Stefano De Falco, Nello Polese
The traditional control charts are based on the assumption that the measurement data relating to the average of each subgroup of the parameters under observation of a specific quality characteristic of product, process, system or service, are reported regardless of time stability of its own parameters. This condition is generally not verified in real cases, where we should take into account the lifecycle of measuring. In the case of monitoring of quality characteristic of a product for example, a parameter that is not in fact enjoy the property of time stability is its reliability, which is...
XIX IMEKO World Congress
· TC10
· 2009
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Leo Gusel, Rebeka Rudolf
Extrusion is one of the widest used and the most basic processes of plastic forming, and the metal flow in extrusion is affected by many factors, such as friction, die shape, billet temperature and so on. Among these factors, friction is the key boundary condition to determine the property of the extruded products. In this paper research and measurements of velocity fields and impact of friction on velocity distribution in forward extruded specimens of copper alloy were analysed using the visioplasticity method. The visioplasticity method was used to find the complete velocity distributions...
XIX IMEKO World Congress
· TC21
· 2009
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Fabio Leccese, Michael Magnone
A very simple circuit for a 3-bits discrete pure linear analog preprocessing folding ADC is presented. The device is based on the folding idea: the DAC, the summing node and the amplifier, fundamental elements of the classical architecture, are eliminated and replaced with an analogical signal preprocessing parallel structure named "channels". All channels are connected as a cascade and only three transistors constitute each one. The circuit has been widely analyzed by simulation and its simplicity guarantees easiness of realization, reduction of power consumption and reduction of total...
XIX IMEKO World Congress
· TC4
· 2009
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Eri Matsuyama, Du-Yih Tsai, Yongbum Lee, Katsuyuki Kojima
Information on physical image quality of medical images is important for imaging system assessment in order to promote and stimulate the development of state-of-the-art imaging systems. In this paper, we present a method for measuring physical performance of medical imaging systems. In this method, mutual information (MI) which is a concept from information theory was used to measure combined properties of image noise and resolution of an imaging system. In our study, the MI was used as a measure to express the amount of information that an output image contains about an input object. The...
XIX IMEKO World Congress
· TC13
· 2009
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Jose Sánchez, Ruiz Gerardo, Sergio Padilla, Benjamin Valera
Optical flats are required for spreading accuracy to mechanical and optical instruments, ordinarily by optical interference. Traceability of optical flats is ordinarily made by Fizeau interferometer. Traceability of this one requires higher accuracy flats, not available in secondary laboratories. These laboratories can accede to absolute self-calibration principles, by a method proposed by Bernard, who compares three flats among them through Zernike polynomials, representing these last their topographies. Two problems are found when the process is intended to set up: (a) the Zernike...
XIX IMEKO World Congress
· TC8
· 2009
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John Song, Samuel Low, Alan Zheng
In the uncertainty budget of Rockwell C hardness (HRC) tests, geometric error of the Rockwell diamond indenter is a major contributor. The geometric calibration of Rockwell diamond indenters has been a key issue for Rockwell hardness standardization. The National Institute of Standards and Technology (NIST) developed a microform calibration system based on a stylus instrument for the geometric calibration of Rockwell diamond indenters. Using that system, a NIST master standard Rockwell diamond indenter No. 3581 was established in 1995, by which approximately 300 standard reference material...
XIX IMEKO World Congress
· TC5
· 2009
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Talari Rambabu, Mita Dutta
In this paper the design, fabrication and electromechanical characteristics of a electrostatic torsional micromirror is presented. In addition to that the static characteristics of a micro-mirror based on the parallel-plate capacitor model are described.
XIX IMEKO World Congress
· TC3
· 2009
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Ludwik Finkelstein
The paper outlines the content and organisation of the generic concepts and principles of measurement and instrumentation. It argues that recent changes of technology and the political, economic and social environments demand a review of those principles and considers the resultant challenges and lines of advance. It distinguishes between measurement and instrument science. It considers the challenges presented by applications of measurement outside the physical sciences. It highlights the effect of advances in computing and the resultant convergence the principles of measurement and...
XIX IMEKO World Congress
· TC7
· 2009
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Zaccaria Silvestri, Patrick Pinot
A new device has been developed for the study of physisorbed elements on polished and large surface used in mass metrology. This technique, based on the analysis by mass spectrometry of desorbed molecules caused by heating under vacuum from the analyzed surface, is presented. The first application of this device is the study of the current and future mass standards to understand the reactivity of their surface depending of the storage conditions, of the cleaning process and polishing method. So, an example of surface contamination analysis by thermal desorption mass spectrometry (about...
XIX IMEKO World Congress
· TC3
· 2009
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Boris Katz, Peter Kornhauser, Shlomi Bitas
Modern building technologies (for example prestressed concrete to produce beams, floors, bridges, or installation, testing and monitoring of ground anchors) require the use of accurate force machines (hydraulic jacks). One component of successful building works is a correct and accurate calibration procedure of hydraulic jack for tensioning cables or anchors. This article analyzes two different calibration methods: By means of hollow load cell and thread bar and calibration in the closed frame. We analyze these methods using different accessories and their influence on the uncertainty of...
XIX IMEKO World Congress
· TC3
· 2009
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