A Three-Aspects Approach for Technical Systems Quality Evaluation

Abstract

A conceptual approach to technical, including cyberphysical, systems quality evaluation at the stage of exploitation in three aspects: functional, technical and process is presented in the article. The dominance of the reductionist approach to the evaluation of technical systems, which is impractical in terms of management decisions at the current level of complexity of systems, is shown. A general approach, which allows considering and researching functional, technical and process approaches to evaluation, as a holistic evaluation system based on their interaction, within a single information structure based on project specifications and system information links, is offered. The presentation of the informational structure in the form of the sensory infrastructure is considered, the model and the scale of the quality state evaluation, based on relative value of the amount of information, are given. A model, that combines technical, functional and process aspects into the quality state evaluation unified system, is developed.

Introduction. The main idea of the fourth industrial revolution (Industry 4.0), which was started at the 2011 Hannover Fair, is the automation of all spheres of life through the widespread introduction of intelligent technologies. By definition, the driving force behind Industry 4.0 is cyber-physical systems - technical systems (TS), operating in an automatic mode under the control of artificial intelligence, which, depending on the user’s production needs, is able to provide an autonomous change in the behavioral logic and work patterns of the system’s components. In practice this means that information about the necessary technological processes is embedded in the product (service) as we move through the stages of creation, which allows us to implement fully flexible “individual production or service to order”, moreover, the decision to change the functional behavior of the components and the system in generally accepted by artificial intelligence and not controlled or partially controlled by specialists. Of particular concern is autonomous operation and appropriate decision making in the event of abnormal situations, for example, in case of failures in technological processes or failures of equipment or software. What decision on system management will be made by artificial intelligence and which, as a result of the decision, will be his behavior, is perhaps the most difficult and uncertain question.

In this context, the definition of the qualitative state and, accordingly, the quality of work and TS behavior and their components at the Operation stage acquires great weight what determines not only the release of products or the provision of services, but also the safety of human life and environmental safety.

Problem statement. An analytical review of literary sources showed the presence of two main approaches to the analysis and determination of the qualitative state of artificial, including technical, systems - functional and process. The main thesis of the publications is a direct comparison of these approaches, which consists in a dualistic view of their interaction from direct opposition to determining them parallel to the current ones with similarities in basic premises. For example, turn to take ISO/IEC 25010: 2011 standard [1], where the definition of the qualitative state of the system begins with measuring and assessing the quality of processes, as the basis for further definition of the quality of the system under study. Moreover, the separation of problem-oriented functional properties (system or software functional specifications) and quality properties is clearly stands out, the latter, by standard definition, have nothing to do with the former. But the standard introduces a quality characteristic - functional suitability, criticizing which, it is indicated in [2] that a software application can be suitable for a certain production process, be useful, but not perform, or partially not perform some of its functions.

Another approach to assessing systems is to assess their technical condition (monitoring), which is determined by the value of the monitored parameters during technical diagnostics. According to DSTU 2389-94 [3], determining the state of the system under study is carried out at a certain point in time, under certain environmental conditions, by the values of the parameters established by the technical documentation. Conformity or non-conformity assessment takes place according to the criteria of malfunction, defect, degree of deterioration, regulation deviation, and the like.

The above allows us to conclude that there is reductionism in assessing the state of technical systems, which is expressed in a differentiated approach to assessing and the absence of research publications that combine all three approaches when assessing the TS state.

A separate assessment of the state of technical systems arose according to their evolutionary development, from simple to System systems and, accordingly, from determining the quality of the functional state, the technical state to the process state. The process approach began to be applied when systems reached such complexity that testing all their functions and technical condition in all modes became almost impossible. Its essence is quite simple: if the life cycle processes of the studied (target) system correspond to the best world practices, then, most likely, its work will be of high quality [4]. The key phrase here is “probably”, which means that the quality of the work may NOT meet the necessary requirements. It is possible to check this only at the Utilization Stage, assessing the general condition of the TS, taking into account the functional, technical and process aspects.

The aim of the presented study is to determine an approach that combines technical, functional and process aspects into a single system for assessing the quality state of a technical system at the Utilization Stage.

The object of the research work is methods and models of a unified system for assessing the qualitative state of a technical system at the Utilization Stage.

The subject of the research is the assessment of the qualitative state of the technical system at the Utilization Stage.

The scientific novelty of the work consists in the definition and development of an approach and model of a unified system for assessing the qualitative state of technical systems, taking into account the functional, technical and process aspects of its work.