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The article exposes description of features of the combined approach application to the evaluation of measurement results uncertainty. The aim of this work is the justification and development of new science-driven approaches to achieve maximum efficacy of measurements on the criteria "accuracy/costs" at the stated level of confidence. It provides theoretical base for correctness of combined approach to assess measurement results uncertainty. There is proposition to conventionally divide measurement process into fragments-combining objects, each from shall be considered as individual element for evaluation. It is well known that combining objects can be formed by grouping individual components (resources) of the measurement process either via separate stages of the measurement process. Correctness of such approach is based on the application of "resource" and "process" approaches as regards identification of the factors that affect the measurement results uncertainty. This article provides recommendations on selection of model or empiric approach for evaluating of particular contributions from combining objects of different types into total uncertainty of the final measurement result. In order to improve the validity of empiric approach of the criteria of sufficiency of measurement method uncertainty examination was formulated. It is recommended to evaluate the total uncertainty of the final measurement result by complexation of evaluations of particular total uncertainty of the results for all fragments according to the uncertainties distribution law. It is determined two typical cases of effective application of the combined approach to evaluation of measurement results uncertainty: method of direct measurements and method of indirect measurements. This article considers features of effective application of the combined approach for both situations providing corresponding examples. Special attention is paid to the application of the combined approach to assessing the test results uncertainty. As distinct from the measurement process realized under normal conditions, testing process includes additional external influence factors that are determined by test conditions.

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The necessity for scientific and methodical study of methods for monitoring the characteristics of flameresistance of building structures has the highest priority in the field of fire safety. The aim of this work was to provide the required degree of reliability of the results of quality control of flame-resistant coatings of building structures and high efficiency of decisions due to the risk-based approach to the development of control methods.Substantiated risk-based approach to the development of methods of control, involving the consideration on the basis of process model, control flame-resistance of building object in all possible potential problems that can cause the risk of incorrect decision-making. A model of the risks arising from the control of the flameretardant coating thickness has been developed. Two major risk groups have been identified. The first group is related to the uncertainty of coating thickness measurement at a single control point. The second group of risks is related to the unrepresentativeness of selective control over the entire surface of the construction object as a whole Potential risk sources have been identified for each group. For the entire range of sources of particular risks the results of studies of the mechanisms of their manifestation, the estimated degree of influence on the accuracy of the control of compliance of flame-retardant coating thickness requirements. The analysis is carried out on the basis of both theoretical and experimental statistical studies on a number of construction projects.According to the results of the analysis of all particular risks of control unreliability, rational ways of their minimization in the form of technical or organizational and technical measures, which are refl in the developed project of the control method, are proposed. Project control method was built on the basis of a agreed scheme of control of the thickness of the fl coating of building structures sequentially the three parties. Formulated and solved the task of the metrological control of the thickness of the flame-retardant coating as indirect measurement methods non-destructive thickness measurements. Theoretical and applied aspects of the process of flame-retardant coating thickness control of building structures under conditions of high risk of making incorrect decisions on the results of control are considered.

The paper identifies the problem of ensuring the reliability of measurement results of quality characteristics as subjective values and their correct application in logical and mathematical models of making decisions. The purpose of this study is to increase the reliability of expert evaluation of individual characteristics of the quality of processes, products, systems.The article describes basic methodological approaches to subjective measurements represented by the classical, operational and representational theories of measurement. The most acceptable for the purposes of ensuring the reliability of the expert evaluation of the single quality characteristics a representative theory, suggesting that the subjective value can be measured only in nominal or ordinal scales was determined. The contradiction is established: the possibility of measuring of single quality characteristics in the ordinal scale does not meet the needs of specialists in the field of quality, whouse subjective measurements to solve problems of analysis and decision-making, requiring the use of logical and mathematical models; in that way estimates should be expressed at least in the interval scale. The article substantiates the best solution of this problem by use of the rating scale which has properties of both ordinal and interval scales.Within the framework of the expert methods of quality measurements development two fundamental elements of the methodology of subjective measurements of subjective values from the standpoint of representative theory are formulated: 1) the rating scale as a modified scale of ranks, 2) the method of organization of the measurement process as a method of alternative assessment of expert preferences.Much attention is given to axiomatic of the rating scale having properties of both ordinal and interval scales. The algorithm of implementation of alternative assessment's of expert preferences method which is based on a special two-stage plan of alternative expert survey and statistical criterion of preferences' stability was suggested. In conjunction, the methodologies of subjective measurements of subjective values ensure the correctness of the rating scale's formation and conversion of the values of quality characteristics in the form of ratings in the corresponding values expressed at least in the scale of intervals.