consider when performing potentially high–radiation dose procedures and conducting risk-benefit analyses. Formal risk analysis techniques such as the HFMEA process are recommended for other facilities to use to improve safety for their high-risk procedures.

An Integrated Modeling, Simulation and Analysis Framework for Engineering Complex Systems

The discipline of component-based modeling and simulation offers promising gains in reducing cost, time, and the complexity of model development through the (re)use of modular components. Model-driven development suggests 1) the realization of a complex system using a conceptual model; 2) its automatic transformation into an executable form using transformation rules, and; 3) its automatic verification using a formal analysis technique for an accurate assessment of its correctness. Both approaches have numerous complementary benefits in rapid prototyping of complex systems using model reuse. In this paper, we propose a framework grounded in a combination of component-based and model-driven approaches to promote rapid prototyping of complex systems through the effective reuse of the simulation models. Our proposed process allows developers to 1) build or select existing components and compose them to formulate the conceptual models of complex systems; 2) automatically transform the conceptual models for the rapid implementation and simulation, and; 3) automatically verify them as per the requirement specifications. We propose the use of the extended finite-state machine (EFSM) as conceptual modeling formalism, anylogic simulation platform for the implementation, and probabilistic model checking technique using communicating sequential process (CSP) formalism for the verification. Finally, we present a case study of a real-time adaptive cruise control system to demonstrate the functionality of our framework. Our proposed component-based model-driven approach facilitates rapid prototyping and effective meaningful reuse of complex system models, which further accelerates the modeling, simulation, and analysis process of real-time systems and aids in complex engineering designs and implementations.

Exploring first-year undergraduates’ perceptions of poetry and their acquisition of skills in reading poetry for study at university

There is significant evidence drawn from student evaluations that students embarking on undergraduate English degrees feel uneasy about studying poetry and that this anxiety has an effect on the course choices they make as they progress through the three years of their programme. This study aims to investigate the causes of students’ responses to poetry and to make a beginning in looking at the implications that this has for teaching and learning. It explores students’ acquisition of skills and attitudes that make poetry-reading a rewarding activity. Data has been gathered from focus groups with first-year undergraduate students in an English department at a UK university to discover what perceptions of poetry are held by students and what factors in teaching contribute to the development and/or perpetuation of these perceptions. In brief, the study finds that for effective teaching the cultivation of enthusiasm for poetry is just as important as building technical vocabulary and learning techniques of formal analysis. There is some evidence that the latter flows out of the former. It also finds that students feel the former is often overlooked in the classroom.

Checking business process evolution

Business processes support the design and implementation of software as workflows of local and inter-organisation activities. Tools provide the business process designer with modelling and execution facilities, but they barely provide formal analysis techniques. When one makes a process evolve, for example by refactoring it or by adding new features in it, it is important to be able to check whether, and how, this process has changed, and possibly correct evolution flaws. To reach this objective, we first present a model transformation from the BPMN standard notation to the LNT process algebra and LTS formal models. We then propose a set of relations for comparing business processes at the formal model level. With reference to related work, we propose a richer set of comparison primitives supporting renaming, refinement, property and context-awareness. We also support BPMN processes containing unbalanced structures among gateways. In order to make the checking of evolution convenient for business process designers, we have implemented tool support for our approach as a web application.

Automatic Configurable Hardware Code Generation for Software-Defined Radios

The development of software-defined radio (SDR) systems using field-programmable gate arrays (FPGAs) compels designers to reuse pre-existing Intellectual Property (IP) cores in order to meet time-to-market and design efficiency requirements. However, the low-level development difficulties associated with FPGAs hinder productivity, even when the designer is experienced with hardware design. These low-level difficulties include non-standard interfacing methods, component communication and synchronization challenges, complicated timing constraints and processing blocks that need to be customized through time-consuming design tweaks. In this paper, we present a methodology for automated and behavioral integration of dedicated IP cores for rapid prototyping of SDR applications. To maintain high performance of the SDR designs, our methodology integrates IP cores using characteristics of the dataflow model of computation (MoC), namely the static dataflow with access patterns (SDF-AP). We show how the dataflow is mapped onto the low-level model of hardware by efficiently applying low-level based optimizations and using a formal analysis technique that guarantees the correctness of the generated solutions. Furthermore, we demonstrate the capability of our automated hardware design approach by developing eight SDR applications in VHDL. The results show that well-optimized designs are generated and that this can improve productivity while also conserving the hardware resources used.

