Jānis Osis

The Topological Functioning Model as a Reference Model for Software Functional and Non-functional Requirements

Specification of non-functional requirements in models is a challenge due to extra-functional nature of the requirements. The topological functioning model (TFM) can serve as a reference model for specifying mappings from both functional and non-functional requirements to the functional characteristics and structure of the modelled system. The main principle presented in this paper extends a way of specification of the TFM functional characteristics and causal relationships and provides a specification of mapping types as tuples of TFM functional features extended with requirements and characteristics of these relationships, namely, completeness and overlapping for functional requirements, and scope and dynamic characteristics for nonfunctional ones. This allows propagating the mappings from requirements to software implementing constructs, that would be useful for further architectural decisions and development of test cases.

Verification of Causality in the Frame System based on the Topological Functioning Modelling

Causality is universal relations among phenomena (states, facts, elements, functions) in the system. Verification of causality in the knowledge frame system based on principles of the topological functioning modelling can help in discovering inconsistencies such as incompleteness, ambiguity or contradictions in knowledge on system’s functioning. The method for such verification is presented in this paper. It is based on topological and functioning properties of the topological functioning model including the definition of continuous mapping between topological spaces. The method helps in discovering inconsistent combinations of cause-and-effect relations or a lack of them. Functional characteristics of the system involved in these relations are marked as doubtful. The results of verification require additional investigation by a software developer. A use of the proposed method can lead to more thorough system analysis before development of the solution.

Joint Usage of Frames and the Topological Functioning Model for Domain Knowledge Presentation and Analysis

Joint usage of frames and Topological Functioning Model (TFM) provides proper analysis of knowledge in the domain under study. The main issue in domain knowledge analysis is completeness of discovered knowledge. Formal representation of the knowledge in frames allows automated construction and validation of the TFM, thus allowing to discover white places in knowledge. Analysing TFM metamodels, the structure of the frame system for generation of the TFM is proposed. The frame system leads to highlighting structural knowledge, while validation of the generated TFM shows white places in behavioural knowledge. Validation of the TFM does not guarantee the complete identity of obtained knowledge to the domain, since the knowledge is based on expert opinions. Thus, analysis of the problem domain is shifted from the separate investigation of dynamic and structural aspects of the system to holistic understanding of domain phenomena. The presented results should be refined if other derived models are added.