Using a Formal Declarative Language for Specifying Requirements Modelled in CIMOSA

The readability of formal requirements specification languages is hypothesized as a limiting factor in the acceptance of formal methods by the industrial community. An empirical study was conducted to determine how various factors of state-based requirements specification language design affect readability using aerospace applications. Six factors were tested in all, including the representation of the overall state machine structure, the expression of triggering conditions, the use of macros, the use of internal broadcast events, the use of hierarchies, and transition perspective (going-to or coming-from). Subjects included computer scientists as well as aerospace engineers in an effort to determine whether background affects notational preferences. Because so little previous experimentation on this topic exists on which to build hypotheses, the study was designed as a preliminary exploration of what factors are most important with respect to readability. It can serve as a starting point for more thorough and carefully controlled experimentation in specification language readability.

The authors present a framework for developing and verifying knowledge-based systems (KBSs). In this framework, they propose FRORL (frame-and-rule oriented requirements specification language) as a formal requirements specification language which exploits knowledge representation techniques as an aid in the specification, analysis, and development of a knowledge-based system. FRORL uses a combination of resolution refutation, anomaly detection matrix, and algorithm methods to verify a number of properties which might exist in KBSs. Incorporating FRORL and its verification methods in the proposed framework lays a solid foundation for coping with the current issues in KBS verification. >

The paper considers the trends in the development of artificial intelligence technologies in BSUIR for the last five years, lists the main results obtained during this period both in the field of development of artificial intelligence technologies themselves, and in the field of education in artificial intelligence and realization of interaction between teams of specialists working in this field. The necessity of transition to new-generation intelligent computer systems with a high level of interoperability and creation of an appropriate complex technology for their development, maintenance and operation is substantiated. The problems hindering the active development and implementation of new generation intelligent computer systems are considered. The concept of semantic space as a basis for representation and integration of knowledge in intelligent computer systems of new generation is considered. The principles of implementation of hardware platform for interpretation of information processes in the semantic space – associative semantic computer – are considered.

Formal software development begins with formal specification of the user requirements or design of a system. Hence, formal specification languages are used to resolve ambiguities in user requirements or detect design errors at the early software life cycle. Furthermore, specification-based functional testing derives test inputs from its formal specification. However, formal specifications are expressed using set theory or predicate logics which are non-executable. Thus, functional test execution over abstract expressions would be impossible. Therefore, there is a need to refine abstract specification into a form that can be executable. In this paper, an automatic functional testing framework using object constraint language (OCL) formal specification has been proposed. The major objective of this paper is to describe how the refinement processes are integrated into the specification-based testing framework.

Traditional structured analysis and design methods have been criticized because the methods lack formality to provide a design for rigorous development. Several approaches have been developed for verifying a design by integrating traditional structured analysis and design methods with formal specification languages. However, the integration of traditional structured analysis and design methods with formal specification languages may confuse the problem definition and understanding with the attempt to define system structures and algorithms in the design phase. In addition, formal specification languages may add complexity to the design due to the complexity of the language syntax and semantics. In this paper, we are presenting an approach to verification of a structured design in HOS without using formal specification languages. Rules for the partial and total correctness of the design are also discussed.

The complexity of designing concurrent and highly-evolving interactive systems has grown to a point where system verification has become a hurdle. Fortunately, formal verification methods have arrived at the right time. They detect errors, inconsistencies and incompleteness at early development stages of a system formally modeled using a formal specification language. -calculus (Milner, 1999) is one such formal language which provides strong mathematical base that can be used for verifying system specifications. But manually verifying the specifications of concurrent systems is a very tedious and error-prone work, especially if the specifications are large. Consequently, an automated verification tool would be essential for efficient system design and development. In addition, formal verification tools are vital ingredient to fully harness the potential of component-based software composition. The authors developed such an automated verification tool which is highly portable and seamlessly integrates with the visualization, reduction and performance evaluation tools introduced (Ahmad & Rahimi, 2008; Rahimi, 2006; Rahimi et al., 2001, 2008) to provide a comprehensive tool for designing and analyzing multi process/agent systems. Open-Bisimulation (Sangiorgi, 1996) concept is utilized as the theoretical base for the design and implementation of the tool which incorporates an expert system implemented in Java Expert System Shell (JESS) (Friedman-Hill, 2003).

In Wide Area Networks (WANs)inconsistencies among the security policies of Administrative Domains (ADs) may cause severe security flaws. Recently, security policies are written in natural language and as they get more complicated, even for an expert it might be impossible to detect such inconsistencies. However, when a formal language is used, it might be possible to make verification of security policies by automated theorem proving tools. Due to the existence of mobile devices such as laptops, PDAs and mobile agents, we need a formal language that is capable of defining the concept of mobility. In this paper, we extend Mob adtl [1] according its refinement methodology to obtain a formal policy specification language for an 802.11 WLAN with enhanced security network.

