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Abstract

Dynamic measurement challenges are ubiquitous in metrology and can be found in many measurement applications that are not conventionally regarded as dynamic. We present four recent examples of work at the UK's National Physical Laboratory that demonstrate how modelling and simulation can contribute to improved understanding of dynamic measurement tasks. The examples are (i) a software simulation of a lock-in amplifier, (ii) a simulation of a sensor network in which one of the sensors has insufficient bandwidth for the measurement task and Kalman filter based data fusion is used to aggregate the sensor outputs, (iii) a study of performance imperfections in a clock embedded in a wireless sensor node using a Monte Carlo based method for simulating counting errors, and (iv) a simulation of wave propagation in a shock tube in which the lattice Boltzmann method was used to study non-ideal behaviour of the shock tube. It is shown that simulation (both physically based and phenomenological) is useful in designing measuring systems and identifying and quantifying measurement uncertainties and that the development of simulation software requires the developer to have a clear understanding of the measuring system of interest.

Abstract

The second part of the article describes the technology of marine engine diagnostics making use of dynamic measurements of the exhaust gas temperature. Little-known achievements of Prof. S. Rutkowski of the Naval College in Gdynia (now: Polish Naval Academy) in this area are presented. A novel approach is proposed which consists in the use of the measured exhaust gas temperature dynamics for qualitative and quantitative assessment of the enthalpy flux of successive pressure pulses of the exhaust gas supplying the marine engine turbocompressor. General design assumptions are presented for the measuring and diagnostic system which makes use of a sheathed thermocouple installed in the engine exhaust gas manifold. The corrected thermal inertia of the thermocouple enables to reproduce a real time-history of exhaust gas temperature changes.

Abstract

Much research has gone into establishing the temperature gradients that exist inside a burning cigarette. These temperature gradients should correspond to changes in the density of the tobacco column due to the condensation and subsequent re-evaporation of volatiles resulting from pyrolysis, combustion, and final ash formation. These dynamic measurements on the burning cigarette were made using a modified beta thickness gauge. A beam of collimated beta particles from a 32P-source is projected through the side of a cigarette at a fixed position. The cigarette is allowed to burn past the focused beta beam. The number of transmitted particles is dependent upon the density of the mass penetrated by the incident particles, and is reflected as a change in the number of counts detected per unit time. A density profile of the burning cigarette has been established for both the puffing and static modes. These density changes are correlated with published temperature profiles. The buildup of the volatile materials (mostly water) on the tobacco rod behind the pyrolytic region is presented. The rate of evaporative losses of these condensables is shown to be dependent on puff count (cigarette length). A detailed density profile of the condensing materials from a single puff has been established. The relationships of these density changes to current smoke formation theories are discussed

) 47-51. [16] B.G. Xu, C.M. Murrells, X.M. Tao, Automatic measurement and recognition of yarn snarls by digital image and signal processing methods, Text. Res. J. 78 (2008) 439-456. [17] Z.J. Li, R.R. Pan, W.D. Gao, Formation of digital yarn black board using sequence images Text. Res. J. 2016 (86) 593-603. [18] Y. Guo, Tao X M, Xu B G, Choi K F, Hua T and Wang S Y 2010 A continuous measurement system for yarn structures by an optical method Meas. Sci. Technol. 21 115706-115720 [19] J. Feng, B.G. Xu, X.M. Tao, J. Feng, B.G. Xu, Dynamic measurement and modelling of

Current Directions in Biomedical Engineering 2019;5(1):343-346 Constanze Neupetsch*, Eric Hensel, Michael Werner, Sven Meißner, Jan Troge, Welf-Guntram Drossel, and Christian Rotsch Development and Validation of Bone Models using Structural Dynamic Measurement Methods https://doi.org/10.1515/cdbme-2019-0086 Abstract: Vibration measurement and signal analysis methods are common to evaluate the functionality and characteristics of technical components in different industrial and scientific areas. Modal analysis for example is a standard method to char- acterize the

S. Miyashiro ** und H. Gronig Institut für Luft- und Raumfahrt der RWTH Aachen (Z. Naturforsch. 32 a, 1387-1392 [1977] ; eingegangen am 21. September 1977) Dynamical Measurements on an N»-Laser Using optical fibers and photodiodes, the local, spontaneous emissions along an N2-laser channel have been for the first time measured with a sampling technique. From the relations among the laser power, the gas pressure, the voltage on the storage capacitor and the discharge time dif­ ference along the laser channel, the dynamical behaviour of an N2-laser was studied

sampling frequency using an A/D Dynamic measurements of nip force variations during post-printing of corrugated board Erik Hallberg Hofstrand, Magnus Lestelius and Peter Rättö, Karlstad University, Sweden 4805 06-03-14 14.00 Sida 111 112 Nordic Pulp and Paper Research Journal Vol 21 no. 1/2006 converter (Daqbook 260, IOtech Inc., Cleveland U.S.). The recorded data are converted into force data using a calibration curve. Fig 2 shows an example of a recorded force signal when the nip force is set to 100 N and neither the printing form cylinder nor the impression

was revealed Photometric method for dynamic measurements of paper roughening after a moistening printing nip Peter Åslund, Per-Åke Johansson and Erik Blohm, STFI-Packforsk AB, Sweden 1404 04-11-23 14.06 Sida 460 461Nordic Pulp and Paper Research Journal Vol 19 no. 4/2004 while a CCD-camera continuously captured images of the paper surface. To analyse the surface roughness, an image analysis method was developed based on the intensity differences in the images of the illuminated surface. A pioneer in this field was Horn (1977) who introduced a method of

Technisches Messen 48. Jahrgang 1981 Heft 6 t m 225 V 3633-2 Die dynamische Erfassung des relativen Versatzes zweier periodischer nahezu synchroner Vorgänge The dynamic measurement of the relative displacement of two periodic, nearly synchronous phenomena Schlagwörter: Polradwinkelmessung, Synchronmaschine, Von Μ. PANDIT Pseudozufallsfolge In bestimmten Energieumformungs- bzw. Übertragungs- systemen ist es erforderlich, die momentane relative Lage zweier periodischer nahezu synchroner Vorgänge zu messen. Ein typisches Beispiel eines solchen Falles ist

ANWENDUNGEN at 2/2005 Stationäre und dynamische Motorvermessung zur Auslegung von Steuerkennfeldern – Eine kurze Übersicht Static and Dynamic Measurements of Combustion Engines for Optimization of Control Mappings – A Brief Survey Ralf Zimmerschied, Matthias Weber und Rolf Isermann In Form einer Übersicht werden unterschiedliche Vermessungsstrategien (Identifikati- onsmethoden) von Verbrennungsmotoren vorgestellt, die gegenüber den klassischen Rastermethoden eine wesentliche Verkürzung der Messzeit erzielen. Das Ziel der Vermessung ist die Modellbildung für die