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A. A. Platonov, A. J. Fiok
NEW PROBLEMS OF INSTRUMENTATION DESIGN AND MEASUREMENT THEORY

The paper deals with a new approach to the measurement systems design. It contains the review of selected new problems of contemporary metrology related with the design. Main attention of the paper has been concentrated around possibilities of formalisation, development of mathematical apparatus and optimisation of a design of optimal analogue-digital, intelligent measuring systems (MS). The task of the discussed approach is analytical support for system-level decisions at the most responsible initial stages of MS design. Its takes into account all available prior information about objects, processes and environment, as well as about the way of observation including characteristics of sensors, noises, errors and disturbances accompanying the measurement process.

J. Pekala, B. Kasprzak, J. Mroczka
PERFORMANCE ANALYSIS OF DISTRIBUTED MEASUREMENT SYSTEMS

Over the last years, standard network protocols and technologies have become very popular basis for distributed measurement system design. This paper describes a set of distributed measurement experiments designed with the use of selected network technologies. The performed test results give us an opportunity to compare these technologies and consider how particular technology affects the distributed experiment performance. We also discuss some important factors that influence performance. Finally, we give some advice for developers that we hope will help them to choose the best design methodology.

J. Nalepa
MODELLING AND SIMULATION OF MEASURING SYSTEMS USING THE SIMULINK SPECIALISED TOOLBOX

The paper shows the contents, application and way of using the specialised Toolbox for the SIMULINK language, which is designed for modelling and simulating measuring systems. This toolbox contains 22 models of measuring system elements and the block descriptions are accessible in Polish and English.

S. V. Muravyov
MODEL OF PROCEDURE FOR MEASUREMENT RESULT ERROR CORRECTION

An extension of the formal PSIQ-model of measurement procedure is proposed in order to have possibility to describe algorithms of measurement result correction in the ratio scale. An example of application of the model proposed to synthesis of a speedy correction method is given.

P. Mróz
TESTING DYNAMIC CHARACTERISTICS OF MEASURING DEVICES

The duration of the measurement is most important in metrology apart from measurement accuracy. Testing systems are used to speed up the object’s verification. It is needed to know the dynamic characteristics of the object to propose optimal operation algorithm of testing systems.
In the paper, the response measurement results of the thermoregulator to the step input function, using the method of the direct measure and the trapezoids method. are described and compared.

J. Milek, F. Kraus
USE OF ANALYTIC REDUNDANCY IN FAULT-TOLERANT SENSOR SYSTEMS

The paper presents a systematic design of fault-tolerant measurement systems for linear time-invariant processes. The discussed methods utilize analytic redundancy of the underlying process. Two multivariable linear model types (PCA for static and ARX for dynamic modeling) are considered. Both model types can be directly identified from the measured process data. Analysis of the primary and structured residuals enables very sensitive detection, isolation, and identification of single and multiple sensor and actuator faults. The fault diagnosis is conducted via analysis of the identified faults and can be followed by appropriate fault accommodation actions. A faulty sensor variable can be reconstructed using faultfree process variables and appropriate models. Faults which degrade sensor performance in a recoverable way (c.f. bias and gain errors) can be compensated using model-based sensor recalibration. Best data source in groups of doubled sensors can be selected through application of the voting scheme (where the third sensor is the soft sensor), thus enabling optimal sensor reconfiguration.

P. McGlone, J. McGhee, I. A. Henderson
IMPROVED RECURSIVE ALGORITHM FOR PERIODIC SIGNALS

An established robust recursive algorithm for the identification of periodic signals is further developed. Contemporary algorithms for recursive harmonic estimates are restricted in that, once a harmonic value is estimated after one cycle, no further improvement is attained. It is demonstrated that higher order algorithms offer data for the assiduous improvement to the calculated harmonic evaluation. Second and third order improvements to the algorithm are presented. Data smoothing of the recursive frequency analysis estimates allows marked convergence to the authentic value. The enhanced procedure illustrates its capacity to resolve the parameters of an unknown signal. The paper demonstrates that the algorithm is robust in that better convergence is still achieved in the presence of a noisecontaminated signal.

J. McGhee, I.A. Henderson, P. McGlone
ADAPTING CLASSICAL TAXONOMY FOR MEASURING SYSTEMS

Classical Taxonomy is the reservoir of methods and techniques used in the life sciences to bring scientific order to the grouping of living things. Although the orders or problems of Taxonomy were not clearly described until the late 19th century the methods used can be traced back to the time of Plato and Aristotle. This paper commences by introducing the main ideas associated with classical taxonomy. A brief overview of the classification of the sciences is given. Subsequently, classification principles are used to show that Instrumentation and Measurement Technology is a sub-science of what may be called Machine Science. Taxonomy is then adapted and developed for general application in machine systems but more specifically in measuring systems. It is clearly shown that machines, and hence measuring systems should be grouped on the basis of ”what they do”, or function, ”why they do”, or purpose, ”when they do”, or signal form, ”way they do”, or energy domain, ”where they do”, or location, ”how they do”, or structure and ”while they do”, or sensors.

G. Mauris, V. Lasserre, L. Foulloy
DISTRIBUTION-FREE POSSIBILITY MODELLING OF POOR SENSOR INFORMATION

At the application level, it is important to be able to define around the measurement result an interval which will contain an important part of the distribution of the measured values, that is, a confidence interval. When the sensor uncertainty is represented by a probability distribution, the confidence intervals can be easily deduced from it. But when the probability distribution cannot be identified due to poor sensor information, a more generalised representation must be used. To obtain confidence intervals in such a situation, available probabilistic methods are essentially the Bienayme-Chebychev and the Camp-Meidel inequalities. In this paper, after having recalled these methods, alternative approaches based on the possibility theory are considered. Distribution-free possibility distribution building based on the sets of all confidence intervals is proposed. According to the knowledge of uncertainty that is available, i.e. the range or the standard deviation of the measures, triangular and truncated triangular possibility distributions are respectively considered. These different possibility distributions which are fuzzy sets with uncertainty semantics are then compared in terms of the information provided.

R. Masnicki, J. Mindykowski
MEASUREMENT INSTRUMENT FEATURES ESTIMATION

In this paper the concept of virtual system, using graphical environment, designed for approving parameters of microprocessor measurement instruments was presented. The exemplary structure of virtual examining station used for research of metrological features of multifunction instrument for measurement of ship power engineering system parameters was discussed. The selected research results were shown. The automated algorithm of instrument metrological accuracy assessment was presented. The example illustrating the way of formulating of newly-designed measurement instruments research program was proposed.

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