Three main approaches to building computer systems are analyzed and allocated: software, hardware, and problem-oriented. A problem-oriented approach was chosen for the implementation of CNN. This approach uses a processor core with hardware accelerators that implement basic CNN operations. The development of computer systems for the implementation of CNN should be carried out based on an integrated approach. This approach includes a modern element base, existing hardware, and software for the implementation of the CNN; methods and algorithms for the implementation of CNN; methods, algorithms, and VLSI structure for the implementation of basic operations of the CNN; methods and means of computer-aided design of hardware and software focused on the implementation of CNN computer systems. For the development of computer systems for the implementation of CNN chosen approach, which includes: variable composition of equipment; use of the basis of elementary arithmetic operations; organization of the process of calculating the scalar product as execution single operation; pipeline and spatial parallelism; localization and simplification of links between the steps of the conveyor; coordination of the time of formation of input data and weighting coefficients with the duration of the conveyor cycle. It is shown that in order to reduce the processing time of large images, it is most expedient to use parallel-stream VLSI -implementation of basic operations. The modified Booth algorithm for forming partial products in a parallel-threaded computing device is selected, which decreased the number of steps in the pipeline. The method of group summation has been improved, which, with multi-input single-digit adders, combined according to the principle of the Wallace tree, provides a reduction in summation time. The method of parallel-flow calculation of scalar product in a sliding window is developed, which, by coordinating the time of receipt of columns of input data and weighting coefficients with the duration of the conveyor cycle, provides high efficiency of equipment use and calculations in real-time. The main ways regarding coordination of the time of receipt of input data columns and weighting coefficients with the duration of the conveyor stroke of hardware that implement two-dimensional convolution are determined. The hardware structure for the realization of two-dimensional convolution in a sliding window, which is focused on VLSI- implementation with high efficiency of equipment use, has been developed. Programmable logic integrated circuits selected for the implementation of hardware accelerators. Single-bit 7, 15, and 31 input adders were developed and modeled on the basis of FPGA EP3C16F484 of the Cyclone III family of Altera company, and an 8-input 7-bit adder was synthesized on their basis.

The Live Sequence Charts (LSC) language is a formally rigorous variant of the well-known scenario language Message Sequence Charts (MSC). LSCs yield expressive power by means to distinguish mandatory and scenario behaviour, means to characterise by another scenario the context in which a specification applies, and means to distinguish required from possible progress, i.e. to require liveness. From the original proposal by Damm & Harel [1], two slightly different dialects emerged, one in the context of LSC play-in and -out [2] and one for the use of LSCs as formal requirements specification language in formal, model-based approaches to software development [3]. In this paper, we investigate the expressive power of LSCs in the sense of [3]. That is, we first (constructively) show that for each LSC there is an equivalent CTL * formula. Complementing existing work, we show that the containment is strict, that is, not each CTL* formula has an equivalent LSC. To complete the discussion, we present for the first time a way back, from a syntactically characterised fragment of CTL* to the subset of bonded LSC specifications, thereby establishing an equivalence.

Standardization of Formal Specification Languages

The Unified Modeling Language (UML) has become a widely adopted standard in the software development industry. Unfortunately, the UML is a semi-formal language which lacks precisely defined constructs. Z language is a formal specification language. Formal languages are used to ensure that systems meet regulations and standards. This paper aims to reduce risks associated with software development and increase safety and reliability. This goal is achieved by formalizing the syntax of (a sub-set of the popular UML diagrams (Use Case diagram, Class diagram, and State Machine diagram) using Z specifications.

Often the most effective diagrams are those which are very simple. However there is a strong tendency, particularly prevalent in visual formal modelling and specification languages, to take a diagrammatic language which at core is very simple, and then add many extensions and features to make it more expressive - often making it so expressive that the diagrams produced in the language are no longer readable; or at least, the diagrams are no longer obviously a more effective form of representation than a text-based one. Both the design of effective visual formal modelling and specification languages, and the effective formalisation of (the semantics of) such visual languages requires the unification of results from visual language theory, cognitive science, empirical psychology and graphic design. Integrating results from such diverse fields is a non-trivial task, which may be approached through a decomposition of the study of issues of effectiveness in diagrammatic languages according to analogous understandings of (written and spoken) natural languages.

The "Hacker Curriculum" exists as a mostly undocumented set of principles and methods for learning about information security. Hacking, in our view, is defined by the ability to question the trust assumptions in the design and implementation of computer systems rather than any negative use of such skills.

In screening and evaluating the background of applicants for careers in data processing, a considerable emphasis is placed on the ability of the applicant to work as a member of a team. This is because many required skills in data processing, specifically in the commercial environment, can only be obtained through individual work as a member of a team. This paper focuses on a method for simulating the business data processing environment through class project teams. The simulation is demonstrated through a discussion of the process of selecting the teams and projects, the frequent problems faced by team members, the background knowledge required, and the methods used in evaluating the projects.The benefits that can be derived by taking the programming team approach to the design and implementation of computer systems have been widely discussed in the literature [1, 2, 3]. This approach is receiving increasing attention in the commercial environment [4]. In addition, several new system design techniques [5, 6, 7, 8, 9] are becoming increasingly popular and the ideas of structured programming [10, 11, 12] are widely known. We feel, therefore, that an important part of the preparation for a career in information processing should include participation as a member of a programming and design team.In this paper we demonstrate the methods that we have used to create a project team environment in the classroom. These methods are based on our commercial experience and experience gained from conducting such classes for a combined total of seven semesters. Overall, the projects resulting from these team efforts have been of high quality and the students' reactions have been very favorable. The students from these courses that sought careers in data processing were able to find jobs rapidly. They have been highly successful in their careers.In interviews with our graduates they indicated that the experiences they gained from the project team classes were main factors in obtaining employment and the success they achieved in their work.

Latch and flip-flop design in QCA technology with minimum number of cells