Reasoning about sensing uncertainty and its reduction in decision-making for self-adaptation

Abstract Adaptive systems are expected to adapt to unanticipated run-time events using imperfect information about themselves, their environment, and goals. This entails handling the effects of uncertainties in decision-making, which are not always considered as a first-class concern. This paper contributes a formal analysis technique that explicitly considers uncertainty in sensing when reasoning about the best way to adapt, together with uncertainty reduction mechanisms to improve system utility. We illustrate our approach on a Denial of Service (DoS) attack scenario and present results that demonstrate the benefits of uncertainty-aware decision-making in comparison to using an uncertainty-ignorant approach, both in the presence and absence of uncertainty reduction mechanisms.

Towards a mutation analysis of IoT protocols

ContextMutation testing and analysis is concerned with the introduction of single faults (or errors) into a system’s design, specification, implementation or interface and then testing or analysing the effects caused by those faults or errors on the system’s properties and behaviour. Such faulty entities are called mutants. ObjectiveThis short paper sketches the idea that mutations can be used to identify whether protocol implementations may deviate from the standards defining those protocols. MethodsWe apply formal analysis techniques to analyse the harmful effects of mutations on IoT protocol specifications, most importantly, e.g. whether those mutations will violate the IoT protocol standard. ResultsWe discovered in our initial investigation one interesting case where a mutant protocol specification may lead to implementations that drop every message intended for publication to applications without breaking the standard of quality of message delivery in the protocol standard. ConclusionWe believe as a result, that there is some additional investigation needed in this direction that could be beneficial in implementing future more reliable protocols and also that the current standards need to be revised to take care of such scenarios.

Organisation-Oriented Coarse Graining and Refinement of Stochastic Reaction Networks.

Chemical organisation theory is a framework developed to simplify the analysis of long-term behaviour of chemical systems. In this work, we build on these ideas to develop novel techniques for formal quantitative analysis of chemical reaction networks, using discrete stochastic models represented as continuous-time Markov chains. We propose methods to identify organisations, and to study quantitative properties regarding movements between these organisations. We then construct and formalise a coarse-grained Markov chain model of hierarchic organisations for a given reaction network, which can be used to approximate the behaviour of the original reaction network. As an application of the coarse-grained model, we predict the behaviour of the reaction network systems over time via the master equation. Experiments show that our predictions can mimic the main pattern of the concrete behaviour in the long run, but the precision varies for different models and reaction rule rates. Finally, we propose an algorithm to selectively refine the coarse-grained models and show experiments demonstrating that the precision of the prediction has been improved.

Review: Grasshopper Algorithmic Modeling for Rhinoceros 5

Grasshopper Algorithmic Modeling for Rhinoceros 5 http://www.grasshopper3d.com It is only since the nineteenth century that we have been able to speak of Western architectural history and design as clearly separate disciplines. To make this distinction, we have had to draw clear borders between the disciplines’ respective methods and practices. This has not always been easy. Historians have long used the tools of design—such as plans, elevations, and diagrams—as part of their analytical tool kit, while architects have used the tropes and techniques of historical formal analysis through diagrams as a projective act of design in its own right. Sometimes the distinction collapses completely. When Rudolf Wittkower published his famous eleven diagrams of known Palladian villas, he included an additional one titled “Geometric Pattern of Palladio's Villas.”1 While each of the eleven original diagrams was congruent with the building plan on which it was based—as if it had been traced—the additional diagram depicted a set of idealized geometric relationships that did not correspond to the footprint of any one villa. This twelfth diagram, freed as it was from reference to a specific historical object, uncomfortably blurred the distinction between historical analysis and design proposition. To complicate this distinction further, architects have sometimes used formal diagrammatic analysis as a generative design method. Peter Eisenman, for example, has used a derivative of Wittkower's twelfth diagram as the starting point for rule-based formal development of a series of houses.2 More recently, architects grappling with a range of new digital tools and techniques have returned to history as a means of grounding their work within the core of the discipline through the digitally mediated formal analysis of precedents. Their tools—primarily the application of computer-aided design and scripting—along with the methods by which they are applied ask us to rethink the role of history in architectural production and offer new techniques …