IMEKO Event Proceedings Search

Page 743 of 936 Results 7421 - 7430 of 9356

E. Lunca, A. Salceanu, S. Hanganu, C. Donciu
VIRTUAL INSTRUMENT AIMING TO EXTEND THE CAPABILITIES OF THE SPECTRUM ANALYZERS

The paper presents a virtual instrument for measuring the insertion loss, signal-to-noise ratio, carrier-to-noise ratio and frequency response. Since most of the spectrum analyzers are equipped with a GPIB or RS-232 interface, here demonstrate that LabVIEW graphical environment represents the proper tool to develop such applications. Sometimes, instrument producers provide specific software, but using LabVIEW some additional costs can be eliminated by user developed software.

Mariana Milici
THE ADVANTAGES OF IMPLEMENTATION AT MULTIMEDIA TECHNIQUES IN INSTRUMENTATION AREA

The new implementation tendencies of multimedia techniques in all areas that involve the communication and data transfer as and the interface man-engine found applications in instrumentations area also. The orientation of techniques, methods and measurement devices toward digital equipments does the multimedia methods utilisation to be easy and allows a facile and efficacious using of equipments along with the appearance of virtual instruments with specialised functions.

Dan Milici
COMPUTERIZED SYSTEM FOR TESTING AND FORMATION THE SPEED OF BACKWARD PUSH OF SPORTSMEN

An important parameter in sportive training it’s represented by the speed of reaction of sportsmen on the competitions. This paper presents a digital system meant for sportive probation in order to obtain some superior performance.

E. Lunca, M. Cretu, V. David, C. Donciu
A VIRTUAL INSTRUMENT FOR REMOTE MONITORING OF ELECTROMAGNETIC FIELD

The paper presents a virtual instrument completely based on LabVIEW for remote monitoring of electromagnetic field across the local area network or Internet environment. As our primary intention was to implement a virtual instrument able to measure and display directly the E-field strength values, the access to the instrument is simply performed via the LabVIEW built-in web server.

S.M. Yermishin, A.V. Lopatin
CONDUCTING CALIBRATION MEASUREMENTS BASED ON THE VIRTUAL STANDARDS® TECHNOLOGY

The authors propose to use the Virtual Standard® technology in conducting calibration operations for a wide range of measurements. The Virtual Standard® technology is a universal technology for determining and introducing corrections in measuring device readings to reduce their errors. Theoretical principles underlying the Virtual Standard® technology are discussed, and their operation flow chart and some experimental findings are provided.

Valery A. Granovsky
VIRTUAL MEASUREMENT INSTRUMENTS: TRACEABILITY FUNDAMENTALS AND METHODS

The problems of metrological ensuring virtual measuring instruments (VMI) are discussed. The VMI classification is proposed. The principles of measuring instrument legalization are formulated as a base for the problem solving. As the basic problems, structural identification of VMI, and unauthorised access, and VMI calibration and standardization are pinpointed. It is shown that complete calibration is foreground for VMI similar as to usual measuring instruments, without necessity to certify, separately, measurement software.

Vaclav Papez, Stanislava Papezova
NOISE FIGURE MEASUREMENT IN HIGHLY MISMATCHED SYSTEMS

This paper describes problems of measuring the noise figure when the noise figures are low and there is high mismatching of measurement system. Measurement errors can be identified using this method. Methods limiting the influence of a measurement system with real parameters are presented. The available accuracy in dependence on the parameters of the measurement system is described.

Karol Korcz, Beata Palczynska, Ludwik Spiralski
UNCERTAINTY IN MEASURING THE NOISE FACTOR OF CASCADE-CONNECTED LINEAR TWO-PORTS

The paper presents the derived dependence on the total noise factor of cascade-connected linear two-ports in the conditions of energy mismatching. The method of assessing the uncertainty in measuring this factor, which takes into account propagation of standard partial uncertainties of the measurement of the set of four noise parameters, disposable power gains and input and output impedance of particular two-ports, is determined. The uncertainty analysis takes into account the correlation among these parameters. A strict dependence between the mismatching stages of two-ports in the cascade and the uncertainty in measuring the total noise factor is shown. Sensitivity coefficients determining the participation of particular standard partial uncertainties are defined. The results of the analyses and simulations of particular uncertainties components, which were carried out for a typical communications receiver, are presented.

Romuald Masnicki, Janusz Mindykowski
UNCERTAINTY AS THE COMPONENT OF THE MEASUREMENT RESULT IN MICROPROCESSOR INSTRUMENTS

A traditional description of the measurement result obtained with the use of a definite measurement instrument is complemented by the information about its accuracy on the basis of technical specifications given by its producer or verified in checking and legalisation procedures. The paper presents the premises resulting from currently available technical possibilities, which show that it is purposeful to complement the set of functions realised in a microprocessor instrument with additional properties enabling the instrument user to access the information about the uncertainty of the measurement result. The configuration of the measurement instrument, which enables an access, apart from the measurement result, to the information about the uncertainty as the component of the result, is presented. The conditions referring to the set and programme configuration of the instrument, indispensable for the realisation of the proposed idea, are pointed out. The main ideas of the presented paper will be also found in the authors’ work.

Stefica Celap
THE ESTIMATION OF UNCERTAINTY BY THE UTILIZATION OF VALIDATION AND QUALITY CONTROL DATA, LEAD IN GASOLINE BY AAS

This protocol was developed to estimate the uncertainty of measurement of a chemical analysis by utilizing in-house validation studies and quality control data. The approach was to generate an estimate of the uncertainty across the analytical concentracion range. This was to be expressed as a mathematical equation or factor that could be inserted into a Laboratory Information Management System (LIMS) and thus produce an uncertainty estimate from an entered analytical result.
The aim is to identify as many sources of uncertainty as possible and account for them by appropriatte precision and trueness studies. Any additional sources of uncertainty are evaluated by other means such as calibration certificates, published dana, etc.. It is not necessary to evaluate every source of uncertainty if they are deemed insignificant, unless there are a large number of them. Uncertainty components that are less than one third of the largest component are not evaluated in detail. A preliminary estimate of the contribution of each component or combination of components to the uncertainty is made and those that are not significant eliminated . The uncertainty contributions is expressed as standard deviation, and combined according to the appropriate rules, to give a combined standard uncertainty. Coverage factor (2 for normal distribution) is applied to give an expanded uncertainty.

Page 743 of 936 Results 7421 - 7430 of 9356