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A. R. Valdés, A. Piratelli-Filho, D. P. Vieira Sato
UNCERTAINTY OF COMPONENTS OF VOLUMETRIC ERRORS

The aim of the present work is to calculate the uncertainty associated with volumetric error components in a Moving Bridge type Coordinate Measuring Machine (CMM). Two methodologies are presented for this purpose. The first consisted in equationing the components of the volumetric error using homogeneous transformations techniques; measurement of the geometric errors and Abbé offsets; mathematical models regarding each geometric error and Abbé offset were written and the law of uncertainty propagation was applied. The second methodology present simplified models to estimate the measurement uncertainty associated with volumetric error component, identifying the variables that influence the determination of geometry deviations, development of a mathematical model for the volumetric error components, development of a routine to evaluate uncertainty. It was concluded that the simplified models are adequate and easy to be applied. As conclusions, the components of volumetric error of X, Y and Z axes present uncertainty values close to 2.7, 4.0 and 2.0 mm, respectively.

K. Shirono, H. Tanaka, M. Shiro, K. Ehara
OPTIMIZATION OF CALIBRAION INTERVAL AND ADJUSTMENT LIMIT OF MESUREMENT DEVICE WITH STOCHASTICALLY DIFFUSIVE PROPERTY

A calibration and an adjustment of measurement device are keys to realize a metrological traceability. (Calibration means just checking without adjustment in this paper.) Although the traditional online quality engineering can be one of applications to determine calibration interval and adjustment limit in terms of cost, approximations used in the traditional quality engineering are too rough to take stochastic behaviour of a bias in a device into consideration. In this paper, we propose an optimum calibration interval and an optimum adjustment limit for a measurement device with a bias in accordance with Brownian dynamics concerning a long-term cost.

Giampaolo E. D’Errico, Nadir Murru
REAL–TIME ESTIMATION OF DYNAMIC MULTI–DIMENSIONAL MEASURANDS

This paper is devoted to the study and implementation of real–time techniques for the estimation of time–varying, contingently correlated quantities, and relevant uncertainty. An estimation algorithm based on a metrological customization of the Kalman filtering technique is presented, starting from a Bayesian approach. Moreover, a fuzzy–logic routine for real–time treatment of possible outliers, is incorporated in the overall software procedure. The system applicability is demonstrated by results of simulations performed on dimensional measurement models.

Huang Songtao, Mao Shuonan, Ma Yuming, Chen Daosheng
RESEARCH ON PROTECTION DESIGN FOR PREVENTING FROM FRAUD USING TRUCK SCALES

The cases of fraud using truck scales in trading settlement are increasing frequently in some countries. This paper comprehensively analyses the possibility of fraud using truck scales, base on the entire measurement data chain of the weighing system. In this paper, the author gives one acceptable protection solution from the point of system design, instruments design and sensor technology, which connects the new technology of MEMS.

F. Pavese
ROUNDING AND NOTATION, NAMELY WHEN USING STIPULATIONS IN THE DEFINITION OF MEASUREMENT UNITS

This paper intends to tackle, in the context of measurement and the definition of measurement units, a problem well known in computing science, the inherent propagation and accumulation of rounding errors throughout the intermediate steps of numerical calculation, and some issues in notation, namely of integer numbers.

F. Pavese
CORRECTIONS AND INPUT QUANTITIES IN GUM-COMPLIANT MODELS

The Guide to the expression of uncertainty in measurement (GUM) requires, "that the results of a measurement have been corrected for all recognised significant systematic effects and that every effort has been made to identify such effects" (3.2.4), before the issue of evaluating their uncertainty is tackled. In addition, the GUM also requires that a model is used, expressing the functional dependence of the measurand on the identified input quantities. The paper discusses the inter-relations between the so-defined two sets of influence quantities and proposes to unify their treatment.

A. Albert Garcia-Benadí, B. Erik Molino-Minero-Re, C. Joaquín del Río-Fernández, D. Antoni Mànuel-Lázaro
EVALUATION OF THE R&R AND THE COMPATIBILITY INDEX FOR NONINDEPENDENT MEASUREMENTS

This paper describes the methodology of the compatibility criteria "En" and the methodology of R&R. With this paper we’ll use the methodology R&R for the evaluation of the compatibility criteria between the staff of the laboratories, where independent measurements aren’t insured.

N. Greif, H. Schrepf
HOW TO PROVE AND ASSESS CONFORMITY OF GUM-SUPPORTING SOFTWARE PRODUCTS

This paper describes how to prove and assess GUM conformity of software products which claim to offer a GUM-conform calculation of measurement uncertainties. To bridge the gap between the GUM guideline and the required test specification, an analysis of the GUM from the perspective of software testing is presented. Roughly, the benefit and the limits of the developed validation procedure are outlined.

F. Ezedine, J.M. Linares, J.M. Sprauel, W.M. Wan Muhamad
HYBRID METHOD FOR DETECTING INFLUENTIAL FACTORS FOR TRACKING CAMERAS IN A CAVE

The industrial world increasingly uses Virtual Reality technology in design and research processes, in order to improve quality, but also to stick to the concept of a green technology. The accuracy and precision of VR systems such as the Cave Automatic Virtual Environment (CAVE), directly influences the range of possibilities of these processes. So, the aim of this paper is to describe a hybrid method (Monte Carlo Method and Design Of Experiment using Hadamard matrix) used to adjust tracking system cameras in a CAVE. A model of the tracking system is created based on factors of the camera, adjustable or not. This method provides a classification in order of influence of these adjustable factors over the CAVE tracking accuracy. This hybrid method also improves the accuracy of the VR system from Aix Marseille Université and to run the application of a knee surgery with high quality of immersion.

W. Heins, G. Gewiss, C. Bohn, H.-P. Beck
STATE-SPACE FORMULATION FOR THE NODAL LOAD OBSERVER FOR SMART ELECTRICAL GRIDS WITH IMPERFECT MEASUREMENT INFRASTRUCTURE

This paper presents a discrete-time state-space formulation of the nodal load observer for middle-voltage distribution grids, developed at Clausthal University of Technology. The nodal load observer is a procedure for the on-line reconstruction of unknown load and generation in a middle-voltage distribution grid based on measurements of complex nodal voltage or line current. Conceptually it is inspired by the idea of applying the state observer concept, as known from control system theory for general dynamic systems, to a set of algebraic equations. A first draft of the method was developed. In the present paper, an alternative formulation is presented, which leads to a discrete-time version of the method and reveals that in fact the nodal load observer can be interpreted as a disturbance observer structure and is closely related to dynamic state estimation, which allows for system-theorybased general analysis and extensions.

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