9762 papers found
The paper discusses the metrological conditions required for evaluations performed in weak scales to be considered measurements. The problem of uncertainty expression is taken into account, and the need of models applicable to ordinal and nominal scale measurement is highlighted.
The article deals the vibration of contacts of electro-mechanical relays (and mechanical contacts generally), its properties, its measurement and a special measuring instrument built for this purpose. The vibration of contacts is caused by ringing of the springs (and other mechanical components) carrying the contacts. It generates quasiperiodic interruptions of current flowing through a moving contact-pair. These interruptions cause problems e.g. when this current controls fast semiconductor circuits or when the contact-pair is loaded by a remarkable current and sparks and burning of...
When constructing the sensing system using multi-sensor, two major tasks must be achieved: one is to build up the entire structure of the sensing system and the other is to show the algorithm for processing a huge amount of information obtained by the system. In this paper we propose the active multi-sensor system with knowledge-base and also the system based on belief concept closely related with knowledge-base, with making sensors cooperative.
The paper solves a physical quantity measurement enhancement problem under a shifted power sensor-transfer function with known and unknown values of its power exponent n. The problem is solved on the basis of a functionalalgorithmic method, used to linearize a general transfer function, existing for a digital meter, as well as of a redundant measurements method, used for automatic correction of systematic errors. It is shown, that the distinctive feature of the former method is application of respective quantities substitution formulas. The essence of the proposed methods is described. The...
Principles of building R, C, L-meters with wide functional capabilities and using Whetstone as base are described. Such meters can find a wide application in measuring instruments and in complex information control system
This paper presents the use of numerical finite element (FE) technique for modelling and design of capacitive sensors. The general mathematical approach to FE modelling and design of capacitive sensors is established. Two case studies are considered to show the versatility and efficiency of the developed modelling methodologies. The first involves a multielectrode capacitive sensor for two-phase flow imaging and the second – a robust capacitive angular position sensor. It is shown that although these sensors are used in very different applications, the same modelling strategies are...
The stationary air - cored induction coils are often used for the measurement of AC magnetic fields in the air. The voltage induced in classical voltage output coil is proportional to the time rate of change of the magnetic flux and to the turn – cross-section product N A . Increasing of the number of turns N causes increasing of the parasitic capacitance. Parasitic capacitance with the inductance of the coil creates resonant circuit and thereby decrease the maximum measured frequency. In the case of the short-circuited coil the frequency range of the sensor is essentially expanded....
A proposal for a lossless adaptive compression algorithm to be used in continuous measurement data recording is presented in this paper. The operation implemented by the algorithm can be termed the signal compression before quantization. Although the algorithm itself is inertialess, its efficiency depends on the dynamics of the measurement signal compression. Thanks to the adaptation of the compression algorithm parameters to the variability characteristics (i.e. to the dynamics) of the signals recorded, the compression level can be optimised. The algorithm, method for the adaptation of the...
The paper considers the significance of Design Theory in Measurement Science. It presents a modern view of design as a knowledge acquisition and transformation process. A brief outline of the classical model of design is provided. A model of the design process as a knowledge transformation process, based on a board architecture is proposed. A view of design concepts as models, and of design concept generation and transformation as a problem solving process, is presented. Reference is made to practical examples.
The Hungarian products must satisfy the increasing quality demands being in Hungary and in abroad. Developing the quality of the machine production is essential requirement of competitiveness of the Hungarian industry. The Department of Production Engineering applies a wide range of the Computer Aided Industrial Metrology and Quality Assurance Softwares in education and in research. The paper introduces some methods for solving of the quality assurance tasks.